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August 11 is Cato Maximilian Guldberg’s birthday. Guldberg was a Norwegian chemist and mathematician who, with his brother-in-law, Peter Waage discovered the chemistry law of mass action.
The law of mass action relates the rate a chemical reaction progresses to the concentrations of the reactants. Up to this point, the rate of a reaction was thought to depend on the chemical affinity between the two reactants. For the reaction aA + bB → C, the reaction rate would be proportional to the concentrations of A and B and their stoichiometric ratios a and b. The proportionality constant between them is known as the rate constant, k.
reaction rate = k[A]a[B]b
When you think about it, a reaction is more likely to proceed quickly when there is more stuff to do the reaction.
The two weren’t immediately recognized for their discovery. The path to recognition involved a lesson in publishing in the language of who you want to gain recognition from. They published their new findings in a Norwegian scientific journal and consequently, the rest of the chemical world basically never heard of the work. The scientific community doesn’t often follow Norwegian journals. They republished their work in a French journal and the work remained obscure until German chemist, Wilhelm Ostwald published an article that mentioned the law and proved it with experiments of his own. When Dutch chemist Jacobus van’t Hoff derived his kinetics equations in 1888 and received credit for ‘discovering’ the relationship, they republished their original work in German. This time, they were recognized for being the original discoverers of mass action. German and English were the languages of chemistry in the 19th Century.
Another relationship Guldberg is known for came about from his investigations into how dissolved substances affect the freezing point and vapor pressure of the pure liquid. Guldberg discovered a relationship between boiling point and critical point of a liquid. The boiling point is the temperature where the vapor pressure of a liquid equal to the pressure surrounding the liquid and the liquid becomes a gas. The critical point is the temperature where there are no longer any phase boundaries. Guldberg showed the temperature of the boiling point is two-thirds the temperature of the critical point when measured on the absolute temperature scale. This relationship is known as Guldberg’s Rule.
Other Notable Science Events for August 11
1972 – Max Theiler died.
Theiler a South African/American virologist who was awarded the 1951 Nobel Prize in Medicine for his work on yellow fever. Theiler and Hugh Smith developed a vaccine for yellow fever just in time for an epidemic in West Africa. The Rockefeller Foundation distributed 28 million doses of this vaccine in 7 years that effectively eliminated the disease.
Theiler contracted yellow fever while pursuing his vaccine. Fortunately, he survived and gained the immunity surviving the disease grants.
1926 – Aaron Klug was born.
Klug is British chemist and biophysicist who was awarded the 1982 Nobel Prize in Chemistry for the development of crystallographic electron microscopy and discoveries into nucleic acid-protein complexes. Crystallographic electron microscopy uses the same principles of x-ray crystallography but uses electrons instead of x-rays to determine the structure. The process also takes two images from slightly different angles to create a stereo three-dimensional image.
1861 – James Bryan Herrick was born.
Herrick was an American physician that discovered the blood disease sickle-cell anemia. One of his patients came in with pain in his back and extremities with a slight fever and shortness of breath. After taking a blood sample he discovered several long sickle shaped red blood cells.
1858 – Christiaan Eijkman was born.
Eijkman was a Dutch physician who was awarded half the 1929 Nobel Prize in Medicine for the discovery of vitamins. He identified the disease beriberi is caused by poor diet and particular foods would prevent the disease.
It was later determined beriberi is caused by a vitamin B1 (thiamine) deficiency.
1854 – Macedonio Melloni died.
Melloni was an Italian physicist who was the first to investigate infrared radiation or radiant heat. He improved the design of the thermopile, which produces a current when heated to detect the radiant heat energy.
He created lenses of rock salt (rock salt is transparent to infrared light) to demonstrate this heat could be focused, reflected and polarized just like visible light. |
Braja Sorensen Team December 4, 2020 Worksheet
Math|english worksheets latest 2020 edition for grade 1 to 6 |ib |cbse |k12|subscribe today for special offer in 2020|online |download October 19, 2020 by admin.
Grade 6 math worksheets division. 5th grade math worksheets for division. 6th grade math division worksheets. We have a collection of free activities and worksheets that would help your students for grade 6 math preparation and practice.
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We do not claim ownership. This is a comprehensive collection of free printable math worksheets for sixth grade, organized by topics such as multiplication, division, exponents, place value, algebraic thinking, decimals, measurement units, ratio, percent, prime factorization, gcf, lcm, fractions, integers, and geometry. These our math printable worksheets for grade 6 have covered all major areas of grade 6 math, some of which include;
6th grade math worksheets, pdf printables to practice skills on math topics learnt in grade 6.these worksheets were created with teachers, homeschool parents and sixth graders in mind. In case you encounter a problem downloading a file, first, you can refresh the page or if needed you can restart your browser. Grade 2 math worksheets division.
21 posts related to grade 6 math worksheets division. These worksheets are pdf files. Free math worksheets for grade 6.
Download for free these sets of division worksheets for grade 3 to grade 6 learners and place value worksheets for grade 1 to grade 2 learners. Based on the math class 6 singaporean math curriculum, these math exercises are made for students in grade level 6.however, also students in other grade levels can benefit from doing these math worksheets. Multiplication and division math worksheets.
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Simply click on the download link to get your free and direct copy. There are also other downloadable materials below which we think will be very helpful to your kids. These division worksheets are a great resource for children in kindergarten, 1st grade, 2nd grade, 3rd grade, 4th grade, and 5th grade.
Grade 6 math worksheets division. |
A capillary tube is a very thin tube made of a rigid material, such as plastic or glass. The tubes are used to collect samples of liquids, which will flow up into the tubes against the effects of gravity in a process called capillary action. They are commonly used in medical and research fields to extract very small samples of liquids to be analyzed, such as blood samples for diabetics, or to transport them to other devices, such as Petri dishes or microscopes, for further study or experimentation.
The thickness in the opening of capillary tubes varies from application to application, with the determining factor being the density or weight of the fluids to be drawn in. There are many sizes of pre-manufactured tubes for use with specific applications, such as drawing blood to test for blood sugar levels. In research applications, researchers will often heat the center of a glass tube to near its melting point. They then pull the ends, stretching the center into a very fine tube suitable for their immediate needs and, once the glass cools, break it in the middle to create a custom tool.
All of these tubes function through a process called capillary action. This process uses two physical forces — surface tension and adhesion — to counter the effects of gravity and draw a sample up. Surface tension is the forming of a barrier at the surface of a fluid created by the force that it takes to separate individual molecules of the fluid from one another. This force can be observed in a drinking glass, which can be filled with water to a level slightly more than the volume of the glass, allowing it to rise above the rim. The water remains above the glass because the force required to separate the water molecules at the surface is greater than the force gravity is exerting on the water above the rim of the glass.
Adhesion aides in capillary action by creating a mutually attractive force between the liquid and the tube itself. In the example of a glass of water, water is attracted to, and adheres to, the rim of the glass, creating a boundary for the surface of the water. This is what keeps the water in the glass while the surface tension determines how high the water can rise above it.
Capillary tubes are, by nature, very thin. Because of this fact, there is a high amount of adhesion around the inside of the tube, which creates a surface area at the top and bottom of a liquid in the tube. As a result, when a liquid encounters one, it is drawn up into the tube by the forces of adhesion, creating a surface with a specific surface tension that remains intact due to the adhesion of the sides of the tube. The liquid will continue to rise up the tube until the weight of total mass of all the liquid in the tube exceeds the surface tension at the bottom. |
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- What Is BMI?
- How Is BMI Calculated for Kids?
- BMI-for-age and Growth chart for girls :
- BMI-for-age and Growth chart for boys :
- How to Track your Child’s BMI?
- What is BMI Percentile and How Should It Be Interpreted?
- What Is Normal BMI for Children?
- How Is BMI Used for Kids?
- Is Bmi Interpreted the Same Way for Children As It Is for Adults?
- Weight Categories for Kids
- Health Risks of Having a High and Low BMI Percentile
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Obesity is a growing cause of concern for parents all over the world today. A healthy weight during childhood is needed for healthy functioning of the heart and for the prevention of any cardiovascular diseases. Heart disease is not the only risk related to obesity. Obesity can also cause other lifestyle illnesses like Type 2 diabetes, asthma, sleep apnea, and psychological problems owing to the social stigma of appearance.
What Is BMI?
Body Mass Index (BMI) is the weight of the person in kilograms divided by the square of the height measured in metres. For children and teenagers, BMI is age and gender-specific and referred to as BMI-for-age. Being overweight and underweight during childhood can pose a risk and can lead to health issues.
How Is BMI Calculated for Kids?
Body Mass Index is a calculation of a child’s weight in relation to their height to assess body fat and diagnose any potential weight-related issues. Calculating the BMI for children involves tracking the BMI to other children of the same gender and age in charts to present a detailed picture over a period of time. A smooth curve reflects healthy growth. Track the progress but make sure to consult your doctor to take regular BMI measurements. Once you finish calculating, use the BMI chart for children to track the progress.
BMI-for-age and Growth chart for girls :
BMI-for-age and Growth chart for boys :
How to Track your Child’s BMI?
Your doctor will determine routine BMI check-ups starting from when your child is 2 years old. These measurements will be plotted on a chart to compare them with kids of the same sex and age. Doctors plot BMIs of kids on standard growth charts, separate ones for boys and girls. This helps to account for differences in growth rates and the amount of body fat as age matures.
The information recorded on your child’s medical record will be monitored and tracked to see the progress over several visits. This information helps to identify kids and adolescents at risk of being overweight as they grow older. By closely monitoring these kids, doctors can take the required action needed to prevent any issues that may arise in future.
What is BMI Percentile and How Should It Be Interpreted?
BMI calculated for children and teens is expressed as a percentile, plotted on the growth charts to obtain a percentile ranking. Percentiles are commonly used as an indicator to assess the size and growth patterns of children. The percentile is a comparative yardstick to other kids of the same age and sex. Weight and height change during growth and development so does their relation to body fat.
What Is Normal BMI for Children?
BMI numbers for different ages and genders have different interpretations. A comparison with other children is mandatory as children develop muscles with age and boys tend to have more muscle than girls. A healthy BMI for children in percentile lies between the 5th percentile and the 85th percentile. Normal child BMI range for boy’s ranges from 13.8-16.8 for a 5-year-old, 14.2-19.4 for a 10-year-old and 6.5-23.4 for a 15-year-old. Normal BMI range for girls ranges from 13.6-16.7 for a 5-year-old, 14-19.5 for a 10-year-old and 16.3-24 for a 15-year-old.
How Is BMI Used for Kids?
BMI is not a diagnostic tool for kids but a screening measure for any weight-related issues. If a child’s graph indicates a high BMI, doctors will recommend further direct measure like skinfold thickness measurements, diet evaluations and other health screening to determine if excess fat is a problem.
Is Bmi Interpreted the Same Way for Children As It Is for Adults?
Although BMI is calculated on the basis of weight and height, and their relation to body fat, it needs to be expressed in relation to other children of the same sex and age. With children, it needs to be done on a comparative basis as children develop and mature with age. For adults, BMI is interpreted as weight status categories which are independent of sex and age.
Weight Categories for Kids
As soon as a child’s BMI is ascertained, it can be seen where it falls within the expected range. The weight categories are mentioned below:
- Underweight – A category where the BMI is less than the 5th percentile.
- Normal Weight – A category where the BMI is between the 5th percentiles to the 85th percentile.
- Over Weight – A category where the BMI is more than the 85th percentile to below the 95th percentile.
- Obese – A category where the BMI is greater than or equal to the 95th percentile.
Health Risks of Having a High and Low BMI Percentile
- High blood pressure
- High Cholesterol
- Type 2 diabetes
- Sleep apnea and asthma
- Liver diseases
- Problems in joints and muscles
- Stress, depression and other behavioural problems owing to low self-esteem
Risks associated with being underweight:
- Respiratory disorders
- Weak Immune system
- Prone to injuries
- Nutritional deficiencies
BMI cannot be used to diagnose a health issue but is an effective screening tool to delve deeper to probe any underlying issues. It provides a glimpse to determine any weight-related issues that a child may have or could be prone to in the future. |
A distant galaxy more massive than our Milky Way - with more than a trillion stars - has revealed that the 'cores' of massive galaxies in the Universe had formed already 1.5 billion years after the Big Bang, about 1 billion years earlier than previous measurements revealed.
Researchers published their analysis on November 6, 2019 in The Astrophysical Journal Letters, a journal of the American Astronomical Society.
"If we point a telescope to the sky and take a deep image, we can see so many galaxies out there," said Masayuki Tanaka, paper author and associate professor of astronomical science in the Graduate University for Advanced Studies and the National Astronomical Observatory of Japan. "But our understanding of how these galaxies form and grow is still quite limited -- especially when it comes to massive galaxies."
Galaxies are broadly categorized as dead or alive: dead galaxies are no longer forming stars, while living galaxies are still bright with star formation activity. A 'quenching' galaxy is a galaxy in the process of dying -- meaning its star formation is significantly suppressed. Quenching galaxies are not as bright as fully alive galaxies, but they're not as dark as dead galaxies. Researchers use this spectrum of brightness as the first line of identification when observing the Universe.
The researchers used the telescopes at the W.M. Keck Observatory in Hawaii to observe a quenching galaxy in what is called the Subaru/XMM-Newton Deep Field. This region of the sky has been closely observed by several telescopes, producing a wealth of data for scientists to study. Tanaka and his team used an instrument called MOSFIRE on the Keck I telescope to obtain measurements of the galaxy. They obtained a two-micron measurement in the near-infrared spectrum, which the human eye cannot see, but it confirmed that the light from the galaxy was emitted just 1.5 billion years after the Big Bang. The team also confirmed that the galaxy's star formation was suppressed.
"The suppressed star formation tells you that a galaxy is dying, sadly, but that is exactly the kind of galaxy we want to study in detail to understand why quenching occurs," said Francesco Valentino, a co-author of the paper and an assistant professor at the Cosmic Dawn Center in Copenhagen.
According to Valentino, astronomers believe that massive galaxies are the first to die in the history of the Universe and that they hold the key to understanding why quenching occurs in the first place.
"We also found that the 'cores' of massive galaxies today seem to be fully formed in the early Universe," Tanaka said. How stars move within a galaxy depends on how much mass that object contains. Tanaka and his team found that the stars in the distant galaxy seem to move just as quickly as those closer to home. "The previous measurement of this kind was made when the Universe was 2.5 billion years old. We pushed the record up to 1.5 billion years and found, to our surprise, that the core was already pretty mature."
The researchers are continuing to investigate how massive galaxies form and how they die in the early Universe, and they are searching for more massive quenching galaxies in the far distant Universe that may shed light on earlier phases of the process.
"When did the first dead galaxy appear in the Universe?" Tanaka asked. "This is a very interesting question for us to address. To do so, we will continue to observe the deep sky with the largest telescopes and expand our search as more advanced facilities become available."
Funders: Japan Society for the Promotion of Science, the Danish National Research Foundation, the Carlsberg Foundation, the European Research Council, the Japanese Cabinet Office, the Ministry of Education, Culture, Sports, Science and Technology-Japan, the Toray Science Foundation, the National Astronomical Observatory of Japan, the Kavli Institute for the Physics and Mathematics of the Universe, the High Energy Accelerator Research Organization, Academia Sinica Institute of Astronomy and Astrophysics, Princeton University
The Astrophysical Journal Letters |
Horn Corals are from the extinct order of corals called Rugosa. Rugose means wrinkled. The outside of these corals have a wrinkled appearance. Horn Coral grows in a long cone shape like a bull’s horn. The fossil is the skeleton of the coral animal or polyp. They built these cone shaped structures from calcium carbonate that came from the ocean water. The animal lived at the top of the cone. As the animal got bigger it added more material to the cone. Each layer was a little bigger than the previous one.
All corals belong to the phylum of animals called cnidaria. They are related to jellyfish which are also cnidaria.
While modern corals are colonial the now extinct horn corals could be colonial or solitary animals.
They had many tentacles sticking out to gather food. The tentacles gave them a flower like appearance.
The oldest of the Rugosa corals are found in rocks from the Ordovician Period. Many species evolved during the Paleozoic Era. As a group they flourished until the Permian Period when they became extinct along with most living things during the Great Permian Extinction.
Geologic Time Geologic Time LineProterozoic Era |
08 January 2009 by Andy Coghlan
Stem cells, we all know what they are and if we don’t well here is a brief introduction. Stem cells which are found in multicellular organisms, divide and separate into a diverse range of specialized cells, they can self – renew themselves and produce more cells in the process. Similar to a starfish. They are widely used in medicine. Patients who are usually treated by stem cells get them from a donor, but new research has shown that specific drugs when injected into the body can release very specific stem cells from the bone marrow. This discovery has lead to many patients being treated faster and being able to heal quicker, as the body itself would produce the same stem cells needed to repair broken bones, ligaments and even cardiac tissue. Since the body usually rejects any foreign objects , the stem cells would work perfectly because it is being produced by the body itself. Using this method can also over come ethical objections.
Sara Rankin of Imperial college London , is a member of the team that discovered this method, she describes it as promoting self – healing. Stem cells have been recorded to develop into new erythrocytes , but never before have they been able to regenerate new tissue and this leads to a wider range of treatment.
Started with two types of cells.
In order for Rankin and her team to test this method, they first needed a test that had been used previously, because as stated before stem cells were known to grow into new erythrocytes. So using test mice they administered a natural growth factor which lasted for four days, after the drug Mozobil was injected and this released the cells that were located in the bone marrow into the bloodstream. Granulocyte colony stimulating factor (GCSF) was then administered to the mice followed by Mozobil. Now this procedure isn’t a new one as it was already used in patients who underwent treatment for lymphoma. Bascially what the drug did when paired wit the factor was produce more blood stem cells, so much more that the new blood cells can replace those that were lost due to the cancer.
Now the real test was to see if when paired with other factors if the drug would have the same effect. And fortunately it did, the procedure worked out on behalf of two different types of stem cells. When the drug was preceded by the vascular endothelial growth factor ( VEGF) the two types of stem cells that came into play were:
Mesenchymal stem cells (MSCs) which regenerates bone and tissues
Epithelial progenitor cells ( EPCs) which can stimulate the growth and repair of blood vessels.
Even though this has been a huge break through, sometimes things always don’t go the way you planned. While the procedures worked well individually they don’t like working together so the production of one type of cell can block the production of another type of cell. For example GCSF-based treatment blocks the production of MSCs for tissue repair. Even though this was unfortunate it isn’t the end , as with any thing that is worth it in life it would not be easy to achieve and further research with different factors can produce different results. Who knows what the bone marrow entails, only time will tell.
Just this one research project has lighted some sparks in the eyes of fellow scientists. Robert Lanza, chief scientists at Advanced Cell Technology in Worcester Massachusettes even proposed an idea that the stem cells can be used to grow new organs, and by using the Mozobil drug stimulate the grow of blood vessels, which would provide the newly formed organ with a blood supply.
This has been the end of my second published paper review I do hope that you found it to be interesting and very informative, even inspiring as fellow scientists in the making. Please show your appreciation by clicking the like button! Thank you 😀 |
Antarctica is the coldest, most desolate place on Earth, and the Southern Ocean that surrounds it is much the same...with one pretty massive exception. The hydrothermal vents on the ocean floor are hot, dark oases, full of previously unknown species.
The East Scotia Ridge is located right at the bottom of the Southern Ocean, and it's home to tons of thermal vents, including the super-hot black smokers that can reach well over 700 degrees Fahrenheit. Though almost no sunlight reaches the areas around these vents, the vents are constantly spewing out heat and a particular brew of chemicals that can sustain some very specifically adapted organisms.
And it isn't just tiny plankton or bacteria-like organisms that eke out an existence around these vents. The bottom of the Southern Ocean is home to completely new species of crab, starfish, barnacles, sea anemones and maybe even an octopus, all of them evolved to live off the heat and chemicals of the vents. Research leader Alex Rogers of Oxford explains how these creatures survive:
"Hydrothermal vents are home to animals found nowhere else on the planet that get their energy not from the Sun but from breaking down chemicals, such as hydrogen sulphide. The first survey of these particular vents, in the Southern Ocean near Antarctica, has revealed a hot, dark, 'lost world' in which whole communities of previously unknown marine organisms thrive."
The Antarctic vents seem to be dominated by this new crab species, a type of yeti crab. Huge colonies of this crustacean surround all the vents of the Southern Ocean, as you can see in the image on the left. The survey team's craft, the rather aptly named Remotely Operated Vehicle (ROV), also saw a predatory starfish with seven arms crawling across a field of barnacles - as you might guess, we've never seen anything like that before. There was also a glimpse of a mysterious pale octopus on the seafloor, which might well be the representative of a new species.
The vent ecosystems of the Southern Ocean are almost nothing like the vents found in the Pacific, Atlantic, and Indian Oceans. Those other, previously explored vents are full of tubeworms, vent mussels, vent crabs, and vent shrimps, and none of those species had any presence at all in the waters around Antarctica. That suggests the Southern Ocean represents a sort of boundary line between different vent systems. Even more excitingly, it suggests thermal vents are capable of far more biological diversity and complexity than we had previously imagined possible.
Via PLoS Biology. Images courtesy of Oxford University. |
Let’s all put on our science-fiction hats and imagine that humans get wiped off the face of the Earth tomorrow. Perhaps a mysterious superbug kills us all overnight, or maybe we organize a mass migration to live on the moon. In a matter of a day, we’re gone without a trace.
If your first response to this scenario is “What would happen to the climate now that fossil fuel burning has stopped?” then you may be afflicted with Climate Science. (I find myself reacting like this all the time now. I can’t watch The Lord of the Rings without imagining how one would model the climate of Middle Earth.)
A handful of researchers, particularly in Canada, recently became so interested in this question that they started modelling it. Their motive was more than just morbid fascination – in fact, the global temperature change that occurs in such a scenario is a very useful metric. It represents the amount of warming that we’ve already guaranteed, and a lower bound for the amount of warming we can expect.
Initial results were hopeful. Damon Matthews and Andrew Weaver ran the experiment on the UVic ESCM and published the results. In their simulations, global average temperature stabilized almost immediately after CO2 emissions dropped to zero, and stayed approximately constant for centuries. The climate didn’t recover from the changes we inflicted, but at least it didn’t get any worse. The “zero-emissions commitment” was more or less nothing. See the dark blue line in the graph below:
However, this experiment didn’t take anthropogenic impacts other than CO2 into account. In particular, the impacts of sulfate aerosols and additional (non-CO2) greenhouse gases currently cancel out, so it was assumed that they would keep cancelling and could therefore be ignored.
But is this a safe assumption? Sulfate aerosols have a very short atmospheric lifetime – as soon as it rains, they wash right out. Non-CO2 greenhouse gases last much longer (although, in most cases, not as long as CO2). Consequently, you would expect a transition period in which the cooling influence of aerosols had disappeared but the warming influence of additional greenhouse gases was still present. The two forcings would no longer cancel, and the net effect would be one of warming.
Damon Matthews recently repeated his experiment, this time with Kirsten Zickfeld, and took aerosols and additional greenhouse gases into account. The long-term picture was still the same – global temperature remaining at present-day levels for centuries – but the short-term response was different. For about the first decade after human influences disappeared, the temperature rose very quickly (as aerosols were eliminated from the atmosphere) but then dropped back down (as additional greenhouse gases were eliminated). This transition period wouldn’t be fun, but at least it would be short. See the light blue line in the graph below:
We’re still making an implicit assumption, though. By looking at the graphs of constant global average temperature and saying “Look, the problem doesn’t get any worse!”, we’re assuming that regional temperatures are also constant for every area on the planet. In fact, half of the world could be warming rapidly and the other half could be cooling rapidly, a bad scenario indeed. From a single global metric, you can’t just tell.
A team of researchers led by Nathan Gillett recently modelled regional changes to a sudden cessation of CO2 emissions (other gases were ignored). They used a more complex climate model from Environment Canada, which is better for regional projections than the UVic ESCM.
The results were disturbing: even though the average global temperature stayed basically constant after CO2 emissions (following the A2 scenario) disappeared in 2100, regional temperatures continued to change. Most of the world cooled slightly, but Antarctica and the surrounding ocean warmed significantly. By the year 3000, the coasts of Antarctica were 9°C above preindustrial temperatures. This might easily be enough for the West Antarctic Ice Sheet to collapse.
Why didn’t this continued warming happen in the Arctic? Remember that the Arctic is an ocean surrounded by land, and temperatures over land change relatively quickly in response to a radiative forcing. Furthermore, the Arctic Ocean is small enough that it’s heavily influenced by temperatures on the land around it. In this simulation, the Arctic sea ice actually recovered.
On the other hand, Antarctica is land surrounded by a large ocean that mixes heat particularly well. As a result, it has an extraordinarily high heat capacity, and takes a very long time to fully respond to changes in temperature. So, even by the year 3000, it was still reacting to the radiative forcing of the 21st century. The warming ocean surrounded the land and caused it to warm as well.
As a result of the cooling Arctic and warming Antarctic, the Intertropical Convergence Zone (an important wind current) shifted southward in the simulation. As a result, precipitation over North Africa continued to decrease – a situation that was already bad by 2100. Counterintuitively, even though global warming had ceased, some of the impacts of warming continued to worsen.
These experiments, assuming an overnight apocalypse, are purely hypothetical. By definition, we’ll never be able to test their accuracy in the real world. However, as a lower bound for the expected impacts of our actions, the results are sobering. |
ESA, the European Space Agency, has launched a mission in December 2013 that turns out to be a huge source of new data for astronomers. Where NASA’s Hubble Space Telescope has already proven its worth as a useful source of new knowledge, its European counterpart seems to do the exact same thing. In fact, Gaia has created the richest star map of our Milky Way galaxy until now, and it goes even further!
In the end of 2013, ESA launches Gaia into the Earth’s orbit with high expectations. After orbiting and gathering information, observations stars positions and its motions for 22 months, the first publication came out in 2016 and it showed some promising results; an unprecedented amount of data. The information released in this publication showed the distances and motions of more than a billion stars, 1.692.919.135 to be precise! But it did much more than that. It defined the color of 1.38 billion stars, the speed at which 7 million stars are moving away or towards us, and it measured the surface temperature of 161 million stars. While it was at it, Gaia also determined the position of 14.000 objects (mainly planetoids) in our own solar system.
Gaia is a unique satellite
Günther Hasinger, the Director of Science of ESA says: “The observations collected by Gaia are redefining the foundations of astronomy. Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data. It demonstrates the need for long-term projects to guarantee progress in space science and technology and to implement even more daring scientific missions of the coming decades."
The movement of stars that are so far away is very difficult to determine. Since it means that any movement is hardly noticeable.In order for Gaia to measure all these things, it had to be equipped with very sensitive instruments. And with very sensitive, we mean very sensitive. Gaia would be able to measure the growth of a human hair located on the Moon.
Gaia creates work for years
With these huge amount of newly available data, astronomers think they will have enough to work with for the next few years. Already, scientists are using it to make their own observations. Amini Helmi, for example, noticed that spherical clusters of stars around the Milky Way move in groups. Antonella Vallenari is focusing more on the brightness of stars: “”We have built the most detailed Hertzsprung-Russell diagram of stars ever made on the full sky and we can already spot some interesting trends. It feels like we are inaugurating a new era of Galactic archaeology.”
And that is the beauty of Gaia’s work. Astronomers get to create new ways of conducting science, discover things we still know nothing about. Although the first set of data was released in 2016, for the next years to come, we can expect a numerous amount of astronomical discoveries and publications all made possible thanks to the incredible load of information Gaia has provided us. |
- This lesson is geared towards beginning English language learners who plan to take a U.S. driving test. The goal of this lesson is for learners to be able to identify various traffic and/or road signs and describe their meanings for the purpose of passing a U.S. driving test and driving safely on the road.
- Remix of:
- Describing Traffic and Road Signs in Basic English
- Career and Technical Education, English Language Arts
- Career / Technical, Adult Education
- Material Type:
- Diagram/Illustration, Homework/Assignment, Interactive, Lesson Plan
- Melissa Rios
- Date Added:
- Creative Commons Attribution 4.0
- Media Format:
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Life is not easy for the trees in a forest: To avoid being edged out by other trees, they must prevail in the struggle for resources. Ultimately, the successful trees are those whose traits are best suited to their location. An international team, which included researchers from the Max Planck Institute for Biogeochemistry in Jena, has now discovered how three characteristic traits – wood density, maximum height and specific leaf area – decide which trees will emerge victorious in the competition between neighbouring individuals.
Surprisingly, these correlations are consistently applicable throughout the world. Moreover, it emerged from the study that the competition between trees of the same species is always more intensive than that between trees of different species.
Trees in forests all over the world compete with each other for survival – this also applies to the southern beeches in the temperate rainforest of Mount Aspiring National Park in New Zealand shown here. To prevail in the competition, an individual tree must possess a suitable combination of traits and, if possible, be clearly different from its neighbors. (© MPI for Biogeochemistry, A. Günther)
Almost one-third of the Earth’s land surface – from the polar circles to the tropics – is under forest cover. The forests accommodate an astonishing variety of tree species with equally wide-ranging forms and strategies. In the tropics alone, mixtures comprising up to 53,000 different tree species are found in the same ecosystems.
Ecologists have long been seeking a general approach that would enable them to predict which of the tens of thousands of tree species that exist in the world can grow next to each other, which ones compete with each other and which will prevail in the competition for survival. This depends on how well individual trees grow and, ultimately, which species can stand their ground in the forest.
Species with greater wood density can well tolerate their neighbours
“Foresters have known for centuries which tree species dominate in their forests,” says Jens Kattge, a Research Group Leader at the Max Planck Institute for Biogeochemistry. “For a long time it was assumed that tree species should be as mixed as possible so that they can occupy many ecological niches and co-exist side-by-side in a location.” In a study headed by George Kunstler from the French National Research Institute of Science and Technology for Environment and Agriculture (IRSTEA) in Grenoble, scientists from all over the world have now systematically examined whether the competition between the trees is subject to certain rules, whether these rules apply consistently at global level and what form they take. Given the incalculable number of tree species that exist, this was clearly an enormous task.
In a study currently published in Nature, rather than focusing on taxonomic species as was the standard approach adopted up to now, the researchers identified such globally valid rules by comparing the functional traits of the species with each other. In an analysis of all of the Earth’s forest ecosystems, the researchers discovered how the competition between the trees is affected by three traits: wood density, specific leaf area and maximum height. These traits were examined in detail in the study. It was already known that they have a similar influence on the physiological functions of individual plants all over the world. “It now emerges that these traits also determine the competition between neighbouring trees on a global level,” says Jens Kattge. “Given the vast differences in the environmental conditions found in the world’s forests, this is astonishing.”
Thus, according to the study, it is not only important that the trees in a location are as diverse as possible so that they can survive alongside each other, they must also differ from each other in respect of one or more of the three traits. These traits also provide a good indication of which species are most resilient to competition. For example, species with a high wood density appear to be particularly tolerant to their competing neighbours and this enables them to prevail in the long term. In contrast, trees with lower wood density grow faster, and for this reason lead the field in the early stages of the competition at least, when trees colonize new area.
Competitive pressure is greatest between trees of the same species
However, a tree must not outperform its neighbours in relation to all traits to be a successful competitor. For example, the native beech tends to grow rather slowly and does not reach a particularly impressive height; it has, however, a high wood density and shade-tolerance, which gives it a major advantage in the ecological competition during the second phase of forest colonization after around 50-100 years. With its traits, it comes very close to a combination identified by the study as being very successful in the long-term competition for survival in global forests. Therefore, from a long-term perspective, shade-tolerant high-growing trees with medium to high wood density enjoy competitive advantages all over the world.
It also emerged from the study that the competitive pressure within one and the same species is always greater than that between trees of different species. This is also rather obvious, as trees from the same species have more or less identical traits. They thus occupy the same ecological niche and compete for the same resources in a location. The fact that one of two trees will ultimately prevail is above all due to the fact that even trees of the same species will not have identical locations and traits. Experts refer here to intra-species variability, which can have advantages for individual trees when it comes to obtaining the resources they need.
Furthermore, the fact that the role played by chance in the ecological competition is far from insignificant, should not be forgotten here – irrespective of whether the competitors are from the same species or not. For example, plants can be damaged by disease or wild animals and this impairs their chances of survival in the battle with their competitors.
More accurate climate forecasting thanks to more detailed vegetation models
For this study on competition in forests, almost 40 scientists from all over the world collated the results of national forest inventories and monitoring data from test sites containing a total of three million trees representing over 2,500 species from over 140,000 locations. The data were evaluated by researchers from Macquarie University in Sidney, Australia. The global plant trait database TRY, which is operated at the Max Planck Institute for Biogeochemistry in Jena and to which the German Centre for Integrative Biodiversity Research (iDiv) also contributes, made a crucial contribution to the study.
The new findings of the study highlight the fact that the competition for resources can be largely explained by a few functional traits. The comparison of functional traits can also provide information about which tree species can survive together in a location. Based on this study, for example, forest managers can improve their planning of tree species mixtures. Given the need to estimate the impacts of climate change on forest ecosystems and vice versa, there is a greater demand now for predictions regarding the composition of plant communities and the competition between the species they contain. The study’s findings can be incorporated into vegetation models and therefore also in Earth system models which take the influence of climate on vegetation into account and vice versa. In this way, they can contribute to improving the forecasting of changes in the climate over the next century. |
organisms). Children’s life experiences of learning about what different living things “eat” creates a common perception of eating as an
active process (this eats that). This view confounds their reading of
the diagram because the arrows have a different (conventional) meaning than their expectations.
Example 2: Arrow Meaning
RESEARCHER: Have a look at this diagram for me. What do you think is
MICK: Well, ah, so the bird is eating the frog, the frog is eating the snail
and the butterfly, and the snail and butterfly is eating the plant.
RESEARCHER: Okay, and what do the arrows mean?
MICK: Well when you, what it eats is that.
In direct contrast to Norma, Mick started reading from the opposite
end of the diagram, at the bird. The presence and direction of the
arrows did not affect his reading approach. Mick invented his
own definition of arrow meaning, “what it eats is that,” to compensate for the arrows facing the opposite direction. An underlying
intuition that “the biggest animal is most important” likely influenced Mick’s choice of starting point in reading the diagram.
Example 3: Reading Pathway
RESEARCHER: Can you tell me what is happening in this diagram please?
ELAINE: The pot plant [pause] the snail, the pot plant. The snail would
come to the pot plant. The butterfly would come to the pot
plant. The snail will eat a bit of the pot plant and the butterfly
will eat a bit of the pot plant. Then the frog will eat the butterfly and the snail, and the kookaburra will eat the frog.
RESEARCHER: What do you the arrows mean in this diagram?
ELAINE: Going on.
RESEARCHER: Anything else?
ELAINE: [Shakes head]
Elaine was unsure whether to start reading from the plant or the snail.
It took her a while to figure out that the diagram was concerned with
feeding relationships. Her convoluted reading approach is shown in
Elaine made sense of the diagram by choosing a nonstandard
starting point and adopting a unique, backward-looping strategy
to read the arrows from right to left rather than left to right. When
asked directly about arrows, her generic meaning “going on”
indicated lack of knowledge of specific scientific meaning. In the study
students were re-interviewed after a one-month period to determine any lasting effects of diagram interaction. Elaine’s reading
approach the second time is shown in Figure 5.
This time Elaine’s diagram reading was more succinct, aided by
a direct approach that was more ordered. She commenced with the
herbivores and again mentally reversed the arrows, but maintained
a consistent approach to the diagram. This highlights the value of
repeated exposure with biology diagrams to hone students’ reading
skills. As students become more comfortable with the visual representations and rethink their meaning, the messages they are
designed to convey become clearer.
Example 4: Accumulation Effect
RESEARCHER: What’s happening in this picture?
MITCHELL: The kookaburra eats a frog and it eats butterfly, whatever,
or moth and snails eats plants, and butterflies eat plants,
and frogs eats snails, and the kookaburra eats all of them.
RESEARCHER: Good, and what does the arrow mean?
MITCHELL: Means eats.
RESEARCHER: So the plant eats the snail?
MITCHELL: No, the snail eats the plant.
Mitchell started reading the food web at the bird. Like others he
overcame the problem of arrow meaning by reading the diagram
in the reverse direction. He read toward the left, correctly identifying what each animal “eats” before incorrectly stating that the kookaburra “eats all of them,” suggesting they were all consumed by the
bird. Mitchell appears to have an intuitive view that “large animals
eat everything else,” which influenced this interpretation of the food
web. This example highlights that the arrows have multiple functions
Figure 4. Elaine’s diagram reading path. |
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 February 4
Explanation: Why does this crater on Mercury look like a spider? When the robotic MESSENGER spacecraft glided by the planet Mercury last month, it was able to image portions of the Sun's closest planet that had never been seen before. When imaging the center of Mercury's extremely large Caloris Basin, MESSENGER found a crater, pictured above, with a set of unusual rays emanating out from its center. A crater with such troughs has never been seen before anywhere in our Solar System. What isn't clear is the relation of the crater to the radial troughs. Perhaps the crater created the radial rays, or perhaps the two features appear only by a chance superposition -- the topic is sure to be one of future research. MESSENGER is scheduled to fly past Mercury twice more before firing its thrusters to enter orbit in 2011.
Authors & editors:
Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
A service of: ASD at NASA / GSFC
& Michigan Tech. U. |
Small changes in timing of breeding among subarctic passerines over a 32-year period
- BECC - Biodiversity and Ecosystem services in a Changing Climate
Many bird populations in temperate regions have advanced their timing of breeding in response to a warming climate in recent decades. However, long-term trends in temperature differ geographically and between seasons, and so do responses of local breeding populations. Data on breeding bird phenology from subarctic and arctic passerine populations are scarce, and relatively little data has been recorded in open-nesting species. We investigated the timing of breeding and its relationship to spring temperature of 14 mainly open-nesting passerine species in subarctic Swedish Lapland over a period of 32 years (1984–2015). We estimated timing of breeding from the progress of post-juvenile moult in mist-netted birds, a new method exploring the fact that the progress of post-juvenile moult correlates with age. Although there was a numerical tendency for earlier breeding in most species (on average −0.09 days/year), changes were statistically significant in only three species (by −0.16 to −0.23 days/year). These figures are relatively low compared with what has been found in other long-term studies but are similar to a few other studies in subarctic areas. Generally, annual hatching dates were negatively correlated with mean temperature in May. This correlation was stronger in long-distance than in short-distance migrants. Although annual temperatures at high northern latitudes have increased over recent decades, there was no long-term increase in mean temperature in May over the study period at this subarctic site. This is probably the main reason why there were only small long-term changes in hatching dates.
- climate change
- hatching date
- long-term study
- post-juvenile moult
- ISSN: 0019-1019 |
Today’s border with Mexico is the product of invasion and war. Grasping some of the motives for that war and some of its immediate effects begins to provide students the kind of historical context that is crucial for thinking intelligently about the line that separates the United States and Mexico. It also gives students insights into the justifications for and costs of war today.
