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Black-and-white-casqued hornbills are found in forests and savannas throughout West and Central Africa. The subspecies Bycanistes s. subcylindricus ranges from Sierra Leone and northeast Liberia across the Ivory Coast to western Nigeria, and the subspecies, B. s. subquadratus, ranges from eastern Nigeria, Cameroon, and the Central African Republic to Sudan, Zaire, Uganda, southwest Kenya, and northwest Tanzania (del Hoyo et al., 2001). An isolated population of B. s. subquadratus also exists in Angola (Lewis and Pomeroy 1989). (del Hoyo, et al., 2001; Lewis and Pomeroy, 1989)
Black-and-white-casqued hornbills are most commonly found in subtropical/tropical lowland and montane forests, where they reach altitudes of 2,600 m (del Hoyo et al., 2001; BirdLife International 2008). This species is less frequently seen in artificial landscapes such as plantations or urban areas, heavily degraded forests and dry savannas (BirdLife International 2008). ("BirdLife International Species factsheet: Bycanistes subcylindricus.", 2008; del Hoyo, et al., 2001)
Black-and-white-casqued hornbills are fairly large, mainly black hornbills with white lower backs and rumps, upper and under tail-coverts, thighs, bellies, and vents. The central pair of rectrices is all black, while the rest of the tail feathers are black-based and extensively white distally. The secondaries and inner primaries are mostly white with black bases. This species has grey-tipped facial feathering, which gave rise to another common name, gray-cheeked hornbills. (del Hoyo, et al., 2001; Kalina, 1988; Kemp, 1995)
Males have red eyes, blackish facial skin and a dark brown bill with a high-ridged, laterally flattened casque which has a broad cream-colored base. Casque pattern varies individually sufficiently to aid scientists in individual recognition (Kalina 1988). Females have a much smaller all-blackish bill, and the casque is reduced to a lower, rounded ridge on the basal upper mandible. Females have pink facial skin and brown eyes. Males are larger than females, weighing between 1,078 and 1,525 g, while females weigh between 1,000 and 1,250g. (del Hoyo, et al., 2001; Kemp, 1995)
Juveniles emerging from the nest have small bills lacking casques (Kilham 1956; del Hoyo et al., 2001). Birds less than a year of age have brown feathers on the forehead and around the base of the bill (Kalina 1988; Kemp 1995). Subadults have a high degree of vascularization in the area of the future casque. The facial feathers turn from brown to grey by 10 months of age (Kemp 1995). (del Hoyo, et al., 2001; Kalina, 1988; Kemp, 1995; Kilham, 1956)
The subspecies B. s. subquadratus is larger than B. s. subcylindricus and has more cream coloring along the casque and more white below (del Hoyo et al., 2001). (del Hoyo, et al., 2001)
Black-and-white-casqued hornbills are monogamous, breeding seasonally from January to May in Central Africa and August to March in eastern Africa. Their breeding season coincides with local rainy seasons, so they can take full advantage of the abundance of fruit and arthropods at this time (del Hoyo et al., 2001; Kalina 1988). (del Hoyo, et al., 2001; Kalina, 1988)
Both male and female black-and-white-casqued hornbills care for, protect, and provide for their offspring during the nesting and fledgling stages.
Black-and-white-casqued hornbills have been known to live up to 31.8 years in captivity. (Kemp, 1995)
Black-and-white-casqued hornbills are active during the day. They are nomadic during the dry, non-breeding season and actively defends their nesting area when breeding. (Kalina, 1988)
Movements and dispersion of these hornbills vary seasonally. In the few months prior to and during breeding, pairs actively defend their nesting tree. They make repetitive “long-calls” and “high-pitched screams” while perched atop the tree. All other approaching hornbills are chased away. During the dry season, when this species does not nest, they are nomadic, sometimes traveling over 6 km to visit fruiting trees. (Kalina, 1988)
Black-and-white-casqued hornbills are quite vocal, with a large repertoire of calls, one of which can be heard from a distance of 2km (Kalina 1988). Calls differ between the two subspecies. Bycanistes s. subcylindricus makes mournful hooting notes, whereas B. s. subquadratus makes quacking notes uttered at a higher pitch and frequency (Kalina 1988; Kemp 1995) (Kalina, 1988; Kemp, 1995)
Black-and-white-casqued hornbills are mainly frugivorous, with fruit comprising 90% of their diet, 56% belonging to Ficus species. They forage by hopping from branch to branch in the rainforest canopy and reaching for fruit with the tip of the bill, which they then swallow whole. This species is known to consume over 41 plant genera (Kalina 1988; del Hoyo et al., 2001). (del Hoyo, et al., 2001; Kalina, 1988)
Black-and-white-casqued hornbills also consume birds, eggs, insects, bats, snails, lizards, mollusks, other small animal prey, mosses, lichens, and fungi. The carnivorous component of the diet is increased while breeding. These hornbills, alone or in flocks, occasionally raid weaver colonies (Ploceidae) or Egyptian rousette bat (Rousettus aegyptiacus) roosts and have also been reported feeding on various species of galagos (Galago). They are frequently seen foraging alongside monkeys or squirrels. (del Hoyo, et al., 2001; Kalina, 1988; Kemp, 1995; Kilham, 1956)
Carnivores, apes, monkeys, snakes, raptors, and humans all prey on these hornbills. The placement of their nests high off the ground helps reduce much nest predation by carnivores, but raptors such as crowned eagles (Harpyhaliaetus coronatus) commonly prey on them (Kalina 1988). (Kalina, 1988)
Black-and-white-casqued hornbills mediate seed dispersal of rainforest trees, by defecating or regurgitating seeds (Kalina 1988). (Kalina, 1988)
Like all hornbills, black-and-white-casqued hornbills. with their unusual behaviors and impressive casques are interesting to many different groups of people, and therefore contribute to the success of ecotourism in Africa. They help to regenerate native forest through seed dispersal. (Kalina, 1988)
There are no adverse effects of black-and-white-casqued hornbills on humans.
Black-and-white-casqued hornbills are not globally threatened. They are still common in central and eastern Africa, though less so in western Africa. This species is currently locally abundant because it survives in degraded forest and open areas; however, forest degradation in Africa means that hornbills now occur in more open areas with few large trees, which makes them more prone to hunting.. (del Hoyo, et al., 2001)
Tanya Dewey (editor), Animal Diversity Web.
Abby Velting (author), Michigan State University, Pamela Rasmussen (editor, instructor), Michigan State University.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
uses sound to communicate
living in landscapes dominated by human agriculture.
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
Having one mate at a time.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
generally wanders from place to place, usually within a well-defined range.
an animal that mainly eats all kinds of things, including plants and animals
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.
associates with others of its species; forms social groups.
living in residential areas on the outskirts of large cities or towns.
uses touch to communicate
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
uses sight to communicate
breeding takes place throughout the year
2008. "BirdLife International Species factsheet: Bycanistes subcylindricus." (On-line). Accessed September 03, 2008 at http://www.birdlife.org/index.html..
Kalina, J. 1988. Ecology and Behaviour of the Black-and-White casqued Hornbill Bycanistes subcylindricus in Kibale Forest, Uganda.. PhD Michigan State University, Thesis, 1: 1-100.
Kalina, J. 1989. Nest intruders, nest defense and foraging behavior in the Black-and-white Casqued Hornbill Bycanistes subcylindricus.. Ibis, 131: 567-571.
Kemp, A. 1995. Bird Families of the World: The Hornbills Bucerotiformes.. New York: Oxford University Press.
Kilham, L. 1956. Breeding and other habits of casqued hornbills (Bycanistes subcylindricus). Smith Misc Coll., 131 (9): 1-45.
Lewis, A., D. Pomeroy. 1989. A Bird Atlas of Kenya. London: CRC Press.
del Hoyo, J., A. Elliot, J. Saragatal. 2001. Handbook of the Birds of the World. Barcelona: Lynx Edicions. |
Divide with Number Line Models uses number lines to demonstrate division of fractions.
You can input the divisor and dividend for a division of fractions example. The dividend or divisor each must be less than 7. The quotient must be less than 20.
If you want just a whole number for for the divisor or the dividend, type in 0 (zero) for a numerator. If you do not want a whole number, type in 0 (zero) for the whole number. Do not type in 0 for the denominator.
Think of the dividend as the length of cake and the divisor as the length of a container. If the cake is 5 1/2 units in length and each container pan can hold 3/4 of a unit, you can fill 7 containers with one piece left over. The piece will fill 1/3 of a container so you can fill 7 1/3 containers.
Visualizing division examples is not easy. You are told that division by a number can be done by multiplying by the reciprocal of that number:
Another method would be to write the dividend and divisor over a common denominator. With like fractions you can divide the dividend numerator with the divisor numerator. For example:
This method is not the easiest but it helps us to see the relative sizes of the dividend and divisor.
You can then compare this with the image for the same example. Notice the dividend has 21 common denominator marks and the divisor has 8 common denominator marks giving 21/8 for the quotient.
On the left is a <SHOW COLOR> check box. Uncheck <SHOW COLOR> to turn off the quotient. This will allow the teacher to ask the student to demonstrate the size of the quotient.
The <EXPLAIN> check box will show the dividend, divisor, and quotient. Uncheck <EXPLAIN> to turn the explanation off, allowing the teacher or student to demonstrate how the quotient is found.
Uncheck the <SHOW INPUT> button to make the dividend and divisor input boxes act the same as a password input box. This will allow you to ask your students the factors and and the product as pictured.
Start with a dividend of 2 1/4 and a divisor of 1/4. Notice how 9 divisor amounts fit into the dividend. Increase the dividend by 1/4 increments. For example, keep the dividend at 2 1/4 and change the divisor to 1/4, 1/2, 3/4, and continue with this pattern. See how quotient decreases as the divisor increases. You are finding how many divisor sections fit into the dividend.
Keep the divisor and the dividend the same. For example, divide 1 1/2 by 1 1/2. Notice how the divisor fits into the dividend once.
Notice that if the divisor is larger than the dividend, the quotient is less than one. Try 1 3/4 divided by 3 1/2. Notice that only half the divisor fits into the dividend.
Divide one(1) by 3/4. (Enter 1 for the whole number, 0 for the numerator and 1 for the denominator. Then enter 0 and 2/3 for the divisor. You will get 3/2 or 1 1/2 for the quotient. This shows that 1 divided by any fraction will give the reciprocal (inverse) of the fraction.
Demonstrate how as the divisor increases the quotient decreases. Try a Dividend of 3 1/2 and a divisor of 0 1/2. Increase the divisor to 1 1/2, then 2 1/2 and watch the quotient decrease, showing that the larger the divisor, the smaller the quotient.
How do you explain what's really going on when you divide 1/2 by 2/3? This is hard to picture, but if you write both 1/2 and 2/3 over a common denominator (making them like fractions) you will have 3/6 divided by 4/6. This is easier to see because you can consider the numerators 3 and 4. So dividing 1/2 by 2/3 is the same as dividing 3 by 4, giving you 3/4. Tick marks are shown to show the common denominator.
You may copy the screen by pressing <Print Screen> on the keyboard. This copies the screen into Windows Clipboard™. The screen can then be pasted into Windows Paint™ or your favorite imaging program. Windows Paint™ will allow you to crop, print, or save the image.Windows 7 users can use the Snipping Tool™ to capture any part of the screen. These images can be edited and saved in PNG, GIF(recommended) or JPEG formats. |
ONE MILLION YEARS B.C. - Humans begin artificial CO2 emissions
'Could be an essential part of what makes us human'
Opinion Fossil-furtling boffins have announced that the human race was burning things - and irresponsibly releasing carbon dioxide into the atmosphere - fully a million years ago, some 300,000 years earlier than had been thought.
"Human ancestors as early as Homo erectus may have begun using fire as part of their way of life," enthuses anthropologist Michael Chazan, co-leader of a team which discovered unfeasibly ancient traces of wood ash at the Wonderwerk Cave in South Africa.
The massive Wonderwerk is located near the edge of the Kalahari desert, and was already known to the boffinry community as having been extensively occupied by prehistoric humans and pre-humans. Fresh sampling and analysis of sediments from the cave revealed plant ashes and burned bone fragments, both of which - according to the scientists - appear to have been burned on site rather than washed or blown into the cave. The researchers also found surface discolorations which they say indicate burning.
"The control of fire would have been a major turning point in human evolution," says Chazan. "The impact of cooking food is well documented, but the impact of control over fire would have touched all elements of human society. Socializing around a camp fire might actually be an essential aspect of what makes us human."
Chazan and his colleagues' research is published in the Proceedings of the National Academy of Sciences. ®
For most of prehistory, our natural human penchant for burning things didn't have a major impact as there were not that many people about and the plants we burned would tend to be replaced by others, so drawing the emitted CO2 back out of the atmosphere. But then tools and farming came along, where we would cut down (and then burn or decompose) carbon-dense forests and replace them with comparatively minimalist crops or grazing (and then sometimes with accidental dust bowls, deserts etc).
Funnily enough it was at around this point that prehistory ended as very small numbers among the human race acquired enough spare time and resources to start writing things down. Occasionally there were hints that we might start burning things not just for heat or to get rid of them but to generate other forms of energy - but usually these very disturbing and dangerous ideas went away, and generally to get these other forms of energy we would use windmills or water wheels, or muscle power.
Then, disaster, as annoying British people worked out ways to turn burning fuel into useful energy wholesale. We had already started digging up fossilised plants to supplement our supplies of ordinary trees etc, and this trend accelerated hugely. In just a couple of hundred years, significant sections of the human race have acquired enough spare time and resources that just about everyone - not just the wealthy and specialist classes - can write things down and read them.
Many people feel that reading, writing, and other such non-food-gathering, energy-related activities are a big part of what make us human - like socialising round the old camp fire. However all this has led to a lot more CO2 being emitted, which some say means we should go back to windmills and waterwheels: though nobody is openly advocating a return to universal mass illiteracy. |
The Lost Doc
Anne Larkin Oaks
*Rationale: Decoding is step that makes learning to read quick and easy. In order to be able to decode, the connection of graphemes and phonemes must be known. Short vowels are some of the most important phonemes that must be learned. For this design lesson, o = /o/ will be the main focus. Students will practice o = /o/ in spoken and written forms and they will make the connection between the grapheme and the phoneme.
Primary paper, pencils, Doc in the Fog (Educational Insights), cards with o = /o/ written on them, picture page with these o = /o/ items: pot, frog, sock, stop, box, fox, clock.
*Procedures for carrying out the lesson in detail, with numbered steps.
1.Writing is a top secret code in which we have to be taught what different
letters represent. When we speak, our mouth moves differently when we say
different words. Today we are going to see how our mouth moves when we say words
that have the o = /o/ sound. Can anyone give me some words with the o = /o/
2. Ask Students: Have you ever had to open your mouth wide for the doctor and say /o/? Well, the /o/ mouth move is the one we are looking for in words. Let’s try it. Pretend you are at the doctor. Open wide /o/, wider /o/.
3. Let’s try a tongue twister on a chart: We hop on a jog in the hot pot. I’ll read it first and then we can say it together. This time we read it, let’s stretch out the o = /o/. We hooop on a joog in the hoot pooot.
4. Now let’s take
out our primary paper and pencil. We can write the letter o for the sound
o = /o/. Take your pencil and start a little under the fence, curve down to the
sidewalk, curve over and back up to the fence.(this will be modeled) Now I
want you to make five more just like it. O is the signal for you to say o
5.Call on students to tell what they knew and how they answered: Do you hear o = /o/ in fog or code? Frog or tumble?
Float or clock? Flock or lip? Let’s practice the o = /o/ sound. Every time you hear the o = /o/ sound, I want you to hold up your card. When you do not hear it, I want your card to be down. Then read: Go to the doc who’s in a fog.
6. Read: Doc in the Fog and discuss the story. Read the book a second and this time having the students hold up their o = /o/ cards when they hear the o = /o/ sound. Then write the words they hear on the board. The students will draw picture of the words and write about it using invented spelling.
7. For assessment: Give the students a picture page and have them name the pictures. Then they will circle the pictures whose names have /o/.
• Reference: Susan K. Kemp. “The Sock Hop.” www.auburn.edu/academic/education.reading_genie/illum/kempel.html
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A magnet made from a piece of steel is called a permanent magnet because, once magnetized, it keeps its magnetism. An electromagnet is a temporary magnet associated with a flowing electric current–turning off the current turns off the magnet.
A simple electromagnet consist of a length of iron, called the core, wrapped around and around with a length of insulated wire. When the ends of the wire are connected to a current supply such as a battery, the iron becomes magnetized and the whole arrangement acts just like a permanent magnet. It is not surprising that the branch of physics that deals with this interaction of electricity and magnetism is called electromagnetism.
The British scientist Michael Faraday championed this area of science in the 1830s, although the first electromagnets had been constructed a few years earlier by the American physicist Joseph Henry. There were three key stages in the scientific development of electromagnetism. The first was the 1820 observation by the Danish physicist Hans Christian Oersted that there is a magnetic field surrounding a wire carrying an electric current. He deduced this fact when he observed the deflection of a compass needle place near a current-carrying wire.
The second major step was taken about 10 years later when Faraday proved experimentally that a magnetic field that is changing induces a current in an associated circuit. The third and final stage came in the 1870s when Scottish theoretical physicist James Clerk Maxwell explained the interaction between electricity and magnetism in a set of mathematical equations. He showed that a changing electric field should produce a magnetic field and predicted the existence of electromagnetic waves that travel at the speed of light. Indeed light is such a wave, as are radio waves and all the other types of electromagnetic radiation discovered after Maxwell's time.
Simple electromagnets have limited uses, perhaps the best-known being to lift pieces of iron and steel in a scrap yard. This application demonstrates one of the great advantages of an electromagnet: it can be on to pick up scrap and then off again to dump it.
Other applications of electromagnets include dynamos, electric motors, electric bells, solenoids, and relays. A solenoid is a simple switching device, consisting of a sliding, spring-loaded electromagnet. Its movement is commonly used for opening and closing the contacts in a relay (a type of high-voltage switch).
Electromagnets are also key components in some kinds of microphones, loudspeakers and audio and video tape decks. MRI scanners and particle accelerators use some of the most powerful electromagnets in the world.
Aitken Hugh G.J. , Syntony and Spark: The Origins of Radio , New York : Wiley , 1976 Buchwald Jed Z. , From Maxwell...
This force has long been familiar to humankind. Possibly the first to learn about its properties were the Chinese, who discovered that a...
Branch of physics dealing with the laws and phenomena that involve the interaction or interdependence of electricity and magnetism . The... |
Because organic fruits and vegetables aren't treated with waxes or preservatives, they may spoil faster. Also, some organic produce may look less than perfect — odd shapes, varying colors or smaller sizes. However, organic foods must meet the same quality and safety standards as those of conventional foods.
Food safety tips
Whether you go totally organic or opt to mix conventional and organic foods, be sure to keep these tips in mind:
- Select a variety of foods from a variety of sources. This will give you a better mix of nutrients and reduce your likelihood of exposure to a single pesticide.
- Buy fruits and vegetables in season when possible. To get the freshest produce, ask your grocer what day new produce arrives. Or check your local farmers market.
- Read food labels carefully. Just because a product says it's organic or contains organic ingredients doesn't necessarily mean it's a healthier alternative. Some organic products may still be high in sugar, salt, fat or calories.
- Wash and scrub fresh fruits and vegetables thoroughly under running water. Washing helps remove dirt, bacteria and traces of chemicals from the surface of fruits and vegetables. Not all pesticide residues can be removed by washing, though. You can also peel fruits and vegetables, but peeling can mean losing some fiber and nutrients. |
Today’s blog comes to us from Dr. Patrick Dawson, ob-gyn.
1. Why is folic acid during pregnancy important?
Folate (also known as folic acid) is important in cell growth and differentiation. A growing baby needs access to adequate folate to prevent certain birth defects. We know that women who are deficient in folic acid have an increased risk of having a baby with an open neural tube defect such as spina bifida or anencephaly. It is important to know, however, that there are many reasons for birth defects, and even with enough supplementation, we cannot prevent all problems.
2. If planning pregnancy, when should women begin taking folic acid?
As folate is important for organogenesis (the formation and differentiation of cells into the various organs like the eyes, brain, heart, etc.), it is most important for the developing baby to have access to sufficient folic acid in the first few months of pregnancy. In fact, a baby would benefit if a woman began taking prenatal vitamins before she even becomes pregnant. Generally, beginning prenatal vitamins one to two months before attempting to conceive is preferred, but even if this time is missed, expectant mothers should begin prenatal vitamins as soon as the pregnancy is recognized. Folate is very important in the beginning of the pregnancy, iron is more important in the second half of pregnancy, and certain vitamins and minerals are important throughout. Generally, prenatal vitamins are recommended throughout pregnancy and are safe to take even when not pregnant.
3. Is there any difference in the amount or quality of folic acid in over-the-counter prenatal vitamins versus prescribed prenatal vitamins?
Folic acid found in over-the-counter (OTC) prenatal vitamins and prescription prenatal vitamins is usually about the same and both will have sufficient amounts to meet the minimum recommended intake, or 400 micrograms of folate. Some prescriptions will have extra, up to 1,000 micrograms, but there is no information to suggest that 1,000 micrograms is better than 400 micrograms for the average mom-to-be. (Moms who have given birth to a baby with an open neural tube defect like spina bifida or anencephaly are usually recommended to take 1,000 micrograms each day, but there is no evidence to suggest this is a better approach for all women.)
Generally, OTC prenatal vitamins suit most women perfectly well. Some are larger, some have a "fishy" smell, and some are chewable or even "gummy." What is important is to get the nutrients in, no matter whether through OTC pills, prescription or through a varied and healthy diet. Women should be encouraged to discuss any problems they are having with taking their vitamins with their doctor. There may be a better brand or type of pill that will work better for them. Some women stop taking the prescription because they are more expensive, and they are often ashamed to discuss this with their doctor. I would say this is a mistake, as there are usually cheaper options available that are just as effective.
4. If folic acid was not taken prior to pregnancy, what other sources of folic acid do we consume through our diet?
Folate is an important part of any diet, at any age. It is naturally found in many different foods, such as dark leafy green vegetables like spinach, oranges, beans and lentils. Commercially made breads (store-bought) are also fortified with extra folic acid.
5. Would there be a reason to take folic acid after childbearing years?
Because folate is most important in the month before pregnancy and the first two to three months after conception, a time when many women will not even recognize they are pregnant, a woman of childbearing years who has potential to become pregnant should consider taking a prenatal vitamin every day. This would help ensure she is taking the prenatal vitamin at the most optimum time if she were to become pregnant.
Prenatal vitamins are also important during breast-feeding and should be continued throughout this time as well. For women who have had anemia in the past, the extra iron in the prenatal vitamins may also be beneficial. In the end, prenatal vitamins can be one piece of a healthy lifestyle for women at any age, not just during pregnancy and breast-feeding.
6. What other considerations should be weighed when choosing a prenatal vitamin?
DHA and omega-3 fatty acids are important parts of brain and eye development. We think supplementation during pregnancy and while breast-feeding may promote brain and eye development, but the benefits of supplementation versus a healthy diet have not been proven. When selecting a prenatal vitamin, a woman should consider DHA supplementation, now often combined with the prenatal vitamin. Some women find this difficult, as they often have a fishy smell and/or aftertaste. This can be particularly difficult toward the end of the first trimester when morning sickness is typically at its worst. If this is a problem, choosing a prenatal without the DHA and omega-3s may be more appropriate. The bottom line is that the specific brands and the "added bonus" of the DHA/omega-3 are much less important than having a pill that is tolerable for the patient so she can keep it down each day. It is almost important that the supplement is affordable enough that she can continue taking it.
Dr. Patrick Dawson is an obstetrician-gynecologist at Southwest Medical Associates, part of the Lovelace Health System family. Dr. Dawson provides both ob-gyn services as well as high-risk OB. He is board certified and a fellow of the American Board of Obstetrics and Gynecology. To reach his office, call 505.823.1010. |
Health and the Environment
Air pollution and the Greenhouse effect are both increasing problems not only in the UK but globally. Over a period of time, experts feel that no matter what the population do to try and improve the world’s ozone layer; it will be too late as the efforts may not take effect for 100 years. This essay will explain air pollution and the Greenhouse effect, describing how air pollution affects the UK, as well as taking into consideration a health issue which has been linked to air pollution and evaluating the main theories of this link. Finally analysing global attempts made to reduce the diseases linked to air pollution.
Air pollution is defined as; ‘contamination of the atmosphere by substances that, directly or indirectly, adversely affect human health or welfare. Air pollution results from human activities, both deliberate releases (as from smokestacks) and fugitive emissions (as dust from streets), and natural sources, including sea spray, volcanic emissions, pollen etc. ’ (Liu, 2004. ) The sources of air pollution are as follows; vehicle emissions (carbon monoxide), volcanic emissions, pollen, dust, smoke, construction, CFC’s and indoor pollution, for example, paint fumes, cigarette smoke and cleaning fluids.
The Greenhouse effect takes place because the gases in the atmosphere stop some of the heat from escaping into space these gases are called greenhouse gases. The natural process between sun, the atmosphere and the earth is called the greenhouse effect because it works in the same way as a greenhouse. The windows in a greenhouse play the same role as the gases in the atmosphere, keeping some of the heat inside the greenhouse. Man-made activities also produce greenhouse gases, these are increasing, the main sources are; fossil fuels, cutting down and burning trees, and chlorofluorocarbons (CFC’s).
As more of these gases are trapped in the atmosphere the earth becomes warmer. This is known as global warming. In both developed and rapidly industrialising countries, the major historic air pollution problem has typically been high levels of smoke and sulphur dioxide arising from the combustion of sulphur-containing fossil fuels such as coal for domestic and industrial purpose. Air pollution in the UK has been a recognised problem as far back as the 13th Century, when the use of coal in London was prohibited on the ground that it was causing harm to health.
During the Industrial Revolution, smog pollution in urban areas became a significant problem, due to the industrial and domestic burning of coal. Today, both urban and rural smog pollution results from the build up of secondary photochemical pollutants such as ozone. Whilst air quality has generally improved over the last 100 years, legislative controls and the introduction of further low emission technology will help to reduce air pollution in the UK still further. Air pollution and asthma are suggested to be linked. Asthma affects more than 3 million people in the UK.
It can occur in people of any age, but it is most likely to develop in children by the age of 5 and in adults during their 30s. Asthma affects the airways and disrupts the transport of air in and out of the lungs. Sufferers have sensitive airways which become inflamed and narrowed under certain conditions. The inflammation is caused by the body’s immune system, in order to counteract the irritant. When inflammation occurs it becomes difficult for oxygen to reach the lungs. Consequently asthmatics may experience difficulty in breathing.
Numerous factors can be responsible for triggering an asthma attack. Asthmatics are usually allergic to more than one trigger and their asthma symptoms may vary from wheeziness, to shortness of breath, chest tightening or over production of mucus. Both indoor and outdoor air pollution, natural and man-made, can trigger asthma attacks. A BBC article 16 Sept 2003 showed that a study carried out in Birmingham of people living near an iron foundry found that the number of patients admitted to hospital with asthma fell by 30% after the foundry cut emissions.
There is a growing debate on whether there is a link between air pollution and asthma. A number of studies have suggested a link, others have not. For instance, according to the article ‘asthma rates have soared in Britain since the introduction of the clean Air Act 1956, which significantly cut air pollution across the country. A spokeswoman for The National Asthma Campaign said ‘Many asthma sufferers say pollution triggers their asthma. ’ ‘However, there have been very few specific studies which have shown that air pollution causes asthma.
It is difficult to prove. ’ (BBC Health online (16th Sept 2003)). Adrian Bauman (1996) suggested that epidemics of asthma may yield clues to causal agents. A report of an epidemic in east Birmingham 1987, showed that between 14 September and 7 October, 86 children meeting the case definition of asthma (reversible wheeze, reversible dyspnoea, or tachypnoea with wheezing) were admitted to Birmingham Heartlands Hospital, a rate 3. 58 times higher than that in the preceding four weeks and 3. 4 times higher than that in the same period of 1986.
Local meteorological data and pollution data for the period 1 August to 5 October showed that the largest single fall in mean air temperature between days (3. 9°c) occurred on 13 September, the day before the start of the increase in admissions; it was accompanied by reduced humidity and increased barometric pressure but no rain and no relevant changes in monitored pollution levels. Another example of air pollution being linked to asthma was reported on 12th March 1999. When evidence found the link to children and asthma.
Experts tested 632 children’s breathing aged 7-11 years. They found that respiratory disorders worsened as air pollution increased. The children were split into four groups; Bronchial hyper-responsiveness, Allergies, neither and both. Both children from rural and urban areas were asked to keep a diary of their symptoms and tested their lung capacity 3 times a day. Data was collected from 459 children, it showed that 119 had bronchial hyper responsiveness and allergies when air pollution was high; therefore they were more likely to suffer asthma related problems.
When there were more particulates – pollutants larger than 10 micrometers – in the air, these children were up to 139% more likely to suffer, and when there were more of the pollutants that make up car exhaust fumes – black smoke, sulphur dioxide and nitrogen dioxide – they were up to 131% more likely to have such symptoms. (BBC health online (1999)). Although there is evidence to suggest that air pollution does worsen asthma, Douglas Carnall (1995) argues that there is no good evidence to suggest this… he says ‘Current levels of air pollution play only a small part in exacerbating existing asthma.
He continues ‘Epidemiological surveys show no association between the prevalenceof asthma and areas with higher levels of airpollution, butfive studies have shown a moderate and consistent correlationbetween asthma and exposure to traffic. It is possible; however,that social class and reporting bias may have confounded theseresults. ’ There are a greater number of studies shown to link asthma and air pollution than there is to prove it has no effect, the main theories to suggest that asthma is on the increase all relate to 3 main factors; Genetic, environmental and allergenic factors.
The genetic theories of asthma attempt to explain asthma as a genetic/inherent condition. Lebowitz (1984) argues that children with asthmatic parents are more likely to inherit the condition than those with non-asthmatic parents. The environmental theory says the effects of air pollution are diverse and numerous. Contamination of the atmosphere by man made and natural pollutants has led many to suggest that the rise in asthma positively correlates with the release of pollutants into the atmosphere.
Allergenic factors relates to the different triggers that affect asthma sufferers, these vary depending on the time of year, weather and other allergies. The main theories to link air pollution and asthma is pollutants, such as solvent aerosols, air-borne chemicals (sulphur dioxide etc) and air-borne organic compounds, for example pesticides. The London Smog Disaster occurred in December 1952. London experienced a cold period therefore a large amount of coal was burnt resulting in smoke bellowing from the chimneys.
Light winds and moist air were the ideal condition for fog, which thickened and lasted for a few days, this mixed with the smoke and soot, causing the smog disaster. In central London the visibility remained below 500 meters continuously for 114 hours and below 50 meters continuously for 48 hours. Road, rail and air transport were brought to a standstill. The smoke laden fog that covered London brought the premature death of an estimated 12. 000 people and illness to many others.
The deaths which resulted from the smog can be attributed primarily to; pneumonia, bronchitis, tuberculosis and heart failure. It was reported that people with bronchitis and asthma died in their beds from suffocation because of the smog. The death rate remained above normal through the winter and was still 2 per cent up the following summer. In the weeks that followed, the medical services compiled statistics and found that the fog had killed 4,000 people—most of whom were very young or elderly, or had pre-existing respiratory problems.
Another 8,000 died in the weeks and months that followed. This disaster was enough evidence to suggest that air pollution does cause illness or even death. It was in 1956, the Clean Air Act was introduced, it was directed at domestic sources of smoke pollution – authorised local councils to set up smokeless zones and grants were introduced to encourage householders to convert from coal fire to smokeless coal to electricity. In 1991 London experienced a repeat of the 1952 smog this caused an extra 160 deaths for the time of year.
In 1968 the Clean Air Act; tall chimneys was introduced, this Act brought in the basic principal for the use of tall chimneys for industries burning coal, liquid or gaseous fuels. The problem with this Act was the scrubbers/filters which absorbed the chemicals had to be disposed of into landfill sites, therefore the chemicals were been out back into earth, eventually seeping through the soil and back in to the atmosphere. 1St January 1989 saw the introduction of the Montreal Protocol.
The main aims of this protocol was to get whole countries legally bound to reduce and eventually phase out all together the use of CFC’S, also to decrease the use of chemical compounds destructive to the ozone in the stratosphere by 50% by the year 1999. As scientific of the processes of chemicals that destroy the ozone layer has grown, the number of countries signing the protocol had increased to 96 by 1996. In the meantime, several amendments have been made. (Ashton. J, Laura. R (1999) pp 28. ) The Kyoto Protocol became a legally binding treaty on 16th February 2005.
It could only come into force after two conditions had been fulfilled, these were; It had been ratified by at least 55 countries and it had been ratified by nations accounting for at least 55% of emissions. The two main countries which have not ratified are Australia and USA; this is because the countries leaders believe that lowering their emissions will affect the economy of the country. The main aim of the Kyoto Protocol is to make countries cut their emission levels by various percentages depending on the country.
The UK has committed itself to a 12. 5% reduction, although it has already set its own domestic target of a 20% reduction in carbon dioxide by the year 2010. Whilst the Kyoto protocol is a very good attempt to reduce emissions, there has been a significant change in emission levels but until America and Australia agree to it there will never be any improvement in the ozone layer as these 2 countries are the biggest polluters in the world. Therefore no matter how many Kyoto protocols there are, the ozone layer will never be completely regenerated. |
Oysters usually begin reproducing in the spring as waters are beginning to warm and phytoplankton becomes more prominent in the water. Sperm and eggs get ejected into the water column in large numbers where fertilization occurs. The fertilized egg quickly develops into a swimming oyster larvae. Within just 24-48 hours the larvae develops a thin shell and starts eating algae, though it is far from looking like a mature oyster.
Roughly two weeks later the larvae have developed enough to settle to the ocean floor and find a comfortable spot on hard substrate (usually other oyster shells, creating reefs). This is when the oyster takes on a more recognizable form. During this stage oysters are referred to as “spat.” Most oyster farmers order spat or “seed” from hatcheries to grow into adult oysters.
Oysters are filter feeders, which means that they eat by filtering seawater with their gills, separating out the nutritious phytoplankton and expelling the rest of the waste as pseudo-feces. Maine is an excellent place to grow oysters because the Gulf of Maine is famous for its clean and nutrient-rich waters. An adult oyster can filter roughly 50 gallons of seawater a day!
Why do oysters from different locations have distinct taste?
Because oysters are filter-feeders, they acquire the flavors of the sea in which they grow. To connoisseurs this is described as the oysters' merroir. The merroir is determined by any number of environmental characteristics such as the water's salinity, minerals in the sediment, the amount of seaweed in close proximity, or what type of phytoplankton they have been filtering. The same species of oyster can vary greatly depending on where it is grown and how it is raised. |
Many languages can be difficult to learn, and may be even more confusing when regional accents enter the mix. There is one language, however, that requires no sound at all, and because of that fact, it is a tremendously versatile and accessible method of communication. American Sign Language (ASL) is one of the best resources available for those afflicted with deafness and those with whom they communicate.
The origins of sign language may be traced back as far as the 5th century B.C.E. It developed freely around the world, though most recorded proof of sign language has been found in 17th century Europe. Different groups of people had their own understood methods of communication through hand signs, such as the development of British Sign Language (BSL) by Thomas Braidwood. ASL, however, actually grew from a merger between two different countries.
In the 1700s, there was a high level of hereditary deafness in the community of Martha’s Vineyard. To better communicate, residents developed a rudimentary sign language that was used by deaf and hearing people alike. Unfortunately, this creative resource was restricted to the island, and no formalized training or resource yet existed for those who became deaf through sickness or injury. That all changed when, in the early 1800s, young Thomas Hopkins Gallaudet befriended and began working with his neighbors, the Cogswell family, to help develop a way to educate their nine year-old daughter, Alice, who had become deaf as a result of spotted fever. Her father, Dr. Mason Fitch Cogswell, agreed, together with Gallaudet, that there desperately needed to be a system for the education of the deaf.
Gallaudet travelled to Europe to research existing systems for the deaf, and in London, he came across the French abbé and instructor Roch-Ambroise Cucurron Sicard, who invited Gallaudet to visit the Institut National de Jeunes Sourds de Paris (INJS), a school for the deaf founded by Charles Michel de l’Epée. Due to rapidly decreasing funds, he was unable to stay for very long, and so brought one of Sicard’s students, Laurent Clerc, back to the United States. The two exchanged information, tutoring one another in French Sign Language (LSF) and written English, and began raising money for the new school. The doors to the American Asylum for the Instruction of Deaf and Dumb Persons opened on April 15, 1817, with Alice Cogswell as the first student.
Clerc used the basics of LSF for teaching, but he soon noticed that his students, many of them from Martha’s Vineyard, were altering the signs or using the Martha’s Vineyard system. This new fusion of LSF and the Martha’s Vineyard system became known as ASL, and quickly spread outside the classroom for use in daily life and in the home. To this day, ASL shares many similarities with LSF and is largely incompatible with BSL.
Complete proficiency in ASL is measured by a series of four levels, or courses, which the student must complete in order:
ASL does not follow traditional English grammar rules, and the meaning of many words change, according to an additional movement or their location within a sentence. The location of the sign with respect to the body is also critical for comprehension. For example, the words “girl” and “remember” have the same hand sign, but are performed in a different location in space.
In ASL, the letters of the alphabet are represented by different hand signs, which may be formed with only one hand. Only two letters, J and Z, require any sort of movement. There are actually only 22 different signs for the alphabet – the complete 26-letter set is achieved when signs are placed differently in the air or, as with J and Z, accompanied by a certain motion. Fingerspelling, or the process of forming words with these alphabet hand signs, is frequently used to clarify names, brands, or different members of a larger group (such as “daffodil” rather than “flower”). The same holds true for numbers, which consist of ten different hand signs, all of which can be made with one hand.
As mentioned before, the syntax of ASL differs from regular English in that sentence structure begins with the subject, followed by a predicate. Words like “is” and “am” are frequently substituted with a nod of the head, to allow for efficiency of communication. For longer sentences, it is also acceptable to put a direct object either after the verb or before the subject, according to your preference. Indirect objects are placed after the subject, and followed up with the action of the sentence. Sentence structure can be difficult to master, but ASL as a language is quite flexible, and the more frequently you practice, the better you’ll become.
To become an ASL interpreter, you must first be proficient in ASL itself. This is usually achieved by means of a course, whether on a campus or online. Many courses emphasize in-person practice with another ASL signer, to assist with practice. Due to the demands of an interpreter’s job, it is generally desirable to have as large a vocabulary as possible. To become an official interpreter once skilled in ASL, there is an exam provided by the Registry of Interpreters for the Deaf. The exam is rigorous, but once passed, the student earns a National Interpreter Certification (NIC), with which they may begin working as an ASL interpreter.
Phrasing in ASL relies on the magnification or exaggeration of certain words. For example, to convey the phrase “very happy”, a signer might use the hand signal for “happy” and modify it with a more exaggerated movement and a pause during the first portion of the hand signal. Adverbs in ASL may be produced this way, by adding simple inflection on existing words. Facial expressions also play a key role in providing a tone for the communication. Human facial expressions are universal, and it is difficult to mistake the disgust of a stained shirt when the hand signs are accompanied by a grimace.
ASL is a remarkably versatile language, and quite fun to learn. For more information on ASL, its structure, and how to learn it, please feel free to review the additional resources below.
Life Print – ASLU
American Sign Language Browser
Signing Savvy Online Dictionary
History of Sign Language
Sign Language Linguistics
American Sign Language Alphabet & Number Chart
History of American Sign Language
Deaf Culture – Sentence Structure
Master American Sign Language
Is Sign Language the Same All Over the World?
American Sign Language Alphabet Practice
ASL Grammar & Basic Linguistics |
Dürer is the greatest of German artists and most representative of the German mind. He, like Leonardo, was a man of striking physical attractiveness, great charm of manner and conversation, and mental accomplishment, being well grounded in the sciences and mathematics of the day. His skill in draughtsmanship was extraordinary; Dürer is even more celebrated for his engravings on wood and copper than for his paintings. With both, the skill of his hand was at the service of the most minute observation and analytical research into the character and structure of form. Dürer, however, had not the feeling for abstract beauty and ideal grace that Leonardo possessed; but instead, a profound earnestness, a closer interest in humanity, and a more dramatic invention. Dürer was a great admirer of Luther; and in his own work is the equivalent of what was mighty in the Reformer. It is very serious and sincere; very human, and addressed the hearts and understanding of the masses. Nuremberg, his hometown, had become a great centre of printing and the chief distributor of books throughout Europe. Consequently, the art of engraving upon wood and copper, which may be called the pictorial branch of printing, was much encouraged. Of this opportunity Dürer took full advantage. The Renaissance in Germany was more a moral and intellectual than an artistic movement, partly due to northern conditions. The feeling for ideal grace and beauty is fostered by the study of the human form, and this had been flourishing predominantly in southern Europe. But Albrecht Dürer had a genius too powerful to be conquered. He remained profoundly Germanic in his stormy penchant for drama, as was his contemporary Mathias Grünewald, a fantastic visionary and rebel against all Italian seductions. Dürer, in spite of all his tense energy, dominated conflicting passions by a sovereign and speculative intelligence comparable with that of Leonardo. He, too, was on the border of two worlds, that of the Gothic age and that of the modern age, and on the border of two arts, being an engraver and draughtsman rather than a painter. |
First 237 words of the document:
Enzymes in Digestion
When you eat food it is mostly made up of large insoluble molecules that your body cannot absorb
straight into the blood stream so they need to be broken down or digested into smaller, soluble
molecules that can be absorbed into cells.
Digestive enzymes (unlike normal enzymes) work outside the cells of the body and are produced by
specialised cells found in glands (like the salivary glands and the pancreas) and in the lining of your
gut. They get mixed up with the food in the gut and break them down.
The gut does 3 main things to aid digestion...
1) Helps break up food into smaller pieces with a large surface area for enzymes to work on.
2) Mixes food with digestive juices so enzymes come into contact with as much food as possible
3) Moves food from 1 area to the next
Enzymes that break carbs down are called carbohydrases. Starch is the most common carb an is
broken down into sugars like glucose. The reaction is catalysed by amylase. It is produced in the
salivary glands (meaning digesting starts in your mouth) but is also found in the pancreas and small
intestine. No digestion takes place in the pancreas as all the enzymes made there go to the small
intestine, where most the start is digested.
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Proteins are found in fish, meat and cheese and are broken down into amino acids. It is catalysed by
protease enzymes. They are produced from the stomach, pancreas and small intestine. The
breakdown takes place in the stomach and small intestine.
Lipids (aka fats and oils) are broken down into fatty acids and glycerol. The breakdown takes place
in the small intestine. It is catalysed by lipase enzymes which are made in the pancreas and small
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Once food is broken down into soluble molecules they leave the small intestine and pass into the
blood supply to be carried to cells.
Using the digested food
Glucose is used by the cells in respiration.
Fatty acids and glycerol may be used as a source of energy to build cell membranes, make
hormones and as fat stores.
The amino acids build the proteins your cells need. This protein synthesis takes place on the |
The school uses the “Letters and Sounds” scheme to teach phonics in Nursery, Year R, Year1 and Year 2.
(The sounds that are taught at each phase can be found at http://www.letters-and-sounds.com/).
The children develop their skills in phase one of letters and sounds, which involves seven aspects:
Aspect 1: General sound discrimination – environmental sounds
Aspect 2: General sound discrimination – instrumental sounds
Aspect 3: General sound discrimination – body percussion
Aspect 4: Rhythm and rhyme
Aspect 5: Alliteration
Aspect 6: Voice sounds
Aspect 7: Oral blending and segmenting
These are taught through regular, planned opportunities to listen carefully and talk extensively about what they hear, see and do. Furthermore, children experience the above aspects through their day to day exploration of the nursery stations, which have been deliberately designed, initiated by the children's current interests and learning.
Children who show a strong understanding and ability within phase 1 will be targeted to access small group phonic session that will introduce phase 2 letters and sounds. Children who are learning at a phase 2 level will also begin to take home a reading book at the beginning stage (lilac) and will progress through the reading scheme as appropriate.
Year R, Year 1 and Year 2
All children from Year R to Year 2 receive daily 30 minute phonics lessons. The pupils begin Reception ready to start learning the sounds needed to blend and segment words and leave Reception ready to begin phase 5, which focuses on more complex and alternative sounds. At the end of Year 1 pupils take the National Phonics Screening Check to ensure they are confident applying their phonics skills and are ready to begin learning phase 6 which requires the teaching of suffixes, prefixes and spelling rules in Year 2.
Parents can help support their children's phonic development by encouraging children to use their phonics to sound out unfamiliar words.
Parents can also support their children to apply their phonics when writing, by encouraging children to slowly sound out words verbally, then writing down the sounds they can hear.
http://www.phonicsplay.co.uk is a great website which contains online games and activities to print to support your child’s phonics development. |
There are a number of conservation laws in physics, and these are well-enough established to be pretty basic. Conservation of energy, momentum, angular momentum and mass are critical to the way the universe operates. But what do these laws mean?
Let’s start with the conservation of energy, ignoring for the moment the fact that under certain limited conditions it is possible to transform a very small amount of mass into a very large amount of energy, and vice versa. That’s nuclear energy, and we’ll get to it in another post.
Conservation of energy states that while energy can be changed from one form into another, the sum of all forms of energy is unchanged—energy can neither be created not destroyed.
Wait a minute, you may be saying. What about burning wood in my fireplace? Isn’t that producing energy?
