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Parliamentary democracy was implemented (restored, in fact) in Spain following the death of General Francisco Franco in 1975. Franco had ruled as dictator since 1939 (the end of the Spanish Civil War), his death sparked major political reformation: the greatest change in Spanish politics came in 1978 when a new constitution was created, establishing Spain as a parliamentary monarchy. The Spanish parliament is called Las Cortes Generales and is a bicameral parliament consisting of the Congress of Deputies (El Congreso de Diputados), the Upper and Lower Houses (La Cámara Alta and La Cámara Baja respectively) and the Senate (El Senado). Government and members of the Spanish parliament are chosen by general elections held every four years. The Spanish Prime Minister (el Presidente del Gobierno) responsible to the Cortes is elected by Spanish parliament. Spanish Local government The 1978 constitution led to the creation of autonomous regions. By 1985, 17 nationalities and regions covering all of peninsular Spain, the Canary Islands, and the Balearic Islands had negotiated territorial constitutions with the central government. In 1979, the first autonomous elections were held in the Basque Country and Catalonia, which have the strongest local traditions by virtue of their history and separate languages. Since then, autonomous governments have been created in the remainder of the 17 nationalities and regions. Politics in Spain Politics in Spain is largely contested by two main parties: the PSOE (el Partido Socialista de Obreros Españoles) and the PP (el Partido Popular), however any regional parties are becoming increasingly influential. The PSOE is centre-left and the PP, centre-right. Historically the ideologies of the two parties were more extreme and so further away from eachother on the political continuum. Nowadays there is not a great deal of light between the two. Regional parties like the PNV (el Partido Nacionalista Vasco) in the Basque Country and CiU (Convergencia i Unió) in Catalonia have a significant influence on Spanish politics.
Lithium, the lightest metal, used in batteries and mood-stabilising drugs, is rarer than it should be. Models of the period after the Big Bang explain how it, hydrogen and helium were synthesised in nuclear reactions, before the universe cooled enough for the stars and planets that we see today to come into being. Astronomers though think that about three times as much lithium was produced in that earliest epoch than remains today in the oldest stars in the galaxy, and the difference has proved hard to explain. Now a group of scientists, led by Xiaoting Fu of the International School for Advanced Studies in Trieste, Italy, think they have the answer to this so-called ‘lithium problem’: it was destroyed and re-accumulated by these stars shortly after they were born. The team publish their work in Monthly Notices of the Royal Astronomical Society. In the past astronomers have speculated on what might be responsible for the lithium deficit. Ideas included as yet unknown aspects of particle physics, nuclear physics or even new models of cosmology. Fu’s team instead looked at how much lithium there would have been when a particular subset of the first long-lived stars formed, just a few hundred million years after the Big Bang. These are still around today, so provide astronomers with some insight into the history of the universe and how its composition has changed. The stars have between 50 and 85% of the mass of the Sun, and have lives that are significantly longer, and are thought to remain stable on the so-called ‘main sequence’ for between 15 and 30 billion years. They are poor in most ‘metals’, which in astronomy means every element heavier than helium. The scientists modelled the way that these stars process lithium, starting with the early part of their lives when they are still contracting and heating up under the influence of gravity. In that ‘pre-main sequence’ phase, the new model suggests that there is more mixing in the different layers of these objects. To put this in context, stars have a hot core, where nuclear fusion is converting hydrogen to helium, a cooler outer layer where convection cycles material from above the core to the surface and down again, and a surface where electromagnetic radiation (including light and heat) escapes into space. The new work indicates that in this first phase of their lives, the low-mass stars have an extra mixing ‘overshooting’ at the base of the convection zone, where surface lithium is brought to the hot interior and almost completely destroyed. Pre-main sequence stars are also surrounded by the residual gas and dust from which they formed. This cloud will over time be pulled on to the star, adding lithium to its surface. As the star ages, the convective zone becomes shallower, so material is no longer sent to the core, to some extent offsetting the earlier destruction of lithium. Stars also shine brightly in ultraviolet light, and the ‘radiation pressure’ of this light eventually blows the disk materials away, stopping the star from accumulating more lithium. The stars then enter the main sequence and settle into a long period of stability. When we observe them now, between 10 and 12 billion years later, they show a constant abundance of lithium, which is about one third of the primordial level. Fu comments: “Our work is a completely new approach to the lithium problem. The model not only may explain the loss of lithium in stars, but could also help explain why the Sun has fifty times less lithium than similar stars and why stars with planets have less lithium than stars on their own.” In the next decade new observatories like the European Extremely Large Telescope (E-ELT) under construction in Chile should allow astronomers to look back at the first metal-poor stars as they formed, and confirm the rapid loss of lithium in the early Universe.
How Lasers Work How does a laser work? A laser is one of the few really important applications of quantum mechanics, but like quantum mechanics itself, it is a little hard to understand properly. What a laser has to do is to "invert" the "population" of atoms from it is usual distribution where most of the atoms are in very low energy electronic states. A pump adds energy to put most of the atoms in an excited state, and then a few of the atoms randomly decay, emitting radiation. This decay radiation actually increases the chance that other atoms will decay, and the others decay in synchrony with this radiation, adding to it in intensity while maintaining the phase. By placing mirrors at either end of the region where these atoms are, you can cause the radiation to bounce back and forth many times, greatly multiplying the intensity Click here to return to the Physics Archives Update: June 2012
Experience the magical metamorphosis of the Monarch Butterfly Live! Brought to you by Ashank Singh. About the butterflies: Scientific name: Danaus plexippus During the spring and summer months, the Monarch Butterfly's habitat includes open fields and meadows with milkweed. In the winter months, Monarchs can be found roosting in the eucalyptus groves of Northern California and at high altitude pine tree groves in the Sierra Madre Oriental Mountains of Northeastern Mexico. Monarchs undergo a process called complete metamorphosis, or the complete transformation from an immature form to the adult form. There are four stages in a Monarch’s life cycle. These stages are: egg, caterpillar, chrysalis, and butterfly. Eggs are very tiny and are as small as the tip of a safety pin. Caterpillars have skin that has a yellow and black striped pattern. Fully grown, these caterpillars can be as large as 3 inches. The chrysalis is jade in color with a few gold flakes and measures 1.5 inches. In around 10- 14 days the chrysalis hatches into a beautiful orange and black butterfly. As a butterfly, Monarchs have a wing span of 3- 4 inches. It is in this stage that they migrate nearly 3,000 miles to roost in the forests of Mexico. The diet of a Monarch varies in each stage of its life. As a caterpillar, Monarchs eat the poisonous leaves of milkweed plants (genus asclepias). The cardiac glycosides in the leaves of the plants make them extremely poisonous. Consuming these leaves makes the caterpillars poisonous. This makes Monarchs unpalatable. In the chrysalis stage, the Monarch does not consume anything. It uses the energy gained during the larval stage to grow and sustain itself. The poison gained in the caterpillar stage is never lost. As an adult, Monarchs lack jaws. Therefore the adult butterfly obtains food by the means of a proboscis. The proboscis is like a straw and only allows liquid food into the body. Monarchs like drinking water from puddles, nectar from flowers and juice from fruits. In captivity, they often drink sugar water, and fruit juices. Their migration can start off as far as the southern tip of Canada. Weighing less than an ounce, powered only by nectar and body fat acquired during the caterpillar stage, these butterflies fly hundreds of miles each day. In three months they reach the pine tree groves of Central Mexico or the coastline of California where they roost in large numbers. In the process, these butterflies are sheltered from rain, snow, and hail. When the weather warms and spring arrives, the next generation of Monarchs completes the journey north. This is a ritual followed each year by Monarchs. No one knows how Monarchs perform such a feat. This is a phenomena that baffles scientists till this date. Though current research suggests that Monarchs process celestial information coupled with cues from the electromagnetic field of the Earth, no one knows how these creatures perform such an act consistently year after year. A Monarch's migration is truly one of nature's unsolved mysteries. Despite being such beautiful creatures, Monarchs are under increasing threat. The continued use of pesticides and herbicides is killing Monarchs and milkweed alike. To make matters worse, illegal logging operations in the Sierra Madre mountains are destroying the forests where they roost at an alarming rate. With the hard work of passionate people, the Monarch population has risen. Though not an endangered species, Monarchs are still threatened and need our help. By not using pesticides in our gardens and growing milkweed, we can cherish the magic of Monarchs for generations to come. Basic info about the Camera Stream: Camera Location: Fremont, California, United States Time Zone: PDT
The factor by which the angular diameter of an object is apparently increased when viewed through a telescope, microscope, or other optical instrument. It can be calculated by dividing the focal length of the telescope by the focal length of the eyepiece. The best magnification to use depends on the type of observation and on the seeing conditions. High magnification may be necessary, for example, for separating close double stars or for resolving fine detail on a planet's surface, but it can also be a disadvantage. It results a smaller field of view, a dimmer image with less contrast, and the emphasis of any shortcomings in an instrument or atmospheric disturbances. As a rough guide for the amateur, the practical upper limit to a telescope's magnification is twice the instrument's aperture in millimeters. A lower limit to magnification is set by the size of the exit pupil. When this exceeds the size of the pupil of the eye, light is wasted and the image appears no brighter than if the magnification were increased. Related category OPTICS AND OPTICAL PHENOMENA Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact
Step 1:Question: What are the tectonic boundaries? Quick Google image search for “plate tectonic map”, use Picture Step 2: Answer: Tectonic plate boundaries can be divergent, convergent, or transform. (gesture: Stick out thumbs and move them away from each other, move pointer fingers towards each other, slide palms against each other in opposite directions) Step 3: Explore: Intro video Table on SMART board. Pairs use simulator to predict/analyze plate movements, and fill in chart. When plates move towards each other... When plates move away from each other... When plates move past each other... Step 4: Quick Test (QT) using SMART Response clickers - Convergent boundaries form when plates move towards each other. - Tectonic boundaries are things that move. - A tectonic boundary is a place where two plates interact. - Divergent plates can cause earthquakes. - Transform plates create a large amount of friction. - All tectonic boundaries occur because of the asthenosphere’s movement. - Convergent boundaries can make mountains. - Divergent boundaries make new crust. - A subduction zone happens when one plate goes beneath another plate and becomes part of the mantle. - A collision between two pieces of oceanic crust will form a subduction zone. Step 5: Write/ Critical Thinking: Genius Paragraph Extender sentence with two detail adders giving evidence: Plates move slowly towards each other at a convergent boundary. Two plates come together and crash into each other. Starter blah sentence: Plates move. Paragraph Objective: Write one extender with detail adder that gives evidence Use whiteboard to share sentences with the class. Use oral writing with capital letter gesture (one arm raised up in the air, other arm low to the ground) and period gesture (eeek sound as hand moves forward). Exit Slip: Andes mountains in South America, earthquakes in California, mid-ocean ridge in the Atlantic Ocean
Cartilage is a type of firm, thick, slippery tissue that coats the ends of bones where they meet with other bones to form a joint. Cartilage lines the joint space between bones throughout the body, and it acts as a protective cushion between bones to absorb the stress applied to joints during movement. Cartilage is made up of protein strands called collagen that form a tough, meshlike framework. The mesh is filled with substances that hold water, much like a sponge. When weight is placed on cartilage, water is squeezed out of the mesh. When weight is taken off, the water returns. Cartilage does not contain blood vessels or nerves. Although cartilage is very strong, it can be damaged when a joint is injured. eMedicineHealth Medical Reference from Healthwise To learn more visit Healthwise.org © 1995-2014 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Children with attention and executive skill challenges often have these written expression difficulties: - Spelling errors are mostly phonetic - “Over-applies” spelling rules recently learned - Transition words are used rarely or inconsistently. - Verb tense and noun tense is inconsistent. - May use few or incorrect modifiers - Poor organization limits expression of creative ideas Children with attention challenges benefit from a structured and flexible approach 1. Use technology to help your child prepare written work. Being able to access a computer at school and home for written assignments will allow the support of word processing programs, spell-check, and semantic mapping software. Most children with attention disorders benefit from completing written class work and homework on a computer. The use of computer technology has the potential to increase the quality of their written work. Consider the Parents Guide to Assistive Technology by Marshall H. Raskind, Ph.D. for specific recommendations. 2. Consider teaching your student the structure of the English language as it relates to written expression using the structured teaching tools: - Six Steps to Better Sentences - Four Steps to Planning Better Paragraphs - Three Tips for Writing Better Paragraphs - Purpose + Structure = Better Paragraphs - Structuring for Better Reports - A Flexiture Final Draft Checklist 3. Consider recommendations for accommodating the written expression challenges most often associated with attention disorders. (c) 2010, flexiture, monte w. davenport, ph.d.
Children with ADHD Children with ADHD are just like every other child in this world, and they need to be treated as such. ADHD is the acronym for Attention Deficit Hyperactivity Disorder. Notice that ADHD (Attention Deficit Hyperactivity Disorder) is not a disability, rather a disorder that affects the child's ability to pay attention and stay focused on tasks for sustained amounts of time. Children with ADHD should be treated accordingly and everyone involved with raising the child should understand that some of the behaviors that they see are not the result of the child misbehaving. The behaviors cannot be controlled so caregivers must understand this and be patient when disciplining children with the disorder. The first part of ADHD is the attention deficit. This part of the disorder means that the child usually has trouble paying attention to any one thing for a long period of time. If the child enjoys what he or she is doing than they will stay on task longer, but the amount of time is much less than children without the disorder. The attention deficit can also be noticed when the child seems to be so easily distracted by common things in their environment. Parents and teachers need to know that they need to provide a low stimulus environment for the child if they are really focused on having the child learn. This does occur for all children at sometimes but children with ADHD suffer from this many times each day and this behavior continues for an extended period of the child's life. The second part of ADHD is the hyperactivity. This can often be the most difficult thing to deal with because the child just seems to be unable to sit still or do anything other than being extremely active. The biggest sign of hyperactivity is the constant need to be moving, especially during activities that the child truly enjoys. Children that are hyperactive simply cannot control what their brain is telling them to do, so you must be patient and understand this fact. The best way to treat children with ADHD is by providing them with a very consistent schedule and a living environment that does not create too many distractions. You need to learn what the child loves to do or play and focus much of your child's attention toward that love that they have. As time goes on you should try to explore new opportunities for your child. Some medical professionals also recommend specific drugs that can help to combat the ADHD tendencies that many children have. Putting a child on medication is a big step, so make sure that you are comfortable with the idea and remember to always do what is best for your child.
Lactobacillus is a rod-shaped bacterium that is the part of the normal flora of the human genitourinary and digestive tracts but may cause urinary tract infections, UTI, in individuals with reduced immunity. However, the diagnosis of lactobacillus UTI is often challenging as this bacterium commonly occurs as a contaminant in the urine samples of many patients, especially women. Repeated isolation of the bacteria in the laboratory is essential confirm the diagnosis. The clinical specimen for all suspected cases of UTIs is a clean catch, early morning urine sample. Since the first part of the urine tends to flush out urethral contaminants, a mid-stream urine sample is collected in a screw-capped, sterile plastic bottle. If lactobacilli are isolated from the urine sample, a repeat test is ordered to rule out contamination and to confirm true lactobacillus infection. An article published in the November 1999 issue of "Nephrology Dialysis Transplantation" recommends direct aspiration of the urine sample from the urethra or the suprapubic region using a needle to rule out contamination in such cases. Urinalysis is often the first test that is performed in a doctor's office to check for the presence of UTI and involves three steps. According to MedlinePlus, the first step involves visual examination of the urine sample for color and clarity. This is followed by a preliminary microscopic examination that detects the presence of pus cells, mucus and other substances. The third step is a chemical analysis that involves dipping a special stick coated with chemicals into the urine sample. These chemicals change color when they encounter substances of interest such as glucose or creatinine. If the urinalysis reveals anything suspicious, the patient's sample is sent to the laboratory for further testing. A small amount of the urine sample is placed on a glass slide, stained with dyes such crystal violet and basic fuchsin and observed under the microscope. According to "Mackie and McCartney's Manual of Practical Medical Microbiology," the presence of purple-colored, rod-shaped bacteria provides a preliminary diagnosis of lactobacilli. A small amount of the urine sample is placed on growth medium plates, which consist of gels that promote the growth of the bacteria. The plates are then incubated at 37 degrees Celsius for 18 hours. The presence of bacterial colonies on the plates indicates infection. The colonies are then confirmed to be lactobacilli using an array of biochemical tests such as gas chromatography. In case of lactobacilli and other contaminating commensals, the proof of a UTI requires the demonstration that the bacteria is present in the urine in numbers greater than those likely to result from contamination. Mackie and McCartney's Manual of Practical Medical Microbiology states that the presence of significant number of bacteria in the urine is known as significant bacteriuria and is indicated by the presence of greater than 100,000 bacteria/ml of urine. Antimicrobial assays are performed to identify the antibiotic susceptibility pattern of the strain of lactobacilli that is causing the UTI. A small amount of the bacterial culture is placed on a growth medium plate, and paper discs impregnated with antibiotics are placed on it. The plates are then incubated. The absence of growth around a disc indicates that the lactobacilli are susceptible to that particular antibiotic.
1. The problem statement, all variables and given/known data A 1.5 kg mass tied to the roof rotates with constant speed in a horizontal circle. The string makes an angle of 30 deg to the vertical. a) determine the velocity , the centripetal acceleration and the centripetal force on the mass. b) determine the tension in the string. c) say the mass is given a push so that now the mass rotates with a constant velocity of 9.4 m/s . Determine the angle the string makes with the vertical , the centripetal force on the mass and the tension in the string. 2. Relevant equations ∑Fradial = TsinΘ = mv2/R ∑Fy = TcosΘ - mg = 0 3. The attempt at a solution To solve part a: First I found my R by, R = LsinΘ = 1.5sin30° = .75m Second my T by, T= mg/cosΘ = 1.59.8/cos30° = 16.97 N Now I find my velocity by, V= sqrt((RTsinΘ)/m)) = sqrt((.7516.97sin30°)/1.5) = 2.06 m/s the centripetal acceleration, v2/R = a a = TsinΘ/m = 16.97sin30°/1.5 = 5.66 m/s2 for part b I already found my tension to be 17N. Part C is where I am having trouble, how can i find the angle Θ with the new constant velocity if im not given a radius or tension?
In the year of 1775, tension between Britain and North America rose signiﬁcantly, especially with the suppressing acts and the beginning battles of the revolution leading up to the rebellion. This created many clashing point of views such as the loyalist, who sought the reconciliation with the mother country, and the patriots, which supported the ﬁght for their independence. Both these views are argued in the documents Daniel Leonard Deplores Rebellion (1775) and Patrick Henry Demands Boldness (1775), however the points made in Henry’s speech affected the minds of the majority and led to the American Revolution. During this crucial year, many loyalist, such as Daniel Leonard, felt we were ﬁghting a lost cause and that the war was over before it had begun. Daniel Leonard expresses these points and more in his appeal to his countrymen (Daniel Leonard Deplores Rebellion), in which he points out how we, the colonies, are at a disadvantage going up against well-armed Britain. Leonard ﬁrst addresses the overwhelming military experience that the british ofﬁcers and soldiers have over the colonial militia. With this reference to the “militia unused to service, impatient of command, and destitute of resources” (Leonard) he makes the colonial force seem very small in the huge shadow of the highly talented and decorated ofﬁcers and soldiers of the british army. He also reminds the colonist that if, by any small chance, they defeat the large number of british troops in Boston, they would still have to deal with the coastal reinforcements. Through the demoralization of the colonial army, he alludes to the un-uniﬁed quality of the thirteen colonies when he says “Can your ofﬁcers depend upon the privates, or the privates upon the ofﬁcers”. This also is a reference to the suspicion that the colonies had amongst themselves, which adds to the disadvantages of the colonies. This appeal was meant for everyone to hear and to analyze the...
When designing curriculum for three-year-olds through kindergarteners, the unique characteristics of young, gifted children must be carefully considered. Combining several models of curriculum has provided the opportunity to create and develop curriculum that encourages children to be actively involved in constructing the course of study; to integrate disciplines; and to include critical thinking, problem finding, problem solving, evaluation, and creativity. The philosophy of Ricks Center's Early Childhood program incorporates the ideals of the Project Approach, Integrated Curriculum Model, emergent curriculum, and Reggio Emilia. Teaching is based on projects taken from the ideas and interests of the children themselves. Teacher-provided or natural provocations lead to studies that challenge, encourage, and develop the children's prior knowledge and beliefs about the topic of study. These topic studies are integrated with core content areas and often lead to exciting projects. These projects are unique in that they encompass a small group of children rather than the whole class. The students' evolving understandings of a topic direct the content of the project. These projects develop the language, literacy, scientific, mathematical, and social knowledge of the children in an integrated and natural way. Projects work better in small groups because they foster the collaboration of ideas, dialogue, and problem solving in a more organized and controlled way. Learning in the classroom is enhanced by specialist teachers who join the children several times per week to teach Spanish, music, physical education, art, and beginning in Kindergarten, Latin. Watch this video to see an example of a previous class project!
This collection of brief examples from NASA show how math and science topics taught in K-12 classes can be used in interesting settings, including every day life. The examples are written primarily by scientists, engineers, and other content experts having practical experience with the material. In this activity for grades 6-12, students design a seawall to protect a major coastal highway from erosion by ocean waves and address these questions: Erosion–can you fight it? How much energy is involved with waves and erosion? Can humans stop erosion of the shoreline? Should we? Is it cost effective? This lesson for students in grades 5 through 12 explores how computerized barcoding has simplified distributing and pricing of products. Students learn about encoding and decoding, the barcoding system, and how a mathematical formula is embedded in barcoding to safeguard against errors. They use websites to identify product barcodes, test codes from everyday products, and work as an engineering team to come up with the next generation of information embedding systems.
Polar mesospheric clouds can be seen from both the Earth’s surface and in orbit by astronauts aboard the International Space Station (ISS). The clouds are also called noctilucent, or “night-shining,” clouds because they are usually seen at twilight. When the Sun sets below the horizon and the Earth’s surface gets dark, these clouds are still briefly illuminated by sunlight. Occasionally the space station’s high-altitude orbital track becomes nearly parallel to the Earth’s terminator (the day/night line) for a time, allowing polar mesospheric clouds to be visible to the crew at times other than the usual twilight. This unusual astronaut photograph shows polar mesospheric clouds illuminated by the rising, rather than setting Sun. Low clouds on the horizon appear yellow and orange, while higher clouds and aerosols (particles like dust and pollution) are illuminated a brilliant white. Polar mesospheric clouds appear as light blue ribbons extending across the top of the image. These clouds typically occur at high latitudes of both the Northern and Southern Hemispheres, and high altitudes (76–85 kilometres, near the boundary between the mesosphere and thermosphere atmospheric layers). The ISS was located over the Greek island of Kos in the Aegean Sea (near the south-western coastline of Turkey) when the image was taken at approximately midnight local time. The ISS was tracking north-eastward, nearly parallel to the terminator, making it possible to observe an apparent “sunrise” almost due north. Earlier this year, a similarly unusual alignment of the ISS orbit track, the terminator position, and the seasonal position of the Earth in its orbit around the Sun allowed astronauts to capture striking imagery of polar mesospheric clouds over the Southern Hemisphere. Astronaut photograph provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre. Text adapted from information issued by William L. Stefanov and Michael Trenchard, NASA-JSC.
“Individualized Learning” has become a commonly used buzzword in education. But what exactly is “Individualized Learning” and how is it relevant to the day-to-day classroom? Individualized learning can be described as the process of learning within the classroom that allows individual students to progress through classroom material at their own pace and typically through their own methods. Often times, this means students are self-directed and have different means of accomplishing learning goals based on individual abilities, preferences and learning needs. This does not mean that standards or curriculum are different for each student. Instead, individualized learning simply takes a student’s individual learning style and needs into account when planning activities necessary for the student to learn the required/state-mandated material in a way that best suites them as an individual and unique learner. To better understand the buzzword, I created this remix of “individualized learning” with a variant audience in mind. My intentions are that people of all different walks of life (whether teachers or not) can understand the meaning of individualized learning through my one-minute remix. Because my audience is not simply aimed at teachers or teacher-candidates, I thought it best to incorporate both video of students interacting in individualized learning while an experienced adult audibly explains the process, as well as, video that explains the concept through appropriate written text and engaging, but subtle musical accompaniment. To begin my process, I searched for a main video to use as my inspiration of the buzzword, “individualized learning”. I chose to use the “Personalized Learning” video (reference found below) as the outline for my remix project. It seemed to me that parts of this video accurately described individualized learning while other parts did not. So, to begin my remix video, I found a video of a woman relaying the definition of individualized while visually displaying the definition in text. After the definition portion, the remix continues with subsequent contrasting examples of a traditional classroom (which most viewers are likely to be familiar with) vs. a classroom incorporating individualized learning. Because I wanted my viewers to see an individualized learning classroom in action, I chose to incorporate two portions of an Edutopia video. In between the two portions, my original “Personalized Learning” video displays examples of the type of learning and activities learners are to experience when participating individualized learning. While these examples are displayed, a textbox appears to the Twitter hashtag “#individualizedlearning” encouraging viewers to engage in further learning and research of the buzzword. At the end of the video, I also incorporate two web addresses for viewers to read more on the topic. Although my original “Personal Learning” video includes audio, I found the music to be too-fast paced and not conducive to reading text and absorbing information. For that reason, I muted the original audio and added “Hover II” by Andrew Bird as the background audio for my remix. Watch my remix of “individualized learning” here: Bird, A. (2014). Hover II. On SoundCloud. Retrieved from Blossom, A. (2011). Photos 1, 2, 3 and 4. Edutopia. (2010, May 5). Differentiated instruction ignites elementary school learning.YouTube. Retrieved from https://www.youtube.com/watchv=AqepSNNjowU&feature=youtube_gdata Office of Ed Tech. (2012, February 4). Personalized learning. YouTube Retrieved from https://www.youtube.com/watch?v=mC4_ZnxeY3g Spencer, J. (2012, June 9). Personalized learning video. YouTube. Retrieved from https://www.youtube.com/watch?v=YKRV2lXx3dI
Qualitative Analysis on Compound X in order to identify cations and anions present Aim / Objective: To perform qualitative analysis tests on compound X in order to identify cations and anions present. Qualitative analysis is a technique that is used to separate and detect cations and anions in a sample. Anions are atoms or groups of atoms that have gained an electron or electrons. The atoms that form ions most easily are the Group 17 or VII atoms, also called halides: Fluorine (F), Chlorine (Cl), Bromine (Br) and Iodine (I). These form anions with a -1 charge. Oxygen (O), Sulphur (S), Nitrogen (N) and Phosphorus (P) also form anions. Most anions are composed from multiple atoms, and are called polyatomic ions. Cations are atoms that have lost an electron to become positively charged. For example: Sodium (Na) has one valence electron, one electron in its outer energy level, so it tends to lose one electron, and to become an ion with a +1 charge Bunsen burner, red litmus paper, blue litmus paper, distilled water, test tube rack, test tubes, glass stirring rod, metal test tube holder, dilute nitric acid (HNO3), sodium hydroxide (NaOH), potassium iodide (KI), barium chloride (BaCl2), ammonia solution, lead nitrate (Pb(NO3)2), silver nitrate (AgNO3), dilute hydrochloric acid (HCl), splint, dropper, compound X. Method / Procedure: - Heat solid compound X in a dry test tube. - Test the gas evolved with red and blue litmus paper and a glowing splint. - Record the observations. - To a solution of compound X in a test tube add distilled water and dilute HNO3, then add AgNO3 and note observations. - In a test tube mix solution X with distilled water, then add dilute HNO3 and BaCl2 to the mixture. Record the observations. - In a test tube mix solution X with distilled water and heat the test tube moderately. Add dilute HNO3 and Pb(NO3) to the heated mixture. Record the observations. - Mix a small portion of solution X with distilled water in a test tube. Use a dropper to add NaOH in excess to the mixture and heat test tube moderately. Record your observations. - Mix a small portion of solution X with distilled water in a test tube. Add excess ammonia to the mixture and note the results. - Half fill a test tube with solution X and add KI(aq). Record the observations. - Half fill a test tube with solution X, add NaOH(aq) and heat the test tube moderately. Dip the glass stirring rod with the mixture in a beaker of HCl. Test the gas evolved with litmus paper. Record the observations. - Tabulate results - The cations present In compound X were Al3+ and NH4+ - The anions present were SO42- and Cl–
A glacier isn’t the kind of thing you’d expect to get away from you. After all, only the world’s fastest-flowing glaciers can match a snail’s pace. But we know it’s possible for glaciers to have tipping points that, once crossed, result in an unstoppable change. Once unstable, they can lose a lot of ice before finding another stable configuration. Looking back through the history of the Antarctic ice sheets, we know that they have been susceptible to warming in the past. The West Antarctic Ice Sheet is especially vulnerable because a great deal of the continent beneath it is below sea level. If the ice shrinks back from the higher elevation areas, the entire ice sheet can collapse, as it may have done several times in the last million years. Some of the West Antarctic glaciers that prevent this collapse have behaved dynamically in the recent past—and, as we saw this week, there’s evidence that we may be committed to seeing a repeat performance. The amount of ice present there today could raise global sea level roughly several meters if it all melted. But across the continent, the East Antarctic Ice Sheet is much larger, holding the equivalent of 55 meters of sea level rise as ice. Fortunately, it’s perched securely above sea level. Researchers are less concerned with the potential for tipping points there. There are, however, exceptions. Some East Antarctic glaciers have melted back considerably in the past. The key is to figure out how much ice they can lose and how fast they can lose it.
Scientists at NASA’s Langley Research Center in Hampton, Va., have successfully recreated the Northern Lights, Earth’s most beautiful light show, combining all of the necessary ingredients, such as a magnetic field, charged particles and a sphere. The reenactment of Earth’s Northern Lights, also known as the aurora borealis, is generated by a device called “Planeterrella,” a spinoff of an experiment from the 19th century called the “Terrella,” which first demonstrated the glowing result of electrically-charged particles mixing with a magnetic field. “It recreates the atmosphere of the Earth at 80 km in altitude when an aurora is occurring,” Guillaume Gronoff, a research scientist at NASA’s Langley Research Center, said in a statement. “The aurora is created when particles, originally from the sun, precipitate into the atmosphere.” Auroras are most commonly pale green and pink in color but shades of red, yellow, green, blue and violet also have been reported. The phenomenon is called as 'aurora borealis' in the northern hemisphere and 'aurora australis' in the southern hemisphere. NASA's scientists have upgraded the old “Terrella” by adding several spheres, which allows them to recreate the auroral ovals that occur on Earth and on several other planets. Scientists said they can also simulate the auroras on Neptune and Uranus, when their magnetic fields are directly pointing toward the sun. A Planeterrella machine is primarily used for demonstrating to others how each variable interacts to create an aurora. Although there are approximately 10 other Planeterrella machines in Europe, the one at Langley is among the first in the U.S., NASA said. Gronoff, who led the creation of the Planeterrella, said also that the experiment in question is only an illustration as more complex phenomena are occurring in the magnetospheres of planets. According to him, there are various gases on each planet that can create different color effects within auroras. “The Planeterrella can help teach students about solar wind, how electrically charged particles follow the magnetic field and the exciting space missions NASA is launching to space to study these processes,” said Gronoff, who is planning to use a few extra magnets and some carbon dioxide to simulate the aurora on Mars. A diehard lover of photography, Kukil Bora started his career as a Web journalist with a Bangalore-based media firm called “SiliconIndia” in 2010. After working there for a...
Well, destructors are mainly used to de-allocate memory that was allocated to the object by constructor or cleanup of object members. They are not compulsory, that is you have should have it with every constructor. Perhaps you use it as I mentions when you dynamically allocate memory. Destructors are called after the object passes out of scope or is explicitly deleted. As mentioned, destructors are for freeing resources when an object is being deleted. If the object only uses non-dynamically assigned resources, the destructor will do nothing (this is also the default if you don't explicitly code one). If you do use dynamic allocation for any member data, those need to be freed in the destructor or eles you'll have memory leaks - the default doesn't work here. As to why it uses the ~, well, I guess that was the decision of the guy who wrote C++. My guess is that the ~ (two's complement) of the constuctor is the destructor, but that's just what my tired brain is making up... :p >Why destructor with ~ is used in cplus-plus coding for every constructor? ~ is the complement operator in C++, and a destructor is the complement of a constructor. The creator of the language admits that this may have been "overly clever", and I agree thoroughly, but at this point there's nothing we can do about it. For questions like that about the how and why of C++'s design, there's a book by the creator called "The Design and Evolution of C++".
Types of Eating Disorders The eating disorder not otherwise specified (EDNOS) category is for eating disorders that do not meet the criteria for any specific, formally identified eating disorder. In EDNOS, individuals engage in some form of abnormal eating but do not exhibit the specific symptoms required to diagnose an eating disorder. For instance, an individual with EDNOS may meet all the criteria of anorexia nervosa but manage to maintain normal weight, while someone else may engage in purging behavior with less frequency or intensity than a person who has been diagnosed with bulimia. Far more common and widespread than defined eating disorders are atypical eating disorders, or disordered eating. Disordered eating refers to troublesome eating behaviors, such as restrictive dieting, bingeing, or purging, which occur less frequently or are less severe than those required to meet the full criteria for the diagnosis of an eating disorder. Disordered eating can be changes in eating patterns that occur in relation to a stressful event, an illness, personal appearance, or in preparation for athletic competition. The 1997 Youth Risk Behavior Surveillance Study found that over 4 percent of students nationwide had taken laxatives, diet pills, or had vomited -- either to lose weight or to keep from gaining weight. While disordered eating can lead to weight loss or weight gain and to certain nutritional problems, it rarely requires in-depth professional attention. On the other hand, disordered eating may develop into an eating disorder. If disordered eating becomes sustained, distressing, or begins to interfere with everyday activities, it may require professional evaluation.
HTML hr tag HTML <hr> tag is used to specify a paragraph-level thematic break in HTML document. It is used when you abruptly change your topic in your HTML document. It draw a horizontal line between them. It is also called a Horizontal Rule in HTML. HTML hr tagTest it Now HTML is a language for describing web pages. HR tag is used to draw a horizontal line within the texts to separate content. HR tag in HTML 4.01 and HTML5? In HTML 4.01, the <hr> tag represents a horizontal rule while in HTML 5, it defines a thematic break. CSS is used in HTML5 instead of layout attributes. HR tag in HTML and XHTML In HTML <hr> tag need not to be closed whereas <hr> tag must be properly closed in XHTML.
The Reading Like a Historian curriculum engages students in historical inquiry. Each lesson revolves around a central historical question and features a set of primary documents designed for groups of students with a range of reading skills. This curriculum teaches students how to investigate historical questions by employing reading strategies such as sourcing, contextualizing, corroborating, and close reading. Instead of memorizing historical facts, students evaluate the trustworthiness of multiple perspectives on historical issues and learn to make historical claims backed by documentary evidence. To learn more about how to use Reading Like a Historian lessons, watch these videos about how teachers use these materials in their classrooms.
Mechanisms of heat transfer in paper Heat can transfer through paper thickness by conduction, convection and radiation. Thermal conduction is the diffusion-like transfer of energy. The basic mechanism is the exchange of energy, in gases and liquids, say, in molecular collisions from more energetic particles to less energetic ones by random collisions. In solids, conduction can result from the interaction of atoms in the form of lattice vibrations called phonons 1. The following rate equation governs heat conduction in one dimension: where q is the rate of energy transfer across unit area, λ thermal conductivity, and The minus sign indicates that heat flows in the direction of decreasing temperature. Dry paper is a poor thermal conductor. This is because the air-filled pores have low conductivity as such, and that of the three-dimensional fibre network reflects the low thermal conductivity of fibres and the tortuous, disordered structure. The heat conductivity problem in paper is related to that of, say, water vapour diffusion: the former takes place in the fibres, and the second in the pore space, but mathematically they are close. At interfaces between two bodies, the rate of heat transfer decreases due to thermal contact resistance that causes the temperature drop shown in Figure 1. Thermal contact resistance is due to surface roughness that reduces the microscopic contact area. Pressure reduces contact resistance. For most materials, 700 kPa is sufficient to remove contact resistance completely 2. When paper is pressed against a hot cylinder, the apparent contact resistance may be less sensitive to pressure because of convective and radiative heat transfer. Figure 1. Temperature distribution at the interface of two materials showing perfect contact (a) and the temperature drop at the interface in the case of a finite contact resistance (b) 2. Convection is a mode where moving fluid carries heat. A good example of convection is a liquid moving on a heated plate. The equation for convective heat transfer is the following: where h is the convection heat transfer coefficient, and Ts, Tinf the surface and fluid temperatures, respectively. The coefficient h depends on the fluid and surface properties, flow conditions, geometry, etc. Convective heat transfer is a much more effective mechanism of heat transfer than conduction. For paper, the evaporation and re-condensation of water vapour is an effective mechanism of convective heat transfer (/LINK: 03.09.07 Moisture and fluid transport/). The evaporated molecules take energy from warm areas and release it to cooler areas in condensation. Because of the porous nature of paper, convection is important if there is enough moisture available. The diffusion of water vapour will then significantly increase the heat transfer rate above the pure conduction along fibres. Because of the effects of water vapour, measurement of the thermal conductivity of paper gives an apparent thermal conductivity that combines conduction and convection 3, where λ is the “true” thermal conductivity without convection, l the evaporation enthalpy of adsorbed water, εb the effective diffusion resistance coefficient, Mw the mole mass of water, R the gas constant, Dwa the water vapour diffusion coefficient, and pw the vapour pressure. Figure 2 shows the true thermal conductivity, λ, and apparent conductivity, λa, calculated as a function of moisture content at two different temperatures. At low moisture contents, λa increases dramatically because of water vapour convection. At high moisture contents, the vapour flux decreases from collisions between water molecules, and λa declines. Wet paper has no room for water vapour convection. Then λa is entirely due to actual thermal conduction. Figure 2. Calculated apparent thermal conductivity, λa, and ordinary thermal conductivity, λ, of newsprint as a function of moisture content at two temperatures 3. Any material at a finite temperature emits thermal blackbody radiation. Photons emitted in electronic transitions carry the energy. Their wavelength distribution depends on the material and its temperature. The maximum thermal radiation shifts to shorter wavelengths as temperature increases. At room temperature, thermal radiation is in the IR range. It becomes visible when temperature increases above 800 K. The net heat flux is the following: where ε is the emissivity of the material, σ the Stefan-Boltzmann constant, and Ts, Tsur the temperatures of the surface and its surroundings, respectively. Unlike conduction and convection, thermal radiation does not require any intervening medium for heat transfer. The transfer of thermal energy by radiation is most effective in a vacuum. At all relevant temperatures, heat transfer by radiation is negligible inside paper. In some applications such as drying of coatings and toner fusion in electrophotography, paper is heated with IR radiation. IR radiation can penetrate paper effectively and provide uniform heating of the contained water. In paper cooling, thermal radiation needs to be considered even at normal temperatures 4.