This activity introduces students to a number of the individuals and themes they will encounter in the chapter from Howard Zinn’s A People’s History of the United States, “We Take Nothing by Conquest, Thank God.” The individual roles include:
- Cochise, Chiricahua Apache leader
- Colonel Ethan Allen Hitchcock, commander of the 3rd Infantry Regiment
- Congressman Abraham Lincoln, Whig Party, Illinois
- Doña Francesca Vallejo
- Francisco Márquez, Mexican Cadet
- Frederick Douglass
- General Mariano Vallejo
- General Stephen Kearny
- Henry David Thoreau
- Jefferson Davis, plantation owner, Mississippi
- María Josefa Martínez, Santa Fe, New Mexico
- Padre Antonio José Martínez
- President James K. Polk
- Reverend Theodore Parker
- Sgt. John Riley San Patricio Battalion, Formerly U.S. Army
- William Lloyd Garrison , Founder, American Anti-Slavery Society and
- Wotoki, Miwok Indian, California.
The lesson includes a reading from Zinn’s chapter, “We Take Nothing by Conquest, Thank God.” Here is an excerpt.
Frederick Douglass wrote in his Rochester newspaper the North Star, January 21, 1848, of “the present disgraceful, cruel, and iniquitous war with our sister republic. Mexico seems a doomed victim to Anglo Saxon cupidity and love of dominion.” Douglass was scornful of the unwillingness of opponents of the war to take real action (even the abolitionists kept paying their taxes):
No politician of any considerable distinction or eminence seems willing to hazard his popularity with his party … by an open and unqualified disapprobation of the war. None seem willing to take their stand for peace at all risks; and all seem willing that the war should be carried on, in some form or other.
Where was popular opinion? It is hard to say. After the first rush, enlistments began to dwindle. Historians of the Mexican war have talked easily about “the people” and “public opinion.” Their evidence, however, is not from “the people” but from the newspapers, claiming to be the voice of the people. The New York Herald wrote in August 1845: “The multitude cry aloud for war.” The New York Morning News said “young and ardent spirits that throng the cities … want but a direction to their restless energies, and their attention is already fixed on Mexico.”
It is impossible to know the extent of popular support of the war. But there is evidence that many organized workingmen opposed the war. There were demonstrations of Irish workers in New York, Boston, and Lowell against the annexation of Texas. In May, when the war against Mexico began, New York workingmen called a meeting to oppose the war, and many Irish workers came. The meeting called the war a plot by slave owners and asked for the withdrawal of American troops from disputed territory. That year, a convention of the New England Workingmen’s Association condemned the war and announced they would “not take up arms to sustain the Southern slaveholder in robbing one-fifth of our countrymen of their labor.
This lesson was published by Rethinking Schools in The Line Between Us: Teaching About the Border and Mexican Immigration. For more teaching activities like “U.S. Mexico War: “We Take Nothing by Conquest, Thank God,” order The Line Between Us with role plays, stories, poetry, improvisations, simulations and video edited by Bill Bigelow.
See Table of Contents.
I teach at an inner city school, an incredibly diverse school. The lesson on the Mexican American War and the role play are incredibly effective in helping students understand the role of racial bias in the history of U.S. Foreign Policy.
Students really appreciate the opportunity to read and reflect on Zinn’s chapter, and appreciate different points of view about the war during the role play. My Latino students appreciate the approach, one that all too often in their education has not received the attention it deserves. This lesson took on new forms and even greater importance at our school, with the organization of a Hispanic Union, and it informed our celebration of Hispanic Heritage Month and current events, like the debate on immigration policy.
Many of my 12th grade students today in Government class still look back to this lesson as a foundational moment in their learning about the history of US/Mexico relations. (They) see that the border issue today has a much longer history and wider context than they originally may have realized.
I dedicate a unit to westward expansion, and using the U.S.-Mexico War Tea Party activity has given students many perspectives on the war.
They enjoy this lesson in particular because they are able to interact with one another and teach in turn their assigned perspectives. I find that they walk away from this activity knowledgeable and excited to learn about the impact of the war.
I received the Zinn Education Project materials and I immediately flipped through the book and taught the U.S. – Mexico War lesson. It was so wonderful to see a group of usually unmotivated students engaged in the lesson that I called in another teacher to see this group of students actively involved in the activity.
I use lessons from the Zinn Education Project because they are relevant, factual, and inspiring. Lessons like The U.S. – Mexico War shed light on aspects of our shared American heritage that are often overlooked. These lessons give a voice to great Americans who are too often forgotten.
Even though my students don’t quite understand it yet, I can see that a close examination of people’s history empowers my students to use their own voices. |
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 July 25
Explanation: Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way Galaxy. M101 was also one of the original spiral nebulae observed by Lord Rosse's large 19th century telescope, the Leviathan of Parsontown. Recorded at infrared wavelengths by the Spitzer Space telescope, this 21st century view shows starlight in blue hues while the galaxy's dust clouds are in red. Examining the dust features in the outer rim of the galaxy, astronomers have found that organic molecules present throughout the rest of M101 are lacking. The organic molecules tracked by Spitzer's instruments are called polycyclic aromatic hydrocarbons (PAHs). Of course, PAHs are common components of dust in the Milky Way and on planet Earth are found in soot. PAHs are likely destroyed near the outer edges of M101 by energetic radiation in intense star forming regions. Also known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major, about 25 million light-years away.
Authors & editors:
Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
A service of: ASD at NASA / GSFC
& Michigan Tech. U. |
How loud would a literal ‘shot heard round the world’ be?
Short answer: To be heard around the world, a 20 Hz sound would have to be nearly 400 dB, which is impossibly loud.
Long answer: Sounds get weaker with distance. When you make a noise the soundwave travels outward in a shell, which is an expanding sphere with the source at the center. By the inverse square law and conservation of energy, the surface area of that sphere grows and the loudness of the sound decreases, which is one reason why sound volume fades at a distance. The other reason is atmospheric attenuation. Sound doesn’t carry forever. As the wave travels it will lose a little bit of the energy to heating the air, eventually dissipating beyond detectability.
So what if we wanted to make a sound that could be heard on the other side of the earth?
My first thought is that the inverse square law isn’t directly applicable. A super loud transglobal soundwave isn’t really expanding like a sphere but more like a circular ripple on the surface of the pond, where the pond is like the atmosphere. With the distances we’re considering the ‘roof’ of the atmosphere doesn’t really matter. In this case, the soundwave spreads out with just an inverse law, not inverse square, so it will carry farther with less loss. Additionally, after this ripple crosses half of the world it will start to refocus itself, eventually recombining at the antipode (that’s one of my favorite words, it means the exact opposite side of the earth).
You can see the same effect scaled down in videos of waves in water droplets in zero gravity:
For example, if there was a bang at the North Pole, that wave would travel down over the northern hemisphere and would spread and weaken along the way, but after passing the equator the wave would start to refocus. Eventually it would converge at the South Pole, and in the absence of attenuation the wave would have the same volume it had at the North Pole!
As a tangent, the same concept can be used in ‘sonic therapy’ to focus energy at a point inside the body. By placing a speaker and a patient at the foci of an ellipse soundwaves can be focused onto a kidney stone, causing it to crumble. Check out this video from a elliptical ripple-tank:
The attenuation is a different matter. Attenuation of sound depends on frequency, and low frequencies carry much farther than high ones. Humans can hear between 20 Hz and 20 kHz, and in moderate humidity a low frequency of 20 Hz has an attenuation of about 0.02 dB/km, while a high frequency of 20 kHz has an attenuation of 500 dB/km . Basically, bass carries.
So how loud would it have to be?
It turns out that if you want to be heard at the antipode you only need to worry about attenuation since the sound is refocusing itself. For a monotonic 20 Hz pitch to travel half of earth’s circumference of 20,000 km with attenuation of 0.02 dB/km, this sound needs to be at least 400 dB at the source.
How loud is this? Remember that decibels are a logarithmic scale – adding +10 dB means the sound is 10x louder! The threshold for pain is about 120 dB, and immediate damage and deafness can occur at 140 dB . This 400 dB sound is 1026 times louder than sounds that can cause deafness! The power in this sound is substantially greater than the power output from the sun’s surface! To be a literal ‘shot heard round the world’ it would literally be the last thing heard by most of the world because of the ensuing mass deafness.
So I suppose the answer isn’t “400 dB” but rather “it’s impossible.” It’s safe to say we’re well outside the regime described by elementary acoustics.
Of course, it’s only impossible if you want the sound to be heard. As a general rule of thumb attenuation scales with frequency, so we can make a sound that can carry farther by lowering the pitch to infrasound (another favorite word – it means sound that’s too low in pitch to be heard, just like how infrared light is just past visible red on the EM spectrum). As I said before, bass carries.
In fact, this is exactly what happened when the island volcano of Krakatoa erupted in the Pacific in 1883. The sound it made was recorded as 172 dB from 100 miles away; sailors within this range were immediately deafened by the blast.
It wasn’t audible to humans on the opposite side of the planet, but the pressure of the passing infrasound wave was detectable in mercury barometers. In fact, the passage of this wave was recorded up to seven times in some places, meaning it went around the world three and a half times!
special thanks to /u/therationapi
image credit: Wikimedia Commons
Have a question? Send it to [email protected] |
Understand how to communicate complex information to lay audiences
In a time when experts are all too often ignored or misunderstood, communicating complex information accurately to inexperienced audiences is a prized skill. This course will help your develop this skill. You will learn specific strategies to get your ideas across in a more impactful way; discovering how to organise your messages, techniques for explaining abstract ideas, and how to use and create visuals to enhance understanding.
What topics will you cover?
Three different explanation models: quasi-scientific, transformation and elucidating
Barriers to effective explanations including myths
The importance of audience analysis in effectively communicating complex ideas
Using analogies to explain abstract ideas.
Effective organization in oral presentations
Creating organisational structures.
Producing charts which enhance audience understanding.
What will you achieve?
By the end of this course you will be able to:
Use different methods to overcome the barriers that most audiences face when learning complex information
Apply practices for organizing and explaining ideas orally
Design presentation slides for improved audience understanding
Communicate complex ideas or material to various audiences.
This course is for anyone who has to explain new ideas to lay publics where there are vast differences between the speaker and their audience in their command of the content. It will be of particular use to teachers, scientists, communication experts, financial experts and medical experts. |
When people lose their ability to memorize data they have amnesia. Amnesia also refers to an inability to recall information that is stored in memory. In simple terms, amnesia is the loss of memory. The causes of amnesia may be organic or functional. Organic causes of amnesia may include brain damage through injury, or the use of specific drugs - usually sedative drugs. Amnesia may be one of the symptoms of some degenerative brain diseases, such as Alzheimer's disease.
Many people with amnesia find it helpful to use smart technology, such as a smartphone or a hand-held tablet device. With some training and practice, even people with severe amnesia can use these electronic organizers to help with day-to-day tasks. For example, smartphones can be programmed to remind them about important events or to take medications.
Low-tech memory aids include notebooks, wall calendars, pill minders, and photographs of people and places.
Transient global amnesia usually affects patients between the ages of 40 and 80. Patients with this condition are often described – wrongly – as being confused. It presents classically with an abrupt onset of severe anterograde amnesia. It is usually accompanied by repetitive questioning. The patient does not have any focal neurological symptoms. Patients remain alert, attentive, and cognition is not impaired. However, they are disoriented to time and place. Attacks usually last for 1–8 h but should be less than 24 h. |
Lesson Plan #1
Lesson Topic: Seasons
Students will be able to determine the ways in which deciduous trees lose their leaves by investigating fallen leaves and how the weather changes throughout the seasons.
Students will obtain knowledge about why and what causes the weather to change throughout the seasons.
Plastic garbage bag
These sites tell why leaves change color
I like the last site the best.
These sites are about trees
This first site tells about tree related resources on the web:
and this next site is with regard to the homepage that I found the first site
this site is very informational
I will use the PRESENT, ACTIVE LEARNING, AND COLLABORATIVE methods of teaching for this lesson plan. I also used the FRAME and EXPLORE models.
- PRESENT: have a pile of leaves on a garbage bag located in the middle of the floor in the classroom. When all of the students are in the room, the teacher will jump into the big pile of leaves causing excitement among the children.
- ACTIVE LEARNING: Offer the children the chance to play in the leaves. Have them compare the leaves and separate them into similar characteristic categories.
- Ask students what the trees look like when all of the leaves are gone, when new leaves will form, the colors that they will be before they fall off of the trees and when they are growing back on, the types of weather that occurs during the times that the leaves grow, fall, and are not on the trees, and how the weather changes or how it might play a role in the process of the leaves.
- Have children use the internet to locate sites in which they can obtain information about leaves, trees, and the weather.
- Children can work in small groups of 2 or 3 in order to investigate this topic
Show an animation of trees through the seasons growing leaves, changing colors, and losing their leaves.
From the internet, locate sites about trees, weather, and leaves (look above)
The information will be given by scientific experts from the sites and other resources that the students used to locate information. |
A BRIEF HISTORY OF MAPS.
As early as the 15th century a team of Portuguese explorers and tradesmen, under the leadership of Prince Henry de Avis made big steps in cartography. The 15th and 16th centuries saw the dawn of exploration so the need for charts, which showed coastlines compass lines and rivers, were very important. These charts were used for military purposes as well as for trade so were not generally accessible
Before this important first step ‘finding the way’ had been largely intuitive, relying on word of mouth and the sharing of experience.
In the 15th century however maps depicted a world divided into three continents some were real and some remained imaginary.
Early maps were drawn by hand as were the decorations, as a result they were rare. It wasn’t until the 15th century when maps were printed; using carved wooden blocks,
that they became more available. In 1540 Sebastian Munster published ‘Geographia’, which established a new standard in the field of cartography.
Following these wooden blocks came copper plate engraving in the 16th century. The voyages of Columbus to the New World started the further development of maps. A map created by Waldseemuller in 1507 was the first world map to show America.
Over the centuries mapping improved as the methods available became more sophisticated. Knowledge about uncharted areas was supported by aerial photography, which meant they to could be recorded.
In 1747 in Britain a royal survey was commissioned the outcome of which was The Duke of Cumberland map. This was a very important step as it led to the principal triangulation of Great Britain, which then led to the development of Ordinance Survey.
In 1791 the mapping of the South of Great Britain began. The Board of ordinance started the military survey under the leadership of William Roy.
A decade later the first 1inch to the mile was published and from 1801-1821 one third of Wales and England were charted.
An example of the commitment to making accurate maps was so high by those involved that in 1891 a Mr. Thomas Colby walked 586 miles in 22days to establish the correct details of an area being mapped.
The Ordinance Survey act in 1841 meant that people were given access to property in order to survey an area.
Another important step in mapping came when Henry James the director general saw the importance photography, which could allow maps to become cheaper and therefore more accessible.
Maps historically have always held great importance as they were in World Wars 1 and 2. When maps of the areas involved were created.
Other significant activities undertaken were; in 1935 the massive job of triangulating Britain, the launch of the National Grid system with a metre as the unit of measurement and in 1995 the Ordinance Survey digitised mapping thus allowing the U.K. to be the first country to develop electronic mapping. A far cry from Claudius Ptolemy’s ‘Guide to Geography’ in the 2nd. Century A.D.
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Talk in the classroom is a crucial part of the learning process for all children. Sadly, it is one which is often either neglected or marginalised. It is my view that high quality talk supports children in their attempts to internalise the patterns, structures and methods necessary to succeed in all curriculum subjects. Additionally, placing an emphasis on the development of high quality talk develops higher order thinking skills.
A moment’s thought shows us the instinctive importance of talk in our lives. Most adults, as well as children, share an intuitive view that talking things through helps us to make up our minds: in essence, talking helps us understand what we actually think. I would also argue that talking through our thoughts often changes and reshapes them. I use the phrase “Talk is Thought” to describe its impact on all areas of the curriculum – a principle I share with teachers across the UK.
A great deal of research has been done in recent years that identifies talk as a crucial part of the learning process. For example, Debra Myhill’s work highlights the central influence of talk in developing children’s learning. Work by Resnik and Delvin has also identified talk as an essential part of successful learning in maths. Moreover, despite the great current debate among teachers with regard to the new National Curriculum, it appears that even this document recognises the importance of talk: “The National Curriculum for English reflects the importance of spoken language in pupils’ development across the whole curriculum – cognitively, socially and linguistically. Spoken language underpins the development of reading and writing. The quality and variety of language that pupils hear and speak are vital for developing their vocabulary and grammar and their understanding for reading and writing.”
If you’re interested in creating a better climate for talk in your classroom, the following six principles below will show you how.
Principle 1: Talk for Learning should be collaborative
Place a great emphasis in your classroom on using collaboration and discussion to move learning forward – children should support each other as learners and borrow ideas from each other and from you. If all your children are always willing to share, and you no longer need to rely on strategies such as ‘hands up’ when asking questions, you have successfully created a collaborative climate.
Principle 2: Value every idea, model using the best
As teachers, we know that we learn by making mistakes. However, we cannot get away from the fact that we now teach in a data driven, non-negotiable educational climate. I increasingly visit schools and find teachers living in a bubble of stress and anxiety, with a fixed view that child X needs to move from A to Z within a limited period of time. It is obviously our responsibility as teachers to ensure that our children do make progress. However, to achieve this we must remember that we came into teaching to inspire children, not to undermine them – every idea has value and it is vital that all children feel they are able to contribute in a meaningful way. We need classrooms where children take risks, make mistakes and then learn from them. Therefore, when doing shared writing or discussing ways in which to solve a maths problem, allow children to contribute any idea and ensure that it is the class that makes the decision as to which idea is the best. Worst case scenario, they’re wrong and they find this out through problem solving.
Principle 3: Experience is everything
No matter what the subject, a rich, meaningful experience to which children can relate will not only deepen their understanding, but ultimately help them to internalise the subject. Once they’ve had the experience, children need opportunities to discuss it, explore it, participate in it and live it. If they experience it, they will be able to discuss it. If they can discuss it, they will begin to apply it. If they can apply it, they will have learnt it. And, crucially, they will have enjoyed the process.
Principle 4: Orally rehearse to internalise patterns and structures
Oral rehearsal of stories, maths problems, science investigations and real-life events can help children not only internalise patterns and structures, but also develop their thinking and understanding. In literacy, encourage children to learn stories orally. Once children can say the story and have internalised the patterns, begin to encourage them to innovate and invent. In maths, put your core mathematical language into a story involving a mathematical problem. Again, once children can speak the language, make up their own maths stories using the same language. At this stage, they are not only able to make up their own problems, they are able to apply the knowledge and understanding of mathematical language and concepts that they have internalised to solve new problems.
Principle 5: Share learning experiences with your class
This is absolutely vital. We all know how important high quality modelling is in any subject. Yet, when modelling, we are often faced with a dilemma – how do you ensure that all 30 children in your class are engaged, active and learning? The answer is that you cannot. If you’re simply showing the children what to do, a fair proportion of the class is likely to become disengaged. And the more complex the procedure you are demonstrating (the ones where you really need their 100 per cent focus), the more likely they are to switch off. So don’t model. Share. Show the children a problem or introduce the writing topic and ask them for their ideas. Direct the flow of the conversation, possibly offer an idea or two of your own if they get stuck, but ensure the impetus comes from them. They need to understand that you are a learner too and that their ideas are just as valid as yours. It may seem contrived, but sometimes it’s useful to even make a little error or come up with a bland idea, just to give them the opportunity to impress you with how much better their thoughts are. Pupil-led discussion has led to some of the best writing I have ever seen and some of the most interesting scientific discussions. It’s all right for them to find out that you don’t know everything and that your ideas aren’t always the best. In fact, it’s fantastic! They will be much more open to sharing their ideas and offering their own suggestions if they discover that you aren’t omniscient.
Principle 6: Technology talks
When working with a reception teacher at the start of this term, I noticed the majority of children came straight in and attempted to use the traditional computer monitors like touch screens. These children have grown up around iPads, tablets and smart phones and, as teachers, we need to recognise this when planning interactive, talk-led activities. For instance, we might use technology to offer children an alternative way to present their ideas. Either way, it needs to be embedded in our teaching, just as it is embedded in our lives. In summary, Talk for Learning is not a new methodology – it is based on principles that have been around for years. Giving children the opportunity to experience and discuss their work helps them to see how it relates to their lives and to internalise the concepts. Placing an emphasis on the validity and value of children’s ideas encourages them to be creative and enterprising. Seeing their teacher learning alongside them motivates them to question and engage with their task. Applying the principles of Talk for Learning will help us to show children that they are valued, capable, creative individuals whose education is not an ordeal to be struggled through in silence, but an experience in which they can and should, be vociferous, imaginative and thoughtful participants.
CHATTER YOUR WAY THROUGH THE CURRICULUM…
A class mascot can be used in any subject to inspire, excite and foster high quality talk. For me, it all started with Monkey. Back when I was an NQT, I introduced Monkey as a class mascot for my year 4 class. I used to choose one child each week to take Monkey home over the weekend and return on Monday with a diary entry about their experience with him. Every child always wanted Monkey, and when it was eventually their turn, they would always come back with outstanding writing to share. The reason is simple: the stimulus was exiting and they had a clear audience and purpose. Over the years, Monkey has had many adventures. He has been to various supermarkets, parks, and play areas and to some more exotic locations such as Lapland.
Probably my favourite ever example came from a year 2 teacher who I trained recently. She introduced a bear to her class, who they named Bubbles. On the third week of term, the girl chosen to take Bubbles home decided that she didn’t like his name, so she dragged her parents to the registry office and came back on Monday with photos of Bubbles outside the registry office and a new name certificate stapled into the diary. Isn’t it amazing that such a simple idea can provoke such a reaction? The challenge is to replicate this reaction and find similar ways to inspire and excite our children.
I also introduced a Maths Monster, who would go home with a different child each week. The aim was for the child to find as many real-life opportunities as possible to do maths with the monster over the weekend. On the Monday, the child would bring back his/her Monster Maths journal full of the problems they had solved together. The journal would include photos and workings. It acted as an amazing stimulus for high quality talk and discussion when back in class. Examples included using Dad’s electricity bill to forecast next month’s payments, calculating the cost of a shopping trip, measuring out cake ingredients and working out if there was enough space in a room for a new bed of a particular length.
Published on 14 June 2014 |
- Activity One: Making the Literary Connection to Alice's Adventures in Wonderland
As a lead-in activity, read portions of Alice's Adventures in Wonderland, which promote discussions related to immigration.
- Activity Two: Discovering the Common Themes of the Immigrant Experience - Connecting to Personal Experience
Students brainstorm the common threads of the immigrant experience and relate this experience to their own experiences with relocation and adjustment to new surroundings.
- Activity Three: Analyzing Primary Source Texts to Identify Common Themes of the Immigrant Experience Students use teacher-selected primary sources to identify the common themes of the immigrant experience.
- Activity Four: Introduction to Photographic Analysis
Students combine observations with background knowledge to make deductions about photographs related to the theme of immigration.
(Note: This activity can use any theme that fits into the curriculum.)
- Activity Five: Curating a Photo Exhibit of "The Immigrant Experience"
Students become curators of a photo exhibit entitled "The Immigrant Experience."
- Activity Six: Grand Opening of "The Immigrant Experience"
Students combine their posters to create a poster display for parents and community members.
As a lead-in activity, read portions of Lewis Carroll's Alice's Adventures in Wonderland to the students for a few minutes every day. You may be able to find the book online or in a local library.
Although there are many themes for discussion, for the purposes of this unit, highlight scenes that relate to the discomfort experienced by Alice because of the unpredictability of her experiences in Wonderland.
The four following scenes can be highlighted for introductory discussions about the immigrant experience:
Chapter IV: The Rabbit Sends In a Little Bill
"It was much pleasanter at home," thought poor Alice, "when one wasn't always growing larger and smaller, and being ordered about by mice and rabbits. I almost wish I hadn't gone down that rabbit-hole - and yet - it's rather curious, you know, this sort of life! I do wonder what can have happened to me! When I used to read fairy tales, I fancied that kind of thing never happened, and now here I am in the middle of one!"
Chapter V: Advice from a Caterpillar
The Caterpillar and Alice looked at each other for some time in silence: at last the Caterpillar took the hookah out of its mouth, and addressed her in a languid, sleepy voice.
"Who are You?" said the Caterpillar.
This was not an encouraging opening for a conversation. Alice replied, rather shyly, "I - I hardly know, Sir, just at present - at least I know who I was when I got up this morning, but I think I must have been changed several times since then."
Chapter VI: Pig and Pepper
"Cheshire Puss," she began, rather timidly, as she did not at all know whether it would like the name: however, it only grinned a little wider. "Come, it's pleased so far," thought Alice, and she went on. "Would you tell me, please, which way I ought to go from here?"
"That depends a good deal on where you want to get to," said the Cat.
"I don't much care where - " said Alice.
"Then it doesn't matter which way you go," said the Cat.
" - so long as I get somewhere," Alice added as an explanation.
"Oh, you're sure to do that," said the Cat, "if you only walk long enough."
Alice felt that this could not be denied, so she tried another question. "What sort of people live about here?"
"In that direction," the Cat said, waving its right paw round, "lives a Hatter: and in that direction," waving the other paw, "lives a March Hare. Visit either you like: the're both mad."
"But I don't want to go among mad people," Alice remarked.
"Oh, you can't help that," said the Cat: "we're all mad here. I'm mad. You're mad."
"How do you know I'm mad?" said Alice.
"You must be," said the Cat, "or you wouldn't have come here."
Chapter VIII: The Queen's Croquet-Ground
"I don't think they play at all fairly," Alice began, in rather a complaining tone, "and they all quarrel so dreadfully one can't hear oneself speak - and they don't seem to have any rules in particular: at least, if there are, nobody attends to them - and you've no idea how confusing it is all the things being alive: for instance, there's the arch I've got to go through next walking about at the other end of the ground - and I should have croqueted the Queen's hedgehog just now, only it ran away when it saw mine coming!"
Actvity 2: Discovering the Common Themes of the Immigrant Experience - Connecting the Personal Experience
Students brainstorm the common threads of the immigrant experience. Through a teacher/student discussion of their own relocation experiences (city to city, state to state, or country to country), identify reasons for relocating, difficulties encountered, and the successes or failures of adjustments to new surroundings.
Use the following questions to guide your discussion:
- Have you ever moved to a new place? If yes, do you remember feeling scared? Unsure? Excited? Angry? Relieved? Sad? Out of place?
- If you have moved, how did you feel in your new location after three months? Six months? One year? Did you feel as if you would ever fit in? Did you make friends quickly or slowly? What did you miss?
- Have you ever lived in a place where the people did not speak your language? How did that feel?
- If you belong to a military family, where have you lived? Have you moved often? Can you describe your experiences? If you have lived in a foreign country, were you scared about moving there? Was the food strange to you?
- Have you ever known someone from another country who has moved (immigrated) to the United States?
- Can you think of several possible reasons why a person immigrates to the United States?
- Did any of your ancestors emigrate from another country? Which country or countries?
- Do you think that many immigrants to the United States face discrimination? Economic problems? Racial prejudice? Religious differences? Language difficulties? Educational challenges?
- Do you think that all immigrants should learn English? Should immigrants keep their ties to their ethnic and racial heritage? Do you think that immigrant teenagers have difficulty being part of both the American culture and their own cultures?
- What percentage of the U.S. population do you think is foreign-born? How could you find the answer?
Through student/teacher inquiry the following common themes of immigration should be identified and defined: motivation to emigrate, assimilation, economic issues (including living and working conditions), education, choice of destination, language difficulties, and issues of prejudice.
Students use teacher-selected primary sources to identify the common themes of the immigrant experience.
- Divide students into groups.
- Assign each group to read a primary source oral history or narrative from the American Memory collections as homework. The oral histories listed below work well for a cross-section of immigrant experiences, or you may explore the collections on your own.
- One student in each group will be selected as the group's discussion leader for the following day.
- The group will choose a historian to record the group's conclusions. The groups should record their thoughts on the Primary Source Analysis Tool. Select questions from the Analyzing Oral Histories teacher's guide to focus the group work, and select additional questions to focus and prompt further discussion.
The following oral histories are from American Life Histories: Manuscripts from the Federal Writers' Project, 1936-1940:
- Gardenia Banta - Describes the experiences of an African-American woman who moved to New York City in 1888 during the post-Civil War northern migration. She tells of her previous life in Savannah, Georgia, and of the difficulties of moving north after her father died.
- Philip Dash - This Russian Jewish immigrant describes his work in the shoe industry, his union involvement, and living in poverty in Brooklyn, New York.
- Mr. and Mrs. Elias Pederson - Mr. Pederson was born in Wisconsin in 1849, the year after his parents emigrated from Norway. He and his wife recall plowing the fields with oxen, loading heavy railroad ties onto a sleigh, and carrying butter and eggs to nearby Pokerville to exchange for groceries.
- Florence Cravens [I was born in Austin, Texas] - In 1886, Mrs. Cravens moved west with her family from Austin, Texas, on an immigrant train of covered wagons. She recalls hearing wolves, coming upon the newly dug grave of a child, a shooting, selling mesquite roots for firewood, the death of her mother, and a smallpox epidemic.
- Albert Zeigler - A German immigrant, Mr. Zeigler describes running a dry goods store with his brother in New Mexico, selling stove pipe hats to Apache Indians, and the impact of gold mining on the town in the 1880s.
- Giacomo Coletti - This narrative describes an Italian granite worker's life in Montpelier, Vermont, including the importance of family celebrations, living in poverty, working in "the sheds," and working with other immigrant groups.
The following oral history is from Pioneering the Upper Midwest: Books from Michigan, Minnesota, and Wisconsin, ca. 1820-1910:
- Chrysostom Verwyst [Reminiscences of a pioneer missionary] - A pioneer missionary immigrant from Holland, Mr. Verwyst describes his train ride to Hollandtown, Wisconsin, and how his family carved a farm out of the woods and meadows. His memoirs contain accounts of festive celebrations, clothing, agricultural practices, and local community life.
- Choose a photograph from the American Memory collections and project it on a screen. Italian bread peddlers, from the Detroit Publishing Company collection, works well for this activity.
- Lead the students through a group photographic analysis activity, using the questions from the teacher's guide Analyzing Prints and Photographs to focus and prompt discussion.
- Students work in pairs to search for and select a photograph from the Detroit Publishing Company collection to analyze. Search for photographs illustrating the theme of immigration by entering one of the following keywords:
- Street scene
Students become curators of a photo exhibit entitled "The Immigrant Experience."
- Hand out copies of The Immigrant Experience - A Photographic Exhibit instruction sheet and review with students.
- Students choose an immigration-related theme to research.
- In pairs, students search the American Memory collections and select and print five photographs depicting their immigration theme.
- Each of the photographs should be accompanied by text that explains the photo's relationship to the chosen theme.
- Students research their chosen theme and explain it in a written essay.
- As a guide, the students complete an Analyzing Prints and Photographs worksheet used in Activity Four for each of the five selected photographs.
Students combine their posters to create a poster display on a classroom wall. At the exhibit opening, students view all the displayed photos to reinforce their understanding of the various themes of immigration. If possible, display selected posters at a school "technology night" or other event, where students can explain the project to visiting parents and community members.
After the exhibit opening, guide a wrap-up discussion of the immigrant experience. |
NASA's Landsat Data Continuity Mission (LDCM) spacecraft was successfully placed in orbit earlier this week. The mission marks the continuation of the 40-year Landsat Earth-observation program, which aids in the study of dynamic and ongoing changes to the planet.
The spacecraft was lifted into orbit by an Atlas V rocket, taking off from Vandenberg Air Force Base in California, before separating from the rocket 79 minutes after launch. The satellite, now in orbit at 680 km (422 miles), will reach its operational altitude of 705 km (438 miles) within two months, and will undergo a full three months of testing before becoming operational. It will then be renamed Landsat 8 and control will be transferred to NASA's mission partner, the Department of the Interior's U.S. Geological Survey (USGS), which will continue the Landsat program.
Landsat is the longest continuous data record of the Earth's surface and is a key tool in the study of climate change. NASA Administrator Charles Bolden commented on the significance of the program, stating that it “has led to the improvement of human and biodiversity health, energy and water management, urban planning, disaster recovery and agriculture monitoring – all resulting in incalculable benefits to the U.S. and world economy.”
The Landsat 8 will orbit every 99 minutes and image the entire planet every 16 days. It carries more advanced technology than its predecessors, including both the Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS). These instruments will make for improved reliability, sensitivity and data quality, while still maintaining compatibility with past Landsat data.
The OLI has fewer moving parts than the instruments it replaces and will capture visible, near infrared and shortwave infrared light. It will also observe high-altitude cirrus clouds, and monitor atmospheric aerosols and the water quality in lakes and coastal waters. The TIRS will monitor the temperature of the Earth's surface in two thermal bands, an improvement over the Landsat 7's single band instrument. These observations are used to analyze water consumption.
In 2008, NASA opened the doors to the Landsat data, allowing public access to its archives. That data was subsequently used in the creation of Google Earth Engine in 2012, a program that allows users to “zoom through” 13 years of Landsat imagery, providing a tangible insight into the changing face of the planet.
Check out the video below to see the LDCM spacecraft separating from the booster in orbit.
- Around The Home
- Digital Cameras
- Good Thinking
- Health and Wellbeing
- Holiday Destinations
- Home Entertainment
- Inventors and Remarkable People
- Mobile Technology
- Urban Transport
- Wearable Electronics |
Childhood Apraxia of Speech and Reading Help
Reading is a fundamental skill needed for academic success. In today’s world, strong literacy skills are essential. Children who struggle in reading tend to experience extreme difficulties in all content areas, as every subject in school requires reading proficiency. When children are then faced with further struggles such as speech production and receptive and expressive language difficulties, the effects can be even more detrimental.
To read proficiently, a child requires highly integrated skills in word decoding and comprehension and draws upon basic language knowledge such as semantics, syntax, and phonology. Children with speech and language impairments, such as Childhood Apraxia of Speech (CAS), have deficits in phonological processing. For these children, phonemic awareness, motor program execution, syntax and morphology will interfere with the ability to acquire the skills necessary to become proficient readers.
So, how does a child with CAS learn how to read?
– With a multisensory, structured, systematic, cumulative and repetitive reading program plus intensive therapy in phonemic awareness and phonological processing!
What is multisensory teaching?
Multisensory teaching is an important aspect of instruction for the child with CAS and is used by most clinically trained therapists. Multisensory teaching utilizes all the senses to relay information to the child. The teacher accesses the auditory, visual, and kinesthetic pathways in order to enhance memory and learning. Links are consistently made between the visual (language we see), auditory (language we hear), and kinesthetic-tactile (language we feel) pathways in learning to read. For example, when learning the letter combination “ong” the child might first look at it and then have to trace the letters in the air while speaking out loud. This combination of listening, looking, and moving around creates a lasting impression for the child as things will connect to each other and become memorable.
What is a structured, systematic, cumulative and repetitive reading program?
The other significant component in helping a child with CAS learn to read is utilizing an Orton-Gillingham approach. In Orton-Gillingham, the phonemes are introduced in a systematic, sequential and cumulative process. The Orton-Gillingham teacher begins with the most basic elements of the English language. Using repetition and the sequential building blocks of our language, phonemes are taught one at a time. This includes the consonants and sounds of the consonants. By presenting one rule at a time and practicing it until the child can apply it with automaticity and fluency, the child will have no reading gaps in their word-decoding skills. As the child progresses to short vowels, he or she begins reading and writing sounds in isolation. From there the child progresses to digraphs, blends and diphthongs.
Children are taught how to listen to words or syllables and break them into individual phonemes. They also take individual sounds and blend them into a word, change the sounds in the words, delete sounds, and compare sounds. For example, “…in the word bread, what is the first sound you hear? What is the vowel sound you hear? What is the last sound you hear? Students are also taught to recognize and manipulate these sounds. “…what sound does the ‘ea’ make in the word bread? Say bread. Say bread again but instead of the ‘br’ say ‘h.’- HEAD!
Every lesson the child learns is in a structured and orderly fashion. The child is taught a skill and doesn’t progress to the next skill until the current lesson is mastered. As children learn new material, they continue to review old material until it is stored into the child’s long-term memory. While learning these skills, the child focuses on phonemic awareness. There are 181 phonemes or rules in Orton-Gillingham for students to learn. More advanced readers (middle school) will study the rules of English language, syllable patterns, and how to use roots, prefixes, and suffixes to study words. By teaching how to combine the individual letters or sounds and put them together to form words and how to break longer words into smaller pieces, both synthetic and analytic phonics are taught throughout the entire Orton-Gillingham program.
What is phonological processing?
The key to the entire reading process is phonological awareness. This is where a child identifies the different sounds that make words and associates these sounds with written words. A child cannot learn to read without this skill. In order to learn to read, children must be aware of phonemes. A phoneme is the smallest functional unit of sound. For example, the word ‘bench’ contains 4 different phonemes. They are ‘b’ ‘e’ ‘n’ and ‘ch.’
Some examples of phonological awareness tasks include:
- Identifying rhymes – “Tell me all of the words you know that rhyme with the word BAT.”
- Segmenting words into smaller units, such as syllables and sounds, by counting them. “How many sounds do you hear in the word CAKE?”
- Blending separated sounds into words – “What word would we have if we blended these sounds together: /h/ /a/ /t/?”
- Manipulating sounds in words by adding, deleting or substituting – “In the word LAND, change the /L/ to /B/.” “What word is left if you take the /H/ away from the word HAT?”
Through phonological awareness, children learn to associate sounds and create links to word recognition and decoding skills necessary for reading. Research clearly shows that phoneme awareness performance is a strong predictor of long- term reading and spelling success for children with speech and language disabilities. In fact, according to the International Reading Association, phonemic awareness abilities in kindergarten (or in that age range) appear to be the best single predictor of successful reading acquisition!
What kind of reading intervention is necessary?
For the child diagnosed with Childhood Apraxia of Speech (CAS) that is already behind his peers in phonemic awareness and reading, the instruction will need to be delivered with great intensity. Keep in mind that this child is behind his classmates and must make more progress if he is to ever catch up. The rest of the class does not stand still to wait, they continue forward. Taking a few lessons once or twice a week will never give the student with CAS the opportunity to catch up. He must make a giant leap; if not, he will always remain behind.
A child with a speech and language disorder may require as much as 150 to 300 hours of intensive instruction if he is ever going to close the reading gap between himself and his peers. The longer identification and effective reading instruction are delayed, the longer the child will need to catch up. In general, it takes 100 hours of intensive instruction to progress one year in reading level. The sooner this remediation is completed, the sooner the child can progress forward with his peers.
Children with Childhood Apraxia of Speech need more structure, repetition and differentiation in their reading instruction. They need to learn basic language sounds and the letters that make them, starting from the very beginning and moving forward in a gradual step by step process. This needs to be delivered in a systematic, sequential and cumulative approach. For all of this to “stick” the children will need to do this by using their eyes, ears, voices, and hands.