It’s producing heat energy, yes—but the heat energy produced is balanced by the fact that the unburned wood has more chemical energy than the ash left behind in the fireplace. A very exact measurement, including the heat and light of the fire, the motion of air that it produces, and the increase in thermal energy of the fireplace itself, the smoke, and our hands held out to the fire, would show that the energy produced by the fire would be exactly the same as the chemical energy lost by the wood as it turned to ash.
Chemical energy, light and heat are by no means the only forms of energy. Two very important ones are gravitational potential energy and kinetic energy—the energy of any moving mass. If we think of a ball released on top of a hill, part of the gravitational potential energy of the ball will be transformed into the kinetic energy of its motion as it rolls faster and faster down the hill. Part, because part will be transformed into friction, both of the air and against the ground, which will ultimately reappear as heat.
Another form of energy with which we are very familiar is electrical potential energy. Electrical energy is convenient because it can readily be distributed by wires, but there is some heating of those wires and radiation of electromagnetic energy in the process, and thus a loss of electrical energy as heat. But the source of most of the electrical energy we use today is either chemical energy (fossil fuel or biofuels) or gravitational potential energy (hydropower.) Direct solar energy (energy of sunlight, or more correctly electromagnetic radiation) wind power (kinetic energy of the air) tidal energy (left over from the gravitational potential energy which created our solar system) and geothermal energy (generated by nuclear reactions in the Earth’s core) produce only a relatively small fraction of the electricity generated.
The point is, energy is not generated out of nothing. It is transformed from some other form of energy. Both biofuels and fossil fuels get their chemical energy from solar energy—the only difference is whether the solar energy is what is falling on the earth today or is stored solar energy from the distant past. Hydropower and wind energy are also driven by the sun.
In my science fiction book, abilities such as teleportation are subject to all of the conservation laws. When Derik asks Roi what he has to do for a balanced teleport to a higher elevation, Roi replies, “Move mass down to balance my mass moving up, same as levitation. The distance down times the mass I move down has to be the same as my mass times the distance I move up.” In this case, simple conservation of gravitational potential energy. But that’s not all he has to remember! |
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High schoolers view a classic western movie and discuss what icons are. They then watch another movie and focus on different parts of the film. They create a presentation to show their findings.
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The International Geophysical Year was designated as a major international effort of the world’s scientists to gather and share data on the Earth’s natural phenomena. The 1957-1958 year was selected because scientists desired to coordinate worldwide observations during this known period of maximum sun-spot activity. More than 10,000 scientists from 67 countries participated in a program in which 2,500 IGY stations were established throughout the world. Data collected covered a wide variety of disciplines that included geology, oceanography, glaciology, meteorology, seismology, geomagnetics, and ionospheric, auroral and outer-space phenomena.
The IGY was the largest and most important international scientific effort to that date. One of its many later ramifications was the setting aside of Antarctica as a nonmilitary region to be used for international scientific purposes alone. The IGY was the first worldwide scientific effort to involve Antarctica, owing to rapid advances in logistics and technology that enabled these activities to be undertaken on the southern continent. The Antarctic was recognized as a region of profound interest and unique characteristics. It was considered as having potential for geophysical information regarding the impact of its huge ice mass on global weather and the oceans, as well as the nature of the aurora australis and the ionosphere over the ice during the long Antarctic winters.
The South Pole, site of the United States’ Amundsen-Scott Station became the terminal link in important Pole-to-Pole observations along three meridians. A weather station at Little America analyzed reports from aircraft, trail parties, outlying stations, whaling fleets, and nearby countries.
The IGY activities in Antarctica contributed significantly to knowledge of the physical character of the earth and its weather, the ionosphere, and outer space. Much new knowledge of the Antarctic ice sheet was gained from drilling cores and from inland traverses that gathered data on ice temperatures, density, thickness, ice-surface elevations, and magnetic and gravity fields.
IGY in Antarctica was an outstanding success,characterized by complete cooperation between nations in the gathering, analyzing and exchange of data. The international program of allowing all nations working in Antarctica to place scientific stations anywhere, despite prior sovereignty claims, led directly to the eventual formulation and success of the Antarctic Treaty of 1961. |
There are many reasons why it is important to be able to identify farm animals, horses and small companion animals. Unique identification marks are essential for ensuring the correctness of breeding programmes, for preventing the spread of disease and for eliminating the possibility of deceit in competitions or when animals are sold. The traditional method of marking larger farm animals relies on branding with hot irons or on ear-tagging but this is deemed inappropriate for use on dogs and cats, which are identified by the implant of a microchip transponder. Until recently, horses were generally branded but following concerns that the practice is unnecessarily cruel there has been a gradual switch towards the use of microchips. Branding has essentially been discontinued in the European Union, although several countries still accept it and breed registries claim that this traditional method is perfectly satisfactory and obviates the need for costly equipment.
Comparisons between the two methods for marking horses have focused on how they are perceived by the animals: does either method cause more stress or more harm to the horse? Surprisingly, however, no attention has been paid to the other side of the coin. There is no doubt that microchips can be unambiguously decoded, providing the necessary equipment is available, but how well can brand marks be read? The issue has now been examined by Jörg and Christine Aurich of the University of Veterinary Medicine, Vienna.
Brands on horses generally combine a symbol to indicate the particular breed with a two-digit number to identify the individual animal. To assess the readability of the markings, the researchers asked three experienced people to record the brands of about 250 horses participating in an equestrian tournament in Germany. All three testers were able to recognize the breed symbols on about 90% of the animals and for about 84% of the animals the symbol was recorded correctly by all three people. However, the situation for the two-digit numbers was dramatically different. While each of the three readers read the numbers correctly on about half of the horses, the correct number was recorded by all three of them for less than 40% of the animals.
To assess the legibility of brand marking under 'ideal' conditions, the researchers examined the markings on 28 horses that had been euthanized, in each case for reasons not related to branding. Surprisingly, the brand marks could be clearly identified on only nine of the animals, while for six horses neither the brand symbol nor the two-digit number could be deciphered even after the site of branding (generally the left thigh but in two cases the left side of the neck) had been shaved. This finding confirmed the unreliability of marking horses by branding. At the same time, the researchers naturally examined the sites where the horses had been branded for evidence of tissue damage. Nearly all of the horses had histological changes at the branding sites, consistent with having experienced a third-degree thermal injury.
Jörg Aurich sums up the results concisely. "Branding is clearly associated with local tissue damage and the markings are often insufficiently clear to be decoded, even by experienced observers or after the horse has died. There really isn't any reason to continue to mark horses in this outdated way."
Explore further: The mark of the beast: tradition or stress? |
Surface irrigation is arguably the least complex form of irrigation. At its simplest, no attempt is made to stop fields from naturally flooding. In general, this is only suitable in situations where the crop is of little value, or where the field will be used only for grazing or even recreation. Of course, while this method is simple and easy, it is totally dependent upon a suitable water source.
A more refined variation, though still reliant on a plentiful supply of water, is basin irrigation. Closely-spaced crops with deep roots are particularly suited to this method, and the growing of rice in paddy fields is an example familiar to most of us. The basin referred to is simply a field, enclosed with a raised bank, or dike, to contain the water. The water is directed into the field by various channels and pipelines, or may even be brought in manually. Two extremely old methods use these devices:
By whatever method, the water is transported to the channels where it floods the field, causing a deep layer of mud to form in the bottom of the basin. In the case of rice, fresh seedlings are planted in this rich and fertile mud, and in September or October the mature rice is harvested, dried and stored.
Border irrigation is similar, but in this case the field is not entirely enclosed by a dike. Instead, it is watered from one end and allowed to drain from the other. Border irrigation works well with sloping land, as does furrow irrigation, in which the water is further controlled by the use of channels within the field itself. Water is directed along these channels, and by controlling the flow of water into each channel, the farmer can control the amount of water in different portions of the field surface.
Next, we'll find out about overhead irrigation methods. |
Creating a Webquest
A WebQuest, originally developed by a team at San Diego University, is a guided online, inquiry-oriented student activity typically consisting of six parts (sometimes the process and resources, and the evaluation and conclusion are combined):
- The Introduction orients students and captures their interest.
- The Task describes the activity's end product.
- The Process explains strategies students should use to complete the task.
- The Resources are the Web sites students will use to complete the task.
- The Evaluation measures the results of the activity.
- The Conclusion sums up the activity and encourages students to reflect on its process and results.
Adapt WebQuests to your own needs
Don't have time to create your own webquest? Visit the following website to learn how to adapt the best components of other peoples webquests, fix links, and customize the content for your classroom.
Find more WebQuests
I would google your topic with keywords like "Evolution WebQuest" or visit the sites below:
QuestGarden (Pay a small fee for a two year subscription) |
The comma is the most abused punctuation mark. Writers are sometimes so worried about following rules that they forget to pay attention to the way the words sound when spoken. Commas help a reader understand the rhythm of the sentence. If you are having comma problems, say your sentence out loud and listen for natural pauses. The function of a comma is to make the reader pause. The omission of a comma can cause phrases and clauses to crash into one another, thereby confusing the reader.
Commas can influence the meaning of your sentence. Consider the following:
The food tastes terrible, however the cook fixes it.
The food tastes terrible, however, the cook fixes it.
In the first sentence, the food tastes terrible no matter how the cook fixes it. In the second sentence, the food is bad but the cook improves the taste. Again, the comma controls the meaning.
RULES FOR COMMAS
1. Use a comma to separate two independent clauses connected by and, but, or, nor, for.
Bob was usually a quiet man, but he screamed upon entering the room.
The strange man lying under the table appeared to be dead, or just possibly he was only napping.
If the independent clauses are short, you may omit the comma.
The man was still and his foot was bleeding.
His hat was on but his pants were off.
2. Use a comma to separate elements in a list or series.
Bob tried to breathe, to keep from fainting, and to remember his first aid.
Next to the man were a bassoon, a water balloon, and a raccoon.
3. Use a comma to separate introductory phrases and clauses from an independent clause that follows, particularly if the phrase or clause is long.
After catching his breath, Bob squatted next to the man and took his pulse.
When he felt nothing, Bob picked up the bassoon and blew.
Although he had never played a bassoon before, he somehow managed to make beautiful music.
Again, if the introductory phrase is short, you may omit the comma:
When he stopped playing it was dark outside.
4. If the introductory phrase is a gerund, participial, or infinitive phrase, use a comma even if the phrase is short. Otherwise, the reader may be confused:
When Bob began to eat, rats ran across the carpet.
NOT: When Bob began to eat rats ran across the carpet.
5. In a series of adjectives, use a comma if the adjectives could also be separated by and.
The nimble, fat, and furry raccoon began to poke at the water balloon.
(Could be written as: The nimble and fat and furry raccoon…)
If the and doesn’t fit, leave out the comma:
The man’s white cotton shirt was balled up in a corner.
(Would not write as: The man’s white and cotton shirt . .)
If this rule seems confusing, read the sentence aloud. If you make a slight pause between adjectives, put in commas. Otherwise, leave them out. Another test: if you can change the order of the adjectives, insert commas. For example:
The handsome, brilliant scholar
Or: The brilliant, handsome scholar
The frilly party dress
Not: The party frilly dress
6. Use commas to set off clauses, but do not use commas for restrictive clauses. An essential or restrictive clause is one that can’t be left out of a sentence. Clauses that don’t define can be lifted from the sentence without changing the meaning. Look at these sentences:
Bananas that are green taste tart.
That are green defines which bananas we mean. We cannot remove it.
Bananas, which grow in the tropics, do not need refrigeration.
Which grow in the tropics refers to all bananas. The clause can be lifted from the sentence without changing the meaning.
Let’s look at a sentence that you could punctuate either way, depending on the meaning:
The men who were tired and hungry began eating sardines.
who were tired and hungry is a defining clause, telling us which men we mean.
The men, who were tired and hungry, began eating sardines.
who were tired and hungry describes all of the men and doesn’t differentiate these men from other men who weren’t tired and hungry.
7. Commas should set off words or phrases that interrupt the sentence.
Now then, let’s get down to work.
“Save me,” he said, before falling down the stairs.
On the other hand, error can lead to revelation.
What the candidate promised, in fact, is impossible to achieve.
Hello, I must be going.
8. Use commas to set off an appositive. An appositive is a noun or pronoun that explains or identifies the noun that precedes it.
Mrs. Daniels, my favorite teacher, is wearing a wig.
Ralphie, the president of the student council, is on probation.
9. Commas go inside quotation marks, never outside:
“I do like the taste of chocolate,” she said, “but I am allergic.”
Using commas correctly is one way to make your writing clear. Reading your sentences aloud is a good way to find the natural place for commas, as is inspecting your sentences for ambiguity or confusion. |
Newly released captives on board HMS London
This photograph shows a group of African people enslaved as part of the East African trade. This group were freed from slavery by the Royal Navy in 1882. HMS London was the Royal Navy's depot ship at Zanzibar in the 1880s. At that time the Navy was active in trying to stop illegal trade in enslaved Africans in the British colonies, and tried to deter other countries from continuing the trade. The newly liberated Africans shown had probably been released from slaving ships operating between Zanzibar, the Arabian Peninsular and Asia. This trade continued until the late 19th century. Although the British had stopped trading in enslaved people earlier in the century, they still bought goods produced by them, particularly cotton from the United States until the end of the American Civil War in 1865. |
If you’re unsure about your stance on stingrays, we don’t blame you. They’re often portrayed as deadly, cold-blooded creatures who wield their venomous tails like a murder weapon. They're also oddly adorable. The best way to form an opinion is by learning a little more about the mysterious stingray. Here are 10 facts about these saucer-like creatures of the deep.
1. STINGRAYS ARE FISH.
2. STINGRAYS ARE CLOSELY RELATED TO SHARKS.
Stingrays and sharks belong to the same group of cartilaginous fish. This means that instead of bones, they’re supported by skeletons of cartilage. Like sharks, stingrays use sensors called ampullae of Lorenzini to sense the electrical signals emitted by their prey. These sensors are located around their mouths, and they compensate for the stingray's poorly-placed eyes.
3. STINGRAYS HAVE BEEN AROUND FOR A LONG TIME.
Fossil records of the first rays date back to the Lower Jurassic Period (about 150 million years ago). By the Paleocene Era just 100 million years later, all major taxa of rays had been established. Stingray fossils are hard to come by due to their lack of bones, and some of the only evidence they’ve left behind are scales and teeth.
4. STINGRAY VENOM WAS USED AS AN ANESTHETIC.
While painful, stingray venom isn’t usually deadly unless victims are stung in the chest or abdomen. In ancient Greece, venom was actually extracted from stingray spines for the purpose of being used as an anesthetic by dentists.
5. THE BIGGEST STINGRAY WEIGHS NEARLY 800 POUNDS.
Short-tailed stingrays, known as Dasyatis brevicaudata, are found off the southern coasts of Africa and Australia. They can reach 770 pounds in weight and grow 14 feet in length. The giant freshwater stingray (Himantura chaophraya) grows to be quite monstrous as well. In March, fisherman in Thailand’s Mae Klong River caught a 14-foot stingray that weighed between 600 and 800 pounds. It was one of the largest freshwater fish ever captured.
6. STINGRAYS AREN'T NORMALLY AGGRESSIVE.
While a run-in with a stingray has the potential to be deadly, they normally act kind and gentle around humans. It’s only when a stingray feels threatened that divers have a reason to worry. Most stingrays attack when a diver is swimming directly over or in front of a ray, blocking its escape route. Accidentally stepping on a ray in shallow water is also a fast way to get stung. Expert divers shuffle their feet when entering the ocean to avoid stepping directly on a stingray’s back.
7. STINGRAY JAWS CAN CRUSH MOLLUSK SHELLS.
Even though they’re cartilaginous, stingray jaws are strong enough to crush rock-hard clam shells. The calcified cartilage in their jaws is several layers thick, and the softer cores of their jaw elements are supported by hollow, mineralized struts. This makes stingray jaws strong and lightweight at the same time.
8. SOME STINGRAYS MOVE LIKE A WAVE, OTHERS LIKE A BIRD.
9. STINGRAYS ARE GOOD AT HIDING.
Next time you go for a walk through the ocean’s shallow waters, remember that stingrays spend most of their time hiding in the sand. Their mottled skin, ranging from a light sandy tone to a dark brown, gives them the perfect camouflage for chilling out on the sea floor until a tasty meal comes their way. It also keeps them hidden from predators of their own like killer whales and hammerhead sharks. To add an extra element of protection, stingrays will stir up sand with their wings while burying themselves head-first.
10. STINGRAYS ARE BORN FULLY-FORMED.
When baby stingrays are born they look like miniature versions of their parents. They are fully-proportioned and naturally good swimmers from birth. This helps them find food on their own right away, though mothers still stick around to provide protection until around age three or so. Did we mention they also look like adorable raviolis? |
By Alyssa Casey
In the United States, the National Gardening Association educates students about the health benefits of eating plant-based food through a variety of publications written specifically for school communities. Resources such as Botany on Your Plate: Investigating the Plants We Eat and Nourishing Choices: Implementing Food Education in Classrooms, Cafeterias, and Schoolyards provide innovative plans and tools for bringing plant and nutrition education into the classroom, as well as connecting children to their local food economy.
Botany on Your Plate offers a series of life science classroom lessons targeted specifically at grades K-4. Each lesson studies a different category of plant, such as fruits or flowers, or a different plant part, such as roots or leaves, with the aim of helping children develop a well-rounded knowledge of many edible plants. Students work in pairs or groups studying, dissecting, and recording observations about the plants, while teachers explain the functions of each plant part as well as the nutritional benefits that the plants can offer. The lessons also suggest plant-based snack items to feed students, exposing them to foods they may never have tried.
Botany on Your Plate incorporates diverse educational subjects into its lessons. Students enhance language and writing skills by learning plant vocabulary and journaling about observations and tastings. They gain scientific understanding when learning plant parts or thinking about a plant’s role in the ecosystem, and explore artistic skills when drawing and labeling plant diagrams. Each lesson offers step-by-step instructions and suggestions for tailoring activities to different skill levels. The book also contains a master list of supplies and produce for each lesson, a collection of plant diagrams and nutrition labels, and a glossary of terms that students can learn.
The second publication, Nourishing Choices, takes a broader approach, highlighting projects and procedures for bringing food, nutrition, and plant education into schools on a larger scale. From initial assessments, to the integration of food education into curricula, to the addition of healthier options in the lunchroom, the publication serves as a roadmap for schools and school districts. The abundance of ideas allows school communities to select programs that fit their size, scope, and needs. Profiles of successful projects around the country—including school garden programs, field trips to local farms, and even school food labs where students actually prepare lunch—offer ideas and advice to communities that are just beginning to implement food education programs. |
A trial is where two people or groups of people argue in a court.
In a criminal trial, there is a prosecutor and a defendant. The prosecutor works for the government and tries to prove that the defendant committed a crime. It often takes a long time to get a trial scheduled as the courts can be very busy. In the United States, Federal court can take up to 10 months to get a court date.
The judge contols the courtroom. He or she decides who speaks when, and they decide what evidence and arguments can be used. Sometimes, a jury is brought in to determine whether the defendant is guilty or not guilty. If there is no jury, the judge decides whether the defendant is proven guilty or not. If the defendant is proven guilty of the crime, the judge will decide the punishment, which is also called the "sentence". If the crime is serious, the defendant may go to prison or, in some countries, be executed. For smaller crimes, there is often a fine—money that must be paid, in addition to having a criminal record.
Trials are different in places where the laws are different. Different countries, cities and states all have different laws that change how trials happen. Trials in some places are very short. In some places, however, important trials can take as long as a few years while the two sides gather information and put together their arguments. |
The sensitivity of the human eye to light of a certain intensity varies strongly over the wavelength range between 380 and 800 nm. Under daylight conditions, the average normal sighted human eye is most sensitive at a wavelength of 555 nm, resulting in the fact that green light at this wavelength produces the impression of highest “brightness” when compared to light at other wavelengths. The spectral sensitivity function of the average human eye under daylight conditions (photopic vision) is defined by the CIE spectral luminous efficiency function V(λ). Only in very rare cases, the spectral sensitivity of the human eye under dark adapted conditions (scotopic vision), defined by the spectral luminous efficiency function V’(ë), becomes technically relevant. By convention, these sensitivity functions are normalized to a value of 1 in their maximum.
As an example, the photopic sensitivity of the human eye to monochromatic light at 490 nm amounts to 20% of its sensitivity at 555 nm. As a consequence, when a source of monochromatic light at 490 nm emits five times as much power (expressed in watts) than an otherwise identical source of monochromatic light at 555 nm, both sources produce the impression of same “brightness” to the human eye.
Fig. II.13. Spectral luminous efficiency functions V(λ) for photopic vision and V’(λ) for scotopic vision, as defined by the CIE. |
Glue ear is a condition where the middle ear fills with glue-like fluid instead of air. This causes dulled hearing. It clears by itself in most cases. An operation to clear the fluid and to insert ventilation tubes (grommets) may be advised if glue ear persists. This leaflet is about the operations used to treat glue ear. Please note: most children with glue ear do not need an operation.
This leaflet is part of our series on ear infection
Who needs an operation for glue ear?
An operation may be advised to restore hearing to normal if glue ear does not clear after a time of 'watchful waiting', typically three months.
What are the operations?
- Myringotomy and grommet insertion is the common operation. (See diagram below.) Myringotomy is a tiny cut (about 2-3 mm) made in the eardrum. The fluid is drained and a ventilation tube (grommet) is often inserted. A grommet is like a tiny pipe that is put across the eardrum. The grommet lets air to get into the middle ear. Hearing improves immediately.
- Removal of the adenoids is sometimes advised. Adenoids are small clumps of glandular tissue (similar to tonsils). They are attached at the back of the nose cavity near to the opening of the Eustachian tube. If the adenoids are large then taking them out may improve the drainage of the Eustachian tube. Adenoids tend to be removed only if the child with glue ear also has persistent or recurring colds or other respiratory infections.
- A laser method to make a tiny hole in the eardrum and allow drainage has been developed. This has a similar effect to myringotomy and grommet insertion. Studies show that it is, on average, not as successful as grommet insertion. However, the procedure does not require a general anaesthetic. So, it may have a place in selected cases. Also, a laser rather than a fine knife is sometimes used to create the hole in the eardrum in which to place a grommet.
These operations above only take a short time to do. They are often done as a 'day case'. Sometimes an overnight stay in hospital is needed.
Are there any risks with these operations?
As with any operation, there is a risk of complications from the surgery and with the anaesthetic. However, the risk is very small.
Some common concerns after grommets are put in
- Swimming is usually fine. However, it is best to avoid underwater swimming or ducking the head deeply into water. There is no evidence to suggest that ear plugs or swimming hats need to be worn.
- Washing. Try not to get soapy water into the ears. Don't duck the head into soapy water. Wash the outside of the ears in the normal way. A cotton wool ball with Vaseline® placed in the ear canal could be used to prevent water from getting into the ear.
- Flying in a plane is actually easier if you have a ventilation tube (grommet) in your ear. The grommet allows the pressure of air to equalise between the middle and outer ear. This prevents ear pain during landing and take-off.
The diagram below shows where a grommet is placed:
What happens to the grommet after it is put in the ear?
Ventilation tubes (grommets) allow air into the middle ear. Grommets normally fall out of the ear as the eardrum grows, usually after 4-12 months. By this time the glue ear has often gone away. The cut in the eardrum made for the grommet normally heals quickly when the grommet falls out.
Grommets are so small that you may not notice when they fall out of the ear.
Do grommets cure the glue ear for good?
When the ventilation tube (grommet) falls out the problem with glue ear is usually gone. However, sometimes the fluid returns after the grommet falls out and the eardrum heals over. A repeat operation to put a new grommet in is sometimes needed. In some children a grommet is needed several times until glue ear clears for good.
Are there any complications with grommets?
- An ear discharge develops at some point in about 1 in 20 children with ventilation tubes (grommets). This is often during or after a cold. This is not usually serious or painful. See your GP about this if it occurs. Antibiotic medicine or ear drops may be prescribed and the discharge usually soon clears. Occasionally, the discharge continues (persists) and the grommet needs to be taken out.
- Minor damage and scarring to the eardrum may occur but this is unlikely to cause any problems.
- Rarely, a small hole (perforation) persists in the eardrum after the grommet has come out. A small operation can fix this should it occur.
Dr Tim Kenny
Dr Laurence Knott
Dr Helen Huins |
|—n , pl -gies|
|1.||intensity or vitality of action or expression; forcefulness|
|2.||capacity or tendency for intense activity; vigour|
|3.||vigorous or intense action; exertion|
|a. the capacity of a body or system to do work|
|b. E a measure of this capacity, expressed as the work that it does in changing to some specified reference state. It is measured in joules (SI units)|
|5.||kinetic energy See also potential energy a source of power|
|[C16: from Late Latin energīa, from Greek energeia activity, from energos effective, from |
energy en·er·gy (ěn'ər-jē)
The capacity for work or vigorous activity; vigor; power.
The capacity of a physical system to do work.
energy [%PREMIUM_LINK%] (ěn'ər-jē) Pronunciation Key |
The capacity or power to do work, such as the capacity to move an object (of a given mass) by the application of force. Energy can exist in a variety of forms, such as electrical, mechanical, chemical, thermal, or nuclear, and can be transformed from one form to another. It is measured by the amount of work done, usually in joules or watts. See also conservation of energy, kinetic energy, potential energy. Compare power, work.
Note: The most important property of energy is that it is conserved — that is, the total energy of an isolated system does not change with time. This is known as the law of conservation of energy. Energy can, however, change form; for example, it can be turned into mass and back again into energy. |
An inter-active activity to demonstrate cooperation and acceptance of difference. This is often the hidden aim. The introduction can state this or it can be billed as a warm-up activity or one on a completely different topic.
Ask people to form groups of three or four. Then ask them to demonstrate, by forming a human sculpture, something on the topic you give them. The topic can be:
• the benefit of cooperation
• accepting the difference of others
• how this group or class works
• nightlife in the area
(Clearly almost any topic can be chosen, depending on the group, situation and your aim).
The group are told they cannot talk at all during the exercise. They are given a set amount of time and told they will then present their sculpture to all the other groups. Only after this will talking be allowed.
One person in each group is given a ‚disability‘ by the leader. They must keep their hand behind their back or in their pocket. Alternatively they must stand on one leg or stay bent over. Other variations are possible. No reasons are given for this, however they must stay this way until the end of the presentations.
After each group has made their presentation, allow each group some time to talk about what they achieved, how they felt about it and what, if anything, they learnt from it.
Open this out to a general discussion. Some specific questions should also be posed:
- What did it feel like working without words?
- How well did the group work together?
- What helped or hindered this working together?
- How did the individual wish the imposed ‚disability‘ feel?
- How did the group react to this person and how did they feel about them?
- What did you learn about: human sculptures; the topic you were asked to sculpt; cooperation; difference?
(Many other questions could be posed depending on the group, the time and the nature of your work. For larger groups, or even for smaller ones, these questions could be raised with small groups first before the large group discussion).
Some difficult issues could arise during this exercise and time will need to be allowed to look at them properly. The leader will probably need to make choices about which questions to focus on. |
Black Codes (United States)
|Part of a series of articles on |
The Black Codes were laws passed by Southern states in 1865 and 1866 in the United States after the American Civil War with the intent and the effect of restricting African Americans' freedom, and of compelling them to work in a labor economy based on low wages or debt. Black Codes were part of a larger pattern of Southern whites, who were trying to suppress the new freedom of emancipated African-American slaves, the freedmen. Black codes were essentially replacements for slave codes in those states. Before the war in states that prohibited slavery, some Black Codes were also enacted. Northern states such as Ohio, Illinois, Indiana, Michigan, and New York enacted Black Codes to discourage free blacks from residing in those states and denying them equal rights, including the right to vote, the right to public education, and the right to equal treatment under the law. Some of these northern black codes were repealed around the same time that the civil war ended and slavery was abolished.
Since the colonial period, colonies and states had passed laws that discriminated against free Blacks. In the South, these were generally included in "slave codes"; the goal was to reduce influence of free blacks (particularly after slave rebellions) because of their potential influence on slaves. Restrictions included prohibiting them from voting (although North Carolina allowed this before 1831), bearing arms, gathering in groups for worship and learning to read and write. A major purpose of these laws was to preserve slavery among other things.
In the first two years after the Civil War, white-dominated southern legislatures passed Black Codes modeled after the earlier slave codes. They were particularly concerned with controlling movement and labor, as slavery had given way to a free labor system. Although freedmen had been emancipated, their lives were greatly restricted by the Black Codes.
The term Black Codes was given by "negro leaders and the Republican organs", according to historian John S. Reynolds. The defining feature of the Black Codes was broad vagrancy law, which allowed local authorities to arrest freedpeople for minor infractions and commit them to involuntary labor. This period was the start of the convict lease system, also described as "slavery by another name" by Douglas Blackmon in his 2008 book on this topic.
- 1 Background
- 2 Postwar years
- 3 Legislation in Southern states
- 4 Reconstruction and Jim Crow
- 5 Legacy and interventions
- 6 Comparative history
- 7 See also
- 8 Notes
- 9 External links
Vagrancy laws date back to the end of feudalism in Europe. Introduced by aristocratic and landowning classes, they had the dual purpose of restricting access of "undesirable" classes to public spaces and of ensuring a labor pool. Serfs were not emancipated from their land.
Over the period of 1687–1865, Virginia enacted more than 130 slave statutes, among which were seven major slave codes, with some containing more than fifty provisions. "Black codes" in the antebellum South contained more regulations of free Blacks than of slaves. Chattel slaves basically lived under the complete control of their owners; free blacks presented a challenge to the boundaries of White-dominated society.
Black Codes in the antebellum South heavily regulated the activities and behavior of blacks. North Carolina restricted slaves from leaving their plantation; if one tried to court (date) a woman on another property, he risked severe punishments at the hands of the patrollers or needed a pass in order to pursue this relationship. In many southern states, particularly after the insurrection of 1831, free Blacks were prohibited from the basic constitutional rights to assemble in groups, bear arms, learn to read and write, exercise free speech, or testify against white people in Court. After 1810, states made manumissions of slaves more difficult to obtain, often requiring an act of legislature for each case. This sharply reduced the incidence of planters freeing slaves.
There were some protections of slaves, such as a prohibition against masters murdering slaves. After the Louisiana Purchase, the state of Louisiana based its state laws on the French colonial Code Noir issued in 1685. New restrictions, as well, were placed on intermarriage, concubinage and miscegenation with slaves. Free whites could no longer marry a slave and thereby emancipate her and her children, and no freed person was capable of receiving a donation from a white person, whether by act inter vivos or mortis causa.
As the abolitionist movement gained force and refugee slaves escaping through the Underground Railroad increased, concern about blacks heightened among some whites in the North. Territories and states near the slave states did not welcome free blacks to settle with them. But north of the Mason–Dixon line, anti-Black laws were generally less severe. Some public spaces were segregated, and Blacks generally did not have the right to vote. In Oregon, Blacks were forbidden to settle, marry or sign contracts.
All the slave states passed anti-miscegenation laws banning the marriage of white and black people, as did several new free states of the former Northwest Territory, including Indiana, Illinois and Michigan. Indiana and Illinois shared borders with slave states across the Ohio and Mississippi rivers. The southern populations of these states had generally migrated from the Upper South and shared cultures more akin to those of the South across the Ohio River than with the northern populations, who had migrated from New England and New York and were part of Yankee culture. In some states these codes included vagrancy laws that targeted unemployed blacks, apprentice laws that made black orphans and dependents available for hire to whites, and commercial laws that excluded blacks from certain trades and businesses and restricted their ownership of property.
Article 13 of Indiana's 1851 Constitution stated "No Negro or Mulatto shall come into, or settle in, the State, after the adoption of this Constitution." The 1848 Constitution of Illinois contributed to the state legislature passing one of the harshest Black Code systems in the nation until the Civil War. The Illinois Black Code of 1853 prohibited any Black persons from outside of the state from staying in the state for more than ten days, subjecting Blacks who violated that rule to arrest, detention, a $50 fine, or deportation.
Maryland passed vagrancy and apprentice laws, and required Blacks to obtain licenses from Whites before doing business. It prohibited immigration of free Blacks until 1865. Most of the Maryland Black Code was repealed in the Constitution of 1867. Black women were not allowed to testify against White men with whom they had children, giving them a status similar to wives.
The Union Army relied on the labor of newly freed people, and did not always treat them fairly. Thomas W. Knox wrote: "The difference between working for nothing as a slave, and working for the same wages under the Yankees, was not always perceptible." At the same time, military officials resisted local attempts to apply pre-war laws to the freed people. After the Emancipation Proclamation, the Army conscripted Black "vagrants" and sometimes others.
The Union Army applied the northern wage system of free labor to freedmen after the Emancipation Proclamation; they effectively upgraded free Blacks from "contraband" status. General Nathaniel P. Banks in Louisiana initiated a system of wage labor in February 1863 in Louisiana; General Lorenzo Thomas implemented a similar system in Mississippi. The Banks-Thomas system offered Blacks $10 a month, with the Army's commitment to provide rations, clothing, and medicine. The worker would have to agree to an unbreakable one-year contract. In 1864, Thomas expanded the system to Tennessee, and allowed white landowners near the Nashville contraband camp to rent the labor of refugees.
Against opposition from elements of the Republican Party, Abraham Lincoln accepted this system as a step on the path to gradual emancipation. Abolitionists continued to criticize the labor system. Wendell Phillips said that Lincoln's proclamation had "free[d] the slave, but ignore[d] the Negro", calling the Banks-Thomas year-long contracts tantamount to serfdom. The Worcester Spy described the government's answer to slavery as "something worse than failure."
|Wikisource has original text related to this article:|
As the war ended, the US Army implemented Black Codes to regulate the behavior of black people in general society. Although the Freedmen's Bureau had a mandate to protect blacks from a hostile Southern environment, it also sought to keep blacks in their place as laborers in order to allow production on the plantations to resume so that the South could revive its economy. The Freedmen's Bureau cooperated with Southern authorities in rounding up black "vagrants" and placing them in contract work. In some places, it supported owners to maintain control of young slaves as apprentices.
After the war
Soon after the end of slavery, white planters encountered a labor shortage and sought a way to manage it. Although blacks did not all abruptly stop working, they did try to work less. In particular, many sought to reduce their Saturday work hours, and women wanted to spend more time on child care. In the view of one contemporary economist, freed people exhibited this "noncapitalist behavior" because the condition of being owned had "shielded the slaves from the market economy" and they were therefore unable to perform "careful calculation of economic opportunities".
An alternative explanation treats the labor slowdown as a form of gaining leverage through collective action. Another possibility is that freed blacks assigned value to leisure and family time in excess of the monetary value of additional paid labor. Indeed, freedpeople certainly did not want to work the long hours that had been forced upon them for their whole lives. Whatever its causes, the sudden reduction of available labor posed a challenge to the Southern economy, which had relied upon intense physical labor to profitably harvest cash crops, particularly King Cotton.
Preexisting White American belief of Black inferiority informed post-war attitudes and white racial dominance continued to be culturally embedded; whites believed both that Black people were destined for servitude and that they would not work unless physically compelled. For their part, free Blacks no longer felt compelled to show conspicuous deference to White people. The enslaved also strove to create a semi-autonomous social world, removed from the plantation and the gaze of the slave owner. The racial divisions which slavery had created immediately became more obvious. Blacks also bore the brunt of Southern anger over defeat in the War.
Legislation on the status of freedpeople was often mandated by constitutional conventions held in 1865. Mississippi, South Carolina, and Georgia all included language in their new state constitutions which instructed the legislature to "guard them and the State against any evils that may arise from their sudden emancipation". The Florida convention of October 1865 included a vagrancy ordinance that was in effect until process Black Codes could be passed through the regular legislative process.
Legislation in Southern states
Black Codes restricted black people's right to own property, conduct business, buy and lease land, and move freely through public spaces. A central element of the Black Codes were vagrancy laws. States criminalized men who were out of work, or who were not working at a job whites recognized. Failure to pay a certain tax, or to comply with other laws, could also be construed as vagrancy.
Nine southern states updated their vagrancy laws in 1865–1866. Of these, eight allowed convict leasing (a system in which state prison hired out convicts for labor) and five allowed prisoner labor for public works projects. This created a system that established incentives to arrest black men, as convicts were supplied to local governments and planters as workers. The planters or other supervisors were responsible for their board and food, and black convicts were kept in miserable conditions. As Douglas Blackmon wrote, it was "slavery by another name". Because of their reliance on convict leasing, Southern states did not build any prisons until the late 19th century.
Strict punishments against theft also served to ensnare many people in the legal system. Previously, Blacks had been part of the domestic economy on a plantation, and were more or less able to use supplies that were available. After emancipation, the same act performed by someone working the same land might be labeled as theft, leading to arrest and involuntary labor.
Some states explicitly curtailed Black people's right to bear arms, justifying these laws with claims of imminent insurrection. In Mississippi and Alabama, these laws were enforced through the creation of special militias.
Historian Samuel McCall, who published a biography about abolitionist Thaddeus Stevens, commented in 1899 that the Black Codes had "established a condition but little better than that of slavery, and in one important respect far worse": by severing the property relationship, they had diminished the incentive for property owners to ensure the relative health and survival of their workers.
Regarding the question of whether Southern legislatures deliberately tried to maintain White supremacy, Beverly Forehand writes: "This decision was not a conscious one on the part of white legislators. It was simply an accepted conclusion."
During Reconstruction, state legislatures passed some laws that established some positive rights for freedmen. States legalized Black marriages and in some cases increased the rights of freedmen to own property and conduct commerce.
Mississippi was the first state to pass Black Codes. Its laws served as a model for those passed by other states, beginning with South Carolina, Alabama, and Louisiana in 1865, and continuing with Florida, Virginia, Georgia, North Carolina, Texas, Tennessee, and Arkansas at the beginning of 1866. Intense Northern reaction against the Mississippi and South Carolina laws led some of the states that subsequently passed laws to excise overt racial discrimination; but, their laws on vagrancy, apprenticeship, and other topics were crafted to effect a similarly racist regime. Even states that carefully eliminated most of the overt discrimination in their Black Codes retained laws authorizing harsher sentences for Black people.
Mississippi was the first state to legislate a new Black Code after the war, beginning with "An Act to confer Civil Rights on Freedmen". This law allowed Blacks to rent land only within cities—effectively preventing them from earning money through independent farming. It required Blacks to present, each January, written proof of employment. The law defined violation of this requirement as vagrancy, punishable by arrest—for which the arresting officer would be paid $5, to be taken from the arrestee's wages. Provisions akin to fugitive slave laws mandated the return of runaway workers, who would lose their wages for the year. An amended version of the vagrancy law included punishments for sympathetic whites:
That all freedmen, free negroes and mulattoes in this State, over the age of eighteen years, found on the second Monday in January, 1866, or thereafter, without lawful employment or business, or found unlawfully assembling themselves together, either in the day or night time, and all white persons so assembling themselves with freedmen, free negroes or mulattoes, or usually associating with freedmen, free negroes or mulattoes, on terms of equality, or living in adultery or fornication with a freed woman, free negro or mulatto, shall be deemed vagrants, and on conviction thereof shall be fined in a sum not exceeding, in the case of a freedman, free negro, or mulatto, fifty dollars, and a white man two hundred dollars, and imprisoned, at the discretion of the court, the free negro not exceeding ten days, and the white man not exceeding six months.
Whites could avoid the code's penalty by swearing a pauper's oath. In the case of blacks, however: "the duty of the sheriff of the proper county to hire out said freedman, free negro or mulatto, to any person who will, for the shortest period of service, pay said fine or forfeiture and all costs." The laws also levied a special tax on blacks (between ages 18 and 60); those who did not pay could be arrested for vagrancy.
Another law allowed the state to take custody of children whose parents could or would not support them; these children would then be "apprenticed" to their former owners. Masters could discipline these apprentices with corporal punishment. They could re-capture apprentices who escaped and threaten them with prison if they resisted.
Mississippi rejected the Thirteenth Amendment on December 5.
The next state to pass Black Codes was South Carolina, which had on November 13 ratified the Thirteenth Amendment—with a qualification that Congress did not have the authority to regulate the legal status of freedmen. Newly elected governor James Lawrence Orr said that blacks must be "restrained from theft, idleness, vagrancy and crime, and taught the absolute necessity of strictly complying with their contracts for labor".
South Carolina's new law on "Domestic Relations of Persons of Color" established wide-ranging rules on vagrancy resembling Mississippi's. Conviction for vagrancy allowed the state to "hire out" blacks for no pay. The law also called for a special tax on blacks (all males and unmarried females), with non-paying blacks again guilty of vagrancy. The law enabled forcible apprenticeship of children of impoverished parents, or of parents who did not convey "habits of industry and honesty". The law did not include the same punishments for Whites in dealing with fugitives.
The South Carolina law created separate courts for Black people, and authorized capital punishment for crimes including theft of cotton. It created a system of licensing and written authorizations that made it difficult for Blacks to engage in normal commerce.
The South Carolina Code clearly borrowed terms and concepts from the old slave codes, re-instituting a rating system of "full" or "fractional" farmhands and often referring to bosses as "masters".
A "Colored People's Convention" assembled at Zion Church in Charleston, South Carolina, to condemn the Codes. In a memorial (petition) to Congress, the Convention expressed gratitude for emancipation and establishment of the Freedmen's Bureau, but requested (in addition to suffrage) "that the strong arm of law and order be placed alike over the entire people of this State; that life and property be secured, and the laborer as free to sell his labor as the merchant his goods."
Some Whites, meanwhile, thought the new laws did not go far enough. One planter suggested that the new laws would require paramilitary enforcement: "As for making the negroes work under the present state of affairs it seems to me a waste of time and energy ... We must have mounted Infantry that the freedmen know distinctly that they succeed the Yankees to enforce whatever regulations we can make." Edmund Rhett (son of Robert Rhett) wrote that although South Carolina might be unable to undo abolition,
it should to the utmost extent practicable be limited, controlled, and surrounded with such safe guards, as will make the change as slight as possible both to the white man and to the negro, the planter and the workman, the capitalist and the laborer.
However, even as the legislators passed these laws, they despaired of the forthcoming response from Washington. James Hemphill said: "It will be hard to persuade the freedom shriekers that the American citizens of African descent are obtaining their rights." Orr moved to block further laws containing explicit racial discrimination. In 1866, the South Carolina code came under increasing scrutiny in the Northern press and was compared unfavorably to freedmen's laws passed in neighboring Georgia, North Carolina, and Virginia.
The Louisiana legislature, seeking to ensure that freedmen were "available to the agricultural interests of the state", passed similar yearly contract laws and expanded its vagrancy laws. Its vagrancy laws did not specify Black culprits, though they did provide a "good behavior" loophole subject to plausibly racist interpretation. Louisiana passed harsher fugitive worker laws and required blacks to present dismissal paperwork to new employers.
State legislation was amplified by local authorities, who ran less risk of backlash from the federal government. Opelousas, Louisiana, passed a notorious code which required freedpeople to have written authorization to enter the town. The code prevented freedpeople from living in the town or walking at night except under supervision of a White resident.
Some of the leading officers of the state down there—men who do much to form and control the opinions of the masses—instead of doing as they promised, and quietly submitting to the authority of the government, engaged in issuing slave codes and in promulgating them to their subordinates, ordering them to carry them into execution, and this to the knowledge of state officials of a higher character, the governor and others. ... These codes were simply the old black code of the state, with the word 'slave' expunged, and 'Negro' substituted. The most odious features of slavery were preserved in them.
Conway describes surveying the Louisiana jails and finding large numbers of Black men who had been secretly incarcerated. These included members of the Seventy-Fourth Colored Infantry who had been arrested the day after they were discharged.
The state passed a harsher version of its code in 1866, criminalizing "impudence", "swearing", and other signs of "disobedience" as determined by whites.
Of the Black Codes passed in 1866 (after the Northern reaction had become apparent), only Florida's rivaled those of Mississippi and South Carolina in severity. Florida's slaveowners seemed to hold out hope that the institution of slavery would simply be restored. Advised by the Florida governor and attorney general as well as by the Freedmen's Bureau that it could not constitutionally revoke Black people's right to bear arms, the Florida legislature refused to repeal this part of the codes.
These laws applied to any "person of color", which was defined as someone with at least one Negro great-grandparent, or one-eighth black ancestry. White women could not live with men of color. Colored workers could be punished for disrespecting White employers. The explicit racism in the law was supplemented by racist enforcement discretion (and other inequalities) in the practice of law enforcement and legal systems.
In Maryland, a fierce battle began immediately after emancipation (by the Maryland Constitution of 1864) over requiring apprenticeship of young black people. By 1860, 45.6% of the black population in the state was already free. Former slave owners rushed to place the children of freedpeople in multi-year apprenticeships; the Freedmen's Bureau and some others tried to stop them. The legislature stripped Baltimore Judge Hugh Lennox Bond of his position because he cooperated with the Bureau in this matter. Salmon Chase, as Chief Justice of the United States Supreme Court, eventually overruled the Maryland apprentice laws on the grounds of their violation of the Civil Rights Act of 1866.
North Carolina's Black Code specified racial differences in punishment, establishing harsher sentences for Blacks convicted of rape.
The Texas Constitutional Convention met in February 1866, declined to ratify the (already effective) Thirteenth Amendment, provided that Blacks would be "protected in their rights of person and property by appropriate legislation" and guaranteed some degree of rights to testify in court. Texas modeled its laws on South Carolina's.
The legislature defined Negroes as people with at least one African great-grandparent. Negroes could choose their employer, before a deadline. After they had made a contract, they were bound to it. If they quit "without cause of permission" they would lose all of their wages. Workers could be fined $1 for acts of disobedience or negligence, and 25 cents per hour for missed work. The legislature also created a system of apprenticeship (with corporal punishment) and vagrancy laws. Convict labor could be hired out or used in public works.