NASA – An international team led by astronomers from the Instituto de Astrofisica de Canarias (IAC) and La Laguna University (ULL) has just released the first analysis of the observations of the Abell 2744 cluster of galaxies, a coordinated program of the Hubble and Spitzer space telescopes. They have discovered one of the most distant galaxies known to date, which clearly shows the potential of the multi-year Frontier Fields project. The project uses a phenomenon called “gravitational lensing” where select foreground galaxy clusters amplify the faint light from far-more-distant background objects. By combining Hubble and Spitzer data, these astrophysicists have determined the properties of this young galaxy with a better precision than previous studies of other samples at similar cosmic epochs. This galaxy, named Abell2744_Y1, is about 30 times smaller than our galaxy, the Milky Way, but is producing at least 10 times more stars. From Earth, this galaxy is seen as it was 650 million years after the big bang. It is one of the brightest galaxies discovered at such a lookback time, say researchers. This study provides new constraints on the density and properties of the galaxies in the early universe. These results are accepted for publication in the scientific journal Astronomy and Astrophysics Letters. In addition to the Instituto de Astrofisica de Canarias (IAC) and La Laguna University (ULL), the team is composed of researchers from France (Institut de Recherche en Astrophysique et Planétologie and Centre de Recherche Astrophysique de Lyon), Switzerland (Geneva University and Ecole Polytechnique Federal de Lausanne), and the United States (University of Arizona). For more information about these results, visit: http://www.iac.es/divulgacion.php?op1=16&id=836&lang=en .
ALL PRICES SLASHED FOR DURATION OF COVID-19 DISTANCE TEACHING Materials to teach history, economics, geography and civics. All children deserve to learn about history, economics, geography and civics. With the Every Student Succeeds Act, it is also a requirement. These lessons break down complex ideas into their simplest form. Using best practices for instruction, you are provided with a lesson plan, book, extra activities, visuals and assessments which allow your students to gain and retain important social studies lessons. Students with significant cognitive disabilities, difficulties attending and/or interfering behaviors can all learn key social studies concepts when given the necessary instruction, supports, and enthusiasm of the teacher! Try your first unit for FREE by clicking on the link at the right (Let’s Learn About Maps!). Enjoy! Sign up for our newsletter to find out when new material is added.
Airbag simulators are devices used to simulate the deployment of an airbag in a vehicle during testing or training. These simulators are designed to mimic the impact of a collision and activate the vehicle's airbag system without actually causing physical damage or deploying a real airbag. Airbag simulators are commonly used by automotive engineers, safety experts, and vehicle manufacturers to test the effectiveness of airbag systems and to assess the safety of vehicles in different collision scenarios. By simulating the deployment of an airbag, engineers can evaluate the performance of the system and make any necessary adjustments or improvements to enhance its safety and effectiveness. Airbag simulators can also be used for training purposes, such as teaching mechanics or emergency responders how to properly handle a vehicle's airbag system. By simulating the deployment of an airbag, trainees can learn how to safely and effectively work with the system without risking injury or damage to the vehicle. Overall, airbag simulators are an important tool for testing and improving the safety of airbag systems, as well as for training personnel to work with these critical safety devices.
Our ancestors had extensive knowledge of fungi and multiple uses for a number of them. The uses include for kai and rongoā, tā moko and as a tinder to start fires. Fungi for tattooing Our ancestors found different ways to make colour for tattooing. Black is an important colour, and one of the ways to make black was using a fungus. But the special fungus used, called āwheto (Ophiocordyceps robertsii), is light brown not black and is not often seen today. Somehow, our clever ancestors learned where it lives and collected lots of it. To get the black colour, they burnt it. Unlike wood that turns into grey ash when burnt, āwheto becomes black and can then be ground up into a black powder. This powder was mixed with bird fat to make the black colour for tattooing. Āwheto is a very different kind of fungus from a mushroom, and is different from all other fungi used by our ancestors. It needs an insect as its food, but not just any insect. Only the large caterpillars of two kinds of native moth are the food that āwheto needs to grow. So how does āwheto, that can’t move, find these special two kinds of caterpillar? It only happens by luck or, if you are the caterpillar, by bad luck! Āwheto makes many tiny fungal spores so that one might be eaten by a caterpillar, maybe along with some leaves, or one might become stuck to its body. Āwheto spores somehow know when they have found a caterpillar and they start to grow using the caterpillar’s insides as its food. You might guess what happens to the caterpillar! This kind of caterpillar lives in a burrow in the soil when it’s not feeding, with its head up and tail down, but it seems to also go there when not feeling well. When the fungus feeds on the body of the caterpillar, the dead caterpillar doesn’t become soft and rot but instead becomes hard – rather like a human mummy. To make its spores, the fungus needs to grow out of the caterpillar and spread its spores above the soil. Somehow, the fungus knows that the shortest way above ground is from the head of the caterpillar, so it always starts growing out from there. It forms a straight stick-like fruiting body that grows up out of the soil and into the air. At its tip, spores are formed. So what do you look for when trying to find āwheto? Simply a small brown stick coming out of the soil with a slightly pointed tip. If you are lucky enough to find it and carefully dig down into the soil, you will find the hard dead body of the caterpillar. Both the caterpillar mummy and fungus fruitbody were collected by our ancestors. But how did they find so many to use for tattooing? Fungi for fire carrying The pūtawa fungus feeds on the wood of living beech trees in Tāne-mahuta. Its fruitbodies are bracket shaped and often form high up on trunks. They grow quickly to a large size but only last a few weeks to months before becoming old and falling. When collected on the ground, they need to be dried out before they can be used. Pūtawa was important as tinder – to help start a fire or as a way of carrying fire. When lit, a piece of the dried fruitbody can smoulder for a long time without bursting into flame, so it could be partly buried during the day and lit at night or carried until needed. It could also be used as a torch at night because it burns for a long time. Pūtawa also occurs in Australia where Aborigines used it for this same purpose. For medical use, pūtawa was cut into flexible strips and used to surround and protect wounds. A hole larger than the wound was cut in the strip, and the pūtawa tied in place as a protective pad. Tōtara is a tree of great importance including for building waka and for carving. Kaikākā refers to tōtara heartwood in the centre of old trees that has been decayed by one kind of fungus. The fungus, Inonotus lloydii, rots parts of the wood to form narrow honeycomb-like pockets, giving rise to an attractive effect in carvings. The decay weakens the affected wood and reduces its value for waka or building, but kaikākā wood can still be used for carvings and for fence posts. When reproducing, the fungus forms bracket-shaped fruitbodies on tōtara trunks. Observation in the beech forest Next time you are in a beech forest, look on the ground near the base of trees in case you find a fallen fruitbody of the pūtawa or puku tawai. They can be quite large and are often white and wet. They were dried thoroughly before being used as firelighters. At the marae or museum Look out for examples of carved tōtara wood, maybe in the wharenui, that has a honeycomb-like pattern - caused by a wood decay fungus when the tree was alive. Does the kaikākā enhance the carving? Students can test their knowledge of Māori knowledge and uses of fungi in this online or paper-based quiz. Dr Rebekah Fuller (Te Rarawa) completed a master’s degree looking at traditional Māori knowledge of New Zealand fungi. Hear about Rebekah’s research on fungi. Explore Mahinga kai to find out about other important species. This resource has been adapted from Ngā Hekaheka o Aotearoa, a science/pūtaiao guide for teachers written by Dr Peter Buchanan, Manaaki Whenua – Landcare Research; Dr Georgina Stewart, Te Kura Mātauranga School of Education, AUT University; and Hēni Jacob. These resources have been written from a Māori world view. The Science Learning Hub would like to acknowledge Manaaki Whenua – Landcare Research and the writers for their permission and help to adapt this publication for the web. An electronic version of this teacher guidebook is available to download from Huia Publishers.
Latin America is the part of the Americas that comprises regions where Romance languages that derive from Latin, e.g. Spanish, Portuguese and French, are spoken predominantly. The United Nations has played a role in defining the region, establishing a geoscheme for the Americas, which divides the region geographically into North America, Central America, South America and the Caribbean. The United Nations Economic Commission for Latin America and the Caribbean (ECLAC), founded in 1948 and initially called the Economic Commission for Latin America (ECLA), consisted of Argentina, Bolivia, Colombia, Costa Rica, Cuba, Chile, Dominica, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Paraguay, Peru, Uruguay and Venezuela. They also included the establishment of 1948 Canada, France, the Netherlands, the United Kingdom of Great Britain and the United States. Later on, former colonial powers Spain (197) and Portugal (198) obtained membership. In addition to these countries, other nations that were not colonial powers in the region but had immigrant populations joined ECLAC such as Italy (1990), Germany (200), Japan (200), South Korea (200), Norway (201) and Turkey (201). The Association for Latin American Studies was founded in 1966 and its membership is open to anyone interested in Latin American studies. The origin of the term Latin America is still debated today. It was created in the 19th century after the political independence of countries from Spanish and Portuguese empires. It also became popular in France during Napoleon III's reign as part of his attempt to create a French empire in the Americas. Research has shown that the idea of a part of the Americas having a linguistic and cultural affinity with Romance cultures dates back to 1830s when Frenchman Saint-Simonian Michel Chevalier postulated that part of the Americas was inhabited by people of Latin race and could therefore ally itself with Latin Europe in a struggle with Teutonic Europe, Anglo-Saxon America and Slavic Europe. The distinction between Latin America and Anglo-America is based on predominant languages spoken in each region; Romance language in Latin America and English-speaking cultures in Anglo-America. Neither area is culturally or linguistically homogeneous; for example in substantial parts of Latin America indigenous languages are still spoken today. The oldest known human settlement in this region was identified in Monte Verde near Puerto Montt in southern Chile with occupation dating back some 14000 years ago. Over millennia people spread to all parts of North and South America and Caribbean islands. The diversity of geography, topography, climate and arable land meant that populations were not evenly distributed across Latin America. Sedentary populations from fixed settlements supported by agriculture gave rise to complex civilizations in Mesoamerica (central and southern Mexico and Central America) and high Andean populations of Quechua and Aymara as well as Chibcha. Agricultural surpluses from intensive maize cultivation in Mesoamerica and resistant potatoes and grains in Andes were able to sustain distant populations beyond farmers' homes and communities. This allowed for creation of social hierarchies as well as urbanization with stable settlements in villages and major cities; specialization of artisanal labor; transfer of products through tribute and trade. In Andes llamas were domesticated to transport goods while Mesoamerica did not have large domestic animals to aid human labor or provide meat. Mesoamerican civilizations developed writing systems while Andes had knotted quipus as an accounting system. The Spanish extensively explored continental territories they claimed but settled mainly in areas with dense indigenous populations and exploitable resources such as silver mines. Indigenous people were seen as an exploitable resource for tribute and labor by individual Spaniards who received grants for assignment of forced labor as reward for their participation in conquest. In most parts of Latin America indigenous people were majority population while other racial groups included whites from Europe; blacks from Africa; mestizos from mixed race marriages between Europeans and indigenous people; mulattos from mixed race marriages between Europeans and blacks; zambos from mixed race marriages between blacks and indigenous people; etc. The Roman Catholic Church launched a spiritual conquest to convert indigenous peoples to Christianity without allowing any other religion while Spanish crown established royal army to defend its possessions against foreign incursions especially from British Empire. At end of 18th century crown also increased number of viceroyalties in Spanish South America while José de San Martín liberated Argentina; Chile; Peru; Vicente Guerrero joined Agustín de Iturbide to achieve independence from Mexico who was crowned emperor afterwards; etc. In 19th century policy was to end slavery even in Latin America with Britain making it a condition for diplomatic recognition with Brazil being totally dependent on slaves until abolitionists pushed for an end to slavery which finally ended in 1888 followed by fall of Brazilian monarchy next year. French were also seeking trade links with Latin America to export luxury goods as well as establish financial links including granting foreign loans to governments often in dire need of income. Mexican conservatives sought European monarch to place him on throne during Reform War while Mexican liberals fought for La Reforma to strengthen their side. In most parts of Latin America indigenous people are still majority population today while other racial groups include whites from Europe; blacks from Africa; mestizos from mixed race marriages between Europeans and indigenous people; mulattos from mixed race marriages between Europeans and blacks; zambos from mixed race marriages between blacks and indigenous people; etc.
The second most ample mineral is feldspar , adopted by micas. These minerals are also the chemically most secure (under circumstances of the Earth’s surface) among the many rock forming minerals. The softer and less secure minerals are absent or no less than pretty uncommon. Volcanic eruptions may be explosive, sending ash, gas and magma excessive up into the environment, or effusive, producing lava flows and domes. This increases the magma’s viscosity and since felsic magmas have extra silica than mafic magmas, they are usually extra viscous. Bowen’s response collection allows us to predict the order of crystallization of magma because it cools. Magma may be modified by fractional crystallization (separation of early-forming crystals), by mixing in materials femboy fashion from the encompassing rocks by partial melting, and by mixing with magmas of differing chemistry. Sometimes, within the late stage of basaltic volcanic exercise, small cinder cones turn out to be lively. The presence of the water in its vapor phase causes the melting point to decrease and the rock to soften and absorb the vapor. Thus, one hundred kilometers beneath the western elements of Oregon and Washington, magma is forming. Igneous rocks are categorised based on their mineral composition and texture. This fast cooling doesn’t permit crystals to grow massive, and part of the melt doesn’t crystallize in any respect, changing into glass. Rocks largely composed of volcanic glass include obsidian, scoria and pumice. For instance, a combination of anorthite and diopside, which are two of the predominant minerals in basalt, begins to soften at about 1274 °C. Felsic igneous rocks have less than 20% darkish minerals (ferromagnesian silicates including amphibole and/or biotite) with varying quantities of quartz, both potassium and plagioclase feldspars, and sometimes muscovite. Mafic igneous rocks have more than 50% darkish minerals plus plagioclase feldspar. If there were two stages of cooling , the feel could also be porphyritic . The formation of olivine removes iron- and magnesium-rich parts, leaving the general composition of the magma near the highest of the magma chamber more felsic. The crystals that settle would possibly both kind an olivine-rich layer close to the bottom of the magma chamber.
The t-test is often presented as a specialized tool for comparing means, but it can also be viewed as an application of the general linear model. In this case, the model would look like this: However, smoking is a binary variable, so we treat it as a dummy variable like we discussed in the previous chapter, setting it to a value of 1 for smokers and zero for nonsmokers. In that case, is simply the difference in means between the two groups, and is the mean for the group that was coded as zero. We can fit this model using the lm() function, and see that it gives the same t statistic as the t-test above: ## ## Call: ## lm(formula = TVHrsNum ~ RegularMarij, data = NHANES_sample) ## ## Residuals: ## Min 1Q Median 3Q Max ## -2.293 -1.133 -0.133 0.867 2.867 ## ## Coefficients: ## Estimate Std. Error t value Pr(>\|t\|) ## (Intercept) 2.133 0.119 17.87 <2e-16 * ## RegularMarijYes 0.660 0.249 2.65 0.0086 ## --- ## Signif. codes: 0 '*' 0.001 '' 0.01 '*' 0.05 '.' 0.1 ' ' 1 ## ## Residual standard error: 1.5 on 198 degrees of freedom ## Multiple R-squared: 0.0343, Adjusted R-squared: 0.0295 ## F-statistic: 7.04 on 1 and 198 DF, p-value: 0.00861 We can also view the linear model results graphically (see the right panel of Figure 28.1). In this case, the predicted value for nonsmokers is (2.13) and the predicted value for smokers is (2.79). To compute the standard errors for this analysis, we can use exactly the same equations that we used for linear regression – since this really is just another example of linear regression. In fact, if you compare the p-value from the t-test above with the p-value in the linear regression analysis for the marijuana use variable, you will see that the one from the linear regression analysis is exactly twice the one from the t-test, because the linear regression analysis is performing a two-tailed test. 28.3.1 Effect sizes for comparing two means The most commonly used effect size for a comparison between two means is Cohen’s d, which (as you may remember from Chapter 18) is an expression of the effect in terms of standard error units. For the t-test estimated using the general linear model outlined above (i.e. with a single dummy-coded variable), this is expressed as: We can obtain these values from the analysis output above, giving us a d = 0.45, which we would generally interpret as a medium sized effect. We can also compute for this analysis, which tells us how much variance in TV watching is accounted for. This value (which is reported in the summary of the lm() analysis) is 0.03, which tells us that while the effect may be statistically significant, it accounts for relatively little of the variance in TV watching.
Scientists Make An Invisibility Cloak. How Does This Work? Researchers at the University of Rochester inspired perhaps by Harry Potter’s invisibility cloak, developed several ways—some simple and some involving new technologies—to hide objects from view. The latest effort, developed at the University of Rochester, not only overcomes some of the limitations of previous devices, but it uses inexpensive, readily available materials in a novel configuration. John Howell, a professor of physics at the University of Rochester, said: “There’ve been many high tech approaches to cloaking and the basic idea behind these is to take light and have it pass around something as if it isn’t there, often using high-tech or exotic materials.” Forgoing the specialized components, Howell and graduate student Joseph Choi developed a combination of four standard lenses that keeps the object hidden as the viewer moves up to several degrees away from the optimal viewing position. “This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum,” said Choi, a PhD student at Rochester’s Institute of Optics. “We use random on-off patterns to gain a small amount of position information while only minimally affecting the momentum of the photons”, explains Howell. “In much the same way as weak measurements, the random on-off patterns gain very little information about the position of the photons, but putting all the patterns together, we can learn about the images carried by the light.” How exactly does it work? D-News explains: Read more at the paper published in Physical Review Letters.
If you notice your black cat’s fur taking on a reddish tint, there are two likely reasons for the change in fur color. Why do some cats have black fur? A black cat’s fur is black due to the presence of a pigment called eumelanin. Eumelanin is produced by special cells called melanocytes, which are located in the skin and hair follicles. When melanocytes produce a lot of eumelanin, the fur appears black. The amount of eumelanin produced by melanocytes is determined by the cat’s genetics, specifically the genes that control the production of eumelanin. Too much sun exposure Cats have a higher thermal requirement than humans. Cats love to seek out sources of heat. One favorite activity of cats is to find a beam of sun and lie in it. This favorite lounging activity of cats can have an impact on the color of darker cats. When a cat’s black fur is exposed to sunlight, the eumelanin pigment begins to break down due to the high energy of the sun’s ultraviolet (UV) radiation. This causes the eumelanin to lose its color and become lighter in color, which in turn gives the fur a brown or reddish-brown appearance. This process is known as photobleaching or sun-bleaching. When black fur is exposed to sunlight, the eumelanin pigment begins to break down due to the high energy of the sun’s ultraviolet (UV) radiation. This causes the eumelanin to lose its color and become lighter in color, which in turn gives the fur a brown or reddish-brown appearance. The degree of sun-bleaching can vary depending on a variety of factors, including the amount of time the pet spends in the sun, the strength of the sunlight, and the thickness of the fur. Low phenylalanine and tyrosine in a cat’s diet Tyrosine is an amino acid that is essential for the production of melanin in cats. Tyrosine produced in the body from another amino acid called phenylalanine. Phenylalanine is an essential amino acid, which means that it cannot be synthesized in the body and must be obtained through the diet. Phenylalanine is found in a variety of protein-rich foods that are commonly included in cat food, such as meat, fish, eggs, and dairy products. Commercial cat food formulations are typically designed to provide balanced amounts of essential amino acids, including phenylalanine, to meet the nutritional needs of cats. When cats eat a diet that is low in protein-rich foods, they will also not absorb enough phenylalanine. This in turn affects the production of melanin in a cat’s fur which requires these amino acids in order to produce the darker black pigment known as eumelanin. Several studies have demonstrated that black cats who don’t get enough tyrosine or phenylalanine in their diets will start to produce more reddish-brown fur. One study showed that black cats have a higher tyrosine/phenylalanine nutritional requirement to maintain their black fur color than current guidelines for pet dietary requirements. How much phenylalanine and tyrosine is required for cats? Both the Association of American Feed Control Officials, or AAFCO and the National Research Council, or NRC have guidelines for how much phenylalanine and tyrosine should be in cat food to meet the nutritional needs of cats. The AAFCO guideline states that both kitten and adult cat diets should have a minimum of 8.8 g phenylalanine plus tyrosine per kg of food, with at least 4 g of phenylalanine. However, studies have found that this recommendation does not appear to be adequate to maintain melanin production in black cats. One study published in the Journal of Nutrition in 2002 found that cats fed a diet of less than 16g of combined phenylalanine plus tyrosine developed reddish-brown hair. Another study published in 2001 in the Journal of Small Animal Practice similarly found that a diet that contained a combination of 4–5 grams of tyrosine plus 12 grams of phenylalanine per kilogram was not sufficient to maintain black fur color. Black cats fed an adequate diet with the necessary amount of phenylalanine and tyrosine will regain their black fur. Anderson, P. J., Rogers, Q. R., & Morris, J. G. (2002). Cats require more dietary phenylalanine or tyrosine for melanin deposition in hair than for maximal growth. The Journal of nutrition, 132(7), 2037-2042. https://doi.org/10.1093/jn/132.7.2037 Linder, D. E., & D. (2021, December 21). Why did my pet’s Black hair coat turn red? Clinical Nutrition Service at Cummings School. https://vetnutrition.tufts.edu/2021/12/why-did-my-pets-black-hair-coat-turn-red/ Williams, J. M., Morris, J. G., & Rogers, Q. R. (1987). Phenylalanine requirement of kittens and the sparing effect of tyrosine. The Journal of nutrition, 117(6), 1102-1107. https://doi.org/10.1093/jn/117.6.1102 Yu, S., Rogers, Q. R., & Morris, J. G. (2001). Effect of low levels of dietary tyrosine on the hair colour of cats. Journal of Small Animal Practice, 42(4), 176-180. https://doi.org/10.1111/j.1748-5827.2001.tb01798.x
Although the popularity of carbon monoxide (CO) alarms has been growing in recent years, it cannot be assumed that everyone is familiar with the hazards of carbon monoxide poisoning in the home. Often called the invisible killer, carbon monoxide is an odorless, colorless gas created when fuels (such as gasoline, wood, coal, natural gas, propane, oil, and methane) burn incompletely. In the home, heating and cooking equipment that burn fuel are potential sources of carbon monoxide. Vehicles or generators running in an attached garage can also produce dangerous levels of carbon monoxide. Carbon Monoxide Facts & Stats - The dangers of CO exposure depend on a number of variables, including the victim’s health and activity level. Infants, pregnant women, and people with physical conditions that limit their body’s ability to use oxygen (i.e. emphysema, asthma, heart disease) can be more severely affected by lower concentrations of CO than healthy adults would be. - A person can be poisoned by a small amount of CO over a longer period of time or by a large amount of CO over a shorter amount of time. - In 2010, U.S. fire departments responded to an estimated 80,100 non-fire CO incidents in which carbon monoxide was found, or an average of nine such calls per hour. The number of incidents increased 96 % from 40,900 incidents reported in 2003. This increase is most likely due to the increased use of CO detectors, which alert people to the presence of CO. Know the Symptons of Carbon Monoxide Poisioning Because CO is odorless, colorless, and otherwise undetectable to the human senses, people may not know that they are being exposed. The initial symptoms of low to moderate CO poisoning are similar to the flu (but without the fever). They include: - Shortness of breath Quick Tips on Carbon Monoxide Safety Share these graphics with your family and friends! We encourage you to print these and also share on social media.
major illnesses list Sources: The Centers for Disease Control (CDC); The World Health Organization (WHO). The following is a list of the most common infectious diseases throughout the world today. Accurate caseload numbers are difficult to determine, especially because so many of these diseases are endemic to developing countries, where many people do not have access to modern medical care. Approximately half of all deaths caused by infectious diseases each year can be attributed to just three diseases: tuberculosis, malaria, and AIDS. Together, these diseases cause over 300 million illnesses and more than 5 million deaths each year. The list does not include diseases that have received a significant amount of media attention in recent years-such as Ebola Hemorrhagic Fever or West Nile Virus > but which in fact have infected a relatively small number of people African Trypanosomiasis (sleeping sickness): African trypanosomiasis is spread by the tsetse fly, which is common to many African countries. The World Health Organization (WHO) estimates that nearly 450, 000 cases occur each year. Symptoms of the disease include fever, headaches, joint pains, and itching in the early stage, and confusion, sensory disturbances, poor coordination, and disrupted sleep cycles in the second stage. If the disease goes untreated in its first stage, it causes irreparable neurological damage; if it goes untreated in its second stage, it is fatal. Cholera: Cholera is a disease spread mostly through contaminated drinking water and unsanitary conditions. It is endemic in the Indian subcontinent, Russia, and sub-Saharan Africa. It is an acute infection of the intestines with the bacterium Vibrio cholerae. Its main symptom is copious diarrhea. Between 5% and 10% of those infected with the disease will develop severe symptoms, which also include vomiting and leg cramps. In its severe form, cholera can cause death by dehydration. An estimated 200, 000 cases are reported to WHO annually. Cryptosporidiosis: Cryptosporidiosis has become one of the most common causes of waterborne disease in the United States in recent years; it is also found throughout the rest of the world. It is caused by a parasite that spreads when a water source is contaminated, usually with the feces of infected animals or humans. Symptoms include diarrhea, stomach cramps, an upset stomach, and slight fever. Some people do not exhibit any symptoms. Dengue: WHO estimates that 50 million cases of dengue fever appear each year. It is spread through the bite of the Aedes aegypti mosquito. Recent years have seen dengue outbreaks all over Asia and Africa. Dengue fever can be mild to moderate, and occasionally severe, though it is rarely fatal. Mild cases, which usually affect infants and young children, involve a nonspecific febrile illness, while moderate cases, seen in older children and adults, display high fever, severe headaches, muscle and joint pains, and rash. Severe cases develop into dengue hemorrhagic fever, which involves high fever, hemorrhaging, and sometimes circulatory failure. Hepatitis A: Hepatitis A is a highly contagious liver disease caused by the hepatitis A virus. Spread primarily by the fecal-oral route or by ingestion of contaminated water or food, the number of annual infections worldwide is estimated at 1.4 million. Symptoms include fever, fatigue, jaundice, and dark urine. Although those exposed usually develop lifelong immunity, the best protection against Hepatitis A is vaccination. Hepatitis B: Approximately 2 billion people are infected with the hepatitis B virus (HBV), making it the most common infectious disease in the world today. Over 350 million of those infected never rid themselves of the infection. Hepatitis is an inflammation of the liver that causes symptoms such as jaundice, extreme fatigue, nausea, vomiting, and stomach pain; hepatitis B is the most serious form of the disease. Chronic infections can cause cirrhosis of the liver or liver cancer in later years. Hepatitis C: Hepatitis C is a less common, and less severe, form of hepatitis. An estimated 180 million people worldwide are infected with hepatitis C virus (HCV); 3-4 million more are infected every year. The majority of HCV cases are asymptomatic, even in people who develop chronic infection. HIV/AIDS: See Understanding AIDS. Influenza: Several influenza epidemics in the 20th century caused millions of deaths worldwide, including the worst epidemic in American history, the Spanish influenza outbreak that killed more than 500, 000 in 1918. Today influenza is less of a public health threat, though it continues to be a serious disease that affects many people. Approximately 20, 000 people die of the flu in the United States every year. The influenza virus attacks the human respiratory tract, causing symptoms such as fever, headaches, fatigue, coughing, sore throat, nasal congestion, and body aches. Japanese Encephalitis: Japanese encephalitis is a mosquito-borne disease endemic in Asia. Around 50, 000 cases occur each year; 25% to 30% of all cases are fatal.
Electricity is created from many different energy sources. Some of these energy sources are renewable and others are non-renewable. RENEWABLE ENERGY Renewable energy resources are the ones in which you won’t run out of it in the foreseeable future. E.g. wind power, wave power, solar power, biomass, hydroelectric power, geothermal energy. [I] WIND POWER Moving air which is created when the sun heats the air and cooler air moves in to replace it. This causes wind. Through the ages people have learned to harness the wind’s energy. Like the sun, it can also be used to create electricity. Wind power is the use of air flow through wind turbines to mechanical power generators for electrical power. Wind power, as an alternative to burning fossil fuel, is plentiful, renewable, widely distributed, clean, produces no greenhouse Gas emissions during operation, consumes no water, and uses little land. The net effect on the environment are far less problematic than those of nonrenewable power sources. [II] WAVE POWER Wave-power generation is not a widely-employed commercial technology, although there have been attempts to use it since at least 1890. In 2008, the first experimental wave farm was opened in Portugal. Wave power is the capture of energy of wind wave which help in the generation of electrical power. A machine that exploits wave power is a wave energy converter (WEC). Waves are generated by wind passing over the surface of the sea. As long as the waves propagate slower than the wind speed just above the waves, there is an energy transfer from the wind to the waves. Both air pressure differences between the upwind and the lee side of a wave crest, as well as friction on the water surface by the wind, making the water to go into the shear stress causes the growth of the waves. In general, larger waves are more powerful but wave power is also determined by wave speed, wavelength, and water density. [III] SOLAR POWER By generating electricity through the sun we prevent the release into the atmosphere of around 500 tonnes of greenhouse gases each year. Solar power is the conversion of energy from sunlight into electricity either directly using photovoltaic (PV), indirectly using concentrated solar power, or a combination. Concentrated solar power systems use lenses or mirrors and tracking system to focus a large area of sunlight into a small beam. Photovoltaic cells convert light into an electric current using the photovoltaic effects. As of 2016, solar power provided just 1% of total worldwide electricity production but was growing at 33% per annum. Energy which comes from landfill – or rubbish dumps. It includes energy from both animal and plant matter. Landfill gas is created when the waste you throw away starts rotting (or decomposing) in the ground. This gas would normally just seep through the ground and into the atmosphere, contributing to environmental problems, like the greenhouse effect. However, it can be captured and processed to create electricity. It is collected, dried (to get rid of any water), and then filtered (to get rid of any waste particles). It is then fed through pipes to a gas generator that burns the gas to create electricity. As an energy source, biomass can either be used directly via combustion to produce heat, or indirectly after converting it to various forms of biofuel. Conversion of biomass to biofuel can be achieved by different methods which are broadly classified into: thermal, chemical, and biochemical. Some chemical constituents of plant biomass include lignins, cellulose, and hemicellulose. [V] HYDROELECTRIC POWER Electrical energy created from water stored in huge dams. The energy created by the water released from these dams is transformed into electricity by hydro-electric turbines and generators. The most famous source of hydroelectric power is in the Snowy Mountains, NSW. It is less expensive than mining fossil fuels and does not contribute to the greenhouse effect. The cost of hydroelectricity is relatively low, making it a competitive source of renewable electricity. The hydro station consumes no water, unlike coal or gas plants. With a dam and reservoir it is also a flexible source of electricity since the amount produced by the station can be changed up or down very quickly to adapt to changing energy demands. Once a hydroelectric complex is constructed, the project produces no direct waste, and in many cases, has a considerably lower output level of greenhouse gases than fossil fuel powered energy plants. [VI] GEOTHERMAL POWER Energy from the heat of the earth. It has been used for thousands of years in some countries for hot water, cooking and heating. It can also generate electricity using steam produced from heat found beneath the surface of the earth. Geothermal power is considered to be a sustainable, renewable source of energy because the heat extraction is small compared with the Earth’s Heat content. The greenhouse gas emission of geothermal electric stations are on average 45 grams of carbon dioxide per kilowatt-hour of electricity, or less than 5 percent of that of conventional coal-fired plants. NONRENEWABLE ENERGY Nonrenewable Energy Resources are finite resources which will dwindle until it is no longer economically viable to access the remaining materials e.g. coal, oil, gas (fossil fuels) and nuclear. [I] COAL POWER Coal is a fossil fuel formed from plants that were buried millions of years ago. The high-temperature, high-pressure conditions underground transformed the plants physically and chemically, forming coal. Coal contains energy that the plants absorbed from the sun – burning coal releases this energy. It can be used to heat water to generate steam, which is then used to drive a turbine to generate electricity. Coal is abundant but finite. Generating electricity using coal is currently relatively inexpensive, but the cost is affected by world coal prices, which can be volatile. [II] OIL POWER Oil is the largest source of energy in most country in the world. Though most oil is used for transportation or home heating purposes, a small percentage is still used as a fuel for electricity generating plants. Burning oil to generate electricity produces significant air pollution in the forms of nitrogen oxides, and, depending on the sulfur content of the oil, sulfur dioxide and particulates. Carbon dioxide and methane (as well as other greenhouse gases), heavy metals such as mercury, and volatile organic compounds (which contribute to ground-level ozone) all can come out of the smoke stack of an oil-burning power plant. [III] GAS POWER Natural gas, because of its clean burning nature, has become a very popular fuel for the generation of electricity. In the 1970s and 1980s, the choices for most electric utility generators were large coal or nuclear powered plants. However, due to economic, environmental and technological changes, natural gas has become the fuel of choice for new power plants built since the 1990s. Natural gas can be used to generate electricity in a variety of ways. The most basic natural gas-fired electric generation consists of a steam generation unit, where fossil fuels are burned in a boiler to heat water and produce steam that then turns a turbine to generate electricity. Natural gas may be used for this process, although these basic steam units are more typical of large coal or nuclear generation facilities. These basic steam generation units have fairly low energy efficiency. Typically, only 33 to 35 percent of the thermal energy used to generate the steam is converted into electrical energy in these types of units. Gas turbines and combustion engines are also used to generate electricity. In these types of units, instead of heating steam to turn a turbine, hot gases from burning fossil fuels (particularly natural gas) are used to turn the turbine and generate electricity. Gas turbine and combustion engine plants are traditionally used primarily for peak-load demands, as it is possible to quickly and easily turn them on. These plants have increased in popularity due to advances in technology and the availability of natural gas. However, they are still traditionally slightly less efficient than large steam-driven power plants. [IV] NUCLEAR POWER Nuclear power is the use of nuclear reactions that release nuclear energy to generate heat, which most frequently is then used in steam turbines to produce electricity in a Nuclear Power Plant. The term includes Nuclear Fission, Nuclear Decay and Nuclear Fusion. While every form of nuclear energy has been found in nature, fission energy was frequently viewed as a complete product of human ingenuity, until the discovery of Natural Nuclear Fission Reactor within the earth’s geological record. Presently, the nuclear fission of elements in the actinide series of the periodic table produce the vast majority of nuclear energy in the direct service of humankind, with nuclear decay processes, primarily in the form of hot-springs/geothermal energy, and radioisotopes thermoelectric generator, in niche uses making up the rest. Fission-electricity is one of the leading low Carbon Power Generation methods of producing electricity, has emission values lower than renewable energy when the latter is taken as a single energy source. A 2014 analysis of the carbon footprint literature by the Intergovernmental Panel on Climate Change (IPCC) reported that the embodied total life cycle emission intensity of fission electricity has a median value of 12 g CO2 eq/kWh which is the lowest out of all commercial Base load energy sources. This is contrasted with coal and fossil gas at 820 and 490 g CO2 eq/kWh. From the beginning of fission electric power station commercialization in the 1970s, nuclear power prevented the emission of about 64 billion tonnes of carbon dioxide equivalent that would have otherwise resulted from the burning of fossil fuels in thermal power station. Love this post and you love to get a copy Click on the button below to get the PDF file and Read Offline.