Karina Richland, M.A. is the Founder of PRIDE Learning Centers, located in Los Angeles and Orange County. Ms. Richland is a certified reading and learning disability specialist. Ms. Richland speaks frequently to parents, teachers, and professionals on learning differences, and writes for several journals and publications. You can reach her by email at [email protected] or visit the PRIDE Learning Center website at: www.pridelearningcenter.com |
The European Space Agency's Cluster mission has revealed a new creation mechanism of ‘killer electrons’ - highly energetic electrons that are responsible for damaging satellites and posing a serious hazard to astronauts.
Over the past five years, a series of discoveries by the multi-spacecraft Cluster mission have significantly enhanced our knowledge of how, where and under which conditions these killer electrons are created in Earth’s magnetosphere.
Early satellite measurements in the 1950s revealed the existence of two permanent rings of energetic particles around Earth.
Usually called the ‘Van Allen radiation belts’, they are filled with particles trapped by Earth’s magnetic field. Observations showed that the inner belt contains a fairly stable population of protons, while the outer belt is mainly composed of electrons in a more variable quantity.
Some of the outer belt electrons can be accelerated to very high energies, and it is these ‘killer electrons’ that can penetrate thick shielding and damage sensitive satellite electronics. This intense radiation environment is also a threat to astronauts.
For a long time scientists have been trying to explain why the number of charged particles inside the belts vary so much. Our major breakthrough came when two rare space storms occurred almost back-to-back in October and November 2003.
During the storms, part of the Van Allen radiation belt was drained of electrons and then reformed much closer to the Earth in a region usually thought to be relatively safe for satellites.
When the radiation belts reformed they did not increase according to a long-held theory of particle acceleration, called ‘radial diffusion’. Radial diffusion theory treats Earth’s magnetic field lines as being like elastic bands.
If the bands are plucked, they wobble. If they wobble at the same rate as the particles drifting around the Earth then the particles can be driven across the magnetic field and accelerated. This process is driven by solar activity.
Instead, a team of European and American scientists led by Dr Richard Horne of the British Antarctic Survey, Oxford, UK, used data from Cluster and ground receivers in Antarctica to show that very low frequency waves can cause the particle acceleration and intensify the belts.
These waves, named ‘chorus’, are natural electromagnetic emissions in the audio frequency range. They consist of discrete elements of short duration (less than one second) that sound like the chorus of birds singing at sunrise. These waves are among the most intense in the outer magnetosphere.
The number of ‘killer electrons’ can increase by a factor of a thousand at the peak of a magnetic storm and in the following days. Intense solar activity can also push the outer belt much closer to Earth, therefore subjecting lower altitude satellites to a much harsher environment than they were designed for.
The radial diffusion theory is still valid in some geophysical conditions. Before this discovery, some scientists thought that chorus emissions were not sufficiently efficient to account for the reformation of the outer radiation belt. What Cluster has revealed is that in certain highly disturbed geophysical conditions, chorus emissions are sufficient.
Thanks to the unique multipoint measurements capability of Cluster, the characteristic dimensions of these chorus source regions have been estimated for the first time.
Typical dimensions have been found to be a few hundred kilometres in the direction perpendicular to the Earth’s magnetic field and a few thousands of kilometres in the direction parallel to this.
However, the dimensions found so far are based on case studies. “Under disturbed magnetospheric conditions, the chorus source regions form long and narrow spaghetti-like objects. The question now is whether those very low perpendicular scales are a general property of the chorus mechanism, or just a special case of the analysed observations, said Ondrej Santolík, of Charles University, Prague, Czech Republic, and main author of this result.
Due to our increased reliance on space based technologies and communications, the understanding of how, under which conditions and where these killer electrons are created, especially during magnetic storm periods, is of great iimportance.
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Take an in-depth look at the evaporation portion of the water cycle with this worksheet on how clouds form! Use the word bank to fill in the diagram.
What is the difference between condensation and evaporation? Learn about natural cooling and heating processes that are caused by changing states of matter!
This fun and easy science fair project idea explains the process of transpiration in plants and how the number of stoma affects water loss.
Did you know that ocean water is salty, but river water is not? Find out how fresh and salt water mix together in this water cycle worksheet.
Looking for a fourth grade worksheet to help your kid with science? This printable will test his knowledge of the water cycle.
Does your little scientist know the water cycle? Challenge her with this cut and paste activity where she'll label each part of this water cycle!
The water cycle plays a big role in weather patterns. Color this water cycle chart and get familiar with this cycle at work.
Start from water cycle precipitation from clouds and match parts of the cycle to this clear colorful image of a simple water cycle, using the helpful paragraph.
How do clouds form? Why does it rain? Help your student answer some of these questions by completing this water cycle worksheet.
Did you know that there is no new water on Earth? It all gets recycled and reused in a process that we call the water cycle. |
The standards for all world languages teachers and learners are:
- Communication The communication standard stresses the use of language for e-communication in "real life" situations. It emphasizes "what students can do with language" rather than "what they know about language." Students are asked to communicate in oral and written form, interpret oral and written messages, show cultural understanding when they communicate, and present oral and written information to various audiences for a variety of purposes.
- Cultures Cultural understanding is an important part of world languages education. Experiencing other cultures develops a better understanding and appreciation of the relationship between languages and other cultures, as well as the student's native culture. Students become better able to understand other people's points of view, ways of life, and contributions to the world.
- Connections World languages instruction must be connected with other subject areas. Content from other subject areas is integrated with world language instruction through lessons that are developed around common themes.
- Comparisons Students are encouraged to compare and contrast languages and cultures. They discover patterns, make predictions, and analyze similarities and differences across languages and cultures. Students often come to understand their native language and culture better through such comparisons.
- Communities Extending learning experiences from the world language classroom to the home and multilingual and multicultural community emphasizes living in a global society. Activities may include: field trips, use of e-mail and the World Wide Web, clubs, exchange programs and cultural activities, school-to-work opportunities, and opportunities to hear speakers of other languages in the school and classroom.
Our course offering and goals for classes:
The first two years of language study are devoted to acquiring the skills of daily communication, grammar, reading and writing, as well as an understanding of the culture.
The advanced levels (3, AP, IB HL 1 and IB HL2) include more comprehensive oral responses, more academic language, presentational language and a more intent study of the literature and values of the target cultures.
The Native / Fluent Speaker program
The ability to communicate with people from many different countries in an increasingly global economy has many advantages, including personal satisfaction and professional rewards. Whether in the public sector, private industry, or a service profession, knowing a second language is truly a remarkable skill that gives one an advantage when applying to many job opportunities. All world language classes require daily homework and frequent exams.
- Spanish 1 - IB
- French 1 to IB HL2
- Chinese (online)
- Bilingual Guitar Club
- Spanish Conversation Class
- Spanish National Honor Society (Sociedad Honoraria Hispánica - AATSP)
- National French Honor Society
- Experiential trips abroad like the one to Cuba
Benefits of Language Learning:
- With less than 20% of Americans speaking another language, being bilingual gives you a serious advantage on the job market. The Center for Latin American, Caribbean, and Latino Studies did a study in 2012 that found bilingual Latinos in New York City earning approximately $15,000 more annually than Latinos who only spoke English. Another estimate put the value of speaking a second language at $128,000 over 40 years. Not to mention it makes you more valuable to your employer and more likely to be sent on overseas assignments.
- Salary.com found that jobs where employees were required to speak more than one language paid 5-20% more per hour. In another study, MIT economist Albert Saiz reported that bilingual college graduates earn 2% higher wages on average, which The Economistbelieves can add up to an additional $67,000 in savings by retirement for this people.
- Bilingualism is Highly Valued on the Job Market
- Knowing another language makes your resume stand out in a huge pool of job applicants. National and multinational organizations of all types have a need for multilingual professionals and being one of them makes you a more versatile and highly valued employee.
- CNN recently reported that jobs in the field of translation are among the fastest growing occupations in the United States, with an anticipated 25,000 job openings by 2020.
- Being Bilingual Opens Up Interesting Cultural and Social Opportunities.
- When it comes to traveling, speaking the local language creates a much more immersive and authentic experience. You'll be able to talk directly with the locals, rent local apartments, bargain in the language (and get better deals), order the right food, and ask for directions when you get lost. Everything becomes more seamless… and more fun!
- You're able to truly connect with people by having an elaborate conversation with them in their native language.
- Speaking Another Language Boosts Long-Term Neurological Health Countless studies have also found that bilingual people develop dementia an average of 4.5 years later than older people who speak only one language. It doesn't prevent the disease, but the extra "gray matter" from the ACC compensates for the neural deterioration. Another study of 600 stroke survivors in India showed that bilinguals recovered twice as fast as monolinguals. It's also been documented that bilingual people have better planning and problem-solving skills overall.
Job Related benefits
- Creates greater sensitivity to language and a better ear for listening
- Improves a student's understanding of his/her native language
- Leaves students with more mental flexibility, critical thinking and creativity
- Enriches and enhances mental development
Positive effect on intellectual growth and academic achievement
- You become smarter - it improves the functionality of your brain by challenging it to recognise, negotiate meaning, and communicate in different language systems. This skill boosts your ability to negotiate meaning in other problem-solving tasks as well. Students who study foreign languages tend to score better on standardised tests than their monolingual peers, particularly in the categories of maths, reading, and vocabulary.
- You build multitasking skills - Multilingual people are skilled at switching between two systems of speech, writing, and structure. According to a study from the Pennsylvania State University, this “juggling” skill makes them good multitaskers, because they can easily switch between different structures.
- Your memory improves - Learning a language involves memorising rules and vocabulary, which helps strengthen that mental “muscle.” This exercise improves overall memory, which means that multiple language speakers are better at remembering lists or sequences. Studies show that bilinguals are better at retaining shopping lists, names, and directions.
- You become more perceptive - A study from Spain’s University of Pompeu Fabra revealed that multilingual people are better at observing their surroundings. They are more adept at focusing on relevant information and editing out the irrelevant. They’re also better at spotting misleading information.
- Your decision-making skills improve - According to a study from the University of Chicago, bilinguals tend to make more rational decisions. Any language contains nuance and subtle implications in its vocabulary, and these biases can subconsciously influence your judgment. Bilinguals are more confident with their choices after thinking it over in the second language and seeing whether their initial conclusions still stand up.
- You improve your English - Learning a foreign language draws your focus to the mechanics of language: grammar, conjugations, and sentence structure. This makes you more aware of language, and the ways it can be structured and manipulated. These skills can make you a more effective communicator and a sharper editor and writer. Language speakers also develop a better ear for listening, since they’re skilled at distinguishing meaning from discrete sounds. |
Mushroom poisoning is caused by the consumption of raw or cooked fruiting bodies (mushrooms, toadstools) of a number of species of higher fungi. The term toadstool (from the German Todesstuhl, death's stool) is commonly given to poisonous mushrooms, but for individuals who are not experts in mushroom identification there are generally no easily recognizable differences between poisonous and nonpoisonous species. Old wives' tales notwithstanding, there is no general rule of thumb for distinguishing edible mushrooms and poisonous toadstools. The toxins involved in mushroom poisoning are produced naturally by the fungi themselves, and each individual specimen of a toxic species should be considered equally poisonous. Most mushrooms that cause human poisoning cannot be made nontoxic by cooking, canning, freezing, or any other means of processing. Thus, the only way to avoid poisoning is to avoid consumption of the toxic species. Poisonings in the United States occur most commonly when hunters of wild mushrooms (especially novices) misidentify and consume a toxic species, when recent immigrants collect and consume a poisonous American species that closely resembles an edible wild mushroom from their native land, or when mushrooms that contain psychoactive compounds are intentionally consumed by persons who desire these effects.
Nature of Disease
Mushroom poisonings are generally acute and are manifested by a variety of symptoms and prognoses, depending on the amount and species consumed. Because the chemistry of many of the mushroom toxins (especially the less deadly ones) is still unknown and positive identification of the mushrooms is often difficult or impossible, mushroom poisonings are generally categorized by their physiological effects. There are four categories of mushroom toxins: protoplasmic poisons (poisons that result in generalized destruction of cells, followed by organ failure); neurotoxins (compounds that cause neurological symptoms such as profuse sweating, coma, convulsions, hallucinations, excitement, depression, spastic colon); gastrointestinal irritants (compounds that produce rapid, transient nausea, vomiting, abdominal cramping, and diarrhea); and disulfiram-like toxins. Mushrooms in this last category are generally nontoxic and produce no symptoms unless alcohol is consumed within 72 hours after eating them, in which case a short-lived acute toxic syndrome is produced.
Diagnosis of Human Illness
A clinical testing procedure is currently available only for the most serious types of mushroom toxins, the amanitins. The commercially available method uses a 3H-radioimmunoassay (RIA) test kit and can detect sub-nanogram levels of toxin in urine and plasma. Unfortunately, it requires a 2-hour incubation period, and this is an excruciating delay in a type of poisoning which the clinician generally does not see until a day or two has passed. A 125I-based kit which overcomes this problem has recently been reported, but has not yet reached the clinic. A sensitive and rapid HPLC technique has been reported in the literature even more recently, but it has not yet seen clinical application. Since most clinical laboratories in this country do not use even the older RIA technique, diagnosis is based entirely on symptomology and recent dietary history. Despite the fact that cases of mushroom poisoning may be broken down into a relatively small number of categories based on symptomatology, positive botanical identification of the mushroom species consumed remains the only means of unequivocally determining the particular type of intoxication involved, and it is still vitally important to obtain such accurate identification as quickly as possible. Cases involving ingestion of more than one toxic species in which one set of symptoms masks or mimics another set are among many reasons for needing this information. Unfortunately, a number of factors (not discussed here) often make identification of the causative mushroom impossible. In such cases, diagnosis must be based on symptoms alone. In order to rule out other types of food poisoning and to conclude that the mushrooms eaten were the cause of the poisoning, it must be established that everyone who ate the suspect mushrooms became ill and that no one who did not eat the mushrooms became ill. Wild mushrooms eaten raw, cooked, or processed should always be regarded as prime suspects. After ruling out other sources of food poisoning and positively implicating mushrooms as the cause of the illness, diagnosis may proceed in two steps. The first step, outlined in Table 1, provides an early indication of the seriousness of the disease and its prognosis.
As described above, the protoplasmic poisons are the most likely to be fatal or to cause irreversible organ damage. In the case of poisoning by the deadly Amanitas, important laboratory indicators of liver (elevated LDH, SGOT, and bilirubin levels) and kidney (elevated uric acid, creatinine, and BUN levels) damage will be present. Unfortunately, in the absence of dietary history, these signs could be mistaken for symptoms of liver or kidney impairment as the result of other causes (e.g., viral hepatitis). It is important that this distinction be made as quickly as possible, because the delayed onset of symptoms will generally mean that the organ has already been damaged. The importance of rapid diagnosis is obvious: victims who are hospitalized and given aggressive support therapy almost immediately after ingestion have a mortality rate of only 10%, whereas those admitted 60 or more hours after ingestion have a 50-90% mortality rate. Table 2 provides more accurate diagnoses and appropriate therapeutic measures. A recent report indicates that amanitins are observable in urine well before the onset of any symptoms, but that laboratory tests for liver dysfunction do not appear until well after the organ has been damaged.
Mushroom poisonings are almost always caused by ingestion of wild mushrooms that have been collected by nonspecialists (although specialists have also been poisoned). Most cases occur when toxic species are confused with edible species, and a useful question to ask of the victims or their mushroom-picking benefactors is the identity of the mushroom they thought they were picking. In the absence of a well- preserved specimen, the answer to this question could narrow the possible suspects considerably. Intoxication has also occurred when reliance was placed on some folk method of distinguishing poisonous and safe species. Outbreaks have occurred after ingestion of fresh, raw mushrooms, stir-fried mushrooms, home-canned mushrooms, mushrooms cooked in tomato sauce (which rendered the sauce itself toxic, even when no mushrooms were consumed), and mushrooms that were blanched and frozen at home. Cases of poisoning by home-canned and frozen mushrooms are especially insidious because a single outbreak may easily become a multiple outbreak when the preserved toadstools are carried to another location and consumed at another time.
Specific cases of mistaken mushroom identity appears frequently. The Early False Morel Gyromitra esculenta is easily confused with the true Morel Morchella esculenta, and poisonings have occurred after consumption of fresh or cooked Gyromitra. Gyromitra poisonings have also occurred after ingestion of commercially available "morels" contaminated with G. esculenta. The commercial sources for these fungi (which have not yet been successfully cultivated on a large scale) are field collection of wild morels by semiprofessionals. Cultivated commercial mushrooms of whatever species are almost never implicated in poisoning outbreaks unless there are associated problems such as improper canning (which lead to bacterial food poisoning). A short list of the mushrooms responsible for serious poisonings and the edible mushrooms with which they are confused is presented in Table 3. Producers of mild gastroenteritis are too numerous to list here, but include members of many of the most abundant genera, including Agaricus, Boletus, Lactarius, Russula, Tricholoma, Coprinus, Pluteus, and others. The Inky Cap Mushroom (Coprinus atrimentarius) is considered both edible and delicious, and only the unwary who consume alcohol after eating this mushroom need be concerned. Some other members of the genus Coprinus (Shaggy Mane, C. comatus; Glistening Inky Cap, C. micaceus, and others) and some of the larger members of the Lepiota family such as the Parasol Mushroom (Leucocoprinus procera) do not contain coprine and do not cause this effect. The potentially deadly Sorrel Webcap Mushroom (Cortinarius orellanus) is not easily distinguished from nonpoisonous webcaps belonging to the same distinctive genus, and all should be avoided.
Most of the psychotropic mushrooms (Inocybe spp., Conocybe spp., Paneolus spp., Pluteus spp.) are in general appearance small, brown, and leathery (the so-called "Little Brown Mushrooms" or LBMs) and relatively unattractive from a culinary standpoint. The Sweat Mushroom (Clitocybe dealbata) and the Smoothcap Mushroom (Psilocybe cubensis) are small, white, and leathery. These small, unattractive mushrooms are distinctive, fairly unappetizing, and not easily confused with the fleshier fungi normally considered edible. Intoxications associated with them are less likely to be accidental, although both C. dealbata and Paneolus foenisicii have been found growing in the same fairy ring area as the edible (and choice) Fairy Ring Mushroom (Marasmius oreades) and the Honey Mushroom (Armillariella mellea), and have been consumed when the picker has not carefully examined every mushroom picked from the ring. Psychotropic mushrooms, which are larger and therefore more easily confused with edible mushrooms, include the Showy Flamecap or Big Laughing Mushroom (Gymnopilus spectabilis), which has been mistaken for Chanterelles (Cantharellus spp.) and for Gymnopilus ventricosus found growing on wood of conifers in western North America. The Fly Agaric (Amanita muscaria) and Panthercap (Amanita pantherina) mushrooms are large, fleshy, and colorful. Yellowish cap colors on some varieties of the Fly Agaric and the Panthercap are similar to the edible Caesar's Mushroom (Amanita caesarea), which is considered a delicacy in Italy. Another edible yellow capped mushroom occasionally confused with yellow A. muscaria and A. pantherina varieties are the Yellow Blusher (Amanita flavorubens). Orange to yellow-orange A. muscaria and A. pantherina may also be confused with the Blusher (Amanita rubescens) and the Honey Mushroom (Armillariella mellea). White to pale forms of A. muscaria may be confused with edible field mushrooms (Agaricus spp.). Young (button stage) specimens of A. muscaria have also been confused with puffballs.
Relative Frequency of Disease
Accurate figures on the relative frequency of mushroom poisonings are difficult to obtain. For the 5-year period between 1976 and 1981, 16 outbreaks involving 44 cases were reported to the Centers for Disease Control in Atlanta (Rattanvilay et al. MMWR 31(21): 287-288, 1982). The number of unreported cases is, of course, unknown. Cases are sporadic and large outbreaks are rare. Poisonings tend to be grouped in the spring and fall when most mushroom species are at the height of their fruiting stage. While the actual incidence appears to be very low, the potential exists for grave problems. Poisonous mushrooms are not limited in distribution as are other poisonous organisms (such as dinoflagellates). Intoxications may occur at any time and place, with dangerous species occurring in habitats ranging from urban lawns to deep woods. As Americans become more adventurous in their mushroom collection and consumption, poisonings are likely to increase.
Course of Disease and Complications
The normal course of the disease varies with the dose and the mushroom species eaten. Each poisonous species contains one or more toxic compounds which are unique to few other species. Therefore, cases of mushroom poisonings generally do not resembles each other unless they are caused by the same or very closely related mushroom species. Almost all mushroom poisonings may be grouped in one of the categories outlined above.
Several mushroom species, including the Death Cap or Destroying Angel (Amanita phalloides, A. virosa), the Fool's Mushroom (A. verna) and several of their relatives, along with the Autumn Skullcap (Galerina autumnalis) and some of its relatives, produce a family of cyclic octapeptides called amanitins. Poisoning by the amanitins is characterized by a long latent period (range 6-48 hours, average 6-15 hours) during which the patient shows no symptoms. Symptoms appear at the end of the latent period in the form of sudden, severe seizures of abdominal pain, persistent vomiting and watery diarrhea, extreme thirst, and lack of urine production. If this early phase is survived, the patient may appear to recover for a short time, but this period will generally be followed by a rapid and severe loss of strength, prostration, and pain-caused restlessness. Death in 50-90% of the cases from progressive and irreversible liver, kidney, cardiac, and skeletal muscle damage may follow within 48 hours (large dose), but the disease more typically lasts 6 to 8 days in adults and 4 to 6 days in children. Two or three days after the onset of the later phase, jaundice, cyanosis, and coldness of the skin occur. Death usually follows a period of coma and occasionally convulsions. If recovery occurs, it generally requires at least a month and is accompanied by enlargement of the liver. Autopsy will usually reveal fatty degeneration and necrosis of the liver and kidney.
All humans are susceptible to mushroom toxins. The poisonous species are ubiquitous, and geographical restrictions on types of poisoning that may occur in one location do not exist (except for some of the hallucinogenic LBMs, which occur primarily in the American southwest and southeast). Individual specimens of poisonous mushrooms are also characterized by individual variations in toxin content based on genetics, geographic location, and growing conditions. Intoxications may thus be more or less serious, depending not on the number of mushrooms consumed, but on the dose of toxin delivered. In addition, although most cases of poisoning by higher plants occur in children, toxic mushrooms are consumed most often by adults. Occasional accidental mushroom poisonings of children and pets have been reported, but adults are more likely to actively search for and consume wild mushrooms for culinary purposes. Children are more seriously affected by the normally nonlethal toxins than are adults and are more likely to suffer very serious consequences from ingestion of relatively smaller doses. Adults who consume mushrooms are also more likely to recall what was eaten and when, and are able to describe their symptoms more accurately than are children. Very old, very young, and debilitated persons of both sexes are more likely to become seriously ill from all types of mushroom poisoning, even those types which are generally considered to be mild.
Many idiosyncratic adverse reactions to mushrooms have been reported. Some mushrooms cause certain people to become violently ill, while not affecting others who consumed part of the same mushroom cap. Factors such as age, sex, and general health of the consumer do not seem to be reliable predictors of these reactions, and they have been attributed to allergic or hypersensitivity reactions and to inherited inability of the unfortunate victim to metabolize certain unusual fungal constituents (such as the uncommon sugar, trehalose). These reactions are probably not true poisonings as the general population does not seem to be affected.
The mushroom toxins can with difficulty be recovered from poisonous fungi, cooking water, stomach contents, serum, and urine. Procedures for extraction and quantitation are generally elaborate and time-consuming, and the patient will in most cases have recovered by the time an analysis is made on the basis of toxin chemistry. The exact chemical natures of most of the toxins that produce milder symptoms are unknown. Chromatographic techniques (TLC, GLC, HPLC) exist for the amanitins, orellanine, muscimol/ibotenic acid, psilocybin, muscarine, and the gyromitrins. The amanitins may also be determined by commercially available 3H-RIA kits. The most reliable means of diagnosing a mushroom poisoning remains botanical identification of the fungus that was eaten. An accurate pre-ingestion determination of species will also prevent accidental poisoning in 100% of cases. Accurate post-ingestion analyses for specific toxins when no botanical identification is possible may be essential only in cases of suspected poisoning by the deadly Amanitas, since prompt and aggressive therapy (including lavage, activated charcoal, and plasmapheresis) can greatly reduce the mortality rate.
Isolated cases of mushroom poisoning have occurred throughout the continental United States.
The popular interest in gathering and eating uncultivated mushrooms has been associated with an increase in incidents of serious mushroom-related poisonings. From December 28, 1996, through January 6, 1997, nine persons in northern California required hospitalization after eating Amanita phalloides (i.e., "death cap") mushrooms; two of these persons died. Risks associated with eating these mushrooms result from a potent hepatotoxin. This report describes four cases of A. phalloides poisoning in patients admitted to a regional referral hospital in northern California during January 1997 and underscores that wild mushrooms should not be eaten unless identified as nonpoisonous by a mushroom expert.
Another one occurred in Oregon in October,1988, and involved the intoxication of five people who consumed stir-fried Amanita phalloides. The poisonings were severe, and at this writing three of the five people had undergone liver transplants for treatment of amanitin-induced liver failure.
Other cases have included the July, 1986, poisoning of a family in Philadelphia, by Chlorophyllum molybdites; the September, 1987, intoxication of seven men in Bucks County, PA, by spaghetti sauce which contained Jack O'Lantern mushroom (Omphalotus illudens); and of 14 teenage campers in Maryland by the same species (July, 1987). A report of a North Carolina outbreak of poisoning by False Morel (Gyromitra spp.) appeared in 1986. A 1985 report details a case of Chlorophyllum molybdites which occurred in Arkansas; a fatal poisoning case caused by an amanitin containing Lepiota was described in 1986.
In 1981, two Berks County, PA, people were poisoned (one fatally) after ingesting Amanita phalloides, while in the same year, seven Laotian refugees living in California were poisoned by Russula spp.
An outbreak of gastroenterititis during a banquet for 482 people in Vancouver, British Columbia, was reported by the Vancouver Health Department in June, 1991. Seventy-seven of the guests reported symptoms consisting of early onset nausea (15-30 min), diarrhea (20 min-13 h), vomiting (20-60 min), cramps and bloated feeling. Other symptoms included feeling warm, clamminess, numbness of the tongue and extreme thirst along with two cases of hive-like rash with onset of 3-7 days. Bacteriological tests were negative. This intoxication merits special attention because it involved consumption of species normally considered not only edible but choice. The fungi involved were the morels Morchella esculenta and M. elata (M. angusticeps), which were prepared in a marinade and consumed raw. The symptoms were severe but not life threatening. Scattered reports of intoxications by these species and M. conica have appeared in anecodotal reports for many years.
Numerous other cases exist; however, the cases that appear in the literature tend to be the serious poisonings such as those causing more severe gastrointestinal symptoms, psychotropic reactions, and severe organ damage (deadly Amanita). Mild intoxications are probably grossly underreported, because of the lack of severity of symptoms and the unlikeliness of a hospital admission.
Katja Schulz added an association between "Mushroom Poisoning" and "Galerina autumnalis (Peck) A. H. Sm. & Singer 1964". |
RRS James Clark Ross Cruise JR244 to the southern Weddell Sea
British Antarctic Survey scientists on this cruise are carrying out marine geological and geophysical studies to determine the long-term history of the Antarctic Ice Sheet and climate in the southern Weddell Sea.
The map shows the track of RRS James Clark Ross from the Falkland Islands to the southern Weddell Sea. The yellow oval outlines the main study area. Red dots mark BAS research stations. The area shaded in blue is mostly covered by sea ice.
Specific questions that we are aiming to answer through work on this cruise include:
- how far the Antarctic Ice Sheet advanced onto the continental shelf in this region
during the last glacial period (about 20,000 years ago).
- the history of glacial retreat as the climate warmed after the last glacial period.
- what processes occurred beneath the ice that enabled it to flow across the shelf,
and how the type of material at the sea floor (e.g. hard rock or soft sediment) affected these processes.
- whether or not the ice sheet on West Antarctica collapsed during previous interglacial periods, which have occurred at intervals of about 100,000 years over the past 800,000 years. There is particular concern about the stability of the West Antarctic Ice Sheet because most of its bed is below sea level. If this ice sheet did collapse it would have caused global sea level to rise by more than 3 m.
- how the ocean temperature and sea ice cover in the region have changed during glacial-interglacial cycles, and in particular since the last glacial period.
The results of these studies will be used to test and refine computer models of ice sheets that will be used to predict how much the Antarctic Ice Sheet will contribute to sea level rise in a warming climate.
The main tools being used for this research are coring devices that collect sediments from the sea floor. A gravity corer is used to collect sediments that have accumulated over many thousands of years. In some places where sediment has accumulated more slowly gravity cores contain records that extend back hundreds of thousands of years.
The picture above shows the gravity being recovered in the Weddell Sea.
Mud smeared along the outside of the core barrels shows how far the corer penetrated into the sea floor.
A box corer is used to sample soft surface sediments, which may be disturbed by the gravity corer. Box core samples show what sort of sediments have accumulated under recent conditions.
The picture above shows the box corer being recovered earlier during the cruise, near the South Orkney Islands.
Sophisticated sonar devices are being used to map the shape of the sea floor and the thickness of soft sediments. The results of these surveys are essential for selecting the best core sites. The sonar data also provide a lot of information about the pattern of ice flow and the processes that operated beneath the ice when it advanced onto the shelf.
The ship’s multibeam echo sounder reveals the water depth and the shape of the sea floor over a zone up to four times as wide as the water depth under the ship, as illustrated in the picture below. It transmits 191 narrow beams of high frequency sound (near the upper limit of the frequency range detectable to the human ear) from the bottom of the ship and detects the echoes from the sea floor.
A sub-bottom acoustic profiler is used to show the thickness of soft sediments beneath the sea floor and the layering within them. It transmits intermediate frequency sound pulses (quite high-pitched to the human ear) from the bottom of the ship and detects the echoes from the sea-floor and soft sediment layers beneath the sea floor.
The image below shows an example of part of a sub-bottom profile.
The sub-bottom profiler only “sees” through very soft muddy sediments. Even some relatively young glacial sediments cannot be imaged with this device. For this reason we sometimes need a way of looking through harder sediments or sedimentary rocks to find out what is beneath the sea floor and understand the origin of sediment deposits. On this cruise we are occasionally using a small seismic reflection profiling system consisting a single “airgun” and a short “hydrophone streamer”. The airgun is towed behind the ship and creates a low frequency sound signal (in the range of the bass notes on a musical instrument) by releasing a burst of high pressure air into the water. The hydrophone streamer, which is also towed behind the ship, detects the sound reflected from the sea floor and boundaries between layers of sedimentary rocks beneath the sea floor.
The picture below shows the seismic airgun being deployed over the stern of the ship. |
Although vegetarian diets are typically defined by the exclusion of meat and other flesh foods, a healthy vegetarian diet is one in which a variety and abundance of plant-based foods are primarily consumed. Animal products such as dairy and eggs may be selectively consumed in varying amounts or not at all. Plant foods include: grains, legumes (including soy foods), vegetables, fruits, nuts, seeds, plant oils, herbs and spices, and plant-based beverages. A variety of foods from all plant food groups consumed daily in adequate quantities will provide all of the recommended nutrients (except for vitamin B12), fiber, and other substances needed.
In the past, unrefined foods have been emphasized because they contained more vitamins and minerals. The food industry has effectively refined and processed foods to the point where some foods must be enriched or fortified in order to replace some of the lost nutrients. While these foods are part of most diets, lesser-refined plant foods provide additional micronutrients, fiber, and various antioxidants and phytochemicals. More and more is being discovered concerning the importance of these food substances to physiological function, as well as the amount and balance needed for optimal health.
Although vegetables, fruits, nuts, and legumes are often consumed with minimal refinement, this is not the case for foods made from grains. However, whole-grain foods are more likely to decrease risk of heart disease, some cancers, and diabetes, while refined-grain foods do not appear to carry these same benefits. A diet based on unrefined and minimally processed foods is more likely to supply the quantities and proportions of substances deemed safe and adequate that will also promote optimal health.
Vegetarians who base their diets entirely on plant foods should take care in selecting foods to meet their nutritional needs. This is especially true for growing children, pregnant and lactating women, and the elderly. Vegetarian diets which include dairy foods and/or eggs provide all the nutrients needed, and have been shown to be healthful in a variety of populations. Since some dairy products are high in saturated fat, it is preferable to consume small amounts of these and to emphasize nonfat and low-fat products.
Plant foods are naturally devoid of vitamin B12, and individuals who avoid dairy products and/or eggs need a regular and reliable source of this vitamin, such as B12-fortified breakfast cereals, vegetable protein products and milk alternatives, or a vitamin preparation.
Although leafy and green vegetables are rich sources of calcium, consuming these foods in amounts adequate to meet the needs of some individuals may present a problem. Other calcium-rich plant food items which may be emphasized are tofu (made with calcium sulfate), calcium-fortified fruit juices and milk alternatives, some nuts, and dried fruits.
In the United States, the principal dietary source of vitamin D is milk, fortified with this vitamin. Diets which exclude milk, including those that are based entirely on plant foods, may require a supplementary source of vitamin D in the absence of adequate sunlight exposure. This is likely to occur in latitudes farther from the equator and during the winter months. Examples of vitamin D-fortified plant foods are some breakfast cereals and milk alternatives.
Many equate vegetarian diets with low-fat diets. Very low-fat vegetarian diets have proven helpful in therapeutic approaches to several disease conditions; thus, some individuals advocate low-fat vegetarian diets for everyone. Although it is easier to design a diet very low in both total and saturated fat in the context of a vegetarian diet, this should not imply that most vegetarians consume a low-fat diet. The average total fat intake of vegetarians varies widely (15 to 40 percent of daily energy) and the whole range of fat intake is compatible with excellent health.
Unrefined plant sources of fat, such as nuts, seeds, avocados, and olives are generously consumed by some vegetarians and not as much by others. These foods are sources of unsaturated fats, as well as antioxidants, phytochemicals, and dietary fiber. According to surveys, vegetarians consume more nuts more frequently than non-vegetarians. This is not a recent or local phenomenon. In India, with a millennium of vegetarian tradition, peanuts and peanut oils are a prominent part of the diet. Studies of vegetarians in the West during the first half of this century show that nuts provided 6 to 15 percent of the daily calories. Vegetarian Seventh-day Adventists in California eat nuts more frequently than their non-vegetarian counterparts, and much more than the general population.
The Adventist Health Study reports that men and women consuming nuts four or more times a week lowered their risk of heart disease by 50 percent and increased life expectancy by several years, as compared to those who hardly ever ate nuts. Experimental trials show that specific nuts lower blood lipids, and similar beneficial effects have been described for olive oil, avocados, and other unrefined plant-fat sources. Incorporating these foods in the diet may increase fat in the diet, but also contributes texture, aroma, and flavor.
Hydrogenated vegetable oils, such as are contained in margarines, shortening, and many commercial bakery products and snack foods, may have detrimental health effects and should be avoided. Tropical oils (coconut, palm kernel, and palm oils) are high in saturated fat and should be limited.
Currently, public health recommendations for total fat in the diet suggest keeping fat intake below 30 percent of the total energy (calories), based on data from Western populations where a major portion of dietary fat comes from eating animal foods and fat, as well as highly processed snack-type fatty foods. It is not clear if the same recommendations apply to vegetarians whose dietary fat comes mostly from unrefined plant food sources.
Fluid intake among vegetarians is higher than the general population. Some vegetarians drink as much as two to three liters of fluid a day, including water, freshly prepared fruit and vegetable juices, a variety of hot teas, and soups. Excluding water, these examples may represent an additional source of micronutrients and phytochemicals in the diet. A generous fluid intake is useful in treating several diseases and there is some research on the health-promoting effects and specific disease prevention of such a lifestyle characteristic.
Individuals choosing to follow a vegetarian diet often choose additional healthy lifestyle habits such as regular physical exercise, frequent exposure to sunlight, and fresh air. These are all factors considered essential to achieving and maintaining optimal nutrition and a healthy body weight.
Sufficient skin exposure to sunlight produces an adequate amount of vitamin D. In the absence of frequent sunlight exposure, vitamin D becomes an important nutritional factor and a dietary requirement. Nutrition sources include fortified foods such as cereals and dairy.
Daily exposure to fresh air and outdoor activities is also desirable and may have an added mental--as well as physical-- benefit. The Surgeon General recommends that all adults participate in regular, daily physical activity that is aerobic in nature and promotes fitness and well-being. Physical activity should be balanced with energy intake to ensure a healthy body weight.
Loma Linda University Authors
Joan Sabaté, MD, DrPH, associate professor and chair of nutrition, School of Public Health
Ella Haddad, DrPH, RD, associate professor of nutrition, School of Public Health
Crystal Whitten, MS, RD, assistant professor of nutrition and dietetics, School of Allied Health Professions
Larry Kidder, MA, editor, University relations office
The following persons have been instrumental in providing feedback and guidance in the preparation of this document.
John Anderson, University of North Carolina, Chapel Hill, North Carolina, USA
Diane Butler, Sanitarium Health Food Company, Sidney, Australia
Winston Craig, Andrews University, Berrien Springs, Michigan, USA
Suzanne Havala, The Vegetarian Resource Group, Baltimore, Maryland, USA
Tim Key, Imperial Cancer Research Fund, University of Oxford, Oxford, England, UK
Lawrence Kushi, University of Minnesota, Minneapolis, Minnesota, USA
Mark Messina, Nutrition Matters, Inc., Port Townsend, Washington, USA
David Nieman, Appalachian State University, North Carolina, USA
Helen Roe, Preventive Medicine Research Center, Sausalito, California, USA
Walter Willett, Harvard University, Boston, Massachusetts, USA |
Scientists have known for decades that the genomes of animals can sometimes harbor DNA from the viruses that have infected them. When I first learned of this fact some years ago, it blew my mind. The notion that any animal could be a little bit viral blurred nature’s boundaries.
The viruses that scientists discovered in host genomes were of a particular sort, known as endogenous retroviruses. Retroviruses, which include HIV and a number of viruses that can trigger cancer, have to insert their genetic material into their host’s genome in order to reproduce. The cell reads their genetic instructions along with its own, and then builds new viruses. It made a certain intuitive sense that retroviruses might sometimes get trapped in their host genomes, to be passed down from one generation to the next.
The first endogenous retroviruses scientists identified were still relatively functional. Under certain circumstances, their genes could still give rise to new viruses that could break out of their host cell. But gradually, scientists identified more and more fossil viruses, which had mutated so much that they could no longer reproduce. As I wrote in the New York Times in 2006, scientists have even figured out how to resurrect these fossil viruses from the human genome.
That would have been weird enough. But nature is generous with its weirdness. As I wrote in the Times earlier this year, scientists have started finding viral stretches of DNA in our genomes that are not retroviruses. In that article, I focused on the discovery of genes from bornaviruses, which just park themselves next to our DNA, rather than inserting their genes into our own.