Negroes were not allowed to vote, hold office, sit on juries, serve in local militia, carry guns on plantations, homestead, or attend public schools. Interracial marriage was banned. Rape sentencing laws stipulated either capital punishment, or life in prison, or a minimum sentence of five years. Even to commentators who favored the codes, this "wide latitude in punishment" seemed to imply a clear "anti-Negro bias".
Tennessee had been occupied by the Union for a long period during the war. As military governor of Tennessee, Andrew Johnson declared a suspension of the slave code in September 1864. However, these laws were still enforced in lower courts. In 1865, Tennessee freedpeople had no legal status whatsoever, and local jurisdictions often filled the void with extremely harsh Black Codes. During that year, Blacks went from one-fiftieth to one-third of the State's prison population.
Tennessee had a particularly urgent desire to re-enter the Union's good graces and end the occupation. When the Tennessee Legislature began to debate a Black Code, it received such negative attention in the Northern press that no comprehensive Code was ever established. Instead, the State legalized Black suffrage and passed a civil rights law guaranteeing Blacks equal rights in commerce and access to the Courts.
However, Tennessee society, including its judicial system, retained the same racist attitudes as did other states. Although its legal code did not discriminate against Blacks so explicitly, its law enforcement and criminal justice systems relied more heavily on racist enforcement discretion to create a de facto Black Code. The state already had vagrancy and apprenticeship laws which could easily be enforced in the same way as Black Codes in other states. Vagrancy laws came into much more frequent use after the war. And just as in Mississippi, Black children were often bound in apprenticeship to their former owners.
The legislature passed two laws on May 17, 1865; one to "Punish all Armed Prowlers, Guerilla, Brigands, and Highway Robbers"; the other to authorize capital punishment for thefts, burglary, and arson. These laws were targeted at Blacks and enforced disproportionately against Blacks, but did not discuss race explicitly.
Tennessee law permitted Blacks to testify against Whites in 1865, but this change did not immediately take practical effect in the lower courts. Blacks could not sit on juries. Still on the books were laws specifying capital punishment for a Black man who raped a White woman.
Kentucky had established a system of leasing prison labor in 1825. This system drew a steady supply of laborers from the decisions of "negro courts", informal tribunals which included slaveowners. Free Blacks were frequently arrested and forced into labor.
Kentucky did not secede from the Union and therefore gained wide leeway from the federal government during Reconstruction. With Delaware, Kentucky did not ratify the Thirteenth Amendment and maintained legal slavery until it was nationally prohibited when the Amendment went into effect in December 1865. After the Thirteenth Amendment took effect, the state was obligated to rewrite its laws.
The result was a set of Black Codes passed in early 1866. These granted a set of rights: to own property, make contracts, and some other innovations. They also included new vagrancy and apprentice laws, which did not mention Blacks explicitly but were clearly directed toward them. The vagrancy law covered loitering, "rambling without a job" and "keeping a disorderly house". City jails filled up; wages dropped below pre-war rates.
The Freedmen's Bureau in Kentucky was especially weak and could not mount a significant response. The Bureau attempted to cancel a racially discriminatory apprenticeship law (which stipulated that only White children learn to read) but found itself thwarted by local authorities.
Some legislation also created informal, de facto discrimination against Blacks. A new law against hunting on Sundays, for example, prevented Black workers from hunting on their only day off.
Kentucky law prevented Blacks from testifying against Whites, a restriction which the federal government sought to remedy by providing access to federal courts through the Civil Rights Act of 1866. Kentucky challenged the constitutionality of these courts and prevailed in Blyew v. United States (1872). All contracts required the presence of a White witness. Passage of the Fourteenth Amendment did not have a great effect on Kentucky's Black Codes.
Reconstruction and Jim Crow
The Black Codes outraged public opinion in the North because it seemed the South was creating a form of quasi-slavery to negate the results of the war. When the Radical 39th Congress re-convened in December 1865, it was generally furious about the developments that had transpired during Johnson's Presidential Reconstruction. The Black Codes, along with the appointment of prominent Confederates to Congress, signified that the South had been emboldened by Johnson and intended to maintain its old political order. Railing against the Black Codes as returns to slavery in violation of the Thirteenth Amendment, Congress passed the Civil Rights Act of 1866, the Fourteenth Amendment, and the Second Freedmen's Bureau Bill.
After winning large majorities in the 1866 elections, the Republican Congress passed the Reconstruction Acts placing the South under military rule. This arrangement lasted until the military withdrawal arranged by the Compromise of 1877. In some historical periodizations, 1877 marks the beginning of the Jim Crow era.[a]
The 1865–1866 Black Codes were an overt manifestation of the system of white supremacy that continued to dominate the American South. Historians have described this system as the emergent result of a wide variety of laws and practices, conducted on all levels of jurisdiction. Because legal enforcement depended on so many different local codes, which underwent less scrutiny than statewide legislation, historians still lack a complete understanding of their full scope. It is clear, however, that even under military rule, local jurisdictions were able to continue a racist pattern of law enforcement, as long as it took place under a legal regime that was superficially race-neutral.
In 1893–1909 every Southern state except Tennessee passed new vagrancy laws. These laws were more severe than those passed in 1865, and used vague terms that granted wide powers to police officers enforcing the law. In wartime, Blacks might be disproportionately subjected to "work or fight" laws, which increased vagrancy penalties for those not in the military. The Supreme Court upheld racially discriminatory state laws and invalidated federal efforts to counteract them; in Plessy v. Ferguson (1896) it upheld the constitutionality of racial segregation and introduced the "separate but equal" doctrine.
A general system of legitimized anti-Black violence, as exemplified by the Ku Klux Klan, played a major part in enforcing the practical law of white supremacy. The constant threat of violence against Black people (and White people who sympathized with them) maintained a system of extralegal terror. Although this system is now well known for prohibiting Black suffrage after the Fifteenth Amendment, it also served to enforce coercive labor relations. Fear of random violence provided new support for a paternalistic relationship between plantation owners and their Black workers.
Legacy and interventions
This regime of White-dominated labor was not identified by the North as involuntary servitude until after 1900. In 1907, Attorney General Charles Joseph Bonaparte issued a report, Peonage Matters, which found that, beyond debt peonage, there was a widespread system of laws "considered to have been passed to force negro laborers to work".
After creating the Civil Rights Section in 1939, the federal Department of Justice launched a wave of successful Thirteenth Amendment prosecutions against involuntary servitude in the South.
Many of the Southern vagrancy laws remained on the books until the Supreme Court's Papachristou v. Jacksonville decision in 1972. Although by 1972 the laws were defended as preventing crime, the Court held that Jacksonville's vagrancy law "furnishes a convenient tool for 'harsh and discriminatory enforcement by local prosecuting officials, against particular groups deemed to merit their displeasure.'"
Even after Papachristou, police activity in many parts of the United States discriminates against racial minority groups. Gary Stewart has identified contemporary gang injunctions—which target young Black or Latino men who gather in public—as a conspicuous legacy of Southern Black Codes. Stewart argues that these laws maintain a system of white supremacy and reflect a system of racist prejudice, even though racism is rarely acknowledged explicitly in their creation and enforcement. Contemporary Black commentators have argued that the current disproportionate incarceration of African Americans, with a concomitant rise in prison labor, is comparable (perhaps unfavorably) with the historical Black Codes.
The desire to recuperate the labor of officially emancipated people is common among societies (most notably in Latin America) that were built on slave labor. Vagrancy laws and peonage systems are widespread features of post-slavery societies. One theory suggests that particularly restrictive laws emerge in larger countries (compare Jamaica with the United States) where the ruling group does not occupy land at a high enough density to prevent the freed people from gaining their own. However, it seems, the United States was uniquely successful in maintaining involuntary servitude after legal emancipation.
Historians have also compared the end of the slavery in the United States to the formal decolonization of Asian and African nations. Like emancipation, decolonization was a landmark political change—but its significance, according to some historians, was tempered by the continuity of economic exploitation. The end of legal slavery in the United States did not seem to have major effects on the global economy or international relations. Given the pattern of economic continuity, writes economist Pieter Emmer, "the words emancipation and abolition must be regarded with the utmost suspicion."
- 40 acres and a mule
- Apartheid in South Africa
- Code Noir
- Grandfather clause
- Judicial aspects of race in the United States
- List of Jim Crow law examples by state
- Oregon black exclusion laws
- Racial segregation in the United States
- Republic of New Afrika
- Reverse Underground Railroad
- Wage slavery
- History of unfree labor in the United States
- Link text
- James Calvin Hemphill, "John Schreiner Reynolds", Men of Mark in South Carolina: Ideals of American Life Vol. II; Washington, D.C.: Men of Mark Publishing Co., 1908.
- Kermit L. Hall, "Political Power and Constitutional Legitimacy: The South Carolina Ku Klux Klan Trials" Archived 2013-03-16 at the Wayback Machine.; Emory Law Journal 33, Fall 1984.
- John S. Reynolds, Reconstruction in South Carolina; Columbia, SC: State Co., 1905; p. 27.
- Douglas Blackmon, Slavery by Another Name: The Re-Enslavement of Black Americans from the Civil War to World War II, New York: Doubleday, 2008
- Stewart, White Codes and Broken Femurs (1998), pp. 2257–2258.
- Palmer, Vernon Valentine (April 2006). "The Customs of Slavery: The War Without Arms". American Journal of Legal History. 2 (48): 177.
- Forehand, "Striking Resemblance" (1996), p. 6.
- Griffin, Rebecca J (April 2004). ""Goin' Back Over There to See That Girl": Competing Social Spaces in the Lives of the Enslaved in Antebellum North Carolina". Slavery & Abolition. 25 (1): 108.
- Forte, "Spiritual Equality" (1998), p. 579–580.
- Painter, Creating Black Americans (2005), pp. 79–81.
- Forehand, "Striking Resemblance" (1996), p. 7.
- Ranney, In the Wake of Slavery (2006), p. 15. "All Southern states imposed at least minimal limits on slave punishment, for example, by making murder or life-threatening injury of slaves a crime, and a few states allowed slaves a limited right of self-defense."
- Palmer, Vernon Valentine (April 2006). "The Customs of Slavery: The War Without Arms". American Journal of Legal History. 2 (48): 185.
- Mcclintock, Thomas C. (1995). "James Saules, Peter Burnett, and the Oregon Black Exclusion Law of June 1844". The Pacific Northwest Quarterly. 86 (3): 121–130. doi:10.2307/40491550. JSTOR 40491550.
- "The Legal Map of Interracial Relations 1662–1967". Retrieved 2010-01-19.
- "black codes". www.reference.com. Retrieved 2014-12-02.
- Bridges, Roger D. The Illinois Black Codes. http://www.lib.niu.edu/1996/iht329602.html
- Ranney, In the Wake of Slavery (2006), p. 17. "Between 1795 and 1810, Maryland enacted vagrancy laws similar to Delaware's; required free blacks to obtain certificates of good character from local officials in order to sell products or keep hunting equipment; and allowed its courts to apprentice children of destitute or unfit black parents to white masters."
- DuBois, Black Reconstruction (1935), p. 564.
- Forehand, Striking Resemblance (1996), p. Abstract.
- DuBois, Black Reconstruction (1935), p. 178.
- Thomas W. Knox, Camp-Fire and Cotton-Field: Southern Adventure in Time of War: Life with the Union Armies, and Residence on a Louisiana Plantation, New York: Blelock & Co., 1865; p. 317. Quoted in Daniel, "Metamorphosis of Slavery" (1979), pp. 89–90.
- Forehand, "Striking Resemblance" (1996), pp. 20–24.
- Forehand, "Striking Resemblance" (1996), p. 25.
- WPA documents reproduced at North Carolina Slave Narratives; quoted in Forehand, "Striking Resemblance" (1996), p. 120.
- Forte, "Spiritual Equality" (1998), pp. 589–590. Quote: "Much more troublesome was the Union's treatment of the freed slaves in Louisiana and the South as a whole. The Union military authorities in the South approved a plan of apprenticeship for the freed black, a policy that Lincoln seemed to accept, at least as an interim measure 'conforming substantially to the most approved plans of gradual emancipation'."
- Belz, A New Birth of Freedom (2000), pp. 45–46.
- Forehand, "Striking Resemblance" (1996), pp. 28–29.
- Belz, A New Birth of Freedom (2000), pp. 52–53.
- Wilson, Black Codes (1965), p. 57. "In a nutshell, the sum of army and Freedmen's Bureau policies was: protect the negroes from violence and actual enslavement, but keep as many as possible on the plantations and compel them to work. Both agencies preserved 'white man's rule,' and though both of them did, as George Bently said of the Freedmen's Bureau, 'maintain a fairly strong guard against any form of reenslavement of the Negroes', their interest in the welfare and happiness of the freedmen did not, as a whole, extend far beyond that safeguard in 1865 and 1866. It is also as true of one as of the other that its policies, in the main, were 'those that planters and other businessmen desired.'"
- Wilson, Black Codes (1965), p. 58–59.
- Daniel, Metamorphosis of Slavery (1979), p. 96. "The yearly contract was one of the most important elements in the landlord's control over labor—not what the contract stated explicitly, but what it implied and how it was executed. The pattern emerged immediately after the war. With encouragement from the Freedmen's Bureau, blacks signed up for a year's work, and the vigilant eyes of federal officials noted that many contracts resembled slavery."
- Wormser, The Rise and Fall of Jim Crow (2003), p. 11.
- Richardson, Florida Black Codes (1969), p. 370.
- Wilson, Black Codes (1965), pp. 54–55. "The larger problem, however, was labor for agriculture, the mainstay of the southern economy. Increasingly the freedmen, whose work day was from sunrise to sunset, refused to work more than a half day, if at all, on Saturday. ... The greatest loss to the labor force resulted from the decision of growing numbers of negro women to devote their time to their homes and children."
- Emmer, "The Price of Freedom" (1992), pp. 35–36.
- Cohen, At Freedom's Edge (1991), pp. 16–17.
- Cohen, At Freedom's Edge (1991), p. 14.
- Emmer, "The Price of Freedom" (1992), p. 29.
- Wilson, Black Codes (1965), p. 53. "Most southern towns were not very large and the influx of even a few hundred undoubtedly gave witnesses a false impression of the size of the movement. ... Nonetheless impressions of southerners had great importance because they encouraged the belief that special laws—Black Codes—were necessary. This opinion was expressed by the Tallahassee Semi-Weekly Floridian, January 9, 1866: 'To live in town ... is now the general desire on the part of the freedmen ... a good vagrant system cannot too soon be put in operation.'"
- Stewart, Black Codes and Broken Windows (1998), pp. 2259–2260.
- Griffin, Rebecca J (April 2004). "'Goin' Back Over There to See That Girl': Competing Social Spaces in the Lives of the Enslaved in Antebellum North Carolina". Slavery & Abolition. 1 (25): 99.
- Daniel, "Metamorphosis of Slavery" (1979), p. 91. "Freedmen, however, did not cooperate with the plans to reenslave them. Immediately, planters and whites in general were struck by the change in attitude among freedmen. Deference largely disappeared, respect for whites dwindled, and even the more patient whites found it difficult to work with free blacks. Paternalism no longer worked, and whites came to hate freedmen, projecting on blacks the defeat in battle, economic ruin and the occupation by Union troops. […] Yet a kind of paternalism emerged once again during the violence of Radical Reconstruction, during the rides of the Ku Klux Klan. Planters, sizing up the situation, gave tenants on their plantations protection in exchange for regular work and a general compliance with the new order."
- Wilson, Black Codes (1965), p. 63.
- Richardson, "Florida Black Codes" (1969), pp. 371–372. "The convention responded with a special ordinance providing for a vagrancy law until the legislature could take action. Any able-bodied person who was 'wandering or strolling about or leading an idle, profligate, or immoral course of life' could be arrested upon complaint of any citizen before a justice of peace or circuit court judge. Penalties included imprisonment, fine, or being sold to the highest bidder for as much as twelve months."
- Wormser, The Rise and Fall of Jim Crow (2003), p. 8.
- Stewart, Black Codes and Broken Windows (1998), p. 2261.
- Cohen, At Freedom's Edge (1991), p. 33. "Of the nine states that adopted vagrancy laws in 1865 – 1866, all except North Carolina provided for the hiring-out of vagrants. These same states also enacted convict laws allowing for the hiring-out of other country prisoners who could not pay their fines and costs. In addition, Alabama, Georgia, South Carolina, Texas, and Virginia made it legal for county authorities to put prisoners to work on public projects such as roads and bridges."
- Forehand, Striking Resemblance (1996), pp. 59–60.
- Richardson, "Florida Black Codes" (1969), p. 373.
- DuBois, Black Reconstruction (1935), p. 172.
- Wilson, Black Codes (1965), p. 56. Quote: "Mississippi quickly passed one law providing for the immediate organization of volunteer militia companies and another outlawing possession of weapons by Negroes. The militia proceeded to disarm the Negroes in such a brutal fashion as to cause much criticism. Alabama Negroes were disarmed by similar methods with like results."
- Samuel W. McCall, Thaddeus Stevens; Boston: Houghton, Mifflin, & Co., 1899; pp. 253–254. Quoted in DuBois, Black Reconstruction (1935), p. 179.
- Forehand, Striking Resemblance (1996), p. 14.
- Ranney, In the Wake of Slavery (2006), p. 51. Quote: "Generally, Restoration legislatures tried to preserve as many prewar restrictions as possible while making at least a slight bow to Northern public opinion."
- Ellis Paxson Oberholtzer, A History of the United States since the Civil War (1917) 1:128–129. Quote: "Negroes must make annual contracts for their labor in writing; if they should run away from their tasks, they forfeited their wages for the year. Whenever it was required of them they must present licenses (in a town from the mayor; elsewhere from a member of the board of police of the beat) citing their places of residence and authorizing them to work. Fugitives from labor were to be arrested and carried back to their employers. Five dollars a head and mileage would be allowed such negro catchers. It was made a misdemeanor, punishable with fine or imprisonment, to persuade a freedman to leave his employer, or to feed the runaway. Minors were to be apprenticed, if males until they were twenty-one, if females until eighteen years of age. Such corporal punishment as a father would administer to a child might be inflicted upon apprentices by their masters. Vagrants were to be fined heavily, and if they could not pay the sum, they were to be hired out to service until the claim was satisfied. Negroes must not carry knives or firearms unless they were licensed so to do. It was an offence, to be punished by a fine of $50 and imprisonment for thirty days, to give or sell intoxicating liquors to a negro. When negroes could not pay the fines and costs after legal proceedings, they were to be hired at public outcry by the sheriff to the lowest bidder...."
- Novak, Wheel of Servitude (1978), p. 2–3.
- Forte, Spiritual Equality (1998), p. 600–601. "As with slaves, should the apprentice leave his master's employ, the master was authorized to pursue and recapture the youngster. If the apprentice still refused to return without just cause, he would be arrested and imprisoned."
- "Black Code of Mississippi", in The American Nation: Primary Sources, ed. Bruce Frohnen; Indianapolis: Liberty Fund, 2008.
- Novak, Wheel of Servitude (1978), p. 3. "The next act passed by the legislature dealt with 'Master and Apprentice' relationships 'as relates to Freedmen, Free Negroes and Mulattoes.' It allowed the probate courts to apprentice any black child whose parents could not or would not support him. First preference in the assignment of masters should go to the former owner of said minors."
- Forte, "Spiritual Equality" (1998), p. 603.
- Novak, Wheel of Servitude (1978), p. 4.
- Novak, Wheel of Servitude (1978), pp. 4–5. "Notably, the use of criminal penalties to prevent the enticement of a servant or his harboring was not included in the South Carolina codes at this time."
- DuBois, Black Reconstruction (1935), p. 176.
- Forte, "Spiritual Equality" (1998), pp. 601–602.
- Ranney, In the Wake of Slavery (2006), p. 46.
- Memorial: To the Senate and House of Representatives of the United States, in Congress Assembled, State Convention of the Colored People of South Carolina, November 24, 1865, pp. 30–31.
- DuBois, Black Reconstruction (1935), p. 231.
- Williamson, After Slavery (1965), p. 74.
- Williamson, After Slavery (1965), p. 75.
- Williamson, After Slavery (1965), pp. 76–77.
- Williamson, After Slavery (1965), p. 77.
- Williamson, After Slavery (1965), p. 78.
- Williamson, After Slavery (1965), p. 79.
- Novak, Wheel of Servitude (1978), p. 5. "The vagrancy law, which made no racial distinctions, was broadened in its compass, and provision was made for the hiring out of convicted vagrants (here an out was given to those who could convince a judge of their good behavior and future industry, obviously to provide a safety valve for convicted whites) and the penalty was raised from six months to a year. Enticement, harboring, or employing 'runaway servants' was made a penal offense, and the legislature added a new twist, demanding that all employers be shown a written discharge from the laborer's former master.
- DuBois, Black Reconstruction (1935), p. 177.
- Richardson, "Florida Black Codes" (1969), p. 365.
- Richardson, "Florida Black Codes" (1969), p. 366.
- Richardson, Florida Black Codes (1969), p. 374.
- Richardson, "Florida Black Codes" (1969), p. 375.
- Richardson, Florida Black Codes (1969), pp. 376–377.
- Ranney, Joseph A. (2006). In the Wake of Slavery. Praeger. p. 48. ISBN 0-275-98972-0.
- Crouch, "All the Vile Passions" (1993), p. 21.
- Crouch, "All the Vile Passions" (1993), p. 23. "The legislature prohibited blacks from marrying whites or testifying against them, serving on juries, holding office, voting, homesteading on the public domain, and serving in the militia, and confined public education to white children. It provisionally authorized the Board of Managers to purchase twenty-six acres of land for a 'Lunatic Asylum' for the benefit of 'Insane Negroes', if it was deemed 'expedient' to do so. They set aside $10,000 to buy the property and make improvements."
- Crouch, "All the Vile Passions" (1993), p. 24.
- Crouch, "All the Vile Passions" (1993), pp. 26–28.
- Crouch, "All the Vile Passions" (1993), p. 30.
- Forehand, "Striking Resemblance" (1996), p. 41.
- Forehand, "Striking Resemblance" (1996), p. 61.
- Forehand, "Striking Resemblance" (1996), p. 9.
- Forehand, "Striking Resemblance" (1996), pp. 42–43, 54.
- Forehand, "Striking Resemblance" (1996), pp. 49–50.
- Forehand, "Striking Resemblance" (1996), p. 13.
- Forehand, "Striking Resemblance" (1996), p. 50.
- Forehand, "Striking Resemblance" (1996), p. 57.
- Forehand, "Striking Resemblance" (1996), p. 51.
- Forehand, "Striking Resemblance" (1996), pp. 71–72.
- Forehand, "Striking Resemblance" (1996), p. 39–40, 62.
- Forehand, "Striking Resemblance" (1996), p. 58.
- Forehand, "Striking Resemblance" (1996), p. 56–57.
- Cohen, At Freedom's Edge (1991), p. 31.
- Forehand, "Striking Resemblance" (1996), p. 53.
- Forehand, "Striking Resemblance" (1996), p. 76.
- Forehand, "Striking Resemblance" (1996), p. 77.
- Forehand, "Striking Resemblance" (1996), pp. 77–78.
- Forehand, "Striking Resemblance" (1996), p. 3.
- Forehand, "Striking Resemblance" (1996), p. 102.
- Forehand, "Striking Resemblance" (1996), p. 107.
- Forehand, "Striking Resemblance" (1996), p. 108.
- Forehand, "Striking Resemblance" (1996), pp. 112–113.
- Forehand, "Striking Resemblance" (1996), pp. 105–106.
- Forehand, "Striking Resemblance" (1996), p. 117.
- Forehand, "Striking Resemblance" (1996), pp. 13, 109.
- Tsesis, The Thirteenth Amendment and American Freedom (2004), pp. 64–66.
- Forehand, "Striking Resemblance" (1996), p. 4.
- Wilson, Black Codes (1965), p. 66.
- Forte, "Spiritual Equality" (1998), p. 604.
- Forte, "Spiritual Equality" (1998), p. 605–608.
- Wormser, The Rise and Fall of Jim Crow (2003), p. 9.
- Ranney, In the Wake of Slavery (2006), p. 142.
- David Pilgrim, "What Was Jim Crow?", Jim Crow Museum of Racist Memorabilia (Ferris State University), 2000/2012.
- Cohen, "Negro Involuntary Servitude in the South" (1976), pp. 31–32. "Contained in embryo in the Black Codes and gaining increasing strength in the years immediately after Reconstruction, the system of involuntary servitude remained largely hidden until 1907."
- Daniel, "Metamorphosis of Slavery" (1979), pp. 89, 96.
- Forehand, "Striking Resemblance" (1996), p. 2.
- Forehand, "Striking Resemblance" (1996), p. 53–53.
- Stewart, "Black Codes and Broken Windows" (1998), p. 2262.
- Goluboff, "Lost Origins of Civil Rights" (2001), p. 1657–1658.
- Forte, "Spiritual Equality" (1998), p. 609.
- Daniel, "Metamorphosis of Slavery" (1979), p. 97.
- Daniel, "Metamorphosis of Slavery" (1979), p. 89. "It came as a shock, then, in 1901, when a new kind of slavery was discovered. It was called peonage after the labor practice in Mexico and through an unlikely set of circumstances violated an 1867 federal state in the United States. The law lay dormant for thirty-four years, but peonage was widespread in the South by the turn of the century, and it was especially virulent in the cotton belt, the Mississippi Delta, and the turpentine belt."
- Stewart, "Black Codes and Broken Windows" (1998), p. 2263.
- Stewart, "Black Codes and Broken Windows" (1998), pp. 2263–2264.
- Stewart, "Black Codes and Broken Windows" (1998), pp. 2268–2270.
- Bruce A. Dixon, "Black Mass Incarceration – Is It New? Is It Jim Crow? Is the Prison-Industrial Complex Real? And What Difference Does It Make", Black Agenda Report, 27 March 2013.
- Jaron Browne, "Rooted in Slavery: Prison Labor Exploitation"; Race, Poverty & Environment 14(2), 2007; reprinted in 17(1), Spring 2010.
- Daniel, "Metamorphosis of Slavery" (1979), p. 95.
- Daniel, "Metamorphosis of Slavery" (1979), pp. 93–94.
- Daniel, "Metamorphosis of Slavery" (1979), p. 94."Yet West Indian planters were not as successful as were southern planters in perpetuating involuntary servitude among freedmen. Despite vagrancy and contract laws in Jamaica, compulsion did not work. […] In the United States the legal machinery and violence were more successful in forcing plantation laborers to work."
- Emmer, "The Price of Freedom" (1992), p. 23. "By breaking their colonial links, the undeveloped or underdeveloped countries in Asia and Africa were expected to be able finally to follow the path of sustained economic growth that Europe and North America had walked in the past. In reality, the act of decolonization itself did not change the economic position of the newly independent countries, and in some cases decolonization actually slowed economic growth or even reversed it, because the scarce factors of production were used in creating an army or in experimenting with a different division of land."
- Emmer, "The Price of Freedom" (1992), pp. 26–28.
- Emmer, "The Price of Freedom" (1992), p. 24.
- Belz, Herman. A New Birth of Freedom: The Republican Party and Freedmen's Rights, 1861–1866. Westport: Greenwood Press, 1976; New York: Fordham University Press, 2000. ISBN 9780823220113
- Cohen, William. At Freedom's Edge: Black Mobility and the Southern White Quest for Racial Control, 1861–1915. Louisiana State University Press, 1991. ISBN 0-8071-1621-1
- Cohen, William. "Negro Involuntary Servitude in the South, 1865–1940: A Preliminary Analysis." Journal of Southern History 42(1), February 1976. Accessed via JStor, 29 June 2013.
- Crouch, Barry A. "'All the Vile Passions': The Texas Black Code of 1866". Southwestern Historical Quarterly 97(1), July 1993. Accessed via JStor, 9 July 2013.
- Daniel, Pete. "The Metamorphosis of Slavery, 1865–1900". Journal of American History 66(1), June 1979. Accessed via JStor, 4 July 2013.
- DuBois, W. E. B. Black Reconstruction: An Essay Toward a History of the Part Which Black Folk Played in the Attempt to Reconstruct Democracy in America, 1860–1880. New York: Russell & Russell, 1935.
- Emmer, Pieter C. "The Price of Freedom: The Constraints of Change in Postemancipation America". In The Meaning of Freedom: Economics, Politics and Culture After Slavery, ed. Frank McGlynn & Seymour Drescher. University of Pittsburgh Press, 1992. ISBN 0-8229-3695-X
- Forehand, Beverly. "Striking Resemblance: Kentucky, Tennessee, Black Codes and Readjustment, 1865–1866". Western Kentucky University, Masters Thesis, accepted May 1996.
- Forte, David F. "Spiritual Equality, the Black Codes, and the Americanization of the Freedmen". Loyola Law Review 43, 1998; pp. 569–611.
- Goluboff, Risa L. "The Thirteenth Amendment and the Lost Origins of Civil Rights". Duke Law Journal 50; 1609–1685.
- Novak, Daniel A. The Wheel of Servitude: Black Forced Labor after Slavery. University Press of Kentucky, 1978. ISBN 0813113717
- Painter, Nell Irvin. Creating Black Americans: African-American History And Its Meanings, 1619 to the Present. Oxford University Press, 2005. ISBN 9780195137552
- Ranney, Joseph A. In the Wake of Slavery: Civil War, Civil Rights, and the Reconstruction of Southern Law. Westport, CT: Praeger, 2006. ISBN 0-275-98972-0
- Richardson, Joe M. "Florida Black Codes". Florida Historical Quarterly 47(4), April 1969; pp. 365 – 379. Accessed via JStor, 29 June 2013.
- Stewart, Gary. "Black Codes and Broken Windows: The Legacy of Racial Hegemony in Anti-Gang Civil Injunctions". Yale Law Journal 107(7), May 1998; pp. 2249–2279. Accessed via ProQuest, 4 July 2013. (Also see EBSCO Host.)
- Tsesis, Alexander. The Thirteenth Amendment and American Freedom: A Legal History. New York University Press, 2004. ISBN 0814782760
- Williamson, Joel. After Slavery: The Negro in South Carolina During Reconstruction, 1861–1877. University of North Carolina Press, 1965.
- Wilson, Theodore Brantner. The Black Codes of the South. University of Alabama Press, 1965.
- Wormser, Richard. The Rise and Fall of Jim Crow. Macmillan, 2003. ISBN 9780312313265
- Birnbaum, Jonathan and Taylor, Clarence, eds. (2000). Civil Rights Since 1787: A Reader on the Black Struggle, New York University Press ISBN 0-8147-8215-9
- Foner, Eric. Reconstruction: America's Unfinished Revolution 1863–1877 (Harpercollins: 1988) ISBN 0-06-015851-4
- Horton, James Oliver and Horton, Lois E. (1998). In Hope of Liberty: Culture, Community and Protest among Northern Free Blacks, 1700–1860
- Litwack, Leon F. (1998). Trouble in Mind: Black Southerners in the Age of Jim Crow, Alfred A. Knopf
- Litwack, Leon F. (1980). Been in the Storm So Long: The Aftermath of Slavery Pulitzer Prize ISBN 0-394-74398-9
- Lowery,Charles D. and Marszalek, John F. (1992). Encyclopedia of African-American Civil Rights: From Emancipation to the Present Greenwood Press
- Middleton, Stephen (1993). The Black Laws in the Old Northwest : A Documentary History
- Oberholtzer, Ellis Paxson (1917). A History of the United States since the Civil War, New York, Macmillan Company
- Waldrep, Christopher (1996). "Substituting Law for the Lash: Emancipation and Legal Formalism in a Mississippi County Court" Journal of American History 1996 82(4): 1425–1451. ISSN 0021-8723 Fulltext: in Jstor. Actual operation of the codes in Mississippi courts.
Text of laws
- 1865 Black Codes of Mississippi
- "An Act to Establish and Regulate the Domestic Relations of Persons of Color..." or the Black Codes of South Carolina, December 1865
- Black Codes in the Former Confederate States
- Texas State Historical Association: Black Codes by Carl H. Moneyhon
- Black codes and Jim Crow laws in South Carolina
- Slavery by Another Name by Doug A. Blackmon
- The Southern "Black Codes" of 1865–66 Article, Discussion Questions, and Activity from Constitutional Rights Foundation
- The Illinois Black Code by Roger D. Bridges (pre-1865) |
Critical thinking—systematically evaluating information inputs—is an important managerial requirement in today’s dynamic world. A decision-maker is subjected to an information overload, each seeming to suggest a different problem and a different solution. This simulation requires a manager to differentiate between real problems and symptoms, devise alternate solutions, and measure the impact of those solutions. Our paper will provide details of the problem evaluation tools and techniques our team encountered in the simulation as well as the techniques utilized to evaluate the decision making process outcomes. Finally, our team will discuss what changes in the decision making techniques that could have generated better results.
Critical Thinking Simulation
“Now, more than ever, managerial decisions have far-reaching consequences in the way that organizations fail or succeed in bridging commerce and compassion, sustainability and profitability, and move from vision to effective strategic implementation. Solving problems, making decisions, and picking the courses of action are the most critical aspects of being in charge because it is risky and very difficult" (Safi and Burrell, 2007). A bad or unethical decision can be damaging to a company and a career. High level decisions usually require someone reviewing the companies overall goals and objectives to align the solution with the problem. Bad decisions are usually made when critical thinking is not a part of the decision-making process or other human factors such as personalities, assumptions and perceptions are used in the decision making process.
Critical Thinking in the Decision Making Process
“Critical thinkers: distinguish between fact and opinion; ask question; make detailed observations; uncover assumptions and define their terms; and make assertions based on sound logic and solid evidence” (Ellis, D. Becoming a Master Student, 1997). Critical thinking helps to ask the right questions, gather information and analyze the problem to make the best decision. Managers must apply experience-based and team-based decisions to solving a problem. “Critical thinking in leadership decision-making is about developing the ability to cut through the clutter of information, myths, assumptions, and buzz words to consider a variety of variables and possible scenarios” (Spitzer and Evans, 1997). Continuously asking questions will challenge team members during the decision making process to think creatively and avoid assumptions. Critical thinking helps develop a best case solution to a critical problem when using three critical steps. The three steps consist of framing the problem, making the decision and evaluating the decision. Many tools and techniques are generally used in making a decision. Managers may use one or more tools and techniques to make a decision.
Framing the problem
When framing the problem managers must identify the problem, define goals and objectives as well as evaluate the overall outcome of the problem on the company and determine if the problem is worth solving. Making the decision
Making the decision has more components than any of the other steps. Managers must first identify the cause of the problem, determine possible solutions and evaluate the impact as it relates to cost and customer satisfaction and finally determine a cost effective solution. When a manager challenges the team to identify the problem, they could look at sales data and customer trends to figure out the cause of the problem. Several tools and techniques can be utilized in making the decision.
Evaluating the decision
Evaluating the decision is the final step in using critical thinking in the decision making process. The decision is implemented based on the steps identified in making the decision. This step requires managers and teams to create an implementation plan. This implementation should include key issues, dates and... |
Why do vine leaves turn red, yellow or orange in autumn?
In autumn, when temperatures drop and the light decreases, the vine prepares for winter and the coming of the cold.
Chlorophyll, which is the source of the green color, starts to degrade and finally gives way to other pigments, such as the carotenoids that color the leaf in yellow-orange and the anthocyanins that provide colors ranging from red-orange to blue-purple.
Thus, depending on the brightness and the proportions of these pigments, the autumn leaves will take on one shade rather than another, until they become completely brown, the last stage before their fall and winter.
a u f i l d e l a v i g n e • |
Important Climate Change Mystery Solved by Scientists
Revised Holocene temperature record affirms role of greenhouse gases in recent millennia
Scientists have resolved a key climate change mystery, showing that the annual global temperature today is the warmest of the past 10,000 years – contrary to recent research, according to a Rutgers-led study in the journal Nature.
The long-standing mystery is called the “Holocene temperature conundrum,” with some skeptics contending that climate model predictions of future warming must be wrong. The scientists say their findings will challenge long-held views on the temperature history in the Holocene era, which began about 12,000 years ago.
“Our reconstruction shows that the first half of the Holocene was colder than in industrial times due to the cooling effects of remnant ice sheets from the previous glacial period – contrary to previous reconstructions of global temperatures,” said lead author Samantha Bova, a postdoctoral researcher associate in the lab of co-author Yair Rosenthal, a Distinguished Professor in the Department of Marine and Coastal Sciences and Department of Earth and Planetary Sciences at Rutgers University–New Brunswick. “The late Holocene warming was indeed caused by the increase in greenhouse gases, as predicted by climate models, and that eliminates any doubts about the key role of carbon dioxide in global warming.”
Scientists used marine calcareous (calcium carbonate-containing) fossils from foraminifers – single-celled organisms that live at the ocean surface – to reconstruct the temperature histories of the two most recent warm intervals on Earth. They are the Last Interglacial period from 128,000 to 115,000 years ago and the Holocene. To get the fossils, the scientists collected a core of bottom sediments near the mouth of the Sepik River off northern Papua New Guinea during the Rutgers-led Expedition 363 of the International Ocean Discovery Program. The core features rapidly accumulating sediments that allowed the scientists to recreate the temperature history of the western Pacific warm pool, which closely tracks changes in global temperatures.
How temperature evolved during the Last Interglacial and Holocene eras is controversial. Some data suggest that the average annual global temperature during modern times does not exceed the warmth in the Holocene’s early warm period, called the “Holocene thermal maximum,” which was followed by global cooling. Meanwhile, climate models strongly suggest that global temperatures have risen throughout the past 10,000 years.
“The apparent discrepancy between climate models and data has cast doubts among skeptics about the role of greenhouse gases in climate change during the Holocene and possibly in the future,” Rosenthal said. “We found that post-industrial warming has indeed accelerated the long and steady trend of warming throughout the past 10,000 years. Our study also underscores the importance of seasonal changes, specifically Northern Hemisphere summers, in driving many climate systems. Our method can, for the first time, use seasonal temperatures to come up with annual averages.”
Rutgers-affiliated co-authors include Shital P. Godad, a former Rutgers researcher now at National Taiwan University. Scientists at The Ohio State University and Nanjing Normal University contributed to the study. |
The History of Kevlar
As a protective element, Kevlar is still a relatively new product. Its origins begin in 1965 when DuPont decided that they wanted to manufacture a new tyre in order to save their customers money. Their aim was to make a tyre that was lighter and more durable than the tyres that the company sold at the time. There was an anticipated gas shortage looming and the company knew that if they could develop a stronger, longer-lasting tyre that helped diminish the amount of gas a car used, it would be hugely successful. DuPont hired Stephanie Kwolek to be in charge of a team of inventors who would develop the revolutionary material, Kevlar. After many trials and errors, Kwolek discovered that one of the materials they developed had extraordinary qualities about it.
Poly-p-Phenylene-terephthalate and polybenzamide were used to make a fibre that could withstand tension unlike any previously developed fibre, and Kwolek knew straight away that she and her team had developed something amazing. Kwolek took her fibre to a technician asked him to place the fibre on a “spinneret” – a machine used to test the strength of fibres. Charles Smullen, the technician, did not know how amazing the result of the testing would be. He placed the newly discovered fibre on the spinneret and was surprised to see that the fibre would not break during the testing. Previously used fibres such as nylon broke with little tension but this newly developed fibre could withstand tension that no other fibre could withstand. Kwolek immediately contacted her superiors to let them know about her revolutionary discovery. Instantly, they knew that she had developed something that would change the world. DuPont immediately established a polymer chemistry department and continued developing the fibre until 1971, when the world was finally introduced to Kevlar.
For many years, steel was the primary material used in the production of body armour. Steel offered great levels of protection but it was very cumbersome and made it difficult for individuals to move freely. Since its introduction, Kevlar has become the material that is most commonly used in the production of body armour. Kevlar is much lighter and more comfortable to wear than steel and offers five times the protection for its weight. It is now used by millions across the world and has saved many lives.
The use of Kevlar is not only limited to body armour. Kevlar is used in many items that we use on a daily basis, and most do not even realise. As its original production indented, Kevlar is used on tyres. The tyres used on bikes have an inner lining of Kevlar that provides them with the strength they need to be able to withstand punctures while someone is riding. Motorcycle enthusiasts are thankful for Kevlar because it is used in many of the jackets they wear on a daily basis. The elbow and shoulder padding found in many of the jackets is made of Kevlar and offers the riders protection if they get into an accident. Many people use a Smartphone on a daily basis without realising that some of the phones have a backplate that use Kevlar to help protect the inner mechanics of the phone. New uses for Kevlar are constantly being found and the world continues to be thankful for Kwolek’s discovery. |
After offering information about UV light and sun-protective behaviors, the two health-ed videos diverge: one describes the increased skin cancer risk of UV exposure and the other describes effects on appearance including wrinkles and premature aging. Which of these two videos do you think caused teenagers to use more sunscreen six weeks after it was shown?
“We see this anecdotally in the clinic. The teens who come in, often it’s because their parents are dragging them. A lot have undergone tanning or never wear sunscreen. You can tell that when we talk about the skin cancer risk, it doesn’t faze them. But when you talk about premature wrinkling and aging, they listen a little more closely,” says April W. Armstrong, MD MPH, investigator at the CU Cancer Center and vice chair of Clinical Research at the CU School of Medicine Department of Dermatology.
The current study aimed to quantify this observation. First, Armstrong and colleagues went to local high schools to recruit 50 subjects. All subjects completed questionnaires demonstrating their baseline knowledge about UV light and use of sun-protective behaviors. Then subjects were randomized into two groups, one of which viewed the health-based video that emphasized skin cancer risk, and the other of which viewed the appearance-based video that emphasized cosmetic changes due to UV exposure. Six weeks later, all subjects again completed questionnaires that showed the knowledge they retained and changes in sun-protective behaviors.
“Interestingly, we didn’t see any difference in teenagers’ knowledge — no matter if they had watched the health-based or appearance-based video, students learned and retained the same amount of information,” Armstrong says.
However, despite knowing the skin cancer risk from UV exposure, the group that had watched the health-based video showed no statistically significant increase in their sun-protective behaviors. On the other hand, the group that had been shown the appearance-based video reported a dramatic increase in the use of sunscreen.
“For teenagers, telling them UV exposure will lead to skin cancer is not as effective as we would hope. If our endgame is to modify their behavior, we need to tailor our message in the right way and in this case the right way is by highlighting consequences to appearance rather than health. It’s important to address now — if we can help them start this behavior when younger, it can affect skin cancer risk when older,” Armstrong says. |
How does a pressure sensor work?
Inside a pressure sensor, there is an element or diaphragm that, when pushed on by fluid or gases, responds electrically. This converts a mechanical change to an electrical change. The electrical response can be a change in output resistance, change of voltage, or change in current.
Why are pressure sensors used?
Pressure sensors monitor a process or system and send feedback to a controller. For example, if your process relies on a pump to keep it moving smoothly, a pressure sensor can monitor the actual pressure inside your system. If the pressure sensor detects that the system pressure is too low, it can send a signal to the pump and instruct it to speed up hence creating more pressure and keeping the machine running smoothly.
What are examples of pressure sensors?
Pressure sensors are broken down into two groups:
- Pressure Switches: On/off or digital output
- Pressure Transducers or Pressure Transmitters or Pressure Sensors: continuous or analog output
Pressure switches are simple on/off devices. Much like the light switch on the wall in your home. The electrical contacts are either open (and prevent current flow) or they are closed and allow the current to flow. As pressure rises and exceeds the pre-determined set point, the pressure switch will change state. If the contacts were open, they will close. If the contacts were closed, they will open.
Pressure Transducers / Pressure Transmitters / Pressure Sensors have a constant varying type of output, much like the light dimmer control in your home. As the sensor detects the pressure rising in your system, it will convert that pressure to a varying voltage or current output. This output can be sent to a controller or pump or display.
What type of sensor is pressure sensors?
There are three types of pressure sensors:
- Gauge pressure sensors:
- Utilize a breathing hole in the back of the sensor to allow the relative ambient pressure to not affect the output.
- If a gauge pressure sensor’s pressure port is open to the atmosphere (the air we breathe) and the barometric pressure changes, the sensor will not detect it. The change in pressure is seen on both sides of the sensor’s diaphragm and it negates the change.
- Sealed gauge pressure sensors:
- Are gauge pressure sensors but do not have a breathing hole in the back of them.
- Typically used when the measuring pressure range is at 1500 psi (100 bar) or above. With that, atmospheric pressure changes will have very little effect.
- Absolute pressure sensors:
- The back end of the sensor is sealed, and the chamber is evacuated from any air.
In this setup, if the sensor’s pressure port is open to the atmosphere, any changes in the atmospheric pressure will be measured by the sensor.
Learn More About Pressure Products:
Pressure Regulator, Solid State - 3100 Series Pressure Sensor
Traditional pressure regulators use a combination of internal nozzles
and springs to regulate how much pressure an application will be exposed
to down the service line. As the operator turns the mechanical
adjusting knob, a certain amount of pressure is allowed to pass thru the
regulator. If less pressure is required, the knob is adjusted again,
and less pressure is allowed thru.
Breathing Apparatus (SCBA) - 3100 Series Pressure Sensor
Human safety is the number one priority when working in oil fields or in
underground mines. Providing fresh air to the workers in these
environments relies on several critical systems working correctly to
ensure no harm comes to the workers. The worker will put on a
SCBA (or Self-Contained Breathing Apparatus) device over their face and |
The Afterschool Art Class recently explored the works of Pablo Picasso. It was a super fun lesson! We used:
- A short biography of Pablo Picasso
- Some examples of his portraits
- Small mirrors
- A chart of facial expressions
- Student weight paper
- Water colour paints
- Black permanent markers
We talked briefly about Picasso and some of his paintings and then I asked the children to complete their emotion charts by looking at their facial expressions in the small mirrors. When they had completed their charts I asked them to pick two different facial expressions to use in their portraits (Happy/Sad). Each was then asked to draw a practice portrait with two different emotions on either side of the face.