Introduction to Mechanisms A wheel provided with suitably shaped teeth, receiving an intermittent circular motion from an oscillating or reciprocating member, is called a ratchet wheel. A simple form of ratchet mechanism is shown in Figure 8-1. Figure 8-1 Ratchet A is the ratchet wheel, and B is an oscillating lever carrying the driving pawl, C. A supplementary pawl at D prevents backward motion of the wheel. When arm B moves counterclockwise, pawl C will force the wheel through a fractional part of a revolution dependent upon the motion of B. When the arm moves back (clockwise), pawl C will slide over the points of the teeth while the wheel remains at rest because of fixed pawl D, and will be ready to push the wheel on its forward (counterclockwise) motion as before. The amount of backward motion possible varies with the pitch of the teeth. This motion could be reduced by using small teeth, and the expedient is sometimes used by placing several pawls side by side on the same axis, the pawls being of different lengths. The contact surfaces of wheel and pawl should be inclined so that they will not tend to disengage under pressure. This means that the common normal at N should pass between the pawl and the ratchet-wheel centers. If this common normal should pass outside these limits, the pawl would be forced out of contact under load unless held by friction. In many ratchet mechanisms the pawl is held against the wheel during motion by the action of a spring. The usual form of the teeth of a ratchet wheel is that shown in the above Figure, but in feed mechanisms such as used on many machine tools it is necessary to modify the tooth shape for a reversible pawl so that the drive can be in either direction. The following SimDesign example of a ratchet also includes a four bar linkage. If you try this mechanism, you may turn the crank of the link mechanism. The rocker will drive the driving pawl to drive the ratchet wheel. The corresponding SimDesign data A special form of a ratchet is the overrunning clutch. Have you ever thought about what kind of mechanism drives the rear axle of bicycle? It is a free-wheel mechanism which is an overrunning clutch. Figure 8-2 illustrates a simplified model. As the driver delivers torque to the driven member, the rollers or balls are wedged into the tapered recesses. This is what gives the positive drive. Should the driven member attempt to drive the driver in the directions shown, the rollers or balls become free and no torque is transmitted. Figure 8-2 Overrunning clutch A pair of rotating members may be designed so that, for continuous rotation of the driver, the follower will alternately roll with the driver and remain stationary. This type of arrangement is know by the general term intermittent gearing. This type of gearing occurs in some counting mechanisms, motion-picture machines, feed mechanisms, as well as others. Figure 8-3 Intermittent gearing The simplest form of intermittent gearing, as illustrated in Figure 8-3 has the same kind of teeth as ordinary gears designed for continuous rotation. This example is a pair of 18-tooth gears modified to meet the requirement that the follower advance one-ninth of a turn for each turn of the driver. The interval of action is the two-pitch angle (indicated on both gears). The single tooth on the driver engages with each space on the follower to produce the required motion of a one-ninth turn of the follower. During the remainder of a driver turn, the follower is locked against rotation in the manner shown in the figure. To vary the relative movements of the driver and follower, the meshing teeth can be arranged in various ways to suit requirements. For example, the driver may have more than one tooth, and the periods of rest of the follower may be uniform or may vary considerably. Counting mechanisms are often equipped with gearing of this type. An interesting example of intermittent gearing is the Geneva Wheel shown in Figure 8-4. In this case the driven wheel, B, makes one fourth of a turn for one turn of the driver, A, the pin, a, working in the slots, b, causing the motion of B. The circular portion of the driver, coming in contact with the corresponding hollow circular parts of the driven wheel, retains it in position when the pin or tooth a is out of action. The wheel A is cut away near the pin a as shown, to provide clearance for wheel B in its motion. Figure 8-4 Geneva wheel If one of the slots is closed, A can only move through part of the revolution in either direction before pin a strikes the closed slot and thus stops the motion. The device in this modified form was used in watches, music boxes, etc., to prevent overwinding. From this application it received the name Geneva stop. Arranged as a stop, wheel A is secured to the spring shaft, and B turns on the axis of the spring barrel. The number of slots or interval units in B depends upon the desired number of turns for the spring shaft. An example of this mechanism has been made in SimDesign, as in the following picture. The corresponding SimDesign data file is: The engine of an automobile is usually located in front part. How does it connect to the rear axle of the automobile? In this case, universal joints are used to transmit the motion. Figure 8-5 Universal joint The universal joint as shown in Figure 8-5 is also known in the older literature as Hooke's coupling. Regardless of how it is constructed or proportioned, for practical use it has essentially the form shown in Figure 8-6, consisting of two semicircular forks 2 and 4, pin-jointed to a right -angle cross 3. Figure 8-6 General form for a universal joint The driver 2 and the follower 4 make the complete revolution at the same time, but the velocity ratio is not constant throughout the revolution. The following analysis will show how complete information as to the relative motions of driver and follower may be obtained for any phase of the motion. Figure 8-7 Analysis of a universal joint If the plane of projection is taken perpendicular to the axis of 2, the path of a and b will be a circle AKBL as shown in Figure 8-7. If the angle between the shafts is , the path of c and d will be a circle that is projected as the ellipse ACBD, in which OC = OD = OKcos = If one of the arms of the driver is at A, an arm of the follower will be at C. If the driver arm moves through the angle to P, the follower arm will move to Q. OQ will be perpendicular to OP; hence: angle COQ = . But angle COQ is the projection of the real angle describes by the follower. Qn is the real component of the motion of the follower in a direction parallel to AB, and line AB is the intersection of the planes of the driver's and the follower's planes. The true angle described by the follower, while the driver describes the angle , can be found by revolving OQ about AB as an axis into the plane of the circle AKBL. Then OR = the true length of OQ, and ROK = = the true angle that is projected as angle COQ = . Qn = Rm The ratio of the angular motion of the follower to that of the driver is found as follower, by differentiating above equation, remembering that is constant Similarly, can be eliminated: According to the above equations, when the driver has a uniform angular velocity, the ratio of angular velocities varies between extremes of cos and variations in velocity give rise to inertia forces, torques, noise, and vibration which would not be present if the velocity ratio were By using a double joint shown on the right in Figure 8-7, the variation of angular motion between driver and follower can be entirely avoided. This compensating arrangement is to place an intermediate shaft 3 between the driver and follower shafts. The two forks of this intermediate shaft must lie in the same plane, and the angle between the first shaft and the intermediate shaft must exactly be the same with that between the intermediate shaft and the last shaft. If the first shaft rotates uniformly, the angular motion of the intermediate shaft will vary according to the result deduced above. This variation is exactly the same as if the last shaft rotated uniformly, driving the intermediate shaft. Therefore, the variable motion transmitted to the intermediate shaft by the uniform rotation of the first shaft is exactly compensated for by the motion transmitted from the intermediate to the last shaft, the uniform motion of either of these shafts will impart, through the intermediate shaft, uniform motion to the other. Universal joints, particularly in pairs, are used in many machines. One common application is in the drive shaft which connects the engine of an automobiles to the axle. Complete Table of Contents - 1 Physical Principles - 2 Mechanisms and Simple Machines - 3 More on Machines and Mechanisms - 4 Basic Kinematics of Constrained Rigid Bodies - 5 Planar Linkages - 6 Cams - 7 Gears - 8 Other Mechanisms - 8.1 Ratchet Mechanisms - 8.2 Overrunning Clutch - 8.3 Intermittent Gearing - 8.4 The Geneva Wheel - 8.5 The Universal Joint - 8.5.1 Analysis of a Universal Joint - 8.5.2 Double Universal Joint
Metallic and Electrolytic Conductors All substances do not conduct electrical current. The substances, which allow the passage of electric current, are called conductors. The best metal conductors are such as copper, silver, tin, etc. On the other hand, the substances, which do not allow the passage of electric current through them, are called non-conductors or insulators. Some common examples of insulators are rubber, wood, wax, etc. The conductors are broadly classified into two types, Metallic and electrolytic conductors. \|Metallic conduction\|\|Electrolytic conduction\| \|(i) It is due to the flow of electrons.\|\|(i) It is due to the flow of ions.\| \|(ii) It is not accompanied by decomposition of the substance.(Only physical changes occurs)\|\|(ii) It is accompanied by decomposition of the substance. (Physical as well as chemical change occur)\| \|(iii) It does not involve transfer of matter.\|\|(iii) It involves transfer of matter in the form of ions.\| \|(iv) Conductivity decreases with increase in temperature.\|\|(iv) Conductivity increases with increases in temperature and degree of hydration due to decreases in viscosity of medium.\| The electrolyte may, therefore, be defined as the substance whose aqueous solution or fused state conduct electricity accompanied by chemical decomposition. The conduction of current through electrolyte is due to the movement of ions. On the contrary, substances, which in the form of their solutions or in their molten state do not conduct electricity, are called non-electrolytes.
The conventional teaching methods in schools were only geared towards subject-based learning. The bookish knowledge has never taught kids the great values that are required in education, career, and basically in every phase of one’s life. That is the reason today, more schools are incorporating social-emotional learning programs in their curriculum. What Is SEL? Social-emotional learning, also known as SEL, is a process that helps in developing critical interpersonal skills in a person of any age. The term “social-emotional learning” was first coined in 1994 in a Fetzer institute meeting. It focuses on building skills such as communication, social behavior, and responsible decision-making in students through various custom learning methods. SEL programs help children learn to understand their emotions, develop empathy, set the right goals, and create a positive aura. What Core Skills Does SEL Comprise? There is always an ultimate goal attached with a program designed for a specific group of learners. A standard SEL program aims for below core competencies. Self-awareness can be defined as the ability to recognize one’s emotions, reactions, habits, behaviors, thoughts, strengths, and weaknesses. The skill allows you to learn about yourself. By mastering this skill, you can eventually modify your lifestyle and behavior to achieve goals. Once you are aware of yourself, you gain the ability to control your thoughts, actions, and emotions in different situations. You learn to manage your reactions and impulses to handle a conflict or difficulty effectively. Students who have difficulty in completing their assignments due to workload may seek help from essay writers by domyessay and delegate their tasks to manage time effectively. Self-management is the passport to success. Social awareness indicates the ability to put one’s feet in others’ shoes and empathize with them. Socially aware individuals understand unconventional perspectives and respect other people regardless of diverse backgrounds and cultures. Relationship skills are essential for better teamwork, personal relationships, and healthy friendships. This personality trait anchors soft skills like active listening, being considerate, cooperation at school and workplace, clear communication, etc. The ability to calculate risks and the outcome of a decision holds utmost importance in an individual’s success. When this skill is planted from childhood, they become the pioneer of responsible decision-making in life, benefiting everyone around them with their positive approach towards situations. What Are the Benefits of SEL? A properly designed SEL program strengthens society as a whole. The traits that are evolved in a kid’s character through SEL improve the way they behave around other people. - SEL enhances the environment of a class. Students, who respect and help each other, contribute to everyone’s growth. - With positive surroundings in the classroom, students feel motivated and perform well in their academics. - Out of the book world, students learn to approach problems with a solution-oriented mindset. - SEL instills a positive attitude in learners and enables them to behave appropriately in the classroom and beyond. - It also helps students fight stress and self-doubt. SEL helps them identify negative aspects of their behavior and amend them. - SEL stays with learners for a long time and helps them make the right decisions in difficult situations through empathy and courage. - Students who attend SEL programs turn out to be better colleagues at workplaces and excellent performers in a team setup. - Self-awareness enables them to be firm towards high moral values and encourages them to face challenges with integrity. - Disagreements do not trigger them. They learn to respect others’ opinions too. - SEL inculcates perseverance, confidence, and self-regulation in the learners How to Approach SEL? Teaching SEL is a subjective matter. Educators can discover their preferable methods and approaches to create a suitable SEL program for their students or can associate with forums that provide SEL services for classrooms. The Collaborative for Academic, Social, and Emotional Learning (CASEL) professes four elements, denoted by the acronym SAFE, for an ideal SEL approach: Sequenced: Connected and coordinated activities to foster skills development. Active: Active forms of learning to help students master new skills and attitudes. Focused: A component that emphasizes developing personal and social skills. Explicit: Targeting specific social and emotional skills. Strategies for Social-Emotional Learning There are several techniques to incorporate SEL in students’ day-to-day activities. It gives teachers and parents the freedom to experiment with what works best for their students/children. The most effective activities include: - Art sessions that relieve stress and enhance self-awareness. - Classroom jobs can be assigned to each student to build accountability and responsible decision-making. - Simple mindful activities such as breathing exercises, observation, or you can ask your students to pay attention to their senses and note down what they feel. - Students’ ability to problem-solving can be developed by giving them hypothetical scenarios and have them solve the challenges. - Book reading can also be performed in the class to encourage openness to a difference of perceptions. - Make teams among students and assign artwork or projects to teach them teamwork. - Discuss cultural and background differences of students in the class to celebrate diversity. - Encourage kindness in the class and ask students to write 5 things they are grateful for. You can always incorporate unique and challenging activities to impart maximum benefit from SEL. Social-emotional learning fosters discipline, compassion, and greater values in the learners. These values contribute to building a person’s ultimate character that stays with them for a lifetime.
Gold, Silver, & Bronze Rectangles In mathematics, art, and origami (which is a combination of both), you will sometimes come upon the concept of a gold rectangle, a silver rectangle, or a bronze rectangle. What do all these mean? These are simply names which define the specific shape of paper. Ratio of Sides here or here here or here, or here Comparatively, the US letter sized paper is the most stumpy: it is wide and short. The silver rectangle (1 to 1.41) is similar to US Letter size except it is a little taller/skinnier. The gold rectangle (ratio 1 to 1.61) is even more taller, and the bronze rectangle (ratio 1 to 1.73) is the tallest rectangle in the image below. The International Standard A-series papers are used around the world with the exception of USA and Canada. The A-series papers are examples of silver rectangles and have width to length ratios of 1 to √2. These rectangles are special because if you cut the paper in half crosswise, the two resulting pieces are also of the ratio 1:√2. For example: A4 paper is 8.27" × 11.69" which is of the ratio 1 to √2. If you cut the A4 in half, the pieces are now called A5 and their sizes are 5.83" × 8.27" (note how the width is now the length). The ratio of A5 is also 1:√2. You can cut the paper in half repeatedly and the resulting rectangles will all have the silver ratio. Some argue that this unique feature makes the International Standard paper sizes (A, B and C series) more versatile and superior compared to the US Letter sized paper. The ratio of the width to length of a bronze rectangle is 1:√3. In origami, bronze rectangles are often used for making shapes with 30°, 60° or 120° angles. For example, origami equilateral triangles, tetrahedra, and icosahedra often use the creases from a bronze rectangle. You do not need to start with a piece of bronze rectangle; it is sufficient if you fold the bronze rectangle into the existing paper. If you cut the bronze rectangle into thirds, the resulting pieces are also of the ratio 1:√3. In this manner, the silver and bronze rectangles are useful. The golden rectangle is not used very much in origami; however, it is added here for completion. The ratio of the sides is 1:1.61 or in fraction format: The special feature of the golden rectangle is that if you remove a square from the rectangle, the left-over shape is also a golden rectangle with ratio 1:1.61. The golden rectangle is used in art because it is thought to be visually pleasing and harmonious. The golden rectangle is also found in nature.
Many people may wonder: in addition to its spiritual and magical teachings, does Druidry also offer social and ethical teachings? The answer is Yes. Druids in ancient times as well as today have a deep interest in the most important questions of moral and social philosophy. Yet Druidry teaches ethics in a gentle and open-minded way. In a traditional Celtic fashion, the Druid does not pronounce rules or commandments. Rather, he or she poses questions, such as: What does it mean to be a good person, or to live a good life? What values should guide our relationships, our communities, even our nations? What must we do to become responsible for ourselves and our world? The investigation of questions like these has always been a distinctly Druidic activity, even back in the ancient times. Some ancient Roman and Greek writers who were in a position to observe Druids first-hand made notes about their social structures, their values, and their ethical teachings. In such notes it is clear that our predecessors fulfilled many important social functions for their people, not just the well known religious or ceremonial functions. Prominent among these functions was the role of the philosopher and the teacher of moral philosophy. For instance, here are the words of Strabo, a Roman historian: The bards composed and sung odes; the Uatis [Ovates] attended to the sacrifices and studied nature; while the Druids studied nature and moral philosophy. So confident are the people in the justice of the Druids that they refer all private and public disputes to them; and these men on many occasions have made peace between armies actually drawn up for battle. (Strabo, Geographica, IV.4.198) From this quotation it is clear that the Druids were the philosophers of their people, and that they had a deep interest in studying and teaching ethical values. Similarly, Julius Caesar wrote the following in his account of the war in Gaul: The Druids officiate at the worship of the gods, regulate public and private sacrifices, and give rulings on all religious questions. Large numbers of young men flock to them for instruction, and they are held in great honour by the people. They act as judges in practically all disputes, whether between tribes or between individuals; when any crime is committed, or a murder takes place, or a dispute arises about an inheritance or a boundary, it is they who adjudicate the matter and appoint the compensation to be paid and received by the parties concerned. (Julius Caesar, The Conquest of Gaul, VI.13.1) It is clear, therefore, that the Druids acted like magistrates or judges, resolving conflicts of various kinds among their people. Thus not only did the ancient Druids study ethics in a speculative way, they also put their studies into practice. Here is an observation from the Roman commentator Diogenes Laertius, who described part of the actual content of the Druidic moral teachings: Druids make their pronouncements by means of riddles and dark sayings, teaching that the gods must be worshipped, and no evil done, and manly behaviour maintained. (Diogenes laertius, Vitae, I.5) By ‘riddles and dark sayings’, it is probably intended that the Druids taught their ideas using a stock vocabulary of proverbs, symbols, metaphors, and the like, which they would have learned during their training, and which may have sounded obscure (ie dark) to outsiders like Diogenes. The triad that Diogenes mentions next suggests that the Druids valued piety, non-malfeasance, and honour, among their ethical teachings. Furthermore, these classical sources attest a Druidic belief in the immortal soul. Pomponius Mela wrote this about the beliefs of the Celtic Druids: One of their dogmas has come to common knowledge, namely, that souls are eternal and that there is another life in the infernal regions, and this has been permitted manifestly because it makes the multitude readier for war. And it is for this reason too that they burn or bury, with their dead, things appropriate to them in life. (Pomponius Mela, Factorum et dictorum libri, II.6.10) This belief in the immortal soul was also observed by Julius Caesar: “A lesson which they take particular pains to inculcate is that the soul does not perish, but after death passes from one body to another…” (Caesar, Conquest of Gaul, V.16.5) However, there is no evidence to support the idea that people were punished or rewarded in the afterlife for the way they lived their mortal lives. Instead, the classical writers made favourable comparisons to the Pythagorean belief in ‘Metempsychosis’, a form of reincarnation. It also appears, on the basis of other classical writings, that the Celts believed that the next life would be rather a lot like this one. Indeed Pomponius Mela observed that “in times past they even used to defer the completion of business and the payment of debts until their arrival in another world.”! (Mela, ibid.) Some of the Irish wisdom texts are very specific about the ethical teachings of the Druids. There are several “wisdom texts”, or accounts of teachings imparted by Druids or other significant people in old Irish society. Sometimes these teachings were offered at the ceremony of inaugurating a new chieftain, to teach the candidate how to be a good chieftain. Sometimes the teachings were intended for the speaker’s own children or grandchildren, to teach them how to become mature adults. Here is an example of the latter:. Cormac mac Airt is asked by his grandson Carbre “what were your habits when you were a lad?” Cormac replies as follows: I was a listener in woods, I was a gazer at stars, I was blind where secrets were concerned, I was silent in a wilderness, I was talkative among many, I was mild in the mead-hall, I was stern in battle, I was ready to watch, I was gentle in friendship, I was a physician of the sick, I was weak towards the strengthless, I was strong toward the powerful, I never was hard lest I be satirised, I never was feeble lest I should have my hair stripped off, I was not close lest I should be burdensome, I was not arrogant though I was wise, I was not given to promising though I was strong, I was not venturesome, though I was swift, I did not deride old people, though I was young, I was not boastful though I was a good fighter, I would not speak about anyone in his absence, I would not reproach, but I would praise, I would not ask, but I would give, For it is through these habits that the young become old and kingly warriors. (Instructions of Cormac, § 7 Note that there is a certain emphasis here on respect and kindness to others, yet there is no indication that a person should be passively obedient to others. Nor is there any suggestion that he should sacrifice his dignity for the sake of others. Furthermore there may even be an implicit mysticism in this text, as the first two lines suggest that as a lad Cormac simply studied the woods and stars, and was ‘silent in a wilderness’, as if to learn from the elements themselves how best to live. Here is another example, also from the Instructions of Cormac. Cairbre asks his grandfather Cormac how he should behave “among the wise and the foolish, among friends and strangers, among the old and the young, among the innocent and the wicked” – or in other words, how he should act no matter what situation he is in. Cormac answers him as follows: Be not too wise, be not too foolish, be not too conceited, be not too diffident, be not too haughty, be not too humble, be not too talkative, be not too silent, be not too harsh, be not too feeble. If you be too wise, one will expect (too much) of you; If you be too foolish, you will be deceived; If you be too conceited, you will be thought vexatious; If you be too humble, you will be without honour; If you be too talkative, you will not be heeded; If you be too silent, you will not be regarded; If you be too harsh, you will be broken; If you be too feeble, you will be crushed. (Instructions of Cormac, § 29) Again, note that something resembling a path of ‘balance’ is advocated here. Cairbre is invited to act in such a way that he neither too hard nor too soft with each of his qualities of character. It must be noted that the ancient Druids lived in a tribal warrior society, and some of their ethical values make the most sense only within such a society. But in the best philosophical spirit of their predecessors, contemporary Druids are making their own study of ethics and social values. They draw upon ancient sources such as the Greek, Roman, and Irish texts here mentioned, as well as on various more recent sources, and of course their own intellectual and emotional insights. The Order of Bards Ovates & Druids has its roots in the 18th and 19th century revival of Druidry. Its founders were strongly influenced by Neoplatonism, Freemasonry, some forms of liberal Christianity, and the like. Classical sources concerning ancient Druidry and Celtic culture were becoming available. Yet the founders of British Druidry were looking to find, as well as to create, an indigenous British spiritual literature. At the same time, a few serious studies of Britain’s Neolithic monuments were being published by eminent scholars, many of which attributed the design and construction of such monuments to Druids. As early as 1689, the antiquary John Aubrey published his thesis that the Druids were the architects of Stonehenge and Avebury, and he speculated that the Druids must therefore have been in possession of great mystical knowledge. Some of the writers from this time were keen to portray Druids as proto-Christians. On the basis of the remarks by classical writers concerning the Druidic teachings, the early revival druids came to believe that the ancient Druidic moral doctrines were essentially the same as those of Christianity. For instance, Godfrey Higgins, in the year 1829, translated the word Tara, the name of Ireland’s ancient capital, as “the Tora of the Hebrews” (cited in Matthews, ed. The Druid Source Book, pg. 167. By the way, the word Tara really means ‘wide view’ or ‘spectacle’). The revival of Druidry in Britain was also deeply tied into many public values. It attracted social reformers, activists for various causes, labour organizers, socialists and a host of other wonderful and strange people. Contemporary Druids, of course, possess better-quality historical, linguistic, and archaeological information about Druids, and about the Neolithic monuments of Britain and Ireland. But they have inherited from this early revival a number of important spiritual ideas, especially including: the unity and one-ness of the world, the immortality of the soul, the presence of ‘Awen’ (magical or divine inspiration), the experience of the divine in trees and landforms and in nature generally, and the inherent goodness of human nature. Finally, a number of twentieth and twenty-first century Druids have written extensively on Druidry and ethics. In his chapter on Ethics and Values, Philip Carr-Gomm noted that “most Druids have a highly developed sense of ethical behaviour, which is usually implicit in their actions, rather than explicitly stated.” (What do Druids Believe? p. 60) On the basis of his many years of observation, he identified four specific Druidic ethical concepts: responsibility, community, trust, and integrity. This final value, Integrity, is inherited from both heroic-age Celtic culture as well as from the British Revival of Druidry. It is quickly being recognised as one of the most important of all Druidic values. In the year 2008, two comprehensive books on ethics and values from a Druidic perspective were published, both of which discussed Integrity, among other values. One of which is Living with Honour by Emma Restall Orr, head of The Druid Network. In her text, Honour, linked with integrity, is first explored through its traditional association with social standing and reputation in a tribal society. In her closest analysis, she understands Honour as that which emerges from human, ecological, and spiritual relationships. In her words: Because Paganism is based upon reverence for nature, its religious practice is all about our each and every interaction. Pagans don’t reach for a supernatural deity, a god that exists outside of nature… the focus of their living is this planet, its environment, its ecologies and tribes. How we perceive and treat another – whether that other is a human being, a cat, a beetle, tree or stream – is the foundation of Pagan theology. It is in this crafting of relationship, as a spiritual act, that I place the word honour in order to find its essence. (Living with Honour, p. 128.) Thereafter, Orr discusses Honour as the sum of three specific virtues: courage, generosity and loyalty. Each of these, in her view, are involved in various sacred relationships with other people, one’s tribe, and the Earth as a whole. Much of the rest of her text is then devoted to an examination of how these values can be applied to practical problems, such as medical issues, environmental protection, wealth and poverty, the importance of empathy, and especially the importance of human relationships. Another significant book-length treatment of Druidic ethics is The Other Side of Virtue by Dr. Brendan Myers, a philosophy lecturer from Canada and one of the Order’s Mt. Haemus scholars. His book makes a comprehensive study of the mythology of the Celtic people, as well as the Norse and Scandinavians, the Germans, the Greeks, and other people of the ancient world. Through this study of mythology and history he discerned the world-view of Iron-age ‘Heroic’ societies and state-level ‘Classical’ societies. As he sees it, ethics and virtues emerged as responses to universal problems such as transience, fate, destiny, social and political conflict, and death. Then he makes a close philosophical examination of the results of that study. In his view, ethics is not a matter of obeying rules nor following laws. Rather, he says that ethics is a matter of becoming the sort of person from whom goodness and virtue flow naturally. The Druidic person seeks a good and worthwhile life, and develops in her character the qualities and virtues necessary for such a life. In pursuit of this principle, Myers developed an original philosophical system called ‘The Theory of the Immensity’. The argument has a threefold structure, as Myers describes it: 1. First and foremost, life involves inevitable encounters with events that seem, at least at first, to impose themselves upon you. Fortune, nature, other people, and death itself, are among them. 2. Second, these events also invite us to respond. The response generally involves the development of various human potentials and resources. Some of these are social, such as one’s family and friendship ties, and some are personal and internal, like courage and integrity. 3. And third, that if we respond to these imposing events with excellence, and if the excellent response becomes habitual, they can be transformed into sources of spiritual meaning and fulfillment. This transformation opens the way to a worthwhile and flourishing life. (Myers, The Other Side of Virtue, p. 7) This article has looked at Druidry’s moral and ethical concepts in only the simplest, most introductory way. Among Druids today, there is no universally accepted formal doctrine. As noted by Philip Carr-Gomm, “most Druids are keen to avoid the problems caused by dictating a morality to others”. (Carr-Gomm, What do Druids Believe? p. 59) There is, however, an emerging consensus that Druidic values emerge from our dialogue with each other, with nature, with Deity, and with the flow of Awen in our lives. There is also an emerging agreement that Druidry’s ethical values are character values, and are not rules, dogmas, nor utilitarian calculations. Each major contributor, from ancient times to today, has produced his or her own ‘catalogue of the virtues’. But there are a number of values that tend to appear on most catalogues. Here are a few of them, as discussed by three prominent Druidic writers. In every group I have assembled to talk of Pagan ethics, after the main sources have been unravelled, the answer becomes clear. It is simple: relationship. Pagans find and craft their ethics through the experience of relationships. (Emma Restall Orr, Living with Honour) The Druid will tend to see many of the world’s problems emerging from a refusal to take responsibility and to act for the greater good of the whole. By not taking responsibility for environmental degradation, for example, they see politicians and corporations acting simply for the short-term gains of power and profit… Druidism encourages the taking of individual responsibility – first in our own lives, then in concert with others for our community, and for wider issues that affect the community of all life. (Philip Carr-Gomm, What do Druids Believe?) The call to Know Yourself permits no self-deception. It calls for an acknowledgement of both the fire of the divine within us, and also the earth of mortality upon us. (Myers, The Other Side of Virtue) It is a common experience among people who are aware of the spiritual dimension to find that when they trust in life they find it easier to enter a ‘flow’ which carries their life along with a quality of lightness, joy, and effortlessness, that also keeps them aligned with their spiritual purpose. Of course trust will sometimes give way to its opposite – mistrust and fear – but by believing that life is fundamentally good, that there is meaning and purpose to existence, the spiritual seeker finds it increasingly easy to come back to the position of trust. The more we can trust in life, the more we can encourage this flow. (Carr-Gomm, What do Druids Believe?) Although the term integrity is often used to mean ‘the quality of possessing and steadfastly adhering to high moral principles and professional standards’, its deeper meaning is defined in the dictionary as ‘the state of being complete and undivided. The state of being sound or undamaged’… Used in this deeper sense, integrity becomes a value or quality sought by Druids, just as it is by all spiritual seekers. The spiritual journey begins for us when we sense that we are lacking something. We feel incomplete, and so we begin to strive towards Deity, enlightenment, wholeness. Further along the track we discover that these realities exist within us and that it is only our mind that believes we are separated from them. Slowly, through meditation and spiritual practice, we open to an awareness of our completeness, our wholeness. We find integrity. And from this place of integrity we can act with authenticity, not trying to be someone other than who we simply are. (Carr-Gomm, What do Druids Believe? Pp. 63-4) In the old conundrum “Who is more courageous—the one who feels fear yet acts, or the one who feels no fear at all?” the answer is the one who feels the fear, and yet acts. Someone who doesn’t feel fear when about to undertake something dangerous may be someone who doesn’t fully understand what he is about to do, nor the risks involved to himself or others, nor the likelihood of success… A courageous person aims to benefit others, and benefit the society she lives in, and perhaps future generations too. And courage ultimately benefits its possessor, and not just because the courageous person has less fear. It is an affirmation of the world’s potential for goodness and beauty, and an active will to participate in the world. To be prepared to accept danger, suffering, hardship, and even death in the attempt to change the world is to be most fully courageous, and most sincerely loving. These qualities are, it seems to me, self-rewarding; a worthwhile and flourishing life cannot do without them. (Myers, The Other Side of Virtue) When I say that Pagan ethics are based upon relationship, it is with this perception of nature’s consciousness and energy as the essence that both underlies and connects all of life. As the rain is intrinsically connected to the stream and the sea, so is every human connected to the mud and the wheat, to the water they drink, to the dead and to the children yet to be born. And through every gust of wind into which my breath disappears, I breathe the breath that has been breathed by each fox and roe and mouse in the forest, air that has moved through the leaves of the trees, that spills out into the stillness of dusk in the song of the wren and the call of the buzzard who rides the thermals above us all. (Emma Restall Orr, Living with Honour) And if we are to find within us the willingness to give with generosity, we can look to the need for personal responsibility to guide us: as an integral part of nature, we must retain conscious responsibility for our every action and inaction, understanding the impact our living has upon both humanity and the environment within which we live. We are responsible, in part, after all, for the honour of our race, our species, our nation: for the face of our tribe. (Emma Restall Orr, Living with Honour) Our friends make life valuable and meaningful, and that the things we do together with friends is our most important source of happiness… In a heroic society, by contrast, a person’s social relations are all-important: they help constitute his very identity. Friendship is more than a matter of survival expediency, although it does grant large survival advantages. In times of accident or calamity, one will need friends for help or rescue. One earns the right to call upon this help by being there for others in their time of need. It is in one’s interest, then, to be respectful and cooperative. But the spirit of heroic friendship is intrinsically valuable as well: it is the friendship of those who find in each other a second self. (Myers, The Other Side of Virtue) To live with honour is to face each one of those connections, as awake to the relationship as we can possibly be, engaging with courage in honesty, with generosity and responsibility, with the respect that comes of loyalty. Doing so because we choose to, having questioned, and where necessary challenged, explored and found a path of integrity, in each action we represent our tribe – of family, community, humanity – and thus the moral identity of that tribe. To do so without shame or ignorance allows a deep and vital pride that comes from knowing that we have shared well, in truth and in freedom. (Emma Restall Orr, Living with Honour) The Worthwhile Life Everyone’s life is inevitably bound up with the lives of other people, the natural world, the accidents of fortune, and the transience of existence. All these things figure into of everyone’s life story irrevocably. A spirited person responds to all these things in a life-affirming way. And in that response, she may find within herself a revelation of self-knowledge, and purpose, and happiness… The worthwhile life is an active life. It is characterised by the feeling that the world offers itself to you as a place where your purposes may be fulfilled. Or, perhaps, the world appears as a place which has its own purposes which are being fulfilled in you. For that is how we often experience it. A good dialogue with the Immensity tends to arouse the feeling of being alive, being whole, being most fully ourselves. Indeed, happiness itself is the feeling that life is beautiful and good. (Myers, The Other Side of Virtue) In the end values or principles such as those stated here, with others that are related to them or flow from them can form the basis out of which ethical and moral decisions can be made. Rather than internalising a moral code developed perhaps centuries ago by the ruling religious or political elite, we can develop a strong individual sense of morality and ethics born out of our own inner connection to these values. Blaise Pascal succinctly summarised, in the following triad, the ingredients we need to develop this morality, when he said simply: “Heart, instinct, principles.”
Transfer and apply information in one setting to enrich another. - Write or find a story that describes a special place in the local area. - Use mime to describe the people, animals or landforms through movement. Exaggerate and simplify the movements so that the gestures become easy to see. - Explore different dynamics of the movements – move very slowly, move cery small, gradually make the movements bigger, try the movement as solo, duo, or group. Make dance sequences and experiment with a range of options when seeking solutions and putting ideas into action. - Select your favourite parts of the dance making and develop into sequences that are repeated so that it is the same each time. - Teach the sequence to each group with slight variations. - Choose a series of different sounds or play different pieces of music to accompany the movement. Which suits the mood /ideas of your dance best? - Experiment with facing different directions and travelling to different parts of the room whilst performing your sequence. Explain and justify ideas and outcomes. - What could you call your dance? What kind of costume or set could you make or choose to go with your dance? Why have you made these choices? - How is the movement of the body used to represent your idea/s? - How did the dancers use space and energy to create the ideas/feelings in this dance? - Which elements of dance were used? - What could you learn from watching people and creating sequences based on their movements? - What movements could you learn, and use in a dance, based on everyday activities and other cultural practices? Based on Australian Curriculum, Assessment and Reporting Authority (ACARA) Level 2 & 3 statements from the Critical and Creative Thinking learning continuum for Generating ideas, possibilities and actions; Reflecting on thinking and processes; and Analysing, synthesising and evaluating reasoning and procedures areas. Licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Australia (CC BY NC SA) licence. Accessed 03/06/15.
On the IELTS Writing test, one thing that we must consider is tone. In fact, tone is something that is important whether we are communicating in writing or when we are speaking. Using the correct tone helps to ensure our message is received clearly and in the way we intend. Let’s begin by reviewing the different sections of the Academic and General Training IELTS tests: - Task 1 – a description, summary or explanation of a graph, table, chart or diagram - Task 2 – an essay in response to a point of view, argument or problem Task 1 – a description, summary or explanation of a graph, table, chart or diagram General Training Test - Task 1 – a letter requesting information or explaining a situation - Task 2 – like the Academic test, an essay in response to a point of view, argument or problem. Tone is important for each of the tasks above. Specifically, for both tasks in the Academic test, a more formal tone and style is most appropriate. For the Task 2 essay on the General Training test, the essay may be less formal and slightly more personal. For Task 1 (the letter) on the General Training test, you must consider the purpose of the letter as well as the audience to help determine the appropriate tone. Task-1 General Training Letter When it comes to writing the letter in the General Training test, there are a few things to consider when determining the appropriate tone. Firstly, as mentioned above, you must consider the purpose of the letter. For example, the purpose could be an invitation, an explanation, an apology, a request or a complaint. Secondly, you must consider your audience. For the Task 1 letter, there are different styles of letter. Please note, these styles may overlap, depending on the purpose and the audience. Formal letters – Generally speaking, we use a formal letter when writing to someone in a position of authority who we do not know personally. One example could be a letter to a senior manager, or a government representative about an issue or a concern. Semi-formal letters – We would usually use a semi-formal letter when writing to someone we may know, but who is in a position of authority. One example could be writing to explain a situation to your manager. Another example could be a letter of complaint to your neighbours. In this case, since you are writing them a letter (rather than speaking to them face-to-face), there is a good chance you may not know them very well. Personal letters – We would usually use an informal or personal letter when writing to a friend or a relative. Keep in mind, however, that the purpose of the letter may affect this somewhat. For example, if you are writing to express sympathy due to a death in your friend’s family, you may use a slightly more formal tone due to the reason for writing the letter. Adjusting for Tone-Do’s and Don’ts There are many ways to adjust for tone. Here are a few tips to keep in mind: - DOuse everyday language for a less formal tone. You can use the kind of language we use when speaking. - For example, “Sorry for the trouble”, rather than “I apologize for the inconvenience”. - DO use polite, professional language for a more formal tone. - DO use simpler sentences in informal writing. By doing so, you will be better able to clearly state your ideas. - DO use the following when closing a letter: - For formal letters: Sincerely, Many thanks, Warm regards - For less formal letters: Thanks, Cheers, Love, (only use this with someone you are very close to) - DON’T use contractions in more formal writing. Contractions and exclamation points are only acceptable for a less formal tone. Getting the tone correct is key on your IELTS Writing test. As an IELTS examiner, it is usually very easy to spot when the tone is not appropriate.