New kinds of endogenous viruses keep turning up as scientists looked closer. Today in the journal PLOS Genetics, Aris Katzourakis of the University of Oxford and Robert Gifford of New York University offer a particularly startling survey of the viral world within. Rather than searching for one particular kind of virus, they hunted for a wide range of them. Their collection reflected all the different ways that viruses can replicate inside mammal cells. They then hunted for the sequences of these viruses in the genomes of 44 mammal species, plus a handful of birds and invertebrates. The scientists struck viral gold. Every major group of viruses turned up in the host genomes.
In most cases, the viruses infected their own host. But the scientists also found mammal viruses integrated into the genomes of ticks and mosquitoes–perhaps as a result of their feeding on virus-infected mammal blood. In many cases, viruses slipped into their host genomes a long, long time ago. The scientists discovered segments of bornavirus present not just in humans, but in monkeys from the Old World and New World. We share a common ancestor with monkeys that lived some 54 million years ago. What’s more, one of these bornavirus segments is very similar in many of its hosts today. That uniformity suggests that it has taken on a useful function in our own bodies. Scientists have already found evidence that endogenous viruses can help build placentas and fight off other viruses; now bornaviruses can be added to the list.
This is one of those exploding fields that is a joy to follow. I’m glad that this new paper came out before I had to turn in my proofs for my next book, called A Planet of Viruses, which will be coming out in May. But I’m sure that the catalog of inner viruses will be growing a lot longer in years to come. |
Perspectives on the Gunpowder Incident
On the evening of April 20, 1775, Lord Dunmore, Governor of Virginia, sent twenty British sailors under the command of Lieutenant Henry Collins to remove all of the gunpowder from the public magazine in Williamsburg. The townspeople sounded the alarm, but not before Collins and his sailors got away with 15 barrels of gunpowder. An angry mob threatened to burn down the palace, but was talked down by Peyton Randolph. Dunmore explained that he confiscated the powder because of fears of a slave uprising; however, colonists suspected that he wanted to put down a potential rebellion against the British colonial government. Soon after this incident, Dunmore issued a proclamation promising to free all slaves who were owned by rebels and were willing to take up arms for the British.
In this lesson, students will examine the Gunpowder Incident from the perspectives of five different historical characters. They will work in small discussion groups to consider and defend their characters' actions during the episode. Students will then present their characters' point of view to the class and take notes on each others' presentations. Those notes will be used to help students as they draw comic strips depicting what they think really motivated the Gunpowder Incident.
- Feature article: Mary Miley Theobald, "The Monstrous Absurdity," Colonial Williamsburg Journal, (Summer 2006) 1-5
- Biographies sheet
- Note taking handout
- Blank sheets of paper
- Colored pencils
- Magazine Exterior Image (for lesson extension)
- Magazine Diagram (for lesson extension)
- Read the introduction describing the Gunpowder Incident out loud to the class. Provide additional information from the feature article as needed.
- Divide the students into five groups. Provide each group with a brief biography of one of the five individuals involved in the Gunpowder Incident: Lord Dunmore, Governor of Virginia, Peyton Randolph, Speaker of the Virginia House of Burgesses, Patrick Henry, a Patriot leader, Joseph, a slave, and Robert Mackey, a townsperson from Williamsburg (Joseph and Robert's characters are fictional).
- Have students review the descriptions of their characters to gain knowledge about their backgrounds, motives, perspectives, and actions during the Gunpowder Incident. (You may need to define "motive" and "perspective" for students.) Discussing their character in small groups will help students draw conclusions and enable them to better share their findings with the class.
- Explain to the class that not all of the answers to the questions will be in the biography cards. They will have to make inferencesguesses based on factsabout what their character was thinking or feeling at the time.
- Each group is to present their character to the class. They should speak in character and explain what actions the individual took and why he felt it was the best course of action considering his background, motives, and perspective.
- As each group makes its presentation, the remaining students should take notes on the information presented.
- Have students draw a comic strip titled "What I Think Happened at the Gunpowder Incident." They can draw their strip from the perspective of any of the characters discussed in class, and should use their notes to inform their choices.
- Post the completed comic strips around the room so students can see each other's work.
- Once students have had a chance to view the comic strips, summarize the incident with the class and discuss the outcome of the affair.
- Provide students with information about the Lexington and Concord gunpowder incident. Have students complete a Venn diagram comparing and contrasting the two incidents.
- Project the Magazine Exterior Image and the Magazine Diagram for the class. Point out the following features, and ask the class to come up with reasons why each of these is beneficial for a powder magazine:
- surrounded by a wall
- far from adjacent buildings
- made of brick
- weapons on upper floors of a tall, thin structure
- narrow stairs
- few windows
This lesson was written by Marinanne Esposito, Key West, FL, and Kim O'Neil, Liverpool, NY. |
What is vertigo?
Vertigo is a symptom in which you feel as if you are moving, spinning or floating, even if you are stationary. Vertigo is often accompanied by other symptoms, such as dizziness, impaired balance, lightheadedness, and nausea. It is estimated that four out of ten Americans may have an episode of vertigo and seek medical attention (Source: NIH).
There are two main types of vertigo, peripheral and central. Peripheral vertigo affects the vestibular system, which includes the inner ear and vestibular nerve and controls balance. Central vertigo is the result of a problem related to the brain.
There are many causes of both types of vertigo, including medication side effects, infection, disorders, and injuries. In some cases, there is no known cause of vertigo. Vertigo may begin or end suddenly, or gradually worsen over time. Vertigo may be temporary or long-term, depending on the underlying cause.
Vertigo may be a symptom of serious or life-threatening condition, such as a traumatic brain injury. Seek immediate medical care (call 911) if you have vertigo and other serious symptoms, such as changes in consciousness, vomiting, severe headache, and abnormal behavior.
Seek prompt medical care if your vertigo is persistent or causes you concern.
What other symptoms might occur with vertigo?
Vertigo may accompany other symptoms, which vary depending on the underlying disease, disorder or condition. Symptoms that frequently affect the vestibular system may also involve other body systems.
Common symptoms that may occur along with vertigoOften, vertigo may accompany other symptoms including:
- Blurred or double vision
- Dizz... Read more about vertigosymptoms
What causes vertigo?
There are two main types of vertigo, peripheral vertigo and central
vertigo. Peripheral vertigo occurs as the result of a problem with the
vestibular system, which includes the inner ear and vestibular nerve and
controls balance. Central vertigo is the result of a problem related to
the brain. In many cases, the precise cause of vertigo is not |
In 1915 Einstein predicted that spacetime can be warped: the flow of time slows near a massive body (a planet, star, or black hole); the circumference of a massive body is smaller than π times its diameter; and as it spins, a massive body drags the nearby space into a tornado-like whirl.
Einstein's predictions were almost solely of academic interest until 1975, when human technology became sophisticated enough to test them with high precision. Since then, many experiments and observations have verified the warping of spacetime in our solar system and in binary pulsars, to high accuracy.
Just as human technology was inadequate for precision tests of relativity until about 1975, so our theoretical tools were inadequate for deducing general relativity s predictions — with a few exceptions — until about 1965. From 1965 into the 1980s, Stephen Hawking, Roger Penrose, Kip Thorne, and others used new theory tools to generate a golden age of relativity research — a revolution in our understanding of warped spacetime. Among their discoveries were these:
This astonishing period of progress ended, however, in the 1980s. Theoretical research in Relativity hit a brick wall, as theoretical tools neared the limits of their capabilities. Progress in understanding relativity's predictions was slowing to a crawl, while physicists were convinced that they had only begun to plumb Einstein's theory. They had discovered the nature of black holes, and had seen how those holes behave when slightly disturbed, but their tools were too weak to probe the wildly nonlinear oscillations of warped spacetime triggered by colliding black holes. This scenario of two black holes colliding has proven to be an extremely interesting problem, as well as an overwhelmingly difficult one.
Imagine a pair of black holes alone in space. As each one spins, it drags the spacetime around it into a tornado-like whirl. As the pair orbit around each other, the holes' orbital angular momentum creates a third, larger whirl. What happens when two tornadoes, embedded in a third larger tornado, come crashing together and the tornadoes are made from whirling space, not whirling air? We have almost no idea. It is as though we had briefly glimpsed the surface of the ocean on a calm day (an analog to a quiescent or weakly vibrating black hole), but we had never seen the stormy sea, nor breaking ocean waves, nor water spouts.
Physicists wondered what other kinds of phenomena can be produced by warped spacetime, besides quiescent and weakly vibrating black holes. How does the singularity inside a black hole behave when the hole is newborn, with its space and time stormy? Can there exist naked singularities, unclothed by horizons, opened up for the universe to see? What other huge surprises lurk in Einstein's equations, yet to be discovered? The answers will transform our understanding of space and time in remarkable ways.
Physicists have begun to take a two-pronged approach to the difficulties presented by In the late 1970s, as the brick wall began looming up before them, physicists became convinced that they can unlock Einstein's remaining mysteries by a new, two-pronged attack. The first prong is theoretical: the numerical solution of Einstein's equations using supercomputers (Numerical Relativity), leading to simulations of warped spacetime that reach into the rich domains that our previous tools could not touch. The second prong is experimental: observational studies of gravitational waves from colliding black holes and other phenomena where spacetime is highly warped the 'warped side of our universe'. They also realized that the two prongs were complementary and must work together:
In the late 1970s, gravitational-wave detection seemed a greater challenge than numerical relativity, so scientists initiated a wave-detection program. Their efforts have given rise to the Laser Interferometer Gravitational Wave Observatory (LIGO), and its lower-frequency, space-based cousin, the NASA-ESA Laser Interferometer Space Antenna (LISA). LIGO is now operating near its design sensitivity and could detect waves from black holes this year. NSF has recently approved funding to upgrade the LIGO detectors near the end of this decade, bringing us to a sensitivity where we are confident of seeing a large number and wide variety of waves. LISA will be launched a few years after the LIGO upgrade. Scientists are now contemplating the follow-on to LISA.
Much to the dismay of the physicists who originally laid out the groundwork for these investigations, numerical relativity has matured more slowly than gravitational wave detection. It is a far more difficult enterprise than they had thought in the 1970s, and the resources devoted to it have been woefully inadequate. The goal of the SXS project is to correct this problem, and to open the door to the new and exciting physics encoded in gravitational waves. |
This mosaic of Jupiter's ring system was acquired by NASA's Galileo spacecraft when the Sun was behind the planet, and the spacecraft was in Jupiter's shadow peering back toward the Sun.
In such a configuration, very small dust-sized particles are accentuated so both the ring particles and the smallest particles in the upper atmosphere of Jupiter are highlighted. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.
Jupiter's ring system is composed of three parts: a flat main ring, a toroidal halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. Only the main ring and a hint of the surrounding halo can be seen in this mosaic. In order to see the less dense components (the outer halo and gossamer ring) the images must be overexposed with respect to the main ring.
This composite of two mosaics was taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system on November 9, 1996, during Galileo's third orbit of Jupiter. The ring was approximately 2,300,000 kilometers away. The resolution is approximately 46 kilometers per picture element from right to left; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The vertical bright arcs in the middle of the ring mosaics show the edges of Jupiter and are composed of images obtained by NASA's Voyager spacecraft in 1979.
The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC.
This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URLhttp://www.jpl.nasa.gov/galileo/sepo |
CSS2 and RGB
The RGB color system is an additive model in which red, green, and blue are combined in various ways to reproduce other colors. The RGB system was formally introduced in HTML3.2 and CSS1, but was used in HTML versions before that as well.
CSS2 has five ways of interpreting RGB colors:
- using a full hex combination:
- using a shorthand hex combination:
- using a comma-separated list of three numerical integer values:
rgb(255, 0, 0)
- using a comma-separated list of three numerical percentage values:
rgb(100%, 0%, 0%)
- using a color keyword (sometimes referred as named color), f ex
The shorthand hex notation is arguably most popular since it’s shorter and possibly easier to remember. It is worth noting that the so called web safe color palette persists of 216 combinations using the shorthand hex combination in steps of three, f ex #000 #333 #99C #F93 etc. Calling it “web safe” can be confusing though, since it’s origin is from the old days of limited video hardware that had a smaller range of 216 RGB colors. “Screen safe” might be a more appropriate definition. However, almost every display uses 24-bit RGB and 16.7 million RGB colors these days, and therefore it is probably “web safe” to use any RGB combination from the full spectra today.
HTML4 officially supports 16 named colors, but it has been a fact over the last few years that almost all major browsers supports 140 named colors.
The CSS3 Color Model
CSS3 supports a wider range of color definitions and the most important new feature is HSL support. The HSL color model stands for Hue, Saturation and Lightness / Intensity and is a non-linear deformation of the RGB colour system. It does not include a wider or more limited range of colors, it is simply a more human way to code colors than RGB ever was. The Hue is defined using an angular integer ranging from 0 to 360 degrees. This represent a base color from the HSL cone ranging from red (0°) to green (120°) to blue (240°) and then back to red. Saturation and lightness is defined using percentages from 0 – 100% and complements the hue to create the full color. So for example, if I have a bright blue base color like this:
hsl(240, 100%, 50%);
We can simply adjust the two percentages to make it less or more saturated/darkened.
Basically all graphic software are using HSL or the similar HSV and its fundamental simplicity makes it much more sensible for a human to understand and adapt. Just pick a color using the wheel, then adjust it’s subtleness, instead of crazy hex values and additive integers.
Here is a simple reference list for HSL values to create basic colors, with a 60 degrees interval. Memorize this and you can produce almost any color just by adjusting the numbers slightly:
- 0 – red
- 60 – yellow
- 120 – green
- 180 – turquoise
- 240 – blue
- 300 – pink
- 360 – red
In addition to HSL, CSS3 also introduces
hsla. It is basically the same as
hsl, except that it also includes a fourth integer for opacity (or alpha) ranging from 0 to 1.
That is all for this time about colors in CSS. I hope that you have found this guide to be useful. Try this out in your own project and create beautiful HTML5 pages with the help of your great knowledge in this area. |
Ornamental flowers come in a wide variety of shapes, sizes and colors. Ornamental flowers, as opposed to native wild flowers, are generally not indigenous to local ecosystems, and they require additional care and maintenance. From common to exotic, ornamental flowering plants are the centerpiece of any garden or landscape.
Flowering Maples (Abutilon hybridum) have green foliage and colorful red, yellow, white and orange flowers that blossom mid-summer. Growing 12 to 18 inches in height with a maximum spread of 4 to 5 feet, Flowering Maples prefer moist soil, they are partial to direct sunlight, and they are normally grown indoors as houseplants.
Geraniums (Pelargonium x hortorum) have small green leaves that extend from a multiple stem structure, with bright pink, red and salmon flowers that blossom during the early spring and late fall. Geraniums grow 12 to 24 inches, and they require full sunlight and moist, nutrient-rich soil.
Marigolds (Tagetes erecta) are common ornamental flowers with green foliage and distinctive gold, orange and yellow flowers blooming from late spring through early fall. Marigolds are 8 to 48 inches in height, they require direct sunlight, and they are moderately drought-tolerant.
Petunias (Petunia x hybrida) can grow between 6 and 18 inches in height. They feature green-gray foliage with white, purple, yellow and pink flowers that blossom in the spring and summer. Petunias are hardy ornamental flowers that are drought-tolerant, and they can thrive in full or partial sunlight.
Monkey Flowers (Mimulus x hybridus) are small ornamental plants that grow 1 to 2 feet in height with bright and colorful red, yellow and orange flowers that bloom throughout the summer months. Monkey Flowers prefer full sunlight, and uniformly moist and nutrient-rich, organic soil. They also tolerate cooler overnight summer temperatures. |
Living in a cave full-time requires some extreme survival skills, which is why many cave-dwelling organisms are called extremophiles. Extremophiles are important to Earth Science, because they hold many clues to early life.
The strange names of cave dwellers doesn’t stop with extremophiles … Consider troglobites, troglophiles and trogloxenes!
Colorado is home to more than 15 species of bats, and most can be spotted in the area around our cave. Some bats use caves to give birth and care for their young in the summer. In winter, some bats hibernate, while others migrate. When bats are disturbed in their preferred environment, they often leave for less-protected environments, which contributes to the current decline of bat populations worldwide.
Bats tend to be very misunderstood: they’re not blind, aggressive or prone to flying into your hair. Bats contribute to a healthy ecosystem, because they help keep insects under control, pollinate plants, and are responsible for most new seed dispersal in the rain forests. Most bats in the western United States feed almost exclusively on insects — in fact, bats are the only major predator of night-flying insects. Bats typically eat more than 50% of their body weight in insects each night.
Bats are gentle, intelligent mammals, and the perception of bats as carriers of rabies and other diseases is greatly exaggerated. Fewer than 40 people in the United States are known to have contracted rabies from bats over the past 40 years. Far more people are killed by dog attacks, bee stings or lightening strikes.
Cave of the Winds is proud to promote the benefits of bats and is a supporter of Bat Conservation International. We encourage people to attract bats by placing bat houses in their yards to take advantage of their insect-eating habits.
Insects are common at Cave of the Winds, although they can be hard to spot. Our most famous insect is called the hyperchills benetti. It weaves its web into a shape similar to lampshades (hence its more common name, the Lampshade Spider). One of the most interesting things about them is that they have two sets of lungs that allow them to breathe in oxygen-deprived environments — perfect for caves!
The petite ringtail is a favorite at Cave of the Winds, although it’s nocturnal and good at hiding, so we’re honored with sightings only so often. The ringtail, or basarscus astutus, is a small, slender animal with a long, bushy tail that has black and white bands (thus the “ring tail”). The ringtail is a skilled climber, which is a great skill for cave living. The ringtail eats a varied diet of small mammals, birds, lizards, frogs, insects, snakes, cactus fruits and other plants. It communicates with a bark, scream, snarl, whistle and chitter, although when under stress, they will give an undulating howl.
A host of other native animals use caves when needed. When caving in our area, it’s possible to see large and small birds, including swallows, falcons, hawks, and an occasional eagle. It’s also possible to run into mammals of all sizes — mice, deer, mountain lions and bears. If you see wildlife, it’s always best to keep your distance. For mountain lions, the rule is to make yourself bigger: raise your arms, hold up anything to make yourself appear threatening and impressive. For bears, use the opposite rule: make yourself small and non-threatening. Avoid eye contact with the bear, as this is seen as a challenge. These large animals tend to keep their distance, so more than likely, your visit to our beautiful Rocky Mountain Front Range will be safe and awe-inspiring. |
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1. Read to them.Some parents start reading to their child in the womb! Whether or not it's necessary to start that early might be debatable, but it is important to start reading to your baby early on in infancy. Even the youngest infants will enjoy the sound of your voice as you read to them.
As children grow older they can enjoy the colors, shapes, and pictures. Eventually children will be able to read themselves, but they will still value you taking the time to read to them. After they can read on their own, you can do shared reading time and take turns reading to each other!
2. Read what they like.It's important to recognize that children are more likely to read something that interests them! If you child is into superheroes, Barbie, bugs, horses, etc. then get them books about their topic of interest. If you're not sure, try simply asking your child or just buying a variety of books. You might also consider books with familiar characters or themes.
3. Reward them with reading.Now while rewarding reading is definitely an option, rewarding with reading is a great way to promote that reading is a fun, positive experience. For example, allowing older children to stay up 15 minutes past their bed time, if they're reading, is a way to reward children with reading. Don't assign reading as punishment, as that will only reinforce any ideas your child has that reading is not for fun.
4. Lead by example.Carve out some time in your busy schedule to lead by example, and read for pleasure. If this is not something you typically do, try following tip #2 for yourself.
Remember that there are a variety of types of reading materials. These include magazine, poetry, self help books, how to books, fiction novels, and more. Find what your kids like. Find what you like. And read on!
What are you currently reading or hoping to read? What does your child enjoy reading? |
Autism is a difficult to understand and complex illness commonly diagnosed in childhood. Children with Autism have a wide spectrum of symptoms including struggling with social interactions, understanding language, expressive communication, repetitive/purposeless behaviors, and difficulty establishing relationships with others. While Autism symptoms and severity ranges significantly, untreated Autism can lead to self-harming behaviors, destructive aggression, and serious behavioral outbursts at school.
What Is Autism?
Autism spectrum disorder (ASD) is a complex neurological disorder. Commonly known as autism, the disorder usually manifests in early childhood and affects a child’s ability to communicate and interact with others. Symptoms can include a wide range of social, linguistic, and sensory issues. However, since autism is a spectrum disorder, the symptoms can vary widely. No two children with autism are alike.
How Is Autism Diagnosed?
If your child has developmental delays, you should speak with a health care professional who specializes in neurological or developmental issues in children. NeuroHealth Arlington Heights is an expert family practice that can assess your child. We offer autism treatment to patients in and around Arlington Heights, IL.
Since ASD symptoms vary so widely, diagnosis can be tricky. There isn’t one set test that can determine whether or not your child is on the spectrum. However, working with an experienced medical provider who has worked with many similar cases increases your chances of getting a correct diagnosis.
The specialist may:
- Review your child’s communication, behavior, and social interactions over time.
- Test your child’s understanding of language and social skills.
- Ask your child to interact in a structured social situation and observe how he or she behaves.
- Look into other disorders that have similar symptoms, like fragile X syndrome.
After gathering this information, your specialist may be prepared to give a diagnosis. To be diagnosed with ASD, your child must meet these criteria:
- Experience difficulties with social situations.
- Have trouble understanding nonverbal communication, like body language.
- Have trouble developing and understanding relationships.
Your child must also show at least two of these criteria:
- Repetitive movements or speech patterns
- Extreme distress when routines are interrupted
- Abnormal interest in objects or topics
- Either abnormally high or abnormally low sensitivity to sensory input
If your specialist notices these signs, your child could be diagnosed with autism.
How Is Autism Treated?
ASD is not a curable disorder, and the cause is still unknown in the medical world. Because symptoms vary so widely, there isn’t a set treatment that is guaranteed to work. However, if your child has autism, he or she can still get treatment that will help him or her function and even thrive in society.
Treatment can include behavioral therapy, family therapy, and medication:
- Behavioral therapy helps children understand social situations and linguistic skills. Because children with ASD don’t intuitively grasp social norms, this kind of therapy teaches them how to behave acceptably in different situations and how to communicate with other people.
- Family therapy is focused on helping the child’s entire family. Your family may not know how to successfully interact with your child with autism, and therapy can help your home function smoothly and peacefully.
- Medication isn’t a way to cure ASD. However, certain medicines may help with symptoms. For example, if your child shows severe distress when anything disrupts his or her routine, anti-anxiety medication may help.
NeuroHealth Arlington Heights provides comprehensive treatment for autism, and we can help you find the right treatment for your child’s unique needs.
To learn more about autism treatment in Arlington Heights, IL, come to NeuroHealth. We can evaluate, diagnose, and treat your child to give him or her a better chance at a happy future. Contact us at (847) 754-9343. |
Nitroglycerine is an explosive liquid which was first made by
Ascanio Sobrero in 1846 by treating glycerol with a mixture of
nitric and sulphuric acid. The reaction which follows is highly
exothermic, i.e. it generates heat and will result in an
explosion of nitroglycerine, unless the mixture is cooled while
the reaction is taking place. Liquid nitroglycerine is colorless
if pure. It is soluble in alcohols but insoluble in water.
Nitroglycerine is extremely sensitive to shock and in the early
days, when impure nitroglycerine was used, it was very difficult
to predict under which conditions nitroglycerine would explode.
Alfred Nobel studied these problems in detail, and was the first
to produce nitroglycerine on an industrial scale. His first major
invention was a blasting cap (igniter), a wooden plug filled with
black gunpowder, which could be detonated by lighting a fuse.
This in turn, caused an explosion of the surrounding
Alfred Nobel worked hard to improve nitroglycerine as an explosive that could be used in blasting rock and in mining. He made one of his most important discoveries when he found that by mixing nitroglycerine, an oily fluid, with kieselguhr, the mixture could be turned into a paste. This material could be kneaded and shaped into rods suitable for insertion into drilling holes. He called his paste dynamite and went on to develop a blasting cap which could be used to detonate dynamite under controlled conditions. |
From Wikipedia, the free encyclopedia - View original article
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Wastewater, also written as waste water, is any water that has been adversely affected in quality by anthropogenic influence. Municipal wastewater is usually conveyed in a combined sewer or sanitary sewer, and treated at a wastewater treatment plant. Treated wastewater is discharged into receiving water via an effluent sewer. Wastewaters generated in areas without access to centralized sewer systems rely on on-site wastewater systems. These typically comprise a septic tank, drain field, and optionally an on-site treatment unit.
Sewage is the subset of wastewater that is contaminated with feces or urine, but is often used to mean any wastewater. Sewage includes domestic, municipal, or industrial liquid waste products disposed of, usually via a pipe or sewer (sanitary or combined), sometimes in a cesspool emptier.
Sewerage is the physical infrastructure, including pipes, pumps, screens, channels etc. used to convey sewage from its origin to the point of eventual treatment or disposal. It is found in all types of sewage treatment, with the exception of septic systems, which treat sewage on site.
Wastewater or sewage can come from (text in brackets indicates likely inclusions or contaminants):
The composition of wastewater varies widely. This is a partial list of what it may contain:
Any oxidizable material present in a natural waterway or in an industrial wastewater will be oxidized both by biochemical (bacterial) or chemical processes. The result is that the oxygen content of the water will be decreased. Basically, the reaction for biochemical oxidation may be written as:
Oxygen consumption by reducing chemicals such as sulfides and nitrites is typified as follows:
Since all natural waterways contain bacteria and nutrients, almost any waste compounds introduced into such waterways will initiate biochemical reactions (such as shown above). Those biochemical reactions create what is measured in the laboratory as the biochemical oxygen demand (BOD). Such chemicals are also liable to be broken down using strong oxidizing agents and these chemical reactions create what is measured in the laboratory as the chemical oxygen demand (COD). Both the BOD and COD tests are a measure of the relative oxygen-depletion effect of a waste contaminant. Both have been widely adopted as a measure of pollution effect. The BOD test measures the oxygen demand of biodegradable pollutants whereas the COD test measures the oxygen demand of oxidizable pollutants.
The so-called 5-day BOD measures the amount of oxygen consumed by biochemical oxidation of waste contaminants in a 5-day period. The total amount of oxygen consumed when the biochemical reaction is allowed to proceed to completion is called the Ultimate BOD. Because the Ultimate BOD is so time consuming, the 5-day BOD has been almost universally adopted as a measure of relative pollution effect.
There are also many different COD tests of which the 4-hour COD is probably the most common.
There is no generalized correlation between the 5-day BOD and the ultimate BOD. Similarly there is no generalized correlation between BOD and COD. It is possible to develop such correlations for specific waste contaminants in a specific wastewater stream but such correlations cannot be generalized for use with any other waste contaminants or wastewater streams. This is because the composition of any wastewater stream is different. As an example an effluent consisting of a solution of simple sugars that might discharge from a confectionery factory is likely to have organic components that degrade very quickly. In such a case, the 5 day BOD and the ultimate BOD would be very similar since there would be very little organic material left after 5 days. However a final effluent of a sewage treatment works serving a large industrialised area might have a discharge where the ultimate BOD was much greater than the 5 day BOD because much of the easily degraded material would have been removed in the sewage treatment process and many industrial processes discharge difficult to degrade organic molecules.
The laboratory test procedures for the determining the above oxygen demands are detailed in many standard texts. American versions include the "Standard Methods for the Examination of Water and Wastewater."
In some urban areas, sewage is carried separately in sanitary sewers and runoff from streets is carried in storm drains. Access to either of these is typically through a manhole. During high precipitation periods a sanitary sewer overflow can occur, forcing untreated sewage to flow back into the environment. This can pose a serious threat to public health and the surrounding environment.
Sewage may drain directly into major watersheds with minimal or no treatment. When untreated, sewage can have serious impacts on the quality of an environment and on the health of people. Pathogens can cause a variety of illnesses. Some chemicals pose risks even at very low concentrations and can remain a threat for long periods of time because of bioaccumulation in animal or human tissue.
There are numerous processes that can be used to clean up wastewaters depending on the type and extent of contamination. There are two basic approaches: to use the waste in the water as a resource (such as constructed wetlands) or strictly as a pollution (such as the majority of today's treatment plants). Most wastewater is treated in industrial-scale energy intensive wastewater treatment plants (WWTPs) which include physical, chemical and biological treatment processes. However, the use of septic tanks and other On-Site Sewage Facilities (OSSF) is widespread in rural areas, serving up to 20 percent of the homes in the U.S.
The most important aerobic treatment system is the activated sludge process, based on the maintenance and recirculation of a complex biomass composed by micro-organisms able to absorb and adsorb the organic matter carried in the wastewater. Anaerobic wastewater treatment processes (UASB, EGSB) are also widely applied in the treatment of industrial wastewaters and biological sludge. Some wastewater may be highly treated and reused as reclaimed water. Increasingly, for most wastewaters ecological approaches using reed bed systems such as constructed wetlands are being used. Tertiary treatment is being increasingly applied and most common technologies are micro filtration or synthetic membranes. After membrane filtration, the treated wastewater is indistinguishable from waters of natural origin of drinking quality (without its minerals). Nitrates can be removed from wastewater by natural processes in wetlands but also via intensive microbial denitrification, for which a small amount of methanol is typically added to provide the bacteria with a source of carbon. Ozone wastewater treatment is also growing in popularity, and requires the use of an ozone generator, which decontaminates the water as ozone bubbles percolate through the tank but is energy intensive.
Disposal of wastewaters from an industrial plant is a difficult and costly problem. Most petroleum refineries, chemical and petrochemical plants have onsite facilities to treat their wastewaters so that the pollutant concentrations in the treated wastewater comply with the local and/or national regulations regarding disposal of wastewaters into community treatment plants or into rivers, lakes or oceans. Constructed wetlands are being used in an increasing number of cases as they provided high quality and productive on-site treatment. Other industrial processes that produce a lot of waste-waters such as paper and pulp production has created environmental concern, leading to development of processes to recycle water use within plants before they have to be cleaned and disposed.
Treated wastewater can be reused as drinking water, in industry (cooling towers), in artificial recharge of aquifers, in agriculture (70 percent of Israel's irrigated agriculture is based on highly purified wastewater) and in the rehabilitation of natural ecosystems (Florida's Everglades).
Around 90% of wastewater produced globally remains untreated, causing widespread water pollution, especially in low-income countries. Increasingly, agriculture is using untreated wastewater for irrigation. Cities provide lucrative markets for fresh produce, so are attractive to farmers. However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users, there is often no alternative for farmers but to use water polluted with urban waste directly to water their crops.
There can be significant health hazards related to using the water in this way. Wastewater from cities can contain a mixture of chemical and biological pollutants. In low-income countries, there are often high levels of pathogens from excreta, while in emerging nations, where industrial development is outpacing environmental regulation, there are increasing risks from inorganic and organic chemicals. The World Health Organization, in collaboration with the Food and Agriculture Organization of the United Nations (FAO) and the United Nations Environmental Program (UNEP), has developed guidelines for safe use of wastewater.
The International Water Management Institute has worked in India, Pakistan, Vietnam, Ghana, Ethiopia, Mexico and other countries on various projects aimed at assessing and reducing risks of wastewater irrigation. They advocate a ‘multiple-barrier’ approach to wastewater use, where farmers are encouraged to adopt various risk-reducing behaviours. These include ceasing irrigation a few days before harvesting to allow pathogens to die off in the sunlight, applying water carefully so it does not contaminate leaves likely to be eaten raw, cleaning vegetables with disinfectant or allowing fecal sludge used in farming to dry before being used as a human manure.
Council Directive 91/271/EEC on Urban Wastewater Treatment was adopted on 21 May 1991, amended by the Commission Directive 98/15/EC. Commission Decision 93/481/EEC defines the information that Member States should provide the Commission on the state of implementation of the Directive.
|Wikimedia Commons has media related to Wastewater.| |
The Coming Of The Prophet
Around the year 570 AD, Muhammad was born into a family of the ruling tribe of Makkah. Makkah, a caravan city in the western region of Arabia, grew around the Ka’abah (the House of God), a shrine of ancient origins built by Abraham and his son Ishmael. Pre-Islamic Arabia was polytheistic and idols used to be housed in and around the Ka’abah. In the 6th century, Makkah was one of Arabia’s thriving commercial centers.
Orphaned as a child, Muhammad spent several years among the Bedouins of the desert, developing a love for the rich Arabic language. As a young man, Muhammad traveled widely with the trade caravans before dedicating his life to Islam.
In 610 God revealed His word to Muhammad through the Angel Gabriel. In this way, Muhammad became the chosen bearer of the divine message and began proclaiming the oneness of God. The name of this new religion, Islam, means “submission to God” The followers of Islam are called Muslims, meaning “those who submit.”
As more revelations enjoined him to proclaim the oneness of God universally, the Prophet Muhammad’s following grew. God’s message as conveyed through Muhammad was not, however, unanimously accepted in Makkah. Pagan worshippers threatened by the new monotheistic religion and merchants anxious to preserve the profitable pilgrimage trade intensified their opposition to the followers of Islam. To foil an assassination plot against him, Muhammad and a small group of his dedicated followers in 622 emigrated to the town of Yathrib, which was later named Madinat Al-Nabi, meaning ‘City of the Prophet’, and now known simply as Madinah. This, the Hijrah or emigration, dates the beginning of the Islamic calendar and the history of the Islamic community. Within the next few years, several battles took place between Muhammad’s followers and the pagans of Makkah. The Prophet Muhammad unified the tribes so successfully that in 628 he and his followers reentered Makkah without bloodshed, destroying the idols in the Ka’abah, and the inhabitants of Makkah embraced Islam.
Less than 100 years from the advent of Islam, the Islamic Empire extended from Spain to areas of India and China. Islam made no distinction based on race, class, or background, and the Muslim world was considered a single worldwide community, the ummah.
Islamic rule thrived well into the 17th century, and while Europe was passing through the Middle Ages, the Islamic civilization made tremendous scientific, medical, literary and artistic advances that have had a lasting impact on the world. |
What you can do
- Track down dragonflies as they emerge and fly before breeding.
- Net specimens to aid identification and appreciation of these incredible creatures.
- Become a “citizen scientist” and submit your records to the British Dragonfly Society’s DragonflyWatch – an easy to access and use recording facility which collects vital information about dragonfly distribution and abundance.
Where to do it
- Bogs, moorland, streams and upland rivers are prime habitat for dragonflies.
- This type of habitat is in abundance nearby the cottage and throughout the Island.
What we provide
- Catching net
- Magnifying glasses and hand held field lens
- ID Guides and books
Advice about the activity
- Dragonflies emerge from water in late spring and early summer with July and August the peak times for flying.
- Flying dragonflies are most easily caught if the net is swung following the dragonfly ie in the direction of flight.
- Perching dragonflies are best captured with an upward swing from behind.
Things to consider
- Observing emergence of dragonflies is an amazing experience although many species do so at night to minimise the risk of predation.
- Never attempt to capture newly emerged specimens as they are too delicate to withstand handling.
- Always return specimens alive where they were captured. |
Submerged Aquatic Vegetation: Where Have All the Grasses Gone?
These small and modest grasses are known as submerged aquatic vegetation or SAV. A habitat in itself, SAV provides functions invaluable to aquatic ecosystems like the Chesapeake Bay. More than a dozen species of SAV are native to the Chesapeake Bay. Salinity, water depth, and bottom sediment are factors which determine where each species can grow. However, the survival of all SAV depends on the amount of sunlight reaching the plants.
These amazing plants provide food and shelter for diverse communities of waterfowl, fish, shellfish, and invertebrates. Like all green plants, SAV produces oxygen, a precious and ever-decreasing commodity in the Chesapeake Bay. SAV filters and traps sediment, which can cloud the water and bury bottom dwelling organisms like oysters. SAV also absorbs nutrients like nitrogen and phosphorus.
Microscopic zooplankton feed on the decaying SAV and, in turn, are food for larger Bay organisms, such as fish and clams. Thus, SAV is a key contributor to the energy cycling in the Bay. SAV is a valuable source of food, especially for waterfowl. In the fall and winter, migrating waterfowl search the sediment for nutritious seeds, roots and tubers. Resident waterfowl may feed on different species of SAV year-round.
Like a forest, field or wetlands a SAV bed serves as habitat for a multitude of aquatic animals. Barnacles and scallop larvae attach to the leaves and stems of eelgrass in the salty waters of the lower Bay. Fish, like bluegill and largemouth bass, live in the freshwater grasses of the upper Bay. Minnows, small anadromous fish, like juvenile striped bass, and blue crabs seek protection as well as food in the SAV beds.
Since the 1960s, well over half of the SAV has disappeared from the Bay waters. Declining water quality, disturbance of SAV beds, and alteration of shallow water habitat all contributed to the decline. The absence of SAV translates into a loss of food and habitat for many Chesapeake Bay species.The initial decline of SAV was most severe in the upper Chesapeake and western shore tributaries. Today, all areas of the Bay has experienced the decline of these important grasses.
The extensive loss of SAV has forced some species of waterfowl to migrate to other wintering areas or to change their feeding habits. Canvasbacks that continue to winter on the Bay now rely mainly on the Baltic clam as a primary food source. Other waterfowl, like redhead ducks, have all but abandoned the Chesapeake. As many as 80,000 redheads once stopped to feed on the Bay grasses. Now, only a few thousand redheads visit the Bay each year. Survival of SAV is affected most by the amount of light that reaches the plants. Reduction of light is the primary cause of the SAV decline. Environmental factors that affect water clarity also affect SAV growth.
Suspended sediment and other solids cloud the water, blocking precious sunlight from the grasses. Excessive amounts of sediment may cover the plants completely. Sources of sediment include runoff from farms, building sites, and highway construction. Shoreline erosion also adds sediment to Bay water. Land development, boat traffic and loss of shoreline vegetation accelerate natural erosion.
Nutrients, although vital to all ecosystems in natural levels, create problems when present in excess amounts. High levels of nutrients stimulate the rapid growth of algae, known as blooms. Algae blooms cloud the water and reduce the amount of sunlight reaching SAV. Certain types of algae grow directly on the plants, further reducing available sunlight.
Nutrients come from three major sources, sewage treatment plants, agricultural fields and fertilized lawns. Every day, more than one billion gallons of treated sewage effluent enters the Bay from treatment plants. This translates into 87 million pounds of nitrogen and 9 million pounds of phosphorus a year! Runoff from farm fields and lawns dumps tons of nutrient-rich fertilizers into the Chesapeake Bay each year. In addition to fertilizers, oils and other pollutants, runoff may also contain herbicides and pesticides that are toxic to aquatic organisms.
Restoring Grasses to the Bay
The U.S. Fish and Wildlife Service and other federal and state agencies, and the Virginia Institute of Marine Science monitor SAV distribution each year. By examining aerial photographs, locations of SAV are mapped for the entire Chesapeake Bay and its tidal tributaries. By monitoring SAV in Chesapeake Bay, biologists can determine which areas need to be protected. By examining historical distribution, areas where SAV once flourished are targeted for restoration.
Citizens also help track the presence of SAV by participating in a volunteer SAV survey. Those with access to shallow water habitats identify SAV beds that may be too small to be seen in the aerial surveys. Frequently, the information provided by volunteers is used by local officials in directing protection and management of waterways and shoreline areas.