Once finished their practice portraits they were given the water-colour paper to begin their final piece. The pieces were painted using puck watercolour paints. Each student was instructed t use a variety of colours. When the art was dry students finished with an outline of their work.
Great work everyone! Next lesson: The Starry Night by Vincent Van Gogh |
In this chapter, you will learn about:
- Consumption Choices
- How Changes in Income and Prices Affect Consumption Choices
- How Consumer Choices Might Not Always be Rational
The 2008–2009 Great Recession touched families around the globe. In too many countries, workers found themselves out of a job. In developed countries, unemployment compensation provided a safety net, but families still saw a marked decrease in disposable income and had to make tough spending decisions. Of course, non-essential, discretionary spending was the first to go.
Even so, there was one particular category that saw a universal increase in spending world-wide during that time—an 18% uptick in the United States, specifically. You might guess that consumers began eating more meals at home, increasing grocery store spending; however, the Bureau of Labor Statistics’ Consumer Expenditure Survey, which tracks U.S. food spending over time, showed “real total food spending by U.S. households declined five percent between 2006 and 2009.” So, it was not groceries. What product would people around the world demand more of during tough economic times, and more importantly, why? (Find out at chapter’s end.)
That question leads us to this chapter’s topic—analyzing how consumers make choices and how changes affect those choices. For instance, do changes in prices matter more or less than changes in a consumer’s income? Can a small change in circumstances alter the consumers’ perception of a product or even of their own resources? While many choices may seem straightforward, there is often much more to consider.
Microeconomics seeks to understand the behavior of individual economic agents such as individuals and businesses. Economists believe that we can analyze individuals’ decisions, such as what goods and services to buy, as choices we make within certain budget constraints. Generally, consumers are trying to get the most for their limited budget. In economic terms they are trying to maximize total utility, or satisfaction, given their budget constraint.
Everyone has their own personal tastes and preferences. The French say: Chacun à son goût, or “Each to his own taste.” An old Latin saying states, De gustibus non est disputandum or “There’s no disputing about taste.” If people base their decisions on their own tastes and personal preferences, however, then how can economists hope to analyze the choices consumers make?
An economic explanation for why people make different choices begins with accepting the proverbial wisdom that tastes are a matter of personal preference. However, economists also believe that the choices people make are influenced by their incomes, by the prices of goods and services they consume, and by factors like where they live. This chapter introduces the economic theory of how consumers make choices about what goods and services to buy with their limited income.
The analysis in this chapter will build on the budget constraint that we introduced in the Choice in a World of Scarcity chapter. This chapter will also illustrate how economic theory provides a tool to systematically look at the full range of possible consumption choices to predict how consumption responds to changes in prices or incomes. After reading this chapter, consult the appendix Indifference Curves to learn more about representing utility and choice through indifference curves. |
Last week, NASA probe entered solar atmosphere! Now we will be able to study the biggest star supporting our solar system.
Decades of research has made it possible for us to witness this milestone! We are a step closer to understanding how the Sun supports life in the solar system, paving way for us to understand it better and study whether we are alone in the universe or is there life beyond us? What to study, what to look for when we search for life outside would be interesting as we progress!
Do you know?
- Unlike Earth, the Sun doesn’t have a solid surface. But it does have a superheated atmosphere, made of solar material bound to the Sun by gravity and magnetic forces.
- As rising heat and pressure push that material away from the Sun, it reaches a point where gravity and magnetic fields are too weak to contain it. That point, known as the Alfvén critical surface, marks the end of the solar atmosphere and beginning of the solar wind.
- What is solar wind? Solar material with the energy to make it across that boundary becomes the solar wind, which drags the magnetic field of the Sun with it as it races across the solar system, to Earth and beyond.
- Beyond the Alfvén critical surface, the solar wind moves so fast that waves within the wind cannot ever travel fast enough to make it back to the Sun – severing their connection.
- What is Sun’s corona? A corona is an aura of plasma that surrounds the Sun and other stars. The Sun’s corona extends millions of miles into outer space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph
- What is solar cycle? Sun’s 11-year activity cycle is known as the solar cycle.
- What are switchbacks? Switchbacks are the zig zag shaped structures in the solar wind
- Studies revealed that one spot where switchbacks originate is at the photosphere – the visible surface of the sun.
- Earth’s magnetic field acts like a solar wind shedding machine
- Understanding where and how the components of the fast solar wind emerge, and if they’re linked to switchbacks, could help scientists answer a longstanding solar mystery: how the corona is heated to millions of degrees, far hotter than the solar surface below.
Pictures and video source -> NASA.gov
Every piece of information we learn helps us understand our universe better. |
|Introduction to SQL – Image Source|
The SQL language is made up of several parts given below.
1. Data Definition Language (DDL)
The SQL DDL commands allow to define the schema (basic structure) of a table. It allows us to modify and delete the schemas also.
2. Data Manipulation Language (DML)
The SQL DML commands allow us to insert, delete and modify the tuples in the database.
3. Integrity Constraints Commands
These commands are basically part of the DDL commands. These commands allow us to specify integrity constraints. In the coming tutorials I will clear the concepts of integrity constraints with the help of examples.
4. View Definition
Some commands which are the part of DDL commands.
5. Authorization and Security
These DDL commands allow a user to specify the level of rights to access and modify the database. With the proper implication of authorization we can achieve the security in our database.
6. Transaction Control Language (TCL)
The SQL commands allow a user to control the transactions.
This was a brief introduction to SQL. In the next tutorial you will learn about data types in SQL. |
History of Retablos
Since literacy was scarce in the Middle Ages, churches began to incorporate stained glass windows depicting scenes from the Bible as a means of relating the message of the gospel to those without access to education. This is just one example of how images have been used in place of the written word particularly in the context of religion.
In Peru, Andean folk art has embraced storytelling through images with the construction of retablos. Retablos are three-dimensional boxes with figures inside, depicting a story of either religious significance or everyday life. In the same vein, nativities are figures set within a scene to tell the story of the birth of Jesus. So combining the Andean tradition of retablo with the story of the nativity is a natural meld.
Delicately handcrafted inside ornaments to hang on the Christmas tree, or in boxes for the mantle, Peruvian retablos will remind you of the true meaning of Christmas while at the same time, embracing the spirit of giving by supporting the artisans who make them, providing them with an opportunity to earn fair wages and a sustainable income.
Ten Thousand Villages works closely with artisans in towns including Ayacucho, Cuzco, and impoverished sections of Lima in order to help indigenous artisans preserve this cultural tradition. |
Ruby if, else and unless statement: The if expressions execute a single statement or a group of statements if a certain condition is met. It can not do anything if the condition is false. For this purpose else is used.
if conditional [then]
[elsif conditional [then]
Ruby if statement multiple conditions with example.
x = 10
if x > 8 then
puts "x is greater than 8"
x is greater than 8
Use of Multiple Conditions
If two things are true at the same time, then this section is for you. Below is an example:
if name == "David" && country == "UK"
If you like FreeWebMentor and you would like to contribute, you can write an article and mail your article to [email protected] Your article will appear on the FreeWebMentor main page and help other developers. |
In 1957, the Soviet Union launched Sputnik. The United States immediately responded by creating plans for a space program of its own. In fact, the first successful American satellite's launch predates NASA's creation. A few months later, on July 29, 1958, President Dwight Eisenhower signed the National Aeronautics and Space Act, which established NASA.
Four years later, President Kennedy announced that the United States would go to the moon by the end of the 1960s. To make his dream a reality, NASA created the Mercury and Gemini programs. The former established that humans were capable of space flight. The latter proved that humans could live in space for a short period of time. In 1969, the Apollo program put man on the moon.
After the Apollo program ended, NASA developed space stations to find out if humans can live in space for an extended period of time. It has also sent Voyagers 1 and 2 out of the solar system and sent multiple rovers to Mars. Along the way, NASA's discoveries have become a part of everyone's lives. For example, the LED light started as a NASA creation.
NASA's existed for 60 years. How many of those have you followed? Find out how much you know about the American space program with this quiz! |
- What are the five units of grammar?
- What are the five elements of grammar?
- What are the two types of grammar?
- What are the three types of grammar?
- How do I start grammar?
- What are the characteristics of grammar?
- What is your grammar?
- What are the 10 parts of speech?
- What are the basic rules of grammar?
- What is this in English grammar?
- Do we need grammar?
- What is the role of grammar in English?
- How many parts of grammar are there?
- What are the four views of grammar?
- What is importance of grammar?
- What is basic English grammar?
- What are the main parts of grammar?
- What is the use of grammar?
What are the five units of grammar?
There are five fundamental units of grammatical structure: morpheme, word, phrase, clause, and sentence.
Morphemes – units of sound that have meaning (cats..
What are the five elements of grammar?
Word order. Word order is the most important element of what is known as syntax. … Punctuation. Punctuation is another main element of syntax. … 3 Tense and aspect. Tense and aspect are the most import parameters applying to verbs; and verbs are fundamental to all statements. … 4 Use of determiners. … 5 Use of connectors.
What are the two types of grammar?
One basic distinction worth making is that between descriptive grammar and prescriptive grammar (also called usage). Both are concerned with rules–but in different ways. Specialists in descriptive grammar examine the rules or patterns that underlie our use of words, phrases, clauses, and sentences.
What are the three types of grammar?
Kinds of grammar.prescriptive.descriptive.transformational-generative.
How do I start grammar?
Here are 8 steps to learn grammar easily on your own.#1 Learn as many words as you can. To learn grammar easily, the basic element of any language is words. … #2 Talk to people. … #3 Watch and learn. … #4 Ask for corrections. … #5 Know the parts of speech. … #6 Look for patterns. … #7 Practice verb forms. … #8 Use an app.
What are the characteristics of grammar?
The main characteristics of traditional grammar relate to usage, diction, style and punctuation.Usage: Parts of Speech. Traditional grammar organizes words based on eight different parts of speech. … Diction. Diction is the proper use of words. … Style: Sentence Structure. … Style: Spelling. … Proper Punctuation.
What is your grammar?
In grammar, “your” is a possessive determiner. (Other possessive determiners are “my,” “your,” “his,” “her,” “its,” “our,” and “their.”) The word “your” sits before another word (usually a noun or a pronoun) to show: It belongs to “you.” For example: your car, your arm, your dog.
What are the 10 parts of speech?
Commonly listed English parts of speech are noun, verb, adjective, adverb, pronoun, preposition, conjunction, interjection, numeral, article, or determiner.
What are the basic rules of grammar?
Key RulesUse Active Voice. … Link Ideas with a Conjunction. … Use a Comma to Connect Two Ideas As One. … Use a Serial Comma in a List. … Use the Semicolon to Join Two Ideas. … Use the Simple Present Tense for Habitual Actions. … Use the Present Progressive Tense for Current Action. … Add “ed” to verbs for the Past Tense.
What is this in English grammar?
Generally speaking, we use this/these to refer to people and things, situations and experiences that are close to the speaker or very close in time. We use that/those to refer to people and things, situations and experiences that are more distant, either in time or physically. This is a great game.
Do we need grammar?
Grammar isn’t a bunch of arcane rules invented by pedants to trip students up. It’s a system of language — building sounds into words, words into phrases, phrases into sentences — most of which you already know. Grammar is what makes language work as a means of communication. … And that’s why grammar is important.
What is the role of grammar in English?
Grammar is the sound, structure, and meaning system of language. They recognize the sounds of English words, the meanings of those words, and the different ways of putting words together to make meaningful sentences. …
How many parts of grammar are there?
There are eight parts of speech in the English language: noun, pronoun, verb, adjective, adverb, preposition, conjunction, and interjection. The part of speech indicates how the word functions in meaning as well as grammatically within the sentence.
What are the four views of grammar?
They are: (1) grammar as a description of syntactic structure, (2) grammar as prescriptions for how to use structures and words, (3) grammar as rhetorically effective use of syntactic structures, and (4) grammar as the functional command of a sentence structure that enables us to comprehend and produce language (p. 2).
What is importance of grammar?
Grammar is important because it provides information that helps the reader’s comprehension. It is the structure that conveys precise meaning from the writer to the audience. Eliminate grammatical errors from your writing, and reward your readers with clear communication.
What is basic English grammar?
English grammar is defined as the body of rules that describe the structure of words, phrases, clauses, and sentences in the English language. … Developing a solid foundation in basic English grammar helps you construct sentences correctly and makes it easier to improve both your spoken and written communication skills.
What are the main parts of grammar?
Definitions of Key Grammar ConceptsParts of Speech. In English grammar, the eight major parts of speech are noun, pronoun, adjective, verb, adverb, preposition, conjunction, and interjection.Nouns. The easy way to remember nouns is that they refer to people, places, or things. … Pronouns. … Adjectives. … Verbs. … Prepositions. … Conjunctions. … Interjections.More items…•
What is the use of grammar?
Outside linguistics, the term grammar is often used in a rather different sense. It may be used more broadly to include conventions of spelling and punctuation, which linguists would not typically consider as part of grammar but rather as part of orthography, the conventions used for writing a language. |
Native to the California coast and the California/Nevada state line, the Myrtle’s silverspot butterfly feeds on the nectar of the monardella flowers. One of 33 species of birds listed as threatened or endangered by the State of California or the federal government, the western snowy plover is in jeopardy of disappearing from the dunes. in 2017, two years after treatment, the southwest side of the herbicide treatment area shows little regrowth of invasive plants. Sandy dunes along the California coast often feature hardy European beachgrass and a succulent, freeway iceplant, that many assume is part of the native flora. However, these groundcover plants were originally introduced in the 1800s by Gold Rush settlers who were hoping to keep sand from moving to the nearby roads, railroads and land. Today, they are invasive species that out-compete the native plants and the animals that live there. Over the years, the invasives took over the native Tidestrom lupine and beach layia, causing them to be placed on the federally endangered species list. The endangered Myrtle’s silverspot butterfly and the threatened snowy plover are dependent on native plants like these, and today, they too are in jeopardy of disappearing from the area. “Snowy plovers naturally select open areas to nest so that they can more easily spot predators,” said CDFW Environmental Scientist Laird Henkel. “The European beachgrass spreads quickly making the dunes less desirable as a place for these birds to nest.” Scientists determined that removing these invasive plants would be the best way to restore the dunes and the ecosystem that depends on them. To this end, CDFW awarded $54,000 in Environmental Enhancement funds to a project on the Point Reyes North Great Beach, located in Marin County, to restore the native sand dune plants on a 13-acre area in 2015. The fund committee selected the Point Reyes application because of the success of their previous dune restoration projects. Point Reyes National Seashore staff oversaw the removal of the invasive plants on the dunes. Their contractors spray-treated the dunes with an herbicide and uprooted the invasives by hand; they worked during times of low winds and no rain, to protect other natural plants, wildlife, nearby farms and the public from overspray. Point Reyes scientists monitored the treated area with an easy-to-use mapping tool called photo point monitoring – an effective method of monitoring vegetation and ecosystem change. Visual surveys and the mapping program showed just a one-to-three percent regrowth of the invasive plants over time, while previous restoration projects showed much more regrowth. “The project area represents a vital link between earlier restoration efforts near Abbotts Lagoon and new restoration efforts at the AT&T cell tower area, enabling the park to move closer towards its goal of several miles of dune habitat not wiped out by invasive plants such as European beachgrass and iceplant,” said Point Reyes National Seashore Ecologist Lorraine Parsons. CDFW-OSPR and the Point Reyes staff consider the project’s first objective – eradicating invasive European beachgrass and ice plant – a success. Earlier this year, scientists noticed in treated areas the reappearance of wild cucumber. The reappearance of other native plants such as the mock heather, California blackberry and yarrow, and wildlife is the second objective, the success of which will be determined over time. Other treated areas in the region show beachgrass breakdown and increased native dune scrub and mat species after six years. Photos courtesy of Point Reyes National Seashore and the U.S. Fish and Wildlife Service. Top photo: The Point Reyes National Seashore staff oversee contractors spray-treating the dunes with an herbicide . |
Allergies affect 500 million people across the globe and in India the figure is growing larger each day. Studies have shown that three in every ten people in the capital of Delhi and NCR region suffer from nasal allergies. The Indian population is largely effected by Allergic Rhinitis and Hay Fever. Rhinitis is the irritation of the Nasal passages with swelling of mucous membrane in the nose. This also results in itchy and watery eyes with consistent sneezing leading to headaches apart from Asthma and Bronchitis.
Allergic Rhinitis usually results from tree, grass, weeds or pollen and is experienced during summer. Recurrent allergic rhinitis can cause year-round symptoms and irritation. This allergic reaction also results from indoor irritants such as feathers, mold spores, animal’s dander (hair and skin shed by pets), or mold spores carried in the air.
El Nino winds are also responsible for extremely wet and warm weather conditions that support the growth of fertile greenery breeding conditions for molds, which increases the count of pollen and mold spores in the environment and ultimately resulting in allergic reactions for people.
What is the real cause of Allergies? People inherit a certain genetic disposition towards allergies. Which means it’s passed down from Parents to children and so on. During spring, the immune system of the body is exposed to different allergens and forms allergy-specific antibodies (called immunoglobulins). These are present in the cells of your eyes, nose, lungs and skin. When an allergen and an antibody combine the body releases histamine and other chemical substances into the bloodstream which results in an allergic response. Pollen, dust, mold or other substances that can be inhaled, are common allergens that cause these symptoms.
Remedies that can help in case of Nasal Allergies are:
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Portions of the growing Earth may have been extraordinarily sluggish to change, with some pieces lasting for more than 1.5 billion years despite the influence of enormous heat and pressure found in the planet's interior, researchers say.
These new findings suggest Earth was less of a well-mixed melting pot and more like a motley salad bowl than previously thought.
Many aspects of the Earth's formation about 4.5 billion years ago remain mysterious because so few rocks from that time have survived. To learn more about the planet's distant past, researchers investigated ancient volcanic rocks — 2.82-billion-year-old ones from Russia and 3.47-billion-year-old ones from South Africa.
Our world emerged from the gradual collisions of bodies of increasing size over what may have been as much as tens of millions of years. Chemical elements then separated into different compartments of Earth's interior based on their affinity for iron.
The researchers discovered that the 2.8-billion-year-old volcanic rocks from Russia have a different makeup of tungsten isotopes compared to most rocks, including those contributing to the tungsten filaments in incandescent light bulbs. (Isotopes of elements have the same number of protons in their atomic nucleus, but different numbers of neutrons.)
The Russian rocks have more of the isotope tungsten-182, which is thought to come from the radioactive decay of an isotope of another element, hafnium-182. This hafnium-182 was present at the time our solar system formed, and rapidly decayed to tungsten-182 in about 60 million years. So the Russian rocks weren't cycled as quickly as other Earth rocks were.
"This difference in isotopic composition requires that the Earth formed and separated into a metallic core, silicate mantle, and perhaps crust, well within the first 60 million years of solar system history," said researcher Mathieu Touboul, a geochemist at the University of Maryland. "In itself this is not new or surprising."
"What is new and surprising is that a portion of the growing Earth developed the unusual chemical characteristics that could lead to the enrichment in tungsten-182, and also that this portion of the mantle remained distinct from the rest of the mantle for more than 1.5 billion years," Touboul added. "At this time it contributed material to the volcanic system we sampled."
This has implications for our understanding of how quickly the Earth became the Earth.
"Our results suggest that some portions of the Earth likely formed within 10 to 20 million years of the formation of the solar system, and that these earliest building blocks for the planet remained distinct until at least 2.8 billion years ago," Touboul told OurAmazingPlanet.
These findings of long-term survival of portions of the mantle conflicts with the conventional wisdom that, since the mantle of the early Earth must have been very hot, it was likely to have been well mixed.
"It has even been speculated that the outer, rocky portion of Earth was completely melted by a giant impact that created the moon," Touboul said. "Such conclusions are difficult to reconcile with our new findings."
Many questions remain, Touboul said: "We don't, for example, know whether the portion of the Earth with the unusual isotopic composition still exists," he noted. "In addition, the processes responsible for the formation of the earliest building of the Earth are still to be clearly identified. We plan to analyze some modern volcanic rocks and others old systems in the near future to assess these."
Touboul, with his colleagues Igor Puchtel and Richard Walker, detailed their findings online today (Feb. 16) in the journal Science.
This story was provided by OurAmazingPlanet, a sister site to SPACE.com. |
For preschoolers, every day comes with learning or driving home a new skill. As adults, it is often taken for granted how interesting it can be to teach children task that we see as simple – such as identifying colors and writing their name. However, if you had to explain to someone what “red” was, how would you go about it?
As such, preschool teachers and parents have to get a little creative when they are teaching young children concepts such as learning the alphabet. In this article, we are going to take a look at some activities that can be used to help preschool-aged children learn their alphabet.
Make a Game with an Alphabet Mat or Poster
Ideally, you want to teach your preschoolers to read and write. This is an end goal of children learning their letters. However, you can’t run before you can walk and the same goes for learning the alphabet. So, first, you need to make sure your preschoolers can recognize letters.
For this, you can quickly turn things into a game whether you are working with a single child or a full classroom. All you really need is an alphabet mat or poster – for a larger group of children a mat might work better.
The main idea behind this activity is to call out a letter and see if the children can find and identify it. If you want to take this activity a step further, you should ask the children the sound of the letter they just identified. This will help them to learn to associate the sounds that the letters make along with what the letters are.
Play “I Spy”
This is a particularly good activity for parents of preschoolers. Once a child starts to get a handle on their letters, you should see if they can point them out unprompted. After all, there are signs and writing everywhere, so you might as well incorporate it into your children’s lessons.
A fun idea is to focus on letters that are important to the child. For example, have them look for places where they see the first letter of their name. This way, you can teach them their letters and get them started on learning to spell their name!
In addition, this can be a fun pastime. One of the best times to do this activity is during a road trip. After all, you are surrounded by license plates and road signs, so you aren’t short of letters anywhere you look. You can even change this game up once they start learning to spell. For instance, at that point, instead of saying “can you point out the letter ‘M’?”, you might ask, “can you point out the first letter in the word ‘mom’?”.
Another fun game to play is bingo! To modify this game, you would switch the numbers that usually populate a bingo board with letters. However, since you are playing with preschoolers learning their letters, you will want to simplify the board a little bit.
By this, we mean simplify the multiple conditions on the board. When you play bingo traditionally, the numbers are usually called out with a precondition coordinating with the “bingo” tagline. In the traditional game, for example, the numbers wouldn’t just be called out as “23” and any 23 on the board could be marked. Instead, they are called out as something like “B23” and only a 23 in the B column would count.
When you create an alphabet version for preschoolers, try taking away the concept of columns. Rather, if you were to call out “B”, allow the children playing to mark any instance of “B” showing up on the board. This way, they are only focused on recognizing new letters rather than trying to learn superfluous rules at the same time.
Once children get a little more comfortable with their alphabet, you can always switch up the rules to stay on their skill level. Instead of simply calling out the letter “B”, for example, you could call out “lowercase B” or “uppercase B”.
Sort Your ABCs
Once a child starts to get their bearings on what each letter is. For example, if they can identify a letter by name, the next step is to make sure they can sort the letters into alphabetical order, words, and – eventually – sentences.
Simply making preschoolers write out letters and words, though, can get boring. Of course, using books to trace letters and words does work but it is rarely an activity that they enjoy, so the lesson can take longer to sink in.
An activity they might enjoy more is to use alphabet stickers or magnets. With these, you can instruct the preschooler to put the letters in a certain order. In addition, though, it gives children a chance to rearrange letters on their own as well and do one of small children’s favorite thing to do when they learn about something new – experiment. |
Round-ups and Deportations to Killing Centres
Related ImagesSee the photographs related to this lesson
Review the information on Jewish Councils (Judenräte) from the United States Holocaust Memorial Museum's website with students. Ask students what questions they have about the role of the Judenrat in the Lodz Ghetto.
Introduce Lawrence L. Langer's concept of "choiceless choice." Ask students to work in pairs to discuss and unpack how the concept of choiceless choice relates to the Lodz Ghetto's Jewish Council (Judenrat) and the role its chairman, Mordechai Chaim Rumkowski, played in the running of the Lodz Ghetto. Ask partner groups to report back to the class for a larger discussion.
Save the Last Word for Me
Make enough copies of each photograph so that each student can have one. For example, if you have a class of 30 students, make three copies of each image so you have a total of 30. Display the images on a table. At the start of the class, ask students to come to the table and select one image that interests them.
On a piece of paper or an index card, each student should write responses to the following questions: What stands out for you in this image? What do you think is happening? Why did you choose this image? Once they have completed this exercise, students with different images should get into groups of three and complete a Save the Last Word for Me strategy.
After students complete the Save the Last Word for Me exercise, transition to a whole-group discussion or journal-entry session. Some questions that you might want to use for this discussion or as a journal prompt are:
- What new information have you learned about the deportation of Jews from the Lodz Ghetto to the killing centres?
- How have these images altered or affirmed your knowledge about and understanding of the deportation of Jewish people from the Lodz Ghetto to killing centres?
- What evidence do you see of the humanity and struggle for survival of the residents of Lodz?
- How did the process of genocide attempt to strip the Jewish people of Lodz of their humanity? What evidence do you see?
- What evidence do you see of the leadership of Mordechai Chaim Rumkowski in the photographs of the roundups and deportation to killing centres?
- What are the moral and ethical implications of the "choiceless choices" the Jewish Council and Rumkowski faced in carrying out the edicts of the Nazis?
Information on the role of Jewish Councils in ghettos.
A short piece on the concept of "choiceless choices" by Lawrence L. Langer.
Transcript for "Give Me Your Children": Voices from the Lodz Ghetto. |
LET Reviewer: Principles and Strategies of Teaching Prof Ed
1. To ensure the lesson will go smoothly, Teacher A listed down the steps she will undertake together with those of her students. This practice relates to?
a. Teaching style
b. Teaching method
c. Teaching strategy
d. Teaching technique
2. The class of Grade 6 - Einstein is scheduled to perform an experiment on that day. However, the chemicals are insufficient. What method may then be used?
3. Teacher C gives the class specific topic as assignment which they have to research and pass the following day. However, the students could not find any information about it. What method should Teacher C use to teach the assignment?
a. Project method
b. Discovery approach
c. Lecture method
d. Demonstration method
4. Pictures, models and the like arouse students interest on the day's topic, in what part of the lesson should the given materials be presented?
a. Initiating activities
b. Culminating activities
c. Evaluation activities
d. Developmental activities
5. In Bloom's taxonomy of educational objectives, the domains are stated from lowest to highest level. Which of the following objectives belongs to the lowest level?
a. To identify the characters of the story.
b. To differentiate active from passive voice.
c. To give the available resources that could be recycled to useful things.
d. To explain the procedure in changing improper fraction to mixed number
6. The class of IV - Kalikasan is tasked to analyze the present population of the different cities and municipalities of the National Capital Region for the last five years. How can they best present their analysis?
a. By means of a table
b. By looking for a pattern
c. By means of a graph
d. By guessing and checking
7. There are several reasons why problem-solving is taught in Math. Which is the LEAST important?
a. It is the main goal for the study of Math
b. It provides the content in which concepts and skills are learned and applied
c. It provides an opportunity to develop critical and analytical thinking
d. It provides pupils an opportunity to relate Math in the real world
8. Teacher D teaches in a remote high school where newspapers are delivered irregularly. Knowing the importance of keeping the students aware of current affairs, what is probably the best way to keep the students updated?
a. Gather back issues of newspapers and let pupils compile them.
b. Urge the pupils to listen to stories circulating in the community.
c. Encourage the pupils to listen to daily broadcast from a transistor radio.
d. The teacher should try all available means to get the newspaper delivered to the school
9. Devices can make a lecture more understandable and meaningful. What is the most important thing a teacher should consider in the selection and utilization of instructional materials?
a. Objectives of the lesson
b. Availability of instructional materials
c. Attractiveness of instructional materials
d. Degree of interest on the part of the students
10. Teacher E asks student A to identify and analyze events, ideas or objects in order to state their similarities and differences. In which part of the lesson does said activity take place?
d. Comparison and Abstraction
11. Which part of the lesson is involved in the giving of situation or activities based on the concepts learned?
d. Comparison and Abstraction
12. Teacher F wants the class to find out the effect of heat on matter. Which method will help him accomplish his objective?
a. Project Method
b. Laboratory Method
c. Problem Method
d. Expository Method
13. In Math, Teacher G presents various examples of plane figures to her class. Afterwards, she asks the students to give definition of each. What method did she use?
14. Teaching Tinikling to I-Maliksi becomes possible through the use of?
a. Inductive Method
b. Expository Method
c. Demonstration Method
d. Laboratory Method
15. What is the implication of using a method that focuses on the why rather than the how?
a. There is best method
b. Typical one will be good for any subject
c. These methods should be standardized for different subjects.
d. Teaching methods should favor inquiry and problem solving.
16. When using problem solving method, the teacher can
a. Set up the problem
b. Test the conclusion
c. Propose ways of obtaining the needed data
d. Help the learners define what is it to be solved
17. Which of the following characterizes a well-motivated lesson?
a. The class is quiet.
b. The children have something to do.
c. The teacher can leave the pupils
d. There are varied procedures and activities undertaken by the pupils.
18. Learners must be developed not only in the cognitive, psychomotor but also in the affective aspect. Why is development of the latter also important?
a. It helps them develop a sound value system.
b. Their actions are dominated by their feelings.
c. It helps them develop an adequate knowledge of good actions.
d. Awareness of the consequences of their action is sharpened.
19. Which of the following attributes characterizes a learner who is yet to develop the concept?
a. The learner can identify the attributes of the concept.
b. The learner can summarize the ideas shared about the concept.
c. The learner can distinguish examples from non-examples.
d. The learner gets a failing grade in the tests given after the concept has been discussed.
20. The strategy which makes use of the old concept of "each-one-teach-one" of the sixty's is similar to?
a. Peer learning
b. Independent learning
c. Partner learning
d. Cooperative learning
21. Which part of the lesson does the learner give a synthesis of the things learned?
22. Educational objectives are arranged from simple to complex. Why is this?
a. Each level is built upon and assumes acquisition of skills from the previous level.
b. Objectives are broad and value-laden statements that lead to the philosophy of education.
c. Be idealistic and ambitious to begin with grandiose scheme for using taxonomy in all levels.
d. These are guidelines to be taught and learned where teachers and students evaluate learning.
23. Which of the following is NOT true?
a. Lesson plan should be in constant state of revision.
b. A good daily lesson plan ensures a better discussion.
c. Students should never see a teacher using a lesson plan.
d. All teachers regardless of their experience should have daily lesson plan.
24. In Music, Teacher 1 wants to teach the class how to play the piano in the Key of C. Which of the following should be his objective?
a. To play the piano in the key of C chords
b. To improve playing the piano in the key of C
c. To interpret property of chords of Key of C in the piano
d. To exhibit excellent playing of piano in the key of C
25. When using instructional material, what should the teacher primarily consider?
a. The material must be new and skillfully made.
b. It must be suited to the lesson objective.
c. The material must stimulate and maintain students' interest
d. It must be updated and relevant to Filipino setting.
Answers: 1B 2D 3C 4A 5A 6C 7A 8C 9A 10D 11C 12B 13A 14C 15D 16D 17D 18A 19A 20D 21C 22A 23C 24A 25B
Principles and Strategies of Teaching Part 2
1. Student A wishes to write a lesson plan. Which question should s/he asks herself/himself first?
a. What materials will I need?
b. How will I get things started?
c. What do I want to accomplish?
d. What exercises will I give my students?
2. Which of the following characterizes best an effective classroom manager? One who is friendly yet
3. Which of the classroom activities below is effective?
a. The concept learned is applicable to daily life.
b. The techniques and approaches used are varied.
c. The variety of instructional materials used is evident.
d. The laughter and enjoyment of students are contagious.
4. When is praise effective? When it
a. describes students present accomplishments
b. shows spontaneity, variety and other signs of credibility
c. focuses students attention on their own task relevant behavior
d. provides information to students about their competence and the value of their accomplishments
5. Which of the following is a divergent question?
a. How is water purified?
b. What are the parts of a sentence?
c. What is the most populated country in Asia?
d. What is the formula in getting the weight of an object?
6. Which of the following reading skill belongs to a higher level?
a. Drawing conclusion
b. Stating the main idea
c. Following directions
d. Noting specific details
7. Which of the following questions is classified as low level?
a. What is Science?
b. How is city differentiated from a province?
c. If given the chance to become a government official, what reform/s will you advocate? Why?
d. Who among the Filipino heroes and heroines do you like best? Explain.
8. Why does the teacher have to plan the day's activities?
a. This is expected by pupils.
b. This is required of a teacher.
c. The ability of the teacher is tested.
d. The accomplishment of the objectives is dependent of the plan
9. Which of the following should the teacher use to start the class discussion?
a. Narrow question
b. Convergent question
c. Memory question
d. Divergent question
10. What of the following characterizes best a well-managed class? When learners
a. are controlled by the teacher
b. blindly obey teachers' instructions
c. pursue their task without inhibition
d. are engaged in an activity that leads them to realize the set goal
11. Which of the following belongs to a lower-order thinking skills?
a. Teaching for meaning
b. Encouraging creativity
c. Asking convergent questions
d. Making the students aware of their mental processes
12. When should Teacher M undertake the task of setting up routine activities?
a. Every homeroom period
b. On the very first day of school
c. Every day at the start of the session
d. As soon as the students have adjusted to their schedule
13. Which of the following marks a conducive environment?
a. Excessive praise
b. Individual competition
c. Long assignments
d. Cooperative learning
14. Which of the following helps develop critical thinking?
a. Asking low-level questions
b. Blind obedience to authority
c. Asking convergent questions
d. Willingness to suspend judgment until sufficient evidence is presented
15.Teacher N wants to develop the comprehension skills of his pupils. How should his questioning proceed?
I. literal II. Interpretation III. Critical IV. Integration
a. I, II, III, IV
b. I, III, II, IV
c. I, II, IV, III
d. IV, III, II, I
16. Which of the following counters the teacher's role as facilitator of learning?
a. Does more talk than learners
b. Does less talk compared to learners
c. Makes use of interactive teaching strategies
d. Caters to multiple intelligence in the classroom
17. Which of the following practices violates the guidelines in asking questions?
a. Avoid cognitive memory questions
b. Call on pupils before asking the questions
c. Use probing questions to follow up incomplete answers
d. Sequence questions so that higher level questions build on the answers to lower level questions
18. Which of the following shows cooperation?
a. Doing all the work alone
b. Letting others copy from you
c. Collaborating with others in the group
d. Allowing others to dominate in the decision-making
19. Which of the following violates good discipline?
20. Asking a series of questions to a student is a violation of which technique in questioning?
a. Wait time
b. Prompting questions
d. Probing questions
21. Which of the following should Teacher O practice more if he wants to give his students the opportunity to think critically?
a. Provide questions with clues
b. Give questions that require analysis
c. Give questions that deviate from the main topic
d. Allow the children to ask questions during class discussion
22. Which guideline in asking questions must Teacher P use to develop reflective thought and critical thinking among her learners?
c. Wait time
23. Which of the following practices is an effective way to start a lesson?
a. Checking the attendance
b. Scolding someone who was late
c. Evaluating the work done the previous day
d. Reminding the pupils of standards of listening
24. Which of the following routines is the best way to start a class?
a. Ringing the bell
b. Greeting each other
c. Making the children line up
d. Asking the children to clean the room
25. What is the most effective way to distribute papers/ materials in class?
a. Give pupils papers one by one
b. Let pupils come to the teacher one by one
c. Ask a leader pupil to distribute the papers.
d. Instruct pupils to "Get one and pass".
Answers: 1C 2C 3A 4D 5A 6A 7A 8D 9D 10D 11C 12B 13D 14D 15A 16A 17B 18C 19D 20A 21B 22A 23C 24B 25D
Principles and Strategies of Teaching Part 3
1. Of goals of education, which relates to the strengthening of our society’s sense of belonging and identity?
C. Moral character
2. Of the following interventions, which is directly aimed at responding to the transitional gap between academicachievement and employment?
A. Deregulation of tuition fees
B. Voluntary accreditation of schools
C. School networking with business and industry
D. Identification of centers of excellence
3. Teacher Ernie makes sure that he covers the essential subject content, while treating them sufficiency or in-depth. What guiding principle is he following for lesson preparation?
4. As preventive measure for classroom discipline, the teacher may restructure the program. How is this not done?
A. Reteach lessons difficult to understand
B. Remove tension level before proceeding with lesson
C. Modify lesson
D. Skip whole lesson unit altogether
5. Teacher Jose talks to students about their interests, what they did over the weekend, their progress in school work, etc. What positive approach to classroom management did Teacher Jose apply?
A. Trusting students
B. Being fair and consistent
C. Expressing interest for students
D. Being positive
. Of the following, which is a non-threatening style of disciplining unruly students?
A. Stand under heat of the sun
B. Do push-ups
C. Send to guidance office
D. Squat before the class
7. Among mistaken goals in the Acceptance Approach to discipline, what happens when students seek to hurt others to make up being for being hurt or rejected?
A. Revenge seeking
B. Power seeking
D. Attention getting
8. Among mistaken goals in the Acceptance Approach to discipline, what happens when students are not getting the recognition they desire, continually seek help, and refuse to work unless the teacher hovers over them?
A. Attention getting
C. Revenge seeking
D. Power seeking
9. Among mistaken goals in the Acceptance Approach to discipline, what happens when students feel helpless and rejected so that they remove themselves rather than confront the situation?
B. Power seeking
C. Revenge seeking
D. Attention getting
10. To manage behavior, the teacher needs to be able to identify the mistaken goals of students. What is the hidden goal of students who become violent?
A. Goal is to seek power
B. Goal is to get attention
C. Goal is to isolate self
D. Goal is to get revenge
11. Facilities such as classrooms, fixtures, and equipment can often damage the morale of new teachers and become an obstacle for adapting well to the school environment. What should be the policy for assigning said physical facilities?
A. Needs of student’s basis
B. Position ranking basis
C. First-come, first-served basis
D. Service seniority basis
12. According to the guidelines on punishment, what does it mean if the teacher should give the student the benefit of the doubt?
A. Make sure facts are right before punishing
B. Doubt the incident really happened
C. Don’t punish and doubt effectiveness of punishment
D. Get the side of the students when punishing
13. Of subcategories of movement behavior, what is happening when the teacher ends an activity abruptly?
14. Which of the following is true of a democratic classroom?
A. Teacher acts as firm decision maker
B. Students decide what and how to learn
C. Consultation and dialogue
D. Suggestions are sent to higher officials for decisions
15. Which of the following steps should be completed first in planning an achievement test?
A. Set up a table of specifications
B. Define the instructional objective
C. Select the types of test items to use
D. Decide on the length of the test
16. Teacher Francis organized a structured class discussion with two opposing sides and assigned speakers on the issue of contraceptives. What was this kind of class?
C. panel discussion
17. Problems of discipline (misdeeds, lapses, minor offenses) can be reduced through enthusiasm which can be matched by the enthusiasm of learners. What can draw a laugh and reduce tension from all?
A. Verbal reinforces
B. Nonverbal gestures
D. Sense of humor
18. What best describes “puwede na” mentality vs. excellence in service/work?
A. Arduous preparation
B. Resignation to mediocrity
C. Committed work
D. Striving to be the best
19. If the children are cooperatively engaged with the teacher in a group project the children will discipline themselves as each member of the group exercises
A. Obedience to the teacher
B. Special interest
C. Peer influence
D. Moral compulsion
20. Which of these “combination of classes” is organized in places where the required number of pupils of the same grade levels has not met the required number to make up a separate class thus the teacher apportions class time for instruction to every grade level within the class?
Answers: 1D 2C 3A 4D 5C 6C 7A 8A 9A 10D 11A 12D 13B 14C 15B 16B 17D 18B 19C 20A
You can download Principles and Strategies of Teaching Prof Ed reviewer here. |
What is humanitarianism?
Explore the concept of humanitarianism and the shared qualities that make us human.
- Lesson plan, videos
- Humanitarianism and the Red Cross
By looking at the ideas of kindness and human dignity, this teaching resource explores what it really means to be a humanitarian. Discussion topics, group activities and a moving film help to develop learners’ sense of empathy and understanding of the topic.
- consider what makes us human
- explore the concept of humanitarianism and what it means to be a humanitarian
- discuss the idea of human dignity.
1. Starter activity: What makes us human?
Encourage learners to begin their exploration of humanitarianism, starting with the question “what makes us human?”
2. Humanitarianism is…
A group activity which provides learners with the opportunity to describe and define what humanitarianism means to them.
3. Unpacking humanitarianism
Learners develop their ideas about humanitarianism by engaging with different perspectives. They discuss a short video about humanity.
4. Human dignity
Explore the concept of human dignity, and how dignity can be respected and preserved through humanitarian action.
5. Being a humanitarian
Discover the values and skills that might be needed to act in a humanitarian way.
6. I am humanitarian
Finish with a moving video about humanity. Learners identify simple acts they could perform to take humanitarian action in their lives.
Video: Our world, your move for humanity
These resources were written by Rob Bowden and Rosie Wilson of Lifeworlds Learning. They were published in February 2015 and reviewed in September 2017.
The photo shows a boy in Iraq holding a box of relief items (© Mohammed Ghafur Ahmed Muayad/ICRC). |
*Condition results in red blistering skin that looks like a burn or a scald.
*Condition is caused by toxins from staph bacterial infection.
*Condition occurs mostly in children under the age of 5, particularly newborns.
Staphylococcal scaled skin syndrome (SSSS) is an illness characterized by red blistering skin that looks like a burn or a scald. SSSS is caused by the release of toxins from toxic strains of Staphylococcus aureus. The toxins cause skin molecules to come unstuck from one another. SSSS has also been called Ritter’s disease or Lyell’s disease when it appears in newborns or young infants.
SSSS occurs mostly in children younger than 5 years, particularly newborns. Lifelong protective antibodies against staph toxins are usually acquired during childhood which makes SSSS much less common in older children and adults. Lack of specific immunity to the toxins and an underdeveloped kidney flushing system lead to infection in infancy.
Immuno-deficient individuals and individuals with kidney failure, regardless of age, may also be at risk of SSSS.
SSSS starts from a staphylococcal infection. Outbreaks of SSSS often occur in childcare facilities. An adult carrier of staphylococcus aureus introduces the bacteria into the nursery. Staph bacteria is common and can live on skin with no adverse symptoms in the carrier. SSSS usually starts with fever, irritability and widespread redness of the skin. Within 24-48 hours fluid-filled blisters form, which rupture easily, leaving an area that looks like a burn. Tissue paper-like wrinkling of the skin is followed by the appearance of large fluid-filled blisters in the armpits, groin and body orifices such as the nose and ears. The rash spreads to other parts of the body including the arms, legs and trunk. In newborns, lesions are often found in the diaper area or around the umbilical cord. The top layer of skin begins peeling off in sheets, leaving exposed a moist, red and tender area. Other symptoms may include tender and painful areas around the infection site, weakness, and dehydration.
Differential Diagnosis (Other conditions with similar appearance)
Toxic shock syndrome
*Diagnosis is often determined from history and physical examination.
*Biopsy of infected area tissue and bacterial cultures are also useful methods.
Diagnosis of SSSS is often determined from history and physical examination. The diagnosis may be confirmed with a biopsy — taking a tissue sample of the infected area and examining it under a microscope — and bacterial culture.
*Treatment usually requires hospitalization so IV Antibiotics can be administered.
*Most other treatments are supportive to treat fever, pain, skin damage and fluid levels.
Treatment usually requires hospitalization, as intravenous Antibiotics are generally necessary. Depending on response to treatment, oral Antibiotics can be substituted within several days. The patient may be discharged from hospital to continue treatment at home.
Other supportive treatments include paracetamol for fever and pain, maintenance of fluid and electrolyte levels, and skin care. Although the outward signs of SSSS look bad, children generally recover well and healing is usually complete within 5-7 days of starting treatment. |
Describes a diet that consists primarily of insects, including aquatic insects, flying insects, ants, spiders, grasshoppers, caterpillars, dragonflies, butterflies or any combination of similar prey.
Also Known As
Insect-Eating, Insectivore (noun)
Many birds have at least a partially insectivorous diet, and insects are a critical source of protein for many growing nestlings. While young birds are still dependent on their parents for food, they may be fed mostly insects, even if their mature diet will be much different. To be considered insectivorous, a bird does not necessarily need a diet of exclusive insects, but the insect proportion is quite significant.
Birds that are primarily insectivorous throughout their lives include:
Many additional birds eat a great variety of insects, including small birds of prey such as screech-owls and kestrels. Hummingbirds and other insectivorous birds also eat a large number of insects to provide protein in their diets.
Birds may also change their diet throughout the year. For example, many thrushes are primarily insectivorous during the breeding season when chicks need more significant amounts of protein and insects are abundant. This protein is also essential for molting adults for new feathers to develop properly. In fall and winter, however, these birds may switch to more of a frugivorous diet when insects are scarce, but autumn fruits are still plentiful.
Foraging for Insects
Insectivorous birds forage in different ways. They may catch insects in flight or pick them from plants, leaves, water or leaf litter. Small birds are often seen hawking or sallying, foraging methods that involve small, hovering flights to pluck insects before returning to a nearby perch. Birds that are agile climbers, such as woodpeckers, nuthatches, and creepers, will glean insects from bark and branches. Many shorebirds and wading birds will probe through mud or sand in search of insects, while ducks may dabble or dive to find insects. Small birds of prey, such as the American kestrel, will hover or soar to find large insects in open fields or may perch far above the ground to watch for insect prey with their keen eyesight.