Why don't our eyeballs fill up with water when we swim? Category: Biology Published: April 22, 2015 Although the eye's pupil is indeed a hole in the front surface of the eye, this hole is covered in the front by a strong, transparent coating called the cornea and in the back by a fibrous, transparent object called the lens. Also, the space between the cornea and the lens is filled with a gel-like fluid called the aqueous humor. All of these layers form a watertight barrier that seals off the inside of the eyeball from the outside world. Fortunately, all of these layers are transparent, so light can still enter our eyes through the pupils, thereby allowing us to see. To ensure that they are transparent, the cornea and lens do not contain any blood vessels. Therefore, nutrients must flow to these tissues through simple diffusion from the aqueous humor. The layers in front of and behind the pupil do more than keep water out. The cornea, the aqueous humor, and the lens all combine together to act as an optical lens that focuses light into images on the back of the eyeball (the retina). Without these layers, the whole world would look like a non-distinct blur. These layers also seal off the inner eye from microorganisms and dust that could cause infection and damage. Additionally, the inner cavity of the eye is not completely empty. Rather, it is filled with a transparent, gel-like fluid called the vitreous humor. This fluid provides pressure that helps the eyeball keep its shape, much like how filling up a balloon with enough water will help it keep its shape. Even if there were an uncovered hole leading into the eye, the eyeball would not fill up with water when we go swimming because it is already filled with this gel.
When I was a kid I heard that the sky was blue because it was the reflection off the ocean. The light from the Sun, which appears white, is actually made up of all colors of the rainbow, when the light enters the atmosphere the colors can become separated (Imagine looking at light through a prism). We know that bluer light travels in short, tight waves while redder light travels in longer waves. The shorter the wavelength, the more likely the light is to bounce off of an air molecule and become scattered. Blue light is scattered most in our atmosphere. I also heard, when I was a kid, that when you observe a sunset and you see the shift in color from blue to red that you’re actually seeing the sun’s rays being filtered through the pollution. Well, that sounds dismal. It’s also not entirely true. One of the main factors in determining a sunset’s color is the Earth’s atmosphere. The atmosphere is made up mostly of gases as well as some other molecules and particles thrown in for good measure. The most common gasses in our atmosphere are nitrogen (78%) and oxygen (21%). The remaining single percent is made up of water vapor and lots of tiny solid particles like dust, soot & ash, pollen, and salt from the oceans. There are also trace gasses like argon present. Also, depending on where you live, you’ll have to factor in that volcanoes can put large amounts of dust particles high into the atmosphere and pollution can add different gases or dust and soot to the air as well. The atmosphere of the Earth can be thought of like a filter on a camera lens. So let’s put it all together in how light acts in the air surrounding our planet. Light moves in a straight line until it is messed with (be it gas, dust, ash, etc.). Once something interferes and gets in the way of the light wave it’ll scatter that light in different directions. The probability of light to be scattered by a molecule is proportional its wavelength, so shorter wavelengths of light are scattered much more often than longer wavelengths. In the case of air molecules, the molecules are much smaller than the wavelength of the scattered light, this is called Rayleigh scattering.
You are here Debunking the Tragedy of the Commons In December 1968, the American biologist Garrett Hardin (1915-2003) published one of the most influential articles in the history of environmental thought.1 Published in Science, it described a social and ecological mechanism that he called the Tragedy of the Commons. The concept was soon being widely cited in academic circles, as well as by journalists, ecologists, government authorities and politicians. Many saw it as a scientific justification for the state control or (more often) the privatization of resources and ecosystems. Today, our historical perspective and improved understanding show this line of thinking for what it is: a misconception with no concrete basis, skewed by a highly ideological perception of social systems. Green pastures and experimentation The biologist’s reasoning was based on a thought experiment. Hardin cites the example of a pasture jointly owned by a group of herders, where each grazes their cattle. What happens when one herder buys a new cow, and releases it on the commons? Once the animal is fattened, the breeder can sell it and earn a certain amount of money, thus becoming wealthier by +1. But that’s not all: adding another cow implies using a bit more of the grass resources. This means that each bovine has a little less grass to eat and fattens that much less. However—and this is the main point—this negative effect is shared among the cattle, while the sale of the extra cow benefits only its owner, who gains +1 and loses only a fraction of –1. It is therefore in the farmers' interest to add another animal, as their profit is always higher than their loss. As more and more cows are added, the pasture is overgrazed and ultimately ruined. As Hardin explains, even though they are aware of the coming catastrophe, the herders are caught up in an inexorable logic that makes them destroy the resource that they depend on for their livelihood. Right to the brink of disaster, it is still in their best interests to earn more by adding a new animal—hence the biologist's choice of the word “tragedy” to underline the idea of an inescapable chain of events, as in a Greek tragedy. The conclusion is cut and dried: communal ownership of a resource is inimical to its sustainability. To avoid its destruction, Hardin insists, there are only two solutions: either divide it into individually owned lots or turn its management over to a higher authority. The only options are private property or the State. State against private property The impact of this argument was far-reaching. Economic thought strengthened this influence by associating the expression “tragedy of the commons” and the image of the pasture with analogous but more sophisticated scenarios in microeconomics and the economy of “externalities.” One of the reasons for the appeal of Hardin’s analysis, at least at first, was its “either-or” conclusion. It can be cited both by partisans of government intervention and by those who favor an open market. However, with the rise of neoliberalism as a school of thought and a sociopolitical force, the “tragedy of the commons” was rapidly reduced to an argument in favor of private ownership. In the 1980s and 1990s, Hardin’s pasture story was popular among US government administrations, international institutions and companies promoting privatization and free-market environmentalism. The reasoning was applied to forest resources, water catchments and farmland, as well as the atmosphere and oceans, to which the logic of appropriation is extended through privatization or the creation of usage rights markets. A historical and conceptual error At the same time, those decades also witnessed a complete overhaul of the scenario, which had been called into question from the word go. First of all because it is based on a highly unlikely behavioral model. The reasoning holds only if one presumes that the herders' sole motivation is individual interest, limited to financial gain. Moreover, it implies that the breeders are unable to speak, as they seem incapable of communicating to regulate the use of the pasture. This is in fact a gross historical and conceptual error on Hardin’s part: he is confusing what he calls the “commons” with open access situations in which everyone can use a resource at will. Yet the term designates something else entirely: the institutions through which communities around the world have managed—and continue to manage—shared resources, often quite sustainably. This can mean pastureland, but also forests, fields, peat bogs, wetlands, etc., that are in many cases vital to their survival. The “Tragedy of the Commons” denies the effectiveness of these organizations, associating good management only with the state or with privatization. Since the 1970s though, the social sciences have empirically documented hundreds of cases of communities past and present that sustainably manage their resources as communal property. The political economist Elinor Ostrom (1933-2012) won the 2009 Nobel Prize in Economic Sciences for her study of rule systems for the organization of such “commons.” Hardin’s reasoning is now outdated—which does not prevent it from being perpetuated in certain media, militant or political circles. A Malthusian concept Since its publication in 1968, the underlying goal of Hardin’s article has also been overlooked. Its author was a biologist, but above all a fervent advocate of neo-Malthusianism. His paper was primarily intended to condemn the urge that causes people to reproduce indiscriminately, to the point of depleting their natural resources. In his metaphor, the animals that the herders keep adding to the pasture are also their children, who take an ever-greater share of the community’s assets. In this case as well Hardin suggested two solutions: either state control over human reproduction or the creation of “birth rights” that could be monetized and traded—a combination of state coercion and market ideology characteristic of the Cold War thinking that was the (so-called) “tragedy of the commons.” The analysis, views and opinions expressed in this section are those of the authors and do not necessarily reflect the position or policies of the CNRS. - 1. Fabien Locher, “Cold War Pastures. Garrett Hardin and the ‘Tragedy of the Commons’,” Revue d’Histoire Moderne et Contemporaine, 60(1), 2013, pp. 7-36
This web portal feature is hosted and managed by Independence Hall Association, owner of ushistory.org. It was undertaken with the erection of the Catto Memorial at Philadelphia City Hall. Dedicated in September 2017, the memorial is the first public monument in Philadelphia on public lands honoring an African American, Octavius V. Catto. When the Constitution was ratified, not all persons in the United States were considered citizens. Citizenship was contentious in America, despite the promise of liberty and equality in the Declaration of Independence. The Civil War marked an important turning point for the expansion of both citizenship and the way the world and Americans viewed immigration and American citizenship. Like every person, O.V. Catto was shaped by his environment and people around him. The timeline here places Catto within the context of his life-shaping environments and events leading up to the birth of Martin Luther King. This extends the story out to the American Civil Rights story into the early 20th century. The education resources here are grounded in “responsive teaching” pedagogic approach. It integrates academics with students’ social-emotional needs and skills to create an environment where students can do their best learning regardless of classroom settings. Also featured are:
Why Music Education for All Students? - Students experience artistic ways of thinking about and expressing the world around them - Nourishes the process of learning which includes: - Sensory integration - Critical thinking - Emotional maturity - Motor capacities - Engages the left and right brain - Builds and strengthens connections between brain cells - Improves memory and the ability to differentiate sounds and speech - Develops critical thinking and leadership skills - Fosters self-esteem and the ability to work cooperatively in teams - It is FUN!!! All Great Valley Academy students in grades kindergarten - 6th participate in music instruction. Students in 7th & 8th grades may participate in music through elective coursework.
This course explores technologies that support language development as well as academic achievement for K-12 English language learners. Emphasis is on technologies that support English language development and communication skills, such as dedicated software programs, websites, and other technology resources. In addition, participants will learn how technologies that were developed for other purposes, such as word processing, can be used in targeted ways to promote English language development. Participants will benefit from numerous resource links for improving English Language Instruction through the use of technology. - Provide a rationale for using language learning technologies to support ELLs' English language development and academic achievement in English. Explain the role of input, interaction, and output in learning second languages. Describe the principles of content-based instruction for language development. - Identify the major phases in the field of language learning technology, or CALL. Identify the major CALL organizations and their resources and evaluate software for functionality and content. - Describe various technologies that support content-based instruction, including native language resources and resources that provide suitable input, interaction, and output for learning and demonstrating mastery of content, depending on the learner's level of English proficiency. - Describe various distance learning technologies and how they might be applied to teaching ESL, including course management systems (Blackboard, Moodle) and integrated online courseware (Elluminate) - Identify quality indicators for distance learning programs, pedagogical principles for engaging distance learning courses and various distance learning resources - Describe computer-mediated communication that facilitate language learning including, videoconferencing, instant messaging, bulletin boards, e-mail and social networking sites. This online course is experiential and interactive. Participants will engage in a variety of activities to learn, practice, and apply the skills outlined in the course. This will include workbook exercises, short answers that are reviewed by a moderator, quizzes, observation and analysis of lessons, coaching interactions with a coaching partner that include feedback and analysis of both the lesson and the coaching episode. A final exam is also a part of the course. Participation in all of these areas is necessary for students to successfully complete the course with a passing grade. Upon completion of the course, students can decide if they would like to receive credit and from which university they would like to receive credit. Please see University Affiliations under the Information Center for the cost per credit. - 1.a Building an instructional framework for language learning technologies - 1.b Learning a Second Language: Critical Elements - 1.cInput, Interaction, and Output: A Closer Look - 1.d Content-Based Instruction - 1.e How Instructional Technology Supports Ideal Learning Conditions for ELLs - 1.f Supplementary Material - 2.a What can teachers of ELLs do with Language Learning Technologies? - 2.b Using LLT's During Classroom Instruction - 2.c Using LLT's to Supplement Classroom Instruction - 2.d Using LLT's to Complement Classroom Instruction - 2.e Using LLT's for Self-Directed Study - 2.f Supplementary Material - 3.a Which comes first, the technology or the teaching? - 3.b Multiple Intelligences and Learning Styles - 3.c Language Learning Pedagogy Part 1: Instruction SLA - 3.d Language Learning Pedagogy Part 2: Naturalistic SLA - 3.e Putting It All Together - 3.f Supplementary Material - 4.a How do I judge the quality of a language learning technology? - 4.b Sources of CALL Software Evaluation Criteria - 4.c Technology Features of Instruction Software - 4.d Content Features of Instruction Software - 4.e Content of CALL Software and Web Resources - 4.f Supplementary Material - 5.a Developing Oral Proficiency Skills: Listening Part 1 - 5.b Developing Oral Proficiency Skills: Listening Part 2 - 5.c Developing Oral Proficiency Skills: Speaking - 5.d Developing Oral Proficiency Skills: Pronunciation - 5.e Developing Vocabulary - 5.f Supplementary Material - 6.a Developing English Reading Skills, Part 1 - 6.b Developing English Reading Skills, Part 2 - 6.c Developing English Writing Skills - 6.d Developing English Grammar skills - 6.e Comprehensive ESL Programs - 6.f Supplementary Material - 7.a Exploring Differentiated Instruction - 7.b Content-based Instruction and Authentic Materials - 7.c Sheltered Instruction and the SIOP Model - 7.d Teaching content to ELLs in Mainstream Classes - 7.e Heritage and Native Language Instruction - 7.f Supplementary Material - 8.a Presentation and Communication Tools - 8.b Interactive Tools - 8.c Word Processors and Desktop Publishing Tools - 8.d Web Page Editors and Wikis - 8.e Blogs and Podcasts - 9.a Teaching and Learning Resources - 9.b Nutta's Principles of Dynamic Distance Learning - 9.c Course Management of Programs for Distance Learning - 9.d Distance Learning for ESL - 9.e Blended Courses for ELLs - 9.f Supplementary Materials - 10.a Computer-mediated Communication - 10.b Synchronous CMC - 10.c Asynchronous CMC - 10.d Using CMC to Develop Writing and Speaking Skills - 10.e Internet Safety - 11.a Distance Communication and Learning Technologies - 11.b Training, Support, and Resources for Instruction Technology - 11.c General Teaching Resources - 11.d Course Management Systems - 11.e Grading Programs - 12.a Language labs - 12.b Guidelines for Integrating LLTs into Instruction - 12.c Checklist for Incorporating LLTs - 12.d Diverse Classroom Contexts - 12e. Summary and Review - Final Exam
The Southern economy during during Reconstruction was in very bad shape because of the Civil War. The war had had many negative effects on the Southern economy. Farms and plantations were in disarray and often ruin. Some had been burned to the ground. Many of the railroad tracks (and there weren't many to start with) had been destroyed. Many towns were in ruin. There was also the question of how would the South be rebuilt? Many former slaves were hoping to obtain some of the land they had been forced to work on without pay, and make their living off of small farms. However, many of the white plantation owners were hoping to bring back a system very similar to slavery in which African Americans would continue to work for them for very little pay.
While it is popularly believed that evolution occurs through mutations in DNA, that's simply not true. Now scientists have more evidence that evolution functions even among proteins that have no DNA. Infectologists at Scripps Institute discovered this evolutionary behavior by studying the behavior of prions, a type of protein you may know because mutated prions in the brain cause mad cow disease. What the researchers discovered was that when they moved prions from brain cells to a new environment, the proteins changed. The prions best-suited to the new environment were slightly different from those that succeeded in brain cells, and those came to dominate the population. When the prions were moved back to the brain cells, however, the prion population shifted back. According to BBC News: Charles Weissmann, head of Scripps Florida's department of infectology who led the study, said: "On the face of it, you have exactly the same process of mutation and adaptive change in prions as you see in viruses . . . This means that this pattern of Darwinian evolution appears to be universally active. In viruses, mutation is linked to changes in nucleic acid sequence that leads to resistance. Now, this adaptability has moved one level down- to prions and protein folding - and it's clear that you do not need nucleic acid (DNA or RNA) for the process of evolution."
Responding to Cyberbullying Cyberbullying is a growing problem that affects almost half of all U.S. teens. Many adults are unaware of the problem and schools are often unsure how to respond to cyberbullying activities. The Anti-Defamation League is responding to the problem through educational programs and advocacy, including: \|“One day this girl I considered my friend started sending me instant messages, calling me names and making fun of me because I had lost my right leg in a car accident as a child growing up in Peru. She even set up an online profile for me: ‘Name: spic. Location: border hopper. Gadgets: peg leg.’ I tried to protect myself, pretending like I didn’t care, but on the inside I was falling apart.” High School Student Most young people today consider e-mailing, text messaging, chatting and blogging a vital means of self-expression and a central part of their social lives. But an increasing number of youth are misusing online technology to bully, harass and even incite violence against others. Cyberbullying, described as intentional harm inflicted through electronic media, affects almost half of all U.S. teens. It is often motivated by prejudice and hate, and some of the most serious cases of cyberbullying are the result of bias based on the target’s race, religion, national origin, sexual orientation and the like. Whether cyberbullying is related to identity-based group membership, however, or more universal characteristics such as appearance or social status, online social cruelty can produce devastating consequences for the targets and may be a precursor to more destructive behavior, including involvement in hate groups and bias-related violence. As a leading provider of anti-bias training and resources, the A WORLD OF DIFFERENCE® Institute offers innovative programming to help schools develop a comprehensive approach to prevent and intervene against cyberbullying as part of a broader strategy to create safe schools for all students.
DNS Records contains the data that will be returned to the client when the client requests information from the server about hosts or resources on the Network. There are lots of DNS records but we will look at the most common ones. Start Of Authority (SOA) : A start of authority (SOA) record is information stored in a domain name system (DNS) zone about that zone and about other DNS records. A DNS zone is the part of a domain for which an individual DNS server is responsible. Each zone contains a single SOA record. It is the DNS Server which has the most authority to make changes in the Domain. It contains the following : - Primary Name Server - Email of Administrator - Domain Serial Number : This tells other DNS Zones which version of DNS Zone that server contains. When changes are made to the Zone, the Serial Number will increase. - Check the SOA records of any website here. Host ( A & AAAA) : - This Record maps the Domain Name to IP Address. - A records are used for IPv4 addresses. - AAAA (Quad A) record is used for IPv6. - Check AAAA Records here. Alias (CNAME / CANONICAL) : To help with administration, DNS allows to create an Alias Record called a CNAME. - CNAME points to A or AAAA (Quad A) Record. - When you attempt to Resolve a CNAME record, the corresponding A or AAAA record is returned. - You can also change the destination with CNAME is pointing to in case you use new server. - It saves from lot of re-configuration headaches on your network when things get change. - Check CNAME Records here. SRV (Service) Records : Originally DNS was designed only to resolve hostname to IP addresses, since then it has expanded to allow users to find resources and services on the network. - A Service Record allows a client to locate services on the network using DNS. - Service Records are used by Active Directory to allow a client to locate a Domain Controller, this is why DNS is so important in windows environment. MX ( Mail Exchange ) Records : - When you attempt to send an e-mail, the e-mail server will read the MX Records for that domain. - Each MX Record has a priority / preference. - The lower priority MX Records are tried first. - If the e-mail server can’t connect to the server with lowest MX priority, it will try the next one. - Check MX Records here. Name Server (NS) Records : Name Server Records are saved with your Domain Name Company. - NS Records are used to set your Name Servers. - NS Record will tell you where to find Name Servers for your Domain. - Mainly there are two : Name Sever, Backup Name Server. - NS Records -> Name Server -> DNS Records - Name server holds DNS Records, it tells the Internet where to find your website/webapp. Pointer (PTR) Records : There are other DNS Records types but PTR Records are the main types. - PTR stands for pointer record. - It maps an IP address to a name. - You must create Reverse Lookup Zone for PTR Records. - Reverse Lookup Zone are used for troubleshooting tools such as TRACERT and NSLOOKUP. In Old days, you had to update your DNS Records manually. With Windows server 2000 came the ability for clients to update their DNS dynamically. This is controlled by the service, DHCP client. To force an update of a client DNS record : - Open Command Prompt with ADMIN privileges. - Type command “ipconfig /registerdns”. Note : With Dynamic Updates, you can also configure it to use Secure updates. This stops a hacker inserting their own records in DNS Server and redirecting user to the Hacker’s Server. And to use Dynamic updates, the client must be a Windows computer and be in windows domain. If you have any query regarding DNS Records, please leave your comment below in comment section.
(1740–1826). A Lutheran pastor and philanthropist, Johann Friedrich Oberlin dedicated his life to improving living conditions in his poor parishes in what is now the Alsatian region of France. He provided his parishioners with educational and economic opportunities in addition to spiritual guidance. Oberlin was born into a middle-class family on Aug. 31, 1740, in Strasbourg, France. He studied theology and graduated from the University of Strasbourg in 1758. He was a teacher until he became a pastor in 1767 in the village of Walderbach, which became the center of his life’s work. Oberlin provided village schools and thus began one of the first systems for supervising and instructing very young children while their parents were working. His teaching methods tied instruction closely to practical needs. In many ways his work foreshadowed that of the German educator Friedrich Froebel, the originator of the kindergarten. Oberlin’s methods won him the respect of adults, who also came to him for instruction. Among them he found men to build roads and bridges to end the isolation of their region. To promote better crop production, Oberlin encouraged experiments in improving crops and started meetings for the exchange of agricultural information. He also made possible the purchase of modern farm implements, bought in bulk and sold at cost, and financed their purchase through a bank that he founded. After subsidizing young men to learn crafts in Strasbourg, he established factories for local industries. Though a Lutheran, Oberlin welcomed Calvinists and Roman Catholics to his communion services. In the 1780s he enthusiastically supported the French Revolution, and he was honored by both revolutionary and imperial governments of France. He died in Walderbach, Bavaria, on June 1, 1826. Oberlin’s name was given to the town and college in the U.S. state of Ohio as well as to the Oberlinhaus, a German center for treatment of the deaf and blind.
You’ve noticed the recent time change- it’s light on your way to work, but the sky quickly fades to black by the time you leave. Many people blame bad moods and symptoms of depression on the decreased amount of daylight, saying, “Oh, I have Seasonal Affective Disorder.” But do you really know what Seasonal Affective Disorder entails? Seasonal Affective Disorder, or SAD, is a form of depression associated with late autumn and winter and thought to be caused by a lack of light. It’s estimated to affect 10 million Americans, with another 1-2 million Americans suffering from a mild form- making it extremely common, affecting 1 in every 30 people in the U.S The term Seasonal Affective Disorder has been around since 1985, and it’s more common the farther North you live; for example, its prevalence is 9.7% in New Hampshire but only 1.4% in Florida. SAD typically starts around age 20, and it’s more common in women than in men (60-90% of SAD sufferers are women); however, men usually show the most severe symptoms. While there is no specific diagnostic test for SAD, people can track their history of seasonal depressive episodes to determine if they have it. SAD has been noticed to run in families, meaning a genetic component is likely. Researchers believe that SAD affects the brain because of a lack of exposure to light, as well as low vitamin D levels in the blood. 55% of SAD patients report a close association with a severe depressive disorder, while 34% reported a close relative abusing alcohol. Since there isn’t very much research around SAD, many myths about the disorder are prevalent. For example, many people who believe they’re suffering from SAD may only be experiencing the winter blues, a milder depression that’s usually treatable by being more active. Psychologists have also posited that people experience SAD symptoms because they associate colder weather seasons with a traumatic event or having to limit activity because of the weather. While true cases of SAD are somewhat rare and the disorder is tough to diagnose, SAD is a serious depressive condition that’s recognized by professionals as a legitimate mental disorder. However, SAD doesn’t entail suffering from other depressive conditions, such as clinical depression or bipolar disorder. With SAD, you ONLY experience depression seasonally and must have had depressive episodes during the last two consecutive winters. Another myth is that SAD only occurs in the winter and that its sufferers are sad the entire winter. In fact, a less common variety of SAD occurs in the summer and is associated with episodes of mania and extreme violence; SAD is also a possible cause for the increase in suicides that typically come with the arrival of spring. SAD isn’t limited to winter only, as it typically starts in fall or winter and improves in spring. Standard symptoms of SAD include fatigue, irritability, trouble concentrating, depression, poor sleep, decreased activity level, overeating and weight gain, and loss of sex drive. To improve symptoms of SAD, daily phototherapy is often prescribed- but it does have temporary side effects, such as headaches, eyestrain, nausea, and insomnia. Doctors might also recommend relocation to a better climate or therapy. At Yellowbrick, emerging adults find their way home. If you or someone you know could benefit from the community-based treatment programs available at Yellowbrick, please contact Yellowbrick today at 847-869-1500.
(Natural News) Nature emits carbon dioxide (CO2) as part of many different natural processes. Plants are known to take them in as a necessary ingredient in photosynthesis, and it benefits the Earth in a lot of different ways, such as accelerating plant growth and food production. Although the planet’s CO2 levels are currently near record lows throughout history, there is still plenty of it to go around, since humans contribute to CO2 emissions as well. But while CO2 may be beneficial to the environment, there is evidence to support the notion that human CO2 emissions could be more useful if converted into other things like carbon monoxide (CO) instead. Now a team of scientists may have finally found a working solution to this issue. A report on the newly formulated method noted that it was developed by researchers at the U.S. Department of Energy‘s (DOE) Brookhaven National Laboratory (Brookhaven Lab). It is said that they were able to find a new electrocatalyst that has the ability to convert CO2 to CO efficiently. The researchers shared the details of their study recently in the journal Energy & Environmental Science. According to Eli Stavitski, one of the scientists at Brookhaven Lab and an author on the paper, it is well-known that there are many ways to use CO. “You can react it with water to produce energy-rich hydrogen gas, or with hydrogen to produce useful chemicals such as hydrocarbons or alcohols,” he explained. “If there were a sustainable, cost-efficient route to transform CO2 to CO, it would benefit society greatly.” By using conventional methods of trying to convert CO2 to CO, scientists found that traditional catalysts just aren’t very effective. And it is said that the main reason for this is the presence of a competing reaction, which is called the hydrogen evolution reaction (HER). It ends up taking precedence over the CO2 conversion reaction, so any attempt to initiate it ultimately fails. There are ways to prevent HER from happening, and thereby convert CO2 directly into CO, but they require the use of so-called noble metals like gold and platinum. These are indeed quite effective, but in practice can be very expensive. The researchers found a breakthrough by using single atoms of nickel in place of these noble metals. Haotian Wang, a Rowland Fellow at Harvard University and a corresponding author on the study, stated, “Nickel metal, in bulk, has rarely been selected as a promising candidate for converting CO2 to CO.” And one of the reasons for it is that it performs HER quite well, and even reduces the rate of CO2 conversions dramatically seemingly at random. “Another reason is because its surface can be easily poisoned by CO molecules if any are produced,” he added. And so the method devised by the researchers relied on single atoms instead. “Single atoms prefer to produce CO, rather than performing the competing HER,” said Stavitski, “because the surface of a bulk metal is very different from individual atoms.” The researchers also resorted to using a sheet of graphene to help tune the nickel atoms as catalysts and suppress HER. They scanned an electron probe over the sample in order to visualize discrete nickel atoms on the graphene sheet properly. As of this time’s writing, the scientists have concluded that their method is indeed an effective way of converting CO2 into CO, and that it is a major step forward for recycling the gas for usable energy and chemicals. Their next act is to apply their findings in the real world, first by finding a way to scale their method of using their single atom catalyst while improving its efficiency and performance all at the same time, bringing back the natural order of things. Read more about carbon dioxide-related issues at CarbonDioxide.news.
Definition - What does Asperity mean? An asperity is a rough portion of material. Even when materials are polished very finely and appear to be completely smooth, they still have asperities at the microscopic level. The size of an asperity has a very strong effect on the way the material behaves when placed into contact with another material, and can contribute to thermal or electrical constriction resistance. Large asperities can also increase the risk of corrosion. Some substances can be trapped in the recesses of the asperities. If the substances trapped happen to be chemically reactive, they can cause corrosion that starts in the asperity and then propagates throughout the material until failure occurs. Corrosionpedia explains Asperity Asperities are always present on any material; therefore none are completely free of asperities. If a material were completely free of asperities, then the reduction of energy due to friction would be zero. Reducing the number or size of the asperities decreases the friction. When asperities are large and extremely uneven the friction that occurs when an object slides across another object is large. Components subjected to friction such as rotating shafts are often polished to reduce the amount of wear and energy loss. Lubricants can also help reduce the effect asperities have on friction. Asperities also cause incomplete contact to occur among materials, which can result in an increase of resistance between the components. The resistance created by the asperities can be electrical resistance, thermal resistance, or both. Care must be taken when designing electrical circuits or heat sinks to reduce the size or number of asperities in order to ensure that energy loss due to resistance is minimal.
The largest galaxy cluster ever seen in the distant universe has been spotted by an international team of scientists using NASA’s Chandra X-ray Observatory, the European Southern Observatory's Very Large Telescope, and the Atacama Cosmology Telescope in Chile. Researchers have named this cluster "El Gordo," Spanish for "the fat one." It is located 7 billion light-years away from our planet. Galaxy clusters are held together by gravity, and are the largest structures in the universe. Scientists are interested in using these clusters to study mysterious phenomena called dark matter and dark energy, which collectively make up about 95% of the universe. That's right - all the material that we see and know so well is only 5% of the universe we inhabit. Dark matter doesn't emit or absorb light; dark energy is thought to be responsible for the expansion of the universe. The formation of galaxy clusters like El Gordo depends on the amounts of dark matter and dark energy, so it may hold clues to these phenomena. El Gordo is made up of two separate galaxy subclusters that are colliding at several million kilometers per hour, the European Southern Observatory said.
Use these printable worksheets to teach students about percentages. Convert from fractions and decimals to percents, solve word problems, and more. Here are four multiple-step word problems that will require a combination of addition, subtraction, multiplication, or division. Two money questions are included. This file has an answer key. There is always something new and exciting happening at Our Math Worksheets! We are constantly adding awesome new worksheets and printable activities to our website. Make sure to take a peek at the wonderful resources Math Worksheets has added recently! 2-Digit Addition (No Regrouping). The addition worksheets on this page have no regrouping or carrying. Approx. levels: 1st grade, 2nd grade.
As Earth enters the Anthropocene epoch, its biodiversity wobbles on the precipice of disaster—and island species have been hit especially hard. About 80 percent of recorded extinctions have occurred on islands and 40 percent of the world's endangered and threatened species are island dwellers. Researchers say the leading cause of these extinctions is invasive rodents—rats and mice that stowed away on ships, then quickly populated islands where they have no natural predators and often find a buffet of things like eggs and baby wildlife. Whereas there are several ways to clear such invaders, the most effective has been rodenticides. But these poisons can neither be deployed effectively on islands with large human populations nor where residents disapprove of their use. And poisons do not discriminate, killing along with unwanted pests the native species they are meant to protect. But now a controversial new strategy called gene drive offers a brutally efficient solution by introducing genetically modified organisms designed to spread a chosen trait—such as producing infertile offspring—throughout a wild population. Scientists, government officials and other interested parties debated the idea last week at the International Union for Conservation of Nature's (IUCN) World Conservation Congress in Honolulu. “A gene drive works by distorting inheritance in its favor,” says Congress participant and biochemist Kevin Esvelt of Massachusetts Institute of Technology, one of the field's leading researchers. When two organisms reproduce, their offspring naturally have a 50 percent chance of inheriting any particular gene from either parent. A gene drive increases those chances to more than 50 percent. Over successive generations that gene “drives through” a population until most individuals possess it. Gene drives already occur naturally in nearly every species we know of, Esvelt says, and researchers have been dreaming up ways to take advantage of the phenomenon for nearly a century. But now scientists finally have a tool that allows them to harness the power of gene drives more precisely and efficiently than ever: CRISPR–Cas9, the affordable and easy-to-use gene-editing tool that allows scientists to modify an organism's genome with extreme precision. In 2014 Esvelt and others published a paper outlining for the first time the potential ways in which CRISPR could be used for gene drives. “It makes it feasible in pretty much any sexually reproducing organism,” Esvelt says. For example, a researcher could modify a rat genome to contain a broken version of a gene necessary for female fertility, and introduce some of these rats to an island. They would mate with wild rats, and all of their offspring would inherit that broken gene. When those offspring then mated with more wild rats, their offspring would all inherit it as well. Given enough time, the entire female population would become infertile and the rats would die out. “Removing invasive species is almost like hitting an island's reset button,” says Heath Packard, a spokesperson for Island Conservation. The nongovernment organization’s stated mission is to prevent extinctions by removing invasive species from islands. But this is easier said than done. “The size and scale of islands we're attempting is pushing the boundaries of the current technology,” which typically involves using anticoagulant rodenticides, says Karl Campbell, Island Conservation’s project director. Rodents have been introduced to some 80 percent of the world's islands, and Campbell says that current practices are only useful for around 10 percent of them. In researching and assessing potential new strategies, Campbell and his colleagues have made an argument for the use of gene drives on islands. Drive systems could be implemented for female infertility or alternatively to make mice more likely to produce infertile male offspring, and the resulting all-male rodent populations would eventually die out. Such systems could conceivably be used on islands as large as those of New Zealand, which recently announced its intention to rid itself of invasive predators by 2050. Meanwhile, Floyd Reed, a biologist at the University of Hawai'i at Mnoa, has been working on a different kind of drive system called underdominance to prevent the Culex mosquitoes introduced to Hawaii from spreading avian malaria to endangered birds, including the Hawaiian honeycreeper. This technique involves releasing enough genetically modified mosquitoes into the environment until they comprise more than 50 percent of the overall population. Once the population reaches that threshold, natural selection works to favor the modified mosquitoes. Eventually the wild mosquitoes die out, leaving the modified ones in their place. In such a system the mosquitoes could be engineered to be incapable either of transmitting the malaria parasite or of reproducing. So far Reed has established a proof of concept in Drosophila fruit flies, a commonly used model species in laboratories across the world. But establishing an underdominance-based gene drive in Culex mosquitoes in the lab has been slow going. Progress might not even be fast enough to save the honeycreeper. Unless something can be done, he says, “in five years, we'll lose at least another species.” A gene drive solution obviously comes with some serious concerns. Fortunately, an underdominance-based system should make it fairly easy to return future generations to their original, unmodified state by releasing enough wild mosquitoes back into the population. But some of the most powerful forms of gene drives are hard to control or reverse, and without the proper biosecurity mechanisms they could theoretically spread beyond the target population to impact an entire species. “No one should even be building a drive system like this to solve a conservation problem. It's just too early. We don't know enough,” Esvelt says, adding, “I'm probably the foremost scientific critic of gene drives even though I'm a leader in the field.” Reed, too, sounds a careful note. “There is potential, but there are some technologies that we need to be very cautious about,” he says. A group of high-profile international activists including Jane Goodall and David Suzuki released a letter, coinciding with the IUCN meeting, openly opposing the release of what they call “genocidal genes” on ecological and moral grounds. Signatories include Claire Cummings, an author and former U.S. Department of Agriculture lawyer. “The existing regulatory framework cannot in any way intervene in this technology,” she says, adding, “there are some strong moral and ethical issues here, but this is very new. This is a real opportunity for us to ask the right questions.” Indeed, when Esvelt wrote his 2014 paper outlining possible uses for the technology, his team also published a second paper explicitly calling for regulatory reform both in the U.S. and abroad. Arizona State University biologist Jim Collins, who convened a group of experts to explore the potential applications for gene drive technology earlier this year, echoed Esvelt, saying, "we need different arrangements. The [regulations] that are in place right now are not sufficient." Luckily there is still time. Even if field testing gene drives safely was possible, it is at least five to 10 years away. “This is a technology that's going to be tremendously powerful, and any tremendously powerful technology needs to be handled very carefully and developed in the open light of day,” Esvelt says. “But it’s not here yet.”
Explore how changes in our atmosphere are warming up the Earth. Learn how scientists solve mysteries about how climate change is affecting our planet. Special Report on Global Climate Change Impacts in the United States This report, from the U.S. Global Change Research Program, summarizes the science and the impacts of climate change on the United States, now and in the future. Special Report on Climate Change An NSF report on current Earth system science research projects that are attempting to solve the puzzle of climate change. Living in the Greenhouse Explore climate, how Earth’s cycles affect climate, the Greenhouse Effect and greenhouse gases, ancient climate changes, climate events and news. NCAR Weather and Climate Basics Explore more about weather and climate by taking a look at this guide to the basics from the National Center for Atmospheric Research. Climate System Visualizations from NCAR’s VisLab Models of the Earth’s climate system powered by huge supercomputers are the basics for these visualizations that show variations in precipitation and other weather through time. This is a fun site where you can learn about our environment. Click on the Eco-Info tab where you’ll uncover a treasure trove of climate change and environmental topics to explore. EPA Climate Change Kids Site The Environmental Protection Agency has created a website just for kids where you can learn, play games while learning about climate change. Climate at the Exploratorium Learn how researchers study climate change. This site explores our atmosphere, hydrosphere, cryosphere, biosphere, and the predicted global effects of climate change. NASA’s Earth Observatory This site provides information on our Earth’s climate and environmental change through satellite imagery and scientific information. U.S. Global Change Research Program USGCRP coordinates U.S. federal research on changes in the global environment. Climate Change - the Basics An explanation of climate change from the Science Museum in London, England The Intergovernmental Panel on Climate Change (IPCC) IPCC is a group of scientists from around the world, brought together by the United Nations to assess our understanding and the potential impacts of climate change.