Water quality is the key to restoring grasses to the Bay. Scientists have identified the water quality conditions and requirements necessary for the survival of different SAV species. Managers are using these requirements as the basis of recovery plans for various sections of the Bay and its rivers and creeks.
The presence or absence of SAV reflects the general water quality of an area. Like the proverbial canary in a coal mine, SAV can be used as a barometer to gauge the relative health of the Bay or any of its tributaries. Everyone who lives, works and plays in the Chesapeake Bay watershed, directly affects the water quality through everyday activities. The presence of SAV reflects our stewardship for the Chesapeake Bay and the wildlife it supports.
What You Can Do
- Reduce the amount of fertilizers applied to yards.
- Plant vegetation suited to your soil, moisture and climate conditions.
- If you need to fertilize, follow all directions carefully; never apply before storms.
- Prevent shoreline erosion by planting shoreline vegetation.
- If you have access to shallow water areas, volunteer to survey SAV in your area.
- When boating, avoid disturbing SAV beds. Propellers may tear rooted vegetation out of bottom sediments.
- Waterfront property owners should avoid using herbicides that may harm delicate SAV plants. |
Kangaroo Island Shows Burn Scars On One Third of the Land Mass
NASA’s Terra satellite provided before and after imagery that showed the extent of the fires that have been ravaging Australia’s Kangaroo Island. Kangaroo Island lies off the mainland of South Australia, southwest of Adelaide. About a third of the island is made up of protected nature reserves which are home to native wildlife which includes sea lions, koalas and diverse and endangered bird species, including glossy black-cockatoos which have been brought back from the brink of extinction over the last two decades.
In the western part of Kangaroo Island, specifically in Flinders Chase National Park, penguin colonies and famous coastal rock formations are found. Kangaroo Island is Australia’s third largest island after Tasmania and Melville Island. In addition to it being a very popular tourist destination for both Australians and nature lovers, the island even boasts a colony of Ligurian honey bees which are the world’s only pure-bred and disease-free population of this type of bee.
Which makes the devastating bushfires that have laid waste to almost one-third of the island not only just a major tragedy for the island but an ecological tragedy as well. The bushfires began as lightning strikes within Flinders Chase National Park. Ecologists within the park put estimates of the number of koalas that have perished in the fire at 25,000 which is half the island’s population of the popular animals. NASA’s fleet of satellites are able to monitor from their various satellites the extent of the damage and the areas continuing to burn which assist firefighters in fighting these major disasters.
The two images on this page show Kangaroo Island both before and after the bushfires. (The second image is from December 16, 2019 and the top image was taken on January 7, 2020.) The devastation can clearly be seen as one-third of the island (155,000 hectares/383,013 acres) shows burn scars as well as areas that are still on fire. These images were captured by NASA’s Terra satellite using its MODIS instrument. The MODIS (Moderate Resolution Imaging Spectroradiometer) instrument is able to overlay reflective bands of color to highlight areas burned and distinguish them from areas of regular vegetation.
Burned areas or fire-affected areas are characterized by deposits of charcoal and ash, removal of vegetation and/or the alteration of vegetation structure. When bare soil becomes exposed, the brightness in Band 1 may increase, but that may be offset by the presence of black carbon residue; the near infrared (Band 2) will become darker, and Band 7 becomes more reflective. When assigned to red in the image, Band 7 will show burn scars as deep or bright red, depending on the type of vegetation burned, the amount of residue, or the completeness of the burn. Vegetation is very reflective in the near infrared (Band 2), and absorbent in Band 1 and Band 7. Assigning that band to green means even the smallest hint of vegetation will appear bright green in the image.
NASA’s satellite instruments are often the first to detect wildfires burning in remote regions, and the locations of new fires are sent directly to land managers worldwide within hours of the satellite overpass. Together, NASA instruments detect actively burning fires, track the transport of smoke from fires, provide information for fire management, and map the extent of changes to ecosystems, based on the extent and severity of burn scars. NASA has a fleet of Earth-observing instruments, many of which contribute to our understanding of fire in the Earth system. Satellites in orbit around the poles provide observations of the entire planet several times per day, whereas satellites in a geostationary orbit provide coarse-resolution imagery of fires, smoke and clouds every five to 15 minutes.
NASA’s Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks “right now.” Actively burning fires, detected by thermal bands, are shown as red points. |
Explosives are often played with as though they were toys. The persons playing with explosives are often too young to have accumulated sufficient formal education in chemistry and physics to understand the hazards involved. One intent here is to supply sufficient information to allow intelligent choices to be made in the handling and use of explosives.
The misuse of explosives causes a knee-jerk reaction against any scientific discussion of the materials. This is unfortunate. They have unique properties that can help us understand materials in general: they "talk to us" with energy. You can build defects into crystals and watch the effects through changes in the explosives' thermal properties and sensitivity. You can easily follow absolute-rate processes. True scientific applications of explosives can be fascinating and rewarding. We hope that the information presented here will suggest methods for using explosives in research.
Three broad categories of hazards can be observed in the use of explosives: sensitivity, stability, and toxicity. Each type of hazard must be considered before explosives are handled.
Safety tests for impact, friction, shock, and sparks generate relative scales for evaluating hazards. Different explosives are compared with one another. It can be stated that TNT is less sensitive than PETN; however, a quantitative statement can not be made about exactly how hard either must be hit to cause initiation under all conditions. Relative scales lack credibility: some small change in experimental conditions can cause errors in hazards interpretations. Many different relative tests must be run to improve the probability that all hazards have been identified.
Safety is estimated from experience with the materials. The experience usually involves an accident and the subsequent accident investigation. If one explosive rarely causes accidents and another is found to be less sensitive to impact, you might jump to the assumption that it will be less hazardous. That is a very dangerous assumption. Each explosive, formulation, and application must be investigated by many different safety tests.
All initiations are thermal in nature. Detonations are characterized by a constant-velocity shock wave; however; the heat generated by chemical reactions supports the shock wave. An understanding of explosives requires an understanding of their thermochemical properties.
Thermochemistry of explosives:
Self-heating accidents have often occurred when small-scale procedures have been scaled up without considering the effects of size. Safe amounts can be estimated in very straightforward ways. Other accidents have occurred when additional materials were added to previously safe operations. Such "compatibility" problems can be observed before they become a hazard.
A large number of tests has been used to observe relative thermal stabilities. In addition, some more recent quantitative methods can be applied to predicting safe temperature ranges for many important explosives. Each approach will be discussed; however, no attempt is being made to make a comprehensive review. All comments and perspectives are based on our experience alone.
Relative Tests for Thermal Stability and Compatibility:
Tests Involving Chemical Product Detection or Analysis:
All of the earliest tests are in this class, and many of the tests are still in use in different parts of the world. Erroneous conclusions will always be drawn from these tests when results are used to compare stabilities of materials that decompose to produce different products.
Abel Test: One of the earliest tests is the Abel Test (1875). It observes the time required to change the color of starch/iodide paper when 1-gram samples are heated to 180 F. It is still used in the quality control of commercial cellulose nitrate (NC), nitroglycerin (NG), and nitroglycol. It can not be used to compare different types of explosives.
Vieille Test: The sample is heated at 110 C with a strip of litmus paper (1896). The sample is opened to the air overnight at room temperature, and the procedure is repeated until the paper turns red within one hour. The overall heating time is the quantity measured. A propellant powder passed by this test self heated to explosion in 1911, and two ships were sunk.
Bergmann-Junk Test: The test involves heating the sample to 132 C and determining extracted nitrites (1904). The test was much modified by Siebert in 1942, who used H2O2 as the trapping liquid, added a better apparatus for trapping the NO, and titrated total acidity. The test works well for quality control of a single explosive, but it can not be used to compare dissimilar materials.
Leclercq's Test: This test (1950) involves the determination of the amount of NO and NO2 liberated at 90 C as a function of time.
Changes in product composition will confuse all of these tests. For example, nitroguanidine decomposes to produce some ammonia. Ammonia changes total acidity and can react with oxides of nitrogen. None of the chemical tests observe the product of decomposition that causes self-heating accidents: heat.
Differential Thermal Analysis (DTA):
When self-heating is the problem, it seems only logical to make heat the quantity measured. DTA observes the production or absorption of heat by a sample. |
When a toddler learns to get dressed, they’re learning a sequence of instructions. They know that they need to put on both their pants and trousers. If they get the order right, they’ll look nice and smart. If they get the order wrong they’ll look like a superhero.
Getting the order wrong with instructions in your code doesn’t always lead to such a fun result, so planning out the sequence of instructions clearly in your head (or on paper) can save a lot of time and frustration.
There are some hints to help you with the sequence of instructions in code:
- Set before you get
If you’re trying to get the data stored in a variable, your code should have already set something to be stored in that variable.
It’s a good idea to set your variables to sensible initial values early on in your code.
- Split your sequences into sections
Some people like to show off by writing long complicated lines of code that do all sorts of clever things all in one go. There’s nothing wrong with that if it works but your code will be much easier to read and you’ll be much less likely to make mistakes if you keep things as simple as possible.
It helps to split complex calculations into a sequence of smaller, easier to understand calculations over several lines of code.
Adding empty lines between sections of code that do different tasks and commenting each ‘paragraph’ of code lets you describe each sequence so you’re less likely to make mistakes.
- Talk before you type
If you’ve got a complex problem to solve and you’re not sure where to start, start by explaining what you need your program to do. Even if you end up talking to yourself (some people use plastic rubber ducks!): the process of talking through (or scribbling down) the problem can help you see the sequence which, in turn, shows you where to start.
Generally speaking, python will start at the top of a file and run each line in turn, unless it jumps to call procedures or functions that you’ve defined elsewhere in your code.
On the next page you’ll get some code examples that you can try out for yourself. |
Creating a table is the very basic operation in the database. Table is created using a CREATE TABLE statement. The create table command requires the following:
- Table name
- Column names
- Column data types
- Column default values (Optional)
- Indexes (if any)
- Characterset, collation and Engine (Optional).
Basic table structure:
Example of a create table command:
create table table_1( id INT NOT NULL AUTO_INCREMENT, name VARCHAR(100) NOT NULL, class VARCHAR(40) NOT NULL, DOB DATE, PRIMARY KEY ( id ) ) engine='innodb';
Fig 7.1 Example of table creation.
Now here is the little description of above example:
Here four columns are used named id, name, class, DOB with data types INT, VARCHAR, CLASS and date in creating the table table_1. Here NOT NULL is used to indicate that none of the columns allow NULL except DOB. There a PRIMARY key is used on id column which means this is unique key index and can be used for reference to other tables. Here the id is AUTO INCREMENT also which means this id is generated aiutomatically on insertion of a new row and is incremented by one by default.And at last the table engine which is INNODB here.
You can check and validate the table creation by the command show tables:
This command lists all the tables present in the current database. Here the table table_1 exists which is created via above example.
NOTE: Before creating the table you must be in some database means you must have to enter in a database by the command “use database database_name” or “\u database_name”.
If you want to check the details of the table you can use desc command means description of the table followed by table name. Here is the Example :
Command: DESC TABLE_NAME ;
If you want the output in a query format as you create it then use the command show create table as :
Command: SHOW CREATE TABLE TABLE_NAME :
Create table has an another form in which you can create a new table from the old table by using the command CREATE TABLE LIKE command:
Command: CREATE TABLE TABLE_NEW LIKE TABLE_OLD ;
Every table creation in the MySQL makes physical files in the data directory of mysql server under the directory named same as of database name. Although the physical files depend upon the engine of the table. For example as we read in previous chapter of storage Engine MyISAM creates the three files .frm, .myi and .myd wheras the Innodb creates the frm file only and data exists in the main ibdata file. |
Interested in discussing these findings with other teachers? Follow the Edmodo Topic for this series!
In this series, we’re studying student responses to questions from the American Mathematics Competition (AMC) attempted by hundreds of thousands of students on Edmodo. We saw in the first article that a large data sample like this provides unique opportunities to gain insights into how students think. In the second article, we delved deeper into questions on ratios and proportions and saw how students often use the wrong logic because it worked for them in some other similar-looking question. Being aware of these pitfalls allows teachers to alert students to them and gradually help them overcome them.
This time, we’ll look at a few questions related to area and perimeter and how students answer them.
In our experience, student misconceptions arise when there is an underlying concept that leads to common use of procedures or formulas, but the curriculum emphasizes the formulas more than the concept. Secondly, the concepts rarely have real-world applications to the students themselves..
A fantastic example of these misconceptions is when students study area and perimeter. These concepts are fundamental ideas related to space and measurement, but it appears that most curriculum’s emphasis is more on the formula to calculate them than the idea itself. Students learn formulas for the areas of triangles, various types of quadrilaterals, other polygons, circles, semi-circles and so on. They then move on to surface area and volume — more formulas! Is it surprising that when asked ‘What is area?’ more children answer ‘length times width’ than ‘the space covered by a closed flat shape?’ Is it surprising that many students say that irregular shapes (like a leaf, for example) do not have an area?
The Grade 8 AMC test had this question:
Karl’s rectangular vegetable garden is 20 feet by 45 feet, and Makenna’s is 25 feet by 40 feet. Whose garden is larger in area?
A. Karl’s garden is larger by 100 square feet. (14%)
B. Karl’s garden is larger by 25 square feet. (19%)
C. The gardens are the same size. (25%)
D. Makenna’s garden is larger by 25 square feet. (20%)
E. Makenna’s garden is larger by 100 square feet. (22%)
Attempted: 48046 | Skipped: 16
22% of the students got this question correct. But one of the wrong answers, that the gardens are of equal area ©, is chosen by even more students! This is extremely unusual. The most commonly selected answer is usually the correct one, and when it isn’t, it justifies going deeper into the question and responses.
When we look at the graph which shows how students have performed at different levels of total score in the paper, it appears confused. There is no strongly increasing selection of the correct answer among the better performing students like the data from previous articles. In fact, at no score level (except the perfect score) do more than 60% of the students select the correct answer!
Option vs. Average Score in full ‘paper’
And yet, we see that those who chose option E have performed significantly better than all the others. Overall this suggests that the question has challenged and stumped many students, but the best ones have answered it correctly.
Where are the children going wrong? Some students may be applying the perimeter formula instead of calculating the area. The perimeter of both Karl and Makenna’s fields would indeed be the same, but not the area.
Still, it is surprising that so many students would get this question wrong — is it possible that students simply guessed or did not answer the question seriously? We’ll have more on that later.
Let us look at one more question related to areas of overlapping shapes. We saw similar patterns in other questions on this topic too.
The shaded region formed by the two intersecting perpendicular rectangles, in square units, is
A. 23 (8%)
B. 38 (41%)
C. 44 (36%)
D. 46 (15%)
Attempted: 2418 | Skipped: 0
While 41% of students have gotten this question from the grade 8 AMC test correct, we can see that a substantial percentage of students have answered C. 44. How do these students get that answer? They have calculated the area of each rectangle (20 sq. units and 24 sq. units) and added them. They have not subtracted the overlap area which is double-counted in that addition.
Is that a careless mistake? If yes, we could hypothesize that if this (or a similar) question were given to the students again, many who made the careless mistake wouldn’t. Experience suggests that careless mistakes occur at a much lower frequency — less than 5% usually. An answer given by more than a third of a student more likely represents an important misconception. This means that if the question is given again, most of these students would give that same answer. Unlike a careless mistake, a misconception needs to be addressed and remediated.
The students are actually associating the area of a rectangle with the formula length into width, and applying it inappropriately. They are not thinking about the physical meaning of area, hence the overlap does not occur to them.
It is also possible that students simply perform some operations using the numbers given in the question, in this case (8 x 3) + (2 x 10). You may be aware of the research around the question “A captain owns 26 sheep and 10 goats. How old is the captain?” (If not, you can look it up on Wikipedia.)
Do you remember the question from the last article? When asked the ratio of the number of girls to boys in a classroom of 28 students, more than a quarter selected 7:4. Since 7 x 4 = 28, sometimes these numbers pop up and take the unsure student towards the wrong answer. Since the number of such students is substantial, it is important for us to understand and try and address this issue.
What are some of the takeaways from today’s examples and discussion?
But when we look at large scale data and analyze them, what if students are just guessing? Or not answering questions with seriousness? What if the engagement is missing — possibly due to frustration, boredom or something else? Do share your thoughts and comments on these points. We shall examine these factors in the next article and how we can eliminate some of them from contaminating our results. We will also look at common mistakes students are making while solving word problems with a number of examples from the Edmodo — AMC dataset!
Edmodo acknowledges the inputs of Educational Initiatives, Inc. which provided the question performance analysis used in the article. |
A primary source is the raw evidence or original document that is analyzed as part of the research process. What is considered a primary source varies somewhat by discipline, but examples include scientific study results, data, legal documents, interviews, historical artifacts, etc. Primary sources are created by witnesses or recorders who experienced the events or circumstances, providing firsthand testimony or direct evidence. Typically primary sources are created contemporaneously with the event or circumstances, but primary sources can also include reflections recorded later, such as autobiographies, memoirs, and oral histories.
Secondary sources interpret or analyze primary sources. Examples of secondary sources include scholarly articles, scholarly books, magazine articles, etc. Tertiary sources are a step further removed in the research process, typically compiling the findings of secondary sources. Examples of tertiary sources are reference books and textbooks.
Examples of Primary Sources |
All acids and bases do not ionize or dissociate to the very same level. This leads to the statement that acids and also bases are not every one of equal strength in developing H+ and OH- ions in solution. The terms "strong" and also "weak" give an indication of the toughness of an acid or base. The terms strong and weak explain the capacity of acid and base options to conduct electricity. If the acid or base conducts electricity strongly, it is a solid acid or base. If the acid or base conducts electrical power weakly, it is a weak acid or base.
You are watching: What determines the strength of an acid or a base
Demonstration of Acid and also Base Conductivity
The instructor will test the conductivity of assorted services via a light bulb apparatus. The light bulb circuit is infinish. If the circuit is completed by a solution containing a huge variety of ions, the light bulb will certainly glow brightly indicating a strong capacity to conduct electrical power as displayed for HCl. If the circuit is completed by a solution containing huge numbers of molecules and either no ions or few ions, the solution does not conduct or conducts very weakly as shown for acetic acid.
where HA is the concentration of the acid at equilibrium, and also A- is the concentration of its conjugate base at equilibrium and also for bases the expression will be
where B is the concentration of the base at equilibrium and also HB+ is the concentration of its conjugate acid at equilibrium
The stronger an acid is, the reduced the pH it will certainly produce in solution. pH is calculated by taking the negative logarithm of the concentration of hydronium ions. For strong acids, you can calculate the pH by simply taking the negative logarithm of its molarity as it entirely dissociates right into its conjugate base and also hydronium. The exact same goes for strong bases, other than the negative logarithm gives you the pOH as opposed to the pH. For weak acids and bases, the greater the Ka or Kb, the even more acidic or standard the solution. To uncover the pH for a weak acid or base, you have to use the K equation and also a RICE table to recognize the pH.
See more: Why Does Kodi Take So Long To Exit Ing Kodi, Kodi Often Hangs On Exit
All acids have a conjugate base that creates when they react through water, and also similarly, all bases have a conjugate acid that reacts as soon as they form with water.1 You can judge the family member stamina of a conjugate by the (K_a) or (K_b) value of the substance because (K_a imesK_b) is equal to the ionization consistent of water, Kw which is equal to (1 imes 10^-14) at room temperature. The better the Ka, the more powerful the acid is, and also the weaker its conjugate base is. Similarly, the greater the Kb, the more powerful the substance is as a base, and also the more weakly acidic its conjugate acid is.1
Calculation of Ka
For an acid that reacts via water in the reaction
where each bracketed term represents the concentration of that substance in solution.
Relation of Kw, Kb, Ka
Partial List of Strong Acids: Hydrochlroic acid (HCl), Nitric Acid (HNO3), Perchloric Acid (HClO4), Sulfuric Acid (H2SO4)
Partial List of Strong Bases: Sodium Hydroxide (NaOH), Barium Hydroxide (Ba(OH)2), Calcium Hydroxide (Ca(OH)2), Lithium Hydroxide (LiOH) (Hydroxides of Group I and also II aspects are mostly strong bases)
Partial List of Weak Acids: Acetic Acid (CH3COOH), Carbonic Acid (H2CO3), Phosphoric Acid (H3PO4)
Partial List of Weak Bases: Ammonia (NH3), Calcium Carbonate (CaCO3), Sodium Acetate (NaCH3COO) |
Heat Transfer Worksheet Middle School Heat Worksheet
Posted in Worksheet, by Kimberly R. Foreman
Heat Transfer Worksheet Middle School Heat Worksheet.
Heat up your lesson with a useful resource. an informative video describes the three main types of heat transfer conduction, radiation, and convection. it explains how these methods of heat transfer should be taken in consideration when. Methods of heat transfer worksheet please note you may complete this assignment as many times as you like, but only the first attempts will be graded.
the scores will be averaged together. A page worksheet that covers heat transfer by conduction, convection, and radiation through a page reading and review questions. pages features a reading exercise on temperature, thermal energy, and the three main methods of heat transfer, including the following what, make copies of the heat transfer worksheet.
Methods heat transfer worksheet answers heat transfer. Methods heat transfer worksheet energy worksheet 2. Conduction convection radiation worksheet images. Thermodynamics worksheet answer key heat. Current events answers key methods heat transfer. Heat transfer science teaching resources heat. Images conduction convection current events. |
How much do you know about dog ticks?
Ticks are arachnids, typically 3 to 5 mm long, part of the order Parasitiformes. Along with mites, they constitute the subclass Acari. Ticks are ectoparasites (external parasites), living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians.
Almost all ticks belong to one of two major families, the Ixodidae or hard ticks, and the Argasidae or soft ticks. Adults have ovoid or pear-shaped bodies, which become engorged with blood when they feed, and eight legs. In addition to having a hard shield on their dorsal surfaces, hard ticks have a beak-like structure at the front containing the mouthparts, whereas soft ticks have their mouthparts on the underside of the body. Both families locate a potential host by odor or from changes in the environment.
Ticks have four stages to their lifecycle, namely egg, larva, nymph, and adult. Ixodid ticks have three hosts, taking at least a year to complete their lifecycle. Argasid ticks have up to seven nymphal stages (instars), each one requiring a blood meal. Because of their habit of ingesting blood, ticks are vectors of diseases that affect humans and animals.
On the infographic below, you can read some basic info about the most common dog ticks.
Tick species and the diseases they can cause
- Ixodes scapularis (Deer tick)
– It takes 2 years to complete their life cycle and is found predominately in deciduous forest. Their distribution relies greatly on the distribution of its reproductive host, white-tailed deer. Both nymph and adult stages transmit diseases such as Lyme disease, Babesiosis, and Anaplasmosis.
Dermacentor variabilis (American Dog Tick)
– Found in grassy fields. They feed on a variety of hosts, ranging in size from mice to deer, and nymphs and adults can transmit diseases such as Rocky Mountain Spotted Fever and Tularemia. American dog ticks can survive for up to 2 years at any given stage if no host is found.
Rhipicephalus sanguineus (Brown Dog Tick)
– All life stages of this tick can transmit Rocky Mountain Spotted Fever rickettsia (Rickettsia rickettsia) to dogs, and rarely to humans. Both nymphal and adult stages can transmit the agents of canine ehrlichiosis (Ehrlichia canis) and canine babesiosis (Babesia canis vogeliand Babesia gibsoni-like) to dogs.
- Dermacentor andersoni
– All life stages of this tick can transmit Colorado tick fever virus (CTFV) to humans, and Rocky Mountain spotted fever (RMSF) rickettsia (Rickettsia rickettsii) to humans, cats, and dogs. Rocky Mountain wood tick saliva contains a neurotoxin that can occasionally cause tick paralysis in humans and pets
- Amblyomma americanum
– The larvae do not carry disease, but the nymphal and adult stages can transmit the pathogens causing Monocytic Ehrlichiosis, Rocky Mountain Spotted Fever and ‘Stari’ borreliosis.
Special thanks to Tick Encounter Research Center for the tick images and info.
If you would like to read more about external parasites, read “Most common external parasites in dogs and cats” on our blog.
Project dedicated to support and help to improve Veterinary Medicine. Sharing information and raising discussions in the veterinary community. |
Dolphins, seals and other sea mammals have a monochromatic view, only a green photoreceptor.
Most mammals have bichromatic B.G vision:
The evolution of trichromatic color vision in primates occurred as the ancestors of modern monkeys, apes, and humans switched to diurnal (daytime) activity and began consuming fruits and leaves from flowering plants.
Wiki evolution of color vision (see top ref to main article)
Humans see R.G.B. and bats see G.B.UV.
Some birds, shrews, tenrecs and rats can use simpler echolocation. (wiki)
Birds R.G.B.UV have five types of cones including four single cones, which support tetrachromatic color vision and a double cone, which is thought to mediate achromatic motion perception.
Rats Grey-UV (Rattus norvegicus) have two classes of cone, one containing an ultraviolet (UV)-sensitive photopigment and the other housing a pigment maximally sensitive in the middle (M) wavelengths of the visible spectrum.
Reindeer can see UV.
UV vision isn't possible with big eyes:
...the eyes of smaller birds were more UV transparent than the eyes of larger birds. This means that small birds, such as songbirds, can take full advantage of ambient UV light, while larger birds, such as swifts and raptors, block a lot of the UV light from reaching the retina.
"If you want to be highly UV sensitive — be a UV specialist — you have to be small," Lind said. "For me, that is quite thrilling because it means that your perception of the world is dependent on your physical size." |
Guided Reading Pack
This Guided Reading Pack is linked to Health and Fitness and is an information text about exercise.
National Curriculum Objectives
Reading: English Y1: Becoming very familiar with key stories, fairy stories and traditional tales, retelling them and considering their particular characteristics
SPAG: English Y1: Joining words and joining clauses using and
Level of this Pack:
Old National Curriculum (England): 1a
New National Curriculum (England): Year 1 Secure/Year 2 Emerging
Book Band: Turquoise
PM Benchmark Level: 17 & 18
Reading Recovery Level: 17 & 18
Reading Age: 7 - 7 1/2
The pack includes:
Oral teacher questions with answers for guided reading sessions. Each question is linked to the New National Curriculum (England).
Follow-up work with answers.
Spelling, punctuation and grammar work related to the text with answers.
Vocabulary work related to words in the story.
This resource is available to download with a Premium subscription. |
It is Halloween once again, and if there’s a perfect tree for the Halloween season it is the American sycamore. In October, when the trees in the James River watershed begin to change color and shed their leaves, the ghostly trunk of the American sycamore (Platanus occidentalis) stands out among the sea of orange and red. Sycamores are also called buttonwood or buttonball trees because of the 1-inch balls that hang from the tree through the winter months and fall each spring.
While many trees shed their bark by crumbling bit-by-bit, the American sycamore is among a grouping of Exfoliating Bark Trees. You can recognize a sycamore by its exfoliating bark that looks almost white amid the darker tree trunks. Think of it as a mummy losing its wrappings or a zombie tree and you’ll get the picture. This peeling bark is the result of the tree’s growth process. Unlike most other trees that have bark that stretches or infills as the trunk grows, the sycamore’s rigid bark lacks elasticity and flakes off to accommodate the growth of new wood. Arborists believe that trees that shed their bark have environmental advantages and are better able to get rid of pests, fungus and bacteria.
Found throughout the eastern US, the sycamore is one of the largest trees in the eastern forest. They can reach a height of 70 to 100 feet with a canopy spread of 60 to 80 feet. While surveying for the Kanawha Canal, George Washington recorded a sycamore tree with a trunk that measured 45 feet in circumference. Also monstrous in size are its leaves, the largest of any North American tree, which often measure up to 8 inches across.
Keeping with the Halloween tree theme, the sycamore is susceptible to anthracnose fungus which can affect stem growth and form “witches’ brooms” or leafless clusters of sprouts that form on limbs. For this reason, anthracnose resistant hybrids of the sycamore, like the London planetree, are better suited to an urban environment as a shade tree.
This large tree is most often found in a riparian setting, so the next time you’re near the James River, look for a ghostly pale tree trunk. You might by surprised by how many American sycamore trees you see. |
Magnetoreception – a Quantum Sixth Sense
Imagine you are dropped off hundreds of miles away from your home, deep in some unknown forest. Would you be able to find your way home using only your five basic senses – sight, smell, sound, taste, and touch? If you’re anything like me, you may struggle to navigate around your own city without help from a GPS. However, some animals are actually able to accomplish this impressive navigational feat, and scientists believe they may be using a special sixth sense called magnetoreception. This is the ability to sense magnetic fields, usually that of the Earth, in order to orient and navigate.
Most of the evidence we have for magnetoreception in animals comes from studies of migratory birds, such as homing pigeons, which are able to find their way home after being taken hundreds of miles away from their nests. However, lots of other animals have this magnetic compass as well. For instance, sea turtles, which migrate extensively throughout their lives, use a combination of wave direction and the Earth’s magnetic field to make their way across oceans as they travel between feeding and nesting sites . There is also evidence that Pacific salmon, which spend years out in the ocean before finding their way back to their home river to lay eggs, use a magnetic sense to orient themselves in the waters . Magnetoreception doesn’t only exist in migratory animals, however. There are also observations that suggest magnetoreception exists in mammals, and that in addition to helping with navigation, this sense may help animals carry out daily spatial orientation tasks. For example, cows grazing in pastures tend to orient themselves to be aligned with the magnetic north-south poles, even after ruling out other explanations such as shielding from the wind or basking in the sun . Off-leash dogs tend to align themselves with the magnetic poles when defecating or urinating , and a recent study suggests that dogs also use magnetoreception while scouting . Red foxes, who jump high into the air and then nosedive into the snow to catch prey (a technique adorably called “mousing”), are thought to use magnetic alignment to help them determine the precise distance and direction of attack . How exactly any of these animals are able to detect magnetic fields has long been a mystery. Recently, thanks to researchers studying magnetoreception, we are beginning to fill in the picture.
There are currently two leading hypotheses about how animals are able to detect magnetic fields: one is a chemical reaction that involves a type of protein called a cryptochrome, and the other is a mechanical reaction that involves a form of iron called magnetite.
The basis for the cryptochrome hypothesis for magnetoreception stems from the discovery that the magnetic compass of some animals depends on light (meaning the magnetic sense only works at certain wavelengths or intensities of light), suggesting some kind of light-dependent chemical reaction must be taking place. In 1978, Klaus Schulten, a German-American biophysicist studying the impact of magnetic fields on biochemical reactions, proposed such a mechanism – a radical pair reaction . Radicals are molecules with unpaired electrons (negatively charged subatomic particles that exist in all atoms), and they are produced when light excitation causes one molecule to release one of its electrons and give it to another molecule, creating a pair of radicals (the radical pair). These unpaired electrons are affected by magnetic fields in a manner that depends on the precise orientation of these fields. In this way, the reaction could serve as an internal magnetic compass. Interestingly, there is only one known type of protein in vertebrates that is capable of forming these light-induced radical pairs – cryptochrome. Even more interestingly, scientists have found high levels of cryptochromes in the retinas of migratory birds, suggesting that these animals may be able to see magnetic fields!
Two research groups published articles in 2018 giving evidence that a specific cryptochrome in the bird eye’s retina, Cry4, may play a role in magnetoreception. In one study, scientists measured the gene expression of three different types of cryptochrome proteins, Cry1, Cry2 and Cry4, in the eyes of zebra finches throughout the day . They were looking to see whether the expression levels of these proteins changed throughout the day, as cryptochromes are also known to be involved in the day-night biological clock (the circadian rhythm). They hypothesized that if any of these cryptochromes were involved in magnetoreception, which is used not only for migration but also for spatial orientation tasks required throughout the day, the expression levels should be relatively constant. On the other hand, if the expression levels of these cryptochromes fluctuated or showed any circadian rhythmicity, that would be evidence that they are primarily involved in the night-day cycle rather than magnetoreception. They found that Cry1 and Cry2 varied throughout the day as expected for circadian clock genes, while Cry4 was expressed at constant levels over time.
Around the same time, the other research group measured cryptochrome expression levels in birds during migratory and non-migratory seasons . They found that Cry4 was expressed at much higher levels during migratory seasons compared to non-migratory seasons, while Cry1 and Cry2 levels were relatively unchanged. Together, these studies provide evidence that the Cry4 cryptochrome is a prime candidate magnetoreceptor, at least in migratory birds. However, this leaves the question of how birds use magnetic fields to migrate at night, when there is no light to trigger the radical-pair reaction.
The other leading hypothesis for a magnetoreception mechanism involves crystals of a form of iron called magnetite, which is the most strongly magnetic naturally occurring mineral. Magnetite crystals are widely found in organisms, from magnetotactic bacteria to various animals. The basic idea here is that external magnetic fields exert a force on the crystals (just like two magnets attracting each other) and cause them to rotate, and this movement could be detected by nearby cells designed to notice such movement, potentially serving as a magnetic sensor.
As mentioned before, much of our scientific research on magnetoreception has been done in birds. Clusters of magnetite have been found in the upper beak of migratory birds, including homing pigeons , which is innervated by the trigeminal nerve (an important nerve for sensations in the face). Further, scientists demonstrated that changing magnetic fields lead to high neuronal activation in and near the brain areas receiving input from this nerve . This is solid evidence that birds use at least two different strategies to detect magnetic fields – both cryptochromes and magnetite – which may be particularly helpful since the cryptochrome mechanism requires daylight, and birds do not migrate strictly during the day.
While the magnetite hypothesis seems to make sense in light of the evidence we have from birds, scientists are hesitant to assume a similar mechanism is occurring in some other animals in which we have found magnetite. Iron is required for proper biological functioning in most organisms, so the presence of magnetic iron molecules does not necessarily imply a meaningful interaction with magnetic fields, unless it can be shown to occur at specific and consistent locations in the body and is linked to the nervous system (such as the magnetite in the bird beak linked to the facial nerve) . Because so many animals have naturally occurring magnetite in their bodies, researchers are still studying whether and how it may contribute to magnetoreception.
Do humans have a magnetic sense?
As magnetoreception is a fascinating topic, it may come as no surprise that scientists have been trying to determine whether humans have this sense in any capacity. Cryptochromes, which are not unique to birds and often function as circadian proteins in animals, also exist in the human eye. In 2011, researchers performed a study with fruit flies, which can naturally detect magnetic fields with their cryptochromes. They showed that removing the flies’ Cry genes abolished their ability to respond to magnetic fields, and that inserting the human Cry2 gene into the flies not only recovered this ability, but did so in a light-dependent manner . This suggests that the human Cry2 protein can perform a similar magnetoreceptive role as the cryptochromes in the bird eye. However, the authors concede that this is not evidence that this gene carries out the same function in humans – indeed, we have no evidence to believe humans can see magnetic fields. Additionally, magnetite crystals have been found in the human brain , but there has been no evidence that they allow us to detect magnetic fields… until recently.
In 2019, a research team led by Dr. Connie Wang at California Institute of Technology measured electrical activity on the human scalp with electroencephalography (EEG) while varying the external magnetic field to mimic what a person might experience while moving around in the world . They found that varying the field consistently led to a drop in amplitude of alpha waves, which are typically associated with a brain at rest (and a reduction of alpha wave amplitude is associated with sensory stimulation like vision or cognitive processing – basically anything other than rest). Further, this consistent drop in alpha amplitude only occurred when the magnetic field was rotated horizontally and the vertical field held static and directed downwards, which mimics the rotation of the Earth in the Northern Hemisphere. Fascinatingly, they were able to rule out any free-radical/cryptochrome based mechanism (while the explanation is beyond this article, briefly: the neural response was sensitive to the polarity of the magnetic field, which cryptochromes are not). Therefore, while this is not direct evidence per se for the magnetite hypothesis, such a process remains the only plausible mechanism we currently know of to explain the results.
Nonetheless, at the end of the day these findings are still not proof that humans can actually detect magnetic fields, consciously or subconsciously. Indeed, because magnetite is distributed widely throughout our brain tissue and is not (as far as we know) connected to our nervous system, it is unlikely that we can use its interaction with external magnetic fields in any meaningful way. But the fact that we can detect neural responses to changes in magnetic fields is still fascinating, as is the fact that many animals today still actively sense and respond to magnetic fields.
Goff, M., Salmon, M., & Lohmann, K. J. (1998). Hatchling sea turtles use surface waves to establish a magnetic compass direction. Animal behaviour, 55(1), 69–77. https://doi.org/10.1006/anbe.1997.0577
Naisbett-Jones, L. C., Putman, N. F., Scanlan, M. M., Noakes, D., & Lohmann, K. J. (2020). Magnetoreception in fishes: the effect of magnetic pulses on orientation of juvenile Pacific salmon. The Journal of experimental biology, 223(Pt 10), jeb222091. https://doi.org/10.1242/jeb.222091
Begall, S., Cerveny, J., Neef, J., Vojtech, O., & Burda, H. (2008). Magnetic alignment in grazing and resting cattle and deer. Proceedings of the National Academy of Sciences of the United States of America, 105(36), 13451–13455. https://doi.org/10.1073/pnas.0803650105
Hart, V., Nováková, P., Malkemper, E. P., Begall, S., Hanzal, V., Ježek, M., Kušta, T., Němcová, V., Adámková, J., Benediktová, K., Červený, J., & Burda, H. (2013). Dogs are sensitive to small variations of the Earth’s magnetic field. Frontiers in zoology, 10(1), 80. https://doi.org/10.1186/1742-9994-10-80
Benediktová, K., Adámková, J., Svoboda, J., Painter, M. S., Bartoš, L., Nováková, P., Vynikalová, L., Hart, V., Phillips, J., & Burda, H. (2020). Magnetic alignment enhances homing efficiency of hunting dogs. eLife, 9, e55080. https://doi.org/10.7554/eLife.55080
Červený, J., Begall, S., Koubek, P., Nováková, P., & Burda, H. (2011). Directional preference may enhance hunting accuracy in foraging foxes. Biology letters, 7(3), 355–357. https://doi.org/10.1098/rsbl.2010.1145
Schulten, K., Swenberg, C., & Weller, A. (1978). A Biomagnetic Sensory Mechanism Based on Magnetic Field Modulated Coherent Electron Spin Motion. Zeitschrift für Physikalische Chemie, 111, 1 – 5.
Pinzon-Rodriguez Atticus, Bensch Staffan and Muheim Rachel (2018). Expression patterns of cryptochrome genes in avian retina suggest involvement of Cry4 in light-dependent magnetoreceptionJ. R. Soc. Interface.152018005820180058
Günther A, Einwich A, Sjulstok E, et al. Double-Cone Localization and Seasonal Expression Pattern Suggest a Role in Magnetoreception for European Robin Cryptochrome 4. Curr Biol. 2018;28(2):211-223.e4. doi:10.1016/j.cub.2017.12.003
Fleissner, G., Holtkamp‐Rötzler, E., Hanzlik, M., Winklhofer, M., Fleissner, G., Petersen, N. and Wiltschko, W. (2003), Ultrastructural analysis of a putative magnetoreceptor in the beak of homing pigeons. J. Comp. Neurol., 458: 350-360. https://doi.org/10.1002/cne.10579
Heyers D, Zapka M, Hoffmeister M, Wild JM, Mouritsen H. Magnetic field changes activate the trigeminal brainstem complex in a migratory bird. Proc Natl Acad Sci U S A 2010,107:9394-9399.