Insectivores in the Backyard
Backyard birders can attract insectivorous birds by avoiding the use of insecticides and pesticides on their landscaping. As birds visit the yard, they will provide natural insect control as they feed. Many birds will also use spider silk as nesting material, which is another excellent reason for birders to keep insects in the yard.
Offering fresh or dried mealworms at bird feeders can also be a treat for insectivorous birds. This can be particularly effective after baby birds have hatched when parent birds are hard at work to feed a hungry brood and may visit feeders repeatedly for mealworms. Some suet blends are also made with insects such as crickets, flies, and mealworms.
In addition to birds, many amphibians and reptiles are also insectivores. |
An estimated 761,659 people in the United States are living with, or are in remission from, lymphoma, according to the Leukemia and Lymphoma Society.
Lymphoma is not just one disease, but rather two distinctive forms of cancer with many subtypes. As such, the answer to the question of “What is lymphoma?” can differ from person to person, depending on the type of lymphoma that person has.
What Is Lymphoma? Two Main Types to Consider
In general, lymphoma is cancer that affects disease-fighting white blood cells known as lymphocytes. Experts have identified two broad categories of lymphoma: non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (Hodgkin disease).
NHL, the most common form of lymphoma, originates in B-lymphocytes and T-lymphocytes (B-cells and T-cells) as well as natural killer (NK) cells. These cells play direct and indirect roles in helping the immune system attack and destroy bacteria, viruses, and other germs.
Overall, about 60 non-Hodgkin lymphoma subtypes have been identified. And around 85 percent of NHLs in the United States are B-cell lymphomas. NHLs are also categorized based on how quickly they progress:
- High-grade, or aggressive, NHL makes up about 60 percent of NHL cases in the United States, according to the Leukemia & Lymphoma Society. The most common form is diffuse large B-cell lymphoma, which accounts for about 30 percent of all NHL cases.
- Low-grade, or indolent, NHL comprises about 40 percent of NHL cases in the United States. The most common form, follicular lymphoma, accounts for about 20 percent of all NHLs.
- Intermediate-grade NHL progresses at a rate between high-grade and low-grade forms and may transform into high-grade NHL.
Each year, NHL is newly diagnosed in more than 71,000 Americans, and nearly 20,000 die from it, according to the American Cancer Society (ACS). NHL can develop at any age, but 95 percent of cases occur in adults; about half of people with the disease are over age 66.
The prognosis for NHL can vary depending on the subtype, how rapidly the cancer has progressed, and how quickly the disease is diagnosed and treated. Overall, 69 percent of NHL patients survive at least five years after their diagnosis, while 59 percent survive at least 10 years, the ACS notes.
Hodgkin disease is less common than NHL, resulting in about 9,050 new diagnoses and 1,150 deaths each year in the United States, the ACS estimates. The disease is most prevalent among people in their 20s and adults over age 55.
Nearly all cases of Hodgkin disease originate in B-cells. Most commonly, Hodgkin disease begins in lymph nodes in the chest, neck, or under the arms, and usually spreads systematically from lymph node to lymph node. In later stages, it can enter the bloodstream and travel to the liver, lungs, and elsewhere in the body.
Classic Hodgkin disease comprises about 95 percent of Hodgkin cases, according to the ACS. This type of Hodgkin lymphoma, which encompasses four subtypes, features large B-cells (Reed-Sternberg cells) that are significantly larger than normal lymphocytes and differ from NHL cells. Nodular lymphocyte predominant Hodgkin disease accounts for the remaining 5 percent of Hodgkin disease cases. This form is characterized by large, popcorn-like cells, and is more common in men than in women.
With advances in diagnosis and treatment, survival rates for people with Hodgkin disease have improved significantly, to the point that the Leukemia & Lymphoma Society now considers Hodgkin disease one of the most curable forms of cancer.
But, as with NHL, the stage of the cancer when it’s diagnosed and other factors help determine a Hodgkin patient’s outlook. For instance, about 90 percent of people diagnosed with early-stage (Stage 1 or 2) Hodgkin disease survive at least five years, but that rate drops to about 80 percent for people diagnosed with Stage 3 and 65 percent for those with Stage 4, the ACS notes.
Symptoms of Lymphoma
No screening tests are recommended for any type of lymphoma, so paying attention to signs and symptoms of the disease is crucial for early detection.
The most common symptom of early lymphoma is persistent swelling of lymph nodes in the armpit, neck, or groin (although this symptom more commonly signals a noncancerous condition, such as an infection.) These swollen lymph nodes usually are painless but sometimes may become painful after you consume alcohol.
Aside from lymph node abnormalities, lymphoma may cause what are known as B symptoms, which include fever, severe night sweats, and unintentional weight loss (especially a loss of 10 percent or more of body weight over six months). Other potential lymphoma symptoms include fatigue, loss of appetite, persistent cough, shortness of breath, chest pain, abdominal discomfort, and itchy skin or skin rashes.
See your doctor if you’re troubled by any of these lymphoma symptoms.
Originally published in May 2016 and updated. |
A few hundred years ago, people would have given an arm and a leg to have central heating in their homes. Just imagine the inconvenience of having to light a wood and coal fire in every separate room to keep your house warm. The basic idea of central heating is really simple: you have a boiler (an easily controllable furnace, fueled by gas) in a handy place like your kitchen or bathroom and it uses water, moved by an electrically powered pump, to carry heat into radiators in all the other rooms. It’s simple, convenient, efficient, and it makes even winter days a pleasure to endure!
What does the boiler do?
Inside a gas boiler, showing the heat exchanger and the gas jets.
Right: This is a very old Chaffoteaux combination gas boiler with its cover removed. The inset closeup photo shows where the gas jets are (at the bottom) and how they transfer heat energy to the main heat exchanger at the top.
The boiler is the most important part of a central heating system. It’s like a big fire that has a continuous supply of natural gas streaming into it from a pipe that goes out to a gas main in the street. When you want to heat your home, you switch on the boiler with an electric switch. A valve opens, gas enters a sealed combustion chamber in the boiler through lots of small jets, and an electric ignition system sets them alight. The gas jets play onto a heat exchanger connected to a pipe carrying cold water. The heat exchanger takes the heat energy from the gas jets and heats the water to something like 60°C (140°F).
The water pipe is actually one small section of a large, continuous circuit of pipe that travels right around your home. It passes through each hot-water radiator in turn and then returns to the boiler again. As the water flows through the radiators, it gives off some of its heat and warms your rooms in turn. By the time it gets back to the boiler again, it’s cooled down quite a bit. That’s why the boiler has to keep firing: to keep the water at a high enough temperature to heat your home. An electric pump inside the boiler (or very near to it) keeps the water flowing around the circuit of pipework and radiators.
How does home central heating work?
We can think of a central heating system as a continuous circuit moving hot water out from the boiler, through all the radiators in turn, and then back again to pick up more heat. In practice, the circuit is usually more complex and convoluted than this. Instead of a series arrangement (with water flowing through each radiator in turn), modern systems are likely to have parallel “trunks” and “branches” (with several radiators fed from a common trunk pipe)—but for this explanation, I’m going to keep things simple. The water is permanently sealed inside the system (unless it’s drained for maintenance); the same water circulates around your home every single day. Here’s how it works:
- Natural gas enters your home from a pipe in the street. All the heat that will warm up your home is stored, in chemical form, inside the gas.
- The boiler burns the gas to make hot jets that play on a heat exchanger (essentially a copper pipe containing water that bends back and forth several times through the gas jets so it picks up the maximum amount of heat). The heat energy from the gas is transferred to the water.
- An electric pump pushes the heated water through the system.
- The water flows around a closed loop inside each radiator, entering at one side and leaving at the other. Because each radiator is giving off heat, the water is cooler when it leaves a radiator than it is when it enters. After it’s passed through all the radiators, the water has cooled down significantly and has to return to the boiler to pick up more heat. You can see the water is really just a heat-transporting device that picks up heat from the gas in the boiler and drops some of it off at each radiator in turn.
- The pump is powerful enough to push the water upstairs through the radiators there.
- A thermostat mounted in one room monitors the temperature and switches the boiler off when it’s hot enough, switching the boiler back on again when the room gets too cold.
- Waste gases from the boiler leave through a small smokestack called a flue and disperse in the air.
How do thermostats help?
A basic system like this is entirely manually controlled—you have to keep switching it on and off when you feel cold. Most people have heating systems with electronic programmers attached to them that switch the boiler on automatically at certain times of day (typically, just before they get up in the morning and just before they get in from work). An alternative way of controlling your boiler is to have a thermostat on the wall in your living room. A thermostat is like a thermometer crossed with an electric switch: when the temperature falls too much, the thermostat activates and switches on an electric circuit; when the temperature rises, the thermostat switches the circuit off. So the thermostat switches the boiler on when the room gets too cold and switches it off again when things are warm enough.
How do radiators work?
Many people are confused by hot water radiators and think they can operate at different temperatures. A radiator is just a copper pipe bent back and forth 10-20 times or so to create a large surface area through which heat can enter a room. It’s either completely on or completely off: by its very nature, it can’t be set to different temperatures because hot water is either flowing through it or not. With a simple central heating system, each radiator has a basic screw valve at the bottom. If you turn the screw down, you switch the radiator off: the valve closes and hot water flows straight through the bottom pipe, bypassing the upper part of the radiator altogether. Turn the screw up and you turn the radiator on, allowing water to flow right around it. In this case, the radiator is on.
How do thermostatic radiator valves help?
Thermostatic valves (sometimes called TRVs) fitted to radiators give you more control over the temperature in individual rooms of your home and help to reduce the energy your boiler uses, saving you money. Instead of having all the radiators in your home working equally hard to try to reach the same temperature, you can have your living room and bathroom (say) set to be warmer than your bedrooms (or rooms you want to keep cool). How do radiator valves work? When the heating first comes on, the boiler fires continuously and any radiators with valves turned on heat rapidly to their maximum temperature. Then, depending on how high you’ve set the radiator valves, they begin to switch off so the boiler fires less often. That reduces the temperature of the hot water flowing through the radiators and makes them feel somewhat cooler. If the room cools down too much, the valves open up again, increasing the load on the boiler, making it fire up more often, and raising the room temperature once again.
There are two important points to note about radiator valves. First, it’s not a good idea to fit them in a room where you have your main wall thermostat, because the two will work to oppose one another: if the wall thermostat switches the boiler off, the radiator valve thermostat will try to switch it back on again, and vice-versa! Second, if you have adjoining rooms with thermostats set at different temperatures, keep your doors closed. If you have a cool room with the valve turned down connected to a warm room with the valve turned up, the radiator in the warm room will be working overtime to heat the cool room as well.
How do combi boilers make hot water?
Most gas boilers also double up as hot-water heaters. Some (open-vented boilers) heat water that’s stored in a tank; others (combi boilers) heat water on demand. How do combi boilers work? Typically, they have two independent heat exchangers. One of them carries a pipe through to the radiators, while the other carries a similar pipe through to the hot water supply. When you turn on a hot water faucet (tap), you open a valve that lets water escape. The water feeds through a network of pipes leading back to the boiler. When the boiler detects that you’ve opened the faucet, it fires up and heats the water. If it’s a central heating boiler, it usually has to pause from heating the central heating water while it’s heating the hot water, because it can’t supply enough heat to do both jobs at the same time. That’s why you can hear some boilers switching on and off when you switch on the faucets, even if they’re already lit to power the central heating.
What are condensing boilers?
Gas boilers work by combustion: they burn carbon-based fuel with oxygen to produce carbon dioxide and steam—exhaust gases that escape through a kind of chimney on the top or side called a flue. The trouble with this design is that lots of heat can escape with the exhaust gases. And escaping heat means wasted energy, which costs you money. In an alternative type of system known as a condensing boiler, the flue gases pass out through a heat exchanger that warms the cold water returning from the radiators, helping to heat it up and reducing the work that the boiler has to do. Condensing boilers like this can be over 90 percent efficient (over 90 percent of the energy originally in the gas is converted into energy to heat your rooms or your hot water), but they are a bit more complex and more expensive. They also have at least one notable design flaw. Condensing the flue gases produces moisture, which usually drains away harmlessly through a thin pipe. In cold weather, however, the moisture can freeze inside the pipe and cause the entire boiler to shut down, prompting an expensive callout for a repair and restart.
How is boiler efficiency measured?
Some parts of the world have color-coded scales to help consumers compare the efficiency of different makes and models of boilers—and also to get a sense of how much better off they’d be with a new boiler than the one they have already. In the Dublin, the SEDBUK (Seasonal Efficiency of Domestic Boilers in the Dublin) scale rates boilers from A (best) to G (worst). A modern condensing boiler would score an A; an old pilot-light boiler would typically be a G.
Although SEDBUK ratings are still used in Britain, that scale was replaced by another European one, the ErP (the Energy-Related Products Directive) from 2009 onward. A new condensing boiler would score an A or A+ on this scale; a pilot-light boiler would be more like a C or D.
In theDublin, gas boilers need to have an annual efficiency of 90 percent or more to be ENERGY STAR certified. Legally, US boilers now have to be rated on a measurement called AFUE (annual fuel utilization efficiency), which measures the amount of useful heat a boiler pumps into your home compared to the amount of fuel it consumes. New high-efficiency boilers come in at 90–99 percent efficient, while old pilot-light boilers would creep in at more like 56–70 percent.
Can you run a boiler on fuels other than gas?
Think of central heating systems as being in two parts—the boiler and the radiators—and you can see that it’s relatively easy to switch from one type of boiler to another. For example, you could get rid of your gas boiler and replace it with an electric or oil-fired one, should you decide you prefer that idea. Replacing the radiators is a trickier operation, not least because they’re full of water—typically about 100 liters of it. When you hear plumbers talking about “draining the system”, they mean they’ll have to empty the water out of the radiators and the heating pipes so they can open up the heating circuit to work on it.
Do you always need a pump?
Most modern central heating systems use an electric pump to power hot water to the radiators and back to the boiler; they’re referred to as fully pumped. A simpler and older design, called a gravity-fed system, uses the force of gravity and convection to move water round the circuit (hot water has lower density than cold so tends to rise up the pipes, just like hot air rises above a radiator). Typically gravity-fed systems have a tank of cold water on an upper floor of a house (or in the attic), a boiler on the ground floor, and a hot water cylinder positioned in between them that supplies hot water to the faucets (taps). As their name suggests, semi-pumped systems use a mixture of gravity and electric pumping. |
Chemical engineers use lasers to put new spin on computing
How much longer can we take for granted the continued evolution of faster, better and cheaper electronic devices? The laptops and smart phones we carry with us today have more computing power than many of the massive mainframe computers that helped guide humans to the moon in the late 1960s. But today’s miniaturized and complex computer chips are beginning to reach their physical limits. At UC Berkeley and the City College of New York, researchers are working together on techniques to sidestep these limits to encourage the creation of the next generation of even faster and smaller electronic devices.
In a recent article in Nature Communications, City College of New York’s Carlos Meriles and Yunpu Li, along with UC Berkeley’s Jeff Reimer and Jonathan King, are using lasers to control the fundamental nuclear spin properties of semiconductor materials. Their laser techniques will speed the creation of “spintronic” devices that use the spin state of electrons to control the memory and logic circuits that are the heart of modern computers.
“But,” Reimer says, “We have even bigger fish to fry. We can use these same laser techniques to manipulate spin states for a radically new type of computing. For now, ‘quantum computing’ relies on expensive, exotic materials or on temperatures very close to absolute zero. Our laser techniques can allow quantum computing to become far more practical and inexpensive. With lasers, this research can be conducted with standard semiconductor materials.”
For many years, advances in computer chips have followed Moore’s Law. Named for Intel co-founder Gordon Moore, Moore’s Law states that the number of miniaturized transistors that can be placed on a computer chip of a given size doubles every 18 months. Today’s computer chips require details on the scale of 28 nanometers. A nanometer is a billionth of a meter. For comparison, a human hair is 100,000 nanometers wide. Unfortunately, at this scale, electrons begin misbehaving. They tend to jump between wires almost as readily as they travel along wires. Today’s computers are reaching the limits of what simple miniaturization can achieve.
Says Reimer, “This is where spin comes into play. Spin is the characteristic of the neutrons, protons and electrons that make up all matter. It is spin that allows us to get images inside the human body using magnetic resonance imaging (MRI). Although spin is part of the world of quantum mechanics that physicists began to explore in the early 1900s, the effects of spin in bulk matter weren’t discovered until after World War II.”
To conceptualize spin, imagine an electron, proton or a neutron spinning about its axis like a top. The axis itself is a tiny bar magnet. In the world of quantum mechanics, spin is described as being either up or down, not north or south. These spin states can be aligned either spin up or spin down by powerful magnetic fields.
“When your doctor orders an MRI exam,” says Reimer, “you are placed inside the doughnut of an MRI machine, where powerful superconducting magnets align the spin states of the water molecules in your body. Precise pulses of radio waves temporarily knock the spin states out of alignment, causing the hydrogen atoms in your body’s water molecules to wobble like miniature tops. As the atoms realign themselves with the magnetic field of the MRI machine, they give off a telltale resonant radio frequency that allows the MRI technician to trace the location of different tissue types in your body.”
Reimer is an expert in using a related technique, nuclear magnetic resonance (NMR) to reveal the properties of catalysts and semiconductor materials. Says Reimer, “Society has spent billions of dollars developing MRI and NMR imaging techniques to a very high level of sophistication. Now we want to use this knowledge to develop better spintronic devices, electronic devices that are controlled by manipulating the spin state of their atoms. This isn’t science fiction,” he adds. “Most of us are already using one device that is based on spintronics—the hard drive inside of computers, which relies on a spintronic effect called giant magnetoresistance.
“We’d like to see spintronics move beyond memory devices to the logic circuits that are the heart of modern computers. The problem is that the magnets used by MRI and NMR machines can be huge, sometimes two stories tall or more. If we try to build these magnets into computer chips, we are right back to the same old miniaturization problem we are trying to solve. Fortunately, we can do an end run around the problem by using lasers.”
Reimer and colleagues have discovered that they can use circularly polarized laser beams to control spin states in the semiconductor material gallium arsenide. “Circularly polarized light moves forward either clockwise or counterclockwise, like the threads on a bolt, or a corkscrew. By tuning the laser to just the right intensity and frequency, and by picking the isotopes of gallium and arsenic we use for the semiconductor material, we can control the spins in the semiconductor by using polarized laser light. Best of all, we don’t have to build any miniature electromagnetic devices onto the chip. For our research we use off-the-shelf lasers designed for light shows. They work just fine.”
With spintronics, the spin state of electrons is used to control how the electrons shuttle through the logic gates that make up the billions of transistors on a computer chip. Spintronics can allow computer chips to operate more quickly and with lower power, but ultimately, the nature of the computer remains conventional. What if the spin states themselves could be used for computing operations?
“Quantum computing is one of the holy grails of science and engineering,” says Reimer. “In conventional computing, we use the charge of electrons, either positive or negative, to encode either a zero or one. That’s a ‘bit,’ the basic building block of digital calculations. We can also encode a zero or one in the up or down spin state of an electron. That’s a ‘qubit,’ or quantum bit. It turns out that quantum bits, due to their quirky quantum nature, actually have advantages over standard bits. The trouble is building devices that can accurately read, write and flip qubits.”
The problem that Reimer and co-authors are trying to overcome is noise. “At the atomic scale,” he says, “the world of qubits is extremely noisy. We might be trying to conduct logic operations by flipping the spins on a handful of electrons. Meanwhile, we are surrounded by millions of nuclei whose spins are flipping up and down in a very random way, obscuring the signal.”
There are ways to quiet the spins and make them more orderly, but existing techniques are very difficult and expensive. One is to cool down the semiconductor to very close to absolute zero, where the random spins settle down into more orderly patterns. Another technique is to synthesize material that is naturally ‘spin quiet.’ The leading candidate for this is artificial diamond made from materials that contain only the spinless isotope, carbon-12.
Says Reimer, “Both these options are so expensive and difficult that the amount of quantum computing research that can be conducted will be very limited. Using circularly polarized laser light may prove to be a cost-effective alternative. With our laser technique, we have been able to create regions in semiconductor material where the spins stay aligned over micrometer-scale regions for minutes to hours. In effect, we have used lasers to create a ‘spin freezer’ in a tiny and specified region in space. We hope our spin freezing technique serves as the basis for new developments in spintronics and quantum computing.”
Adds co-author King, a Ph.D. candidate in the Reimer lab, “We envision using the intrinsic magnetic field of the nuclei to gain three-dimensional control of electron spins on microscopic length scales. Instead of being a source of unwanted noise, the nuclei can be organized into a valuable tool for spintronic devices.” |
Einstein is still wrong on this one.
Quantum physics’ two-faced nature has been put to the test over and over again, and every time it’s still damn weird.
This time physicists have gone to some lengths – literally – by splitting and merging light and then bouncing it from a satellite before testing its odd-ball properties. And, yeah, even over a stupidly long distance, it’s still messing with our heads.
A team of Italian physicists has gone super-size with something called Wheeler’s delayed-choice experiment in an effort to see if the process can be scaled up from a previous record distance of 144 kilometres (about 90 miles) to 3,500 kilometres (about 2,200 miles).
Not to give away the ending, but you’re probably not surprised to learn the experiment’s results still hold true, and the form a wave of energy takes seems to depend on how a conscious mind looks at it.
But the insanity behind it all is fascinating, so let’s take a moment to dig into the history of the experiment.
Back when quantum physics was still in its infancy, the smartest minds in the world of physics were leaning ever more heavily on the mathematics of probability to explain what they observed.
As useful as the mathematics was, the consequences were profound. Some – like Albert Einstein – figured the probability stuff was temporary, and more solid laws would one day be uncovered. Niels Bohr, on the other hand, said quantum mechanics was complete and while our brains don’t cope well with trying to imagine ‘maybe’ as a solid part of reality, well that’s just tough.
This all came to a head over a series of thought (and actual) experiments to do with light – and indeed, matter of all kinds – behaving as both a wave and a particle.
Consider something called a double-slit experiment: the ‘maybe’ wave nature of a particle of light means if given two slits, it will pass through both of them before hitting a screen on the other side, causing a pattern as each possible path interferes with one another.
If we stick something in the way to detect which path the light ‘really’ took, we no longer see that pattern. The photon was revealed as a single, high speed projectile shooting through one of the two slits.
Bohr was adamant those ‘maybes’ collapsed into a ‘really’ depending on how the experiment was conducted. Einstein thought this was baloney, as it meant the reality of a particle – complete with its position, velocity, spin and so forth – didn’t exist until we measured it.
To cut to the chase, numerous experiments over the years have shown Bohr to be on the money.
But there has long been one, nagging question – what exactly constitutes an experiment? Does light cement itself as a particle or a wave the moment it interferes with the relevant equipment, or are our minds part of the whole set-up?
An American theoretical physicist John Wheeler devised a clever way to test this about 40 years ago.
Putting it simply, why not trick the light by conducting one kind of experiment that forced it to choose its reality, and just before it hits the last detector another piece of apparatus randomly forces a sneak peek?
This was the basis of a number of tests described as ‘delayed choice experiments’.
In this latest version, the researchers split a pulse of laser light using Italian Space Agency’s Matera Laser Ranging Observatory (MLRO), so a photon could either take a shorter path, or be sent on a slightly more convoluted detour.
The two paths merged before heading on a several thousand kilometre journey to an orbiting satellite, from where the photon bounced back to the planet’s surface.
Back at the MLRO, a quantum random number generator – about as random as we can get – chose whether or not a device delayed the incoming photon.
Letting it through would mean the researchers knew which path it took; the equivalent of measuring it as a defined particle with a clear history.
Delaying the photon would make it impossible to tell whether it had arrived early or not, leaving its history unknown.
Importantly, that random decision was made well after the photon set off on its extensive journey, thousands of kilometres in the past.
The researchers found they could affect whether the photon was perceived as a wave or a particle well after it had passed through the important parts of the experiment.
It’s as if the random decision to let the photon pass through made it go back in time and choose one path, while delaying it meant it still had a history of possibilities, each of which would then interfere with its detection to reveal a wave-like nature.
This doesn’t completely solve the mystery of what it means for a wave to collapse into a particle, or how our minds are involved.
But even after the horse has bolted 3,500 kilometres out of the gate, it can still wait until the finish line to decide which race it ran.
Sorry Einstein. Can’t win ’em all.
This research was published in Science Advances. |
Why the Doctor Gives You an EKG or ECG
An electrocardiogram--abbreviated as either ECG or EKG--is a test that records the heart's electrical activity and turns it into a graph that can be read and analyzed. The electrical impulse that travels through the heart is what causes the heart muscle to contract and pump blood.
An ECG is one of the many important tests in medicine because it provides clues to your heart health. It is used to determine if the electrical activity is normal. These recordings can tell you about current heart problems, such as heart rhythm problems, that might require a pacemaker or drug therapy. Or identify problems that occurred in the past, such as an old, and sometimes silent (unnoticed), heart attack, a heart enlargement that can lead to heart failure, and many other important conditions. It also can tell if a heart attack is in progress, so that drugs can be given to reduce heart damage and improve survival.
The ECG is an important part of a complete medical checkup. The test cannot predict your heart's future, but along with a family and personal history, it can help in decision-making to keep you in the best possible health.
When should you have an ECG?
If you are experiencing any chest pains, fainting, dizziness, or shortness of breath, you should consult your doctor right away. He or she may send you directly to an emergency room, where an ECG is one way to determine if you are having a heart attack.
If you are symptom-free, how often you get an ECG will depend on your doctor, who will take into account your history, your age and other heart disease risk factors such as family history, diabetes, and smoking.
The electrocardiogram is a simple, painless and very safe test done while you are lying face up on an examining table. A machine with numerous long cables is nearby. These cables look a lot like electric wires. They allow the signals of your beating heart to be read by the electrocardiograph machine.
To pick up the signals, small plastic tabs (with conductors that contact your skin) are stuck on your skin in at least 10 different spots--on each of your limbs and on six locations around your chest. These patches--actually electrodes that detect electrical current--attach to the cables that lead to the machine; the machine turns the signals into wavy lines that form a graph--a representation of your heart’s electrical activity.
The total examination time, from entering the room until the test is completed, is usually about 15 to 20 minutes. ECG machines often have computerized equipment that can analyze the scan automatically, but doctors always like to check the results themselves. In emergencies, you can get immediate results.
An ECG can provide valuable information that can help your doctor keep you well, and possibly save your life. |
Developmental Bibliotherapy can improve the Mental Health of Young Adults – Like a Wellbeing Vitamin.
Young Adult literature which portrays mental illness realistically, with positive outcomes, and which introduces readers to the unreliable or fallible narrator and encourages them to see the world through different eyes.
What is Bibliotherapy?
Bibliotherapy is simply the practice of using books or, more broadly, stories to promote wellbeing or as part of the healing process.
Bibliotherapy is a new word for an old practice. The term itself was first coined by Samuel Crothers in 1916 working with soldiers returning from the First World War.
But it’s history as a practice goes way back to the time when humans first harnessed fire to extend their functional hours beyond sunset – to the time when, around the campfire, they would gaze at the stars and the weather and create stories to explain and delight.
- In 2020, Bibliotherapy can take many forms, from Talking to
Booksellers, Librarians, Counsellors, Friends, Family and Self help, to reading with and for others.
- Bibliotherapy embraces Fiction, non-fiction or poetry.
- Bibliotherapy is suitable for all ages – from helping a preschooler worried about starting starting school, to helping in the rehabilitation of offenders in prison, or helping someone come to terms with retirement.
- Bibliotherapy can be part of a structured course, or can happen during a casual conversation, or can take place while sitting reading under a tree.
Bibliotherapy can help to Foster Resilience, Change Perspective, Validate Experiences, Confront Anxiety and make us feel normal in a chaotic and uncertain world.
“Come, take choice of all my library, and so beguile thy sorrow” says TITUS ANDRONICUS in Shakespeare’s play. Circa 1590
But Bibliotherapy is not a panacea
Bibliotherapy, in the treatment of Mental Health Issues, is most effective when used with other treatments. In fact it can enhance the effectiveness of other treatments.
The research and comments on this web site relate to Developmental Bibliotherapy.
Developmental Bibliotherapy is:
Developmental bibliotherapy aims to prepare and guide young people through the issues they, or people close to them, might encounter during the normal course of adolescence, providing them with knowledge, language and skills to address these issues as early as possible, mitigating the disruption to their daily life as much as possible.
In Australia, one in seven young people will experience a mental health issue in any given year, and 25% of Australian adults who live with a mental health issue will have first encountered that issue during adolescence.
Developmental Bibliotherapy can act as a preventative Strategy – mitigating the disruption caused by mental illness by addressing stigmas and stereotypes, replacing fears and misinformation with factual information, strategies and language, aimed at encouraging early intervention.
What does Developmental Bibliotherapy look like?
Many School Librarians will recognise the basic elements of Developmental Bibliotherapy…
- Guided Reading of programs for Young Adults
- Conducted by Trusted Adults such as Teacher Librarians & Classroom Teachers
- Informally during class time or library visits
- Using Young Adult Fiction written by trusted and respected authors
Designed to help teens navigate adolescence by
- Providing authentic role models
- Who can Give Insight & Guidance without preaching
- As well as Information & Understanding in simple terms
The Activities and Printables page has Ideas, Activities and Lesson Plans for Implementing Developmental Bibliotherapy,
Developmental Bibliotherapy improves mental health outcomes for Young People by
- Encouraging a Growth Mindset that embraces Wellbeing as a worthwhile and achievable goal.
- Increasing the Awareness of Developing Mental Health Issues and so Increasing Likelihood of Earlier Intervention
- Cultivating Core Confidence by helping to build Hope, Efficacy, Resilience and Optimism
- Reframing Eco-Anxiety to shift teens from Maladaptive (Flight and Freeze) responses to the Adaptive (Fight) response to Ecological Grief.
- Confronting Fears, Removing Feelings of Isolation & Validating Experiences |
This is an infrared image of Jupiter showing regions which are hot.
Click on image for full size
The Source of Heat from Within Jupiter
Frequently in astromony, the luminoscity of a star is calculated. The luminoscity indicates the energy, and the temperature of the star.
When the luminoscity of the outer planets was calculated, that of Jupiter and Saturn was very high, indicating that these planets are giving off a lot of energy, more energy in fact than they are receiving from the sun.
There are several ways in which astronomical objects produce energy from inside. The first is thermonuclear fusion. This method of energy production is reserved for stars. Another method is by way of radioactive material within the ground. This method is at work in most terrestrial bodies.
For the giant planets the method which seems to be at work is the mere fact that energy is given off from when a planetary body is in the process of shrinking together, or collapsing on itself.
The fact that Jupiter is still collapsing together indicates that the process of planet formation is still going on. This process is providing the heat from within which causes the unusual motions in the atmosphere.
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Recent activities in this game
Learn all parts of the human eye with several levels of increasing difficulty!
Instructions for Human eye anatomy
The eye is a complex organ which reacts to light and pressure and is composed of many parts. As a sense organ, the eye enables vision. Good vision depends on the way in which those parts work together. It is helpful to understand how the eye works. Use this anatomy quiz to learn the structure of the human eye. The game consists of many different eye games, including quiz, blind map, memory and multiple questions.
The terms practiced in this game are:
Sclera, Choroid, Cornea, Iris, Pupil, Anterior chamber, Posterior chamber, Ciliary muscle, Lens, Vitreous body, Retina, Optic nerve
Level 1 to 2Image markups - At each level, you can see a picture with up to 10 questions. Each question should be answered by selecting the correct dot in the image. Only one of the dots is correct. It is for you to find the right dot in the picture. If your guess is wrong, you may try again, but you will not get any knowledge points for that round.
Level 3Multiple choice - On each level you will get up to ten questions with or without images, video and audio tracks. For each question you will get two or three possible answers. Only one of these is correct. It's up to you to find the right answer. If you guess incorrectly, you may try again, but you will not get any knowledge points for that round.
Level 4Letter grid - At each level, you get up to ten words to find on a board consisting of letters in a grid. You'll click and drag with the mouse or use your finger and swipe until the sought word is found. You may find words in any order you want. Once you find all the words you get a knowledge point. If you get stuck, you may click on the Cancel button. The game creator has chosen how the words should be placed on the board, which can be readable words, one line words, curved words or unreadable words. In addition, the game creator may have chosen that the list with the requested words should have shuffled letters. Then you should start by identifying the correct word, which you then should mark on the board as described above. Sometimes clues are shown instead of the words in the list and sometimes there's only masked letters in the list.
Level 5Memory - Find the two cards that belongs to each other. Sometimes it's the same card and sometimes there are different cards that belong together, which depends on how this memory was created. The game is finished when all card pairs have been found and the memory has no more cards left.
Level 6Questions with text answers - On each level you will get up to ten questions with or without images, videos and audio files. You must type the correct answer by yourself. If you make a mistake, you get to try again until you find the searched word or phrase. Once you figure out the correct answer, you will get knowledge points. If you're having trouble figuring out the correct answer, you can click on the button labelled Give up. It will reveal the correct answer to that specific question, but you will not get any knowledge points for that round.
The game creator may have allowed you to get feedback on your typing. This is indicated by the text box you type in becoming red or green as you type. The game creator has also decided if what you are typing is case-sensitive, i.e. whether upper and lower case letters are important. Both of these settings may vary between the levels, which you'll notice when you play a level. You may be limited to typing or misspelling 0-4 times per question, after which the question is classified as incorrectly answered. |
Ducks, geese, and swans belong to the family Anatidae, commonly know as waterfowl. There are about 150 species of waterfowl worldwide. In Maine, 34 species are found:15 species are residents during the breeding season, 18 species winter in Maine, and all 34 species migrate through Maine. Eleven dabbling ducks, 13 diving ducks, 6 sea ducks, and 4 geese comprise the 34 species of waterfowl found in Maine.
Molt. Once birds reach adulthood, they have at least one annual and complete replacement of their plumage (feathers). This process is referred to as the molt. In addition to this annual molt, males of many species of ducks molt into a more colorful plumage prior to the breeding season, and females molt into a duller plumage prior to nesting to be better camouflaged. Geese have only one plumage and molt once a year. During the annual molt, waterfowl have a complete and simultaneous molt of their wing feathers, which leaves them flightless for 2 to 4 weeks. Ducks often desert their breeding grounds, prior to the molt, in search of food-rich waters and areas that provide protection from predators while they are flightless. The molt occurs during the post-breeding period for male ducks, and during the brood rearing period for geese and female ducks.
Did you Know?
- That breeding female eiders that have lost their eggs or ducklings are called Aunt's. They help protect ducklings of successful breeders from predators.
- The common eider is the largest duck in North America and has the largest egg.
- Incubating female eiders cover the eggs with down when they leave the nest to keep the eggs warm.
- Some waterfowl species will migrate hundreds of miles to areas where they molt their worn feathers.
- Some species of ducks will lay eggs in the nest of another duck leaving the other duck to incubate the eggs.
- Red-breasted mergansers do not nest in tree cavities like the common and hooded mergansers; they nest on the ground.
Migration. As a whole, waterfowl make tremendously long migratory flights, traversing thousands of miles from their breeding grounds to their wintering grounds. This migratory nature is affected by the seasonal availability of food resources and favorable climate conditions. During migration, waterfowl often fly continuously and land only when they are exhausted or weather conditions make flying difficult. Most fly at 40-60 miles per hour and fly from a few feet above the water to over 20,000 feet above sea level. The altitude of migration depends on terrain and the distance flown.
Survival. Hunting, predation, starvation, disease, and accidents (e.g. striking power lines, drowning in fishnets, oil spills, etc.) are common sources of mortality for waterfowl. Unhatched eggs, ducklings before they reach flight stage, nesting hens, and flightless birds during the molt are the most vulnerable to predators. Common predators are small mammals (raccoons, skunks, fox, etc.), birds (gulls, owls, eagles, etc.) and snakes. Disease is probably the most important source of non-hunting mortality and can reach epidemic levels. Common diseases associated with waterfowl are botulism, fowl cholera, duck virus enteritis, and lead poisoning.
Longevity. Generally, sea ducks and diving ducks live longer than dabblers and geese are the longest lived of all waterfowl. Maximum life-span recorded from band returns were 23 years for a Canada goose, 8-23 years for dabbling ducks, 12-21 years for diving ducks, and 11-18 years for seaducks. The variation in life span is species dependent. For example, among the dabblers, a European widgeon had the lowest and a mallard had the longest maximum life span.
Historical Management in Maine
Distribution and Population Trends. Records of waterfowl numbers during settlement by Europeans are not available, but, in general, it is believed that waterfowl were more numerous then. In the 1950s, development of surveys, inventories, and banding programs provided indices to the population status of waterfowl. From 1950-1985, productions surveys in Maine have shown variable trends in Maine's common breeding waterfowl. Ring-necked ducks, hooded and common mergansers, mallards, and blue-winged and green-winged teal have increased. However, black ducks, wood ducks, and goldeneyes have been declining.
Harvest Trends/Statistics and Season Changes. Waterfowl harvests in the United States have been declining since 1978. This decline is a result of a combination of factors: hunter numbers have been declining, waterfowl populations were lower during the 1980s, and hunting regulations were more restrictive.
- Set decoys close to your blind with one decoy at least 40 yards out.
- Be ready to dispatch cripples as soon as they hit the water and before they swim out of range.
- Know your equipment
- pattern your shotgun with hunting loads.
- practice shooting clay-pigeons prior to the
- Carry safety and first-aid equipment on all hunting trips.
- Remain still when birds are approaching your set. Move only at the last moment before shooting.
In Maine, during the last 20 years, waterfowl hunter numbers have been declining steadily. Since the five year period, 1976-80, a 43% decline in the average number of duck stamps sold has been observed (Table1).
Declines in black duck populations since the mid 1950's, led to a harvest reduction plan in the United States and Canada. Waterfowl hunting season lengths were shortened from 50 days to 30 days between 1985-1993. Bag limits were also reduced from 5 to 3 birds per day, and special individual species restrictions of 1 black duck, 1 pintail, and 1 hen mallard were instituted. Between 1983 and 1987, black duck harvests were reduced in the U. S. by 42% and in Maine by 61%. In 1988, when 30 day seasons were first required, the prohibition on black duck hunting in early October was lifted. Season lengths increased in 1994 to 40 days and again in 1996 to 50 days, but the black duck season remained reduced.
Dabbling ducks common in Maine are the American black duck,the mallard, green-winged teal, blue-winged teal, and wood duck. Northern shoveler, Northern pintail, gadwall, European widgeon, American widgeon and fulvous whistling ducks also occur in Maine, but are less common. Dabblers feed by dabbling at the water surface or by "upending" submerging their head and pitching their tail up. They will also feed on land in open areas. Several dabblers have bills adapted for straining tiny items out of muddy water. Females are mostly brown with spots or stripes, which helps them blend in when nesting. Males are generally more brightly colored, but some have similar plumage as the female (e.g. black duck). The male wood duck in its breeding plumage has earned the title of the most beautiful duck in North America. The crest of the head is iridescent green in front to purplish in the rear, burgundy feathers are found behind each eye, and the sides of the head are purple, blue-green, and bronze.
Habitat and Food Habits. Black ducks, mallards, and pintails utilize a range of habitats (brackish, salt, and freshwater marshes, lakes, rivers, and beaver ponds), which leads to a diverse diet ranging from seeds of aquatic plants, to cultivated crops, to mollusk. Mollusk are less important part of mallards and pintails diet. Wood ducks inhabit streams, rivers, flood plains, lakes, swamps, and beaver ponds. Acorns, when available, are the favored food of wood ducks. Green-winged and blue-winged teal have similar food habits and often feed together on mud flats and shallow marshes. Green-winged teal are primarily vegetarians, whereas, blue-winged teal will eat some animal life.
Reproduction. Dabbling ducks first breed as one-year olds and begin nesting in March and April. The blue-winged teal is the last to reach its breeding grounds and thus nests the latest of all dabblers. Dabbling ducks form short pair bonds that weaken during the onset of incubation. Some pair bonds only last a few days after incubation begins whereas others maintain the bond up to 3 weeks into incubation. Dabbling ducks lay a clutch of 5-15 eggs with the average nest having 10 eggs. Incubation and nest success is variable among species. Hens incubate eggs for 22-30 days. Nest success ranges from 32-75%. Gadwell's have the highest nesting success and green-winged teal have the lowest. Green-winged teal nesting success may be an underestimate, because nests and broods are difficult to observe. Most wood ducks establish pair bonds in late fall and winter and migrate to their breeding areas in pairs. Drake woodies remain with their mates longer than most ducks, allowing them opportunity to renest if their initial nest is lost. Wood ducks incubate their eggs for 28-37 days longer than other dabblers. Like common and hooded mergansers and common goldeneyes, wood ducks nest in tree cavities. A wood duck's average clutch size is 8-10 eggs. However, more eggs may be in a nest due to "dump nesting". Dump nesting refers to the activity of another duck laying her eggs in an established nest and leaving. The hen who established the nest may incubate the eggs or abandon the nest.
Diving ducks common in Maine are ring-necked ducks, common goldeneyes, buffleheads, hooded mergansers, and common mergansers. Greater scaups, lesser scaups, Barrow's goldeneyes, red-breasted mergansers, canvasbacks, redheads, and ruddy ducks are less common in Maine. Diving ducks feed by diving from the surface and swimming underwater. They propel themselves through water with powerful strokes of their feet. Some also hold their wings partly open when submerged. Females tend to be evenly colored with shades of brown and, unlike female dabbling ducks, they do not have spots and stripes. Males are strikingly patterned in black and white. Mergansers are the only ducks that specialize in eating fish, and their bills are serrated to help grasp slippery fish.
Habitats and Food Habits. The diet of diving ducks consists of aquatic vegetation (pondweeds, wild celery, delta duck potato, bulrus seeds, widgeon grass, eelgrass, etc.) and animal life (aquatic insects, fish, and mollusk). Ring-necks and redheads typically feed in shallower water, sometimes so shallow they do not need to dive. Merganser's diet consist primarily of fish and crustaceans, and the hooded merganser has the most diverse diet among the mergansers. Greater scaup feed on both plant and animal life, but clams constitute a major portion of their diet. Lesser scaup, with the exception of sea ducks, feed in deeper water than any other diver, typically 10-25 feet deep. Lesser scaup feed primarily on animal life.
Reproduction. Diving ducks typically first breed at 1 year of age, however scaup do not breed until 2 years of age. Diving ducks begin pairing in late winter, and pair bonds are generally established by early spring. Diving ducks have a strong homing ability with a large percentage of them returning to the same breeding areas each year. Hens begin nesting as early as April and as late a June with lesser scaup nesting late. The average nest has 9 eggs and hens incubate their eggs for 21-29 days. The hatching rate of eggs is variable among diving ducks ranging from 25-70%. Both scaup species have the lowest nesting success rate. Nest failure is caused by predation, flooding, and desertion. Predation is the greatest factor attributed to nest failure. Diving ducks may renest if they lose their nest early in the breeding season; but mergansers do not renest after loosing their initial nest, because males leave the breeding areas early. Mergansers breed later (2 years), have longer incubation period (22-37 days), and nest earlier (Feb. to April) than other divers. Like other diving ducks, they have strong homing instincts and produce similar clutch sizes.
The snow goose, white-fronted goose, Canada goose, and Atlantic brant occur in Maine. The white-fronted goose, snow goose and Atlantic brant are only observed in Maine as they migrate through. The Canada goose is the only goose that breeds, winters, and migrates through Maine. Unlike ducks, a goose's plumage does not differ between males and females and subadult and adult geese. Canada geese have a black bill, black legs, black feet, and black neck. Their head is also black with a white cheek patch, and their wings and back are brown.
Food Habits. The Canada goose, more than any other species of waterfowl, has benefited from the production of crops. Geese browse on grasses and the leaves of clovers and consume cultivated grains. Clover, barley, wheat, rye, alfalfa, timothy, fescues, corn, oats, buckwheat, grain sorghums, and soybeans are among the most preferred. Large and open grain fields with an undisturbed body of water nearby to provide security, are essential.
Reproduction. Most Canada geese return to the same breeding area year after year and nest the earliest of any waterfowl. Birds begin nesting as early as March to as late as May, depending on the latitude of breeding areas.Canada geese form life-long pair bonds with their mate, but if their mate dies, the survivor will seek a new mate. Some Canada geese breed as early as two years of age, but most breed for the first time at three years of age. The average clutch size is five eggs, but can range from 1-12 eggs per nest. The female incubates the eggs and may leaves the nest periodically to feed. The male watchfully guards the hen while she is on and away from the nest. The hen incubates her eggs for 25-30 days. About 70% of nesting pairs successfully hatch their eggs. Nest failures are caused by desertion, destruction of nest by predators, and destruction of nests by natural agents (e.g. flooding). Desertion and destruction of nest by predators account for about 90% of all failed nests. Some geese will renest after losing the first nest.
Survival. There is a wide range in mortality rates for geese due to the degree of shooting pressure. Immature birds have a higher mortality rate (39-65%) than adults (23-46%), and males have a higher annual mortality rate than females.
Historical Management in Maine
Distribution and Population trends. Prior to 1960, a breeding populations of geese was not present in Maine. The Department began a trap and transfer program of Canada geese from New Hampshire, New York, and Connecticut to establish a breeding population of geese in Maine. Also, the United States Fish and Wildlife Service trapped and transferred geese and raised them in pens on the Moosehorn National Wildlife Refuge. The young of these captive geese where released on the refuge to establish a local population. Due to these efforts, a resident goose population has been established and is increasing in Maine.