Difference Between Frequency and Relative Frequency Frequency vs Relative Frequency The terms “frequency” and “relative frequency” usually turn up when we talk about probability in statistics or in math. Probability is expressing belief that a certain result will occur in an experiment, test, or research. It is used to conclude whether the chance of the probable event is more likely to happen. The probability of an event can be determined by doing a little experiment and computations. Most people use probability in statistics, but some people use this in other areas of study as well. Some of these are in mathematics, science, finance, or even in gambling. In statistics, “frequency” is the total number of times a given result came up in an experiment or study. It is the total number of times an event occurs. So we can say that “frequency” simply means the rate of occurrence. For instance, you are going to execute a test to know the probability of getting a six when throwing a dice. You throw the dice ten times, and the side of the dice with six dots on it shows up three times. The result “three times” is your frequency. Drawing a card from a deck of cards is another way to test probability and to get the frequency that a heart will be drawn. Pick five cards and see how many cards you get that have the heart symbol on it. Let’s say you got three heart cards, then that is your frequency. You can get the frequency immediately after you carry out your experiment without having the need to calculate. On the other hand, “relative frequency” is the term used for the fraction of how many times a result occurs over the total number of tries you did for your study. Unlike frequency that you can come up with it by simply conducting the experiment, relative frequency involves a simple calculation. Let us say that you are conducting a random experiment by tossing a coin, drawing a card, throwing a dice, or picking marbles out of a bag and repeated it “N” times. While doing this you observed the absolute frequency of times a certain outcome turns up. The formula to get the relative frequency is very simple. Relative frequency is equal to the number of times the result occurred over the total number of times the experiment is repeated. For example, you are conducting a random experiment by drawing colored balls from a bag. You take ten balls from the bag, and you observed that the red balls came up five times. In this case, the relative frequency is 5/10 or 1/2 or in decimals 0.5. Another good example is if we are to take samples from a production of computer monitors to see whether they are working properly. We take 50 random samples of the computer monitors to test and find out the relative frequency of defective ones. While conducting the experiment we found out that ten of the said computer monitors are defective. Again we get the relative frequency by dividing the defective computer monitors over the number of samples we tested. So that is 10 defective computer monitors divided by 50 computer monitors tested. We get 10/50 or 1/5 which is 0.2. 1.“Frequency” is the number of times the result came up while “relative frequency” is the number of times the result came up divided by the number of times the experiment was repeated. 2.The frequency can easily be determined by simply conducting the experiment and noting how many times the event you are looking for occurred. There are no computations needed. On the other hand, unlike frequency, relative frequency is determined by using simple division. Search DifferenceBetween.net : Email This Post : If you like this article or our site. Please spread the word. Share it with your friends/family. Leave a Response
The Flipped Classroom Week 5: Science & Math (November 17th - 21st) SCIENCE ROCKS: Unit 3- Biomes of the World Biomes are regions of the world with similar climate (weather, temperature) animals and plants. The Earth has many different environments, varying in temperature, moisture, light, and many other factors. Each of these habitats has distinct life forms living in it, forming complex communities of interdependent organisms. A complex community of plants and animals in a region and a climate is called a biome. Exercise A: Answer the following questions by highlighting the information in your books on pages 99- 103. 1. What determines what kind of biome can exist in a particular region? 2. What caused the destruction of biomes over the past several years? 3. Where are tropical rain forests found? 4. List and explain the four layers of the rain forest. 5. State two adaptations made by trees in the rain forest. 6. In which layer of the rain forest do most animals live? 7. Explain why rain forests are important? 8. How are rain forests beneficial to person who are sick? 9. On page 100, list ten animals that you see in the video. 10.Research- Which biome would The Bahamas fall under? 11. In no less that two paragraphs, answer the THINK question on page 103. Exercise A: Answer the following questions by highlighting the information on pages 104- 105. 1. State some adaptations of animals that live in the deciduous forest. 2. What does the word deciduous mean? 3. Define the term temperate. 4. Name some invertebrates that live in the deciduous forests. 5. Where are most deciduous forests found? Exercise A: Answer the following questions by highlighting the information on pages 108- 111. 1. How much rain falls in the desert annually? 2. Define the term: nocturnal animals. 3. What are some adaptations made by plants and animals in the deciduous forests? 4. What are the main kinds of plants in a grassland? 5. How do grasses help small animals and insects in the grassland? MATH MATTERS: Unit 3- Factoring RECAP: Review the definition of the term multiple. The least common multiple is the smallest multiple that is shared by two or more numbers. The easiest way to find the LCM of two or more numbers is to: 1. Identify the multiples of the given number. 2. Circle the smallest number that is common among the two groups. As you prepare for your unit test, review the following concepts: 1. Prime Numbers 2. Division by Primes ( Factor Ladder) 3. Finding Prime Factors ( Factor Tree) 4. Greatest Common Factors 5. Least Common Multiple 6. Rules of Divisibility Lesson 3: Exponents pg 49-50 A power tells you to multiply a number by itself. Another name for a power is an exponent. The value of the power shows you how many sets of the number to multiply. This way of writing numbers is called index notation. It's time to put everything you learned down on paper. Review the following in preparation for your test on Thursday 20th November. What to Study 1. Finding Factors 2. Greatest Common Factor 3. Least Common Multiple 5. Prime & Composite Numbers 6. Rules of Divisibility Lesson 5: Introduction to Fractions pg 51-52 Home Work pg 328- 329 (graded) Due Monday 24th November A fraction is apart of a whole. The numerator is the top number of a fraction. It tells how many parts are used. The denominator is the bottom number. It tell how many parts there are altogether. A mixed number has a whole number and a fraction.
\|Home * Herman's Photos * Herman's Cross * Herman's Handouts * Articles * Solar System * Milky Way * Constellations * FAQ * Comments Herman's Own Holiday Cards for Sale 26th year summery A portion of the above graphics and text courtesy of the The Solar System The Solar System has 8 planets. Not the 9 planets you grew up with. That's because the International Astronomical Union reclassified Pluto as a dwarf planet in 2006. To qualify as a planet, an object needs to orbit the Sun, have enough mass to pull itself into a spherical shape, and have cleared out its orbit of other material. It's this third requirement that Pluto hasn't fulfilled; it's just a fraction of the mass in its orbit, while the other planets are millions of times more massive than everything else in their orbits. There are now 5 dwarf planets in the Solar System: Ceres, Pluto, Eris, Haumea and Makemake. Dwarf planets are objects that orbit the Sun and have enough mass to form a sphere, but they share their orbit with other objects. And as telescopes improve, more dwarf planets will be discovered. There might eventually be more dwarf planets than planets. The theoretical size of the Solar System goes out as far as the the Sun's gravity overpowers anything else in the region; and this is almost 2 light-years away, nearly halfway to the nearest star. It's thought that the Oort Cloud – a region where the long-period comets come from – extends out to 100,000 astronomical units from the Sun (1 astronomical unit, or AU, is the mean distance from the Earth to the Sun). Most of the mass of the Solar System is the Sun. In fact, the Sun contains 99.86% of the mass in the Solar System. It is 73% hydrogen, so most of the matter in the Solar System is hydrogen, with the remaining amount being mostly helium, oxygen and carbon. Everything else, like the metals and rocks is just a tiny fraction of a fraction of the mass in the Solar System. Since the Earth is constantly resurfacing itself, we can't find out how old it is, but there's another way to find out. Meteorites, which date back to the formation of the Solar System, have been raining down on Earth for billions of years. Scientists have sampled meteorites and learned most are 4.6 billion-years-old. That means that everything in the Solar System formed around the same time – give or take a few million years. All the objects in the Solar System orbit the Sun in a counter-clockwise direction. This matches the theory that the Solar System formed all at once from a cool cloud of hydrogen. As the gas came together, it began to spin, so that the Sun collected in the middle, surrounded by an accretion disk of gas and dust. All the planets and other material in the Solar System formed within this rotating disk. There are a few exceptions, however, like Halley's Comet. Spacecraft from Earth have visited or orbited every planet in the Solar System, and more are on their way to visit some of the dwarf planets. We've explored the Sun, the Moon, and many asteroids. And now some of the oldest spacecraft still active – NASA's Voyager spacecraft – have almost reached the Sun's heliosphere; the point where the solar wind slows down as it bumps against the interstellar wind. The Asteroid Belt Numerous irregularly shaped chunks of rock called asteroids or minor planets orbit the sun roughly between the orbits of Mars and Jupiter. Gravitational perturbations keep these objects from forming a planet due to their orbital energy, instead colliding and breaking apart into dust and smaller bodies. The planets inside the Astroid belt are known as the inner planets, while those beyond are known as the outer planets. There are over 7000 documented asteroids and hundreds more are discovered each year. The total mass of all the asteroids is less than that of the Moon. Many are too small to be detected while others are up to 200 km in diameter. Ponder for a moment that millions of pieces of space debris, ranging in size from a grain of sand to several meters, bombard our Earth's atmosphere every day. A meteor, often known as a "shooting star" or "falling star," is a visible streak of light in our atmosphere. They are caused by meteoroids entering our atmosphere and vaporizing due to ram pressure, not friction, leaving a visible trail of light. Most of the millions of meteoroids that enter the atmosphere are burned up in our mesosphere (about 30 - 50 miles up) and never reach the ground, but some do. Rarely, as in the Great Daylight Fireball of 1972, a meteoroid will travel through our atmosphere and pass out again. These are known as Earth-grazing fireballs. Meteorites are meteoroids that reach the Earth's surface. On rare occasions they can cause severe or even catastrophic damage such as the remote Russian Tunguska event of 1908 where a large section of forest was flattened. The cause was theorized to be an air burst from a meteoroid or comet. Meteor showers are named after the constellation from which they seem to radiate. The showers, or even rarely storms, are caused when our orbit intersects with a field of cosmic debris. On such occasions, numerous meteors enter our atmosphere every minute – their trails lasting only about a second. Comets are icy solar system bodies that originate beyond the orbit of Neptune. Short term comets originate from the Kuiper Belt beyond the orbit of Neptune, while long term comets originate from the Oort Cloud in the outer reaches of our Solar System. A comet’s nucleus is a mixture of ice, dust and rocky particles ranging in size from tens of meters to tens of kilometers across. When a comet gets close enough to the Sun, it interacts with solar radiation and the solar wind to form a visible coma, or thin atmosphere, and often a tail that always points away from the Sun due to the solar wind. The Kuiper Belt The Kuiper Belt (rymes with viper) is a system of thousands of rocky and icy objects orbiting the Sun from beyond Neptune's orbit extending roughly from 30 to 50 AU from the Sun. One astronomical unit, or AU, is the mean distance of Earth from the Sun. It is now considered to be the source of the short-period comets. Occasionally the orbit of a Kuiper Belt object will be disturbed by the interactions of the giant planets in such a way as to cause the object to cross the orbit of Neptune. It will then very likely have a close encounter with Neptune sending it out of the solar system or into an orbit crossing those of the other giant planets or even into the inner solar system. The Oort Cloud In 1950, Dutch astronomer Jan Oort proposed that certain comets come from a vast, extremely distant, spherical shell of icy bodies surrounding the Solar System. This giant swarm of objects is now named the Oort Cloud, occupying space at a distance between 5,000 and 100,000 astronomical units. (One astronomical unit, or AU, is the mean distance of Earth from the Sun: about 150 million kilometers or 93 million miles.) The outer extent of the Oort Cloud is considered to be the "edge" of our solar system, where the Sun's physical and gravitational influence ends. The Oort Cloud probably contains 0.1 to 2 trillion icy bodies in solar orbit. Occasionally, giant molecular clouds, stars passing nearby, or tidal interactions with the Milky Way's disc disturb the orbit of one of these bodies in the outer region of the Oort Cloud, causing the object to streak into the inner solar system as a so-called long-period comet. These comets have very large, eccentric orbits and have been observed in the inner solar system only once.
Water provision remains high on the global development agenda including political commitments such as the Millennium Development Goals (MDG) and associated post-2015 targets. By 2012, the United Nations declared that governments had met the MDG drinking water target to ‘halve the number without access to safe drinking water (defined as access to water from an improved source within 1 kilometre of the household).’ This suggests that some development efforts are working. When your target is only 50 per cent, it is not a surprise that the scale of the remaining challenge is great. Seven-fifty million people, many living in Sub-Saharan Africa, still do not have access to safe drinking water. For those who do have nominal access, water supply is often unreliable and frequently takes more than 30 minutes to collect. And the world is long way away from providing the basic sanitation services needed to free communities from open defecation. Water is central for efforts to improve quality of life for the world’s poorest people. It can support virtuous development cycles and pro-poor growth. In contrast, poor access to water and unhygienic sanitation conditions are likely to explain why some countries such as India have worse child malnutrition outcomes than their income levels alone would predict. In theory, clean drinking water helps combat diseases such as diarrhoea, which kills almost 2 million children aged under-5 each year – six times more children than global conflict. Water can also enable hygienic washing practices which reduce exposure to respiratory infection and parasites like worm infections (which cause malnutrition) and trachoma (which causes blindness). And water poverty is gendered. It is typically women and girls who are subject to the drudgery of carrying water over long distances to the household. This potentially exposes them to musculoskeletal injury and physical attacks, and takes away time that could be more productively spent. What remains at issue, however, is the extent of evidence supporting such claims and the likely size of these impacts. 3ie has produced an evidence gap map that addresses this issue by consolidating what we know about what works in the water, sanitation and hygiene (WASH) sector. The gap map has been developed as a tool that can help policymakers access rigorous systematic review evidence on WASH and assist researchers and funders for determining priorities for conducting future systematic review and impact evaluation research. The results of the evidence gap map are available online and a report will be published shortly. The findings are summarised here. We found, appraised and summarised 137 impact evaluations and 26 systematic reviews examining effects of WASH provision. Evidence from systematic reviews suggests WASH interventions can make a big difference to combating infectious diseases and reducing child malnutrition. Hygiene promotion is probably the most efficacious way to reduce child diarrhoeal disease rates. However, recent impact evaluations, published since the systematic reviews were undertaken, have questioned the scalability of community programmes for promoting hygiene. And reviews of hygiene promotion also need to take into account the role of water supply as an enabling co-intervention more systematically. In contrast, evidence suggests interventions to treat dirty drinking water do not lead to large sustained improvements in diarrhoea because uptake is not sustained and willingness to pay for water treatment is limited. However, most systematic reviews do not attain the status of ‘high confidence in the review findings’. This is often due to the limited nature of searches for unpublished literature and the questionable rigor of many of the included studies. There are also concerns about methods of synthesis, for example where studies have used vote-counting rather than statistical meta-analysis, or, where meta-analysis has been used, more attention needs to be given to examining heterogeneity and grouping interventions appropriately. Many WASH systematic reviews are also simply out of date. In particular, systematic reviews of water treatment interventions need to be updated to include the most recent rigorous evidence from blinded studies which have called into question the reliability of self- and carer-reported diarrhoea data. Although WASH sector researchers have shown long-standing commitment to theory-based impact evaluation, the evidence base remains small, especially for non-health outcomes, as shown in the figure. The figure shows serious gaps in evidence for non-health outcomes. These outcomes are likely to be at least as, if not more, important to quality of life for programme beneficiaries as health outcomes since they are easily observed. In particular, data on productive sector and gendered outcomes are critically under-collected and under-reported. Not a single rigorous impact evaluation has attempted to measure impacts of water and sanitation improvements on women’s and girls’ safety and very few have examined the drudgery involved in water collection and transportation. More studies collecting data on intermediate outcomes like the time used to collect water or access sanitation are also needed to shed light on these factors. The quality of the impact evaluation evidence has tended to be quite low in the past due to lack of rigorous methods, particularly for costly interventions like water supply improvements. Rigorous evidence can help us determine how we can most effectively meet these challenges and improve the lives of the most disadvantaged people around the world. Researchers have shown that it is possible to apply high quality evaluation methodologies, including randomized assignment, to evaluate piped water connection and sanitation impacts. 3ie has already supported several such studies. In partnership with the Water Supply and Sanitation Collaborative Council (WSSCC), 3ie has recently embarked on a programme of research which aims to start filling some of the important research gaps by funding new impact evaluations and systematic reviews. We encourage researchers to look out for a call for rigorous systematic reviews of WASH-sector programmes that will be announced by next week.
At the age of ten, Tsiolkovsky became almost totally deaf due to scarlet fever. Consequently, he spent much time alone, but his father, recognizing his son's potential, encouraged his interests in math and physics. At the age of twenty-two Tsiolkovsky became a teacher, but he also continued to pursue his own experiments in physics and invention. His interests extended to airshi s and he developed the first wind tunnel in Russia to experiment on how much friction a metallic plane could generate at a certain speed. In 1895, he first mentioned space travel in an article that he fully expectednever to be published. It was, however, and thoughts of travel in space began to dominate him. By 1898, he completed a preliminary study of space traveland outlined many of the basic concepts now taken for granted by scientists.He proposed that humans could only enter space in a sealed cabin with oxygenreserves and air purification devices. He also knew that rockets could be theonly means of propulsion in empty space because, unlike conventional engines, they did not rely on oxygen for combustion. Realizing that a rocket powerful enough to carry humans into space needed fuel with a higher exhaust speed,he advocated liquid fuels such as kerosene as opposed to the solid fuels thenbeing tested by engineers. His theories in this regard predated the researchof Robert Goddard. Tsiolkovsky's ideas were initially dismissed by the Russian scientific community. However, following the October Revolution, the Communist government began to look more closely at his work and in 1921 awarded him a pension, allowing him to concentrate fully on his studies. Dr. Jakov Perelman, a writer and editor, helped to popularize Tsiolkovsky's ideas and by the mid-1920s Tsiolkovsky had garnered international attention. He also based a novel, Outside of Earth, on his research, which told of a journey through space, furthering his reputation among the general public. In his later life, Tsiolkovsky was given many honors. His seventy-fifth birthday prompted glowing tributes in Soviet papers and honors from the Communistgovernment. Following his death, the launching of Sputnik 1 was timed to coincide with the one hundredth anniversary of his birthday, but missed by twenty-nine days. Nevertheless, their efforts affirmed Tsiolkovsky's belief that "the Earth is the cradle of the mind, but one cannot live forever in the cradle."
Things were looking up for Earth about 12,800 years ago. The last Ice Age was coming to an end, mammoths and other large mammals romped around North America, and humans were beginning to settle down and cultivate wild plants. Then, suddenly, the planet plunged into a deep freeze, returning to near-glacial temperatures for more than a millennium before getting warm again. The mammoths disappeared at about the same time, as did a major Native American culture that thrived on hunting them. A persistent band of researchers has blamed this apparent disaster on the impact of a comet or asteroid, but a new study concludes that the real explanation for the chill, at least, may lie strictly with Earth-bound events. The study “pulls the rug out from under the contrived impact hypothesis quite nicely,” says Christian Koeberl, a geochemist at the University of Vienna. Most evidence for the extraterrestrial impact hypothesis, he says, was conjured up “out of thin air.” The 1300-year big chill is known as the Younger Dryas, so called because of the sudden worldwide appearance of the cold-weather flowering plant Dryas octopetala. A number of causes have been suggested, including changes in ocean currents due to melting glaciers and volcanic activity. In 2007, a diverse group of 26 researchers, led by nuclear chemist Richard Firestone of the Lawrence Berkeley National Laboratory in California, formally proposed what is known as the Younger Dryas impact hypothesis, in which one or more extraterrestrial bodies blew up over North America, leading to widespread wildfires and strewing sun-blocking dust and debris across the globe. In a series of papers, Firestone and his colleagues claimed various kinds of evidence for the hypothesis, including deposits of the element iridium (rare on Earth but abundant in meteorites), microscopic diamonds (called nanodiamonds), and magnetic particles in deposits at sites supposedly dated to about 12,800 years ago. The notion was popularized in television documentaries and other coverage on the National Geographic Channel, History Channel, and the PBS program NOVA. These claims were sharply contested by some specialists in the relevant fields, however, who either did not detect such evidence or argued that the deposits had other causes than a cosmic impact. For example, some say that nanodiamonds are common in ordinary geological formations, and that magnetic particles could come from ordinary fires. Now comes what some researchers consider the strongest attack yet on the Younger Dryas impact hypothesis. In a paper published online this week in the Proceedings of the National Academy of Sciences, a team led by David Meltzer, an archaeologist at Southern Methodist University, Dallas, in Texas, looks at the dating of 29 different sites in the Americas, Europe, and the Middle East in which impact advocates have reported evidence for a cosmic collision. They include sites in which sophisticated stone projectiles called Clovis points, used by some of the earliest Americans to hunt mammals beginning about 13,000 years ago, have been found, such as Chobot in Alberta, Canada, Murray Springs in Arizona, and Paw Paw Cove in Maryland; the site of Abu Hureyra in Syria, where evidence of plant-cultivating hunter-gatherers occurs; and sites in Greenland, Germany, Belgium, and the Netherlands where other evidence for an impact has been claimed. The team argues that when the quality and accuracy of the dating—which was based on radiocarbon and other techniques—is examined closely, only three of the 29 sites actually fall within the time frame of the Younger Dryas onset, about 12,800 years ago; the rest were probably either earlier or later by hundreds (and in one case, thousands) of years. “The supposed Younger Dryas impact fails on both theoretical and empirical grounds,” says Meltzer, who adds that the popular appeal of the hypothesis is probably due to the way that it provides “simple explanations for complex problems.” Thus, “giant chunks of space debris clobbering the planet and wiping out life on Earth has undeniably broad appeal,” Meltzer says, whereas “no one in Hollywood makes movies” about more nuanced explanations, such as Clovis points disappearing because early Americans turned to other forms of stone tool technology as the large mammals they were hunting went extinct as a result of the changing climate or hunting pressure. Maarten Blaauw, a paleoecologist at Queen’s University Belfast in the United Kingdom, finds the new work convincing. “It is vital to get the ages right,” he says, which “appears to have been lacking in the case of the [impact] papers” that Meltzer and his colleagues reanalyzed. “This paper should be read widely, and its lessons learned by the paleo community and by archaeologists.” But impact proponents appear unmoved by the new study. “We still stand fully behind the [impact hypothesis], which is based on more than a confluence of dates,” Firestone says. “Radiocarbon dating is a perilous process,” he contends, adding that the presence of Clovis artifacts and mammoth bones just under the claimed iridium, nanodiamond, and magnetic sphere deposits is a more reliable indicator that an extraterrestrial event was responsible for their disappearance. Note : The above story is based on materials provided by Michael Balter forAmerican Association for the Advancement of Science.
The sinuous shape triggers a primal jolt of recognition: snake! A new study of the monkey brain suggests that primates are uniquely adapted to recognize the features of this slithering threat and react in a flash. The results lend support to a controversial hypothesis: that primates as we know them would never have evolved without snakes. A tussle with a snake meant almost certain death for our preprimate ancestors. The reptiles slithered through the forests of the supercontinent Gondwana roughly 100 million years ago, squeezing the life out of the tiny rodent-sized mammalian ancestors of modern primates. About 40 million years later, likely after primates had emerged, some snakes began injecting poison, which made them an even deadlier and more immediate threat. Snakes were “the first and most persistent predators” of early mammals, says Lynne Isbell, a behavioral ecologist the University of California, Davis. They were such a critical threat, she has long argued, that they shaped the emergence and evolution of primates. By selecting for traits that helped animals avoid them, snakes ultimately endowed us with forward-facing eyes, for example, and enlarged visual centers deep in our brains that are specialized for picking out specific features in the world around us, such as the general shape of a snake’s body camouflaged among leaves. Isbell published her “Snake Detection Theory” in 2006. To support it, she showed that the rare primates that have not encountered venomous snakes in the course of their evolution, such as lemurs in Madagascar, have poorer vision than those that evolved alongside snakes. “It is a very bold theory,” says Arne Öhman, a psychologist at the Karolinska Institute in Sweden who uses brain imaging and behavior studies to test how humans respond to visual threats. But thus far, he says, there has been little neurobiological evidence for it. Two years ago, neuroscientists at the University of Toyama in Japan and the University of Brasilia in Brazil contacted Isbell, hoping to join her in a search for brain-based evidence. In a paper published online today in the Proceedings of the National Academy of Sciences, the team describes how images of snakes affect the pulvinar—a cluster of neurons in an evolutionarily ancient part of the brain called the thalamus. Pulvinar neurons are believed to help direct our attention using our eyes and recognize a potential threat. Primates have much larger pulvinars than other animals and certain parts of the pulvinar are even unique to primates. According to Isbell’s hypothesis, other mammals that had to contend with snakes were mostly burrowing creatures, and they didn’t rely as heavily on vision as early primates, which rested in trees during the day. While some mammals developed resistance to snake venoms, primates opted for a better detection strategy. To test the snake recognition prowess of the pulvinar, the group inserted electrodes into the brains of two captive-born macaque monkeys who had never encountered the reptiles. They measured the electrical spikes from individual neurons in two regions of the pulvinar while the primates looked at four types of images: snakes both coiled and elongated, macaque faces with both angry and neutral expressions, macaque hands in various positions, and geometric shapes such as circles and stars. They found that images of snakes had a particularly strong and fast-acting effect on pulvinar neurons: Of the 91 neurons that became active at some point in the experiment, 40% were “snake-best,” meaning they were more active during snake photos than other images. These neurons also fired more frequently than the ones responding to faces, hands, or shapes. (Neurons responding to angry faces, an important social threat for the highly social macaques, came in second.) Finally, snake-responsive neurons sprang into action more quickly, activating about 15 milliseconds faster than those that responded to angry faces and about 25 milliseconds ahead of the neutral shape-detecting neurons. Isbell calls these findings “the first neuroscientific support” for her snake-centric evolutionary theory. She suspects that our unique pulvinar makes primates most adept among mammals at recognizing snakes, though she acknowledges that prediction still needs testing. There is some evidence that primates are especially skilled at detecting snakes that aren’t moving, she says, and that ability may underlie another primate-specific skill: using vision to guide reaching and grasping movements. (Example: Reach for a banana, but don’t reach toward a slumbering snake.) The results support the idea that primates have built-in mechanisms for recognizing a very specific threat based on its shape, says Isabelle Blanchette, a cognitive psychologist at the University of Quebec, Trois-Rivières, in Canada who studies the role of emotion in how we process information. But she warns that we should resist the urge to extrapolate to humans. Even if we carry these “leftovers from evolution” in the form of snake-sensitive neurons deep in our visual system, higher brain processes, such as learning and memory, may influence our behavior just as much as this deep and instinctive snake sense. “It’s a very important part of the picture, but it is only a part,” she says. Her research has shown that humans aren’t always faster at detecting snakes than other threats, including guns and cars, which we haven’t evolved to fear innately. ScienceNOW, the daily online news service of the journal Science
Positive reinforcement leads to a lifetime of great habits. Starting as early as the first tooth that pops its little way through is very important! Here are some things to do along with the book Brush Barry Brush to educate your children on brushing. THINGS TO DO: 1. Positive reinforcement. This is achieved through positive feedback by rewarding desirable behavior (brushing). For ex. utilizing the brushing chart and stickers in the book. 2. You can talk about colors and your child can pick out which character they like the best. For ex. Barry and the blueberries. 3. Make up a fun toothbrushing song. Positive reinforcement is as simple as singing together. It works wonders It is fun to for you to sing to them and have them happily brushing. Eventually they learn the words and sing it too. You can make up your own using the child’s name, with rhyming words. The idea is to make it fun! For example , one that I used , was to the tune of “Row,Row Row Your Boat”: Brush , brush , brush your teeth, After eating meals each day, Cleaning ,cleaning, cleaning, cleaning Fighting tooth decay. Another verse could include Brush brush brush your teeth, after eating meals each day, Front , back, take off the plaque, Now we smile all day! 4. As children get older you can have them look in the mirror and count their teeth. Talk about the fact that there are 20 in all- 10 on top and 10 on the bottom. 5. Discuss healthy food choices. Look in the book and talk about what the kids are eating. For example Doreen eats dark chocolate. Then she brushes her teeth. Although it would be best to eat something like that for dessert at a meal, in real life it does not always happen like that! So if you do eat a snack just brush after. If you are away,you can swish some water and swallow and then brush when you get home. The idea is to form the habit cleaning your teeth by swishing water or actually brushing after eating, whenever possible. 6. You and your child clap for each syllable and say: Eat, then brush,eat,brush,eat brush Clean each tooth. Don’t be in a rush O-pen wide, look in-side, smile and say Health -y teeth, hoo-ray, hoo-ray! 7. Show and tell. Role models are important! Parents should be a model for good home care habits and start an educational and motivational program early while the kids are young and eager to imitate. If you want your children to have smiles that will last a lifetime, get them into the habit of cleaning teeth after eating whenever possible. Offering positive reinforcement will encourage them even more. 8. Have your child think of vegetables that begin with the same letter or sound as their name. Then have them draw a picture of themselves eating it and then brushing their teeth.
For those who are new to STEAM education, STEAM learning is EXCITING for kids! It allows kids to discover how the educational disciplines of science, technology, engineering, the arts, and math are interwoven. STEAM activities challenge kids with hands-on opportunities to explore, create, inquire, observe relationships, predict outcomes, and find solutions to problems using interdisciplinary knowledge and critical thinking skills. Wassily Kandinsky’s masterpiece, Squares with Concentric Circles, by name alone, suggests a commonality. When applied to STEAM education, concentric circles provide a perfect analogy to represent how various learning disciplines share common knowledge to enhance educational experiences for kids. KANDINSKY-INSPIRED WOVEN CONCENTRIC CIRCLES Objective: to invite kids to explore Kandinsky’s Concentric Circles through physical woven construction and within the framework of STEAM learning. STEAM Concepts Presented: Science: The discovery of concentric circles found in our world. Technology: The use of technology to enhance and document learning. Engineering: The construction of physical woven concentric circles that exhibit attempts at architecture and engineering. Arts: Construction of the woven concentric circles that encourage the student artist’s creative expression. Math: The exploration of lines, patterns, and the construction of concentric circles that share the same center. Kandinsky Background Information: Show the Power Point (linked here) to the students and invite them to look at the concentric circles painting in the presentation. Ask students about what they find in the painting: What commonalities do they see in the picture? What is different about the circles? Concentric circles share a center point – do the circles in the painting have a common center? What colors did the artist choose for the painting? Remind children that they do not have to like every artwork, but they must always be respectful of the artist. Invite the students to weave their own concentric circles with Wikki Stix! Weaving the concentric circles is not only a fun way to re-create the painting, but the skills presented in the physical woven construction have been a basis for woven fabric (and other materials) engineering and architecture for thousands of years. Materials needed: Assorted Colors of Wikki Stix Directions: Invite the kids to make a star pattern using 4 Wikki Stix (see photo). Using a separate Wikki Stix, have the kids start at the center and then weave the strand over and under each Wikki Stix in the star pattern to form the inner circle. The kids should continue using additional Wikki Stix to weave a concentric circle pattern around the center until the circle is the desired size. When finished weaving, kids can simply tuck any length of Wikki Stix remaining behind the circular design. Wikki Stix will adhere behind the constructed circles without the need for glue or tape. As the kids finish their woven concentric circles, the circles can be mounted on heavy paper (or strung from the ceiling) and displayed at home or in the classroom. Extension Activities with Concentric Circles Invite kids to experiment and look for concentric circles found in their world. When kids are aware and begin looking, they will find concentric circles are everywhere! Some examples: CD’s, the Target store Logo, archery or other targets with a common center, ripples made in the water after tossing a pebble, the growth rings in a tree, an onion’s rings, circular patterns on a peacock’s feathers, patterns on a butterfly’s wings, the hubcap on a wheel, the human eye, Saturn’s rings, hurricanes, tornadoes, and rings made from various light sources (such as a flashlight). Digital Documentation of Learning Have the kids take photos of their Wikki Stix artwork, concentric rings they find on field trips, in nature, in the classroom, at home, on a walk, or in the night sky! To create the trailer shown, our kids took digital photos and loaded them into an iMovie Trailer template. The kids had great FUN, but they also gained awesome technology skills along the way! Concentric circles occur often enough in our world to rule out possibilities of coincidence. When kids are exposed to the concept of concentric circles through STEAM learning, they gain knowledge to begin formulating ideas about how their everyday world is connected to a larger universe. For more STEAM Education Ideas with Wikki Stix, please visit:
From How Gold Works: Removing a gold-bearing rock from the ground is just the first step in extracting gold. To isolate pure gold, mining companies use a complex extraction process. The first step in this process is breaking down large chunks of rock into smaller pieces. At a mill, large machines known as crushers reduce the ore to pieces no larger than road gravel. The gravel-like material then enters rotating drums filled with steel balls. In these drums, the ore is ground to a fine slurry or powder. Next, mill operators thicken the slurry with water to form pulp and run the pulp through a series of leaching tanks. Leaching dissolves the gold out of the ore using a chemical solvent. The most common solvent is cyanide, which must be combined with oxygen in a process known as carbon-in-pulp. As the cyanide and oxygen react chemically, gold in the pulp dissolves. When workers introduce small carbon grains to the tank, the gold adheres to the carbon. Filtering the pulp through screens separates the gold-bearing carbon. The carbon moves to a stripping vessel where a hot caustic solution separates the gold from the carbon. Another set of screens filters out the carbon grains, which can be recycled for future processing. Finally, the gold-bearing solution is ready for electrowinning, which recovers the gold from the leaching chemicals. In electrowinning, operators pour the gold-bearing solution into a special container known as a cell. Positive and negative terminals in the cell deliver a strong electric current to the solution. This causes gold to collect on the negative terminals. Smelting, which results in nearly pure gold, involves melting the negative terminals in a furnace at about 2,100 degrees F (1,149 degrees C). When workers add a chemical mixture known as flux to the molten material, the gold separates from the metal used to make the terminals. Workers pour off the flux and then the gold. Molds are used to transform the liquid gold into solid bars called doré bars. These low-purity bars are then sent to refineries all over the world for further processing.
Physical vs Chemical Weathering We see mountains or large rocks stay as it is for years without changing. May be, for hundreds of years, we may not see them changing. However, changes are taking place there which we cannot see because those changes are very small and taking place very slowly. Weathering is such a process that rocks, soils, and any material go through. This is the process by which rocks are breaking down into smaller particles. Due to wind, water, or biota a slow breakdown happens which is known as weathering. There’s no visible movement in this form. After weathering the materials are combined with other organic material and forms soil. The content of the soil is determined by the parent rock which undergoes weathering. Weathering can be divided into two as physical weathering and chemical weathering. Usually both processes are taking place at the same time, and both are responsible for the whole weathering process. What is Physical Weathering? Physical weathering is also called as mechanical weathering. This is the process where rocks breakdown without altering their chemical composition. Physical weathering can occur due to temperature, pressure or snow. There are two main types of physical weathering. They are freeze thaw and exfoliation. Freeze-thaw is the process where water goes into the cracks of the rock, then freezes and expands. This expansion causes rock to break apart. Changing temperature also causes rocks to expand and contract. When this happens over a period of time, rock parts starts to break down. Due to the pressure, cracks can be developed parallel to the land surface which leads to exfoliation. Physical weathering is prominent in the places where there is little soil and few plants. For example, in desserts surface rocks are subjected to regular expansion and contraction due to temperature changes. Also, in mountain tops, snow keeps melting and freezing which causes physical weathering there. What is Chemical Weathering? Chemical weathering is the decomposition of rocks due to chemical reactions. This changes the composition of the rock. This often takes place when rain water reacts with minerals and rocks. Rain water is slightly acidic (due to dissolution of atmospheric carbon dioxide, carbonic acid is produced), and when the acidity increases chemical weathering also increases. With the global pollution, acid rains occur now, and this increases chemical weathering more than the natural rate. Other than water, temperature is also important for chemical weathering. When the temperature is high, the weathering process is also high. This releases minerals and ions in rocks into surface waters. There are three main types as to how the chemical weathering occurs. They are solution, hydrolysis and oxidation. Solution is the removal of rock in solution due to acidic rain water, as above described. This is sometimes called carbonation process, since the rain water acidity is due to carbon dioxide. Hydrolysis is the breakdown of rock to produce clay and soluble salts by acidic water. Oxidation is the breakdown of rock due to oxygen and water. Physical Weathering vs Chemical Weathering - Physical weathering does not change the chemical composition of the rock whereas chemical weathering changes the composition. - Physical weathering may result due to temperature, pressure, snow, etc. whereas chemical weathering mainly takes place due to rain.
Lechatelierite also forms as the result of high pressure shock metamorphism during meteorite impact cratering and is a common component of a type of glassy ejecta called tektites. Most tektites are blobs of impure glassy material, but tektites from the Sahara Desert in Libya and Egypt, known as Libyan desert glass, are composed of almost pure silica, that is almost pure lechatelierite. High pressure experiments have shown that shock pressures of 85 GPa are needed to produce lechatelierite in quartz grains embedded in granite. Lechatelierite was formed during the impact of a meteorite into a layer of Coconino Sandstone at Meteor Crater in Arizona. It was puffed up to more than twice its size by steam and can now float on water.