Hore PJ, Mouritsen H. The Radical-Pair Mechanism of Magnetoreception. Annu Rev Biophys. 2016;45:299-344. doi:10.1146/annurev-biophys-032116-094545
Foley, L., Gegear, R. & Reppert, S. Human cryptochrome exhibits light-dependent magnetosensitivity. Nat Commun 2, 356 (2011). https://doi.org/10.1038/ncomms1364
Kirschvink JL, Kobayashi-Kirschvink A, Woodford BJ. Magnetite biomineralization in the human brain. Proc Natl Acad Sci U S A. 1992;89(16):7683-7687. doi:10.1073/pnas.89.16.7683
Wang CX, Hilburn IA, Wu DA, et al. Transduction of the Geomagnetic Field as Evidenced from alpha-Band Activity in the Human Brain. eNeuro. 2019;6(2):ENEURO.0483-18.2019. Published 2019 Apr 26. doi:10.1523/ENEURO.0483-18.2019 |
Welcome to Algebra 1!
Moving forward please find all info on Google Classroom. Contact Ms. Auger with questions.
Core Connections Algebra is designed to prepare students for higher-level mathematics courses and give them background to utilize more advanced algebra in their everyday lives. The specific topics include: linear relationships, quadratics, exponentials, inequalities, sequences, as well as functions and relations. This course will stress not only key mathematical skills, but also the importance of problem solving, reasoning, critical thinking, and teamwork. Students will solve, analyze, and critique other students’ ideas as they work together to develop mathematical thought. |
Children & Psychotherapy
Some children really love therapy. They feel they have a trusted ally and like the creative activity. Other children can feel threatened by therapy and make strong complaints about going, even though the therapy may be helpful. If the child complains, parents and the therapist have to determine whether the complaints are part of recovery.
Kids who have gone through significant trauma may need more help in developing the ability to keep out troublesome thoughts and worries. With these children, the therapist needs to be careful not to move too quickly to speak about the painful events because the child can experience this as a repetition of the trauma. Before remembering the painful experience, the child must get permission to forget and take part in living. When the child has developed emotional skills and strengths they can start to remember the trauma, which can be helpful. Being forced to remember too soon can be another painful demand. The child has to feel safe enough and ready to remember the painful experience.
It is important that the parents be committed to the theraputic process and understand that emotions can be stirred up in the process. Parents need to be prepared for what might be a lengthy process.
Basic Concepts and Components of Psychotherapy
For children to flourish, they need to learn certain skills that allow them to relate to other people. They need to know how to express their feelings effectively when interacting with others. Children should be able to experience a wide range of feelings without becoming overwhelmed. In their relationships, children should be able to play cooperatively and competitively with peers. With adults, children should be able to put up with the reasonable demands of authority, and make their wishes and concerns known.
These skills are usually learned in the family setting and early school environment. When children have difficult temperaments or they have a challenging situation at home, it can be hard for them to develop these skills. Beginning psychotherapy early can make a big difference in bringing development back on track. For children, play is the language of the imagination and feelings. Play allows children to express their strongest feelings and conflicts. In this way, play provides an avenue into the child’s inner world. In the context of play, difficult thoughts and feelings can be expressed in a non-threatening way. Play offers a controlled setting where a child can try out new behaviors.
Problematic behavior is often an attempt to manage anxiety and feelings of danger. In psychotherapy, safety is created by the relationship between the child and the therapist. The regular meetings, the therapist’s consistent and careful focus on the child’s worries and the therapist’s acceptance of the child, all add to an increased sense of security. When the family understands the nature of the child’s behavior, it can help them find more effective responses. As things begin to feel safer in their environment, children can take the risk of leaving their old methods of managing anxiety behind, and can begin to develop new, more positive behavior.
It is important for parents to understand that throughout the course of psychotherapy, children may have intense positive and negative feelings toward their therapist. This is part of what allows therapy to reach the child at the deepest level.
Description of a Typical Session
When I work with a child, I begin by meeting with the parents. I gather information about the nature of the child’s difficulties and the family’s background. After getting a history of the child’s development, I meet with the child. Often children will want their parents to stay with them during the first session. As a rule of thumb with younger children I encourage parents to participate in most if not all of the sessions, since I believe that the work that starts in the therapy-room should continue at home. During the session, children are invited to play with the toys and art supplies in the office. As the therapy continues, the child’s worries and concerns are expressed increasingly through play and drawings. As the child starts to trust the therapist, there is room for the therapist to begin to talk with the child about how the themes in the child’s play may be connected to issues and feelings in the child’s own life.
When working with teenagers, I explain to them what I have been told about their situation and ask them to give me their perspective of themselves and their family. Some teenagers are quite ready to speak about their thoughts and feelings. Other teenagers may feel unsure about opening up with a stranger. With these teens, I work hard to create a more comfortable context for discussion. We may begin by speaking about music, movies, images, things they read or write about or other ordinary topics and allow this to become a springboard for more personal conversation. After meeting with the child for several sessions, I will then schedule another meeting with the parents. At this time I will talk to the parents about my impressions and talk about a possible course of treatment. It is important for parents to understand the reason for treatment, and to have a good sense of the commitment involved.
Average time per session last 50 minutes, one to four times a week. Therapy tends to work best when children have at least two sessions a week.
Estimated Length of Time Before Change Can Be Expected
With most children, therapy requires time for enough safety and trust to be established. This process can take a few month and at times it can take up to a year or even longer.
Suggestions to Make Psychotherapy More Effective
Parents should meet with me regularly: once a week to once a month. You shouuld keep me informed about the events in your child’s life. I will coach you on ways to be more effective at home. Parents sometimes have the idea that children should talk about their troubles with the therapists. Parents must realize that, for the therapy to go well, there has to be room for play. Parents should understand that conflict and strong emotions are an important part of the therapeutic process, and that during difficult periods in the treatment they should collaborate closely with me.
Different Methods of Psychotherapy for Children & Youth
There are many different forms of psychotherapy for kids, some of the methods I use are: Psychodynamic, Play Therapy and Expressive Art Therapy.
Areas In which Psychotherapy With Children Can Help
Psychotherapy can help kids with depression and anxiety, as well as with problems at school, attention and learning difficulties, adjustment to loss, divorce, or death, impulse control, defiant behavior and aggression, social skills, peer and sibling relationships, loneliness, history of trauma/abuse or neglect, coping with troubled family members or parents with addictions. |
The human body is home to an estimated 39 trillion microbial cells, mostly in our guts, but also in our mouths. Recently, scientists in the US conducted a study using a novel fluorescent imaging technique that revealed high-resolution maps of the complex microbial communities living on the human tongue.
Image Credit: crystal light/Shutterstock.com
Interestingly, researchers found that microbes living on the tongue are not spaced out randomly, rather, they live in clusters. It appears that microbial species prefer to live close to other microbes of their own species, which forms microbial populations in distinct clusters.
The tongue is home to a large community of microbes
Humans have lived in harmony with numerous species of resident microbiomes for millions of years. The mouth is home to around 700 species of bacteria that live on the teeth, tongue, and other soft tissues, resulting in an oral microbiome that forms a complete, complex ecosystem. Numerous factors impact how microbial communities locate themselves in the oral cavity, such as moisture, oxygen, pH, salivary flow, temperature, and the frequency of abrasions and level of oral hygiene.
Microbes themselves also act as a factor, they can influence their neighbors by acting as sinks of inhibitory molecules (e.g. antimicrobial peptides and hydrogen peroxide), metabolites, and nutrients. Additionally, microbial colonization of one species can physically prevent other microbial species from occupying that space. Finally, microbes present binding sites to which certain microbial species can attach.
While the spatial distribution of microbes on the tongue is complex and important to understanding how these communities work, previous research in the area of microbial ecology has focused on microbial spatial patterning in the oral cavity. Scientists recognized the need to develop a method to measure spatial patterning.
The tongue serves as a traditional reference point for doctors, often, patients are asked to 'stick out your tongue’ during medical evaluations. Gaining a better understanding of the large community of microbes that live on the tongue could be vital to advancing other areas of medicine.
Preserving the spatial structure of microbial communities
Recently, a US-based team of scientists developed an innovative fluorescent imaging technique to produce high-resolution maps of the microbial communities that reside on the tongue. In a paper published in March 2021, the team reveal the images they developed, which demonstrate the highly structured spatial organization of the microbial biofilms on the tongue’s surface.
Combinatorial Labeling and Spectral Imaging -- Fluorescence in situ Hybridization (CLASI-FISH) was recently established by scientists at the Marine Biological Laboratory, Massachusetts, and Brown University, Rhode Island.
The novel technique is capable of labeling distinct microorganisms via the attachment of fluorophores to their surface, allowing them to be visually identified. Some of the same researchers who developed this technique then used it in a new study where microbes on the tongue were labeled, allowing maps of colonizations to be produced in a single field of view.
Previous studies exploring the nature of bacterial communities have mostly utilized DNA sequencing-based techniques. However, to conduct these, samples must first be ground into a powder to extract the necessary genetic information. Via this method, therefore, all information regarding the spatial structure of the microbial communities is lost. Using the new CLASI-FISH technique offers a way of studying this spatial structure while simultaneously identifying the type of bacteria.
Visualizing bacteria on the human tongue
Major bacterial taxa were first identified from small samples of bacteria obtained by scraping the tongues of 21 healthy volunteers. The imaging technique, guided by sequence analysis, was able to identify major genera and targeted species, generating a comprehensive view of the structure of the microbiome. 17 bacterial genera were identified as being highly prevalent on the human tongue and were present in over 80% of participants.
Researchers found that samples held a combination of free bacteria, bacteria attached to the epithelial cells of the host, and bacteria that had arranged themselves into complex, multilayer biofilms.
These multilayer biofilms, or consortia, had spatially localized domains that were dominated by a single species of bacteria. Results showed that the consortia, while they varied in shape, were generally tens to hundreds of microns in length, had a core of epithelial cells, and a perimeter that was well-defined.
All subjects’ tongues had consortia with the following three genera of bacteria: Actinomyces, Rothia, and Streptococcus. The maps produced by the CLASI-FISH technique revealed that Actinomyces often appeared near to the core, Rothia appeared in large quantities toward the exterior, and Streptococcus was often found in the form of a thin crust on the consortia’s exterior, as well as in the form of veins on their interior.
The results of the study are vital to deepening our understanding of the key species of bacteria that make up the oral microbiome. Further to this, the novel CLASI-FISH technique was able to provide detailed information on the structure of the microbiome for the first time.
- Kilian, M., Chapple, I., Hannig, M., Marsh, P., Meuric, V., Pedersen, A., Tonetti, M., Wade, W. and Zaura, E., 2016. The oral microbiome – an update for oral healthcare professionals. British Dental Journal, 221(10), pp.657-666. https://www.nature.com/articles/sj.bdj.2016.865#citeas
- Wilbert, S., Mark Welch, J. and Borisy, G., 2020. Spatial Ecology of the Human Tongue Dorsum Microbiome. Cell Reports, 30(12), pp.4003-4015.e3. https://www.cell.com/cell-reports/fulltext/S2211-1247(20)30271-0
- Valm, A., Mark Welch, J. and Borisy, G., 2012. CLASI-FISH: Principles of combinatorial labeling and spectral imaging. Systematic and Applied Microbiology, 35(8), pp.496-502. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3407316/ |
Kwashiorkor otherwise known as “edematous malnutrition” or “protein malnutrition” is a nutritional disorder caused by the lack of protein in a child’s diet and it is often characterized by extremely thin appearance, changes in skin pigment, loss of muscle mass, etc. The name ‘Kwashiorkor‘ was coined by Jamaican paediatrician Cicely Williams in 1935. It was derived from the Ga language in Ghana.
Kwashiorkor is a common disease in Nigeria that affects many young children they’re over 200,000 cases of Kwashiorkor in Nigeria.
However, the basic aim of this article is to examine this painful health condition, ranging from its common causes, symptoms, treatments of Kwashiorkor, as well as how to prevent its occurrence.
What are The Causes of Kwashiorkor
Protein deficiency is the major cause of Kwashiorkor. The reason is that every cell in your body requires a substantial amount of protein to be able to repair cells and produce newer ones. A healthy human body is that which is able to regenerate cells easily and constantly.
In addition to the above, protein is very essential for growth during pregnancy as well as infancy. When there is no sufficient flow of protein in the body system, the normal body functions will begin to decline, and may later result in kwashiorkor.
However, the cases of Kwashiorkor occurs most frequently in countries where nutritious foods are not in proportional supply, and some of the countries with the highest records of this condition include DR Congo, Malawi, Rwanda, Togo, and Cameroon. The record shows that these countries have some of the highest rates of Kwashiorkor admissions and the average age of the patients ranges from 6 months to 30 months.
On the other hand, Kwashiorkor is rarely recorded in countries where there are abundant foods with high protein content. Even if it occurs in countries like this, it could be as a result of neglect, abuse, fad diets, or HIV.
Some other causes of Kwashiorkor include the following:
- consuming the wrong nutrients
- having a certain health condition that hinders the adequate absorption or processing of nutrients
- imbalanced nutrition
- inadequate knowledge about nutrition
- Kwashiorkor could also be an underlying symptom of HIV.
What are The Symptoms of Kwashiorkor?
Generally, children with kwashiorkor often have edema (excess water retention in body tissues) which makes them look extremely thin and become very weak. Other common symptoms of kwashiorkor include the following:
- Changes in skin pigment
- Loss of muscle mass
- Stunted growth
- Flaky rash
- Loss of appetite
- Lethargy and irritability
Kwashiorkor if not treated for a long time may result in severe health conditions, including permanent physical and mental disabilities, lowered body temperature, enlargement of the liver. If you are wondering if kwashiorkor can kill you a patient, the answer is yes. If the body is starved of protein for a long time, the condition will become deadly.
How is Kwashiorkor Treated?
Remember it was stated earlier that protein deficiency is the major cause of kwashiorkor, hence, the best way to correct this condition is by eating more protein as well as abundant calories.
However, the treatment approach to be taken depends on how severe the condition is; for instance, if it has developed into shock the patient in question must be subjected to a very quick treatment so as to restore his or her blood volume and maintain blood pressure.
Normally, kwashiorkor treatment usually begins by restoring and improving the patient’s energy which is often done by giving him/her some calories in the form of carbohydrates, sugars and fats. After gaining some energy, the patient will then be given foods that contain a substantial amount of protein. For quick and better results, Doctor may also suggest the intake of long-term vitamin and mineral supplementation.
However, it is best to increase the calorie intake very slowly because the body has long been deprived of proper nutrition and thus it may require enough time to adjust to the sudden increase.
Can Kwashiorkor be Prevented?
Yes, Kwashiorkor can be prevented!
The best way to prevent Kwashiorkor is by eating a well-balanced diet; the overall calories must contain a minimum of 10% and 12% of carbohydrates and protein respectively.
Other proven kwashiorkor prevention techniques are as follows:
- Pregnant and lactating women should eat only nutritious foods.
- Breastfeeding should be encouraged over bottle feeding.
- People should acquire more knowledge of what a balanced diet is.
- Parents should only give birth based on their financial capacity.
- Early symptoms of Kwashiorkor should be reported as soon as possible to the doctor.
Can kwashiorkor occur in adults?
Kwashiorkor is mainly common in children and rare in adults. However, Kwashiorkor can also occur in adults, but, the symptoms are a bit different from that of children.
Kwashiorkor is a nutritional disorder majorly caused by protein deficiency, and if it not treated for a long time, it may further result in severe health conditions, including Permanent physical and mental disabilities, lowered body temperature, enlargement of the liver, to mention but a few.
Fortunately, this health condition is preventable; all you need do is to start/keep eating foods that are highly nutritious and also observe other prevention techniques highlighted earlier. There are so many healthy Nigerian foods that contain proteins.
A balanced diet is the key to preventing Kwashiorkor – go for it!
Thanks for reading. Please share and don’t forget to leave a comment below. |
How might the ancient relative of humanity dubbed "Lucy" have given birth? In a manner in between that of chimpanzees and humans, with newborns undergoing a bit of tilting in the birth canal as they were born, a new study finds.
Lucy and other members of her species may also have relied on midwives, researchers said.
These findings could shed light on how modern human childbirth evolved and made way for large brains, scientists added. [Photos: Mysterious Human Ancestor May Have Walked Alongside Lucy]
Modern humans give birth in a way quite different from how their primate relatives do it, according to research described in the book "Human Birth: An Evolutionary Perspective" (1987, Aldine Transaction) by Wanda Trevathan. This is likely because of both the unusually large size of the modern human brain and the way a woman's pelvis is positioned for upright walking, Trevathan wrote. Understanding the way in which human childbirth evolved could also shed light on how unique human traits such as large brains and upright postures emerged over time.
In primate babies, skulls are longer from the faces to the backs of the bodies than compared with from the forehead to the chin or from left to right. In most primates, the birth canal is similarly longer in that direction: lengthwise from the front to the back of a female's body. There is often plenty of room for most primate newborns as they exit the birth canal, so most primate mothers do not need help when they give birth. Instead, "mothers can just reach down and assist with their own births," said study lead author Jeremy DeSilva, a paleoanthropologist at Dartmouth College in Hanover, New Hampshire.
In contrast, in modern humans, the width of the birth canal, extending from the right to the left of the body, is bigger than the length. As such, babies enter the birth canal facing sideways. As the baby's head progresses out of the canal, it rotates to face the mother's back so the shoulders can then fit through. Human babies fit very snugly in birth canals, so human mothers generally require at least some assistance during birth, the study showed.
The absence of complete, undistorted fossil pelvises from female hominins — the group of species that consists of humans and their relatives dating after the split from the chimpanzee lineage — makes it difficult to see how hominin birth canals evolved over time and when rotations might have become common during childbirth, the researchers said. Some scientists have argued that rotation began only when brains became bigger with the human lineage, Homo. Others have suggested that rotation happened with the smaller-brained australopith lineage, Australopithecus.
Australopithecus afarensis is one of the earliest known relatives of humanity that has a skeleton built for walking upright. The species included the famed 3.2-million-year-old Lucy. Members of the Australopithecus lineage, known as australopiths or australopithecines, lived about 2.9 million to 3.8 million years ago in East Africa, and are among the leading candidates to be direct ancestors of the human lineage.
Prior analyses of how early hominins gave birth often focused on the baby's head and the mother's pelvis, with little attention paid to newborn's shoulders, DeSilva and his colleagues said. However, they noted that humans and apes have broad, rigid shoulders, and early hominins likely did as well. Personal experience helped prompt DeSilva to investigate the role that infants' shoulders played in early hominin birth, he said.
"With the birth of my own children, I started to get very interested in how Australopithecus gave birth and parented their children millions of years ago," DeSilva said.
To study these questions, DeSilva's team analyzed the fossil pelvis of Lucy and came up with a mathematical model describing how newborns might have made their way through Lucy's birth canal. "What we found with Lucy was very much in between that of chimpanzees and humans," DeSilva told Live Science.
There are no known fossils of any newborn australopiths. So, the researchers modeled the shape and size of an A. afarensis infant's head by assuming it had the same dimensions as a newborn chimpanzee's head but with a slightly larger size. They made this assumption because the average A. afarensis's adult skull capacity was about 20 percent bigger than that of modern chimpanzees, the researchers said.
In addition, the researchers said they estimated the width of an A. afarensis baby's shoulders by looking at the relationship between the shoulder widths of adult and newborn primates such as humans, chimps, gorillas, orangutans and gibbons, and by examining the width of an adult A. afarensis' shoulders.
"This is the first time the width of the shoulders has been considered in an attempt to reconstruct childbirth in early hominins," DeSilva said. "I'm excited anytime we can take these old fossils and bring them back to life and reconstruct what our ancestors and extinct relatives were doing."
Based on their models, the researchers suggested that, as happens in humans, a baby A. afarensis would have entered the birth canal sideways. However, the researchers also suggested that an infant A. afarensis would have had to tilt only a bit to make way for its shoulders as its head slid down the birth canal, instead of its head rotating 90 degrees as happens with human babies during childbirth.
"I think we have a tendency to think about Australopithecus and about Lucy as being quite ape-like. Sure, they walked on two legs, but in most other ways, we imagine them to be like modern apes," DeSilva said. "For some aspects of their life, this is probably true, but in terms of childbirth, our findings would suggest that they were more like us — not exactly like us, but more like us." [Image Gallery: Our Closest Human Ancestor]
The scientists did note that there was a tight fit between the infant A. afarensis and its birth canal. This suggests that australopiths may have had difficulty during labor just like modern humans, the scientists said.
"Because their mechanism of birth would benefit from having helpers, it paints a picture of Australopithecus as a much more social animal, perhaps helping one another out during childbirth," DeSilva said. "The origins of midwifery may very well extend back over 3 million years."
These findings suggest that the evolution of rotation during birth may have occurred in two stages, the researchers said. First, after hips designed for upright walking evolved, infants started rotating a bit in the birth canal so it could accommodate the head and shoulders. Then, as brains got bigger in the human lineage, full rotation began happening during childbirth, the study said.
DeSilva said that future research can examine what childbirth was like for other hominins, such as Australopithecus sediba, a potential ancestor of the human lineage.
The scientists detailed their findings online April 12 in the journal The Anatomical Record.
Original article on Live Science. |
By Christine Hemelians MS, OTR/L
Picture the younger version of yourself. Now, picture all the times you participated in pretend play as a child; whether it was by yourself, with your friends, or with your parents. Children grow and learn through play. Pretend play provides children opportunities to build a plethora of skills including, but not limited to: fine motor and gross motor skills, self-care skills, social emotional skills, cognitive skills, and language skills. Infants between the ages of 14-18 months will typically partake in pretend or symbolic play with familiar, everyday items (i.e. pretending to feed a doll).
What are some examples of pretend play?
- Playing dress-up
- Dressing up dolls, action figures, or stuffed animals
- Making an airplane “fly”
- Pretending to cook
Why is pretend play important?
Research supports that pretend play enhances a child’s problem-solving skills, social skills, and provides the foundation to allow them to build on their sequencing skills. It also allows children to build upon and enhance their social emotional skills, as well as their communication skills. Pretend play also helps encourage creativity and offers children the opportunity to rehearse social skills and role play different scenarios.
Toys/Activities that promote pretend play
- Cooking and food toys
- Trucks and Blocks (Legos, Bristle Blocks, Mega blocks, Magnatiles, etc.)
- Doctor kits
- Cardboard boxes
- Old clothes and telephone (practice playing dress-up!) |
Also found in: Wikipedia.
voltage regulation[′vōl·tij ‚reg·yə‚lā·shən]
(in power distribution networks), measures taken to maintain electric voltage within specified limits. In modern systems, all processes of voltage regulation in cases of changes in load (or the occurrence of breakdown conditions, such as a short circuit, in individual sections of the network) are performed automatically by special devices, mainly devices for automatic regulation of excitation in electric generators and synchronous compensators.
The change in voltage magnitude that occurs when the load (at a specified power factor) is reduced from the rated or nominal value to zero, with no intentional manual readjustment of any voltage control, expressed in percent of nominal full-load voltage. Voltage regulation is a convenient measure of the sensitivity of a device to changes in loading. See Generator, Transformer |
After the Haitian earthquake there was a much stronger earthquake in Chile, but was much less devastating, because of the difference of Chile having a building codes and Haiti having no building codes. This should be something that is regulated by the government, but most engineers and architects don’t turn in plans for approval because of the understaffed and unequipped department, so most buildings are built with substandard materials and not designed to withstand earthquakes, unlike in Chile where each proposed building and site goes through extensive testing, and licenses engineers, architects and engineers. Because buildings weren’t reviewed many buildings that have supports don’t work to support the building with strong horizontal external forces. The majority of the Haitian population live in Port-au-Prince and over half of the population lives in poverty, so there’s a high demand for cheap housing, this high demand results in “rapid construction with little engineering input”. The reason that this is possible is because of the total absence of the state in Haiti”(Oliver-Smith) Haiti’s government doesn’t have the best reputation when it come to helping the people that elect them(I need to find a source to support my further claims).
The reason that Chile is compared to Haiti is that both of these countries had earthquakes early in 2010. While Chile had an 8.8 magnitude on the Richter magnitude scale and the death toll was approximately five hundred and fifty. As previously stated the earthquake in Haiti was a 7.0 and the estimated death toll is one hundred sixty thousand. Chile has a history of earthquakes, being in the Ring of Fire creates significant earthquakes, such as the 1960 9.5 earthquake and 1985 7.8 earthquake. Following the 1985 earthquake the Chilean government implemented a strict building code. (chilean building codes). Rates their soils into 4 types. One of the reasons that Haiti was so drastic is that the ground soil had few plants and had a high water saturation rate, which is why the ground turned to liquid upon the shaking of the earth.
Ring beams was the most significant change done in Sustainable Housing Reconstruction. The group did more work around the community such as infrastructure such as walkways, underground drainage, lights and sanitation(Charlesworth). Some houses that were damaged but not destroyed were refitted with the necessary modification of the ring beam, which was described more in Li You and Wen Liu’s paper with studied the effects of coal mining on the ground and how people continued to build on the ground that would shift randomly. The effects of coal mining to the quality of the ground is very similar to the ground in Port-Au-Prince which is To continue using building on sites that were being mined, the building needed to use ring beams to resist the potential movement of the ground caused by the effects of mining. They must almost be used in developing buildings since its unsure of when the effects of the mining become minute or the ground becomes stable again. The required ring beams strengthens the stiffness and integrity of the building and improves the building’s ability to resist ground deformation.
An example I found that can be related to type of ground that is in Port-au-Prince and the ground found in China The reason that ring beams in buildings in coal mining areas is so relevant to Haiti is how the coal being extracted from the ground affects how the ground moves. Some measures to continue building’s ability to continue safely housing people with ring beams. (Chinese mining)
“In Analysis on Rationality of Deformation Resistance Structural Component Ring Beam”, which focuses on buildings that are built on mining areas. Because of the mining the land is unstable to building that existed before the mining began or building that were built before ground becomes stable . The term used is confrontation deformation construction. Some of the determining qualities are the location, structure type and size, the deformation types and deformation size. The ring beam strengthens the stiffness of the building and the integrity of the building and the building’s ability to resist the grounds deformation. The buildings that are built on barren material on the after the coal mining is done, the ring beam is a common rigidity protection. The ring beam is combined with the framework of the building. The coal mine grounds move, so this a subdued, man made earthquake, so this is an example of by its so important to be used in earthquake active areas as well as other areas where the framework of a house needs extra reinforcement, such as areas that are affected by hurricanes and tornadoes, but buildings in those areas need to be raised off of the ground to be protected the house from water damage and being dragged away by the force of the water. In the case of tornados there is a room in the center of buildings that has no windows, but no home can withstand a direct hit from a severe tornado.
Following the earthquake in Gujarat in 2001, the city used land reconstruction as part of it’s reconstruction process. This process was first used in Japan and then in Gujarat in India. The process was city level planning which was followed by case studies in the most damaged areas. Outside of Japan this is one of the few examples were land readjustment were land readjustment was successful in reconstruction efforts after a disaster. Land readjustment has landowners combine their land. My source said it’s “characterized by a reduction in lot sizes to create public land and to widen and straighten out streets, plots, and blocks for the purpose of installing physical infrastructure” (Hien 2010). Its most commonly used in the fringe area of cities to transform irregular shaped plots into more usable spots.
Whenever my family donates to a new organization, we like to do research about how much of our donation will actually go towards the efforts we want to support (A good source for this would be Watchman)(“‘Poverty’ has been translated into considerable comfort for some people”) |
Astronomers, using different European Southern Observatory, or ESO, telescopes, have created the most detailed map of the central bulge of the Milky Way. The central bulge, which is the heart of the galaxy, is home to about 10 billion stars, and the new map will help researchers discover the structure of the bulge as well as learn more about its origins.
Depending on the viewing angle, the inner region of the central bulge has an X-shaped, or "peanut-like," structure, notes ESO. Astronomers on Earth cannot view the central bulge directly, as it is obscured by dust clouds, and must measure infrared radiation in order to make any observations of the bulge.
Two teams of researchers used different infrared data, collected by ESO telescopes, to create the new map.
A team from the Max Planck Institute for Extraterrestrial Physics, or MPE, located in Germany, used ESO's Visible and Infrared Survey Telescope for Astronomy, or VISTA, which is part of the Paranal Observatory in Chile, to create the map of the central bulge. The team's research was published in Monthly Notices of the Royal Astronomical Society. The VISTA Variables in the Via Lactea, or VVV, survey observed more than 22 million stars, red clump giant stars whose distance can be easily calculated, within the central bulge.
Lead author Christopher Wegg, said in a statement: "From this star distribution we can then make a three-dimensional map of the galactic bulge. This is the first time that such a map has been made without assuming a model for the bulge’s shape."
The astronomers' work in creating a new map of the central bulge of the Milky Way led to some interesting observations about the bulge's structure. Based on the viewing angle, the inner region of the bulge has a peanut-like shape, when viewed from the side, or a bar shape when viewed from above.
The MPE team was focused on the central bulge's structure while a second team wanted to understand the motion of stars within the central bulge.
Led by Sergio Vásquez, a PhD student from Pontificia Universidad Católica de Chile, the team studied the motion of galactic bulge stars within two arms of the X-shaped structure. The researchers can then use these measurements to determine the accuracy of central bulge models used by astronomers. This study was published in the journal Astronomy & Astrophysics.
According to ESO, astronomers believe the Milky Way was once a pure disc of stars that later developed the bar as stars collapsed inward. The bar structure is what makes the Milky Way a barred spiral galaxy and this structure is commonly found in other galaxies.
Vasquez said in a statement: "The stars we have observed seem to be streaming along the arms of the X-shaped bulge as their orbits take them up and down and out of the plane of the Milky Way. It all fits very well with predictions from state-of-the-art models!" |
As African countries struggle to fight the worst outbreak of Ebola in history, a team at UC Davis is working to identify the next disease like Ebola, before it becomes a pandemic.
Jonna Mazet runs the early warning project, called Predict, based at the School of Veterinary Medicine. Many of today’s emerging diseases come from animals. Scientists believe Ebola, for example, is transmitted when people eat fruit bats that carry the virus. So Mazet is searching around the globe for new viruses carried by animals that humans may not have had much contact with before.
Animals and the Viruses They Carry
There are countless viruses out there in the world. Some that evolved with humans -- so we're the viruses' primary hosts -- and some that evolved to live in other animals. Sometimes the viruses in other animals are able to jump to humans. Those are called zoonoses. And when a zoonosis makes that jump, scientists call it a spillover.
"Throughout history, human beings have been dealing with those spillover events," Mazet says. "Some of those, we really learn how to control." Rabies and hantavirus, for instance, are zoonoses. So are some strains of E. coli. We've learned to vaccinate our dogs, to be careful about rodent control and to wash our hands and food.
Then there are the viruses like Ebola, MERS, SARS and HIV, all of which originally came from animals. Until we learn how to control those viruses, they seem a lot scarier than a bout of food poisoning.
Searching for the Next Pandemic
Learning about emerging threats is part of what Mazet is doing with Predict.
"We want to be able to better equip ourselves and the countries that we work with to identify what might be out there that could cause an outbreak like this Ebola outbreak," Mazet says. "So in order to do that, we need to understand what the hosts are."
She and the rest of the Predict team, with support from the U.S. Agency for International Development are searching around the world, looking especially at animals that can live easily around humans -- like bats and rodents -- and at animals that are closely related to us, like non-human primates. Also of interest are areas where humans are coming into contact with animals in new ways. "We're more susceptible to an outbreak of disease if our systems are not experienced with that virus or pathogen," she says.
For four years, in 20 different countries, they've been testing animals for viruses. So far, they've found more than 800, the vast majority of them new to science.
Preventing the Next Pandemic
After finding the viruses and assessing the risk of transmission to humans, the Predict team works with communities to warn people about local threats. They also work with labs and hospitals to help doctors diagnose a broader range of diseases.
Instead of testing people for a specific disease, doctors can use the methods Predict has developed to look for a family of diseases. Not just a specific strain of Ebola, for instance, but for the the whole family of viruses that Ebola is in. "And then we can do some genetic sequencing to say, is that an Ebolavirus that we expect to be in the region," Mazet says, "or is that another closely related virus that might be the next cause of the next outbreak or pandemic?"
"We want to give doctors better tools," Mazet says. "And to do that we think we need to not be chasing the last flu that was here last year, or the Ebola that was in the neighboring country, we need to be able to look at whatever might be there with a broader eye."
So the approach is, essentially, two-pronged: Search the world for new viruses, and improve diagnostics.
"The goal is you would know about it ahead of time so you could reduce transmission risk," Mazet says, "but you would also be able to recognize it super quickly. So instead of taking months like in this Ebola outbreak, and potentially allowing the outbreak to get out of control, you'd be able to diagnose it and shut it down very quickly."
The Difference Education Makes
Emerging diseases can travel as fast and as far as people can, since they can hitch a ride with us on airplanes. That's what happened with the SARS outbreak in 2003.
"For Ebola, we're really being vigilant and watching out for it," Mazet says. "In the decade since the SARS outbreak, we've learned a lot." How to track patients and passengers, for instance.
Mazet says the knowledge she and others are amassing could someday prove critical.
"It sounds dramatic to say we found these 800 viruses that might cause a pandemic," Mazet acknowledges. "Likely they're not going to cause a pandemic, but if we don't know about them, we aren't watching for them, we can't learn about them and we can't reduce transmission risk." |
The English National Curriculum (2014) states:
‘The overarching aim for English in the National Curriculum is to promote high standards of Literacy by equipping pupils with a strong command of the spoken and written word, and to develop their love of literature through widespread reading for enjoyment.’
The National Curriculum aims to ensure that all pupils:
• Read easily, fluently and with good understanding
• Develop the habit of reading widely and often, for both pleasure and information
• Acquire a wide vocabulary, an understanding of grammar and knowledge of linguistic conventions for reading, writing and spoken language
• Appreciate our rich and varied literary heritage
• Write clearly, accurately and coherently, adapting their language and style in and for a range of contexts, purposes and audiences
• Use discussion in order to learn; they should be able to elaborate and explain clearly their understanding and ideas
• Are competent in the arts of speaking and listening, making formal presentations, demonstrating to others and participating in debate
At Crowle Primary Academy we believe the development of Literacy skills is central to improving a child's life chances. We deliver a high quality English curriculum that gives children the best possible opportunities to become confident, literate, successful members of society. Teachers have high expectations for all children to achieve and enjoy English and to be able to use the skills and rich vocabulary they have acquired in a range of contexts. We strive to ensure all children can communicate clearly in spoken and written form. Rich texts are at the heart of our teaching and a love for reading is promoted throughout the school.
Curriculum and Academy Organisation
At Crowle Primary Academy we place rich texts at the core of English planning allowing teachers to use the text as the context for the requirements of the National Curriculum. The English curriculum is organised into reading and writing and these are taught as whole class sessions based on a core text. English is taught on a daily basis, for at least an hour, although teachers have the flexibility to ‘block’ lessons if they feel this is more appropriate. We have a fully-comprehensive approach to the teaching of English which covers a range of genres and links to topics where appropriate ensuring progression in a range of contexts. Vocabulary, punctuation, spelling and grammar have high status within English sessions. In Foundation Stage and KS1 there is also a daily phonics input and phonics support continues in Key Stage 2 when necessary. Children in Foundation Stage and Key Stage one have guided reading sessions until they have the necessary decoding skills in order for them to access whole class reading sessions.
The Foundation Stage
Foundation stage pupils will experience Communication and Language, and English as part of the seven areas of learning as stipulated in the EYFS. The children have experience of aspects of the literacy programme of study every day, e.g. phonics, shared text work etc. Through careful planning and observations of children, teachers will ensure that foundation stage pupil needs are provided for. Speaking and listening skills are vitally important as they underpin all learning at this early stage. The communication, language and literacy programme of the Foundation Stage children builds on their language starting points. Development of these skills is encouraged through activities such as listening to stories and poems, joining in with rhymes and songs, participating in drama and imaginative play, responding to simple instructions, talking to accompany play, etc. Knowledge about books is developed through activities such as guided reading, one-to-one reading, shared reading, retelling stories and continuous access to a book area. Emergent writing is encouraged through role play and continuous provision areas. As the reception class is part of the Foundation Stage of the National Curriculum, we relate the literacy aspects of the children's work to the objectives set out in the Early Learning Goals, which underpin the curriculum planning for the children.
Speaking and listening
The spoken language underpins the development of reading and writing and supports progress across the curriculum. We ensure that children’s competence and confidence in speaking and listening is continually developed. Children are exposed to a wide range of rich, challenging and varied vocabulary and language across the curriculum. Opportunities to develop speaking and listening skills are embedded throughout the curriculum and pupils are also taught to understand and use the conventions of discussion and debate, taking on a role and drama.
The approaches to the other areas of the English curriculum are detailed in the specific areas below. |
Pushing the limits of its powerful vision, NASA's Hubble Space Telescope has uncovered the oldest burned-out stars in our Milky Way Galaxy. These extremely old, dim stars provide a completely independent reading of the universe's age without relying on measurements of the universe's expansion. The ancient white dwarf stars, as seen by Hubble, turn out to be 12 to 13 billion years old. Because earlier Hubble observations show that the first stars formed less than 1 billion years after the universe's birth in the big bang, finding the oldest stars puts astronomers well within arm's reach of calculating the absolute age of the universe.See the rest:
Q & A: Understanding the Discovery
1. Why are white dwarfs used to determine the age of the cosmos?
- The white dwarfs viewed by Hubble are the oldest white dwarfs residing in the globular cluster M4. Globular clusters contain hundreds of thousands of stars and are among the oldest clusters of stars in the universe. Previous Hubble telescope observations showed that stars first began forming about 1 billion years after the big bang. If that's true, then the oldest stars in globular clusters were among the first grouping of stars.
The oldest white dwarfs in the globular cluster M4 are so faint that astronomers used the Hubble telescope's sharp "eyes" to find them. Astronomers also selected the closest globular cluster to Earth. M4 is 5, 600 light-years away.
Conceptually, the age-dating observation is as elegantly simple as estimating how long ago a campfire was burning by measuring the temperature of the smoldering coals. In this Hubble observation, the "coals" are white dwarf stars, the burned-out remnants of the earliest stars that formed in our galaxy.
Hot, dense spheres of carbon "ash" left behind by the long-dead star's nuclear furnace, white dwarfs cool down at a predictable rate - the older the dwarf, the cooler it is, making it a perfect "clock" that has been ticking for almost as long as the universe has existed.