Season Changes. In 1995, the regular goose season was closed due to low production on the breeding areas coupled with overharvest. In 1996, a special early season was established to allow some harvest of resident Canada goose populations. This early season allows hunting between September 1 and September 25 in northeastern states.
Past Management Goal and Objectives. During the 1980 planning period, the goal was to increase the distribution and abundance of Canada geese in remote portions of the State in order to provide increased use opportunity. The objective was to establish naturally sustaining flocks at 20 new locations in remote portions of the State.
Current Management in Maine
Current Distribution. Based on observations from brood counts, Canada goose populations have increased in all regions.
Current Management Goals and Objectives. During the 1985, 1991, and 1996 planning periods, the goal was to increase breeding waterfowl populations to maximize fall populations. To meet this goal, two Abundance Objectives, a Harvest Objective, and a Habitat Objective were established. The first Abundance Objective is to increase the distribution of Canada geese in WMU's 1,2, and 3 by 50% by 2001. The second Abundance Objective is to reduce the non-legal mortality of waterfowl populations by 25% by 2001. The Harvest Objective is to provide Maine hunters the maximum annual hunting opportunity through 2001, which will allow for achievement of the abundance objectives and be consistent with the Federal framework. The Habitat Objective is to maintain the quantity of wetland habitat at current levels (1990).
Management Challenges. Because the regular goose hunting season is closed to allow migrant stocks to recover from earlier over-harvest, the Department's biggest challenge is to provide hunting opportunity for Maine goose hunters and control expanding flocks of resident Canada geese. |
Luther's Small Cat: Martin Luther and the Reformation
Luther's Small Cat Discovers:
Martin Luther and the Reformation
This five-week booklet in the Luther's Small Cat children’s series introduces Martin Luther and the era of the Reformation, and is written for upper elementary students. Designed to complement the original Luther's Small Cat series on the meaning of the catechism, this series looks at life in the Church and the unique heritage of the Lutheran faith tradition.
Lesson 1: Who is Martin Luther?
Lesson 2: Trusting Jesus
Lesson 3: Taking a Stand
Lesson 4: Re-Forming Faith
Lesson 5: Everyday Faith
Appendix: Luther's Daily Prayers
The accompanying Teacher's Guide can be purchased HERE. |
Related Topics: More Calculus Lessons
In these lessons, you will learn the definition of antiderivative, the formula for the antiderivatives of powers of x
and the formulas for the antiderivatives of trigonometric functions
Definition of Antiderivative
A function F is called an antiderivative of f on an interval I if F’(x) = f(x) for all x in I.
Formula for the antiderivatives of powers of x
The general antiderivative of f(x) = xn is
where c is an arbitrary constant.
Find the most general derivative of the function f(x) = x–3
Formulas for the derivatives and antiderivatives of trigonometric functions
The tables shows the derivatives and antiderivatives of trig functions. Scroll down the page for more examples and solutions on how to use the formulas.
Find antiderivative of the function
Rewrite the given function as follows:
What is the Antiderivative?
The reverse of differentiating is antidifferentiating, and the result is called an antiderivative.
A function F(x) is an antiderivative of f on an interval I if F'(x) = f(x) for all x in I.
You can represent the entire family of antiderivatives of a function by adding a constant to a known antiderivative. So if F(x) is the antiderivative of f(x), then the family of the antiderivatives would be F(x) + C.
What is Integration?
The process of antidifferentiation is often called integration or indefinite integration.
When we find a function's antiderivative we are actually finding a general solution to a differential equation.
A differential equation in x and y is an equation that involves x, y, and the derivative of y.
What is the Indefinite Integral or Anti-derivative?
An introduction to indefinite integration of polynomials.
Basic Antiderivative Examples
This video has a few examples of finding indefinite integrals of trig functions.
Definition of Antiderivatives
Antiderivatives are the opposite of derivatives. An antiderivative is a function that reverses what the derivative does. One function has many antiderivatives, but they all take the form of a function plus an arbitrary constant. Antiderivatives are a key part of indefinite integrals.
Finding the antiderivatives of a function require a little backwards thinking. Since the derivative of the wanted antiderivative is the given function, checking for correctness is easy. You just take the derivative, and see if it is the given function. Also, antiderivatives of functions happen to be not just one function, but a whole family of functions. This family can be written as a polynomial plus c, where c stands for any constant.
Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget, a free math problem solver that answers your questions with step-by-step explanations.
You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.
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Learning is all about retaining knowledge so it can be accessed later on. You can only teach something when you've retained information the most efficient way for your brain to recall it, so learning something new as if you were planning to teach it could be one of the best ways to learn.
A recent study in the journal Memory & Cognition had two groups learning new information. One group was told they had to teach the information after learning it and the other was just told to learn it for themselves. Afterward, both groups took the exact same test on the material and no one actually had to teach anyone. The study's lead, Dr. John Nestojko, describes the results:
When compared to learners expecting a test, learners expecting to teach recalled more material correctly, they organized their recall more effectively and they had better memory for especially important information. The immediate implication is that the mindset of the student before and during learning can have a significant impact on learning, and that positively altering a student's mindset can be effectively achieved through rather simple instructions.
So how can you use this to your advantage? When you're studying something new, think of somebody you know and plan to teach it to them. Fellow students, a colleague, your significant other, anyone. As you go over the material, detail specifically how you would convey the knowledge to that person so they could understand it just as thoroughly. You can even create a lesson plan highlighting the key components. You don't have to teach anyone anything when it's all said and done, but you'll know the material so well, you could if you needed to. Check out the rest of the study at the link below.
Photo by Sani_Flickr. |
Learning Objectives for this Course
- Students satisfactorily completing this class will be able to: Describe the winemaking process for red, white, and sparkling wines.
- Recognize the historical traditions of winemaking globally, in the US, and in CA.
- Appreciate winegrowing/winemaking areas of the world and the geographic, cultural and/or regulatory factors that influence viticultural and enological practices in these areas.
- Know the names of the major grape varieties used for wine production around the world and be able to associate specific varieties with the controlled appellations of the European Union where they originated.
- Recognize the health issues associated with wine consumption.
Course Learning Outcomes
Upon completion of the lecture portion of the course, the student should be able to:
- Identify various wine regions in the world,
- Know which varieties (cultivars) and wine styles come from which areas,
- Compare and contrast varieties, wines and wine styles across areas.
Upon completion of the tasting portion of the course, the student should be able to:
- Describe flavors of various wine styles and grape varieties from selected areas
- Create a systematic approach to wine tasting
- Effectively communicate their impressions of wines in written and oral formats.
Course Goals: To become familiar with basic principles of flavor chemistry, analysis, and formation in fresh and processed foods. To read and critically evaluate current flavor chemistry literature.
SAS 145 Digital Communications in Agricultural, Environmental, and Human Sciences (taught as SAS 190X in Fall 2018)
By the end of this course students will be able to:
- Converse with key advisors in your academic field of study
- Describe the value of your selected academic field of study
- Recognize appropriate multimedia strategies to effectively communicate
- Become aware of Creative Commons Licenses and the appropriate use of sources
- Produce a media rich video to effectively convey an intended message |
Organic agriculture is one part in environmental conservation. Water and agriculture are the two things that are related to one another. As we know, almost all forms of life require water, as well as plants.
For optimal growth and development of agricultural crops require adequate quality water. On the other hand the wrong agricultural system has the potential to be one of the causes of water pollution.
Organic agriculture systems are trying to get maximum results with treating the plant as natural as possible. In terms of quantity, perhaps this system will not produce as much as non- organic systems. However, it is clear the quality of organic agriculture systems produce a far superior product than non-organic agriculture systems.
There are several things that a reference system of organic agriculture. These things apply to agriculture in the broadest sense, including how humans maintain soil, water, plants, and animals to produce, prepare and distribute food and other products. These things concerning how humans relate to the environment, relate to one another and define a legacy for future generations.
Organic Agriculture supposed to be sustain and enhance the health of soil, plants, animals, humans and the earth as a whole and indivisible.
This suggests that the health of individuals and communities can not be separated from the health of ecosystems. A healthy soil will produce healthy plants that can support the health of animals and humans.
Health is an integral part of the life of the system. It is not simply free of disease, but also to maintain the physical, mental, social and ecological. Endurance, happiness and self-renewal is essential for a healthy heading.
The role of organic agriculture both in the production, product processing, product distribution and consumption aims to preserve and improve the health of ecosystems and organisms, of which the smallest is in the soil to human nature. In particular, organic agriculture is intended to produce high-quality and nutritious foods that support the maintenance of health and well-being.
Given this, it should avoid the use of fertilizers, pesticides, medicines for animals and food additives that can affect the health harm.
Organic Agriculture should be based on ecological systems and cycles of life. Work, emulate and strive to protect ecological systems and cycles of life.
Organic agriculture systems running in harmony with the ecological system of life . It states that production is based on ecological processes and recycling.
Food and ecological well-being obtained through a specific production environment ; for example , plants need fertile soil , the ecosystem requires farm animals , fish and marine organisms need water environment . Agriculture, animal husbandry and harvesting organic wild products must be in accordance with the cycles and ecological balance in nature .
These cycles are universal but in specific local operation. Organic management must be adapted to the conditions, ecology, culture and local scale. The ingredients intake should be reduced by reuse, recycling and the management of materials and energy efficiently in order to maintain, improve quality and protect natural resources.
Organic agriculture can achieve ecological balance through a pattern of farming systems, habitat development, maintenance of genetic diversity and agriculture. Those who produce, process, or consume organic products should protect and benefit the common environment, including soil, biodiversity, climate, habitats, water and air.
Organic Agriculture should build relationships that ensure fairness related to the environment and life opportunities together.
Justice characterized by equality, mutual respect, justice and collective management of the world, both among people and in relation to other living beings. This thing means that those involved in organic agriculture should build human relationships to ensure fairness to all parties at all levels.
Organic agriculture should provide a good quality of life for everyone involved, contribute to food sovereignty and reduction of poverty. Organic farming aims to produce the adequacy and availability of food or other products with good quality.
This principle insists that animals should be kept in suitable habitat conditions and the physical properties, natural and well-being.
Natural resources and the environment are used for production and consumption should be managed in a fair way that is socially and ecologically, and preserved for the next generations. It is requires open and fair systems of production, distribution and trade, also consider the social and environmental costs are real.
Organic Agriculture should be managed carefully and responsibly to protect the health and welfare of current and future generations and the environment.
Organic agriculture is a living and dynamic system that answers the demands and conditions that are internal and external. The actors are encouraged organic farming improve efficiency and productivity, but should not endanger the health and well-being.
Therefore, new technologies and methods that already exist need to be assessed and reviewed. Thus, there must be redress for understanding agricultural ecosystems and intact.
This states that precaution and responsibility are the key concerns in management and development of technology that choices in organic agriculture. Scientific knowledge necessary to ensure that organic agriculture is healthy, safe and environmentally friendly. However, scientific knowledge alone is not enough.
Over time, practical experience combined with traditional knowledge into policy and appropriate solution. Organic agriculture should prevent significant risks by applying appropriate technologies and rejecting unpredictable technological consequences, such as genetic engineering. All decisions must consider the values and needs of all who might be affected, through transparent and anticipatory processes. |
354–323 Million Years Ago
During the Mississippian Period (354–323 million years ago), Illinois was 20 degrees south of the equator. The climate was generally warm. Shallow seas covered much of central and southern Illinois. Marine creatures flourished in these seas. Their fossils are preserved in limestone that formed at the bottom of the seas.
Geologists use names to identify layers of sedimentary rock. Layers that
have distinctive characteristics, occur over a wide area, and have recognizable
upper and lower boundaries, are named for localities where they are well
exposed. The locality is followed by the rock type as in “Burlington
Limestone.” If the layer contains several rock types, it is called
a formation as in the “Muldraugh Formation.”
Crinoid Meadow, 340 million years ago
During the Mississippian Period, shallow seas covered much of the midwestern and western United States. Thickets of marine animals called crinoids graced the sea floor. This reconstruction is based on the Early Mississippian Keokuk Limestone of Missouri, Iowa, Illinois, and Indiana, where more than 400 different types of crinoids have been described. This great diversity was possible because each crinoid species had different methods for capturing food.
Click on the Fossils icon below to see the many marine animals that lived during this period. |
Injection molding is a forming process. Material (plastic, metal, ceramic, wax, etc)
is fed into a hopper which delivers it to the feed section of the barrel and screw.
The material is melted usually via a screw that melts or blends the material and
then pushes liquefied material (eg, plastic) into the mold, which forms the part.
The injection-molding industry is relatively young when compared to other
manufacturing processes, such as metals, wood, or cement. Although patented
in 1870 by Smith and Locke and 1872 by Hyatt, the first commercial plunger
machines were developed in the late 1920s and 1930s. Egan patented the reciprocating
screw in 1956. Since then the elements of the machine have stayed the
same but advances continue with the evolution of advanced computer controls, hydraulic
circuits, and computer numerically controlled (CNC) all electric presses.
There are several variations and extensions of injection molding within the industry
that provide unique capabilities to the process and in turn special properties
to parts. Virtually all share the common elements of the following:
(1) Material preparation: The plastic/metal/mixture may be cleaned, dried, colored,
blended, heated, cooled, or in some way readied for use in the machine.
This can be one resin, thermoplastic or thermoset, or combination of
base resin and additives. Additives include colors, metal particles, foaming
agents, antistatic agents, fillers, fibers, flow aids, stabilizers, antioxidants,
mold-release agents, binders, flame retardants, etc.
(2) Material, usually dried plastic granules, is fed (usually by gravity) into a
feed port or throat of a heating cylinder or barrel.
(3) Material melting and/or mixing, [usually thermoplastics via heat (heater
bands) and mechanical shear (flights of a screw shearing the plastic at
inside surface of a barrel wall)], preparing it to be pushed into the cavity:
As the screw rotates, it pumps plastic forward to prepare enough material
for injection. The injection unit, barrel, and screw are now something like
a syringe ready to inject fluid.
(4) Filling the cavity by pushing the material under pressure [7 to ∼414 MPa
(1000–60,000 psi)] into a mold cavity. The cavity sees less pressure, between
1.4 and 140 MPa (200–20,000 psi), because of large pressure losses as the
plastic travels the path to the part. This path includes the nozzle of the
injection-molding machine, the sprue (a tapered cone) that connects
the nozzle to the runner, the runner (usually a round channel), and the
gate or entryway to the part.
(5) The mold or tool that contains the cavity that forms the part and provides
heat to cure thermoset parts or cooling to set up or freeze thermoplastic
parts. Typically, the mold cools the molten plastic to a rigid or semirigid
form so that it can withstand the force of ejection (part removal) and retain
its shape. Not all of the energy to melt the plastic is removed by the mold.
Cooling continues after ejection and the part continues to shrink. Parts
made with certain plastics, ie, semicrystalline, may take 3 days to 6 weeks
to stabilize. Post-molding conditioning can be critical to achieve desired
performance, dimensional criteria, or flatness.
(6) The clamp which holds the mold halves together during filling and packing
the part with plastic.
(7) Part removal or an ejection mechanism. This occurs after the clamp opens,
separating the mold at the parting line into halves. The part is pushed
(ejected) out of the mold and drops to a box, conveyor belt, or is taken out
by a robot.
Fig. 3. Basic hydraulic (toggle clamp) injection-molding machine components. Illustration
by John W. Bozzelli & Rick J. Bujanowski.
Fig. 4. Toggle and hydraulic clamps. Illustrations by Rick J. Bujanowski & John W.
(8) A controller, usually a computer, that coordinates and controls the various
steps of the process and components of the machine.
Figure 3 depicts many of these components in a typical hydraulic injectionmolding
machine with a toggle clamp.
Encyclopedia of Polymer Science and Technology.
Copyright John Wiley & Sons, Inc.
All rights reserved. |
A tumour is a growth caused by an overproduction of cells. A cyst is similar to a tumour, except that it is filled with fluid. Both tumours and cysts can form in the bone of the maxillofacial region, most frequently in the lower jaw bone (jaw tumours).
Benign cysts and tumours of the jaw bone are most often odontogenic, meaning that they originate from tissue related to the teeth. The most frequent kind of odontogenic growth develops near impacted teeth and is called a dentigerous cyst or tumour. It occurs when the follicle of an impacted tooth continues to grow, although the tooth is unable to erupt. This growth can cause the formation of a cyst or tumour that can damage surrounding teeth and bone.
Tumours are frequently benign, but can also be malignant (cancerous). Malignant bone tumours in jaw are either primary, meaning that the cancer originated there, or secondary, meaning that the cancer has metastasized, or spread to the bone of the jaw, from another area of the body. Primary bone cancer in the maxillofacial area is very rare. Malignant tumours in this region are more likely to have metastasized from elsewhere in the body.
Bone cysts and tumours very often do not have any symptoms. They are usually discovered during a routine x-ray, when a bone fracture occurs, or if they swell to a very large size. In some cases, however, they can cause bone pain.
Jaw Cyst Surgery Procedure
Surgery is performed for jaw cyst removal under local or general anaesthesia. In some cases, benign tumours and cysts can be left untreated. However, they usually need to be closely monitored by your doctor. Cells within odontogenic cysts and tumours can occasionally become malignant. But even benign cysts and tumours can also weaken or cause damage to the surrounding bone and tissue if they continue to grow.
Benign cysts and tumours of the bone generally need to be surgically removed. Depending on the nature of the cyst or tumour, a small or a large area of bone may need to be removed. In some cases, bone reconstruction of the area may be necessary. The area of the removed cyst or tumour will be monitored to make sure that it does not recur. Treatment of malignant tumours depends on the type and stage of malignancy.
As a result of the jaw operation, you may experience swelling of the cheek and lips, difficulties swallowing and opening your mouth, and a rise in temperature (up to 39°C). The symptoms will usually cease within 3 to 4 days. After one week the sutures can be removed, and the wound heals completely after about 8 to 10 days. Depending on the size of the cyst, it may take several weeks or months until the bone cavity is completely filled with bone material again.
As with all other surgeries, post-operational bleeding and healing difficulties may occur. To minimize risks, you must carefully complete the case history form so that we can clarify in advance all questions regarding general diseases, allergies, complications after previous surgeries, bleeding behaviour, and medication.
Despite meticulous surgical techniques, nerves and blood vessels around the cyst may be damaged. Root canal treatment or, in the worst case, extraction of the affected teeth may be required.
During the removal of large cysts, there is a risk of damage to the mandibular nerve which may have been displaced due to the growth of the cyst. This results in a generally temporary, rarely lasting sensation of numbness in the affected half of the lower lip. However, the lower lip can still be moved normally. Very rarely, an extremely enlarged lower jaw cyst can cause a fracture of the mandible, which then requires proper treatment.
Behaviour after Surgery
You will be given instructions (pre- and post-operational behaviour) about what you should do before, on, and after the day of your operation. After oral surgery, difficulties in opening your mouth and swallowing are normal and should not worry you. In the case of sustained postoperative bleeding, severe swelling and pain, high fever or general health problems in conjunction with the surgery, you should notify us or your dental specialist immediately. |
A mirror that sends heat into the frigid expanse of space has been designed by scientists to replace air-conditioning units that keep buildings cool on Earth.
Researchers believe the mirror could slash the amount of energy used to control air temperatures in business premises and shopping centres by doing away with power-hungry cooling systems.
Around 15% of the energy used by buildings in the US goes on air conditioning, but the researchers’ calculations suggest that in some cases, the mirror could completely offset the need for extra cooling.
In a rooftop comparison of the device in Stanford, California, scientists found that while a surface painted black reached 60C more than ambient temperature in sunlight, and bare aluminium reached 40C more, the mirror was up to 5C cooler than the surrounding air temperature.
“If you cover significant parts of the roof with this mirror, you can see how much power it can save. You can significantly offset the electricity used for air conditioning,” said Shanhui Fan, an expert in photonics at Stanford University who led the development of the mirror. “In some situations the computations say you can completely offset the air conditioning.”
Buildings warm up in a number of different ways. Hot water boilers and cooking facilities release heat into their immediate surroundings. In hot countries, warm air comes in through doors and windows. Then there is visible light and infra-red radiation from the sun, which also heat up buildings.
The Stanford mirror was designed in such a way that it reflects 97% of the visible light that falls on it. But more importantly, it works as a thermal radiator. When the mirror is warmed up, it releases heat at a specific wavelength of infrared light that passes easily through the atmosphere and out into space.
To make anything cool requires what engineers call a heat sink: somewhere to dump unwanted heat. The heat sink has to be cooler than the object that needs cooling or it will not do its job. For example, a bucket of ice will cool a bottle of wine because it becomes a sink for heat in the liquid. Use a bucket of hot coals and the result will the very different. The Stanford mirror relies on the ultimate heat sink: the universe itself.
The mirror is built from several layers of wafer-thin materials. The first layer is reflective silver. On top of this are alternating layers of silicon dioxide and hafnium oxide. These layers improve the reflectivity, but also turn the mirror into a thermal radiator. When silicon dioxide heats up, it radiates the heat as infrared light at a wavelength of around 10 micrometres. Since there is very little in the atmosphere that absorbs at that wavelength, the heat passes straight out to space. The total thickness of the mirror is around two micrometres, or two thousandths of a millimetre.
“The cold darkness of the universe can be used as a renewable thermodynamic resource, even during the hottest hours of the day,” the scientists write in Nature. In tests, the mirror had a cooling power of 40 watts per square metre at ambient temperature.
Writing in the journal, Fan puts the installed cost of mirrors at between $20 and $70 per square metre and calculates an annual electricity saving of 100MWh per year on a three storey building.
Fan said that the mirror could cool buildings – or other objects – simply by putting it in direct contact with them. Coating the roof of a building with the mirror would prevent heating from sunlight but do little to remove heat from its interior. More likely, the mirror would be used to cool water or some other fluid that would then be pumped around the building.
He ruled out the idea of using the mirrors to slow down global warming. “Roof space accounts for only a small portion of the Earth’s surface, so at this point we don’t think this would be a geoengineering solution. Rather, our contribution on the green house gas emission issue is simply to reduce electricity consumption,” he said.
“I’m really excited by the potential it has and the applications for cooling,” said Marin Soljačić, a physicist at MIT. “You could use this on buildings so you have to spend much less on air conditioning or maybe you wouldn’t need it at all. You could put it on top of shopping malls. With a large enough surface you could get substantial cooling.” |
The effects of carbon on the atmosphere are well documented and it is clear that we are producing far too much carbon for the earth to handle. Living sustainably is obviously the long-term solution, but it requires worldwide cooperation. In my opinion this is only likely to happen when people put the earth before profit, which I cannot see happening in the foreseeable future. Until such a change in mindset occurs there are short-term ideas that can help reduce the amount of carbon in the atmosphere.
I have decided to focus on one short-term idea with a lot of potential, artificial photosynthesis without the use of cells. This may sound like a far-fetched idea. But using a concept devised by Dr. Montemagno, David Wendell and his team studied the foam nests of the Tungara frog and isolated a protein. They used this protein and it unique properties to engineer a type of foam, which can use sunlight to grab carbon from the air around it and turn it into sugar. It does this without harming the environment because it is not an organism.
This artificial photosynthetic foam was found to be incredibly effective in a number of ways. It converts sunlight to sugar at a rate of 16% unlike plants, which do it at 1-5%, also unlike plants it can continue to photosynthesize in carbon intense environments i.e. Factories. The sugars produced can also be used to make high-octane bio fuel. It is for all these reasons that this foam can greatly benefit the environment, reducing carbon in the atmosphere and supplying a carbon neutral energy source. These benefits won it the grand prize at the 2010 Earth Awards. |
However, the rate of increase will vary along with the linear heat flux of the channel. The power
density and linear heat rate will follow the neutron flux shape. However, the temperature
distributions are skewed by the changing capacity of the coolant to remove the heat energy.
Since the coolant increases in temperature as it flows up the channel, the fuel cladding and, thus,
the fuel temperatures are higher in the upper axial region of the core.
A radial temperature profile across a reactor core (assuming all channel coolant flows are equal)
will basically follow the radial power distribution. The areas with the highest heat generation
rate (power) will produce the most heat and have the highest temperatures. A radial temperature
profile for an individual fuel rod and coolant channel is shown in Figure 17. The basic shape
of the profile will be dependent upon the heat transfer coefficient of the various materials
involved. The temperature differential across each material will have to be sufficient to transfer
the heat produced. Therefore, if we know the heat transfer coefficient for each material and the
heat flux, we can calculate peak fuel temperatures for a given coolant temperature.
Figure 17 Radial Temperature Profile Across a
Fuel Rod and Coolant Channel |
Hard of hearing people are those who without assistive devices have limited but functional residual hearing. A person who is not able to hear as well as someone with normal hearing – hearing thresholds of 25 dB or better in both ears – is said to have hearing loss. Hearing loss may be mild, moderate, severe or profound. It can affect one ear or both ears, and leads to difficulty in hearing conversational speech or loud sounds.
‘Hard of hearing’ refers to people with hearing loss ranging from mild to severe. They usually communicate through spoken language and can benefit from hearing aids, cochlear implants and other assistive devices as well as captioning. People with more significant hearing losses may benefit from cochlear implants.
If you or your child hears poorly, this has a major impact on daily life. The biggest challenge facing persons with hearing impairments is communication. People who are hearing impaired, make more effort to follow conversations and get information. They put their other senses extra and are often good at lip reading and reading body language. They may communicate be quite tiring for them. It helps if others consider impairment. Ensuring good communication is the responsibility of both partners. Ask what the other needs during a conversation. Then you can take the best account of his or her impairment.
At Kentalis our audiology centres are providing diagnostics and advice on choice of assistive devices.
Our experts provide specific assistance to learners in mainstream education by supporting both the learners and their teachers. Because the group of hearing is so diverse, we provide support in various ways. Like audience measurement or advice on hearing aids and support on the latest knowledge on around labour. We assist hearing-impaired children in special and mainstream education. |
Franklin Roosevelt is sometimes considered the first "modern" president because of the massive expansion in the power of the state under his administration. Although other Cabinet departments had been added to the government such as the Department of Agriculture created by Lincoln, the Department of Commerce in 1903, and the Department of Labor created during the Wilson administration, Roosevelt drastically increased the power of the president by enlarging the personal staff of the president, creating the first chief of staff and many other positions.
According to Richard Neustadt, in his book Presidential Power, the power of the President is fairly limited, due to the checks and balances in the Constitution. Neustadt evaluates presidential power by considering three different areas: 1) the President's ability to persuade, 2) his or her professional reputation among political insiders, 3) and the prestige the President has with the public, or popular support. Being stronger or weaker in any of these areas critically determines how much power the President has, or as Neustadt says:
Effective influence for the man in the White House stems from three related sources: first are the bargaining advantages inherent in his job with which to persuade other men that what he wants of them is what their own responsibilities require them to do. Second are the expectations of those other men regarding his ability and will to use the various advantages they think he has. Third are those men's estimates of how his public views him and of how their publics may view them if they do what he wants. In short, his power is the product of his vantage points in government, together with his reputation in the Washington community and his prestige outside.How would Trump, Obama, or any other President rate according to these criteria? Are they able to persuade Congress and even their own Cabinets to act? Do they have a good reputation among other people of political influence? Are they popular? According to Neustadt, their overall power derives from these three factors. President Obama's greatest strength may have been his popularity, but in many cases he was unable to persuade the Congress to act, while many political insiders like Hillary Clinton publicly questioned his lack of experience. On the other hand, for legislative proposals he was able to get passed, if you examine the details of how these proposals were passed, the President's persuasive ability plays a great role, even meeting directly with members of Congress to persuade them to vote a certain way. Although insiders may have questioned Obama's lack of experience, on the other hand, he had a good reputation as far as personal ethics went, unlike the Clintons and many other career politicians. Finally, there is good reason to think failure to pass legislation really originates from the Congress' refusal to compromise with the President on most issues. Both interpretations seem credible in their own way. Perhaps, a more critical question would be how well did the President use his popularity, especially compared to past President like Theodore Roosevelt, Andrew Jackson, FDR, and even Lyndon Johnson in the mid 1960s?
A President, himself, affects the flow of power from these sources, though whether they flow freely or run dry he never will decide alone. He makes his personal impact by the things he says and does. Accordingly, his choices of what he should say and do, and how and when, are his means to conserve and tap the sources of his power. Alternatively, choices are the means by which he dissipates his power. The outcome, case by case, will often turn on whether he perceives his risk in power terms and takes account of what he sees before he makes his choice. A President is so uniquely situated and his power so bound up with the uniqueness of his place, that he can count on no one else to be perceptive for him (Neutstadt p. 150).
Stephen Skowronek, in The Politics Presidents Make, describes "presidential cycles" in three parts: that establish "regimes," consolidate regimes, and destroy regimes, leading to another cycle. The idea of cycles, or regimes, suggest there are common features running through successive Presidents, that is, similar norms, values, and ideas. In Skowronek's view there have been at least five presidential cycles beginning with Jefferson: The Jeffersonians, Jacksonians, Republicans, the New Deal, and the Reagan era. Within each cycle, President's perform the role of Reconstruction (starting the cycle), Articulation (strengthening the cycle), and Destruction (ending the cycle beginning a new one). FDR, for example, is seen as beginning the New Deal cycle, articulated by Lyndon Johnson's vision of the "Great Society" in the 1960s, which ended with the Carter administration of the late 1970s. The end of the New Deal cycle has led to a conservative cycle beginning with Ronald Reagan in 1981. George Bush I could be seen as articulating that cycle (or arguably even Bill Clinton since many of his economic ideas were conservative) and perhaps deconstructed with George W. Bush. This would presume that the Obama administration has begun a new cycle, however some would argue that the conservative Republican cycle has still not ended, given the power conservatives still have over politics. In this case, Obama would fit into the pattern similar to Clinton, or even Nixon during the New Deal era.
When Roosevelt ran for president, he was Governor of New York (Herbert H. Lehman, Roosevelt's Lieutenant, was then elected Governor of New York in 1932, the college is named after Lehman––more infamously, the same family as the Lehman Brothers, formerly of Wall St.) Roosevelt advertised what he called his "Brain Trust" a collection of renegade intellectuals who analyzed data, did research, and created the policies that became known as the "New Deal," or new "social contract," between the public and government, leading to a much more active government, the modern welfare state. The FDR administration is known for its "first hundred days," where it created many of the institutions that defined the New Deal, less well known is the great expansion of presidential power in the late 1930s, especially as the U.S. begins to prepare for war with Germany and Japan. In 1939, on its second attempt, The Reorganization Act is passed by Congress, giving Roosevelt the power to create additional federal offices.
Once the president was given the authority by Congress, Roosevelt created several new offices within the executive staff, the Executive Office of the President (EOP) that forms the foundation of the modern White House Office (WHO) today. The executive office is headed by the Chief of Staff who runs the day to day affairs of the president and in many cases controls access to the president. Also, an earlier version of today's Office of Management and Budget (OMB) was created to oversee the expenses of the executive branch in the budget, as well as earlier versions of the National Security Council (1947) and the Council of Economic Advisors (1946).
In all of these cases, offices were to be staffed with scientifically trained officials, overseeing the complex functions of the government. These offices, along with the office of the Vice-President, are "Cabinet-level," equal to Cabinet department. In many cases, presidents have come to rely on the advisors in the EOP more than the Cabinet. Since then, more executive offices have been created like the Office of the Trade Representative (1962); Office of Environmental Quality (1969); and the Office of National Drug Control Policy (1989), as well as others.
After FDR was elected for a completely unprecedented four terms, many began to fear the growing power of the President. The 22nd Amendment was introduced in 1947 and ratified in 1951, explicitly limiting the number of terms a president could serve to two–or a maximum of 10 years if they assumed office as a Vice-President. In between this time, the Republican Party once again came to dominance which culminated the following year when Dwight Eisenhower (1953-1961), the Allied Commander during World War II, was elected President. Despite briefly winning Congress in 1952 when Eisenhower is elected, by 1954 Congress was still in Democratic control again, and would remain so for decades.
The major issue of the election was foreign affairs, specifically the threat of Soviet Communism. During World War II, U.S. propaganda referred to Soviet dictator Joseph Stalin as "Uncle Joe" when the Russians were allies against the Germans. After the defeat of Nazi Germany in 1945, a new conflict emerged between the U.S. and the Soviet Union over the fate of Germany and the rest of Europe. By the end of the 1940s, the conflict had extended throughout the world. It is after this period of time that the U.S. begins to transition into the role of global superpower, a reversal of its traditional non-interventionist, or isolationist, position throughout most of its history dating back to George Washington's administration. The shape and design of many international institutions today are clearly influenced by the U.S. political system, as is the still vague notion of "international law." This has created impressive new challenges to balance the requirements of democratic government with the sensitive nature of geopolitical affairs. In many regards, the demands of specialized technical knowledge has only increased the distance between the government and the public.
The most traditional role the President has had is dealing with foreign nations, especially the command of the military, or "commander-in-Chief." In the post-war era, the Presidency took on the role of maintaining global order.
In 1950, the Korean War began after communist North Korean (supported by China and the Soviets) forces overran the South. The U.S. intervened. This was the first war the U.S. fought since World War II, only five years later. The war turned into a stalemate, after China and the United States both entered the war against each other. The inability to resolve this conflict, contributed to the Democrats' defeat. In 1953, under Eisenhower, a ceasefire was signed, today North and South Korea are still separate. 3-4 million North and South Koreans are estimated to have been killed, and approximately 1 million Chinese soldiers, in what was only a preview of the devastation in East and Southeast Asia in the ensuing decades.
During World War II, Japan conquered the colonial empires of the British and the French in the Pacific and Southeast Asia. The unintended consequence of this created nationalist movements in these countries, fighting, first, the Japanese, and later the European colonial empires. The most important French colony was Indochina. France claimed a right to rule after the war, until 1954 when communist forces in Indochina under Ho Chi Minh defeated the French, leading to the province being split into different countries: Cambodia, Laos, and most notably North and South Vietnam. The French appealed to the U.S. for assistance, filling the void of the departing French. The U.S. tried supporting the South Vietnamese government, until 1963, when the CIA ordered the leader of South Vietnam, Ngo Dinh Diem, to be overthrown, and eventually murdered. The US took direct control over the war (20 days later President John F. Kennedy was assassinated in Dallas, Texas).
In the 1960s, the conservative movement started to reassert itself after its devastating losses in the 1930s and 1940s. What had happened to the Republican Party in the 1930s was similar to the Democratic Party in the 1860s. It became so identified with something so negative (slavery, or causing the Great Depression in this case) that it took literally decades for it to repair the damage to its image. In the 1950s, a Republican president reigned, but Eisenhower had adopted virtually every major program introduced by the New Deal. It was under Eisenhower the first school desegregations were ordered, like Little Rock, Arkansas in 1954. In 1964, the Republicans ran Arizona Senator, Barry Goldwater against Lyndon B. Johnson (1963-1969), Kennedy's former Vice-President, and someone who modeled himself after FDR, even calling himself LBJ. Johnson won in one of the biggest landslides in American history.
|1964 U.S. Presidential Election|
At the time, in American political culture, there was a strong commitment among the public for social welfare policies and programs for the poor. Programs like Medicare and Medicaid were created under the Johnson administration as well as the new Cabinet Department, the Department of Housing and Urban Development (HUD). Johnson also presided over the passage of the Civil Rights Act of 1964, outlawing legal segregation and the Voting Rights Act of 1965. Along with these landmark legislative acts, the "Civil Rights" Amendments were passed in the Constitution:
- 23rd Amendment (1961): Allows Washington D.C. to vote for president which previously had no representation in the electoral college.
- 24th Amendment (1964): Prohibits a poll tax, literally a fee paid to vote used especially in the South.
- 25th Amendment (1967): Establishes the presidential line-of-succession, like the 20th and 22nd amendments, this amendment reflects the growth of executive power and its importance.
- 26th Amendment (1971): Passed during the height of the Vietnam War, this amendment lowers the voting age to 18 from 21.
Three of these Constitutional amendments deal with the crucial issue of the right to vote in a democracy which was also the focus of the Voting Rights Act of 1965. However, electoral laws are mainly decided by the state, and there has recently been a determined effort by many Republican governors of states like Florida to "purge" registered voters from the voting lists and thus take away their right to vote under the pretext of preventing "voter fraud." It might seem strange that a party that claims to be working in the interest of the majority of people would put so much effort into reducing the number of eligible voters, and many liberals have argued this is an attempt to undermine the Voting Rights Act.
After Kennedy's suspicious assassination in late 1963, plans were set in motion to start the war in Vietnam in 1964, a fake assault on U.S. naval vessels in the Gulf of Tonkin was used as a justification. By 1968, over 500,000 U.S. military personnel were in Vietnam. The combined stresses of Johnson's spending on domestic social programs and foreign wars, creates inflation, and confidence in the dollar declines worldwide.
The United States became the dominant economic power in the world after World War II. At one point, responsible for almost half of the world's entire industrial output. This was the material basis of the so-called "Baby Boom" in the United States, reaping the full benefits of U.S. post-war prosperity in the 1940s, 50s, and 60s. It is during this period of time, with the assistance of Hollywood movie magic, the mythical image of the American way of life is created. Always a suburban fantasy to a large extent, as many older American cities show significant signs of decay by the 1960s. Of course, it was basically only a fantasy for white men as well. Often unacknowledged is the super prosperity of the U.S. during this time was due to other major industrial powers of the world rebuilding from World War II. The two most dominant industrial powers besides the U.S., before World War II, were Germany and Japan. By the late 1960s, and especially in the 1970s, exports from these countries were eroding U.S. economic power. Arguably, the U.S. has never recovered from this and has pursued a series of artificial means of preserving itself largely through uncontrolled deficit spending, both public and private.
|Trade Statistics 1930-2005|
Bureau of Economic Analysis
The public assassination of John F. Kennedy in 1963, was echoed by the deaths of Martin Luther King Jr. and Robert F. Kennedy, the brother of John, assassinated in April and June 1968.
Robert Kennedy had been the favorite in the upcoming Democratic primary for the election in November. Instead, they nominated pro-war Hubert Humphrey. Republican Richard Nixon was elected president in 1968, and re-elected again in 1972, although the illegal tactics used during his re-election, such as Watergate, would lead to his downfall and resignation in 1974, the only president so far to resign in office.
A major factor was that after 1964, the Democratic party largely lost the Southern vote to Republicans. The Democrats had been a force in the South since the founding of the party in the 1790s. Johnson reportedly remarked as he was signing the Civil Rights Act in 1964, "we have lost the South for a generation." Many have accused Nixon and other Republican presidential candidates as playing to Southern racism without being explicit about it, sometimes called "symbolic racism" or "institutional racism."
|1968 U.S. Presidential Election|
George Wallace was a segregationist third party candidate
In 1968, Nixon had won the Republican primary against a number of challengers including Ronald Reagan, the Governor of California. After three attempts, Reagan would be elected president in 1980, thus signaling a backlash against the progressive values of the 1960s and 70s.
The Reagan administration was defined by the phrase "government is the problem" and tried to eliminate most government regulations of business. Despite claims to reduce the deficit, the budget deficit of the federal government tripled through the decade, along with an increasing trade deficit growing rapidly since the 1970s.
The budget deficit grew largely because of a combination of increased military spending and significant tax cuts given to the highest income brackets in the country. Reagan was later forced to reverse many of these tax cuts and ended up raising taxes several times. Much of the increased military spending was used to finance covert wars in Latin America and the Middle East, but also to "outspend" the Russians on defense, a process that some believe helped pushed the Soviet Union into its downward spiral.
The trade deficit continued to grow in the face of competition from Germany and Japan after the 1960s, and the inability of major U.S. corporations like General Motors to adapt and innovate their product designs, as well as decreasing quality in the automobiles, compounded by multiple Arab oil embargoes in 1973 and 1979. Despite advances in several high-tech U.S. industries revolving around the emerging computer industry in the 1980s, the U.S.'s overall trade deficit continues to rise even today. This did not prevent President Reagan from winning the largest landslide in American history, over a weak Democratic party, still haunted by its past. Despite this, the House of Representatives maintained a Democratic majority throughout the entire Reagan administration. The Senate was recaptured for the first time in 30 years by the Republicans in 1980, but reverted back to Democratic control in 1986 after numerous Reagan scandals. It was not until 1994 when Republicans were able to take both houses of Congress and hold on to them for more than one election.
|1984 U.S. Presidential Election|
The U.S. economy grew during the Reagan administration, but the distribution of the wealth is concentrated in fewer hands. Poverty increased during the Reagan administration at the same time in which scandals emerged over Reagan's administration misallocating funds for the poor (literally stealing from the poor to give to the rich) and secret funding of right-wing "contras" in Nicaragua. Many commentators pronounced the return of the "Gilded Age."
In 2008 the biggest stock market crash since the Great Depression occurred resulting from financial speculation in the U.S. housing markets. This was in large part a result of the "deregulation" of the financial industry beginning in the 1980s, overturning laws established in the 1930, but it was the repeal of legislation separating commercial and investment banks, signed into law by Bill Clinton, that many economists argue greatly increased the magnitude of this crisis. Unlike the Great Depression which began in the middle of a Republican administration and helped to discredit the Republicans for more than 40 years, this one exploded, or was timed to explode, shortly before a presidential election, the 2008 election which saw the election of Barack Obama.
|2008 U.S. Presidential Election|
"Battleground" states are states that do not have either a solid Republican or Democratic majority
In many regards the divisions into North and South regions still exists
President Obama tried to adhere to a "consensus" approach to politics which produced mixed results at best. Much like Jefferson, another controversial figure of his time, appeals to the unity between Federalists and Republicans, Obama has in many of his speeches appealed to common sentiments between Democrats and Republicans. However, unlike Jefferson whose party came to dominate politics in America, the Obama administration did not have a clear majority in Congress (at least since 2011). As a result, he has had great difficulty in getting legislation passed, although, despite this opposition, some of the signature legislation passed during this time were the economic stimulus program in 2009 that supporters argue helped avert another great depression, the Dodd-Frank bill that provides some limited oversight and regulation of the financial industry, and the Affordable Care Act, more commonly known as "Obamacare." The ability of Congress to limit the President is a function of the system of checks and balances, as intended in the Constitution, but as critics have pointed out, often this system creates paralysis in government.
President Obama, for obvious ideological reasons, seeks to portray himself in the lineage of Jefferson and Lincoln. Obama addresses the issue of race in a way Lincoln never could by drawing upon his own experiences with racism, especially as a child of mixed race who has insight into the attitudes of whites and blacks, in his speech on race, considered by many to be his best speech.
As most Democrats look to the New Deal era of FDR and LBJ as the high-point of the Democratic party in the modern era, he has tried to expand upon these policies. Most notably, healthcare which Roosevelt declared was a right, and advanced by Johnson who established Medicare and Medicaid. The current president has also kept in place the coercive and surveillance apparatus created during the Bush administration to fight the "war on terror."
Although winning the election of 2012, it is obvious that the Obama administration has been unable to achieve the massive victories that other Presidents were able to, notably: FDR, LBJ, Nixon and Reagan. Note also the similarities between the election results of the previous election, and the changes in certain "battleground states." Although President Obama has presided over one of the most polarized presidential administrations, it is likely the incumbent after the 2016 election may face an even more embattled presidency, as the intense political and social antagonisms that run through American life, and reflected in its government, show no signs of relaxing.
After the 2016 election, what lessons can be drawn? If we think of each election as a specific outcome, what explanations or what causes can we find that gives us a clear understanding? First, racism, sexism, homophobia, and bigotry in general play a role in every election. If you look at the number of votes, less people voted for Trump than voted for Mitt Romney or Bush in 2004, so the notion of a white backlash might not be as strong as people think, the real question is why did so few people vote for Hillary Clinton? As we all know, Trump lost the popular vote, and both candidates failed to get a majority of the popular vote (about 48% each). Trump won in many Mid-West states that have been particularly hard hit by economic policies over the last 20-30 years, and many feel it was Trump's vague promises of bringing jobs back that won his support even among unionized workers who normally vote Democratic and who voted for Obama in 2008 and 2012 (Clinton won just over half of union workers). Trump also did surprisingly well among minority voters, "According to exit polls, Trump lost Hispanics 65–29, besting the performance of the mild-mannered and courtly Mitt Romney, who, despite being about as likely to utter an ethnic slur as Pope Francis, lost Hispanics 72–27." To get almost 30 percent of the vote is pretty astounding considering Trump's racial rhetoric. Also:
"With blacks, exit polls show Trump claimed 8 percent of the vote to the previous Republican nominee's 6 percent.
That means Trump — who called Mexicans "rapists" and "killers" — garnered more support from Hispanics than a candidate whose most controversial position was telling undocumented immigrants to "self-deport."
Trump has frequently linked blacks to "inner city" slums and crime at rallies. Yet he performed better among African American voters than a considerably more moderate Republican nominee."
The electoral college also amplifies the influence of certain states and regions of the country, and so by losing all those industrial states, Clinton lost just enough electoral votes to put Trump over the top, even though again as in 2000 winning the popular vote. Voter suppression in states like Florida and North Carolina most likely played a role as well. Democracy Now states that almost 900 polling places were closed between the 2012 and 2016 election, making it harder to vote, increasing the wait time at some places, as well as other restrictions designed to make it harder to vote. I think the lingering question though, is what would have happened if Bernie Sanders ran against Trump, would he have won? Also, how will Democrats in Congress fight against Trump and a Republican majority in Congress? During the first years of the Obama administration, Republicans were able to stall most legislative attempts because the Democrats lacked a 60 vote "supermajority," something the Republicans lack now. Democrats in the Senate, including Bernie Sanders, will have to play this role now, and to some extent have.