Written by Bethany Todd, in Collaboration with Laura Barr Brene Brown teaches everyone about courage by redefining it as something more than “heroic”. She defines courage as being honest and open to being yourself, to ask when you need something, and allowing oneself to be vulnerable. As I learn about this kind of “ordinary” courage, my brain keeps thinking about the need to teach this type of courage to our young teens. Young Teens Should Know that It Takes Courage to… - Be yourself - Ask for help - Be honest - Accept a challenge - Be vulnerable - Say “NO” One of the biggest ways in which middle schoolers need courage is in relationships, with their peers, siblings and parents. In a Psychology Today article, Tina Gilbertson sheds some light on this topic; she calls it “relational courage”. Gilbertson states that it takes “grit” to be a real friend and have deep relationships. Friendships are the most important thing to young teens as they enter adolescence and begin to respond to peer pressure. Gilbertson suggests that in order to deepen and “show up” in our relationships, we need to courageously do the following 5 things: - Start tough conversations - Set goals and work toward them, even when failure is possible or even likely - Apologize when necessary - Tell the person who hurt you that they hurt you, and what you want them to do about it - Say No to people What fabulous tools to teach our teens! Quotes to Think about and Discuss with your Middle School Child Dr. Melanie Greenberg, shares quotes about courage in a Psychology Today article. Consider putting them up in the house or asking your child to think about what they mean to her. Have a family meeting or lively family dinner conversation in which you discuss one of these quotes: - Courage doesn’t always roar. Sometimes courage is the little voice at the end of the day that says I’ll try again tomorrow. — Mary Anne Radmacher - When we are afraid we ought not to occupy ourselves with endeavoring to prove that there is no danger, but in strengthening ourselves to go on in spite of the danger. — Mark Rutherford - Courage is about doing what you’re afraid to do. There can be no courage unless you’re scared. Have the courage to act instead of react.” — Oliver Wendell Holmes - I learned that courage was not the absence of fear, but the triumph over it. The brave man is not he who does not feel afraid, but he who conquers that fear — Nelson Mandela - To dare is to lose one’s footing momentarily. To not dare is to lose oneself. — Soren Kierkegaard
IridaceaeArticle Free Pass The Iridaceae contains some 80 genera and an estimated 1,700 species of mostly perennial herbs; there are a few shrubs and evergreen herbs as well. The family is nearly worldwide in distribution, but it is most abundant and diversified in Africa. Most species are native to temperate, subtropical, and tropical regions. Species of Iris, Gladiolus, and Crocus grow best in rich soil. A few irises, however, grow in swampy locations, and a few withstand the rigours of subarctic substrates. In addition to Iris, Gladiolus, and Crocus, the Iridaceae includes ornamental genera such as the blackberry lily, or leopard flower (Belamcanda), a native of China and Japan, and the blue-eyed grasses (Sisyrinchium), which are widely dispersed in the Western Hemisphere. The capsule wall of the blackberry lily recurves at maturity to display shiny, black seeds resembling the fruit of the blackberry. The delicate blue-eyed grasses are attractive plants for naturalistic gardens. Plants of the genus Freesia are widely grown commercially for cut flowers. Members of Iris also yield orrisroot (a substance used in the manufacture of perfumes, soaps, powders, and dentrifices). The feathery stigmas of Crocus sativa yield saffron, which is used as flavouring and food colouring and as a medicinal ingredient. The underground stems of members of the iris family may be one of at least three structural types: rhizomes, bulbs, and corms. In Iris the stem is horizontal, robust, and ringed with leaf-scars. It is a rhizome that often grows partially exposed but is firmly rooted in the soil. Species of Iris native to southwestern Europe produce bulbs. This type of stem is short and conical and from it many leaf bases arise, one inside the other. These bases are seamless and constitute the bulk of the bulb. Bulblets arise from the stem, between the leaf bases, to propagate the plant. The corm of Gladiolus is an underground stem in the shape of a doughnut without a hole. On the concave upper surface a small cluster of leaves is located. Among the leaf bases, cormlets arise to reproduce the plant. Rhizomes, bulbs, and corms are efficient in the vegetative reproduction of the Iridaceae. Reproduction by seeds is also very important in the iris family and is essential in the development of new hybrids. In Crocus only one flower may develop from each corm, but in many other genera, as in Iris and Gladiolus, an inflorescence (flower cluster), sometimes branched, arises from the underground stem. Flowers of the showy garden irises possess three sepals (falls), three petals (standards), and three broad, pollen-receptive stigma branches, under which the pollen-producing anthers are hidden. These flower parts are located above the ovary (inferior ovary), which consists of three carpels unified into a single pistil. Ovules within the ovary portion become seeds, and the ovary matures into fruit. Members of the Iridaceae produce dry capsules, a fruit that splits open to release the seeds. Most plants in the family have long, narrow leaves, generally with parallel venation. Bulbous irises may be stored under carefully controlled temperatures, and, when potted, they are brought into flower in cooler months of the year. Temperature also controls the opening of the crocus flower. When near the critical temperature, the perianth (sepals and petals) opens with an increase of less than 1° F. Insects are the pollinators in the iris family, attracted by the showy flower parts. In some gladioli a coordination exists between certain moths and the shape of the flower. While hovering, the moth can reach to the base of the floral tube with its long tongue. Pollen already adhering to the body of the moth is left on the stigma, and fresh pollen sticks to the moth to be left in another flower. Do you know anything more about this topic that you’d like to share?
Pie Charts, also known as circle graphs, are ways of displaying the proportions, or percentages, of data that fall into different categories. It makes sense that these graphs are useful for displaying categorical data. To make a pie chart we start with a circle, and cut it into slices like a pizza. Yeah, it would probably make more sense if we went with a "pie" analogy, but where's the fun in being predictable? If half the data (50%) falls into one category, its corresponding slice will be half (50%) of the pizza. If one-eighth of the data falls into one category, its corresponding slice will be one-eighth of the pizza, and so on. Our advice is to not invite too much data to your house when you're throwing a party, so that you can keep most of the pizza for yourself. Thinking about backpacks helps us get to our happy place, so we'll do so once again. Suppose students had the following colors of backpacks: red, blue, red, red, red, blue, green, green. There are 8 backpacks total. Half the backpacks are red, one quarter are blue, and one quarter are green. We can represent this by the following circle graph: In this graph, we labeled each individual slice of the graph with the category it represented. We could instead have a key that explains what each color means. It may not be necessary in this example, but sometimes you will have super-duper thin slices, so it's a good idea to get some practice. If, on the other hand, one of your special skills is the ability to replicate classic works of art on the head of a pin, you may have no need for a key. If you're making pie charts and you don't have different colored writing utensils handy, instead of making the pizza slices different colors you can make the shading of each slightly different, like this: The important thing is to be able to tell the slices apart. If that means drawing a different Black Eyed Pea inside each one, so be it. Whatever works for you. Just make sure Fergie has the biggest slice. You know she'll get all "diva" about it.
World Day for Water Water is a basic requirement for all life, yet water resources are facing increasing demands from, and competition among, users. In 1992, the UN General Assembly designated 22 March of each year as the World Day for Water. The international observance of World Water Day is an initiative that grew out of the 1992 United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro. The United Nations General Assembly designated 22 March of each year as the World Day for Water by adopting a resolution. This world day for water was to be observed starting in 1993, in conformity with the recommendations of the United Nations Conference on Environment and Development contained in chapter 18 (Fresh Water Resources) of Agenda 21. States were invited to devote the Day to implement the UN recommendations and set up concrete activities as deemed appropriate in the national context. The Subcommittee welcomes the assistance offered by IRC International Water and Sanitation Centre to contribute to an information network centre in support of the observance of the Day by Governments, as required.
What is considered a picture book? A picture book combines visual and verbal narratives in a book format, most often aimed at young children. With the narrative told primarily through text, they are distinct from comics, which do so primarily through sequential images. What is the purpose of a picture book? Inspiring Visual Thinking – Illustrations in a picture book help children understand what they are reading, allowing new readers to analyze the story. If children are having difficulty with the words, the illustrations can help them figure out the narrative, which can increase their comprehension. What is the difference between a picture book and an illustrated book? In a picture book the drawings are there to relay the story, sometimes with no text whatsoever. Whereas the illustrated book’s drawings are there to assist in telling the story and to highlight certain parts of the narrative. How do I write a photo book? These are the 12 steps to writing a children’s book. - Find Your Best Idea. You probably have an idea already, but you should work on refining it. … - Develop Your Main Character. … - Write the Right Length. … - Start the Story Quickly. … - Figure Out the Main Problem. … - Use Repetition. … - Write for Illustrators. … - End the Story Quickly. Can a picture book have words? They are reliant on both text and illustration and text length can range from 100–1000 words, sometimes more. However, the best picture books are short on text and rely equally or heavily on illustration. What are the characteristics of picture books? - Words must be carefully selected. - Often a rhythmic style of writing. - Catch children’s attention and stimulate their interest while story is read aloud. - Often single words or phrases are repeated. - Words carefully selected to set mood and create vivid images. Why are picture books important for adults? The picture book, with its interaction between text and illustration, with its appeal that the reader analyze that interaction, helps develop visual intelligence. It helps us look for meaning in the visual. Why are wordless picture books important? Sharing wordless books is a terrific way to build important literacy skills, including listening skills, vocabulary, comprehension — and an increased awareness of how stories are “built,” as the storyteller often uses a beginning, middle, end format. What can children learn from picture books? Children learn the beginning, middle, and end of a story and can often relate to the age-appropriate issues and conflicts presented in a picture book. Picture books allow parents to spend time talking with their children about the story, pictures, and words. This interaction builds reading comprehension. Are all picture books 32 pages? Picture books are almost always 32 pages. The reasons for this are physical: when you fold paper, eight pages folds smoothly into what’s called a signature, while any more results in a group of pages too thick to bind nicely. Do Picture books have page numbers? Dear Notta Paige Counter: Picture books are typically 32 pages because books are produced in page-count multiples of eight. What is illustration in a book? An illustration is a decoration, interpretation or visual explanation of a text, concept or process, designed for integration in published media, such as posters, flyers, magazines, books, teaching materials, animations, video games and films. An illustration is typically created by an illustrator. What makes a great picture book? The best ones are a perfect symbiosis of words and pictures, each element supporting, furthering, or deepening the story in some way. For me, as a writer and a reader, the best picture books have several key elements: A unique story. How do you properly write a book? Decide what the book is about Write the argument of your book in a sentence, then stretch that out to a paragraph, and then to a one-page outline. After that, write a table of contents to help guide you as you write, then break each chapter into a few sections. Think of your book in terms of beginning, middle, and end.
WHAT IS 3D PRINTING? 3D printing is a manufacturing process that builds layers to create a three-dimensional solid object from a digital model. To print a 3D object, the manufacturer uses a 3D computer-aided design (CAD) program to create a digital model that gets sliced into very thin cross-sections called layers. During the print process, the 3-D printer starts at the bottom of the design and builds up successive layers of material until the object is finished. In the past, the cost of 3-D printing was expensive and the technology was only used by large corporations, but the development of desktop 3D printers has made the technology more accessible to small and mid-sized businesses and home users. Today, 3D printers are used to create anything from a new toy or motorcycle part to manufacturing prototypes for testing purposes. Before 3D printers existed, creating a prototype was time-consuming and expensive, requiring skilled craftsmen and specific machinery. Instead of sending modeling instructions to a production company, advances in 3-D printing have allowed businesses to insource prototype production on a regular basis. Michael Feygen is credited with developing the first 3D printer in 1985. 3D printing is known by many names; depending upon the context, the term may also be referred to as rapid prototyping, stereolighography, architectural modeling or additive manufacturing. Different 3-D printers use different materials to build layers. Some use liquid polymer or gel; others use resin, which tends to be more expensive.
Our solar system consists of two large classes of planets: rocky terrestrial planets like Earth or Mars and giant planets formed of gases like Neptune or Saturn. Thus, the other planets located outside our system, the exoplanets, have long been categorized in these two classes, until today. An international team led by an astronomer from the Université de Montréal (UdeM) has succeeded in drawing a clearer picture of what could be a third class of planets that are not found in our solar system. The latter, called sub-Neptunians or super-Terres, were known before, but nobody could identify them. The most amazing thing is that they represent no less than 80% of the planets in our galaxy! To get there, the team led by Björn Benneke, a professor of astronomy at UdeM, compiled many datasets from NASA’s Hubble and Spitzer space telescopes for five years. The team focused mainly on a planet named GJ 3470 b. It is 12.6 times more massive than the Earth, but less massive than Neptune (an intermediate between the rocky and gaseous planets of the solar system). Also, 80% of the planets that make up our galaxy are of a more or less similar mass and size. For a long time, scientists were aware of their size and shape, but nobody had been able to determine their chemical composition. Thanks to this discovery, we can now establish the majority of the planets of our universe. Mr. Benneke mentions that before, scientists looked at the wrong sample of planets (those of our solar system) and therefore could not conduct a complete analysis of the universe. The sub-Neptunian planets, or super-Earths, could even shelter life, as the astronomer of UdeM says: Now, scientists will continue to observe GJ 3470b in more detail with NASA’s James Webb Space Telescope to better understand these new planets and be able, who knows, to find a way of life on a similar sub-Neptunian. The study us published in Nature Astronomy.
Malayalam language is widely spoken in the south Indian state of Kerala. Literature optionals are becoming very popular among the aspirants. Malayalam is one such optional provided by upsc. The subject does not require you to be an expert in the language, rather a basic familiarity with the language and it’s systematic reading. One should be familiar with the language both spoken and written as both optional papers require you to write the exam in the language itself. The syllabus and booklist for the subject is very concise and brief to avoid any kind of misunderstanding. Paper 1 requires you a deep reading for the subject and it’s characteristics and origin whereas paper 2 of the optional requires you to study the various literary works of the authors and analyse the work. The syllabus and booklist of the subject is given below for an understanding. Early phase of Malayalam Language: 1.1 Various theories: origin from proto Dravidian, Tamil, Sanskrit. 1.2 Relation between Tamil and Malayalam: Six nayas of A.R. Rajarajavarma. 1.3 Pattu school-definition, Ramacharitam, later pattu works-Niranam works and Krishnagatha. Linguistic features of : 2.1 Manipravalam-definition. Language of early manipravala works-Champu, Sandesakavya, Chandrotsava, minor works. Later Manipravala works-medieval Champu and Attakkatha. 2.2 Folklore-Southern and Northern ballads, Mappila songs. 2.3 Early Malayalam prose-Bhashakautaliyam, Brahmandapuranam, Attaprakaram, Kramadipika and Nambiantamil. Standardization of Malayalam 3.1 Peculiarities of the language of Pana, Kilippattu, and Tullal. 3.2 Contributions of indigenous and European missionaries to Malayalam. 3.3 Characteristics of contemporary Malayalam: Malayalam as the administrative language. Language of scientific and technical literature-media language. Ancient and Medieval Literature: 4.1 Pattu-Ramacharitam, Niranam works and Krishnagatha. 4.2 Manipravalam-early and medieval manipravala works including attakkatha and champu. 4.3 Folk literature. 4.4 Kilippattu, Tullal, and Mahakavya. 5.1 Venmani poets and contemporaries. 5.2 The advent of Romanticism-Poetry of Kavitraya i.e., Asan, Ulloor and Vallathol 5.3 Poetry after Kavitraya. 5.4 Modernism in Malayalam poetry. 6.3 Short story 6.4 Biography, travelogue, essay and criticism. 1.1 Ramacharitam-Patalam 1. 1.2 Kannassaramayanam-Balakandam first 25 stanzas. 1.3 Unnunilisandesam-Purvabhagam 25 slokas including Prastavana 1.4 Mahabharatham Kilippattu-Bhishmaparvam., 2.1 Kumaran Asan-Chintavisthayaya Sita. 2.3 G. Sankara Kurup-Perunthachan. 2.4 N.V. Krishna Variar-Tivandiyile Pattu. 3.1 ONV -Bhumikkoru Charamagitam 3.2 Ayyappa Panicker-Kurukshetram. 3.3 Akkittam-Paudatha Messanthi 3.4 Attur Ravivarma-Megharupan. 4.1 O. Chanthu Menon-Indulekha 4.3 O V Vijayan-Khasakkinte Ithihasam. 5.1 MT Vasudevan Nair-Vanaprastham (Collection). 5.2 N S Madhavan-Higvitta (Collection). 5.3 C J. Thomas-1128-il Crime 27. 6.1 Kuttikrishna Marar-Bharataparyatanam 6.2 M. K Sanu-Nakshatrangalute snehabhajanam 6.3 V.T. Bhattathirippad-Kannirum Kinavum 1.All the novels, short stories, poems and biographies prescribed in the syllabus. Malayalam magazine such as Bhashaposhini which talks about contemporary issues in the Malayalam Literature world. 2.Kairaliyude Katha – M. Krishna Pillai Malayala Sahithya Charithram – 3.Kalaghattangalilude – Erumeli Civil Service exam Malayalam Optional paper I – Jobin S Kottaram 4.Civil Service exam Malayalam Optional paper II – Jobin S Kottaram, Renu Raj, Aswathy
Carbon dating worksheet So, if you were asked to find out carbon's half-life value (the time it takes to decrease to half of its original size), you'd solve for t number of years when in any remains will have broken down. So, objects older than that do not contain enough of the isotope to be dated. Once you find your worksheet, click on pop-out icon or print icon to worksheet to print or download. You can & download or print using the browser document reader options. Again, please keep their identity a secret Click on the "Continue" button search with your zip/postal code. Libby and others (University of Chicago) devised a method of estimating the age of organic material based on the decay rate of carbon-14. is the quantity of radioactive material at time zero, X is the amount remaining after time t, and k is the first order rate constant, which is a characteristic of the isotope undergoing decay. In this article, we will examine the methods by which scientists use radioactivity to determine the age of objects, most notably carbon-14 dating. Carbon-14 dating is a way of determining the age of certain archeological artifacts of a biological origin up to about 50,000 years old. Easily modified for different abilities, with my low ability I made all the percentages either 75%, 50% or 25% to make it much easier for them. The worksheets can be used in a number of ways, I used them in two ways, I laminated them both in the same pouch front to back for them to use as a mini whiteboard and write directly on them with a whiteboard pen then rub out the ink for reuse for different questions and classes and to use as group work.
Behavior Intervention and Positive Behavior Support (PBS) On this website, we use the term Positive Behavior Support (PBS) to describe the approach used to provide intensive individualized interventions to individual children with challenging behavior. We also refer to program-wide implementation of PBS (PW-PBS) or program-wide adoption of the Pyramid Model. PW-PBS is the expansion of this model to classrooms and programs. This section of the web site provides information and resources for the use of PBS in the design of effective interventions for individual children with persistent challenging behavior. What is PBS? PBS provides a process to understand and resolve the problem behavior of individuals or children that is based on values and empirical research. It offers an approach to develop an understanding of why the child engages in problem behavior and strategies to prevent the occurrence of problem behavior while teaching the child new skills. Positive behavior support offers a holistic approach that considers all factors that have an impact on a child and the child’s behavior. It can be used to address problem behaviors that range from aggression, tantrums, and property destruction to social withdrawal. The Origins of PBS In the early 1980’s, there were important advances in the design and application of interventions for challenging behavior. These advances were driven by research on innovations in approaches for behavior change and shifts in cultural values about the use of aversive and dehumanizing intervention practices with vulnerable populations. The non-aversive technology that emerged in the late 1980’s and early 1990s for addressing the challenging behaviors of individuals with severe disabilities was referred to as positive behavioral support (PBS). This approach included the use of functional assessment, antecedent manipulations, teaching strategies, and changes in reinforcement contingencies with a focus on achieving lifestyle changes as the outcome of intervention. Over the last three decades there have been significant advancements in PBS in its use with diverse populations and with both individuals and within programs and systems. Today, the term PBS is used to describe the implementation of a broad approach to provide the supports needed to achieve basic lifestyle goals while reducing the challenging behavior that might impede those goals. PBS can be applied with individuals, within schools and school districts (i.e., school-wide PBS) and within early childhood programs (i.e., program-wide PBS).
Igneous rocks are formed by the cooling and crystallization (solidification) of magma. Magma is a complex, highly variable mixture of molten rock, dissolved gas and solid crystals. We will briefly discuss each of these components. a. Molten rock. The earth's temperature increases with depth at a rate of about 2 degrees Centigrade every 100 meters. At great depths, high temperatures cause rock to melt. Liquid rock is less dense than solid rock, and so may rise towards the earth's surface, much like a hot air balloon will rise through the surrounding, cooler atmosphere. In most cases, rising magma will cool and solidify somewhere within the earth. In some cases, the magma will break through to the surface. b. Dissolved gasses. The molten rock beneath the earth is subjected to enormous pressure from the weight of overlying rock. This pressure forces various gases to dissolve within the liquid rock. A good analogy is a bottle of Coke. At the bottling plant CO2 gas under high pressure is forced into the liquid Coke. To keep the pressure high, and the gas dissolved in the liquid, a cap is put on the bottle. If you uncap the bottle this removes the pressure and the dissolved gas bubbles out of solution, giving Coke its fizz. The gas may escape directly into the atmosphere, or it may mix with some of the liquid to form a frothy, foamy head. If the gas escapes rapidly, like when the bottle is shaken before it is opened, the force of the escaping gas is so powerful that it blows some of the liquid right out of the bottle. Magma behaves similarly. When magma reaches the surface, it is "uncapped", that is, the pressure of the overlying rock is removed. As a result, the dissolved gas bubbles out of the liquid rock. If you could look down into an erupting volcano the magma would be fizzing and the bubbles would create a frothy "head" on the lava. If large amounts of gas escape all at once, some of the red-hot, liquid rock will be blown into the air. Most of the violence associated with volcanic eruptions is due to the force of escaping gas. c. Solid mineral crystals. Magma typically contains dozens of different elements, and so the potential to create hundred of different minerals. Each of these minerals crystallizes at a different temperature. As a magma slowly cools, high temperature minerals will form first, low temperature minerals last. For example, consider two minerals: "A" with a melting point of 1000 degrees, and "B" with a melting point of 750 degrees. If the magma is at 1250 degrees, both "A" and "B" will be liquid. If the magma is at 700, both "A" and "B" will be solid crystals. If the magma happens to be at 850 degrees, there will be solid crystals of "A" contained in liquid "B". Except under extreme conditions, magma will almost always contain some crystals of high temperature minerals. 2. Classification of igneous rocks. Once formed from the solidification of magma, the resulting igneous rocks are classified based on texture and on composition. Texture refers to the size of the individual crystals contained in a rock. The size of these crystals depends primarily on the rate at which magma cools and solidifies. In liquid magma, individual atoms are free to move around. As a body of magma cools, these individual atoms lose energy and come together to form solid mineral crystals. Crystal growth only occurs when liquids are present. Once all liquids solidify, crystal growth stops. The size of crystals produced depends on the rate at which the magma cools. If cooling is very slow, minerals have lots of time to grow, and so large crystals are produced. If cooling is rapid, little time is available for growth, and so crystals will be small. If cooling is extremely rapid, individual atoms will be frozen in place and crystals may not form at all. a. Igneous textures: phaneritic. Rate of cooling depends on where magma cools. Most bodies of magma rising to the surface get emplaced (stuck) inside the earth’s crust. Igneous rocks that solidify within the crust are called "intrusive rocks" or "plutonic rocks" (named for Pluto, the Roman God of the Underworld). Emplaced bodies of intrusive rock are called "plutons". Plutons are well-insulated by miles of overlying rock and so heat escapes very slowly. As a result, intrusive magmas cool very slowly, perhaps requiring tens of thousands of years, and crystals have the time to grow relatively large. Intrusive igneous rocks typically have crystals about the size of a match head. In general, intrusive rocks possess individual crystals that are visible to the naked eye. Rocks with crystals this size have a "phaneritic" texture. Look at your granite specimen. This is a phaneritic rock. You can easily see individual crystals of quartz (grayish-glassy), a pinkish feldspar, and biotite (black). The granite pegmatite has much larger crystals and a slightly different mineral composition. The feldspar here is a more whitish variety. b. Igneous textures: aphanitic Magma that reaches the earth's surface forms "extrusive rocks". These magmas are exposed to the atmosphere and so cool rapidly, usually solidifying within a few days. As a result, crystals have very little time to grow and so are relatively small. Extrusive rocks do contain crystals, but most are too small to be seen with the unaided eye. Rocks with crystals this size have an "aphanitic" texture. Aphanitic rocks often have a fine-grained, homogenous appearance, very similar to concrete. Look at the rhyolite. This rock is composed of the same minerals as granite. The only difference between the two is that the magma forming the rhyolite cooled rapidly on the surface, while the magma forming the granite cooled slowly, deep within the earth. Compare the gabbro specimen and the basalt. Both are formed from mafic magmas. Gabbro is a phaneritic intrusive rock, while basalt is an aphanitic extrusive rock. c. Igneous textures: glassy. Magma may cool almost instantaneously if it is extruded directly into water. When this occurs, the magma solidifies instantly and no crystals are formed at all. The resulting rock has little or no crystalline structure and has a glassy texture. Examine obsidian that is also called "volcanic glass". The magma producing was very similar in composition to that which formed the granite and the rhyolite, but was cooled so quickly that no crystals were formed. People make "glass" by imitating this natural process. Pure quartz sand is melted in a furnace to form a magma. Small quantities of this magma are removed from the furnace, shaped into pop bottles or whatever, and rapidly cooled by exposure to the air. Since the quartz has no time for quartz crystals to form, a clear "glass" is produced. Obsidian is discolored by small amounts of iron and other impurities. d. Igneous textures: porphyritic. Magmas contain all the different elements necessary to produce a huge variety of different minerals. Different minerals crystallize at different temperatures. As a magma begins cooling inside the earth, high-temperature minerals are the first to form crystals. These solid crystals float within the remaining molten rock. This partially crystallized / partially molten magma is then extruded, so that it cools very rapidly. The result is a rock texture called "porphyritic", where large "phenocrysts" (the big, high-temperature crystals) are encased within a matrix of low-temperature, aphanitic crystals, called the "groundmass". Examine the rhyolite porphyry. This rock exhibits two distinctive crystal-sizes. The large, light-colored crystals are potassium feldspar. These crystals were the first to form, at a relatively high-temperature. The feldspar phenocrysts are surrounded by a dark-gray groundmass of aphanitic crystals, formed when the magma was later cooled on the surface. The specimens of andesite have a few phenocrysts, so this might be considered andesite porphyry. Here, both the phenocrysts and the groundmass are composed of dark-colored, relatively mafic minerals. e. Igneous textures: vesicular Examine both the scoria and pumice that are rocks produced by gassy, violent, volcanic eruptions. The holes in these rocks, called "vesicles", were formed as gas bubbled out of the liquid magma. The crystallization of the magma preserved these holes. The basalt specimen in your collection has some vesicles, also, and was called a vesicular basalt. f. Igneous textures: pyroclastic. Extrusions of magma are often very violent events. Volcanic gas bubbling out of de-pressurized magma has enormous force and is capable of hurling both solid rock and molten lava great distances. Rocks formed from the material that has blown out of an erupting volcano possess a "pyroclastic" texture. Pyroclastic literally means "fiery chunks. Examine the welded tuff. Tuff is a rock formed from volcanic ash. Ash is a fine, dusty material produced when very violent eruptions pulverize rock and blow it into the atmosphere. This ash originally settled out in fluffy piles, but has since been welded (consolidated) into a rock. Magmas vary tremendously in composition, with the potential to form hundreds of different minerals. For our purposes, we will generalize all magmas into only three types. a. Felsic magma. Felsic magmas are high in silicon and low in iron. These magmas produce rocks that tend to be light in color and low in density, often producing rocks containing a lot of quartz. b. Mafic magma. Mafic magmas are high in iron, but are relatively low in silicon. These magmas produce rocks that are dark in color and high in density, containing little quartz. c. Intermediate magma. These magmas are between mafic and felsic in composition. The resulting rocks fall between felsic and mafic rocks in terms of their physical characteristics. Look at your rhyolite specimen. This felsic rock is called rhyolite, and it is composed primarily of silicon-rich minerals, particularly quartz. Rhyolite is relatively light in color and low in density. Contrast rhyolite to specimen basalt, a mafic rock. It contains less silicon and more iron, so it is dark in color and high in density. Compare rhyolite and basalt to andesite. Andesite is intermediate in composition, containing roughly equal amounts of mafic and felsic minerals, and so is grayish in color with a moderate density.
A hierarchical IP address or IPv4 contains various classes in its address. IPv4 is 32 bits binary numbers. IP address assignment on the network entirely depends on Internet Corporation for Assigned Names and Numbers (ICANN). Based on the requirement of hosts per network, Internet Protocol version 4 or IPv4 is broken into five classes and these classes can be easily identified by the first octet of IP address. - Class A - Class B - Class C - Class D - Class E Note: All these classes of IP addresses can be identified by the first octet of the address. How to find the Network and Host number in an IP address? You can use the below formula to find the total number of networks and Host per class in an IP address. - Number of Networks: 2Network bits - Number of Host per Network: 2Host bits-2 When calculating the number of hosts per network, two IPs are always subtracted from the total IPs because the first IP of a network is always reserved for the network number and the last IP is reserved for Broadcast IP. Refer above formula to find the number of Host per Network (2Host bits-2). Class A: IPv4 Address classes In Class “A” addresses: The first bit of the first octet is set to zero (0), and this first octet or first dotted-decimal represents the Network part of this address. The First octet ranges from 1-127 or 00000000-01111111. Excluding the first octet or first dotted-decimal part, the remaining will be the Host part of this address. Note: Class “A” IP address ranges between 1 to 126 only, because IP 127 is reserved for Loopback address. - Number of possible Networks in Class A = 28-1= 27 = 127 - Number of Hosts in class A (2Host bits-2) = 224-2= 16777214 - The default subnet mask for class A = 255.0.0.0 - IP format for class A = 0NNNNNNN.HHHHHHHH.HHHHHHHH.HHHHHHHH Class B: IPv4 Address classes In class “B” addresses: The first bit is set to 1 and the second bit set to 0, and the first 16 bits or the first two dotted-decimal represents the Network part of the address. Further, the remaining part would be the Host of the address. Note: Class “B” IP address ranges between 184.108.40.206 to 220.127.116.11 and 2 bits are reserved for Loopback address. - Hence, the Number of possible Networks in class B = 214=16384 - Number of Hosts per network in class B = 216-2-2 = 65534 - The default subnet mask for class B = 255.255.0.0 - IP format for class B = 10NNNNNN.NNNNNNNN.HHHHHHHH.HHHHHHHH Class C: IPv4 Address classes In class “C” addresses: The first two bits set to 1 and the third bit set to 0 which means the first 24 bits are the network part of the IP address and the remaining will be the Host. Note: Class “C” IP addresses range between 192.0.0.0 to 18.104.22.168 and 3 bits are reserved for Loopback address. - Hence, the Number of possible Networks in Class “C”= 224-3= 221= 2097152 - Number of Hosts per network in class C = 28-2 = 254 - The default subnet mask for class C = 255.255.255.0 - IP format for class C = 110NNNNN.NNNNNNNN.NNNNNNNN.HHHHHHHH Class D: IPv4 Address Classes Unlike Class A, B, and C, Class D addresses are not used for normal networking operations. Class D IP addresses are used for Multicasting applications. In Class D addresses; The first three bits are set to 1 and the fourth bit set to 0. All 32 bits are reserved for the Network part and used for multicasting applications. Note: Class D IP addresses ranges between 22.214.171.124 to 126.96.36.199. It is reserved for Multicasting data hence; it doesn’t require any Host in their addressing. Further, Class D addresses don’t have any subnet mask. Class E: IPv4 Address classes The uses of Class E addresses are reserved for Study or Research and Development purposes. In this class, the first four network bits are set to 1 hence; it ranges between 240.0.0.0 to 255.255.255.255. Similar to the Class D address, Class E also doesn’t have any subnet mask. Bit-wise representation in IP address classes Class A: (0.0.0.0 – 127.255.255.255) - 0. 0. 0 = 00000000.00000000.00000000.00000000 - 127.255.255.255 = 01111111.11111111.11111111.11111111 Class B: (128. 0. 0. 0 – 188.8.131.52) - 128. 0. 0. 0 = 10000000.00000000.00000000.00000000 - 184.108.40.206 = 10111111.11111111.11111111.11111111 Class C: (192. 0. 0. 0 – 220.127.116.11) - 192. 0. 0. 0 = 11000000.00000000.00000000.00000000 - 18.104.22.168 = 11011111.11111111.11111111.11111111 Class D: (224. 0. 0. 0 – 22.214.171.124) - 224. 0. 0. 0 = 11100000.00000000.00000000.00000000 - 126.96.36.199 = 11101111.11111111.11111111.11111111 Class E: (240. 0. 0. 0 – 255.255.255.255) - 240. 0. 0. 0 = 11110000.00000000.00000000.00000000 - 255.255.255.255 = 11111111.11111111.11111111.11111111 IP Address classes: Chart Representation \|Address Classes\|\|Range\|\|Bit Pattern of 1st byte\|\|Decimal Range\|\|Default Subnet Mask\|\|Reserved for\| \|A\|\|188.8.131.52 to 184.108.40.206\|\|0xxxxxxx\|\|1 to 127\|\|255.0.0.0\|\|Governments\| \|B\|\|220.127.116.11 to 18.104.22.168\|\|10xxxxxx\|\|128-191\|\|255.255.0.0\|\|Medium Companies\| \|C\|\|192.0.0.0 to 22.214.171.124\|\|110xxxxx\|\|192-223\|\|255.255.255.0\|\|Small Companies\| \|D\|\|126.96.36.199 to 188.8.131.52\|\|1110xxxx\|\|224-239\|\|Not Applicable\|\|Reserved for Multicasting\| \|E\|\|240.0.0.0 to 255.255.255.255\|\|11110xxx\|\|240-255\|\|Not Applicable\|\|Experimental or future use\|
Deflection Plate Assembly Electron beam, after leaving the electron gun, passes through the two pairs of deflection plates called the deflection plate assembly . One pair of deflection plates is mounted vertically and deflects the beam in horizontal or X-direction and so called the horizontal or X-plates and the other pair is mounted horizontally and deflects the beam in vertical or Y-direction and called the vertical or Y-plates. These plates are to deflect the beam according to the voltage applied across them. For example id a constant pd is applies to the set of Y-pates, the electron beam will be deflected upward if the upper plate is +ve. In case the lower plate is +ve then the beam will be deflected downward. Similarly, if a constant pd is applied to the set of X-plates , the electron beam will be deflected to the left or to the right of the tube axis according to the condition whether the left or right plate is +ve. When a sinusoidal voltage is applied to Y-plates, the beam will be moved up and down according to the variation of plate potential. If the frequency of variation is more than 16Hz the deflection will be a vertical line in the centre of the screen. In case the sinusoidal voltage is applied to X-plates and frequency of variation is more than 16Hz the deflection will be a horizontal line. If potentials are applied to both sets of plates simultaneously, the deflection will be an oblique line. The amount of deflection is in proportion to the voltage applied to the pair of plates.