It wasn't easy to find these objects, even with Hubble's sharp "eyes." White dwarfs are steadily cooling off. As they cool, they get fainter. To pinpoint these increasingly fainter objects, the telescope took many snapshots of the stars in M4. In fact, it took nearly eight days of exposure time over a 67-day period for Hubble to observe M4. By observing the cluster intermittently over a long period of time, the telescope was able to take pictures of the coolestand oldestdwarfs. These stars are extremely feeble: they are less than one-billionth the brightness of the faintest stars that can be seen by the naked eye.
2. Why do astronomers need the Hubble telescope to find white dwarfs? And how did the orbiting observatory find them?
Astronomers believe the universe began in one cataclysmic explosion called the big bang. But they're still searching for clues on how our universe has evolved since then. Knowing the universe's age could help astronomers in that quest, especially in understanding the evolution of our galaxy and solar system.
Though previous Hubble research sets the age of the universe at 13 to 14 billion years based on the rate of expansion of space, the universe's birthday is such a fundamental and profound value that astronomers have long sought other age-dating techniques to cross-check their conclusions.
This approach has been recognized as more reliable than age-dating the oldest stars that are still burning by nuclear fusion, which relies on complex models and calculations about how a star burns its nuclear fuel and ages. White dwarfs are easier to age-date because they are simply cooling, but the trick has always been to find the dimmest and hence longest-running "clocks."
3. Why is it important to know the universe's age?
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Enhancing our domestic preparedness has become a national priority. The TPCN plays an important role in our preparedness. We can help recognize and detect threats and ensure appropriate treatment should an event occur.
Our specially trained staff of doctors, nurses, and pharmacists can respond to calls about medications, human exposures, bioterrorism, chemical spills, or other events involving hazardous materials.
Bioterrorism is the intentional release of germs or other biological substances such as toxins that cause illness or death among people.
Biological agents, such as anthrax, do not cause contagious diseases. Others, such as the smallpox virus, can lead to diseases that can pass from person to person. In some cases, biological agents may not result in immediate symptoms or the symptoms may be similar to naturally occurring illnesses such as a cold or influenza.
Chemical Agents can be inhaled, ingested, or absorbed through the skin. These chemicals can come from contaminated food, water, or air. Symptoms may be immediate and range from a mild irritant to painful skin or lung injury.
For more information about biological and chemical agents, visit: www.dshs.state.tx.us/preparedness/bioterrorism
The action you take depends on the following:
If you are inside, and the event is outside:
- If indoors, stay indoors and turn off all ventilation, close windows and doors.
- Monitor situation through new channels.
If you are inside, and the event is inside:
- If you hear a building or fire alarm, move quickly outside.
- Cover all exposed skin.
- Cover your mouth with a cloth.
If you are outside, and the event is outside:
- Cover all exposed skin.
- Cover your mouth and nose with a cloth
- Call 9-1-1 if an individual is unconscious or not breathing
How to prepare your family
Each family should have a family plan for emergencies, whether they are natural or man-made. For a sample disaster kit, visit the American Red Cross website at: http://www.redcross.org under Disaster Services.
Educate your family so they will know the plan.
Volunteer your services in your community and be trained to help. Consider volunteering to PROTECT TEXAS. To learn more, visit http://www.dshs.state.tx.us/comprep. Click on PROTECT TEXAS Volunteers.
What should the public do for a suspected biological or chemical poisoning?
- Monitor the situation through local radio and television broadcasts.
- Listen for and follow instructions from public health and safety agencies.
- Call the Poison Center at 1-800-222-1222 for treatment or other information.
- Call 9-1-1 if an individual is unconscious or not breathing.
For more information or to schedule a presentation for your friends or community groups, contact a poison center educator at1-800-222-1222. |
Access the Image Gallery to see all images, objects, and documents used in this lesson plan.
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Lesson Plan 1: Lewis and ClarkDiplomats or Soldiers?
- define "diplomat" and "diplomacy"
- identify three goals that President Thomas Jefferson wanted Lewis and Clark to achieve in their dealings with the Indian tribes
"Captains Lewis & Clark Holding a Council with the Indians." Sketch in P. Gass, A Journal of the Voyages and Travels of a Corps of Discovery, 1810
"Captain Lewis Shooting an Indian." Sketch in P. Gass, A Journal of the Voyages and Travels of a Corps of Discovery, 1810
Photograph of Secretary of State Colin Powell from: www.state.gov/secretary/
Excerpts from Jefferson's Letter to Lewis, June 20, 1803 (PDF)
Excerpts from Jefferson's Letter to Lewis, January 22, 1804 (PDF)
Vocabulary Sheet for June 20, 1803, Letter (PDF)
Vocabulary Sheet for January 22, 1804, Letter (PDF)
Analyze the Sketches (PDF)
Map of Louisiana Purchase (PDF)
Overhead Projector for Projecting Visuals
Large Chart Paper for Recording Findings
Display the photo of Secretary of State Colin Powell. Ask: "Who is this man?" (Answer: Secretary of State General Colin Powell). "Where have you seen his photograph before?" (Answer: TV, newspapers, magazines). "In what ways were Lewis and Clark and Secretary Powell alike?" They are alike in at least three ways:
- Secretary Powell is a diplomat who represents the U.S. and talks to representatives of other nations trying to make friendships and agreements in the interest of the U.S. Lewis and Clark were diplomats for the U.S. also.
- Before becoming a diplomat, Secretary Powell was a general in the U.S. Army. Lewis and Clark were also officers in the U.S. Army.
- Secretary Powell works for President Bush. Lewis and Clark worked for President Jefferson.
Tell students: In this unit we are going to learn how Lewis and Clark acted as diplomats (and also as soldiers) representing the United States and President Jefferson to Indian tribes in the West.
- Say to the students: "President Jefferson sent a letter to Meriwether Lewis in the summer before the Corps started the expedition. The letter told Lewis exactly what President Jefferson expected and what the mission was to accomplish. We are going to look at the part of the letter that told Lewis and Clark how to deal with the Indian tribes."
- Distribute (or project) copies of excerpts from President Jefferson's letter to Lewis dated June 20, 1803, and read the letter with the class. A content-vocabulary page is included and may be used to help the students read the letter independently, or the letter may be read/discussed as a whole-class activity.
- Ask the students to respond to these questions in a class discussion and record their answers on a large chart that has these headings:
Jefferson's Directions to Lewis and Clark
Concerning Diplomacy with the Indian Tribes
Tell the Tribes:
Find Out About:
Keep and display this chart for reference throughout the unit.
- how does this letter tell Lewis and Clark to treat the Indian tribes they meet?
- do you see any clues in this letter that suggest President Jefferson sometimes would want Lewis and Clark to act in a less friendly way towards the Indian tribes?
List the ways President Jefferson wanted Lewis and Clark to behave in dealings with the Indian tribes in the correct column on the class chart.
List all the things that President Jefferson wanted Lewis and Clark to tell the tribal leaders in the correct column on the class chart.
List all the things that President Jefferson wants Lewis and Clark to find out about the Indian tribes on the class chart.
Questions for students to consider:
- Why do you think President Jefferson wanted all this information about the Indian tribes?
- What do you think the Indian tribes thought of Lewis and Clark gathering all this information about them? Do you think the Indians were just as curious about Lewis and Clark? Why or why not?
Responses to behave should include:
- be friendly (if the Indians allow)
- be polite
Responses to tell should include:
- tell tribes that United States doesn't intend to hurt them
- tell tribes that the U.S. is strong
- tell the tribes that the U.S. will set up trading posts to trade with them
Responses to find out about should include:
- find out the names of the nations (tribes) and how many people each has
- find out where each tribe lives and hunts
- find out how tribe gets along with other tribes
- find out each tribe's language, traditions, and monuments
- Next, tell the students: "After President Jefferson wrote the above letter to Meriwether Lewis on June 20, 1803, the United States purchased the Louisiana Territory from France in December 1803.The Corps of Discovery was spending the winter at Camp Dubois near St. Louis at that time. The men were encamped at Wood River (just northeast of St. Louis on the east side of the Mississippi) waiting for good spring weather before they set out on their expedition. During that winter of 1803-1804 Captain Lewis was in St. Louis gathering supplies when he received another letter from President Jefferson dated January 22, 1804."
In the second letter, President Jefferson added a new diplomatic mission for the captains. According to the U.S. perspective, much of the region through which the Corps would be traveling was now claimed by the United States because of the land purchase, so the captains were directed to let the Indian nations they encountered know of this new development.
- Project a copy of the letter dated January 22, 1804, and read through it with the students. Initiate a class discussion about the new message President Jefferson asked Lewis and Clark to give to the Indian tribes in this second letter.
After the class discusses the new directive, add to the large classroom chart these statements:
- tell Indian tribes they no longer have Spanish/French fathers
- tell Indian tribes they have a new father and protector (the U.S.)
- tell Indian tribes Americans will set up trading posts for them
This might be a good place to break this lesson.
- Tell the students they will look at two sketches of actual encounters that Lewis and Clark had with Indian tribes. Explain that these sketches were printed in a book written in 1810 by Patrick Gass, one of the men who traveled on the expedition with Lewis and Clark. Explain that Gass described the scenes to an artist who then drew them.
- Project (or distribute copies of) the sketches one at a time. Ask students to look at each sketch and complete the sketch analysis sheet. You may choose to have the students work in groups, pairs, or individually. You may want some groups or pairs to analyze one sketch and some the other.
- When the students have finished their analyses, have them share their responses with the entire class. Information to share about the sketches is given below. It comes from Carolyn Gilman's book Lewis and Clark: Across the Divide.
Sketch #1 is titled "Captains Lewis and Clark holding a Council with the Indians" (1810). Tell the students that, "The uniforms are accurate; the Indian togas are not. The person beside Lewis is probably the translator." The council depicted is possibly the one Oto and Missouri Indians held in the vicinity of present-day Council Bluffs, Iowa. Below is a short excerpt of the speech Lewis gave to the Otos at this meeting:
Children. Commissioned and sent by the great Chief of the Seventeen great nations of America, we have come to inform you, as we go also to inform all the nations of red men who inhabit the borders of the Missouri, that a great council was lately held between this great chief of the Seventeen great nations of America, and your old fathers the French and Spaniards; and that in this great council it was agreed that all the white men of Louisiana, inhabiting the waters of the Missouri and Mississippi should obey the commands of this great chief; He (The great Chief) has accordingly adopted them as his children and they now form one common family with us; your old traders are of this description; they are no longer the subjects of France or Spain, but have become the Citizens of the Seventeen great nations of America, and are bound to obey the commands of their great Chief the President who is now your only great father...
....he has sent by us, one of his flags, a medal and some clothes, such as he dresses his war chiefs with, which he directd should be given to the great chief of the Ottoe nation, .....when you accept his flag and medal, you accept therewith his hand of friendship, which will never be withdrawn from your nation as long as you continue to follow the councils, which he may command his chiefs to give you, and shut your ears to the council of the Bad birds."
Sketch #2: "Captain Lewis shooting an Indian." Tell the students that, "The artist who illustrated Patrick Gass's journal portrayed Lewis's fatal encounter with the Blackfeet this way. Gass was not an eyewitness, since he was making the Great Falls portage at the time. Only three men were with Lewis. The man in the capote is probably intended to be Drouillard." * Note: Captain Lewis shot and killed one Piegan Blackfeet Indian, and Private Reubin Field stabbed another on the return trip in 1806. Lewis and several of the men were away from the rest of the Corps when they had a chance encounter with some Blackfeet Indians. The Blackfeet attempted to take some of the American's horses, and in the resulting conflict, Lewis shot and killed the two Blackfeet. For more information see Ronda's Lewis and Clark among the Indians, pp. 238-244, or Lewis' journal entry about the Blackfeet incident (July 27, 1806, pp. 437-439 in The Journals of Lewis and Clark, edited by Bernard DeVoto.)
- Finally, ask the students how the sketches might have been different if an Indian artist who witnessed the events had drawn them. Hide paintings are used by Plains Indians to depict historic events. Students could draw a hide painting of this event. See the Smithsonian's "Tracking the Buffalo: Stories from a Buffalo Hide Painting" Web site at www.americanhistory.si.edu/hohr/buffalo/index.html for more information.
Extension activity: If students wish, have them draw a sketch as an Indian who witnessed the tribal council (or the shooting) might have drawn it. Have them write a sentence or two at the bottom of what the Indian might have said.
Have a student read from the class chart the diplomatic goals President Jefferson gave to Lewis and Clark. Then ask students if they think Lewis and Clark were always successful in living up to President Jefferson's expectations.
SUGGESTED FORMATIVE ASSESSMENT
- Ask the students to take the role of diplomat Meriwether Lewis, and to write a four-to-five-sentence speech that he might have given to an Indian tribal chief he met on the journey west.
- Have students take the role of the chief to whom this speech might have been given. Write a short paragraph telling what that chief might have thought about it. The option could be allowed to give and respond to the speech orally.
To show mastery of the objectives, student speech should include three or more of the following directives given by President Jefferson:
- The Spanish are no longer your fathers.
- We are your new fathers.
- We are your friends.
- We will protect you.
- We will set up trading posts where you can trade pelts for goods.
- Please tell us the name of your tribe and how many of you there are.
- Please tell us where you live and how far away you travel.
- Please tell us about your language.
- Please tell us about your traditions/monuments
- Please tell us about other tribes you know and how you get along with them.
The response by the chief might include some of these points:
- We have had other fathers, why do we need a new one?
- We can make our own agreements with other tribes.
- Your speech makes it sound like we must have your approval for everything we do, but we have minds of our own.
- We look forward to trading with you.
- We are glad you are going to be our allies in war.
- Thank you for the gifts. |
While Executive Function issues are considered a disability in their own right, they are almost always found in people with callosul issues, autism and ADHD. Executive functions consist of several mental skills that help the brain organize and act on information. These skills enable people to plan, organize, remember things, prioritize, pay attention and get started on tasks. They also help people use information and experiences from the past to solve current problems.
If someone has Executive Function issues (EF), they find it difficult to make and execute plans, complete things on a time schedule, keep track of time. They find it hard to generalize using formerly learned material to solve new problems, or look for more information when needed to solve the problem.
Those with EF issues have a great deal of difficulty multitasking. Contrary to belief, no one actually does/thinks more than one thing in any given time, this is not what multitasking is. Rather thing of multitasking like juggling balls; the ability to quickly switch back and forth between several tasks. This is a primary reason why those with ACC and ASD have extreme difficulty when we are knocked off track from something we may be doing or trying to accomplish. We (innately) realize that "if it is not done now, it may never be" and we might even become angry or belligerent if you interfere with our completion of the task.
There are six discreet tasks or operations that make up EF. They are:
- Analysis, or discovering just what needs to be done.
- Planning on how to handle the task.
- Organizing and breaking down the task into a series of steps.
- Deciding just how much time is needed to complete the task, and setting that time aside.
- Making adjustments when unforeseen things complicate the task
- Completing the task in the allotted period of time.
In a neurotypical individual, these steps may happen in barely a few seconds, but with someone with EF issues they can take far longer or not even complete at all. Deciding what words to use in a conversation, for example, can be as difficult with someone that has EF issues as it would be to plan a trip in the coming days.
There are many signs and symptoms of EF issues...
A child (or adult) can find it difficult to figure out how to begin a given task, or focus so much on the details or the overall task, but cannot do both simultaneously.
We can have difficulty deciding just how much time is needed to perform a task, performing the task too quickly, without attention to detail or slowly with missing steps.
We can find it difficult when others give us feedback on our task, and we will stick with our plan, even when it is obvious it isn't really working.
We can have trouble paying attention, are distracted easily, and loose our train of thought when our task or communication is interrupted.
We need to have the directions repeated many times, being prompted constantly in order to fully complete the task. If we are concentrated enough to perform the task, we have incredible difficulty switching from that task to another, as needed.
May not have the words to express the task in detail, and need prompting and help conceptualizing what something feels like, sounds like or looks like. We remember information and steps better using cues, abbreviations or acronyms.
Now, in what ways does EF issues affect an individual?
- Impulse Control
- Emotional Control
- Working Memory
- Self Monitoring
- Planning and prioritizing
- Task Initiation
- and Organization
There are other "non-mental" related areas that are affected by executive function. Some of those are regulating hand pressure (hand writing); bodily coordination, tending to over or under compensate movements to adapt to surroundings (clumsiness), teeth brushing ( I will tend to either brush too hard and damage my teeth and gums or not have enough pressure and don't get the job done.)
With all of these issues unless an EF problem is identified parents or peers may harshly judge the individual. We might be told we just aren't trying 'hard' enough. Or that we are lazy, or stubborn. Without recognizing EF issues it can be extremely frustrating to the child or adult having them.
I personally relate, especially to the lack of ability to begin a task, even after planning said task. I have trouble regularly brushing my teeth and other hygiene issues, because it is much like navigating a complicated maze. If I have someone prompting me at ever step I function really well, but sans that prompting I wander around the house/around life like a three year old never getting anything done.
I carried a tremendous amount of shame around on my back for years regarding this. The constant battering refrain from my father was "you just aren't trying hard enough," or "you're lazy, why can't you be like 'everybody else? ' " Even today as an adult, while my conceptual understanding of these issues is strong, I can't simply relate them to everyone I come in contact with, so I am called "retarded" or "stupid", "bullheaded" or "lazy" by those who do not understand.
With EF issues, it takes more brainpower for us to get through one single day, than it would comparatively take an NT to get through a 7 day week. Just communicating, just functioning for one day can be patently exhausting.
There are many methods that can assist in EF, they don't all work, and not all the time, but they can improve quality of life. My own EF issues are complicated by intrusive thoughts, something common to all with ACC, a constant dialogue going on in my brain, overthinking every tiny small thing into an intricate web of thoughts and ideas. I take a low dose anti-psychotic called Respiradal that helps slow down these intrusive thoughts, and that does help my executive function. The catch 22 is that too much of this can also interfere with EF.
So, this post is really "a day in the life of" me, what I go through daily, and what likely or ACC or ASD or ADHD child or adult friend or family member goes through in every moment of their lives.
Thanks for listening, I hope this has been helpful. It is important for educators and doctors to take these things into account, for parents to take them into account, especially at IEP meetings and other times they need to advocate for their little one(s). |
The Middle School visual arts program begins with an emphasis on exploration, manipulation, and enjoyment of art materials. Students then learn to focus on developing a better understanding and working knowledge of the seven elements of art: line, color, shape, value, form, texture and space. These elements serve as the basic language of the arts and are an important step in understanding the process of creating a successful work of art.
From there, students develop a greater understanding of the eight principles of design: harmony, rhythm, gradation, variety, unity, balance, proportion, and movement. The concepts are abstract, and students face the challenge of organizing these elements in an orderly and harmonious way.
In the final stage of development, students seek to weave together the elements and principles of art and design. Five substantial projects cover a broad range of materials and themes. More is expected in the way of craftsmanship, creativity, and originality.
The goal of the program is to prepare students for the rigors and focus of the Upper School art program, which represents a highly individualized and developmentally-based curriculum. |
KHU - An ancient Egyptian fan surmounted by a single ostrich feather (as seen above highlighted in red), signified "protection" and "breath of life"
For more information about fans in the fascinating Ancient Egyptian world.. read on like an Egyptian.
Fans and Sunshades in Ancient Egypt
In old movies about kings and ancient times, one often finds, standing behind the throne, or walking in the footsteps of a king or queen, a fan carried by a servant. The fan bearer is usually an insignificant part of the scene. But in ancient Egypt, almost every object seems to have a symbolic message, and the symbolic nature of sunshades and fans was especially important. Furthermore, they could also be used as standards for various purposes.
The title of fan-bearer (fan-bearer to the right of the king) was an important one, though this official might not be the actual person carrying the fan.
Ancient Egyptian fans and sunshades often differed only in size. Large sunshades, used to protect one's eyes from solar glare, or perhaps even symbolically to protect onlookers from the brilliance of the king or another high official, were doubtless also used as fans, and the hieroglyphic sign acted as a generic determinative used for words representing both objects. In all periods, the most common types of fan were lotiform and palmiform, imitating the leaf of the blue lotus or the frond of the date palm. Other, less frequently found types were patterned after the leaves of other plants, bird wings and such objects were all doubtless used as fans. An actual example of the type of fan represented by the hieroglyph was found in the tomb of Tutankhamun.
The double deity Hepui seems to have represented the two fans shown accompanying the king in representations from the earliest times, as in the "Scorpion Macehead", named for the scorpion hieroglyph which appears next to the king (King Scorpion), and which may represent his name. There, the fan bearers stand directly behind the king in what is evidently a scene depicting an important ritual event.
Because the fan represented the air it moved, it was an active, functional symbol of breathing and therefore of life itself. In fact, several types of fan were known by the term nefet, meaning "blower," and the symbolic content of this idea could be represented iconographically in a number of ways.
Frequently in Egyptian art, the fan is shown held behind the person of the king not by actual attendants, but by partially personified ankh signs, whose arms hold the fan aloft. In the gold chest ornament of Amanemhet III the king is shown in the ancient ritual pose of smiting the enemies of Egypt, or returning from the hunt, and the fan-wielding ankh signs in attendance clearly spell out the symbolic message that the "breath of life" (ankh) is with the king.
The fan also seems to have suggested the giving of life or life-giving fecundity in a different way. In its function of "blower" the fan could represent the sending forth of life-giving waters of the Nile. Although this image may have developed as a part of Osirian beliefs in alter times, it is possible that even as early as the Scorpion Macehead the fans attending the king represented the sending forth of the waters with which the king's agricultural activity seems to be concerned. By virtue of its shadow the fan or sunshade also represented the "shadow" which, like the soul, heart and name, was regarded as part of the composite human individual. This use of the fan is seen in New Kingdom funerary works such as the Book of Caverns where the hieroglyph appears atop the heads of certain beings and alongside ba birds which worship the image of the sun.
The short-handled khu fan surmounted by a single ostrich feather, with a papyrus-umbel handle, also appears frequently in Egyptian art, carried by the "fan bearer at the king's right side," or by the royal falcon (Horus), vulture or winged wedjat eye in attendance on the king or on a deity such as Osiris. It had the same phonetic value as the fly-whisk and could stand hieroglyphically for "protect," and royal guards may have carried it for this reason. It, too, could represent the "breath of life" when held by Isis, Nephthys or Horus, who waved it over the corpse of Osiris in order to revive him. |
More Geometry Lessons
In these lessons, we will learn
- how to calculate the surface area of a cone when given the slant height.
- how to calculate the surface area of a cone when not given the slant height.
- how to solve word problems about cones.
- how to derive the formula for the surface area of a cone.
Surface Area of a Cone
A cone is a solid with a circular base. It has a curved surface which tapers (i.e. decreases in size) to a vertex at the top. The height of the cone is the perpendicular distance from the base to the vertex.
The net of a solid cone consists of a small circle and a sector of a larger circle. The arc of the sector has the same length as the circumference of the smaller circle.
The following figures show the formula for surface area of a cone. Scroll down the page if you need more examples and explanations.
Surface area of cone = Area of sector + area of circle
Surface area of a cone when given the slant height
A cone has a circular base of radius 10 cm and a slant height of 30 cm. Calculate the surface area.
Area = πr(r + s)
= 1,257.14 cm2
How to find the surface area of a cone when the slant height is given?
What is the surface area of the cone? Round the answer to the nearest hundredth.
Surface area of cone when not given the slant height
The following video shows how to find the surface area of a cone when not given the slant height.
How to calculate the surface area of a cone when the slant height is not given?
The Pythagorean Theorem will be used to calculate the slant height using the radius and height of the cone as the right triangle's legs.
Word Problems about cones
Example 1: A cone-shaped roof has a diameter of 12 ft. and a height of 8 ft. If roofing material comes in 120 square-foot rolls, how many rolls will be needed to cover this roof?
Example 2: The height of the Pyramid of Menkaure is 216 ft and the side of the (square) base measures 346 ft. Find the lateral surface area.
Find the surface area of a composite figure that consists of two cones and a cylinder
Derive the formula for the surface area of a cone
This video shows the derivation of the formula for the Surface Area of a Cone.
How to derive the formula for the surface area of a cone?
In this lesson, we'll take a cone, slice it, squash it, dissect it, and figure out a formula for its surface area.
Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget, a free math problem solver that answers your questions with step-by-step explanations.
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Located in east-central Kentucky where the rolling hills of the Bluegrass meet the foothills of the Appalachians, the land encompassing Madison County has had a long history. The largest county in the Bluegrass, it contains 446 square miles and ranks twenty-first in size among Kentucky's 120 counties. Four geographic regions provide such distinct differences in soil, elevation, and topography that the history of the county is as much a consequence of the geographical features as it is a product of the endeavors of its people.
Centuries before the entry of European settlers, this physiographically varied land provided food, shelter, and safety to human inhabitants. For thousands of years prehistoric peoples roamed the hills, hunted game along the creek bottoms, fished in the many streams, and eventually cultivated food in the fertile valleys. By the seventeenth century the American Indian tribes of the Shawnee, Cherokee, and Wyandotte hunted throughout the Kentucky River basin area.
As the entrance-way for the white settlement of land beyond the Appalachians, Kentucky was accessible from the south by mountain gaps and from the north by waterways. The same was true on a smaller scale for Madison County. The Kentucky River which forms the north and northwest boundaries of the present-day county was a major source of transportation and communication, providing passage to the land from the Ohio River. Despite the river access, the earliest routes into the county were from the passable southern terrain along creeks, such as Muddy Creek, Paint Lick Creek, Otter Creek, and Silver Creek that flow northward to the Kentucky River.
Information for this article came from Lavinia H. Kubiak's Madison County Rediscovered: Selected Historic Architecture (1988) |
A ‘dynamo’ in their interior – a metallic core surrounded by several different, rapidly rotating layers, drives the magnetic fields of Earth and several other planets in the Solar System. Earth’s deepest interior creates a field that protects it from permanent bombardment by high-energy particles from the Sun – the solar wind – and cosmic radiation. Many celestial bodies and planets, such as Mars and Venus, do not have a magnetic field. As a result, the magnetic field of the Sun can impinge unhindered on their surface or upper atmosphere.
Surfaces or ionospheres can be simulated with the experimental core of MFX. The ISS provides ideal conditions to study such phenomena – the space station travels across Earth’s magnetic field at 28,000 kilometres per hour. This cannot be reproduced in any laboratory on Earth. The technology experiment was successfully commissioned in 2014 during Alexander Gerst’s Blue Dot mission and, since then, has been investigating, in various ways, the fundamental physics of the above-mentioned interactions.
MagVector/MFX was developed and constructed by AIRBUS on behalf of the DLR Space Administration with funds from the Federal Ministry for Economic Affairs and Energy (BMWi). During the horizons mission, MFX-2 will be equipped with advanced sensors and operated with various material samples – for example, nickel-iron meteorites and chondrites. This extension enables the simulation of even more celestial bodies as they move through the magnetic field. The DLR Institute of Planetary Research is supporting the campaigns scientifically.
MagVector/MFX could also contribute to the development of magnetic shields to protect against charged, high-energy particles, which are necessary for Solar System exploration missions. In addition, the findings will be fundamentally important for the development of all-electric aircraft. |
|Mathematics - Numeration|
|100 Day | Number Sense | Chalkboard Activites|
Books to Read:
|Number Sense and Numeration|
What's My Number - Uses a number line and a game similar "to 20 questions." Teacher draws a number line, thinks of a number, students try to discover what number he/she is thinking of by asking greater than/less than questions
Additional Grab Two - a fun game involving addition
Counting by 2s, 5s, 10s
Have the children sit in a circle.
Count by tens, let's say. Each child says one
number....10, 20, 30,.....to 100. The child who
says 100 is out. Play continues until there is one
child left. I do it by fives to 50, and by twos to
20, but it also can be extended. The kids love it,
and are hearing the counting over and over again.
You can also easily spot the children who don't know it.
We play the same game except we do it
that anyone who is on a 10 is out. It works great
for all skip counting since you do 10's in all of them.
So if you are counting around in a standing circle - 2, 4,
6, 8, 10 - the child who said 10 is out - they sit down
in their spot - keep going - 12, 14, 16, 18, 20 - that
child is out. It's funny to watch because you see
them trying to figure out where they are going to be and
some of them figure out they'regoing to be out - it's so
Even and Odd Numbers - . When doing even/odd
numbers, I used the book Even Steven and Odd Todd
to introduce even and odd numbers. Then we made a booklet
with half even numbers (ex. 2 dogs, 4 bells, etc.) and
flip the booklet over and all those pages had odd numbers.
Mrs. Ritter's First Grade Critters http://www.myschoolonline.com/md/20646_ritter
|Throughout most of the year, we do McCracken
Spelling excercises on chalkboards each morning.
Following the spelling, we do some math exercises while
the chalkboards are still out. Some activities are listed
In this activity the children must determine if they are to add or subtract.
When solving addition facts (e.g., 9 + 5), the students are encouraged to add on from the larger number. I tell them to put the 9 in their heads and count on five more. To practice this skill, which is difficult at first for many students, we practice on the chalkboards.
Option: If you have the students sitting in groups at tables, you can make this a game. Following each question, give 1 point to the table who is finished first ( you will know, because every student at the table will have their hands on their head). At the end of the activity, the table with the most points is the winner.
. Have ready several towers of unifix cubes grouped in tens and some in ones.
Option: To begin the activity have the children draw a line down the center of their chalkboards and write tens on one side and ones on the other side. They will record their numbers in the appropriate columns.
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Electronic Numerical Integrator And Computer, better known as ENIAC was the first multipurpose computer in history. There had existed a few computers prior to it, but all of these though had been built to perform a single task. The ENIAC was not programmable as we think of in today’s terms, but could be used to make general calculations. It was also the first computer to be able to perform the IF statement. Although it was not a complicated IF statement it was very useful. Another revolutionary trait of ENIAC is the fact that it was exceedingly faster than any of its predecessors. This was the most useful thing about it because any computer before it might take 40 hours to do a calculation it could do in less than a minute.
John Mauchly had a lot of interest in creating a calculating machine. However, his colleagues, who said that it could never happen, laughed at his theories. Eventually Mauchly would meet John Atanasoff who would show Mauchly his Atanasoff-Berry machine. It was a special purpose machine and was also very slow. This Machine might have helped inspire Mauchly to work harder on his computation machine since he now knew one existed and how it worked.
Mauchly wanted to learn more about the latest electronic devices and machines so he went to Penn University also know as Moore School. Consequently he was hired as a teacher as many of the existing professors had been called away for World War II. Here is where he met J. Presper Eckert, known as "undoubtedly the best electronics engineer in the Moore School". He was only in his early twenties, and Eckert was a graduate student at the school. Eckert and Mauchly had plenty of time to discus the electronic computing device Mauchly wished to create as they worked together. Eckert said that it was possible to do this. Eckert then produced a memo called "The Use of Vacuum Tube Devices in Calculating.” This memo eventually reached the military, who would decide to sponsor their research out of need for faster computation.
The Military was one of the main reasons that this project happened. Calculations were needed to find the trajectories for certain weapons, and the current calculators could not keep up with the demands. When they found out Eckert and Mauchly already had the idea and plans for an electronic calculating device but lacked the funds.
Captain Herman Goldstine realized this and was able to present the concept to his superiors. A proposal was submitted to the Ballistic Research Laboratory. Eckert and Mauchly kept on producing arguments to support their work. On June 5, 1942 an agreement was made and the computer was named Electronic Numerical Integrator And Computer. They worked on the project in secret. No papers were published and discussions were limited. The computer was never finished in time to help out with the war, but still became quite useful when it was finished.
The hardware of the computer consisted of twenty accumulators. Each contained ten decade counters, which could hold ten digits each. One of the problems encountered when developing the computer was creating a reliable decade counter. Four different decade counters were tested during the development of ENIAC. Each accumulator when they worked properly could store both positive and negative numbers up to ten billion.
Another problem that they had was with the vacuum tubes. They needed the vacuum tubes to carry information. Most vacuum tubes were not very dependable though. If there were 17,480 tubes operating at a rate of 100,000 pulses per second it was calculated there would be 1.8 billion chances of a failure occurring each and every second. Thus much testing went on to find dependable vacuum tubes. Eckert went through and tested and found out why each vacuum tube failed in order to find a way to increase the life of each tube. Even one small glitch could affect the calculations largely and render it useless. Much caution had to be taken in order to prevent any glitches when soldering to make sure the tubes were preserved perfectly.
The IF statements in ENIAC were not great, but did exist. They worked in a very simple way. If the digit that is transmitted from the digit terminal was not zero, a given branch would be triggered. If the digit was zero, the branch would remain un-triggered. It was simple but helpful. If you wanted to check if two numbers were equal or not it could be done, where as it couldn’t previously.
ENIAC also contained ten steppers which could be used for creating loops. Each stepper can be associated with and output port. The output port can be routed as input at looped as many times as desired. It actually was more complicated than that. Since I did not comprehend how they worked that well I will not attempt to explain it to you.
There were a total of twenty accumulators in ENIAC. This meant that it could store up to twenty ten-digit numbers. On top of the ten digits, each accumulator held a sign for whether the number was positive or negative. It also could perform addition. From the use of addition subtraction, multiplication, division and square roots were also possible. There was no central memory so storage was limited to these twenty slots.
The ENIAC was not programmable because it did not have a memory. Its creators wished to make it programmable but only would do so as the creation of the ENIAC would allow. When it was finished it was only programmable be means of switches, cables and pulses. It could not store more that what was in it accumulators. Execution was done by setting the switches manually then turning it on. In its later years, Dr. John von Neumann had developed a way to convert the digit pulses of ENIAC to programming pulses.
In 1946 is was disassembled and moved to Aberdeen Proving Ground in 1947 where it was reassembled. Its maintenance was difficult there as there were thousands of components to maintain. Research and testing was done on the vacuum tubes. This information led to vast improvements on vacuum tubes themselves.
Over its life ENIAC was used for many calculations. It served the Navy and Air Force by making computations for them. It made many of the calculations needed in the creation of the hydrogen bomb. A list of some of its other uses included weather prediction, atomic-energy calculations, cosmic-ray studies, thermal ignition, random-number studies, and wind-tunnel design, among other scientific studies. By about 1953 EDVAC and ORDVAC had both been created and were beginning to take some of the workload from ENIAC.
Dr. John von Neumann had his part in its upgrades. He suggested a way to leave the cables on the machine in place. They could then input data using switches. This saved a lot of time an also caused a lot less error. Other technologies that had been developed elsewhere were added to the machine. It was equipped with a new function-table selector, a special memory-address selector, and special pulse-shaping circuits. These all went along with the new memory that it had been given.
Eventually it was decided that the cost of operating ENIAC was far above its worth. The other computers could handle its workload and were much less expensive to operate. As it lost its usefulness at 11:45 p.m. on October 2, 1955, the power to ENIAC was removed. Efforts were made to preserve it by Dr. von Neumann. Some of its parts still exist in museums today. |
The Galaxy Evolution Explorer (GALEX) is an orbiting space telescope observing galaxies in ultraviolet light across 10 billion years of cosmic history. A Pegasus rocket launched GALEX into orbit at 8 a.m. EDT on April 28th, 2003. Although originally planned as a 29-month mission, the NASA Senior Review Panel in 2006 recommended that the mission lifetime be extended.
GALEX’s observations are telling scientists how galaxies, the basic structures of our Universe, evolve and change. Additionally, GALEX observations are investigating the causes of star formation during a period when most of the stars and elements we see today had their origins.
Led by the California Institute of Technology, GALEX is conducting several first-of-a-kind sky surveys, including an extra-galactic (beyond our galaxy) ultraviolet all-sky survey. During its mission GALEX will produce the first comprehensive map of a Universe of galaxies under construction, bringing us closer to understanding how galaxies like our own Milky Way were formed.
GALEX is also identifying celestial objects for further study by ongoing and future missions and GALEX data now populates a large, unprecedented archive available to the entire astronomical community and to the general public.
Scientists would like to understand when the stars that we see today and the chemical elements that make up our Milky Way galaxy were formed. With its ultraviolet observations, GALEX is filling in one of the key pieces of this puzzle. |
The caterpillar is all but invincible. It has bright warning colours that deter any birds which might want to eat it. It releases foul odours that deter hunters like beetle larvae, which rely more on scent. And it carries toxins that would make good on its threats. It’s a shame, then, that this caterpillar is dead. Its defences are the result of the creatures that killed it—an alliance between a parasitic worm and a glowing bacterium.
When the nematode worm Heterorhabditis bacteriophora burrows into an insect, it vomits out thousands of glowing bacteria, Photorhabdus luminescens. These release toxins that kill the insect and break its tissues into a nutritious soup, which the worms consume. The bacteria also make amino acids that the worms need to reproduce, and antibiotics that kill other microbes that might colonise the insect or decompose its corpse. (During the US Civil war, the same bacteria sometimes contaminated the wounds of soldiers, giving them an eerie blue shine while also protecting them from infections—they called it the “angel’s glow”.)
With the help of their bacterial allies, the worms grow within the dead insect, feeding, mating, and breeding. Eventually, their offspring burst out, suck up their own supply of killer bacteria, and head off to find their own hosts.
This takes around 20 days. During that time, the worms are exquisitely vulnerable: They will all die if a predator scavenges the insect host. And since the insect, being dead, is in no position to defend itself, the worms have to take over. They must protect the very body that they themselves killed. They must save it from being eaten from the outside so that they have enough time to eat it from the inside.
Again, their bacterial allies help. They produce toxins that can deter or kill ants, wasps, beetles, and other scavengers. And perhaps more importantly, they help to advertise these defences.
In 2011, Andy Fenton from the University of Liverpool found that the worms use pigments produced by the bacteria to paint their dead insects in warning colours, making them look as unpalatable as possible. As I wrote at the time, infected caterpillars start off as orange but soon take on a bright pink-red hue, which becomes more intense as the infections continue. This colour change was enough to deter robins, which hardly ever ate infected caterpillars but happily chomped down on healthy ones that had been dead for the same time.
Now, Fenton, together with Rebecca Jones and Michael Speed, have shown that the worms also release a pungent smell. They noticed it themselves: Even to their noses, infected insects stank in a way that uninfected individuals never did. Predatory ground beetles could tell the difference, too. When given a choice between the scents of infected and uninfected caterpillars, wafting out of separate jars, they almost always headed towards the uninfected smells.
It makes sense to produce warning smells as well as colours. The former can deter sight-oriented predators like birds, while the latter can put off smell-focused beetles, or foragers that operate at night. The colours also take several days to make, while the smells can be released soon after the infections begin, providing an earlier line of defence.
Indeed, there may be even earlier defences that the team haven’t discovered yet. Does the brief glow that the bacteria emit have a protective role? And since the bacteria produce light, toxins, off-putting odours, and warning colours, how do they prioritise between these different defences, given that each one takes energy to produce? |
Performance is completion of a task with application of knowledge, skills and abilities. In work place, performance or job performance means good ranking with the hypothesized conception of requirements of a task role, whereas citizenship performance means a set of individual activity/contribution (prosocial organizational behavior) that supports the organizational culture. In the performing arts, a performance generally comprises an event in which a performer or group of performers present one or more works of art to an audience. Usually the performers participate in rehearsals beforehand. A performance may also describe the way in which an actor performs. In a solo capacity, it may also refer to a mime artist, comedian, conjurer, or other entertainer.