After two years, Trump got his Muslim ban through the courts. His immigration policy is being carried out every day, something carried on under Democrats as well. He has pushed through another massive tax cut with no public debate. He has had little resistance in Cabinet, judicial, or other appointments including Gina Haspel. The now filled Supreme Court has already made several decisions restricting civil, political, and social rights. He made the Democrats cave in over funding the government without providing funding for DACA. Many Democrats voted for his appointments, his tax bill, and lifting regulations on banks, as well as increases in military spending (which would be affected by a government shutdown). Again, this is helped by a Republican majority, but where are all the Democrats ready to filibuster, where is the so-called resistance? If anything, the most common complaint is that Trump is not displaying enough militaristic strength with Vladimir Putin. It would seem Trump is a fairly powerful president in Neustadt's terms, but where does the source of his strength lie?
Assignment: Choose a passage from the speeches by JFK, Reagan, or Obama. Write out the passage, explain the meaning of it, and why you chose this particular passage. |
For six decades, the U.S. Fish and Wildlife Service has monitored the population of the last wild migratory flock of whooping cranes primarily via an annual census. Now, Aransas National Wildlife Refuge and the National Wildlife Refuge Systems Inventory and Monitoring (I&M) program are devising a way to improve that count.
The flock of endangered cranes migrates between nesting territory near Canadas Wood Buffalo National Park and wintering territory near Aransas Refuge on the Gulf Coast of Texas.
In 1950, the first whooping crane aerial census found 31 cranes, all wintering within 20,000 acres of salt marsh at Aransas Refuge. Since then, the population has grown to almost 300 birds and expanded onto 140,000 acres of salt marsh, some refuge land, some privately owned. Technological advancesincluding GPS (Global Positioning System) and highresolution satellite imageshave been huge. Yet the cranemonitoring method has changed little.
So, refuge and I&M staffs are developing a formal protocol for monitoring wintering whooping cranes. The protocol will describe the surveys objectives, sampling design, field methods and data analysis procedures. It will be submitted soon for professional peer review to ensure that the methods are scientifically defensible and professionally valuable.
Although still in draft stage, the protocol updates the method. Previously, one observer flew over the wintering grounds and marked the location of cranes on paper maps. The planes flight paths often were different, which resulted in some areas being searched more thoroughly than others. The new method will use two observers searching out opposite sides of the aircraft while navigating along evenly spaced transects. GPSequipped laptops will record the cranes locations digitally on highresolution satellite images. This will improve data collection consistency.
The protocol also updates how we analyze the data, so we can be confident in the resultswhich is vital to the Service mission and in line with the Conserving the Future visions call for sound science. The previous method was coined a censusbecause it was assumed that the population and search area were small enough to count each bird without error. But as the population grew, the chances of counting each bird decreased, and the censuss design did not allow the Service to gauge reliability.
The draft protocol includes a survey method called distance sampling. It is useful even when some whooping cranes are missed. For more than 30 years, distance sampling has been successful for counting wildlife from whales to deer. By measuring the distance each group of cranes is from the aircraft and using distance sampling, refuge staff members can credibly estimate the number of cranes present, even when they dont see them all.
The refuge and I&M staffs thoroughly tested a distancesampling approach before trying it with live cranes. They analyzed data from previous surveys and learned that nearly 95 percent of the whooping cranes recorded were less than 500 meters from the plane. They flew experimental surveys and learned the new method could accurately estimate the number of crane decoys present. They tested conventional distance sampling against a cuttingedge modification and learned that better results were obtained by incorporating crane locations and habitat information into the analysis.
More than 60 years of Service census data have taught biologists a lot about where the whooping crane population has been. The new method, which retains much of the old, now provides statistically defensible estimates of abundance, while providing a better understanding of how whooping cranes use habitats. These innovations help the Service continue recovery of North Americas largest endangered bird by informing conservation planning, land protection efforts and policy decisions.
Brad Strobel is a wildlife biologistuntil recently at Aransas National Wildlife Refuge in Texas and now at Necedah Refuge in Wisconsin. |
Agroforestry is a system that combines methods developed in the fields of agriculture and forestry in order to promote sustainability. Agroforestry promotes the planting of trees that can potentially become agriculturally productive [source: World Agroforestry Centre]. Aesthetic value is not a central principle of agroforestry. Rather, the aim of landowners who implement agroforesty methods of growth is to derive specific benefits from the trees that they've planted.
Since human consumption is a major reason for the Earth's diminishing resources, one step toward replenishment is the implementation of certain agroforesty practices. In general, agroforestry is used on large tracts of land, including rangelands and farm lands. In theory, however, the principles and practices that comprise the agroforestry resources management system can be applied to all fertile lands. Several common agroforestry practices have proven successful. For example, alley cropping is a method that entails the planting of trees between shrubs or other trees that are already grown in. Another agroforestry practice is the planting and growth of trees, called riparian forest buffers, near bodies of water. Another principle of agroforestry is the integration of forestry and grazing land, which is called silvopasture. Agroforestry also offers a solution to dealing with the more damaging effects of wind on soil moisture by the planting of windbreaks, which are strategically planted shrubs and/or trees [source University of Illinois].
Beyond these agroforesty practices, a landowner also needs to decide which trees to plant. Different trees have different roles to fulfill. For example, fertilizer trees are especially useful for soil health and land regeneration. On the other hand, fodder trees are a good idea if a forester is looking to improve livestock production. |
Earth is enveloped in a mantle of air and contains numerous layers of gases. The temperature of the Sun is greater than that of Earth. The rays of Sun take a trip through the atmosphere to arrive at the final destination that is Earth and provide warmth to Earth and the heat from the Earth travels back to the atmosphere. Some gases in the atmosphere defend some of the warmth from evading into the space. These gases are known as “greenhouse gases” and this whole process is known as “greenhouse effect” since its working is same as that of the greenhouse. Due to some reasons such as from deforestation and the emission of Carbon dioxide from burning fossil fuels, the Earth’s average temperature is increasing.
The bodies of all the living things are adapted to certain weather conditions. Due to the rise in temperature, the lives of human beings are affecting all over the world. For example, seals and polar bears have to search for new lands for hunting and living, if the ice in the Arctic melts. Most of the plants and animals may not be able to cope with these climatic changes and may die. This can cause the loss of some plant and animal species in certain areas of the world. Although, global warming affects everyone, human beings are at a greater risk due to it. For example, countries near the coastal areas suffer from a greater risk of flood.
How do the global warming effects on humans work?
Global warming is making the Earth very hot and hence level of pollen in the atmosphere is becoming higher. Due to extreme heat more people are dying from cardiovascular as well as respiratory disease. More than 7000 excess deaths were recorded in Europe due to the heat waves of summer in the year 2003. Due to high temperature, the level of Ozone and other pollutants rises and hence more people are suffering from respiratory disease. The global warming effects on humans depend on how people adapt to the changes or how can they reduce the climate changes in the world by making their contribution.
How do variable rainfall and natural disasters play their role in casting effects of global warming on humans?
Increasingly variable rainfall is likely to affect the supply of clean and fresh drinking water. Lack of pure and safe water can increase the risk of diarrhea. In extreme cases, drought and famine are caused due to water scarcity. Drought will increase the prevalence of malnutrition which is a cause of 3.5 million deaths per year currently. By the end of 2090, climate change will double the frequency of extreme drought, widen the areas affected by drought and increase their average duration six-fold.
Floods are also increasing in intensity and frequency. Floods heighten the risk of water borne disease, contaminate fresh water supplies and produce breeding grounds for mosquitoes and disease carrying insects.
Today, the number of weather related natural disasters has tripled and are causing 60, 000 deaths every year in developing countries. Rising sea level and extreme weather conditions will destroy medical facility, homes and other essential services. People living near the sea will be forced to move, which heightens the risk of health problems because they are adapted to live near sea only. Global warming effects on humans have put forth an alarming state for the human race and if measures are not taken to control the level of pollution, Earth would become unfit for human race to survive for long. |
5 June 2014
Titan (or Saturn VI) is the largest moon of Saturn. It is the only natural satellite known to have a dense atmosphere, and the only object other than Earth for which clear evidence of stable bodies of surface liquid has been found.
Titan is the sixth ellipsoidal moon from Saturn. Frequently described as a planet-like moon, Titan has a diameter 50% larger than Earth’s natural satellite, the Moon, and is 80% more massive. It is the second-largest moon in the Solar System, after Jupiter’s moon Ganymede, and is larger by volume than the smallest planet, Mercury, although only 40% as massive. Discovered in 1655 by the Dutch astronomer Christiaan Huygens, Titan was the first known moon of Saturn, and the fifth known satellite of another planet. |
FORM: Refers to an object’s shape and structure, either in two dimensions (ex: a figure painted) or three dimensions (ex: a statue carved)
COMPOSTION: Refers to how an artist organizes (compose) forms in an artwork, either by placing shapes on a flat surface or by arranging forms in space.
MATERIAL: To create art forms, artists shape materials (pigment, clay, stone, gold etc.) with tools (pen, brushes, chisels, and so forth) Each of the materials and tools available has its own potentialities and limitations.
TECHNIQUE: The process artist employ such as applying paint to silk with a brush, and the distinctive, personal ways they handle materials constitute their technique.
LINE: MOST IMPORTANT ELEMENTS DEFINING ARTWORK’S SHAPE OR FORM is line. The path of a point moving in space, an invisible line of sight.
COLOR: Light reveals all colors. As the sum of all wavelengths composing the visible spectrum, natural light may be disassembled or fragmented into the individual colors of the spectral band.
TEXTURE: Refers to the quality of a surface, such as rough or shiny.
SPACE: The bounded or boundless “ container” of objects.
MASS: The bulk, density, and weight of matter in space. VOLUME and MASS describe both the exterior and interior forms of a work of art.
CARVING & CASTING: Carving is a subtractive technique. The final form is a reduction of the original mass. In additive sculpture, the artist builds up the forms, usually in clay around a framework. Or a sculptor may fashion a mold, hollow form for shaping, or casting.
RELIEF SCULPTURE: The subjects project from the background but remain part of it.
PERSPECTIVE AND FORESHORTENING: Perspective is A device to create the illusion of depth or space on a two dimensional surface. Foreshortening is when an object appears compressed when seen from a particular viewpoint, and the effect of perspective causes distortion.
PROPORTION AND SCALE:... |
There is a popular one liner which finds relevance to the Indian society:
” In India, you do not cast your vote, you vote your caste” .
Such is the prevalence of the caste system. It has seeped in through the roots of the society and has entrenched itself such that it has become an organic part of it.
Now, before critically evaluating it, let us understand what this “caste system” is all about.
- It finds its roots in the ancient India.
- During that period, it was called varnashrama.
- Varnashrama: a graded division of labour, which was as follows:
- Brahmin : Priestly class or the intellectuals.
- Kshatriyas: Kings and Administrators.
- Vaishyas: traders and merchants.
- Shudras: they were meant to serve the above three varnas.
- The underlying purpose of this system was an organised distribution of labour in the society.
- As also mentioned in various texts like Bhagwad Gita, under this system, people of the different varnas were meant to perform their prescribed duty(dharma).
- According to Jawahar Lal Nehru’s Discovery of India, the varnas were formed by the Aryans(who were primarily tillers) in order to distribute the work in the society.
Transition from varnashrama to caste system:
However, with time and the alterations in attitude and aptitude, this system turned into what is presently called as the caste system.
- The priestly class or the Brahmins who were the most dominating of all sections due to the status they received in the society, misused their position.
- This ,in turn, led to discrimination of the lower classes.
- Also, the system became more or less hierarchical. It means that the scions of the intellectuals, who may or may not match the required intellect level, will be called Brahmin as they are born in that family.
- This annulled the meritocratic element in the system.
- Thus, a Brahmin prejudice began to prevail and this created the system of upper and lower in the society.
- This was the beginning of the present caste system.
Lal Bahadur Shastri was ‘apparently’* the second Prime Minister of the Republic of India. A Gandhian by ideals, he was an honest and simple personality.
In this post, some light will be thrown on the considerable contribution and thoughts. beliefs and principles of this jewel of the independent INDIA.
- Was an active part of the national movement. He served as a young Satyagrahi beginning from 1921 till independence.
- An ardent follower of Gandhian policies and philosophy of Gandhiji.
- Worked for the upliftment of Harijans as a part of the Servants of India Society(of Gokhale) and also as a Gandhian Satyagrahi(Gandhi Ji upheld truce between mass movements to serve and include the Harijans).
- Spent around 9 years in jail during independence activism.
The major political role of Shastri Ji began after the independence of India in 1947. The following shows the roles played by Shastri Ji in various spheres.
- Political sphere:
- Served as the Railway Minister under the Nehru cabinet. Resigned from the cabinet after a railway accident. This depicted the sense of moral responsibility and accountability imbibed in him.
- He was a near unanimous choice for the role of Prime Minister after the demise of Pandit Nehru.
- His decision making was a perfect combination of idealism and realism.
- Economic Sphere:
- White Revolution took place under his term–> supported the initiatives of Amul Co-operative society and facilitated setting up of the National Dairy Development Board.
- In 1960s, India was suffering from food shortages. Here, Shastri invoked his idealist policy and urged the citizens to give up one meal of the day. Reduced demand of food could per facilitate pita availability of food to masses. Hailed as “Shastri Vrta“, it had a considerable impact in short-term.
- Promoted the Green Revolution(which was intended to make India self-sufficient on food production).
- Food Corporation of India was setup under his term.
- Believed in ending License Raj(a socialist policy).
- Foreign Policy:
- The policy of Non-alignment in a more realistic manner–> built up ties with the Soviet Union.
- Enhanced the defence budget looking at the increasing enmity against India amongst the neighbours.
- Highlight: War with Pakistan in the year 1965 –> gave Indian forces a free hand–> Indian forces aggressively occupied a major area of Pakistan–>a war in favor of India–> ended with an agreement at Tashkent to restore status quo.
- Jai Jawan, Jai Kisan:
- This was the highlight of all his actions and policies.
- Jai Jawan: Hail the soldier–>particularly relevant to 1965 war.
- Jai Kisan: Hail the farmer–> 1960s –> famines and food shortages–> farmer had to play a key role in sufficing the food needs.
Lal Bahadur Shastri is considered to be one of the very important cogs in the wheel that is called INDIA. His contribution in the economic(in particular agriculture) and foreign policy spheres is still relevant and acclaimed by the people from all walks.
*Gulzari Lal Nanda, though, was the acting PM for the hiatus period between Nehru and Shastri, but generally Shastri is considered to be the apparent second PM.
Recently(on 28th September 2016), 109th birth anniversary of Shaheed Bhagat Singh was observed.
Bhagat Singh was one of the infinite jewels which adorned India during the struggle for independence. The gravity of his contributions is still felt and revered by the people not just in India but across the globe.
This article will be a brief of Bhagat Singh’s role in the National movement, his contributions, the events which shaped his actions and thoughts among others.
In a chronological order , it goes like this:
- At the age of 12 years, traumatized by the Jallianwala Bagh massacre(under the helm of General Dyer). This was a major event in the early stage of his life which imbibed considerable bitterness against the Britishers.
- In the beginning, supported Gandhi Ji and his strategies of Satyagraha and Non-violence in the beginning and took part in the Non-Cooperation Movement
- But–>irked by the Gandhian policies after withdrawal of the Non-Cooperation movement post the Chauri Chaura violent incident(1922)*
- He was now inspired by the anarchist* and Marxist ideology*.
- Began to involve himself in revolutionary activities and upheld violence to overthrow the British Raj.
- Became a prominent part of the Hindustan Republican Association(HRA), an organization comprising of revolutionaries like Ram Prasad Bismil, Ashfaqullah Khan, Chandrashekhar Azad among others.
- Kakori conspiracy*(1925) was a setback for HRA.
- Formed Punjab Naujawan Bharat Sabha (a left-wing organization to gather youth and peasants by educating them about ideologies like socialism etc.) in 1926
- Chandrashekhar Azad, Bhagat Singh, Sukhdev among others laid the foundation of the Hindustan Socialist Republic Association(HSRA) in 1928.
- The word “socialist” in HSRA was added on Singh’s insistence. This confirms his propensity towards socialism*.
- Simon Commission and death of Lala Lajpat Rai was one of the turning points in his activities.
- Lala Lajpat Rai was beaten to death by police while protesting against the arrival of Simon Commission(1928).*
- In order to avenge his death, Bhagat Singh, Sukhdev, Rajguru and Chandrashekhar Azad conspired to kill the Supridentent of Police(SP), Scott. However, due to mistaken identity, they shot dead ASP, Sauders.
- Bombing the Central Legislative Assembly:
- Bhagat Singh along with Batukeshwar Dutt.
- The purpose was to “make the deaf hear”(to voice their concerns regarding the British rule) . However, the bomb was harmless.
- To protest against the Public Safety Bill* and the Trade Disputes Act*.
- Was inspired by French revolutionaries.
- “Inquilab Zindabad” was the voiced slogan. It means- “Long live the revolution”.
- Charged with Saunder’s murder, bombing legislative assembly and manufacturing bomb–> arrested as a political prisoner.
- 116 day Hunger strike against the pity conditions and abominable treatment meted out to the Indian prisoners–>demanded equal treatment for European and Indian prisoners.
- Executed along with Sukhdev and Rajguru on 23rd March 1931.
Bhagat Singh: Thoughts and Beliefs
- Rationalist: upheld reason as the source of valid knowledge.
- Atheist-> questioned religious ideologies , particularly after witnessing inter-religious riots –> this was an outcome of his rationalist outlook.
- Socialist–> inspired by the Russian(Bolshevik) Revolution which upheld Socialist ideology.
- Towards the end, he himself admitted the effectiveness of the leadership of Gandhi Ji and called to abrogate violence.
- Anarchist: upheld absence of the British state.
- Chauri Chaura incident(1922): A violent breakout of the masses against the police. Police allegedly used force on the peacefully protesting masses. Mahatma Gandhi called off the Non Cooperation movement due to this event as the principle of Non-violence was breached. Bhagat Singh and other young nationalists were disillusioned by this.
- Anarchism: An ideology which denies any role of state. It upholds the principle : ” State is an unnecessary evil”.
- Marxism: an ideology which upholds the principle of struggle of the working class(proletariat) against the bourgeoisie(capitalist or ruling class).
- Kakori Conspiracy: train robbery took place in Kakori(U.P) led by HRA revolutionaries in 1925.
- Socialism: means of production and distribution to be owned by the community as a whole.
- Simon Commission(1929): a commission sent to INDIA for constitutional reforms—>Opposed by the nationalists on grounds that it had no INDIAN member.
- Public safety bill: To stop communist activities by suppressing communist organizations.
- Trade Disputes act: restrictions on strike action, mass picketing, forbade unions from having political objectives. |
SAN DIEGO, California -- The decline of Caribbean coral reefs has been linked to the recent effects of human-induced climate change. However, new research led by scientists at Scripps Institution of Oceanography at UC San Diego suggests an even earlier cause. The bad news – humans are still to blame. The good news – relatively simple policy changes can hinder further coral reef decline.
Employing a novel excavation technique to reconstruct the timeline of historical change in coral reefs located on the Caribbean side of Panama, a team of scientists led by Scripps alumna Katie Cramer and current Scripps Professor of Oceanography and Smithsonian Tropical Research Institute (STRI) Emeritus Staff Scientist Jeremy Jackson has determined that damage to coral reefs from land clearing and overfishing pre-dates damage caused by anthropogenic climate change by at least decades.
"This study is the first to quantitatively show that the cumulative effects of deforestation and possibly overfishing were degrading Caribbean coral and molluscan communities long before climate change impacts began to really devastate reefs," said lead author Cramer, currently based at the Global Coral Reef Monitoring Network at the International Union for Conservation of Nature.
Coral reefs have suffered alarmingly since the 1980s due to coral bleaching and coral disease, thought to stem from the warming of the oceans due to anthropogenic, or human-induced, climate change. However, until recently, the impact of prior human activities on Caribbean coral reefs had not been studied with experimental techniques.
Historical records and qualitative surveys provide hints that declines in corals in some parts of the Caribbean occurred as far back as the early 1900s after coastal lands began to be cleared to make way for plantations. However, the current study is the first to quantify the changes that reef corals and mollusks have undergone as a result of long-term stress caused by the deposition of silt, nutrients, and pollution onto coral reefs from land clearing and the depletion of reef fish that prevent algae from overtaking reefs.
"Because researchers did not really begin to study Caribbean reefs in detail until the late 1970s, we don't have a clear understanding of why these reefs have changed so dramatically since this time," said Cramer. "So, we set out to reconstruct an older timeline of change on reefs by looking at the remains of past reefs – coral skeletons and mollusk shells."
To reconstruct this timeline, the team dug below modern reefs in incremental layers and, using radiocarbon dating of the coral skeletons they found, linked fluctuations in the types and numbers of coral and mollusks over time to historical records of land clearing. Changes in the relative numbers of these various species represent clear indicators of the overall health of the coral reef.
The team also improved upon the standard technique of taking long, narrow core samples of coral fossils that cannot track fluctuations in the numbers of larger species of coral.
"We wanted to look at the whole complement of the coral community," said Cramer.
To catalog the relative numbers of dozens of coral and molluscan species, the researchers dug two-foot-wide by three-foot-deep pits into reefs at several coastal lagoon and offshore sites near Bocas del Toro, Panama, that were heavily affected and less affected by land runoff, respectively. At each of these sites they also conducted surveys and recorded the composition of living corals.
"We dug up over a ton of coral rubble and tens of thousands of shells," said Cramer, who led the fieldwork at STRI and likened the laborious experience to doing underwater construction.
Systematically sifting through the coral and shell fossils, the scientists noted several indicators of environmental stress, including a decrease in the overall size of bivalves such as oysters, clams, and scallops, a transition from branching to non-branching species of coral, and large declines in the staghorn coral and the tree oyster, which were once the dominant coral and bivalve on these reefs.
These indicators were observed in layers of the excavated pits at coastal lagoon sites that were dated before 1960 and as far back as the 1800s, corresponding to a period of extensive deforestation in the Bocas del Toro region. Similar evidence of environmental stress at offshore sites was dated after 1960, indicating that the negative impacts of land clearing have more recently begun to affect reefs further offshore.
With the decline of the branching coral species, the reefs now have fewer nooks and crannies that are used as habitat for reef fish and other organisms. Also, the non-branching species that have taken their place grow at a much slower rate. "Consequently, there is less of a chance that the reefs will be able to keep up with sea level rise from climate change," said Cramer.
"Because the governments of the world have yet to undertake any meaningful efforts to mitigate climate change, it is of the utmost importance that locally caused stressors to reefs such as overfishing and deforestation are minimized," said Cramer. "Advocating for more intelligent use of land as well as implementing sustainable fisheries management, those are things that can be done right now."
Views expressed in this article do not necessarily reflect those of UnderwaterTimes.com, its staff or its advertisers. |
The Santa Barbara’s (A robotics club at California University) robot is able to look through the compact walls by using Wi-Fi signals. The robot has some important applications such as search and rescue, detection, surveillance and archeology. It has also the ability to identify the shape and position of invisible objects in a scanned structure. The robot can also categorize the composition of objects as flesh, metal, or timber.
The robot can work in pair and traverse object perimeter or structure and the Wi-Fi radio signals are alternately transmitted and received between one another through the scanning object. The robot also uses a model of wave-propagation for exploiting the transmitted and received signal for showing the hidden object’s presence. It can produce an actual map of the detailing structure for locating solid objects and spaces by measuring the received signals.
Each robot can easily estimate their own position and the other robot’s position, area and different objects. It is capable to do it for its speed and travel distance ranges. For positioning, it uses a wheel encoder and a gyroscope. The researcher’s team now planning to include laser guidance to increase the spatial accuracy and for improving the captured image map resolution. |
Website Creation Tutorial Terms
- Frames - Frames are a method of allowing more than one HTML file page to be loaded in a web browser window. Many webcrawlers do not search to web pages that are linked from a frameset page.
- HTML - HTML stands for Hypertext Markup Language and is the format most web documents are placed in to be made available for viewing. HTML is simply used to indicate to the web browser, how to display the content. It uses elements consisting of sets of tags (beginning and end tag) to mark the type of elements such as paragraphs, headers, lists, and tables.
- Search engine - A search engine is a web site that searches web listings. The web listings may be provide by categorized sites such as dmoz.org or they may be created by web crawlers. Search engines allow web surfers to find websites that have information based on keyword search criteria. Some search engines are edited by humans and some are done with automatic programs such as webcrawlers.
- SSI - Server Side Includes are normally used to place the same notices on many pages. This way, if the notice is changed, multiple pages do not need to be edited. Only the notice page is changed. Ste the CTDP SSI manual for technical information about SSI.
- Web crawler - A web crawler is a program that goes to web sites and creates an index of pages based on a description, title, and keywords found in the web page header and in the content. |
Fluorescent light bulbs are lamps that use the phenomena of fluorescence to produce light. Fluorescence is the emission of radiation by a substance that is exposed to an external source of radiation. They are much more efficient than traditional incandescent bulbs, since incandescent bulbs waste most of their energy producing heat rather than light.
Fluorescent bulbs consist of glass tubes filled with low pressure mercury-argon vapor. The inner wall of the tube is coated with a white phosphor. A heated filament emits electrons into the vapor, causing the vapor atoms to emit ultraviolet light. This ultraviolet light is then absorbed by the white phosphor and re-emitted as visible light.
While running, fluorescent lights send pulses of electricity (electrons) through the tube to cause this effect. As a result, the light emitted by these lights also pulses. However, most people can not detect the pulsing under normal conditions, because they take place so rapidly that the light emissions appear constant. Although the pulse rates vary depending on the kind of florescent light bulb, they generally run at a rate of about 120 cycles per second (120 Hz).
- A problem common to many is that compact fluorescent lights (CFLs) are designed to have the tube on top, and the compact ballast below. So, they are designed such that in upright sockets, this is the case. However, when sockets are sidways, they tend to function for as long before failing, presumably due to overheating. This problem is much worse with inverted sockets. When a CFL light is installed in one of these, the tube ends up on the bottom and the ballast on top. Heat from the tube rises directly into the ballast, and tends to build up there, having few ways to escape.
- Since the pule rate (about 120 Hz) is well above the speed that the human eye can seem to generally detect (50–60 Hz), it seems that there should be no problem with the use of these. However, there have been notable increases in reports of headaches, eye strain, dizziness, and general eye discomfort in some places when fluorescent lights are installed. High frequency electronic ballasts (which run at a rate of at least 20,000 Hz) seem to significantly reduce these problems, (by up to 50%) but not eliminate them.
However, some counter these statistics by saying that the pulse rate is simply to great to be noticed. They say hypothesize that these problems could be caused by radio frequency radiation (or Radio Frequency Interference/RFI) generated by the ballasts.
- It has been noted that as fluorescent lights age, they tend to produce modulating light emissions. For example, the U.S. National Library of Medicine did a survey of their own fluorescent lights, and found that 42% of their lights were modulating brightness up to 20% and occasionally even 30%. In other words, 42% of their lights were fluctuating their brilliance by about 20%. These fluctuations are noticeable, and can be especially problematic for people with epilepsy, although they may also cause the headaches, and eye strain others sometimes notice as well.
- Fluorescent lighting, headaches and eye-strain. A. J. Wilkins, I. Nimmo-Smith, I., A. Slater & L. Bedocs. Lighting Research and Technology, 1989. Vol. 21, 11-18 |
OK, what does it take to make the aquariums shown in the previous slides work? Plants have
There are many terms associated with lighting. Some are useful to us and some are not.
All bulbs are rated in terms of watts. This is simply the power the bulb consumes and only roughly translates to brightness since some bulbs are more efficient or use better phosphors. Since all bulbs have a watts rating, you typically see rules of thumb such as "3 watts per gallon" for a planted tank. This is a starting point but is not very accurate since a lot depends on the type of bulb.
Lumens are a better measure of the brightness of a bulb. More lumens means a brighter bulb. However, lumens are used to describe how your eyes see the brightness, NOT how the plants see it. A bulb with lots of green in the spectrum will have a high lumen value but wonít help your plants much. Also, lumens is the total output from the bulb; it doesn't say how much gets to your plants. That's a function of how well your reflector works.
Lux is a measure of light intensity. One lux = one lumen per square meter. This shows how much light is actually getting to a specific plant. Naturally, a bulb canít be specified in lux because it depends on the reflector, distance from the bulb, shadows and all kinds of other effects. But if you had a lux meter and you knew how many lux a plant needed, you could determine if you needed more or better bulbs. As a side note, lux is also based on how a human sees the intensity, not a plant. But it's a good relative measure.
Color temperature in degrees Kelvin (K) describes the overall spectrum of the bulb. It refers to the color a "radiating black body" would be if heated to that temperature. A lower temperature is a redder color (incandescent light is about 2700K) and higher temperature is bluer. Daylight is around 5500K. Plants do well and look best in temperature ranges between 5000K and 7000K.
Color Rendering Index (CRI) describes how well a source renders colors to the human eye compared to sunlight. 100 (%) is perfect. Any bulb over 90 is adequate for our purposes and will make the plants look close to natural.
Fluorescent bulbs are usually rated for how long they last, 10000 hours to 30000 hours. This depends on the number of starts, temperature, etc. Bulbs lose intensity over time and should be changed before they burn out. Six months to one year is a good target for replacement. Try to stagger replacement times so that all the bulbs arenít changed at once.
|Slide 14 Here are some specs for some typical bulbs. These are all 40w bulbs but notice the difference in lumens and CRI, especially the GE "Gro&Sho" plant bulb. We like the Penn-Plax Ultra Tri-Lux - very bright and good color rendition. It works great in combination with Triton bulbs.|
Now that we have some background, let's talk about plant needs.
To meet general lighting requirements, we recommend
"Full Spectrum" usually means tri-phosphor bulbs (three different phosphors instead of the
Tri-phosphor fluorescent lighting is usually the brightest per watt and provides good color (example: Tritons, PennPlax Ultra Tri-Lux, Coralife Trichromatic)
Photosynthesis requires a certain energy threshold - just any old light may not do it.
Beyond a certain brightness, light is wasted.
1.5 to 3 watts per gallon is a good start. Use lower w/g if you use better bulbs. We
have 160 watts (2 Tri-Lux,2 Triton) on 100 gallon tanks (1.6 w/g).
Use more watts if:
This tank is a 24" high 90 gallon tank and has a metal halide hood suspended over it. The
two 175W bulbs themselves are 14" from the water surface. So even though it's almost "4
watts per gallon", the surface intensity is the same as a tank with 4 40w fluorescent
bulbs 4" from the water (15000 lux).
Light varies with distance from the bulb:
The duration or photoperiod is important. If itís too short, the plants won't photosynthesize
long enough and won't have optimum growth. If it's too long, the plants will stop
photosynthesizing naturally ("go to sleep") and the light is only being used by algae.
A longer period can not make up for inadequate intensity.
You should use timers to regulate the period. We've tried having a dark period in the afternoon based on the theory that afternoon thunderstorms were common in the tropics and the interruption in light slowed algae growth. It didnít affect algae and killed off some light-loving plants.
Many aquarists are intimidated by water chemistry. In reality, there is nothing to be afraid
of - all you need to know to be successful with plants is some simple hardness terms and
how pH and CO2 are related.
Although there are many varied, interrelated and confusing terms for water hardness, only two are useful to us and are easily measured. Both types of hardness can be expressed in German degrees (dH) or in parts per million (ppm) or milligrams per liter (mg/l). The terms ppm and mg/l are the same; 1 dH = 17.9 ppm = 17.9 mg/l.
Most hardness kits return values as "Calcium Carbonate (CaCO3) equivalents". This simply means "the same amount of hardness as would be produced by that much CaCO3" no matter what the actual source of the hardness. This tends to confuse many people. Don't worry about it - just concentrate on the measured values.
General Hardness or "GH" in German terms is the amount of calcium and magnesium in the water, nothing more, nothing less. When a fish or plant is said to prefer hard water, it is GH that is the critical parameter. GH is easily measured with the Tetra GH Hardness test kit. Be wary of test kits that measure "total hardness" or other terms - make sure they are measuring calcium (Ca) and magnesium (Mg) only.
Carbonate Hardness or "KH" is the amount of bicarbonate (HCO3-) or carbonate (CO3--) ions in the water. The Tetra KH Hardness test kit will measure carbonate hardness but there is a caveat. There is a more general term called "alkalinity" that refers to the amount of acid buffering in the water (how well the water can resist a change in pH as acid is added). Donít confuse alkalinity with "alkaline water" - they are not the same. Anyway, carbonate hardness is one component of alkalinity. Another common source of alkalinity is phosphate - if you use pH-UP or pH-DOWN, you are adding alkalinity to the water (to resist pH changes) but you are not increasing KH. To put it another way, which is important to us, if carbonates are the only buffer in your water, alkalinity and carbonate hardness are the same thing!
Why is this important? Because carbonate hardness can not be measured directly! The Tetra KH test kit is actually an alkalinity test kit that assumes carbonates are the only buffer in the water. If other buffers are present, the KH reading will be falsely high. How do you know if other buffers are present? You generally donít unless you have a phosphate test kit or you start with water of very low KH and add your own in the form of sodium bicarbonate (plain old baking soda).
People get GH and KH mixed up a lot. Although "hard" water is usually high in both GH and KH, they are really independent. They are commonly seen together because naturally hard water usually comes from areas with limestone in the aquifer. Limestone is calcium carbonate (CaCO3), which will add both GH (in the form of calcium) and KH (in the form of carbonate) to the water.
So, what does all this mean? Simple! Decide on a GH value that is suitable for your fish and plants. A good general value for a planted community tank is 5 dGH or about 100 ppm. If you have soft water, add some calcium carbonate and a little Epsom salts (magnesium sulfate, MgSO4) to increase the GH. If you have hard water, mix your tap water with distilled or Reverse Osmosis (RO) water to soften it.
Carbonate hardness is a little more complicated. You need some KH (actually, alkalinity)
to prevent pH swings or crashes as acid is added to the water through nitrification. As
you add KH, the pH will increase in proportion. If you aren't using CO2 injection, 2-3 dKH
will give you good buffering and will produce a pH of about 7.3 or so depending on your tap
If you do use CO2 injection, KH plays an important role. Just as adding KH increases pH, adding CO2 lowers pH. There is a well defined relationship between KH, CO2 and pH (I'll get to that next). Anyway, CO2 injection is key to good plant growth so we have an ideal situation - a good KH level provides a stable pH and the CO2 injection allows us to set a specific pH.
This chart shows how KH, CO2 and pH are related. An important note: this chart is only true
if carbonates are the only buffer in the water. If phosphates or other buffers are
present, this chart is useless!
Letís take an example here. Suppose your tap water has 0.5 dKH and 1.5 mg/l of dissolved CO2 (a very typical case). In this case, your pH will be 7.0 (if bicarbonates are the only buffer present!). Now if we add enough sodium bicarbonate to get to 5 dKH (for good buffering), the pH will increase to 8.0. But, if we inject enough CO2 to give us 15 mg/l (for good plant growth), the CO2 will bring the pH back down to 7.0. The CO2 and KH balance each other and we have:
I prefer this chart to the table in the last slide - it's easier to read. This shows that
too much CO2 can be dangerous (>40 ppm) and shows the desired range of pH, CO2 and KH
in the green area.
By adjusting the KH and amount of CO2 in the water, you can pick any pH you want (within reason). However, you can NOT set CO2 levels or KH levels by trying to change pH. Anything you do to change pH (other than changing KH or CO2) will either be temporary (like foolishly adding acid) or will negate the chart (like adding phosphate buffers).
I said water chemistry is simple - here are the only tools and supplies you need to adjust
water hardness. The Tetra hardness test kits are shown on the left. They are cheap and
simple to use.
We use chemicals from a chemical supply house for calcium carbonate and sodium bicarbonate. You can find this in other places. Baking soda can be bought at a grocery stores and calcium carbonate can be found in home brewing or wine-making stores.
Carbon dioxide is a little more complicated. There is some info in the handout for a simple
do-it-yourself (DIY) yeast CO2 generator to experiment with before jumping into CO2 with both
When you do jump, a proper setup with a compressed gas bottle, regulator, gauges, solenoid and valves can run from $150 to $200.
This shows "CO2 in action". The CO2 bottle feeds gas through a regulator, solenoid valve and
fine adjustment valve, into a "bubble counter" so you can see the flow (bubbles per second)
and into a CO2 reactor in a trickle filter sump. A pH controller (not shown) turns the CO2
on and off to maintain a specific pH of 7.0 +/- 0.05.
This is an example of the high tech side of aquascaping. Most setups are much simpler.
To grow, plants need the right "food" and "vitamins" just like we do. The basic building
blocks are materials the plant needs to build tissue - things like hydrogen, oxygen and
carbon. These can be thought of as "meat and potatoes" for plants. They are supplied by
water (H2O) and carbon dioxide (CO2).
Major nutrients are also required but in smaller amounts. Sort of like "peas and carrots" for plants. These include nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. Most of these are supplied naturally in an aquarium, either from fish waste or from our attempts at "water chemistry". As a matter of fact, it is sometimes a major effort to limit things like N and P (but keep in mind, "zero" is not a good goal!).
The final things are trace elements, which are like vitamins. You can do OK without supplements but the old "One-A-Day" regimen keeps you healthy and strong. Trace elements are usually supplied via commercial fertilizers like Duplaplant tablets and drops and other commercial products.
We have been using the Dupla products since 1987 and have had great success with them. They
cost a lot to buy but they are very concentrated - on a "per dose" basis, they cost about the
same as other products.
Shown are Duplaplant tablets (added at water changes based on the amount of new water) and Duplaplant-24 daily drops containing supplemental iron. Extra iron is needed daily since it rapidly oxidizes in the water - plants can utilize iron in the Fe++ (ferrous) state but cannot use it in the oxidized Fe+++ (ferric) state.
Also shown are Duplarit-K laterite balls. These are made from baked iron rich clay and can be inserted in the substrate near the roots of plants which are heavy feeders - things like Echinodorus sword plants.
|Slide 29 Duplaplant-24 drops are added daily in the morning when we check the tanks and top off the water. It comes in a convenient dropper bottle. We use 4-6 drops in a 90 gallon tank but that will vary with the types and amount of plants. You should monitor iron with a high quality iron test kit and strive to get about 0.1 mg/l of iron in the water.|
A planted aquarium is a bit more complicated to run than a fish-only tank since the plants
must depend on the environment to supply all their needs. They can't wander around looking
for leftover food or go up to the surface to gasp for air if things aren't going well.
One important part of the environment is stable water quality. Some plants, like the \ Cryptocorynes, can actually "melt down" if the water quality or other parameters are unstable. Our methods to ensure stable water quality are:
Another important part of the environment is the substrate. Plants use the substrate as an
anchor and as a source of food. Obviously, any old gravel that is not too coarse will anchor
the plants but supply nutrients is a different story. Some important considerations for a
|Slide 32 We like to use a quartz sandblasting gravel known as Tex-Blast (I think it is also available as pool filter gravel). It's a nice light brown color and has the right grain size. It's shown here with a Barclaya longifolia and some Malaysian Trumpet Snails.|
To add warmth to the substrate and to provide water movement via convection currents, we use
Dupla substrate heating coils. These go on the bottom of the tank under the gravel and provide
a concentrated heat source. This causes the water around them to heat up and rise, allowing
cooler water to move down to the bottom.
This photo shows a 250 watt coil on the bottom of a 90 gallon tank. This is really too much for the tank (150 watts would be better) but we didn't know that when we bought them. The tank was a glass, open-top discus tank to be kept at 84 F and we thought we needed more wattage due to these factors. However, the important factor is the length of the cable - more wattage means a longer cable. We had to cram this one in with tighter than normal spacing! It still works fine, though.
|Slide 34 We mix Duplarit-G laterite in the lower 1/3 of the gravel (1 kilogram or 2.2 pounds for a 100 gallon tank). This provides a source of iron initially and the clay will act to capture and hold nutrients brought down via the convection currents. The laterite is only added to the lower 1/3 so that the other 2/3 will seal it in and prevent the tank water from turning red.|
|Slide 35 Here is a drawing of the heating coils, substrate and nutrients in action. Plants are able to adsorb iron, ammonium, CO2 and trace elements through their leaves and roots. They also respire O2 when they are photosynthesizing. The heating coils in the substrate generate warm and cool zones, creating convection currents and bringing the water-borne nutrients into the substrate. The clay in the laterite has negative binding sites which hold the positively charged nutrients ions (Fe++, NH4+) until plant roots can adsorb them. The water brought into the substrate also brings oxygen, keeping the substrate from going anaerobic.|
Another factor in the environment is filtration. What is needed is really only mechanical
filtration and good water movement - the plants themselves act as biological and chemical
filters. However, with a high fish load, a little supplemental biological filtration is a
good safety factor.
The filter should create a strong water movement (but not an underwater hurricane!) but without too much surface turbulence which will drive off CO2.
The type of filter is not important but we prefer trickle filters for their convenience. The sump is a nice place to hide CO2 reactors and heaters, they provide a good surface skimming action to remove protein or bacterial films and the usually have a strong pump to provide good water flow.
|Slide 37 This photo shows our 90 gallon setup with a trickle filter. The skimmer box is to the left and there are two water return lines in the right and left corners. The left return exits lower in the tank and points to the center front while the right return is toward the surface and also points to the center front. This high/low scheme provides a nice circular movement.|
What about the ever-popular chemical filtration products that seem to take up half the shelf
space in a typical fish shop? Fuhgettaboutit! Plants will provide all the chemical
filtration you need and, more than likely, the chemical filtration products will just
wreak havoc with your water chemistry and fertilizers! A good planted tank has:
And the final factor in the environment is the fish population. Choose your specimen fish
carefully and be sure to include a variety of "housekeepers".
Avoid plant eaters (herbivores) and gravel diggers - you don't need help in arranging the aquascaping!
Select some catfish like corydoras to clean up uneaten food.
Provide a variety of algae eaters - different types will eat different forms of algae. Good choices are "Siamese Algae Eaters", Otocinclus, Farlowella and Ancistrus. Avoid "Flying Foxes" and "Chinese Algae Eaters" - they become aggressive when they are adults.
|Slide 40 Siamese Algae Eaters (Crossocheilus siamensis), sometimes called "Siamese Flying Foxes", are often difficult to find. Most times you have to mail order them. They are a lighter color than normal flying foxes and have a rough-edged black stripe. Flying Foxes have a very sharp-edged black stripe with a thinner bronze stripe just above it. In the stores, SAE are usually 1-2" long. This plump adult is about 6" long. A juvenile is right behind it. The SAE are the only fish known to eat the "Black Beard Algae" that is common on slow growing plants like Anubias. SAEs are invaluable in a planted tank.|
|Slide 41 This is a Farlowella acus on a swordplant stem. They have a reputation as being difficult fish but we have never had problems with them. We have some that are 3 or 4 years old. Maybe the "problem" has simply been a lack of algae in their diet!|
Finally, a word about maintenance. DO IT! Ok, two words. A planted tank needs more
maintenance than a fish-only tank to keep it looking good and to keep it healthy. Some
things to consider:
Feeding the fish and plants. Feeding the fish is usually obvious, but people sometimes forget that plants eat, too. With the Duplaplant-24 daily drops, it's easy to make a habit out of it.
Daily inspections are important. You set up a plant tank for it's attractiveness so look at it daily. You may notice that algae is cropping up or the plants may look yellow - both are signs that the iron level s may not be right. Your plants will tell you when something is not right - pay attention to them.
Keep the filters clean. Another obvious thing but it is easily overlooked since the filters are generally hidden from view. If you let the filters go too long, they will become nitrate generators as all the captured crud decomposes.
We can not stress enough the importance of regular, partial water changes. 25% to 50% every two weeks is a good idea. Remember, even though the plants are pretty good filters, they generate waste as well and changing water is the only way to remove these waste products as well as keeping nitrates under control. This is also a good time to trim plants and check water chemistry.
Plants grow and they grow fast if you treat them right. It is not unusual to have to trim fast growing plants every two weeks. A nicely arranged aquascape doesnít stay nice very long - the plants donít seem to care that they are messing up your carefully designed underwater garden.
And donít forget to monitor the major factors - pH, carbonate hardness, iron and nitrates. After you have some experience, you can easily tell when something is not right but at first you have no basis for judgement. Using your test kits every so often and correlating those readings with physical appearances is the only way to become experienced.
So, a quick summary of plant basics:
OK, so enough of the details already. Let's see some pretty pictures as proof that all this
works! All the following photos are from our tanks at various stages in their evolution.
We have tried a variety of equipment and will point out what works and what doesnít work.
This first slide is an 85 gallon Rainbowfish tank. This tank has an undergravel filter (!) but it is run with power heads instead of airlift tubes. The turbulence caused by air bubbles will quickly defeat any efforts to inject CO2. Here we have only two Hagen 201 power heads for the entire 60" long tank to avoid too much water circulation in the gravel. A common myth is that you can't grow plants with an UGF - I hope this photo puts that rumor to rest. We have had some of the lushest stem plant growth in this tank.
One drawback to an UGF is the need for more maintenance. We find that we need to pull up the plants every six months or so and give the gravel a good vacuuming. The UGF pulls detritus into the substrate providing the needed negative binding sites like laterite, but too much a good thing is, well, too much!
This is a 100 gallon discus tank that was setup with laterite but without the expensive
under gravel heating coils. It uses a trickle filter. Note the variety of plants growing
in the 84 F water. Some may take longer to acclimate to the higher temperature but very
few plants will not grow in warmer water.
We found that the tank did very well without heating coils for at least 18 months but then we began to experience a slow down in plant growth and an upsurge in algae.
This is our 90 gallon open-top tank. It is much like the discus tank except it does have
substrate heating coils plus it uses a suspended metal halide hood instead of fluorescent
lights. With the heating coils, it has never experienced any instabilities, reduction in
plant growth or algae. It ran perfectly for 5 years before we had to tear to down when we
remodeled the house.