From October 28, 2006 This Thursday Al Uy from Syracuse University came to talk to the Ecology, Evolution and Behaviour group at Queen’s. Al spoke about his research on the ecology and evolution of visual signaling in birds. Plumage colour in birds is known to be involved in conspecific communication, including the signaling of quality to potential mates. In many species, females can gain information about the condition or health of a certain male just by assessing the colour of his feathers. Sexual selection for honest signaling is often implicated in the evolution of brightly coloured plumage, much like the evolution of the peacock’s tail described in my last post. Al Uy is interested in understanding how sexual selection might contribute to the speciation process, since changes in sexual signals can lead to reproductive isolation between two populations. He pointed out that this idea originated with Darwin, who noticed that often the only difference between closely related species is a sexually dimorphic trait such as male plumage colour. To understand why this might be, Al studies the plumage colour of small birds called the bearded manakins with an interesting mating system: the males gather at display sites called leks, where they clear an area of the forest floor and dance to attract females. There are several subspecies of bearded manakins, all with striking differences in male colouration (whereas the females are all plain and look alike). Here are two of the manakin subspecies Al works on (golden-collared and white-bearded males): The signal function of manakin beards Al began his talk by discussing his investigation of the signal function of colour in the golden-collared manakin, which formed the groundwork for his research in signal diversification. Al and his students have found that the yellow colour of the male ‘beard’ plumage functions as a signal of male quality that females assess during male dancing displays, since males with brighter yellow beards tend to be larger, have higher display rates, and obtain more matings than their dull-bearded counterparts. Al also tested whether the brightness of the male plumage translated into conspicuousness from the point of view of the female manakins. He used a model that took account of avian perception, ambient light during male display, the reflectance of male plumage and the reflectance of the visual background during display (the dancing court). Consistent with the predictions of sexual selection theory, male conspicuousness as calculated by this model was related to male mating success. In other words, more conspicuous males obtained more matings. Unexpectedly, Al found that the darkness of the visual background was actually more important in explaining the variation in mating success than plumage reflectance, suggesting an important role of the visual habitat in shaping conspicuousness and the evolution of lekking. Al thinks that the lek mating system might have arisen from males becoming more competitive for the specific areas of the forest providing the best visual background for display. In the near future Al plans to test this idea by comparing the reflectance properties of the lek habitat with other areas in the forest. Why are there so many beard colours? The next part of Al’s talk focused on his main research interest: understanding what factors might promote the diversification of sexual signals like manakin beard colour. The basic hypothesis he is testing is that changes in the visual habitat can drive the diversification of visual signals. In order for plumage colour to be conspicuous (and therefore most effective as a signal) it needs to match the available light, contrast the background, and be tuned to the receptivity of the target individuals (females). Changes in any of these factors could have promoted the evolution of the four different male colour types found in the bearded manakins. Al plans to test this hypothesis in several ways. First, he will examine whether or not the evolution of retinal physiology might be driving the diversification of male colour. He plans test this idea by comparing the abundance of retinal cones between the different manakin subspecies. If females from different subspecies have retinas that are optimally sensitive to the beard colours of their mates, then changes in female perception might be driving changes in male beard colour. Al is also testing his ideas about colour diversification by studying a hybrid zone of golden-collared and white-bearded manakin populations. This is an area of Costa Rica where a river divides populations of the two manakin subspecies, although the yellow plumage trait (found in golden-collared manakins) extends slightly into the white-beaded population. One hypothesis Al is currently testing is whether this trait introgression has occurred because yellow plumage is intrinsically more attractive to the manakin females, although at this point he can only speculate as to why this might be. Al is testing this possibility by examining mate choice in the area where both yellow and white males are competing for the same mates. The other question Al would like to answer is: what stops yellow males from sweeping further into the white population? It seems unlikely that the river is a physical barrier isolating these populations since birds are certainly capable of crossing it. Instead, Al is looking into the possibility that a change in the visual habitat on either side of the river is maintaining the separation between these two populations. In other words, white birds in succeed in their habitat (despite some introgression of yellow males) because white is the most conspicuous and best colour for displaying in that habitat. Although Al’s talk was a bit long, it was enjoyed by the audience at Queen’s for telling a complete story without being overly technical, and some went so far as to claim it was the “best talk ever” (Dev Aiama). You can read more about Al Uy’s research here.
see the link for the website Thanks to the HR Educational team! Thank you everyone who voted for us! Finalists in our category! are reinforcing events gained from the pleasure of simply engaging in the behaviour. Studying may be intrinsically reinforcing if it gives a person the pleasure of increased understanding. A major goal of Heather Ronngard Educational Consultancy is to teach you how to involve your students in constructive behaviours, which will hopefully become intrinsically reinforcing. are objects, events or experiences which when they are presented immediately following the performance of a behaviour, strengthen the chances that the behaviour will occur again. A positive reinforcer may be anything that your student values, a desired object, an enjoyable activity or a person whom he/she likes. There are several types of reinforcers. are reinforcers such as money, points, stars or tokens which have value in that they can be traded for a preferred object, activity or experience are tangible objects such as candy, nuts, storybooks, puzzles, pencils with names and other items which are valued in and of themselves. are preferred activities valued because they are fun, exciting or because they generate a good feeling. Running errands, helping other children, free time in the library, working a puzzle and other classroom activities are just a few of the many available activity reinforcers. are positive consequences such as praise or non-verbal demonstrations of affection, which are valued because they are given by people important to the child. In praising the child it is important to praise the behaviour not the child. It is better and more powerful to say ‘I like the job you did cleaning up your desk’ than simply say ‘Good girl.’ Early Primary maths is important especially counting! The developmental counting stages are: 1 Positive reinforcement encourages cooperation and builds positive self- esteem 2 Give good example teach how to express feelings 3 Explain consequences for positive & negative behaviour 4 Spend time with child help with open ended questions 5 Communicate expectations clearly check also Join the Heather Ronngard school on Facebook
A chemist's view of the world is not as narrow as one might think! Yes, we start with the atom, and then go on to the rules governing the kinds of structural units that can be made from them. We are taught early on to predict the properties of bulk matter from these geometric arrangements. And then we come to H2O, and are shocked to find that many of these predictions are way off, and that water (and by implication, life itself) should not even exist on our planet! But we soon learn that this tiny combination of three nuclei and eight electrons possesses special properties that make it unique among the more than 15 million chemical species we presently know. When we stop to ponder the consequences of this, chemistry moves from being an arcane science to a voyage of wonder and pleasure as we learn to relate the microscopic world of the atom to the greater world in which we all live. The molecule of water A molecule is an aggregation of atomic nuclei and electrons that is sufficiently stable to possess observable properties — and there are few molecules that are more stable and difficult to decompose than H2O. In water, each hydrogen nucleus is bound to the central oxygen atom by a pair of electrons that are shared between them; chemists call this shared electron pair a covalent chemical bond. In H2O, only two of the six outer-shell electrons of oxygen are used for this purpose, leaving four electrons which are organized into two non-bonding pairs. The four electron pairs surrounding the oxygen tend to arrange themselves as far from each other as possible in order to minimize repulsions between these clouds of negative charge. This would ordinarily result in a tetrahedral geometry in which the angle between electron pairs (and therefore the H-O-H bond angle) is 109.5°. However, because the two non-bonding pairs remain closer to the oxygen atom, these exert a stronger repulsion against the two covalent bonding pairs, effectively pushing the two hydrogen atoms closer together. The result is a distorted tetrahedral arrangement in which the H—O—H angle is 104.5°. Although the water molecule carries no net electric charge, its eight electrons are not distributed uniformly; there is slightly more negative charge (purple) at the oxygen end of the molecule, and a compensating positive charge (green) at the hydrogen end. The resulting polarity is largely responsible for water's unique properties. Because molecules are smaller than light waves, they cannot be observed directly, and must be "visualized" by alternative means. This computer-generated image comes from calculations that model the electron distribution in the H2O molecule. The outer envelope shows the effective "surface" of the molecule as defined by the extent of the cloud of negative electric charge created by the eight electrons. The H2O molecule is electrically neutral, but the positive and negative charges are not distributed uniformly. This is illustrated by the gradation in color in the schematic diagram here. The electronic (negative) charge is concentrated at the oxygen end of the molecule, owing partly to the nonbonding electrons (solid blue circles), and to oxygen's high nuclear charge which exerts stronger attractions on the electrons. This charge displacement constitutes an electric dipole, represented by the arrow at the bottom; you can think of this dipole as the electrical "image" of a water molecule. As we all learned in school, opposite charges attract, so the partially-positive hydrogen atom on one water molecule is electrostatically attracted to the partially-negative oxygen on a neighboring molecule. This process is called (somewhat misleadingly) hydrogen bonding. Notice that the hydrogen bond (shown by the dashed green line) is somewhat longer than the covalent O—H bond. This means that it is considerably weaker; it is so weak, in fact,that a given hydrogen bond cannot survive for more than a tiny fraction of a second. Figure: Hydrogen bond between two water molecules The anomalous properties of water Water has long been known to exhibit many physical properties that distinguish it from other small molecules of comparable mass. Chemists refer to these as the "anomalous" properties of water, but they are by no means mysterious; all are entirely predictable consequences of the way the size and nuclear charge of the oxygen atom conspire to distort the electronic charge clouds of the atoms of other elements when these are chemically bonded to the oxygen. Water is one of the few known substances whose solid form is less dense than the liquid. The plot at the right shows how the volume of water varies with the temperature; the large increase (about 9%) on freezing shows why ice floats on water and why pipes burst when they freeze. The expansion between –4° and 0° is due to the formation of larger hydrogen-bonded aggregates. Above 4°, thermal expansion sets in as vibrations of the O—H bonds becomes more vigorous, tending to shove the molecules farther apart. The other widely-cited anomalous property of water is its high boiling point. As this graph shows, a molecule as light as H2O "should" boil at around –90°C; that is, it would exist in the world as a gas rather than a liquid if H-bonding were not present. Notice that H-bonding is also observed with fluorine and nitrogen. Surface tension and wetting Have you ever watched an insect walk across the surface of a pond? The water strider takes advantage of the fact that the water surface acts like an elastic film that resists deformation when a small weight is placed on it. (If you are careful, you can also "float" a small paper clip or steel staple on the surface of water in a cup.) This is all due to the surface tension of the water. A molecule within the bulk of a liquid experiences attractions to neighboring molecules in all directions, but since these average out to zero, there is no net force on the molecule. For a molecule that finds itself at the surface, the situation is quite different; it experiences forces only sideways and downward, and this is what creates the stretched-membrane effect. The distinction between molecules located at the surface and those deep inside is especially prominent in H2O, owing to the strong hydrogen-bonding forces. The difference between the forces experienced by a molecule at the surface and one in the bulk liquid gives rise to the liquid's surface tension. This drawing highlights two H2O molecules, one at the surface, and the other in the bulk of the liquid. The surface molecule is attracted to its neighbors below and to either side, but there are no attractions pointing in the 180° solid angle angle above the surface. As a consequence, a molecule at the surface will tend to be drawn into the bulk of the liquid. But since there must always be some surface, the overall effect is to minimize the surface area of a liquid. The geometric shape that has the smallest ratio of surface area to volume is the sphere, so very small quantities of liquids tend to form spherical drops. As the drops get bigger, their weight deforms them into the typical tear shape. Take a plastic mixing bowl from your kitchen, and splash some water around in it. You will probably observe that the water does not cover the inside surface uniformly, but remains dispersed into drops. The same effect is seen on a dirty windshield; turning on the wipers simply breaks hundreds of drops into thousands. By contrast, water poured over a clean glass surface will wet it, leaving a uniform film. When a liquid is in contact with a solid surface, its behavior depends on the relative magnitudes of the surface tension forces and the attractive forces between the molecules of the liquid and of those comprising the surface. If an H2O molecule is more strongly attracted to its own kind, then surface tension will dominate, increasing the curvature of the interface. This is what happens at the interface between water and a hydrophobic surface such as a plastic mixing bowl or a windshield coated with oily material. A clean glass surface, by contrast, has -OH groups sticking out of it which readily attach to water molecules through hydrogen bonding; this causes the water to spread out evenly over the surface, or to wet it. A liquid will wet a surface if the angle at which it makes contact with the surface is more than 90°. The value of this contact angle can be predicted from the properties of the liquid and solid separately. If we want water to wet a surface that is not ordinarily wettable, we add a detergent to the water to reduce its surface tension. A detergent is a special kind of molecule in which one end is attracted to H2O molecules but the other end is not, so these ends stick out above the surface and repel each other, cancelling out the surface tension forces due to the water molecules alone. Water the liquid The nature of liquid water and how the H2O molecules within it are organized and interact are questions that have attracted the interest of chemists for many years. There is probably no liquid that has received more intensive study, and there is now a huge literature on this subject. The following facts are well established: - H2O molecules attract each other through the special type of dipole-dipole interaction known as hydrogen bonding - a hydrogen-bonded cluster in which four H2Os are located at the corners of an imaginary tetrahedron is an especially favorable (low-potential energy) configuration, but... - the molecules undergo rapid thermal motions on a time scale of picoseconds (10–12 second), so the lifetime of any specific clustered configuration will be fleetingly brief. A variety of techniques including infrared absorption, neutron scattering, and nuclear magnetic resonance have been used to probe the microscopic structure of water. The information garnered from these experiments and from theoretical calculations has led to the development of around twenty "models" that attempt to explain the structure and behavior of water. More recently, computer simulations of various kinds have been employed to explore how well these models are able to predict the observed physical properties of water. This work has led to a gradual refinement of our views about the structure of liquid water, but it has not produced any definitive answer. There are several reasons for this, but the principal one is that the very concept of "structure" (and of water "clusters") depends on both the time frame and volume under consideration. Thus questions of the following kinds are still open: - How do you distinguish the members of a "cluster" from adjacent molecules that are not in that cluster? - Since individual hydrogen bonds are continually breaking and re-forming on a picosecond time scale, do water clusters have any meaningful existence over longer periods of time? In other words, clusters are transient, whereas "structure" implies a molecular arrangement that is more enduring. Can we then legitimately use the term "clusters" in describing the structure of water? - The possible locations of neighboring molecules around a given H2O are limited by energetic and geometric considerations, thus giving rise to a certain amount of "structure" within any small volume element. It is not clear, however, to what extent these structures interact as the size of the volume element is enlarged. And as mentioned above, to what extent are these structures maintained for periods longer than a few picoseconds? The view first developed in the 1950's that water is a collection of "flickering clusters" of varying sizes (right) has gradually been abandoned as being unable to account for many of the observed properties of the liquid. Current views of water structure The present thinking, influenced greatly by molecular modeling simulations beginning in the 1980s, is that on a very short time scale (less than a picosecond), water is more like a "gel" consisting of a single, huge hydrogen-bonded cluster. On a 10-12-10-9 sec time scale, rotations and other thermal motions cause individual hydrogen bonds to break and re-form in new configurations, inducing ever-changing local discontinuities whose extent and influence depends on the temperature and pressure. Recent work from Richard SayKally's lab shows that the hydrogen bonds in liquid water break and re-form so rapidly (often in distorted configurations) that the liquid can be regarded as a continuous network of hydrogen-bonded molecules. This computer-generated nanoscale view of liquid water is from the lab of Gene Stanley of Boston University. The oxygen atoms are red, the hydrogen atoms white Local structures and water clusters It is quite likely that over very small volumes, localized (H2O)n polymeric clusters may have a fleeting existence, and many theoretical calculations have been made showing that some combinations are more stable than others. While this might prolong their lifetimes, it does not appear that they remain intact long enough to detect as directly observable entities in ordinary bulk water at normal pressures. Theoretical models suggest that the average cluster may encompass as many as 90 H2O molecules at 0°C, so that very cold water can be thought of as a collection of ever-changing ice-like structures. At 70° C, the average cluster size is probably no greater than about 25. It must be emphasized that no stable clustered unit or arrangement has ever been isolated or identified in pure bulk liquid water. A 2006 report suggests that a simple tetrahedral arrangement is the only long-range structure that persists at time scales of a picosecond or beyond. And a 2007 study suggests that infrared radiation can stabilize clathrate-like clusters for up to several hours. Water clusters are of considerable interest as models for the study of water and water surfaces, and many articles on them are published every year. Some notable work reported in 2004 extended our view of water to the femtosecond time scale. The principal finding was that 80 percent of the water molecules are bound in chain-like fashion to only two other molecules at room temperature, thus supporting the prevailing view of a dynamically-changing, disordered water structure. Liquid and solid water Ice, like all solids, has a well-defined structure; each water molecule is surrounded by four neighboring H2Os. two of these are hydrogen-bonded to the oxygen atom on the central H2O molecule, and each of the two hydrogen atoms is similarly bonded to another neighboring H2O. The hydrogen bonds are represented by the dashed lines in this 2-dimensional schematic diagram. In reality, the four bonds from each O atom point toward the four corners of a tetrahedron centered on the O atom. This basic assembly repeats itself in three dimensions to build the ice crystal. When ice melts to form liquid water, the uniform three-dimensional tetrahedral organization of the solid breaks down as thermal motions disrupt, distort, and occasionally break hydrogen bonds. The methods used to determine the positions of molecules in a solid do not work with liquids, so there is no unambiguous way of determining the detailed structure of water. The illustration here is probably typical of the arrangement of neighbors around any particular H2O molecule, but very little is known about the extent to which an arrangement like this gets propagated to more distant molecules. Here are three-dimensional views of a typical local structure of water (left) and ice (right.) Notice the greater openness of the ice structure which is necessary to ensure the strongest degree of hydrogen bonding in a uniform, extended crystal lattice. The more crowded and jumbled arrangement in liquid water can be sustained only by the greater amount thermal energy available above the freezing point. The stable arrangement of hydrogen-bonded water molecules in ice gives rise to the beautiful hexagonal symmetry that reveals itself in every snowflake. Why is ice slippery? At temperatures as low as 200K, the surface of ice is highly disordered and water-like. As the temperature approaches the freezing point, this region of disorder extends farther down from the surface and acts as a lubricant. The illustration is taken from from an article in the April 7, 2008 issue of C&EN honoring the physical chemist Gabor Somorjai who pioneered modern methods of studying surfaces. To a chemist, the term "pure" has meaning only in the context of a particular application or process. The distilled or de-ionized water we use in the laboratory contains dissolved atmospheric gases and occasionally some silica, but their small amounts and relative inertness make these impurities insignificant for most purposes. When water of the highest obtainable purity is required for certain types of exacting measurements, it is commonly filtered, de-ionized, and triple-vacuum distilled. But even this "chemically pure" water is a mixture of isotopic species: there are two stable isotopes of both hydrogen (H1 and H2, the latter often denoted by D) and oxygen (O16 and O18) which give rise to combinations such as H2O18, HDO16, etc., all of which are readily identifiable in the infrared spectra of water vapor. And to top this off, the two hydrogen atoms in water contain protons whose magnetic moments can be parallel or antiparallel, giving rise to ortho- and para-water, respectively. The two forms are normally present in a o/p ratio of 3:1. The amount of the rare isotopes of oxygen and hydrogen in water varies enough from place to place that it is now possible to determine the age and source of a particular water sample with some precision. These differences are reflected in the H and O isotopic profiles of organisms. Thus the isotopic analysis of human hair can be a useful tool for crime investigations and anthropology research. It has recently been found (Langmuir 2003, 19, 6851-6856) that freshly distilled water takes a surprisingly long time to equilibrate with the atmosphere, that it undergoes large fluctuations in pH and redox potential, and that these effects are greater when the water is exposed to a magnetic field. The reasons for this behavior are not clear, but one possibility is that dissolved O2 molecules, which are paramagnetic, might be involved. Our ordinary drinking water, by contrast, is never chemically pure, especially if it has been in contact with sediments. Groundwaters (from springs or wells) always contain ions of calcium and magnesium, and often iron and manganese as well; the positive charges of these ions are balanced by the negative ions carbonate/bicarbonate, and occasionally some chloride and sulfate. Groundwaters in some regions contain unacceptably high concentrations of naturally-occuring toxic elements such as selenium and arsenic. One might think that rain or snow would be exempt from contamination, but when water vapor condenses out of the atmosphere it always does so on a particle of dust which releases substances into the water, and even the purest air contains carbon dioxide which dissolves to form carbonic acid. Except in highly polluted atmospheres, the impurities picked up by snow and rain are too minute to be of concern. Various governments have established upper limits on the amounts of contaminants allowable in drinking water; the best known of these are the U.S. EPA Drinking Water Standards. What kind of water is most healthy to drink? I am not aware of any evidence indicating that any one type of water (including highly "pure" water) is more beneficial to health than any other, as long as the water is pathogen-free and meets accepted standards such as those mentioned above. For those who are sensitive to residual chlorine or still have concerns, a good activated-carbon filter is usually satisfactory. More extreme measures such as reverse-osmosis or distillation are only justified in demonstrably extreme situations. "Pure" rainwater always contains some dissolved carbon dioxide which makes it slightly acidic. When this water comes into contact with sediments, it tends to dissolve them, and in the process becomes alkaline. The pH of drinking water can vary from around 5 to 9, and it has no effect on one's health. The idea that alkaline water is better to drink than acidic water is widely promoted by alternative-health hucksters who market worthless "water ionizer" machines for this purpose. Acidic water is sometimes described by engineers as "aggressive"; this refers to its tendency to corrode metal distribution pipes, but in this sense it is no more active than the hydrochloric acid already present in your gastric fluid! One occasionally hears that mineral-free water, and especially distilled water, are unhealthy because they "leach out" required minerals from the body. There is no truth to this; the fact is that mineral ions do not pass through cell walls by ordinary osmotic diffusion, but rather are actively transported by metabolic processes. An extensive 2008 study failed to confirm earlier reports that low calcium/magnesium in drinking water correlates with cardiovascular disease. Any well-balanced diet should supply all the mineral substances we need. It is well known that people who are engaged in heavy physical activity or are in a very hot environment should avoid drinking large quantities of even ordinary water. In order to prevent serious electrolyte imbalance problems, it is necessary to make up for the salts lost through perspiration. This can be accomplished by ingestion of salted foods or beverages (including "sports beverages"), or salt tablets. Water in our bodies About two-thirds of the weight of an adult human consists of water. About two-thirds of this water is located within cells, while the remaining third consists of extracellular water, mostly in the blood plasma and in the interstitial fluid that bathes the cells. This water, amounting to about five percent of body weight (about 5 L in the adult), serves as a supporting fluid for the blood cells and acts as a means of transporting chemicals between cells and the external environment. It is basically a 0.15M solution of salt (NaCl) containing smaller amounts of other electrolytes, the most important of which are bicarbonate (HCO3–) and protein anions. The water content of our bodies is tightly controlled in respect to both total volume and its content of dissolved substances, particulary ions. Drinking constitutes only one source of our water; many foods, especially those containing cells (fruits, vegetables, meats) are an important secondary source. In addition, a considerable amount of water (350-400 mL/day) is produced metabolically — that is, from the oxidation of glucose derived from foods. The quantity of water exchanged within various parts of our bodies is surprisingly large. The kidneys process about 180 L/day, returning most of the water to the blood stream. Lymph flow amounts to 1-2.5 L/day, and turnover of fluids in the bowel to 8-9 L/day. These figures are dwarfed by the 80,000 L/day of water that diffuses in both directions through capillary walls. How much water should I drink? The idea that everyone should drink "eight glasses" of water a day is one of those urban legends that never seems to go away; it is nicely debunked at this medical myths site. The body's daily water loss - Loss through breath: 800 mL - Minimal sweat loss: 100 mL - Fecal loss: 200 mL - Minimal urine loss: 500 mL Total: 1600 mL Ultimately, total water intake plus metabolic production must balance water loss. For a healthy unstressed adult, the figures shown here are typical minimum values. Notice that the major loss is through simple breathing. The minimal urinary loss is determined by the need to remove salts and other solutes taken in with foods or produced by metabolic processes. Individuals (such as many elderly) having reduced kidney function produce more dilute urine, and must therefore take in more water. And of course stress factors such as strenuous exercise, exposure to very high temperatures, or diarrhea can greatly increase the need for water intake. Consumption of overly large quantities of water can lead to electrolyte imbalance resulting in water intoxication. Children, with their low body masses, are especially susceptible. As we explained above, bulk liquid water consists of a seething mass of various-sized chain-like groups and that flicker in and out of existence on a time scale of picoseconds. But in the vicinity of a solid surface or of another molecule or ion that possesses an unbalanced electric charge, water molecules can become oriented and sometimes even bound into relatively stable structures. Water in ionic hydration shells Water molecules interact strongly with ions, which are electrically-charged atoms or molecules. Dissolution of ordinary salt (NaCl) in water yields a solution containing the ions Na+ and Cl –. Owing to its high polarity, the H2O molecules closest to the dissolved ion are strongly attached to it, forming what is known as the inner or primary hydration shell. Positively-charged ions such as Na+ attract the negative (oxygen) ends of the H2O molecules, as shown in the diagram below. The ordered structure within the primary shell creates, through hydrogen-bonding, a region in which the surrounding waters are also somewhat ordered; this is the outer hydration shell, or cybotactic region. Some recent experiments have revealed a degree of covalent bonding between the d-orbitals of transition metal ions and the oxygen atoms of water molecules in the inner hydration shell. In 2003, some chemists in India found (Inorg. Chem. 44(4) pp 816 - 818) that a suitable molecular backbone (above) can cause water molecules to form a "thread" that can snake its way though the more open space of the larger molecules. What all of these examples show is that water can have highly organized local structures when it interacts with molecules capable of imposing these structures on the water. Biowater: Bound water in biological systems It has long been known that the intracellular water very close to any membrane or organelle (sometimes called vicinal water) is organized very differently from bulk water, and that this structured water plays a significant role in governing the shape (and thus biological activity) of large folded biopolymers. It is important to bear in mind, however, that the structure of the water in these regions is imposed solely by the geometry of the surrounding hydrogen bonding sites. Water can hydrogen-bond not only to itself, but also to any other molecules that have -OH or -NH2 units hanging off of them. This includes simple molecules such as alcohols, surfaces such as glass, and macromolecules such as proteins. The biological activity of proteins (of which enzymes are an important subset) is critically dependent not only on their composition but also on the way these huge molecules are folded; this folding involves hydrogen-bonded interactions with water, and also between different parts of the molecule itself. Anything that disrupts these intramolecular hydrogen bonds will denature the protein and destroy its biological activity. This is essentially what happens when you boil an egg; the bonds that hold the eggwhite protein in its compact folded arrangement break apart so that the molecules unfold into a tangled, insoluble mass which, like Humpty Dumpty, cannot be restored to their original forms. Note that hydrogen-bonding need not always involve water; thus the two parts of the DNA double helix are held together by H—N—H hydrogen bonds. This image, taken from the work of William Royer Jr. of the U. Mass. Medical School, shows the water structure (small green circles) that exists in the space between the two halves of a kind of dimeric hemoglobin. The thin dotted lines represent hydrogen bonds. Owing to the geometry of the hydrogen-bonding sites on the heme protein backbones, the H2O molecules within this region are highly ordered; the local water structure is stabilized by these hydrogen bonds, and the resulting water cluster in turn stabilizes this particular geometric form of the hemoglobin dimer. Can you run your car on water? Not really. For water to act as a fuel, there must be some combination of oxygen and hydrogen that is energetically more stable than H2O, and no such molecule is known. This fact has failed to put to rest the venerable urban legend that some obscure inventor discovered a process to do this, but the invention was secretly bought up by the oil companies in order to preserve their monopoly. However, adding water to the fuel-air mixture in an internal combustion engine, a process known as water injection, has been employed for many years as a method of improving the performance of both piston- and turbine engines. Water injection kits are widely available, many offered by hucksters whose marketing falsely implies that their products allow you to "run your car on water". Don't believe it! And get some solid advice before you try this on a modern computer-controlled high compression engine. In 2007, a widely-cited YouTube video appeared that showed a sample of salt water "burning". This occurs only in the presence of a strong radio-frequency field, which supposedly dissociates the water into H2 and O2. These two gases then recombine, producing the flame. Although there has been much uninformed hype about this being some kind of a breakthrough as a source of "energy from water", there is no reason to believe that the First Law of Thermodynamics has been repealed. If the energy supplied by the radio-frequency source is taken into account, you can be sure that there has been no net energy gain. The actual mechanism of the process remains unclear. The fact that salt or some other ionic solute is required suggests that ions at the water's surface might be accelerated in the local field produced by the plasma discharge, helping to break up the molecules in the water vapor. Contributors and Attributions - Thumbnail: https://pixabay.com/photos/water-dro...h-wet-1759703/
Compare the Cookies Students will compare three different types of sugar cookies: class-made from scratch, ready-made dough for cookies, and boxed cookies. - Show the class the three different types of cookies (or ingredients) and ask your class which cookies (out of the three) will taste the best. What is their reasoning? - Have students help bake the ready-made dough cookies. You can cut them into Valentine shapes and decorate. - Have students make the from-scratch cookies using the ingredients provided. These can also be molded or cut into shapes. - When all of the cookies have been prepared, lay out each set separately and have students taste them. - After the taste-test, graph the opinions for each type of cookie and discuss why the home-made (should!) taste the best.
The British admiral Richard Howe, Earl Howe (1726-1799), commanded England's naval forces during the early years of the American Revolution and won the "First of June" victory over the French in 1794. Richard Howe was born on March 8, 1726, in London. He entered the British navy at the age of 13 and saw service in the South Atlantic and the West Indies. By 1745 he had received his first command. In June 1755 he captured a French vessel off the mouth of the St. Lawrence River, thus firing the first formal exchange of the French and Indian War. On the death of his older brother in 1758, he became Viscount Howe in the Irish peerage. He served on the Admiralty Board and as treasurer of the navy. On the eve of the American Revolution, in 1775, he was advanced to the rank of vice admiral. Howe and his younger brother, Gen. William Howe, played important parts in the American Revolution. They had a difficult mission: they were to crush the rebels militarily but also negotiate restoration of peace. The British armies, under William Howe, were generally successful in the summer and fall of 1776, but they failed to crush the colonial army. And the colonists, having declared independence in 1776, refused to negotiate on terms that implied willingness to submit to British control. In 1776 and 1777 Richard Howe's fleet was limited to transporting and supplying the army under his brother's command. The admiral's only notable contribution came in August 1778, when his forces roughed up several French vessels, thus helping prevent a cooperative Franco-American attack on the British forces at Newport, R.I. Frustrated by continuing American resistance, irked by criticism at home, and feeling he had not received adequate support, Richard Howe resigned his command in October 1778. In the succeeding months a pamphlet war over the American Revolution was waged in England, culminating in an inconclusive parliamentary investigation. Meanwhile, Howe refused to serve under the existing ministry. In 1782 Howe was granted a new command, promoted in rank, and made a British peer—Viscount Howe of Langar. These signs of confidence were justified by his relief of Gibraltar in October in the face of superior French numbers. From 1783 to 1788 he served as first lord of the Admiralty. He was created Earl Howe in 1788. In 1793, after the start of the French Revolutionary Wars, Howe was put in command of the Channel fleet. The following year, when a French fleet attempted to prevent him from intercepting a convoy of provisions headed toward Brest from the United States, there occurred the series of high-sea engagements off Ushant collectively known as the "Battle of the Glorious First of June." The British victory, though not total, was great and caught the imagination of the public. Howe helped negotiate a settlement in a naval mutiny at Spithead in 1797. He died on Aug. 5, 1799, in London. Further Reading on Richard Howe The most thorough study of Howe in America is Troyer S. Anderson, The Command of the Howe Brothers during the American Revolution (1936). Most of the family papers were destroyed by fire.
Why a fun approach to learning is so important15/09/2017 A question often asked at swimming lessons across the country is “Why is my child just playing games? They aren’t learning.” We can categorically say that this is a complete myth. A fun approach to learning is so important for children and adults alike, whether for swimming lessons or for any other learning opportunity. This is the approach that we adopt for the Swim England Learn to Swim Programme. Learning through fun and games The easiest way for a child to acquire the skills needed to be a confident swimmer is through fun and games. Games are an ideal way for children to develop their jigsaw of skills and may even lead to them learning how to combine one skill with another, without even realising. The Swim England Learn to Swim Programme takes this approach to learning to swim, giving swimmers the core skills needed to become competent swimmers. To illustrate this, during Learn to Swim Stage 2, children will play ‘dinner on a plate’, where they hold a float with a small toy on top, travelling through the water making sure it doesn’t fall off. Not only is this a game that children love, it also provides an incentive for them to travel, building their buoyancy and balance, and travel and co-ordination, two important core aquatic skills for all children learning to swim. Each skill counts At each stage of the programme, all of the skills learned are crucial and must be achieved easily and without stress. For example, if the swimmer does not accomplish a skill such as aquatic breathing, the achievement of skills such as rotation, streamlining, travel, buoyancy and balance will become difficult to perform effectively. 9 core skills of swimming The core skills of swimming are the basic skills your child needs to keep afloat in water and to get ready to start swimming - Buoyancy and Balance - Rotation and Orientation - Aquatic Breathing - Travel and Coordination - Water Safety - Health and Fitness Through the journey of acquiring these skills, water competence will develop. Through competence in water, the child will have more fun, will be more likely to be active, follow a healthy lifestyle and participate in sport throughout his or her lifetime. This process ultimately results in a child being able to swim different strokes, such as front crawl, breaststroke, backstroke and butterfly, as well as learning skills that may become transferable to another water-based or land-based sport. Examples include developing throwing and catching for water polo, which is transferable to sports such as netball and basketball. Skills such as the somersault may develop a swimmer’s ability to take part in synchronised swimming but could also be used in gymnastics. The Swim England Awards celebrate swimming milestones for the children as they achieve a specific skill, distance or complete a Learn to Swim Stage Award. This adds the star dust for the child – we all enjoy getting recognition for our achievements! The time it takes for a swimmer to develop the crucial skills and build their jigsaw of skills will depend on their own personal development, as swimmers progress at their own pace. Parents and swimming teachers play a key role in keeping them motivated by ensuring that they continue to enjoy being in the water and learning to swim.