From Middle English performen, parfournen (“to perform”), from Anglo-Norman performer, parfourmer, alteration of Old French parfornir, parfurnir (“to complete, accomplish, perform”), from par- + fornir, furnir (“to accomplish, furnish”), from Frankish *frumjan (“to accomplish, furnish”), from Proto-Germanic *frumjaną, *framjaną (“to further, promote, accomplish, furnish, carry out”), from Proto-Indo-European *promo- (“in front, forth”), *per- (“forward, out”). Cognate with Old High German frummen (“to do, execute, accomplish, provide”), Old Saxon frummian (“to perform, promote”), Old English fremman (“to perform, execute, carry out, accomplish”), Gothic 𐍆𐍂𐌿𐌼𐌾𐌰𐌽 (frumjan, “to promote, accomplish”). See also frame, from.
perform (third-person singular simple present performs, present participle performing, simple past and past participle performed)
to be checked
From pre- + form.
preform (plural preforms)
preform (third-person singular simple present preforms, present participle preforming, simple past and past participle preformed) |
An Apollo 17 Panorama
Credit: Apollo 17 Crew, NASA
Explanation: What would it be like to stand on the surface of another world,
to look all around you, and to try to figure out how this world got there?
To get an idea, scroll right. In 1972 during the Apollo 17 mission,
astronauts Harrison Schmitt and Eugene Cernan found out first hand.
In this case, the world was Earth's own Moon. In one of the more famous
panoramas taken on the Moon, the magnificent desolation
of the barren Moon is apparent. Visible are rocks, hills, craters,
the lunar rover, and astronaut Schmidt preparing to take a soil
sample. A few days after this image was taken, humanity
left the Moon and has yet to return. An interactive version of
the above image can be found here.
(I separated the text in lines, otherwise it would just go on and on till the end of the picture.) |
1. The early societies used the full moon as a measure of time. Time from one sunrise to the next was one day and from one full moon to the next was a larger unit. This system came in before the units of 7 day week and 365 day year came into being.
2. Very early in prehistory sea voyage had started. When they were far from shore for days the only direction for them were the position of stars and constellations in the night sky.
View Question Answers |
Medical emergencies involving seizures seem to be a common cause for the dispatch of Emergency Medical Services and despite local treatment protocols, First Responders, Emergency Medical Technicians, and Paramedics remember the basics of their training. Aside from crew safety, airway, breathing, and circulation are the first priorities of any Paramedic and Emergency Medical Technician. Once airway, breathing, and circulation are under control, the next step is to fully assess the patient and administer medications per local protocol in attempt to stop the seizure.
However, what if the medical emergency involving seizures is not a typical presentation EMS responders are used to? What if the medications that are being administered are not working? Could there be another unknown cause? In other words, Dravet Syndrome is a rare genetic disorder affecting one in every 30,000 births.
Dravet Syndrome is also known as severe myoclonic epilepsy of infancy. The Dravet Syndrome Foundation defines it as "a progressive disorder characterized by multiple seizure types, often including life-threatening status epilepticus (prolonged seizures that require emergency care.)"
Various conditions associated with Dravet Syndrome includes "behavioral and developmental delays, movement and balance issues, orthopedic conditions, delayed language and speech issues, growth and nutrition issues, sleeping difficulties, chronic infections, sensory integration disorders, disruptions of the autonomic nervous system (which regulates things such as body temperature and sweating)" (Dravet Syndrome Foundation).
So what does this mean for emergency medical responders and bystanders? Ask someone to call 911 while you stay with the patient. Airway, breathing and circulation are all imperative to life sustainability. According to the American Heart Association 2010 CPR Guidelines, the first step an EMS responder or bystander should do is open the patient's airway and check for breathing. If patient is breathing, make sure they are breathing adequately by looking at their chest for a rise and fall motion.
In an event where the patient is not breathing, check for a carotid pulse. If a pulse is present, pinch patient's nose and begin rescue breathing with a mask or a barrier device with one slow breath every three seconds for pediatrics while looking for that chest rise and fall. Keep assisting with the rescue breaths until help arrives. If the patient is breathing adequately, stay with the patient until help arrives.
With this in mind, bystanders are the initial first responders in any medical emergency. If you witness someone experiencing an emergency, ask if you may assist them and how you may be of assistance. Simply waiting with them for help to arrive can calm a person's nerves. The less anxiety a patient experiences, the better they may feel. |
Labor contractions are the periodic tightening and relaxing of the uterine muscle, the largest muscle in a woman's body. Something triggers the pituitary gland to release a hormone called oxytocin that stimulates the uterine tightening. It is difficult to predict when true labor contractions will begin.
Contractions are often described as a cramping or tightening sensation that starts in the back and moves around to the front in a wave-like manner. Others say the contraction feels like pressure in the back. During a contraction, the abdomen becomes hard to the touch. In the childbirth process, the work of labor is done through a series of contractions. These contractions cause the upper part of the uterus (fundus) to tighten and thicken while the cervix and lower portion of the uterus stretch and relax, helping the baby pass from inside the uterus and into the birth canal for delivery.
How Contractions are Timed
Contractions are intermittent, with a valuable rest period for you, your baby, and your uterus following each one. When timing contractions, start counting from the beginning of one contraction to the beginning of the next.
The easiest way to time contractions is to write down on paper the time each contraction starts and its duration, or count the seconds the actual contraction lasts, as shown in the example below. Writing down the time and length of the contraction is extremely helpful for describing your contraction pattern to your physician, midwife or hospital labor and delivery personnel.
|TIME CONTRACTION STARTS||DURATION OF CONTRATION|
What Contractions Feel Like
Many mothers describe contractions that occur in early labor as similar to menstrual cramps, or as severe gas pains, which may be confused with flu symptoms or intestinal disorders. Imagine your contractions as looking like a wave. Each contraction will gradually gain in intensity until the contraction peaks, then slowly subside and go away. As your body does the work of labor, it is likely that the time in between contractions will become shorter.
As the strength of each contraction increases, the peaks will come sooner and last longer. There should be some regularity or pattern when timed. Persistent contractions that have no rhythm but are five-to-seven minutes apart or less should be reported to your physician or midwife.
Try to visualize contractions as positive
Think of each contraction as something positive—it is bringing you that much closer to the birth of your baby. Visualize what the contractions are accomplishing, the thinning and opening of the cervix and the pushing of the baby downward. Try to work with your body rather than against it by staying as relaxed as possible during the contractions.
Typical Length or Duration
A typical labor for a first time mother is eight-to-fourteen hours, and is usually shorter for a second or subsequent birth. For many women, rocking in a chair or swaying during a contraction assists them with this relaxation. |
Silicene, a single-atom thick layer of silicon, could beat graphene to the components market due to the industry’s familiarity with silicon and its properties.
Graphene is a truly wondrous molecular structure. Since its discovery a few years ago, scientists have become more and more excited about the possibilities graphene affords. It is the most conductive material in the known universe with surprising optical qualities, and IBM has shown that graphene could allow computers to operate close to the terahertz range (one terahertz, or THz, is equal to roughly 1,000 gigahertz, or GHz). The problem is that graphene does not have a band gap. A band gap is the difference in energy from an on state, where electrons are flowing through a circuit, and an off state, where no electron motion is possible. Without a band gap, it’s extremely difficult to build transistors, which have to be able to switch from “on” to “off” and back again very quickly. Some progress in creating a band gap in graphene has been made, but the material is still years or possibly decades away from being used in current computer components.
Now, research has been released from multiple research groups around the planet announcing the creation of silicene, a one-atom thick layer of silicon equivalent to graphene. This presents a lot of promise to researchers and engineers, because silicene, being based on silicon, should be compatible with current electronics and electronic fabrication techniques. The research groups created the silicene sheet by condensing silicon vapor onto a silver substrate. Currently, we only have proof that silicene exists, as the scientists observed it through a scanning tunneling electron microscope, but they theorize that silicene should have highly desirable electrical properties, perhaps even close to the electrical conductivity of graphene.
The next step is to grow silicene on an insulator, so that it can be used to create a circuit. At least four research groups managed to successfully create silicene on a silver substrate, so it’s highly likely that they’re working to find an insulator that will allow them to repeat their success. With silicon reaching the physical limits of its capabilities sometime in the next decade, silicene could be exactly what the electronics industry needs. |
Gravity is pretty complicated if you think about it. The motion of a ball falling on the surface of the Earth is caused by the same interaction as the moon orbiting the Earth. That's crazy. It's even crazier to realize that humans figured out that these two motions (falling ball and moon) are from the same gravitational force. It sure doesn't look the same.
Now imagine that you are around during the time of Isaac Newton (let's say early 1700s). How do you make this model of universal gravity? I don't know how he did it, but Newton finally made the connection between the motion of planets (and moons) and the motion of objects on the surface of the Earth. He explains this connection with his famous thought experiment of a cannon firing a ball from a tall mountain. Here is his diagram from A Treatise of the System of the World.
The diagram shows that an object moving on the surface of the Earth could eventually become an object orbiting the Earth. He does this by imagining a cannonball—a super fast cannonball fired from a super high mountain. The actual range of this ball would be farther than a normal cannon ball because you would have take into the curvature of the Earth. Oh, right—you have to ignore air resistance. In fact, if you shoot the ball fast enough it will "miss" the Earth entirely and enter a low Earth orbit.
There you have it. Gravity on the surface of the Earth is the same as the gravity between the moon and Earth. Like I said, this is a big deal.
Analysis of the Image
I don't know who drew this diagram. Maybe it's been modified over time. However, I'm going to start with a version of it and then check it for accuracy. In particular, I want to know the height of the mountain and I want to check the trajectory of the cannon ball paths. It's just what I do.
Although it's just an image, it is still useful to video analysis software to analyze this image. Of course I'm going to use the free (and awesome) Tracker Video Analysis. From the image, I want to find the height of the "mountain". That's fairly straightforward. I can just set the radius of the Earth diagram to the radius of the Earth and then measure the height. This puts the top of the mountain at 1.198 times the radius of the Earth from the center of the Earth (it's easier to deal with this in terms of the Earth's radius). Oh, that makes the height of the mountain 19.8 percent the radius of the Earth—see how nice that is?
Just for comparison, Mount Everest has a height of 8848 meters. In terms of the Earth, this is 0.139 percent of the Earth's radius. Or to put this another way, Newton's mountain is seriously ginormous. I guess there are a bunch of other cool things we could consider regarding a mountain as high as Mt. Newton (that's what I'm calling it now)—but I will just leave those questions alone for now.
What about the trajectory of these cannonballs launched from Mt. Newton? Let's consider the trajectories of the first three cannonballs (the three lowest speeds). I don't know anything about the time for these motions, but I can get the x and y positions. Since this doesn't really fit with your normal projectile motion plots (y vs. x), I'm going to instead plot r vs. θ where r is the distance of the ball from the center of the Earth and θ is the angular position from the center of the Earth. Yes, this is polar coordinates.
Since the angle is measured from the horizontal x-axis, these cannonball trajectories start from the left and move right. I hope that's not too confusing. But the real question: are these trajectories real? I could show that an object interacting gravitationally with the Earth should have an elliptical trajectory, but I'm not going to do that. Nope. Instead I am going to make a numerical model and adjust the starting velocity until I get something close to one of these. It's going to be fun.
Here's the plan (it's the same plan as most numerical calculations). But here are the basic steps.
- Break the problem into very small steps of time (about 1 second in this case).
- Calculate the gravitational force vector on the cannon ball based on the position of the ball with respect to the Earth.
- Use this force to update the momentum of the ball.
- Use the momentum (and thus velocity) to update the position of the ball.
- Repeat until you want to stop.
That's it. Here's what you get. Yes, this is an actual and real numerical calculation. You can see the code by clicking the "pencil" icon. In the code view, you can change the starting velocity. If you don't change that velocity, you are only cheating yourself. Seriously. Try changing the velocity.
OK, that's starting to look like the Newton picture. But can I get a trajectory that is JUST like the picture? Let me adjust the starting velocity to see if I get data that is very similar to the above three shots (from the picture). Here's what I get (as a plot of radial distance vs. θ).
This is for the first three cannon shots and you can see the trajectories don't quite match up. With my best estimates, these are cannonball speeds of 2800 m/s, 4200 m/s, and 6200 m/s. Oh, just for fun the orbital velocity at the height of Mount Newton would be 7252 m/s. Go ahead and use that velocity in the code example above. It should make a nice orbit.
So, let me summarize what we have. The diagram of Newton's cannonball seems nice, but it's just a sketch. If only Newton had python.
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In 1632 Galileo argued for a Copernican view in his Dialogues of the Two Chief Systems of the World. The following year he was tried by the Catholic Inquisition for violating a 1616 Vatican edict forbidding such teachings. We will situate ourselves in 1633, consider the evidence for ourselves and decide (in a historical context) whether Galileo should be forced to abjure his beliefs. For our retrial, each person in class will represent someone supporting the Church or Galileo. After hearing the arguments, we will all act as the Inquisition and decide Galileo's fate.
- Did Galileo violate the 1616 edict of the Church? What guided the Church's interpretation of the heavens? Why did the Church view Galileo's ideas as dangerous--or wrong?
- How did Galileo argue for his views? How did Tycho Brahe interpret Galileo's evidence in a way that the Church found acceptable? How do we choose between alternative hypotheses?
- Was Galileo an unlucky victim of court politics? Did Galileo contribute to his own demise through personal attacks?
- The Vatican housed many great intellectuals of the time, including Cardinal Bellarmine. What did Bellarmine believe? How did he view Galileo's claims?
- Who was Giordano Bruno? How did his views influence the Church in this episode?
- If you had been Galileo, what claims would you have made publically? --in print? How would you have presented any claims regarded by others as controversial or heretical?
- How do members of your family or Church regard the Galileo affair? Given your historical knowledge, what might this reveal about our attitudes about science and religion?
The teacher will serve as the Grand Inquisitor, calling upon each team to present their case, posing additional questions, and allowing cross-examination by other teams. The whole class will serve as the Inquisition in deciding Galileo's fate.
Galileo Team #1
Prepare a case for the reasonableness of Galileo's arguments.
- Why did Galileo find a Ptolemaic view of the world unacceptable?
- Find and present three forms of evidence that Galileo used to support his claims. (You might refer both to The Starry Messenger of 1610 and the controversial Dialogues, central to the Inquisitions's trial.)
- Ideally, you should discuss why we should trust our observations, even though we know that they can be faulty and sometimes mislead us.
Galileo Team #2
Prepare an argument about how Galileo addressed common-sense objections to his claims.
- How did Galileo explain falling objects--why, if the earth moves, do objects that are dropped from a great height, fall directly underneath where they are dropped? (Research his ideas on circular inertia.)
- According to scripture, Joshua commanded the sun to stand still (indicating that it must move). How did Galileo reply? (Find his "Letter to the Grand Duchess Christina" in Stillman Drake's Discoveries and Opinions of Galileo or Finnochiaro's The Galileo Affair, and/or his letter to Piero Dini in John Burke's Science and Culture in the Western Tradition.)
- Ideally, consider the role of reasoning and observational evidence in reaching many of Galileo's conclusions.
Galileo Team #3
Prepare an argument that this trial is based primarily on inter-personal politics, not Church doctrine-- and that therefore Galileo should not now be held accountable to the 1616 edict.
- Read Biagioli's Galileo, Courtier, especially on the relationship between Galileo and Maffeo Barberini (later Pope Urban VIII) and on "the fall of the favorite."
- Discuss the professional challenges facing a "scientist," or natural philosopher, at this time. Why did Galileo become part of the Papal Court in Rome? What motivated Galileo? What motivated his critics?
Galileo Team #4
Prepare to question Cardinal Bellarmine.
- Read Bellarmine's letter to Paolo Foscarini of 12 April 1615 and other relevant documents (available in Finnochario's The Galileo Affair: A Documentary History or John Burke's Science and Culture in the Western Tradition).
- Ideally, research the views of the Jesuits, traditionally the intellectual branch of the Catholic Church. How did they support Galileo's position (esp. their views on sunspots and comets)?
- How do Bellarmine's intellectual views also help support Galileo's case?
Church Team #1
Prepare a case that Galileo's arguments against Ptolemaic views do not necessarily mean embracing Copernican views.
- For example, how did Tycho Brahe provide an important alternative for the Church?
- More specifically, how did the Church interpret Galileo's telescopic observations, such as the moons of Jupiter, the surface of the moon, and the phases of Venus?
Church Team #2
Prepare an argument that Galileo's claims contradict common sense and good ("scientific") observation. Summarize the role of "science" and of "regulating reason" in considering Galileo's conclusions.
- Find good reasons why we might not trust observations through a telescope.
- Suggest how a falling object should appear if the earth moved underneath it as it fell. (Ideally, you will calculate the proposed velocity of the earth in Rome, according to Galileo's views).
- Analyze the weaknesses in Galileo's arguments for tides.
- Ideally, summarize the arguments of Nicholas of Cusa about "regulating reason."
Church Team #3
Prepare an argument why Galileo's views--even if based on some apparent truths and fragments of evidence--are both misguided and dangerous for most Catholics.
- Describe how the earlier views of Giordano Bruno set an important precedent on Copernican views.
- Detail how Galileo's claims contradict excerpts from the Bible.
- Describe the importance of the 1616 edict, central to this trial. Ideally, explain why, if Galileo has been advocating Copernicanism since at least 1610, he should be held accountable now.
Church Team #4
Prepare to question Cardinal Bellarmine.
- Read Bellarmine's letter to Paolo Foscarini of 12 April 1615 (available in Finnochario's The Galileo Affair: A Documentary History or John Burke's Science and Culture in the Western Tradition).
- Compare his view to Nicole Oresme (1320-1382).
- Consult with Team #2 about Nicholas of Cusa's views about "regulation of reason."
- How do Bellarmine's intellectual views--both scientific and religious--help support a case to censure Galileo?
Prepare to answer questions from both Galileo's team and the Church.
- Read your letter to Paolo Foscarini of 12 April 1615 (available in Finnochario's The Galileo Affair: A Documentary History or John Burke's Science and Culture in the Western Tradition).
- Compare your view to that of Nicole Oresme (1320-1382).
- What interactions have you had with Galileo himself on his views? How has Galileo reacted to your arguments and sympathetic advice?
- Be prepared to reconcile your fundamental support of Galileo and the intellectual tradition he represents with your views about religion.
- to understand the complexity surrounding Galileo's trial in its historical context
- to research particular historical perspectives
- to write clearly
- to reflect on the relationship between science and religion
1/4 -- prepared written position statement based on your team's research
1/4 -- oral presentation at the retrial (clarity, completeness) (3-4 mins./person)
1/4 -- participation -- how effectively you pose questions, and also answer questions, making your position seem reasonable in the light of potential criticism
1/4 -- in-class essay justifying your position at the end of the retrial |
Historic cities that have been continuously inhabited through the current day, usually bear apparent evidence of their past in their urban grid. In large capital cities like Athens or Rome an observer can easily read the evolution of the city in discrete layers. The different historic realities coexist with the noisy modern everyday life.
Unlike this model, the modern face of Florence is entirely characterized by the late Medieval and Renaissance periods. The visitor is rarely aware that it existed on another historic time, and even less that it used to be an important strategic location, both during the roman and the byzantine eras. Instead, walking around the squares and the monumental buildings, one enjoys again and again the glory of the city under the rule of the Medici, during its greatest cultural and artistic flourish. Its Renaissance identity covers all other historic realities.
In fact, Florence, “Florentia” originally, was founded in 59 B.C, as an army camp of the Imperial Rome. The typology of the Roman camp distinguished by the two basic vertical axes is still visible in an aerial view of the city. The central Piazza della Republica was once their cross point, and the civic heart of the Roman city. Marks of this era can be discovered in all central squares of the city, but mostly underneath them, according to recent excavations.
In the Byzantine Era, Florence flourished as the head point for the communication between Rome and Po Valley and it was a disputable area between the Goths and the Byzantines. Traces of this period can be found more in the city’s architecture and art and less in its urban development. Characteristic artistic examples are the mosaics in the Battisterio and in the church of San Miniato Al Monte.
However, the remains of the pro-medieval eras are rather hard to be observed in the modern city. They are either integrated in the medieval grid, or altered in use and form so much that they are no longer recognizable – like the byzantine Torre della Pagliazza, originally, which serves as a restaurant today. For the attentive observer, the discovery of these traces can lead to a more profound understanding of the city’s urban development.
But why is the Renaissance spirit so intense in the city? It seems it is not only because of the artifacts and monuments that were created then, and still dominate its atmosphere. Moreover, the maximum exploitation of this era was a political decision that was taken in the time of the Medici, and continues to be valid up to today. The decision that Florence should be forever recognized as the city-symbol of the Renaissance, where culture, art, literature would lead the urban rhythms.
In what level do you think that the layers of the past should be apparent in the modern city?
Credits: Images by Marilena Mela. Data linked to sources. |
Perhaps the leading scientific question of the 17th and 18th centuries was how to find out exactly where you are when you are at sea. It had almost a mythical status and appeared in Gulliver's Travels as an example of an impossible problem. This difficult question not only stimulated a lot of mathematics, but also led, directly, to the modern world in which mathematics and machines work together.
The first breakthrough in navigation came when it was realised that the position of the Sun and the stars in the sky depend upon where you were on the (round) Earth. By seeing how the angle of the Sun changed the Greek mathematician Eratosthenes was able to calculate the radius of the Earth to surprising precision. Having worked out a coordinate system for the Earth (latitude and longitude) it was apparent that the latitude could be determined by measuring the angle of the noonday Sun above the horizon. Doing this required a good knowledge of angles and trigonometry. The angle itself could be measured using a sextant, again using ideas from trigonometry.
The Scilly naval disaster of 1707 was a direct result of sailors' inability to pin-point their longitude. 1550 men lost their lives as their ships struck rocks.
At that point the mathematics became much harder. In order to find the longitude it was necessary to determine the time at the location with reference to some absolute standard (for example, you would need to find out the local time with reference to the time in London). Mathematicians such as Newton struggled with this problem, and in a sense solved it: they found that the longitude could be determined from very accurate measurements of the location of the Moon, combined with a fearsome amount of calculation. Unfortunately, none of this was possible in the conditions at sea (and before the invention of the pocket calculator).
An accurate method of finding longitude had to wait until the development of a clock called H4 by John Harrison as a means of finding the time at Greenwich. See Dava Sobel's book Longitude for an excellent account of Harrison's struggles to build H4.
However, even with H4 a large amount of calculation was needed and here mathematics came into its own. In particular the development of spherical trigonometry, which was needed to solve the triangles on the surface of the Earth that were the results of the navigational measurements. Tables were constructed which solved triangles with a vast range of different angles. These were used in parallel with ephemerides, which were tables of the location of the Sun, planets and many stars for frequent time intervals in every day throughout the year. Looking at nautical tables from the 18th century I am overwhelmingly impressed by the amount of calculation needed to produce them, most of which would have been done by human computers.
The result of all of this mathematics, combined with the mechanical brilliance of Harrison, was completely transformative. It utterly transformed navigation by sea, making it much safer and cheaper to transport goods around the world. It revolutionised both the economy and also the process of exploration, leading to the modern world.There was a nice side product of all of this effort. The process of producing the navigational tables was essentially routine and open for being mechanised. Driven by this idea, in the 19th Century, Charles Babbage was inspired to design the difference engine, arguably the ancestor of all modern computers. Sadly, Babbage did not live to see his machines actually working (although a working model of the difference engine was built by the Science Museum in London), but his ideas have certainly led to the modern computer, and thus the modern world.
You can find out more in the following articles:
- Finding your place in the world explains the global coordinates of latitude and longitude,
- Latitude by the stars explains how latitude can be determined by measuring the angle of the Sun above the horizon,
- The longitude problem explains just that,
- Ada Lovelace: visions of today explores Babbage's attempt at building the first ever computer, and the contributions of his friend Ada Lovelace.
About this article
This article is adapted from one of Chris Budd's Gresham College lectures, part of a series called Mathematics and the making of the modern and future world. The lectures take place in London, are aimed at a general audience and free to attend.
Chris Budd OBE is Professor of Applied Mathematics at the University of Bath, Vice President of the Institute of Mathematics and its Applications, Chair of Mathematics for the Royal Institution, Gresham Professor of Geometry, and an honorary fellow of the British Science Association. He is particularly interested in applying mathematics to the real world and promoting the public understanding of mathematics. |
coronal mass ejection
A coronal mass ejection (CME) is a huge eruption of material from the Sun's corona into interplanetary space. CMEs are the most energetic of solar explosions and result in the ejection, over the course of several hours, of up to 100 billion kilograms of multi-million-degree plasma at speeds ranging from 10 to 2,000 km/s. They often look like bubbles and, when seen close to the Sun, can appear bigger than the Sun itself, though their density is extremely low.
In contrast to the steady-state solar wind, CMEs originate in regions where the magnetic field is closed and result from the catastrophic disruption of large-scale coronal magnetic structures, such as coronal streamers. CMEs can occur at any time during the solar cycle, but increase in daily frequency from about 0.5 during minimum years to about 2.5 around solar maximum. Fast CMEs – those which outpace the ambient solar wind – give rise to large geomagnetic storms when they encounter Earth's magnetosphere. Such storms, which can disrupt power grids, damage satellite systems, and threaten the safety of astronauts, can result from the passage either of the CME itself or of the shock created by the fast CME's interaction with the slower-moving solar wind. |
Since December 2013, the fear of the potential effects of this disease in the U.S. has grown significantly. Fear heightened when the first patient was diagnosed in our country on September 30th. While Ebola is a major international health concern, it does not represent even a fraction of the degree of risk that influenza does for us every year. In order to understand why, a closer look at how each disease spreads and some statistics are warranted.
- Ebola is a disease that requires direct contact with body fluids from someone who is infected with the virus or with objects contaminated with these fluids for person to person disease transmission. In contrast, flu can spread by respiratory droplets from infected individuals that can travel through the air up to six feet to potentially infect others. Additionally, the flu virus can live on surfaces outside the body for up to 48 hours and others can become infected when they touch these surfaces and then touch the eyes, nose, or throat without washing their hands first.
- Ebola is only contagious when infected people start displaying symptoms. Flu, on the other hand, can be spread to others a full 1-2 days before a person becomes ill from it.
In West Africa, there are key factors that have facilitated the transmission of Ebola:
- In this region of the world, the movement of human populations is approximately 7 times higher than the migration rates for other regions of the world (Alexander et al., 2014).
- Bushmeat is a primary dietary staple in many regions of West Africa, representing as much as ¾ of an area’s meat source. The consumption of bushmeat represents a primary way for humans to become infected with Ebola from infected animals.
- In this region, fear and mistrust of modern healthcare practices among a significant portion of the population remains, which can be very problematic for healthcare workers. In addition, these regions lack modern medical facilities and necessary medical supplies to offer humanitarian aid.
- One of the most significant findings that has helped foster the rapid spread of Ebola in these regions are the traditional burial practices that are utilized for the dead. When a loved one dies, it is customary in many of these regions for family members and friends to help wash and prepare the body for burial and they also may spend a long period of time with the deceased person’s body. With proper protective equipment lacking and the massive loss of body fluids that are typically lost when someone with Ebola dies, this factor represents a significant potential mode of disease transmission. In Guinea alone, it has been estimated that 60% of the Ebola cases seen have been linked to traditional burial practices, including one funeral alone that was linked to the spread of the Ebola virus and subsequent deaths of 365 other people (World Health Organization, 2014).
- The experience in the United States with the spread of the Ebola virus has been vastly different than the experiences in West Africa and can best be illustrated by looking at the cases of the first patient diagnosed with Ebola in the U.S. and the subsequent transmission to two nurses who cared for him. Both nurses who cared for the first patient did so at a time before there were clearly defined procedures for taking off equipment that healthcare workers use to help protect themselves from exposure, so it is thought that their exposures may have come from exposures to body fluid that may have occurred as part of the removal process. Furthermore, out of the 177 contacts of all three of these individuals with Ebola in Dallas (Chevalier et al., 2014) and the 164 Ohio contacts of the second nurse who traveled to this state (McCarty et al., 2014), not one person developed Ebola, even the persons living in the same household as the infected individual. While Ebola remains a significant concern today, the U.S. experience with the successful containment of the virus has been reassuring.
Unfortunately, the facts and statistics are not nearly as reassuring for influenza as can be seen from the following:
- Each year up to 20% of people living in the U.S. becomes ill from the flu (Centers for Disease Control and Prevention, 2014a).
- Approximately 200,000 people each year are hospitalized with flu cases and flu deaths have ranged from approximately 3,000 people all the way up to 49,000.
- In 2013, nearly 60% of the cases of flu in people that had to be hospitalized occurred in people ages 18 to 64 years old (Centers for Disease Control, 2014b).
- Flu related deaths have been seen in college students, such as the previously healthy 22 year old Wright State University student who died in 2013 (Ohio College, 2014) and the 29 year old mother of three in Texas who died earlier this year (James, 2014).
- College students are naturally very susceptible to getting sick from influenza in large part due to their hectic lifestyle and the exposures that they have to large numbers of others as a result of attending classes, social gatherings, and living arrangements
Fortunately, there is influenza vaccination available that can help protect college students and others against the flu and is widely regarded as the most effective way that individuals can protect themselves from becoming ill with the flu. Even in the years when it is not a perfect match for all of the strains that are circulating, such as what is occurring so far this year, it is still a good idea to get when this happens for three reasons:
- There are usually three or more influenza strains that circulate in any given year, so it will very likely be a good match for two of the three strains and will offer protection.
- There is also some evidence that suggests that previous exposure to flu strains in the past can offer up some protection if the same strain is encountered by the individual in the future
- Even when someone who has been vaccinated against the flu becomes ill from it during the same flu season, the severity of the illness tends to be milder than the cases seen in people who become ill who did not receive the flu vaccine during the season.
Another important fact to note is that many people do not realize that it takes two weeks for his/ her full immunity to build up after being vaccinated so he/ she may think that they got the flu from getting the vaccine when in actuality, they may have been exposed during to the virus during this two week period or to another disease that mimics flu symptoms.
In addition to getting the flu shot, there are other measures that people can take to help limit the spread of influenza, such as:
- Make sure that hands are clean before touching the eyes, nose, or throat
- Stay home when you are sick until you have been fever free for 24 hours without the use of ibuprofen, Tylenol, or other fever reducing substances.
- Avoid close contact (within 6 feet) with others who appear to be ill.
- Get in the habit of sneezing and coughing into your elbow, or cover them with a tissue
- Wash your hands with soap and water or alcohol gel or foam at key opportunities, including after touching objects and surfaces that are commonly touched by many others, such as elevator buttons, doorknobs, and stair banisters.
Alexander, K. et al., (2014). What factors might have led to the emergence of Ebola in West Africa? Retrieved from http://blogs.plos.org/speakingofmedicine/files/2014/11/Alexanderetal.pdf
Centers for Disease Control and Prevention (2014a). Seasonal influenza questions &answers. Retrieved from http://www.cdc.gov/flu/about/qa/disease.htm
Centers for Disease Control and Prevention (2014b), Flu activity during the 2013-2014 season. Retrieved from http://www.cdc.gov/flu/pastseasons/1314season.htm
Chevalier, M.S. et al., (2014). Ebola virus disease cluster in the United States- Dallas County, Texas, 2014. MMWR, 63(46), 1087-1088.
James, S. (2014). Healthy Texas mom dies of flu, 29, leaves 3 kids. Retrieved from http://abcnews.go.com/Health/healthy-texas-mom-dies-flu-29/story?id=21467701
McCarty, C.L. et al (2014). Response to importation of a case of Ebola virus disease- Ohio, October, 2014. MMWR, 63(46), 1089-1091.
Ohio college student dies from flu complications (2014), Retrieved from http://www.wlwt.com/health/Ohio-college-student-dies-from-flu-complications/18088622
World Health Organization (2014). Sierra Leone: a traditional healer and a funeral. Retrieved from www.who.int |
Density, Viscosity, and Buoyancy
Students investigate and identify properties of fluids including density, viscosity, and buoyancy. They Explain why some objects float in water and others do not. In addition, they determine the difference between density and viscosity.
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Designing an Autonomous Underwater Vehicle (AUV): Concepts in Lift, Drag, Thrust, Energy, Power, Mass, and Buoyancy
Engineer an autonomous underwater vehicle (AUV) to study concepts of physics. Using household materials, collaborative groups design and build an AUV and then test Newton's Laws of Motion as they apply them in underwater environments...
9th - 12th Science
Density Rainbow and the Great Viscosity Race
Students explore the densities and viscosities of fluids as they create a colorful 'rainbow' using household liquids. While letting the fluids in the rainbow settle, students conduct 'The Great Viscosity Race,' another short experiment...
6th - 9th Science |
A Bicameral system of government is one where there are two legislative or parliamentary chambers. The word comes from the Latin "bi" (meaning two) and "camera" (meaning chamber). In most cases they have different numbers of members. The smaller legislature is often called the "upper house" or "senate" and the larger is called the "lower house", and sometimes also called by another name such as "assembly" or "commons". For legislation to be passed, bicameral legislatures normally need a majority of members of both chambers to vote for the legislation.
Experts sometimes point out that often deadlocks occur in this kind of system. This can make it harder to pass laws. But others point out the checks and balances this system maintains. This prevents laws from being passed that favor a certain political faction, the government or group of people.
Bicameral systems in the world[change | change source]
- In the United Kingdom, the two chambers are called the House of Commons and the House of Lords.
- The United States Congress is bicameral.
- All the states apart from Nebraska use the bicameral system. Nebraska is unicameral.
- Australia has a bicameral system with a House of Representatives and a Senate. All the Australian states are also bicameral, except Queensland which is unicameral.
References[change | change source]
- "bicameral". The Free Dictionary/Farlex. http://www.thefreedictionary.com/bicameral. Retrieved 6 March 2016.
- "Your Guide to The Bicameral Legislature". Law.com. http://constitution.laws.com/bicameral-legislature. Retrieved 6 March 2016. |
To fight desertification, let’s manage our land better
Every year, we lose 24 billion tons of fertile soil to erosion and 12 million hectares of land to desertification and drought. This threatens the lives and livelihoods of 1.5 billion people now.
In the future,. Land degradation could also reduce global food production by up to 12% and push world food prices up by 30%. In Egypt, Ghana, Central African Republic, Pakistan, Tajikistan and Paraguay, land degradation could cause an annual GDP loss of up to 7%.
Pressure on land resources is expected to increase as populations grow, socio-economic development happens and the climate changes. A growing population will demand more food, which means that unsuitable or especially biodiverse land will be claimed for farming and be more vulnerable to degradation. Increased fertilizer and pesticide use related to agriculture will increase nutrient loading in soils, causing eutrophication and declines in fertility over time.—especially in drylands, which occupy 40% of global land area, and are inhabited by some 2 billion people. Urban areas, which are located in the world’s highly fertile areas, could grow to account for more than 5% of global land by mid-century.
Unless we manage our land better, every person will rely on just .11 hectares of land for their food; down from .45 hectares in 1960.
So how do we manage land better?
It will all come down to what we do with our soil, which is the most significant natural capital for ensuring food, water, and energy security while adapting and building resilience to climate change and shocks. The soil’s nutrient cycling provides the largest contribution (51%) of the total value (USD33 trillion) of all ‘ecosystem services’ provided each year. But soil’s important function is often forgotten as the missing link in our pursuit of sustainable development.
We must invest in applicable solutions that are transformative, and can be scaled up. Climate-smart agriculture is an alternative approach to managing land sustainably whilst increasing agricultural productivity. It includes land management options that sequester carbon and enhance resilience to climate change. Proven climate-smart practices such as agroforestry, integrated soil fertility management, conservation agriculture, and improved irrigation can ensure that land is used optimally, restored and managed in a manner that maximizes ecological, economic and social benefits.
Read the full article: World Bank |
Electron Beam Lithography (EBL) is a specialized technique for creating the extremely fine patterns required by the modern electronics industry for integrated circuits. This is possible due to the very small spot size of the electrons, whereas the resolution in optical lithography is limited by the wavelength of light used for exposure. The electron beam has wavelength so small that diffraction no longer defines the lithographic resolution.
How Does Electron Beam Lithography Work?
Derived from the early scanning electron microscopes, the technique in brief consists of scanning a beam of electrons across a surface covered with a resist film sensitive to electrons, thus depositing energy in the desired pattern on the resist film.
Processing Electron Beam Resists
Electron beam resists are the recording and transfer media for e-beam lithography. The usual resists are polymers dissolved in a liquid solvent. Liquid resist is dropped onto the substrate, which is then spun at 1000 to 6000 rpm to form a coating. After baking out the casting solvent, electron exposure modifies the resist.
Positive Tone and Negative Tone - the Two Forms of Electron Beam Resists
As in optical lithography, there are two types of e-beam resists: positive tone and negative tone, with the usual behaviour, i.e., positive resists develop away at exposed regions, whereas in the case of negative resist the developed region remains after development.
Using Polymethyl Methacrylate (PMMA) as Positive Electron Beam Resists
Polymethyl methacrylate (PMMA) is the standard positive e-beam resist, usually purchased in two high molecular weight forms (495K or 950K) in a casting solvent such as chlorobenzene or anisole. We make use of 950 PMMA, 4% in anisole. Electron beam exposure breaks the polymer into fragments (as shown in figure 1) that we dissolve in a 1:1 MIBK:IPA developer (MIBK is Methyl Isobutyl Ketone and IPA is Isopropyl Alcohol).
Figure 1. Electron beam exposure breaking the polymer into fragments.
The Component Parts that Make Up an Electron Beam Lithography System and the Elphy Quantum Product
The Materials and Microsystems Laboratory’s e-beam lithography system, called Elphy Quantum from Raith Gmbh, was delivered in April 2000. The Elphy Quantum is a universal lithography system which consists of a scan generator electronic (hardware) and a PC-based operating software. The system has the control in three major areas of Scanning Electron Microscopes (SEM): Beam Blanker control, Scan & Signal control and Stage control. Elphy Quantum is a Windows-based operating software and its functionality is based upon a modular design. Editing and pattern design is made simple with a GDSII internal editor. This allows users to build hierarchy patterns on different levels and designs with any dose level. Then pattern data can be generated with the simple CAD program included, or can be imported from a DXF (Auto CAD) file.
Industry Applications for Electron Beam Lithography
Application areas of e-beam lithography span a wide range from cryo-electric devices, opto-electronic devices, quantum structures, transport mechanism studies of semiconductor/superconductor interfaces, microsystem techniques, optical devices.
Using Silicon-Based Structures for Photonic Applications
Currently, our interest is principally focused in direct applications for the realization of silicon-based structures for photonic applications. Photonic crystals can be created in semiconductors using standard nanofabrication technology (electron beam lithography and dry-etching), and they are interesting to realize optoelectronic structures. |
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