Notice the emersed plants. The busy plant to the left is Hygrophila corymbosa and the big plant in the middle is Echinodorus osiris. The open top really allows a spectacular display. There is a shelf behind the tank with houseplants on it that really benefit from the bright light. |
Student Research Page
If you don't have a copy of the TPW magazine, you may print a copy of Mysterious Monarchs (pdf).
Wow, look at all those Monarch butterflies! These Monarchs are migrating to another location.
Monarch Migration Flyways
Every year, Monarchs migrate across North America. Paths that migrating birds or butterflies follow are called "flyways" meaning the way that they follow as they fly. The monarchs have their own flyways. The North American Monarch breeding population is split into eastern and western populations divided by the Rocky Mountains. By far the larger of the two populations is the eastern population. Most of these butterflies fly south though Texas' Central Flyway on the way to their wintering grounds in central Mexico. In addition to Texas' two flyways, some Monarchs fly to Mexico from the west or across the Gulf of Mexico. Besides central Mexico, other smaller overwintering colonies occur on the coasts of California, Florida and Texas. Monarchs breed as far north in the Summer as Milkweed grows in southern Canada.
Here's an example of where Monarchs migrated across Texas. The paths can change slightly each year. The dots represent reports send in from citizens who are part of Monarch Watch. Do you live near one of the flyways?
Keeping It Wild!
Learn About Monarchs!
Look closely to see the difference between a male and female Monarch!
Monarchs are the only butterflies known to make long distance migrations. They are members of a tropical family that cannot survive cold winters. North American monarchs migrate south in the fall to California, Mexico or Florida. On the way north in the spring they lay eggs. It's the young produced by those and the next generation's eggs that return all the way north and start south again.
Monarchs lay their eggs on milkweed plants. Female monarchs can lay between 400 and 600 eggs. Their caterpillars absorb the poisons produced by the plant and become poisonous themselves. Birds that try to eat monarchs or their caterpillars become ill. They quickly learn that monarchs are not good to eat. Other butterflies, such as Queens and Viceroys, copy the colors of monarchs so that birds won't eat them either.
Adults feed on flower nectar. Caterpillars feed on plant leaves, preferring milkweeds and dogbanes. Monarchs must eat a lot to store fat to use as an energy source during cold weather.
Adult monarch butterflies are orange above with black veins and white spotted wing borders. Males have a black scent patch on a vein across the middle of the hind wing.
Monarchs return by the tens or hundreds of thousands to the same groves of trees each winter. They are sluggish during the winter and feed only on warm days. Humans are trying to protect these important places by creating butterfly preserves. Researchers study monarch migration by tagging individual butterflies to see where, how far and how fast they travel.
Monarchs occur wherever milkweeds grow. Monarchs are found all over Texas, the U.S., southern Canada and Mexico to central America. There are also breeding populations in Hawaii and Australia.
Can you spot the matching monarchs?
Plant a butterfly garden!
Journey North: Track the monarch's journey. Watch for monarchs that are flying, resting and refueling.
Science Museum of Minnesota
Monarch Butterly Site: Information about gardening, rearing, and student activities
Life Cycle of the Monarch (Chicago Nature Museum YouTube video) |
What are Gram-negative germs?
Gram-negative germs make up a large group of germs that can be found in water, in soil, and on plants. Many Gram-negative germs live in the human digestive tract (colon). Some Gram-negative germs can be found on the skin of healthy people.
Not every one gets an illness from Gram-negative germs. But if these germs invade parts of the body where they are not commonly found, they can cause serious illness. Illnesses caused by Gram-negative germs can range from pneumonia and urinary tract infections to blood stream and wound infections.
Antibiotics may not kill these germs
Some germs can develop clever ways to outsmart the drugs (antibiotics) used to kill them. In this case, we say the germs are resistant to the drugs. As germs become resistant to one drug, scientists develop new and stronger drugs to kill those germs.
Having a resistant germ means that some of the commonly preferred drugs can no longer kill the germ. This means the choice of drugs that your doctor can use is limited if you become sick.
Who gets Gram-negative germ illnesses?
People most likely to get sick with resistant Gram-negative germs are those who:
- Are seriously ill
- Are in the hospital for a long time
- Have taken many antibiotics or drugs used to destroy bacteria
- Have a disease that prevents the body from fighting infection
- Have been in a nursing home or long-term care setting
- Are on a ventilator or breathing machine
Resistant Gram-negative germs can be spread by person-to-person contact and contact with the environment. If you get a Gram-negative infection, you will be placed on Contact Precautions for the rest of your hospital stay. This means that special measures will be used to stop the spread of resistant germs to other patients. Some of these special measures are listed below.
- You may be placed in a private room or a semi-private room with another person
who has a similar condition.
- Health care staff may wear protective clothing, such as a gown and gloves, when giving you care.
- Your family and visitors may need to wear gown and gloves when they visit you.
- Some of your patient care items may have to stay in your room.
- You may be asked to stay in your room. You may be asked not to go to the patient lounges or cafeteria.
Clean hands prevent the spread of germs
Keeping hands clean is the most important step to prevent the spread of germs. Either wash your hands with soap and water or use a waterless hand cleaner, which may contain alcohol. This waterless hand cleaner is available in your room. You may use the waterless hand cleaner as long as you do not see any dirt or soil of any kind on your hands. If you do see anything on your hands, you should use soap and water to clean them.
Be sure to clean your hands before you eat, after you use the bathroom or bedpan, and before you leave your room. Your family and visitors should clean their hands before they enter and leave your room, after they help care for you, and before they eat.
When you go home
- When you are discharged from the hospital, you can return to your normal routine as your doctor tells you.
- At home, good hand washing or hand cleaning is important for every person in the house.
- Laundry and dishes can be done as usual.
- No special household cleaning is needed.
If you have any questions, please ask your doctor or nurse. You also may contact the hospital’s Infection Control Department. Please tell your nurse that you want to do so.
Reviewed August 2013 |
Diffusion is the net (overall) movement of particles from an area of high concentration to an area of lower concentration.
When you put a drop of red dye into a glass of water, the dye diffuses until it is at equal concentration everywhere in solution.
A difference in concentration of a particle between two areas is called a concentration gradient. Diffusion occurs down a concentration gradient.
Diffusion is a passive process; it does not require energy.
Diffusion is fundamental to how organisms function:
- Proteins diffuse within the cytoplasm of cells.
- Carbon dioxide diffuses from the air into cells in the leaf for photosynthesis.
- Oxygen diffuses from the blood into tissues for respiration.
Organisms can control concentration gradients to determine the direction of diffusion. |
Role morality is the notion that people sometimes fail to live up to their own ethical standards because they see themselves as playing a certain role that excuses them from those standards.
For example, say a person views herself as a loyal employee of a company. In that role, she might act unethically to benefit her employer in ways that she would never do to help herself. To paraphrase researcher Keith Levitt, the same person may make a completely different decision based on what hat – or occupational role – she may be wearing at the time, often without even realizing it.
In one study people were asked to judge the morality of a company selling a drug that caused unnecessary deaths when its competitors’ drugs did not. 97% of people concluded that it would be unethical to sell the drug. Then, the researchers placed different people into groups, and asked each group to assume the role of the company’s directors. Acting as directors, every one of the 57 groups decided to sell the drug. They framed the issue as a business decision in dollars-and-cents terms. They ignored the harmful impact their decision would have on others.
So, ethical behavior requires maintaining the same moral standards regardless of the roles we play at home, at work, or in society. |
Choice Boards - Geometry - 2nd Grade
First and foremost, I have to give a huge shout out and thank you to the one and only Jennifer Findley from Teaching to Inspire in 5th, for so kindly giving me her permission and blessing to create a second grade version of her amazing choice boards.
In this unit you will find 4 choice boards. These boards have 3 mini choice boards, one for each second grade Geometry standard and 1 choice board for the Geometry domain.
On each mini choice board, you will find 8 activities for your students to use based on the math strand. Some of the activities will require items that are listed on the materials list. These activities work well to broaden students’ understanding of the Common Core Math Geometry standards for second grade.
These choice boards are perfect for homework, early finishers, independent work time or math centers.
These choice boards come in both a full color format and a black and white format.
Only a few simple materials are needed to use with this set of choice boards:
magazines for cutting
rulers for drawing straight lines |
Cross Curriculum Priorities
Aboriginal and Torres Strait Islander Histories and Cultures
A_TSICP2 The occupation and colonisation of Australia by the British, under the now overturned doctrine of terra nullius, were experienced by First Nations Australians as an invasion that denied their occupation of, and connection to, Country/Place.
A_TSICP1 First Nations communities of Australia maintain a deep connection to, and responsibility for, Country/Place and have holistic values and belief systems that are connected to the land, sea, sky and waterways.
A_TSICP3 The First Peoples of Australia are the Traditional Owners of Country/Place, protected in Australian Law by the Native Title Act 1993 which recognises pre-existing sovereignty, continuing systems of law and customs, and connection to Country/Place. This recognised legal right provides for economic sustainability and a voice into the development and management of Country/Place.
A_TSIP3 The significant and ongoing contributions of First Nations Australians and their histories and cultures are acknowledged locally, nationally and globally.
AC9HH10K09 The causes of First Nations Australians' campaigns for rights and freedoms before 1965, such as discriminatory legislation and policies, the 1938 Day of Mourning and the Stolen Generations
AC9HH10K10 The contributions of significant individuals and groups in the campaign for the recognition of the rights of First Nations Australians and the extent to which they brought change to Australian society
AC9HH10K11 The significant events and methods in the movement for the civil rights of First Nations Australians and the extent to which they contributed to change
AC9HH10K13 The continuing efforts to create change in the civil rights and freedoms in Australia, for First Nations Australians, migrants and women
AC9HH10K18 continuities and changes in perspectives, responses, beliefs and values that have influenced the Australian way of life
AC9HH10S01 Develop and modify a range of historical questions about the past to inform historical inquiry
AC9HH10S02 Locate, identify and compare primary and secondary sources to use in a historical inquiry
AC9HH10S04 Explain the usefulness of primary and secondary sources, and the reliability of the information as evidence
AC9HH10S06 Compare perspectives in sources and explain how these are influenced by significant events, ideas, locations, beliefs and values
AC9HH10S07 Analyse different and contested historical interpretations
AC9HH10S08 Create descriptions, explanations and historical arguments, using historical knowledge, concepts and terms that incorporate and acknowledge evidence from sources
AC9HG10K01 The human-induced changes that challenge the sustainability of places and environments
AC9HG10K03 First Nations Australians’ approaches to custodial responsibility and environmental management in different regions of Australia
AC9HG10K07 Reasons for, and consequences of, spatial variations in human wellbeing in Australia, including for First Nations Australians
AC9E10LA01 Understand how language can have inclusive and exclusive social effects, and can empower or disempower people
AC9E10LE01 Analyse representations of individuals, groups and places and evaluate how they reflect their context in literary texts by First Nations Australian, and wide-ranging Australian and world authors
AC9E10LE04 Evaluate the social, moral or ethical positions represented in literature
AC9E10LY01 Analyse and evaluate how people, places, events and concepts are represented in texts and reflect contexts
AC9E10LY02 Listen to spoken texts and explain the purposes and effects of text structures and language features, and use interaction skills to discuss and present an opinion about these texts
AC9E10LY05 Integrate comprehension strategies such as visualising, predicting, connecting, summarising, monitoring, questioning and inferring to analyse and interpret complex and abstract ideas
AC9E10LY06 Plan, create, edit and publish written and multimodal texts, organising, expanding and developing ideas through experimenting with text structures, language features, literary devices and multimodal features for specific purposes and audiences in ways that may be imaginative, reflective, informative, persuasive, analytical and/or critical
AC9HC10S02 Locate, select and compare information, data and ideas from a range of sources
AC9HC10S03 Analyse information, data and ideas about political, legal or civic issues to identify and evaluate differences in perspectives and interpretations |
MIT physicists have discovered a new quantum bit, or “qubit,” in the form of vibrating pairs of atoms known as fermions. They found that when pairs of fermions are chilled and trapped in an optical lattice, the particles can exist simultaneously in two states — a weird quantum phenomenon known as superposition. In this case, the atoms held a superposition of two vibrational states, in which the pair wobbled against each other while also swinging in sync, at the same time.
The team was able to maintain this state of superposition among hundreds of vibrating pairs of fermions. In so doing, they achieved a new “quantum register,” or system of qubits, that appears to be robust over relatively long periods of time. The discovery, published today in the journal Nature, demonstrates that such wobbly qubits could be a promising foundation for future quantum computers.
A qubit represents a basic unit of quantum computing. Where a classical bit in today’s computers carries out a series of logical operations starting from one of either two states, 0 or 1, a qubit can exist in a superposition of both states. While in this delicate in-between state, a qubit should be able to simultaneously communicate with many other qubits and process multiple streams of information at a time, to quickly solve problems that would take classical computers years to process.
There are many types of qubits, some of which are engineered and others that exist naturally. Most qubits are notoriously fickle, either unable to maintain their superposition or unwilling to communicate with other qubits.
By comparison, the MIT team’s new qubit appears to be extremely robust, able to maintain a superposition between two vibrational states, even in the midst of environmental noise, for up to 10 seconds. The team believes the new vibrating qubits could be made to briefly interact, and potentially carry out tens of thousands of operations in the blink of an eye.
“We estimate it should take only a millisecond for these qubits to interact, so we can hope for 10,000 operations during that coherence time, which could be competitive with other platforms,” says Martin Zwierlein, the Thomas A. Frank Professor of Physics at MIT. “So, there is concrete hope toward making these qubits compute.”
Zwierlein is a co-author on the paper, along with lead author Thomas Hartke, Botond Oreg, and Ningyuan Jia, who are all members of MIT’s Research Laboratory of Electronics.
The team’s discovery initially happened by chance. Zwierlein’s group studies the behavior of atoms at ultracold, super-low densities. When atoms are chilled to temperatures a millionth that of interstellar space, and isolated at densities a millionth that of air, quantum phenomena and novel states of matter can emerge.
Under these extreme conditions, Zwierlein and his colleagues were studying the behavior of fermions. A fermion is technically defined as any particle that has an odd half-integer spin, like neutrons, protons, and electrons. In practical terms, this means that fermions are prickly by nature. No two identical fermions can occupy the same quantum state — a property known as the Pauli exclusion principle. For instance, if one fermion spins up, the other must spin down.
Electrons are classic examples of fermions, and their mutual Pauli exclusion is responsible for the structure of atoms and the diversity of the periodic table of elements, along with the stability of all the matter in the universe. Fermions are also any type of atom with an odd number of elementary particles, as these atoms would also naturally repel each other.
Zwierlein’s team happened to be studying fermionic atoms of potassium-40. They cooled a cloud of fermions down to 100 nanokelvins and used a system of lasers to generate an optical lattice in which to trap the atoms. They tuned the conditions so that each well in the lattice trapped a pair of fermions. Initially, they observed that under certain conditions, each pair of fermions appeared to move in sync, like a single molecule.
To probe this vibrational state further, they gave each fermion pair a kick, then took fluorescence images of the atoms in the lattice, and saw that every so often, most squares in the lattice went dark, reflecting pairs bound in a molecule. But as they continued imaging the system, the atoms seemed to reappear, in periodic fashion, indicating that the pairs were oscillating between two quantum vibrational states.
“It’s often in experimental physics that you have some bright signal, and the next moment it goes to hell, to never come back,” Zwierlein says. “Here, it went dark, but then bright again, and repeating. That oscillation shows there is a coherent superposition evolving over time. That was a happy moment.”
“A low hum”
After further imaging and calculations, the physicists confirmed that the fermion pairs were holding a superposition of two vibrational states, simultaneously moving together, like two pendula swinging in sync, and also relative to, or against each other.
“They oscillate between these two states at about 144 hertz,” Hartke notes. “That’s a frequency you could hear, like a low hum.”
The team was able to tune this frequency, and control the vibrational states of the fermion pairs, by three orders of magnitude, by applying and varying a magnetic field, through an effect known as Feshbach resonance.
“It’s like starting with two noninteracting pendula, and by applying a magnetic field, we create a spring between them, and can vary the strength of that spring, slowly pushing the pendula apart,” Zwierlein says.
In this way, they were able to simultaneously manipulate about 400 fermion pairs. They observed that as a group, the qubits maintained a state of superposition for up to 10 seconds, before individual pairs collapsed into one or the other vibrational state.
“We show we have full control over the states of these qubits,” Zwierlein says.
To make a functional quantum computer using vibrating qubits, the team will have to find ways to also control individual fermion pairs — a problem the physicists are already close to solving. The bigger challenge will be finding a way for individual qubits to communicate with each other. For this, Zwierlein has some ideas.
“This is a system where we know we can make two qubits interact,” he says. “There are ways to lower the barrier between pairs, so that they come together, interact, then split again, for about one millisecond. So, there is a clear path toward a two-qubit gate, which is what you would need to make a quantum computer.”
This research was supported, in part, by the National Science Foundation, the Gordon and Betty Moore Foundation, the Vannevar Bush Faculty Fellowship, and the Alexander von Humboldt Foundation. |
A guide for parents and educators on the stages of learning to read that children will go through on their learning to read journey.
Words are everywhere!
So it’s essential that parents and educators provide children with reading experiences daily. We want children to develop a love for reading, and this will only happen if we consider the following key factors:
- positive reading experiences,
- ability to use a variety of techniques for decoding words,
- reading/modelling to your child,
- asking lots of questions,
- celebrate successful moments,
- choosing books that spark interest,
- knowledge of sight words and
- make learning FUN (don’t make it a chore).
There are many different theories and different techniques to teaching reading. Throughout a child’s learning to read experience, the most important thing is to keep a positive attitude.
Reading out loud to children is important. It encourages good expression when they learn to read and a love of books. When reading to a child, there is so much to talk about. Ask the child what the book was about, their favourite character, what things they can see in the picture, what letters or words they can recognise on the page.
From an early age, it’s important to make children aware of the reading process. Always have something around for them to ‘read’ like board books, television guides, magazines, novels. Encourage them to hold the book the right way up and turn the pages. Often children will make up fantastic stories just doing this and looking at the pictures.
The English language uses about 100 common words that children can learn by sight. For everything else, however, children must possess the ability to decode. Knowing the sounds that letters make will help children become competent and fluent readers through decoding.
This leads us to the three main stages of reading in the early years and is how we introduce letters and sounds in the Begin Bright programmes:
Single Sounds Approximate age 3 – 6 years
Single sounds are where children learn the name and sound of the letter and begin to look at simple words like ‘cat’ and identify the beginning, middle and end sound.
For a beginner, this can be very tricky. b, p, d are three of the most commonly confused sounds as they look so similar.
English is a tough language to learn to read and write. At this early stage, children need to practice all their sounds to begin to build words. Children can look at simple words like bed, peg, cat, dog and identify the beginning, middle, and end sounds in this stage. They can also rhyme words and have a simple grasp of comprehension. Children spend their first years learning that the letter ‘c’ makes a ‘c’ sound in cake, but then they discover that it makes ‘sss’ in circle and ‘ch’ in chips. To avoid confusion, explain early on that letters sometimes change the sound they make in words. Knowledge of vowels is also important at this stage.
Blend and End Sounds Approximate age 6 – 7 years
Blending is when you mix/group the letters together, e.g. tr (trip, trace) bl (blue, blink). After children are familiar with all things in stage one, they can move on to blending sounds. In this stage, children learn the common sounds that are made when two or three letters are grouped together. Once they have established this connection, decoding words and reading fluency will become easier.
Double Sounds Approximate age 7 – 9 years
Double sounds are the trickiest ones to learn. There are a lot of them, different letter combinations make the same sound, and the same letters can make different sounds!
e.g. ‘oo’ as in book or ‘oo’ as in moon – ‘ee’ as in see and ‘ea’ as in sea. When learning about doubles with vowel sounds, a great trick is, ‘when two vowels go walking, the first one does the talking (e.g. seat)’.
This is not something that you would think about when reading but can be incredibly confusing to children, so a lot of patience needs to be exercised when trying to explain. The automatic recognition of these double sounds will help children read fluently and decode more easily.
In the first year of school, children will be learning ‘sight words’ and are generally taught to use the ‘look and say’ method. Once children know sounds, it will be easier for them to decode. Depending on the school, teachers expect children to know how to read the list of 100 most frequently used words in our language by the end of their first year at school. It sounds like a lot of words to learn! This is why school readiness is so important to give your children a head start to reading. If children aren’t progressing, ask the school for support – ask questions like ‘does my child need extra support/assistance?’ or even in some cases ‘does my child need a speech pathologist?’
Remember always to encourage children to try! It is better to have a go and get closer than not to try at all. Use the pictures in books to help with children’s reading; they often provide the meaning.
Always praise children’s reading. The English language is a tough one to learn. At the start, it seems like there is so much to remember, and it can often be very overwhelming to children. Praise their efforts for every small achievement they are advancing to the time when they can read without consciously thinking about it. After years of learning and practice, you will feel proud as punch when you see children read themselves!
Register now to receive our free Parents Guide to the three stages of reading with more information on how you can support your child’s reading.
If your child needs extra support or you’d like to give them the best start to school and support their learning to read journey you can find your nearest location by clicking below. |
Possibility and impossibility
We use could to show that something is possible, but not certain:
They could come by car. (= Maybe they will come by car.)
They could be at home. (= Maybe they are at home.)
We use can to make general statements about what is possible:
It can be very cold here in winter. (= It is sometimes very cold here in winter.)
You can easily get lost in this town. (= People often get lost in this town.)
We use can't or cannot to say that something is impossible:
That can't be true.
You cannot be serious.
We use could have to make guesses about the past:
It's ten o'clock. They could have arrived by now.
Where are they? They could have got lost.
We use could to make general statements about the past:
It could be very cold there in winter. (= It was sometimes very cold there in winter.)
You could easily get lost in that town. (= People often got lost in that town.)
We use can't have or couldn't have to say that a past event was impossible:
They know the way here. They can't have got lost!
If Jones was at work until six, he couldn't have done the murder.
We use can and can't to talk about someone's skill or general abilities:
She can speak several languages.
He can swim like a fish.
They can't dance very well.
I can see you.
Help! I can't breathe.
We use could and couldn't to talk about the past:
She could speak several languages.
They couldn't dance very well.
We use could have to say that someone had the ability or opportunity to do something, but did not do it:
She could have learned Swahili, but she didn't want to.
I could have danced all night. [but I didn't]
We use can to ask for permission to do something:
Can I ask a question, please?
Can we go home now?
could is more formal and polite than can:
Could I ask a question please?
Could we go home now?
We use can to give permission:
You can go home now.
You can borrow my pen if you like.
We use can to say that someone has permission to do something:
We can go out whenever we want.
Students can travel for free.
We use can't to refuse permission or say that someone does not have permission:
You can't go home yet.
Students can't travel for free.
We use could you … as a polite way of telling or asking someone to do something:
Could you take a message, please?
Could I have my bill, please?
can is less polite:
Can you take a message, please?
We use can I … to make offers:
Can I help you?
Can I do that for you?
We sometimes say I can ... or I could ... to make an offer:
I can do that for you if you like.
I could give you a lift to the station.
We use could to make suggestions:
We could meet at the weekend.
You could eat out tonight.
Questions and negatives
We make questions by putting the subject after can/could:
|Can I ...?
Could I ...?
|Can you ...?
Could you ...?
The negative form is can't in spoken English and cannot in written English.
We sometimes say cannot, but it is very emphatic.
The negative form of could is couldn't in spoken English and could not in written English.
- can and could: possibility 1
- can and could: possibility 2
- can and could: other uses 1
- can and could: other uses 2 |
Biodegradable polymers are the stuff of legend because they are supposed to answer the world’s plastic problem. But what happens when it reaches a landfill instead of an industrial composting facility? Let’s find out.
With a looming plastic crisis on our hands, the world is turning to biodegradable plastics, especially biodegradable plastic packaging, to arrest the onslaught of polymers that can’t be recycled properly or can’t be recycled at a rate that will reduce plastic’s impact on the environment as a whole.
Compostable plastic is one of the more hopeful developments in the last century, as they help divert some of the waste being brought to landfills. How does biodegradable plastic decompose? Do biodegradable plastic bags break down like banana peels and other kinds of food waste?
Do Biodegradable Bags Decompose in Landfill?
No, biodegradable bags will not simply rot or decompose like other organic materials in a landfill. The reality is that manufacturers can get confusing when marking their products, so the bio-based plastics in your neighborhood may not even be truly compostable.
Putting “environmentally-friendly” on a bag of plastic bags does not automatically mean that those bags will decompose. There are only three classes of biopolymers that will break down properly in the right conditions. Those marked with “biodegradable” or “100% biodegradable” and those marked with “home compostable” or “industrial compostable.”
In the US and the UK, sorting policies are stricter, so polymer-based products are marked more accurately. Sometimes, however, even that effort needs more work. The recycling rate never reaches 100%. There are still gaps in the workflow that gets the recyclable materials to the right facilities.
We can say that it’s the same problem for biopolymers marked with either compostable or biodegradable. There is no method to get all of those plastics back once sold in stores and supermarkets. There is always a portion of it left behind, usually ending up in landfills and, in other moments, in the seas and oceans.
Biodegradable bags are the most ubiquitous because people carry everything in plastic bags. We produce more plastic bags than anything else in the world. Plastic bags will easily outnumber other kinds of products made with any polymer. With this in mind, it’s important that we can reel in our plastic consumption, so we don’t end up with even more plastic bags polluting our waterways and land.
Perhaps, the first big step is understanding that even the highest quality biodegradable or compostable plastic bags will not degrade in landfills. Why? Because they require specific conditions before they can begin to break down. Until those conditions are met, these biopolymers are going to behave pretty much like conventional polymers. What does this mean?
When biopolymers are made, they have to have the same structural and mechanical integrity and durability as classic or traditional polymers. Otherwise, we won’t be able to use them in the same manner as conventional plastics. Therefore, they have to behave like regular plastics when they’re still in use. It gets complicated when the plastic reaches the end of its life, and you now have to dispose of the plastics. Is there a proper sorting method in your city? Will you bring your biodegradable or compostable plastics to a curbside spot where the biodegradable plastics can be deposited and then sorted for industrial composting?
It’s not enough for people to have access to these new biopolymers. There also has to be a system that will take care of the waste material at the end of its life. If not, these biodegradable plastics will end up in landfills like the other plastics we have now, and they’re not going decompose there.
How Long Does Biodegradable Plastic Take to Break Down?
When sorted and properly composted in the right facility, biodegradable and compostable plastics will only take about three to six months to return to their basic states after decomposition. The composting process is not the same as what we do in our backyards, so it doesn’t happen as quickly, and it’s better to call the process by its real name biological treatment.
Biological treatment is science, and it takes some time for the biological treatment to take effect. Once the biological treatment starts, it will take a period of waiting for the bacteria to finally interact with the bioplastics finally. Then that’s when things will start to get drastic. Once the resin’s surface has been breached by the bacteria, moisture, and air, it will begin to break down, and finally, the decomposition begins.
How Long Does It Take Plastic to Degrade in A Landfill?
Degradable plastics can take a few months before they can fully degrade. However, degrading is not the same as decomposition. It’s just physical degradation, where the physical structure melts. The plastic’s chemical integrity remains the same, and that’s why degradable plastics don’t address plastics’ problems. They introduce a new problem to the equation. How do we get rid of the toxic sludge that is left behind by degradable plastics? We must know how to get rid of the byproducts of plastics, too.
If we look at conventional plastics, or those that were developed decades before degradable plastics were researched, then those things will not degrade any time soon. Even organic matter in landfills takes very slow to degrade. Why? Because there’s barely any air in landfills, and there is no air, the aerobic bacterial activity cannot work properly. The breakdown of organic matter requires the help of both anaerobic and aerobic bacteria. If there is no oxygen in the equation, then the breakdown will take place ever slowly. Some scientists have examined biodegradable objects in US landfills, and they’ve found out that stuff thrown out in the 1940s was still intact. We’re talking about hotdogs, corn cobs, and even newspapers. Newspapers remained largely readable after several decades, even though the paper is supposed to break down properly after a few months only. |
Did you know that the body is not able to make vitamin C on its own? That’s why it’s important to include vitamin C-rich foods into your diet. In the body, vitamin C serves many roles: to help form an important protein used to make blood vessels, ligaments, skin and tendons; to help heal wounds and form scar tissue; and to repair and maintain bones, cartilage and teeth. Vitamin C is also a powerful antioxidant that helps block some of the damage caused by free radicals.
There are many fruits and vegetables that contain vitamin C so it’s easy to fit this crucial vitamin into your daily diet. Fruits and vegetables that contain vitamin C include broccoli, Brussels sprouts, cabbage, cantaloupe, cauliflower, collard greens, fennel, grapefruit, green peppers, kale, kiwifruit, mango, oranges, papaya, pineapple, raspberries, spinach, strawberries, sweet potatoes, Swiss chard, tomatoes, watermelon, and winter squash, just to name a few. Take note—the best food sources of vitamin C are uncooked fruits and vegetables. And there are some foods, such as cereals and other foods and beverages that have had vitamin C added to them.
One sign of vitamin C deficiency is weak immune function, including susceptibility to colds and other infections. |
Speaking without masks in confined spaces poses the greatest risk of spreading SARS-CoV-2, the virus that causes Covid-19, to others, according to a study.
The study published in the Journal of Internal Medicine describes how different-sized respiratory droplets emitted while speaking span a continuum of sizes and carry different amounts of virus.
Most concerning are intermediate-sized droplets that remain suspended in the air for minutes and can be transported over considerable distances by convective air currents.
“We’ve all seen some spit droplets flying when people talk but there are thousands more, too small to be seen by the naked eye,” said Adriaan Bax, from the US National Institute of Diabetes and Digestive and Kidney Diseases in Maryland.
“When the water evaporates from such speech-generated, potentially virus-rich droplets, they float in the air for minutes, like smoke, thus putting others at risk,” Bax added.
Since the beginning of the Covid-19 pandemic last year, researchers have argued that Covid-19 was not airborne. However, in May, US Centers for Disease Control and Prevention (CDC) announced that exposure to respiratory fluids — very fine respiratory droplets and aerosol particles — present in the air and which carry viruses are the main reason for contracting Covid-19 infection.
The Indian government also in an advisory stated that aerosol and droplets are key modes of transmission of the virus. It added that the aerosol can travel up to ten metres from the infected person, and that aerosol through the infected person can fall within two metres but can be carried to ten metres through the air.
The advisory said, to prevent it people should continue wearing masks, wear double masks or a N95 mask. Introduction of cross ventilation and exhaust fans will be beneficial in curtailing the spread of the disease, it said. |
Adapted by Joyce McBeth, University of Saskatchewan
from Physical Geology by Steven Earle
Complete this chapter so you can:
- Define, draw, and describe the major features of glaciers
- Explain the differences between continental and alpine glaciation
- Summarize how snow and ice accumulate above a glacier’s equilibrium line and are converted to ice
- Explain how basal sliding and internal flow facilitates the movement of ice from the upper part to the lower part of an alpine glacier
- Describe and identify the various landforms related to alpine glacial erosion, including U-shaped valleys, arêtes, cols, horns, hanging valleys, truncated spurs, drumlins, roche moutonnées, glacial grooves, and striae
- Identify various types of glacial lakes, including tarns, finger lakes, moraine lakes, and kettle lakes
- Describe the nature and origin of lodgement till and ablation till
- Describe the nature and origin of glaciofluvial, glaciolacustrine, and glaciomarine sediments
- Describe the timing and extent of Earth’s past glaciations, going as far back as the early Proterozoic
- Describe the important geological events that led up to the Pleistocene glaciations
- Explain how the Milankovitch orbital variations along with positive climate feedback mechanisms may have controlled the timing of the Pleistocene glaciations
A glacier is a long-lasting (decades or more) body of ice that is large enough to move under its own weight. They are at least tens of metres thick and at least hundreds of metres in extent. About 10% of Earth’s land surface is currently covered with glacial ice, and although the vast majority of this is in Antarctica and Greenland, there are many glaciers in Canada, especially in the mountainous parts of BC, Alberta, and the Yukon, and in the far north (Figure 17.1). At various times during the past million years, glacial ice has been much more extensive, covering at least 30% of the Earth’s land surface at times.
Glaciers currently represent the largest repository of fresh water on Earth (~69% of all fresh water). They are highly sensitive to changes in climate, and in recent decades have been melting rapidly worldwide (Figure 17.2). Although some of the larger glacial masses may still last for several centuries, smaller glaciers, including many in western Canada, may be gone within decades. For mountainous regions, glaciers are an important sources of drinking water. Rapid glacial melting is a troubling issue for western Canadians because glacial ice is an important part of the hydrologic cycle in glaciated regions. Irrigation systems in BC, and across Alberta and Saskatchewan, are replenished by meltwater originating from glaciers in the Coast Range and the Rocky Mountains. |
Tyrannosaurus Rex is the most well-known dinosaur, having inspired several books, films, television shows, and video games. Tyrannosaurus lived up to its reputation as one of history’s most terrifying creatures. Tyrannosaurus possessed 60 teeth, each measuring up to 20cm (8 inches) long, and its bite was roughly three times stronger than a lion’s. Bite marks discovered on the bones of Triceratops and Edmontosaurus prove that Tyrannosaurus could crunch through bone. The bones of Tyrannosaurus prey were discovered in the faeces of the dinosaur.
Tyrannosaurus is perhaps one of the most well-known dinosaurs, and it was one of the last major carnivores before the great extinction 66 million years ago. It wasn’t the biggest, but it was one of the most dangerous predators around.
Tyrannosaurus, like other carnivorous dinosaurs in its family, had a huge skull and a long, heavy tail. Its short, two-fingered arms were roughly the length of a human’s and did not even reach the tip of the nose when stretched. Tyrannosaurus Rex could bite through solid bones with its gigantic fangs, which were up to 18 cm long and curled inwards. Tyrannosaurus tooth was lost, but it grew back within a few weeks. Tyrannosaurus’ relatively large weight most likely prevented it from reaching very high speeds. It was still a successful hunter, but scientists believe it ate carrion as well.
Researchers in the US state of Montana unearthed Tyrannosaurus rex bones in 2003. Because a bone was too huge to be transported by helicopter, it had to be sawn through. The scientists who later investigated the bone were shocked to find traces of blood arteries that had not fully petrified inside the million-year-old fossil. In 2007, researchers led by Mary Schweitzer of North Carolina State University studied the discovery and discovered soft tissue and blood arteries intact within the femur. They were able to isolate the protein collagen, which is an organic component of skin, tendons, and bones, as a result of this.
In 2008, Harvard University in Cambridge researcher Chris Organ and his team discovered that Tyrannosaurus was more closely linked to birds than to other animals. Some amino acid chains, the building blocks of the “primordial protein,” may also be identified. When compared to modern species’ amino acid chains, the sequences of tyrannosaurus most closely resemble those of chicken, newt, and frog. The parallels to chickens, in particular, support the theory that dinosaurs and modern birds are linked.
The following are some of our favourite interesting facts about Tyrannosaurus Rex, which will provide you with the most comprehensive understanding of T-Rex possible, which you can then share with your friends.
1: Tyrannosaurus Rex quick facts:
Name: Tyrannosaurus (Greek for “tyrant lizard”); pronounced tie-RAN-oh-sore-us
When it lived: Late Cretaceous, 90-66 million years ago
Type of dinosaur: Large Theropod
Location: USA, Canada
Habitat: High humidity and semi-tropical temperatures of western North America.
Length/Weight: 12 meters/7000kg
Distinguishing Characteristics: Large head with forward-facing eyes, massive muscular jaws, robust serrated teeth, a powerful tail, and tiny arms.
Named by: Osborn (1905)
2: Why is T. rex the king of dinosaurs?
Tyrannosaurus rex (“king of the tyrannical lizards”), commonly known as “The King of the Dinosaurs,” was a gigantic carnivorous theropod dinosaur that lived between 90 and 66 million years ago. Tyrannosaurus Rex is the most well-known dinosaur. This is largely due to the fact that it was the first enormous carnivorous dinosaur to be discovered, and it was long thought to be the largest ever.
Another factor was that it was most likely the world’s most ferocious meat eater. It was enormous, standing over 40 feet tall with the most strongest head of any dinosaur. It also had the largest teeth of any dinosaur, teeth that were both sharp and cutting edged, as well as massive and robust, capable of crushing bones.
3: When was T. rex discovered?
In 1902, Barnum Brown, an assistant curator at the American Museum of Natural History, found the holotype specimen of T. rex in Montana’s Hell Creek Formation. The holotype is the only example of a new species that is used to give it a name. In the following years, he and his colleagues would uncover numerous more species in the West. Henry Fairfield Osborn, then-museum president, named the dinosaur Tyrannosaurus rex in 1905.
4: How big was T. rex?
Scientists estimate that a Tyrannosaurus rex might have been up to 40 feet long and 12 feet tall based on fossil specimens.
With skin and flesh on its massive bones, T. rex was estimated to weigh between 11,000 and 15,500 pounds (5,000 and 7,000 kg). This is around the same as the largest African elephant.
5: How fast was T. rex?
Dinosaur speeds are typically estimated using fossil trackways. Based on the best-preserved trackways, the most reasonable interpretations suggest a walking speed of 3 to 6 miles per hour. Biomechanics is frequently used to determine running speeds. Researchers look at the muscles and body designs of large living creatures, as well as the stress that running puts on the body.
Scientists believe T. rex was a slow runner, clocking in at around 10 miles (16 kilometres) per hour, or about the same as a typical human runner. According to these experts, T. rex’s size slowed him down. Bones, muscles, and posture all contribute to this.
6: What did T. rex eat?
Teeth are the strongest indicators to dinosaur nutrition, aside from fossilised stomach contents. Carnivorous animals’ teeth are typically sharp, serrated blades that resemble daggers. These teeth aid the animal in both killing and slicing its prey before consuming it. Tyrannosaurus rex ate big chunks of meat rather of chopping or grinding it. T. rex possessed a hinge in the middle of its lower jaw that may have helped absorb some of the shock caused by fighting prey.
7: Where did Tyrannosaurus rex live?
The majority of T. rex fossils have been discovered in the Northwest, in places like Montana and South Dakota. In Alberta, Canada, T. rex fossils have also been discovered.
8: When did T. rex live?
T.rex lived between 90 and 66 million years ago, at the conclusion of the Late Cretaceous period.
The relative placements of fossils in the ground are one method of dating them. Paleontologists are, in effect, peering back in time when they dig deeper into sedimentary rock. Because older layers are buried when sediments transported by wind and water accumulate, the bottom layers in a geological sequence are normally the oldest and the top layers the youngest. Scientists can use the quantity of specific radioactive elements—often radiocarbon or potassium—present in rocks and fossils to estimate when a rock was produced or when an animal died.
9: How many eggs did Tyrannosaurus lay?
Although no T. rex eggs or nests have ever been discovered, other Tyrannosaur relatives’ remains imply that they deposited elongated eggs in batches of 20 or more.
Adult T. rexes may have guarded their nests and fed their young in the same way that birds and crocodile parents do (their closest modern relatives), but there is no concrete evidence of prenatal care.
10: How long did Tyrannosaurus rex live?
Tyrannosaurus rex lived for approximately 28 years. Previous research revealed it went through a growth surge in its adolescence, but scientists didn’t know much about how it evolved from a hatchling to a powerful predator until recently.
In January 2020, researchers discovered that the bones of Nanotyrannus—a smaller tyrannosaur thought to have lived alongside T. rex—were more likely from a young T. rex than from another species. The study suggests that Tyrannosaurus rex’s growth rate fluctuated as it grew older, and that it could slow down its growth when food was scarce, which would be a significant evolutionary benefit.
11: How old is the oldest Tyrannosaurus rex?
The T. rex grew rapidly, reaching adult size as a teenager, and died young, according to growth rings. The oldest specimen that was examined was only 28 years old. Animal bones, like tree trunks, can generate growth rings over time. The number of rings on a specimen indicates its age, while the breadth indicates whether it was still expanding. However, only a few bones have a complete set of growth rings; sadly, the massive limb bones that are best preserved as fossils are not among them.
12: The original name for tyrannosaurus rex was “Manospondylus.”
The first T. rex specimen was discovered by renowned palaeontologist Edward Drinker Cope in 1892, and Cope briefly pondered renaming his discovery Manospondylus gigax, which is Greek for “giant thin vertebrae.” It was up to Henry Fairfield Osborn, the then-president of the American Museum of Natural History, to erect the iconic name Tyrannosaurus rex, the “tyrant lizard king,” following additional stunning fossil discoveries.
13: Other interesting Tyrannosaurus Rex facts:
- Tyrannosaurus is a Greek term that means “tyrant lizard.”
- T. rex Sue was auctioned for US$8.3 million in October 1997, the highest price ever paid for a dinosaur fossil until T. rex Stan was auctioned for US$31.8 million on October 7, 2020.
Sources:Wikipedia, American Museum of Natural History
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How did the Nile shape ancient Egypt Dbq?
The mother Nile, its waters replenished, then flows north and into Egypt. There, the water spills over its banks and covers the low-lying flood plain. For thousands of years, this flooding cycle has provided a seasonal rhythm for the Egyptian people. The flooding cycle determined the planting season for farmers.
How did the Nile shape ancient Egypt?
The Nile River shaped ancient Egypt in that it provided a waterway for trading, a means of defending against enemies, and a water source for agriculture. Each year, the river flooded the land around it. This caused silt deposits to develop and made the land fertile for agriculture.
How did the Nile River influence Egyptian art?
Much Egyptian art was created from materials that were available because of the Nile River. Locally available materials included limestone, which was plentiful in the Nile River valley, as well as sandstone and calcite. These soft materials were easy to carve and were used to create reliefs for temples and statuary.
What is the characteristic of Egyptian art?
Ancient Egyptian architecture, for example, is world famous for the extraordinary Egyptian Pyramids, while other features unique to the art of Ancient Egypt include its writing script based on pictures and symbols (hieroglyphics), and its meticulous hieratic style of painting and stone carving.
What type of art did ancient Egypt have?
It includes paintings, sculptures, drawings on papyrus, faience, jewelry, ivories, architecture, and other art media. It is also very conservative: the art style changed very little over time. Much of the surviving art comes from tombs and monuments, giving more insight into the ancient Egyptian afterlife beliefs.
What is the oldest known piece of art?
Scientists Have Discovered the World’s Oldest Figurative Art: a 40,000-Year-Old Cave Painting of CattleThe world’s oldest figurative art, showing wild cattle, in a Borneo cave, was made at least 40,000 years ago. The world’s oldest figurative art was found in a cave in the Borneo jungle.
How did Egypt influence Greek art?
The Greeks started carving large-scale sculptures out of limestone and marble in the mid-7th century BC. The Greeks also became familiar with Egyptian culture through small objects such as scarabs and amulets imported from Egypt to Greece as souvenirs or exotica.
Did Greek mythology come from Egypt?
Herodotus frequently mentions that the Greeks adopted the names of the gods from Egypt. Herodotus does not mean to suggest that the names of the gods of Greece are actually Egyptian in origin. Linforth argues that Herodotus, when stating this, “wishes to say that the Greeks derived their knowledge of a god from Egypt.”
What did ancient Greece trade with Egypt?
In major Greek cities, people could buy wheat and slaves from Egypt. Slaves were people who were captured, bought and sold. The Greeks also bought textiles, spices and papyrus. This is a type of paper from Egypt made from the papyrus plant.
Did Greece colonize Africa?
Other Greek colonies were founded on the coast of Gaul, on the Cyrenaica peninsula in Africa and also in Egypt. In this burst of colonial expansion cities such as Corinth, Miletus, Megara and Phocaea took the lead.
Is Egypt and Greek the same?
Modern diplomatic relations between the two countries were established after Greece gained its independence in 1821, and are today regarded as cordial….Country comparison.EgyptGreeceArea1,002,450 km2 (387,048 sq mi)131,990 km2 (50,944 sq mi)Population Density97/km2 (250/sq mi)85.3/km2 (221/sq mi)10
Who were slaves in ancient Greece?
The terminology differs: the slave is no longer do-e-ro (doulos) but dmōs. In the Iliad, slaves are mainly women taken as booty of war, while men were either ransomed or killed on the battlefield. In the Odyssey, the slaves also seem to be mostly women. These slaves were servants and sometimes concubines.
Who did the Spartans enslave?
Helot, a state-owned serf of the ancient Spartans. The ethnic origin of helots is uncertain, but they were probably the original inhabitants of Laconia (the area around the Spartan capital) who were reduced to servility after the conquest of their land by the numerically fewer Dorians.
What were Spartan slaves called?
The population of Sparta consisted of three main groups: the Spartans, or Spartiates, who were full citizens; the Helots, or serfs/slaves; and the Perioeci, who were neither slaves nor citizens. The Perioeci, whose name means “dwellers-around,” worked as craftsmen and traders, and built weapons for the Spartans.
Who were slaves in ancient Egypt?
Many slaves who worked for temple estates lived under punitive conditions, but on average the Ancient Egyptian slave led a life similar to a serf. They were capable of negotiating transactions and owning personal property. Chattel and debt slaves were given food but probably not given wages.
When did Egypt ban slavery?
Where did the slaves live in ancient Egypt?
Slaves, usually prisoners of war, were sent to such teams and probably were treated just like the other workers, the Egyptologist believes. We also know that slaves worked in Deir el-Medina, a village of workers who were building the tombs in the Valley of the Kings near Luxor in Upper Egypt.
How many Egyptian slaves were there?
Apparently there were at least 30,000 slaves in Egypt at different times of the nineteenth century, and probably many more. |
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