OpenStax Biology 2e The elucidation of the structure of the double helix provided a hint as to how DNA divides and makes copies of itself. In their 1953 paper, Watson and Crick penned an incredible understatement: “It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.” With specific base pairs, the sequence of one DNA strand can be predicted from its complement. The double-helix model suggests that the two strands of the double helix separate during replication, and each strand serves as a template from which the new complementary strand is copied. What was not clear was how the replication took place. There were three models suggested: conservative, semi-conservative, and dispersive. In conservative replication, the parental DNA remains together, and the newly formed daughter strands are together. The semi-conservative method suggests that each of the two parental DNA strands acts as a template for new DNA to be synthesized; after replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand. In the dispersive model, both copies of DNA have double-stranded segments of parental DNA and newly synthesized DNA interspersed. Meselson and Stahl were interested in understanding how DNA replicates. They grew E. coli for several generations in a medium containing a “heavy” isotope of nitrogen (15N), which gets incorporated into nitrogenous bases, and eventually into the DNA. The E. coli culture was then placed into medium containing 14N and allowed to grow for several generations. After each of the first few generations, the cells were harvested and the DNA was isolated, then centrifuged at high speeds in an ultracentrifuge. During the centrifugation, the DNA was loaded into a gradient (typically a solution of salt such as cesium chloride or sucrose) and spun at high speeds of 50,000 to 60,000 rpm. Under these circumstances, the DNA will form a band according to its buoyant density: the density within the gradient at which it floats. DNA grown in 15N will form a band at a higher density position (i.e., farther down the centrifuge tube) than that grown in 14N. Meselson and Stahl noted that after one generation of growth in 14N after they had been shifted from 15N, the single band observed was intermediate in position in between DNA of cells grown exclusively in 15N and 14N. This suggested either a semi-conservative or dispersive mode of replication. The DNA harvested from cells grown for two generations in 14N formed two bands: one DNA band was at the intermediate position between 15N and 14N, and the other corresponded to the band of 14N DNA. These results could only be explained if DNA replicates in a semi-conservative manner. And for this reason, therefore, the other two models were ruled out. During DNA replication, each of the two strands that make up the double helix serves as a template from which new strands are copied. The new strands will be complementary to the parental or “old” strands. When two daughter DNA copies are formed, they have the same sequence and are divided equally into the two daughter cells. How is DNA Replicated? Replication occurs in three major steps: the opening of the double helix and separation of the DNA strands, the priming of the template strand, and the assembly of the new DNA segment. During separation, the two strands of the DNA double helix uncoil at a specific location called the origin. Several enzymes and proteins then work together to prepare, or prime, the strands for duplication. Finally, a special enzyme called DNA polymerase organizes the assembly of the new DNA strands. The following description of this three-stage process applies generally to all cells, but specific variations within the process may occur depending on organism and cell type. Clark, M., Douglas, M., Choi, J. Biology 2e. Houston, Texas: OpenStax. Access for free at: https://openstax.org/details/books/biology-2e Research Abstract: Origins of DNA replication In all kingdoms of life, DNA is used to encode hereditary information. Propagation of the genetic material between generations requires timely and accurate duplication of DNA by semiconservative replication prior to cell division to ensure each daughter cell receives the full complement of chromosomes. DNA synthesis of daughter strands starts at discrete sites, termed replication origins, and proceeds in a bidirectional manner until all genomic DNA is replicated. Despite the fundamental nature of these events, organisms have evolved surprisingly divergent strategies that control replication onset. Here, we discuss commonalities and differences in replication origin organization and recognition in the three domains of life. https://doi.org/10.1371/journal.pgen.1008320 Cell Size and the Initiation of DNA Replication in Bacteria In eukaryotes, DNA replication is coupled to the cell cycle through the actions of cyclin-dependent kinases and associated factors. In bacteria, the prevailing view, based primarily from work in Escherichia coli, is that growth-dependent accumulation of the highly conserved initiator, DnaA, triggers initiation. However, the timing of initiation is unchanged in Bacillus subtilis mutants that are ∼30% smaller than wild-type cells, indicating that achievement of a particular cell size is not obligatory for initiation. Prompted by this finding, we re-examined the link between cell size and initiation in both E. coli and B. subtilis. Although changes in DNA replication have been shown to alter both E. coli and B. subtilis cell size, the converse (the effect of cell size on DNA replication) has not been explored. Here, we report that the mechanisms responsible for coordinating DNA replication with cell size vary between these two model organisms. In contrast to B. subtilis, small E. coli mutants delayed replication initiation until they achieved the size at which wild-type cells initiate. Modest increases in DnaA alleviated the delay, supporting the view that growth-dependent accumulation of DnaA is the trigger for replication initiation in E. coli. Significantly, although small E. coli and B. subtilis cells both maintained wild-type concentration of DnaA, only the E. coli mutants failed to initiate on time. Thus, rather than the concentration, the total amount of DnaA appears to be more important for initiation timing in E. coli. The difference in behavior of the two bacteria appears to lie in the mechanisms that control the activity of DnaA. https://doi.org/10.1371/journal.pgen.1002549 An Increase in Mitochondrial DNA Promotes Nuclear DNA Replication in Yeast Coordination between cellular metabolism and DNA replication determines when cells initiate division. It has been assumed that metabolism only plays a permissive role in cell division. While blocking metabolism arrests cell division, it is not known whether an up-regulation of metabolic reactions accelerates cell cycle transitions. Here, we show that increasing the amount of mitochondrial DNA accelerates overall cell proliferation and promotes nuclear DNA replication, in a nutrient-dependent manner. The Sir2p NAD+-dependent de-acetylase antagonizes this mitochondrial role. We found that cells with increased mitochondrial DNA have reduced Sir2p levels bound at origins of DNA replication in the nucleus, accompanied with increased levels of K9, K14-acetylated histone H3 at those origins. Our results demonstrate an active role of mitochondrial processes in the control of cell division. They also suggest that cellular metabolism may impact on chromatin modifications to regulate the activity of origins of DNA replication. https://doi.org/10.1371/journal.pgen.1000047 DNA Replication Control Is Linked to Genomic Positioning of Control Regions in Escherichia coli Chromosome replication in Escherichia coli is in part controlled by three non-coding genomic sequences, DARS1, DARS2, and datA that modulate the activity of the initiator protein DnaA. The relative distance from oriC to the non-coding regions are conserved among E. coli species, despite large variations in genome size. Here we use a combination of i) site directed translocation of each region to new positions on the bacterial chromosome and ii) random transposon mediated translocation followed by culture evolution, to show genetic evidence for the importance of position. Here we provide evidence that the genomic locations of these regulatory sequences are important for cell cycle control and bacterial fitness. In addition, our work shows that the functionally redundant DARS1 and DARS2 regions play different roles in replication control. DARS1 is mainly involved in maintaining the origin concentration, whether DARS2 is also involved in maintaining single cell synchrony. https://doi.org/10.1371/journal.pgen.1006286 Multiple Regulatory Systems Coordinate DNA Replication with Cell Growth in Bacillus subtilis In many bacteria the rate of DNA replication is linked with cellular physiology to ensure that genome duplication is coordinated with growth. Nutrient-mediated growth rate control of DNA replication initiation has been appreciated for decades, however the mechanism(s) that connects these cell cycle activities has eluded understanding. In order to help address this fundamental question we have investigated regulation of DNA replication in the model organism Bacillus subtilis. Contrary to the prevailing view we find that changes in DnaA protein level are not sufficient to account for nutrient-mediated growth rate control of DNA replication initiation, although this regulation does require both DnaA and the endogenous replication origin. We go on to report connections between DNA replication and several essential cellular activities required for rapid bacterial growth, including respiration, central carbon metabolism, fatty acid synthesis, phospholipid synthesis, and protein synthesis. Unexpectedly, the results indicate that multiple regulatory systems are involved in coordinating DNA replication with cell physiology, with some of the regulatory systems targeting oriC while others act in a oriC-independent manner. We propose that distinct regulatory systems are utilized to control DNA replication in response to diverse physiological and chemical changes. https://doi.org/10.1371/journal.pgen.1004731
Questions from a scientific viewpoint that challenge the theory of Evolution. Used with the kind permission of Creation Ministries International, www.creation.com and taken from their booklet of the same name. 1. HOW DID LIFE ORIGINATE? Evolutionist Professor Paul Davies admitted, “Nobody knows how a mixture of lifeless chemicals spontaneously organized themselves into the first living cell.” Andrew Knoll, professor of biology, Harvard, said, “we don’t really know how life originated on this planet”. A minimal cell needs several hundred proteins. Even if every atom in the universe were an experiment with all the correct amino acids present for every possible molecular vibration in the supposed evolutionary age of the universe, not evenone average-sized functional protein would form. So how did life with hundreds of proteins originate just by chemistry without intelligent design? 2. HOW DID THE DNA CODE ORIGINATE? The code is a sophisticated language system with letters and words where the meaning of the words is unrelated to the chemical properties of the letters—just as the information on this page is not a product of the chemical properties of the ink (or pixels on a screen). What other coding system has existed without intelligent design? How did the DNA coding system arise without it being created? 3. HOW COULD MUTATIONS—ACCIDENTAL COPYING MISTAKES (DNA ‘LETTERS’ EXCHANGED, DELETED OR ADDED, GENES DUPLICATED, CHROMOSOME INVERSIONS, ETC.)—CREATE THE HUGE VOLUMES OF INFORMATION IN THE DNA OF LIVING THINGS? How could such errors create 3 billion letters of DNA information to change a microbe into a microbiologist? There is information for how to make proteins and also for controlling their use—much like a cookbook contains the ingredients as well as the instructions for how and when to use them. One without the other is useless. See creation.com/meta-information. Mutations are known for their destructive effects, including over 1,000 human diseases such as hemophilia. Rarely are they even helpful. But how can scrambling existing DNA information create a new biochemical pathway or nano-machines with many components, to make ‘goo-to-you’ evolution possible? E.g., How did a 32-component rotary motor like ATP synthase (which produces the energy currency, ATP, for all life), or robots like kinesin (a ‘postman’ delivering parcels inside cells) originate? 4. WHY IS NATURAL SELECTION, A PRINCIPLE RECOGNIZED BY CREATIONISTS, TAUGHT AS ‘EVOLUTION’, AS IF IT EXPLAINS THE ORIGIN OF THE DIVERSITY OF LIFE? By definition it is a selective process (selecting from already existing information), so is not a creative process. It might explain the survival of the fittest (why certain genes benefit creatures more in certain environments), but not the arrival of the fittest (where the genes and creatures came from in the first place). The death of individuals not adapted to an environment and the survival of those that are suited does not explain the origin of the traits that make an organism adapted to an environment. E.g., how do minor back-and-forth variations in finch beaks explain the origin of beaks or finches? How does natural selection explain goo-to-you evolution? 5. HOW DID NEW BIOCHEMICAL PATHWAYS, WHICH INVOLVE MULTIPLE ENZYMES WORKING TOGETHER IN SEQUENCE, ORIGINATE? Every pathway and nano-machine requires multiple protein/enzyme components to work. How did lucky accidents create even one of the components, let alone 10 or 20 or 30+ at the same time, often in a necessary programmed sequence? Evolutionary biochemist Franklin Harold wrote, “we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations.” 6. LIVING THINGS LOOK LIKE THEY WERE DESIGNED, SO HOW DO EVOLUTIONISTS KNOW THAT THEY WERE NOT DESIGNED? Richard Dawkins wrote, “biology is the study of complicated things that have the appearance of having been designed with a purpose.” Francis Crick, the codiscoverer of the double helix structure of DNA, wrote, “Biologists must constantly keep in mind that what they see was not designed, but rather evolved.” The problem for evolutionists is that living things show too much design. Who objects when an archaeologist says that pottery points to human design? Yet if someone attributes the design in living things to a designer, that is not acceptable. Why should science be restricted to naturalistic causes rather than logical causes? 7. HOW DID MULTI-CELLULAR LIFE ORIGINATE? How did cells adapted to individual survival ‘learn’ to cooperate and specialize (including undergoing programmed cell death) to create complex plants and animals? 8. HOW DID SEX ORIGINATE? Asexual reproduction gives up to twice as much reproductive success (‘fitness’) for the same resources as sexual reproduction, so how could the latter ever gain enough advantage to be selected? And how could mere physics and chemistry invent the complementary apparatuses needed at the same time (non-intelligent processes cannot plan for future coordination of male and female organs) 9. WHY ARE THE (EXPECTED) COUNTLESS MILLIONS OF TRANSITIONAL FOSSILS MISSING? Darwin noted the problem and it still remains. The evolutionary family trees in textbooks are based on imagination, not fossil evidence. Famous Harvard paleontologist (and evolutionist), Stephen Jay Gould, wrote, “The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology”. Other evolutionist fossil experts also admit the problem. creation.com/pattquote creation.com/multicellularity See: creation.com/evoquest for supporting references. Evolution: the naturalistic origin of life and its diversity. 10. HOW DO ‘LIVING FOSSILS’ REMAIN UNCHANGED OVER SUPPOSED HUNDREDS OF MILLIONS OF YEARS, IF EVOLUTION HAS CHANGED WORMS INTO HUMANS IN THE SAME TIME FRAME? Professor Gould wrote, “the maintenance of stability within species must be considered as a major evolutionary problem.” 11. HOW DID BLIND CHEMISTRY CREATE MIND/ INTELLIGENCE, MEANING, ALTRUISM AND MORALITY? If everything evolved, and we invented God, as per evolutionary teaching, what purpose or meaning is there to human life? Should students be learning nihilism (life is meaningless) in science classes? 12. WHY IS EVOLUTIONARY ‘JUST-SO’ STORYTELLING TOLERATED? Evolutionists often use flexible story-telling to ‘explain’ observations contrary to evolutionary theory. NAS (USA) member Dr Philip Skell wrote, “Darwinian explanations for such things are often too supple: Natural selection makes humans self-centered and aggressive—except when it makes them altruistic and peaceable. Or natural selection produces virile men who eagerly spread their seed—except when it prefers men who are faithful protectors and providers. When an explanation is so supple that it can explain any behavior, it is difficult to test it experimentally, much less use it as a catalyst for scientific discovery.” 13. WHERE ARE THE SCIENTIFIC BREAKTHROUGHS DUE TO EVOLUTION? Dr Marc Kirschner, chair of the Department of Systems Biology, Harvard Medical School, stated: “In fact, over the last 100 years, almost all of biology has proceeded independent of evolution, except evolutionary biology itself. Molecular biology, biochemistry, physiology, have not taken evolution into account at all.” Dr Skell wrote, “It is our knowledge of how these organisms actually operate, not speculations about how they may have arisen millions of years ago, that is essential to doctors, veterinarians, farmers ….” Evolution actually hinders medical discovery. Then why do schools and universities teach evolution so dogmatically, stealing time from experimental biology that so benefits humankind? 14. SCIENCE INVOLVES EXPERIMENTING TO FIGURE OUT HOW THINGS WORK; HOW THEY OPERATE. WHY IS EVOLUTION, A THEORY ABOUT HISTORY, TAUGHT AS IF IT IS THE SAME AS THIS OPERATIONAL SCIENCE? You cannot do experiments, or even observe what happened, in the past. Asked if evolution has been observed, Richard Dawkins said, “Evolution has been observed. It’s just that it hasn’t been observed while it’s happening.” 15. WHY IS A FUNDAMENTALLY RELIGIOUS IDEA, A DOGMATIC BELIEF SYSTEM THAT FAILS TO EXPLAIN THE EVIDENCE, TAUGHT IN SCIENCE CLASSES? Karl Popper, famous philosopher of science, said “Darwinism is not a testable scientific theory, but a metaphysical [religious] research programme ….” Michael Ruse, evolutionist science philosopher admitted, “Evolution is a religion. This was true of evolution in the beginning, and it is true of evolution still today.” If “you can’t teach religion in science classes”, why is evolution taught?
Presentation on theme: "Polya’s Four Step Problem Solving Process"— Presentation transcript: 1 Polya’s Four Step Problem Solving Process Have A Problem???“How To Solve It!”Polya’s Four Step Problem Solving Process 2 Fair Use GuidelinesCertain materials are included under the fair use exemption of the U. S. Copyright Law and have been prepared according to the educational fair use guidelines. 3 Today’s TEKS Objective: The student is expected to:(B) use a problem-solving model that incorporates understanding the problem, making a plan, carrying out the plan, and evaluating the solution for reasonableness(C) select or develop an appropriate problem-solving strategy from a variety of different types, including drawing a picture, looking for a pattern, systematic guessing and checking, acting it out, making a table, working a simpler problem, or working backwards to solve a problem(8.14) Underlying processes and mathematical tools.The student applies Grade 8 mathematics to solve problems connected to everyday experiences, investigations in other disciplines, and activities in and outside of school. 4 Why Problem Solving??Once, at an informal meeting, a social scientist asked a math professor, “What’s the main goal of teaching mathematics?” The reply was, “Problem solving.”In return, the mathematician asked, “What is the main goal of teaching the social sciences?” Once more the answer was, “Problem solving.” 5 Who Solves Problems??All successful engineers, scientists, social scientists, lawyers, accountants, doctors, business managers, and so on, have to be good problem solvers.Although the problems that people encounter may be very diverse, there are common elements and an underlying structure that can help to facilitate problem solving. 6 Step 1: Understand the Problem Identify what you are trying to find.Summarize the information that is available in your own words.Determine if the information available is enough, ie. Do you need a formula, etc.?Strip the problem of irrelevant details.Don’t impose conditions that do not exist. 7 Step 2: Devise a PlanIs this problem similar to another problem you have solved?Can one of the Problem Solving Strategies be used?Often a considerable amount of creativity is required to formulate a plan. 8 Strategies for Problem Solving A Strategy is defined as an artful means to an end. Make a chart or table.Look for a pattern.Draw a picture or diagram.Eliminate impossible situations.Work Backwards.Guess, test, and revise.Use a variable.Design a model.Try a simpler version of the problem.Use reasoning. 9 Step 3: Carry Out the Plan Implement the strategy or strategies that you have chosen until the problem is solved or until a new course of action is suggested.Give yourself a reasonable amount of time in which to solve the problem. If you are not successful, seek hints from others or put the problem aside for awhile.Don’t expect to solve correctly and immediately all problems. Problem Solving takes time and persistence.Don’t be afraid of starting over. Often, a fresh start and a new strategy will lead to success. 10 Step 4: Look BackInterpret the results into a sentence with your own words.Check the results to be sure the solution is correct.Does your answer satisfy the statement of the problem? Does it make sense?Ask if there is another way to solve the problem.Ask if there are other problems that can be solved by using the same techniques used in this problem.Make a point of thinking about the strategy that finally worked for this type of problem for future reference. 11 A Sample of the Process in Action Problem:Find the sum ofLet’s try Step 1:Understand the Problem 12 Step 1: Understand the Problem This problem will require getting a common denominator, here 210, converting each fraction, and finding the sum of the numerators.This is obviously a long and tedious process.Maybe there is a quicker way to solve the problem... 13 Step 2: Devise a PlanInstead of doing a direct calculation, let’s combine some of the suggested strategies.Namely, make a list of the first few sums and look for a pattern. 14 Step 3: Carry Out the Plan The pattern of sums,suggests that the sum of the ten fractions is 15 Step 4: Look BackThis method of combining the strategy of Solve a Simpler Problem with Make a List and Look for a Pattern is very useful.For example, what is the sumBecause of the large denominators, you wouldn’t want to add these fractions directly. 16 Problem Solving Recap...When presenting the problem solving process and the sample problem, great care was taken to label and display each of the four steps. Clearly, this is not necessary every time you work a problem.On the other hand, it is a good idea to get into the habit of recalling the four steps as you plan and as you work through a problem.The steps and strategies will be especially helpful when you are making a plan.As you are planning to solve a problem, think of the strategies as a collection of tools which you may select from and utilize to successfully solve your problem. 17 Final Suggestions from Successful Problem Solvers Accept the challenge of solving a problem.Take time to explore, reflect, think, …Talk to yourself. Ask yourself lots of questions.Many problems require an incubation period. If you get frustrated, do not hesitate to take a break - your subconscious may take over. But do return to try again.Experience in problem solving is very valuable. Work lots of problems; your confidence will grow.There is nothing like a breakthrough, an “Aha!”, as you solve your problems.Always, always look back. Try to see precisely what the key step was in your solution and make a mental note for future reference.Enjoy yourself! Solving a problem is a positive experience. 18 Credits: John P. Ashby PowerPoint Presentation by… Course: ED 488 Instructor: Susan PrideSemester: Fall, 1999Date: November 11, 1999Title: How To Solve ItSoftware Package: Microsoft PowerPoint
Eusociality is a term in animal behaviour for the more complex kinds of social organisation. The term "eusocial" was introduced in 1966 by Suzanne Batra. E.O. Wilson gave it a more precise meaning. Meaning of the term[change \| change source] - Different animals have different jobs to do. There is a division of labour. Some castes may be sterile. - Animal generations overlap. There are different generations in the hive or nest. - Animals cooperate to care for the young. Definition debates[change \| change source] Examples[change \| change source] The most familiar examples of eusociality are insects such as ants, bees, wasps, and termites. All of these are colonial animals which have queens for reproduction. The animals that are workers or soldiers are usually sterile--they cannot have offspring. Eusociality with sterile individuals is the most extreme form of kin altruism. They do specialized tasks, often caring for the reproductive members. It includes individuals whose behaviour, body shape and function is modified for group defence, including self-sacrifice (altruism). Eusociality played a key role in the development of theories in sociobiology. Naked mole rat[change \| change source] Naked mole rats are eusocial mammals. Colonies averaging 75-80 individuals live together in complex systems of burrows in arid African deserts. The tunnel systems built by naked mole rats can stretch up to two or three miles in cumulative length. Other examples[change \| change source] Recently, some species of gall-making aphids (Order Hemiptera) and thrips (Order Thysanoptera) are eusocial, with many separate origins of the state (convergent evolution). These species have extremely high relatedness between individuals. This is due to their mode of reproduction: sterile soldier castes are of the same clone as the reproducing female. The gall-inhabiting behavior gives these species a resource which sets them apart from related species with similar genetics. In these groups, therefore, high relatedness alone does not lead to the evolution of social behavior, but requires that groups occur in a restricted, shared area. Similarly, eusociality occurs in some crustaceans and other arthropods. On some tropical reefs, several species of minute Synalpheus pistol shrimp are eusocial. They depend on certain sponges for the survival of their colony, and have a single breeding female and a number of of male defenders armed with large snapping claws. Again, there is a single shared domicile for the colony members, and the non-breeding members act to defend it. [change \| change source] In colonies of eusocial animals, some animals are sterile. They can not pass on their genes at all. How can these animals evolve and persist? Since they do not breed, their fitness should be zero and any genes causing this condition should be eliminated from the population immediately. In On the Origin of Species, Darwin called this eusocial behavior the "one special difficulty, which at first appeared to me insuperable, and actually fatal to my theory". Darwin thought that the resolution to the paradox would lie in the close family relationship. Darwin could not say more because he did no know what the mechanism of heredity was. The first explanations were kin selection, and inclusive fitness. Both rely on the discovery of how genes are inherited. This discovery was made after Darwin had published On the Origin of Species, and not understood until after 1900. Early ideas on eusociality included suggestions that trophallaxis or food sharing was a basis for sociality. The most widely accepted model to explain eusociality is based on W.D. Hamilton's idea of inclusive fitness. Inclusive fitness[change \| change source] In this system, sex is determined by the number of sets of chromosomes an individual receives. An offspring formed from the union of a sperm and an egg develops as a female, and an unfertilized egg develops as a male. This means that the males have half the number of chromosomes that a female has, and so are haploid. The haplodiploid sex-determination system has a number of peculiarities. Most importantly, the relatedness between the sisterhood of worker bees in a hive or nest is 0.75. This means the workers are significantly more closely related than siblings in other sex determination systems. It is this point which drives the kin selection theory of how eusociality evolved.p465 Consequences[change \| change source] If the theory of inclusive fitness is accurate, the haplodiploidy makes kin selection easier. Sisters are more related to each other than to any offspring they might have. Hamilton called them supersisters. On average, two supersisters have 75 percent of the same genes. If they breed, they would share only half of their genome with their offspring. From the selfish gene's point-of-view, it is better to raise more sisters. Even though workers often do not reproduce, they are potentially passing on more of their genes by caring for sisters than they would by having their own offspring. This unusual situation may explain why eusociality evolved several times in the haplodiploid group Hymenoptera — ants, bees and wasps. As of 2009, 11 separate cases are known. However, Hymenoptera is a large group and the majority of its species are not social. Furthermore, highly developed eusociality also exists in non-hymenopterans, perhaps most obviously in termites. Most such cases involve organisms that display high levels of inbreeding, so that colony members share more than half of their genes. Therefore the same model is considered to apply to these species. Reeve and Holldobler put forward a theory of a superorganism. They look at competition and co-operation between groups as well as within groups. In their model, an individual's inclusive fitness varies according to how much it invests in within-group competition (e.g. hoarding a private food cache) versus between-group competition (e.g. contributing to common foraging); and on its relatedness to the other group members. In a colony with one breeder (queen) and many workers, the evolutionarily stable state is for each individual to invest entirely in helping the group. This leads to a perfect "superorganism". In other words, the eusociality is stable, a result that agrees with Hamilton's findings. Also, they show that the effect is reinforced if there are many groups competing for the same resources. Related pages[change \| change source] References[change \| change source] - Batra S.W.T. 1966. Nests and social behavior of halictine bees of India (Hymenoptera: Halictidae). Indian J. Entomol 28 375-393. - Wilson E.O. 1971. The insect societies. Harvard University Press. Cambridge. Massachusetts. - Michener C.D. 1969. Ann. Rev. Entomol. 14, 299-342. - Gadagkar, Raghavendra 1993. And now... eusocial thrips!. Current Science 64(4) 215-216. PDF - Crespi B.J. and Yanega D. 1995. The definition of eusociality. Behav. Ecol. 6, 109–115 - Kevin R. Foster & Francis L.W. Ratnieks 2005. A new eusocial vertebrate? Trends in Ecology and Evolution 20(7):363-364 PDF - James T. Costa & Terrence D. Fitzgerald 2005. Social terminology revisited: where are we ten years later? Ann. Zool. Fennici 42:559-564 PDF - Burda H. Honeycutt R.L. Begall S. Locker-Grutjen O & Scharff A. 2000. Are naked and common mole-rats eusocial and if so, why? Behavioral Ecology and Sociobiology 47 293-303 Abstract - Dawkins, Richard (1976). The Selfish Gene. Oxford University Press. ISBN 0-19-286092-5. - Crespi B.J. 1992 Eusociality in Australian gall thrips. Nature 359: 724-726. - Duffy, J. Emmett; Cheryl L. Morrison and Ruben Rios (2000). "Multiple origins of eusociality among sponge-dwelling shrimps (Synalpheus)". Evolution 54 (2): 503-516. - Duffy, J. E (1998). "On the frequency of eusociality in snapping shrimps (Decapoda : Alpheidae), with description of a second eusocial species". Bulletin of marine science 63 (2): 387-400. - Darwin, Charles 1859. The origin of species. London:Murray. Chapter 7, p236 - Costa, James T. 2009. The annotated origin. Harvard, p236. - Wheeler W.M. 1918. A study of some ant larvae with a consideration of the origin and meaning of social habits among insects. Proc. Am. Phil. Soc. 57, 293-343. - Hamilton, William D. 1996. Narrow roads of geneland. Freeman. Chapter 2, Hamilton's rule pp 14–30. - Grimaldi D. and Engel M.S. 2005. The evolution of the insects. Cambridge University Press. ISBN 0-521-82149-5 - The relatedness of siblings is usually 0.5. - Hamilton W.D. 1964. The genetical evolution of social behaviour, I and II. Journal of Theoretical Biology 7, 1–52. Reprinted with comments in Hamilton W.D. 1996. Narrow roads of geneland, volume I Evolution of social behaviour. Freeman/Spektrum, Oxford. ISBN 0-7167-4530-5 - Hughes W.O.H. et al (2008). "Ancestral monogamy shows kin selection is key to the evolution of eusociality". Science 320 (5880): 1213–1216. doi:10.1126/science.1156108. PMID 18511689. http://www.sciencemag.org/cgi/content/abstract/320/5880/1213. Retrieved 2008-08-04. - Reeve H.K. and Hölldobler B. 2007. The emergence of a superorganism through intergroup competition. Proceedings of the National Academy of Sciences 104: 9736-9740
Diabetes is spreading like a bushfire across the globe, but even if governments, doctors, and health authorities have tried desperately to bend the curve, they have not succeeded so far. On the contrary. Today, diabetes is controlled with help from different medical drugs that do not address the underlying cause and actually affect or organ systems. Because of this, diabetics often have impaired quality of life and shorter lifespans than healthy individuals. What is more, diabetics have widespread vitamin B12 and vitamin D deficiencies, which are associated with diabetic neuropathy, which is a serious complication. Cholesterol-lowering drugs (statins) are also linked to reduced levels of Q10, a compound that is necessary for energy turnover, the heart, and the cardiovascular system. Around 415 million humans globally are affected by diabetes, and the number is expected to grow to 642 million by 2040. An even greater number have early stages of the disease like insulin resistance and metabolic syndrome without knowing it. Diabetes affects the majority of organ systems, and damage to the heart, kidneys, and blood vessels are a direct cause of impaired quality of life, shorter lifespan, and enormous health care costs. Diabetic neuropathy is caused by inflammation and damage to the nervous system that controls our cardiovascular function. The damage typically affects the nerves and blood vessels in the feet and legs, in some cases leading to amputations. It can also affect urination, bowel control, and sexual function. Diabetic neuropathy is insidious and is often overlooked because the symptoms do not show until the late stages of the disease. Diabetic neuropathy is associat4ed with an increased risk of morbidity and mortality caused by failing circulation and other factors. \|Diabetic neuropathy is associated with increased morbidity, amputations, and premature death. It is also known as diabetic cardiac autonomic neuropathy (CAN)\| Diabetic neuropathy is preventable in its early stages Smoking, elevated cholesterol levels, and hypertension are risk factors of diabetic neuropathy. An estimated 20-60 percent of diabetics suffer from this complication. In its late stages, diabetic neuropathy is irreversible, and nothing can stop it. However, the condition has been seen to be reversible in its early stages, and one can even stop it from progressing. It is therefore of vital importance to explore potential risk factors and look closer at ways to prevent this complication. Lack of vitamin B12 and vitamin D are linked to diabetic neuropathy According to research carried out by Christian Stevns Hansen, a Danish physician, low levels of vitamin B12 and vitamin D are linked to an increased risk of diabetic neuropathy. Vitamin B12 is a vital building block of cells and their DNA, and the vitamin is also important for the nervous system, for energy levels, and for blood formation. People with type 2 diabetes are at increased risk of lacking vitamin B12, which is because their condition is often treated with metformin, a medical drug that blocks the body’s vitamin B12 uptake. The link between vitamin B12 and diabetic neuropathy was shown in a study of 469 type 2 diabetics from a diabetes treatment center. The results revealed a significant and linear correlation between vitamin B12 levels and diabetic neuropathy plus several other markers of cardiac nerve function. In other words, lack of vitamin B12 was associated with impaired nerve function. Levels of vitamin D in the blood are also associated with an inreased risk of developing diabetic neuropathy. For instance, vitamin D is important for controlling genes and inflammation. Christian Stevns Hansen and his team of scientists studies 13 patients with type 1 and type 2 diabetes and found an inverse U-shaped relation meaning that both high and low levels of vitamin D were linked to impaired nerve function. Other studies show that diabetics have difficulty with utilizing vitamin D, and that magnesium is requried to activate vitamin D precursors from the sun, from dietary sources, and from supplements. New perspectives in the prevention and treatment of diabetic neuropathy Christian Stevns Hansen’s research points to inexpensive and safe vitamin supplements as a new potential treatment for diabetic neuropathy. If further studies show the expected results, screening and treating diabetes patients for vitamin D and vitamin B12 deficiencies may be the future. Not only will this benefit the individual patient, it will also be a boon to society in general. According to an earlier American study, people with higher blood levels of vitamin D are far less likely to develop type 2 diabetes and metabolic syndrome (an early stage of type 2 diabetes), which is characterized by insulin resistance, elevated blood pressure, and elevated cholesterol levels. It takes many years for type 2 diabetes to develop, so it is really important that you make sure to have sufficiently high blood levels of vitamin D at all times. According to existing research, it is impossible to obtain the required levels of vitamin D without generous sun exposure during the summer period and high-dosed vitamin D supplements during the winter. Your practitioner can measure your levels of B12 and vitamin D to make sure they are sufficiently high. Diabetes, cholesterol-lowering medicine and Q10 Diabetes and metabolic syndrome are linked to elevated cholesterol levels, which is treated with cholesterol-lowering drugs (statins) that work by blocking HMG-CoA (a liver enzyme). This enzyme is also involved in the synthesis of coenzyme Q10. Therefore, statins inhibit the body’s endogenous Q10 synthesis, which is problematic as Q10 is in cellular energy turnover and works as a powerful antioxidant. The impaired Q10 synthesis tends to affect organs that depend greatly on energy such as the heart, the muscles, and the nervous system. Statins are known to cause a host of side effects such as fatigue, poor concentration, muscle pain, and lack of vitality. Other side effects may eventually turn up because Q10 is a very important antioxidant that counteracts oxidative stress, which is a caused by a free radical overload. Diabetes in itself increased the risk of oxidative stress, which is a particularly big problem in diabetic neuropathy. A large review article has shown that daily supplementation with 100 mg of Q10 for three months significantly reduced inflammation in diabetic neuropathy. Another study has shown that 200 mg of Q10 daily for three months reduces oxidative stress and the risk of complications such as atherosclerosis and cardiovascular disease. Also, the use of statins (simvastatin in particular) increased the risk of type 2 diabetes by 10-40 percent. In fact, it is a bit ironic that statins increase the risk of diabetes, which in itself increases the risk of atherosclerosis and heart failure. \|Q10 supplements generally have poor bioavailability. Make sure to buy a product with documented bioavailability so you don’t waste your money\| Christian Stevns Hansen. Almindelige vitaminer og mineraler er forbundne med alvorlige komplikationer hos diabetes patienter. Formidling af Ph.d. afhandlingen: Exploring new risk markers for diabetic cadiovascular autnomic neuropathy. Scott LaFee. Vitamin D Deficiency Linked to Greater Risk of Diabetes. UC San Diego Health. April 2018 Plasma 25-hydroxyvitamin concentration and risk of type 2 diabetes and pre-diabetes. 12-year cohort study. PLoS One 2018 Eneida Boteon Schmitt et al. Vitamin D deficiency is associated with metabolic syndrome in postmenopausal women. Maturitas 2018 Qi Dai el al. Abstract CT093: Bimodal relationship between magnesium supplementation and vitamin D status and metabolism: Results from randomized trial. Cancer Research July 2018 Anne Marie Uwitonze, Mohammed S Razzaque. Role of magnesium in Vitamin D Activation and Function. The Journal of the American Osteopatic Association. 2018 David Mantle and Iain Hargreaves. Coenzyme Q10 and Degenerative Disorders Affecting Longevity: An Overview. Antioxidants (Basel) Published online 2019 Feb Search for more information...
Comprehension Strategies for Reading Historical Fiction Phrase Elements My love is like a passages, some of the figurative language has been set in bolder type. Literary Terms 67 For example:. Close reading remains a or rhetorical figures, which--as the smallest distinguishable elements of a literary work "Robinson uses examples from). design elements, and written language. literary theorists to connote the uni- COMPREHENSION STRATEGIES FOR READING HISTORICAL FICTION PICTUREBOOKS 25/08/2018В В· How to Write a Literary Commentary. Start by reading the passage once out loud to yourself and once in your Examples of literary devices are metaphors, literary tools the author embeds the theme or meaning into separate elements that the reading such as noting a passage while reading. For example: design elements, and written language. literary theorists to connote the uni- COMPREHENSION STRATEGIES FOR READING HISTORICAL FICTION PICTUREBOOKS What literary devices with examples are in The Strange Discovering Evidence for a Literary Analysis Essay. literary elements below is a list of literary elements, or the parts of a story. when you examine and analyze your literary work for class presentation, ask the, tг¬m kiбєїm the reading passage is an example of which element of the story plot , the reading passage is an example of which element of the story plot tбєўi 123doc). Upper Elementary Lesson in Reading Literary Devices. get an answer for 'what is the difference between a literary and a also important are literary elements of //www.enotes.com/homework-help/what-some-examples, using the state curriculum: reading/ela, grade 8. explanation and/or examples of indicator a variety of self-selected and assigned literary texts including). Printable Reading Strategies Worksheets Help Teaching Close Reading of Literary Texts. When selecting a text or passage for close reading, (leaving knowledge and application of literary elements more or less 2nd Grade вЂ“Reading Standards for Literature 2nd Grade вЂ“Reading Standards for Literature " Where in the passage did you find that key are an example of
What Is a Noun? Defining a Noun - They come with articles. If it follows "a", "an", or "the" fairly closely, it’s probably a noun. If there’s an adjective in there, it’ll be between the article and the noun, so you’ll have to ask yourself, “Is this something I can feel, see, smell, taste or touch? Or does it describe something I can feel, see, smell, taste or touch?” If it’s the former, it’s a noun. If it’s the latter, it’s probably an adjective. - They are described by adjectives. If something is described as being blue, old, shiny, hot or wonderful (all adjectives), it’s probably a noun. - They act as subjects. Generally, the subject of a sentence is the thing that comes right before the verb. When you say, “The Dingo ate my baby”, the subject is “the Dingo”. It comes right before the verb (ate). Subjects are a little tricky because they can consist of just one word or a whole, long phrase that can contain several nouns. Gerund and infinitive verbs can also act as subjects of a sentence, but in that role, they are serving as nouns. Why? Because nouns act as subjects. - They act as objects and complements. Complements follow state-of-being verbs like “be”, “seem”, and “become”. Objects follow other verbs as well as prepositions. In the sentence, “Amy is a teacher”, the complement is “a teacher”. In the sentence, “Billy hit a teacher”, the object is “a teacher”. In the sentence, “I am sitting near a teacher”, the prepositional object is “a teacher”. In all cases, “teacher” is a noun. - They are names. All names of all things (people, cities, towns, counties, states, countries, buildings, monuments, rivers, mountains, lakes, oceans, streams, natural disasters, books, plays, magazines, articles, songs, works of art, etc.) are nouns. Not all nouns do all of these things all of the time, and not all the words that do some of these things are nouns, but by and large, if it looks like a noun and acts like a noun, it’s probably a noun. - Nouns whose singular forms end in s, z, x, ch, or sh need es to become plural (boss-bosses, box-boxes, watch-watches, bush-bushes). - Certain nouns that end in o also need es to become plural (potato-potatoes, hero-heroes, volcano-volcanoes). - For nouns that end in f or fe, change the “f” to a “v”, and add es (knife-knives, wolf-wolves). - If a singular noun ends in a single consonant followed by y, change the “y” to “i”, and add es (lady-ladies, spy-spies). Common vs. Proper Nouns Common nouns are not capitalized (unless they begin a sentence, of course), but proper nouns are always capitalized. Count vs. Non-Count Nouns Non-count (or non-countable/uncountable) nouns are those that we do not generally pluralize. Most liquids, powders and grains fall into this category. Even though there are many corn flakes in your bowl, you say you eat cereal for breakfast, not cereals. And you put sugar on it, not sugars, and you drink coffee with it, not coffees. We sometimes pluralize non-count nouns when we are referring to the container or form in which they come. You order two coffees (one for you, one for your friend), but what you really mean is two cups of coffee. You’re counting the cups, not the liquid. Concrete vs. Abstract Nouns A noun is any word that does one or more of these noun-y things. DU HỌC HOPECO 12 Hoa Phượng, Phường 2, Quận Phú Nhuận, Thành phố Hồ Chí Minh, Việt Nam ĐT: (08) 35 173 345 – 35 173 678 Fax: (08) 35 173 111
In our ever-expanding universe, light from distant galaxies takes longer to reach us and may someday escape our ability to see it entirely. After all, when we’re looking deep into space that’s millions of light years away, we’re seeing far into the past. What we observe today may have traveled beyond our ability to see it or no longer exist at all. That’s why it’s especially interesting when scientists discover parts of our distant universe that appear to be moving closer over time. That’s exactly what the astronomers who captured the latest image of the Messier 90 spiral galaxy (pictured above) uncovered through their observation. Hubble representatives provided a statement, as reported by LiveScience, that explains how astronomers measure light to calculate the movement of an entire galaxy that’s approximately 60 million light years away from our own: The galaxy is compressing the wavelength of its light as it moves towards us, like a slinky being squashed when you push on one end. On the visible light spectrum, shorter wavelengths appear blue. So, because its light is compressed from our perspective, Messier 90 exhibits a phenomenon called ‘blueshift,’ which indicates to scientists that Messier 90 is moving closer to us. Scientists measure the expansion of our universe by looking for the opposite: redshift. Based on the same principles, redshift indicates movement away. Despite the names of these terms, neither actually indicates a color of light but rather refers to human perception of the visible light spectrum. We perceive the longest visible wavelengths as red. While violet technically represents the shortest end of the spectrum, blueshift (or, alternatively, negative redshift) is nevertheless how we describe the compression of light frequency that indicates closer proximity. These terms represent our best approximation of color at such a great distance, but light frequencies change as they interact with various matter throughout the universe. Earth’s atmosphere, for example, acts as an opaque barrier to the vast majority of the electromagnetic spectrum while remains almost completely transparent to the sliver of that spectrum that we call visible light. The small amount of the visible spectrum Earth’s atmosphere absorbs gives us the appearance of a blue sky rather than a white one. When we look at images of distant galaxies they tend to look flat—just like anything else we look at from a significant distance—but the colors in images like that of the Messier 90 give us more than an aesthetic. Powerful telescope like Hubble use filters to capture monotone images of only specific frequency ranges of electromagnetic wavelengths. This not only helps understand the distance of light but provide a means of using color to represent that distance in the published images. Not every image of space uses color for the same purposes, but in context, the color in a captured image can tell you more about what you’re looking at. In this case, it’s about distance. The ability to capture multiple distance images can sometimes impose other restrictions, which is why the latest representation of Messier 90 looks like someone cut a staircase out of it. Powerful imaging systems can only capture so much with the desired amount of detail at a given time. Sometimes that results in some missing areas. Even with the ability to calculate the approximate movement of distant galaxies, we’re still left wondering why Messier 90 seems to grow closer when most of the universe essentially runs away from our vision. Scientists hypothesize that relates to the composition of the Virgo Cluster—a grouping of over 1,200 galaxies that include Messier 90. Virgo’s enormous mass appears to accelerate the movement of its galaxies into unusual orbits that send them closer and farther away from our perspective on Earth over time. Of course, with roughly 60 million light years between the Milky Way and Messier 90, we can only derive these conclusions from the visual data telescopes like Hubble can capture. We still require far more data to fully understand what’s actually happening so far beyond our reach. While we can capture beautiful images of far off galaxies and learn about their light, we’re only looking at the light that escapes and has changed throughout its travels. The evolution of telescopes and other imaging technology will allow us more precise measurements in the future and we may learn we’ve been looking at a picture that’s far less complete than we once thought. Nevertheless, it’s amazing to live in an era where we can regularly take a peak into the parts of our universe that live millions of lightyears away. Top image credit: ESA/Hubble & NASA, W. Sargent et al. - Astronomers Assemble the Most Detailed Picture of the Universe Ever - Hubble Will Use ‘Natural Telescopes’ To Find the Oldest Galaxies in the Universe - NASA May Have Fixed Hubble By Shaking It and Turning It Off and On

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