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Seymouriamorpha were a small but widespread group of limbed vertebrates (tetrapods). They have long been considered reptiliomorphs, and most paleontologists may still accept this point of view, but some analyses suggest that seymouriamorphs are stem-tetrapods (not more closely relates to Amniota than to Lissamphibia). ... | <urn:uuid:07bc2709-590c-4dba-ad11-cc7bfc43815f> | 3.71875 | 660 | Knowledge Article | Science & Tech. | 57.26456 |
Using the interactivity, can you make a regular hexagon from yellow
triangles the same size as a regular hexagon made from green
If the yellow equilateral triangle is taken as the unit for area,
what size is the hole ?
Which of these roads will satisfy a Munchkin builder?
Which of these triangular jigsaws are impossibl... | <urn:uuid:3084e913-38d0-49f7-9d4d-06c00cbf2b5a> | 2.734375 | 163 | Content Listing | Science & Tech. | 50.520179 |
|+ Visit the NASA portal|
The rover we designed for transportation of our Mars’ astronauts would be able to hold four astronauts. It has tread wheels two on either side of a ball shaped rover giving it stability. The wheel treads would have the ability to raise and lower to accommodate changes in the Martian landscape,... | <urn:uuid:8735e886-37e3-4fc1-aa5b-fe02dce19c44> | 3.796875 | 248 | Knowledge Article | Science & Tech. | 47.390098 |
Science Fair Project Encyclopedia
Big dumb booster
Big Dumb Boosters (BDB) are a general class of launch vehicle built around the idea that it is cheaper to build and operate a large, strong, heavy rocket of simple design than it is to build a smaller, lighter, more cleverly-designed one. Even though the large booster ... | <urn:uuid:8c2d1430-b5cb-482e-921f-355c7cec3c80> | 3.609375 | 207 | Knowledge Article | Science & Tech. | 48.213047 |
The black-footed ferret (Mustela nigripes) once occurred throughout the grasslands and basins of interior North America, from southern Canada to Texas . Black-footed ferrets live in burrows made by prairie dogs, hunt prairie dogs for food and are obligate associates of the prairie dog . Their historical range is nearly... | <urn:uuid:ef97af06-ea62-4c94-8758-8f9c0f636efa> | 3.703125 | 3,198 | Knowledge Article | Science & Tech. | 56.82413 |
Carbon dioxide (CO2): Carbon dioxide occurs naturally in the atmosphere, is exhaled by humans and other animals and is used by plants in photosynthesis. Growing plants and the oceans act as carbon sinks, taking carbon dioxide from the atmosphere and storing the carbon. As plant material decomposes, the carbon is releas... | <urn:uuid:9bc81c90-5dff-47f6-8169-13c49ced5400> | 3.796875 | 800 | Structured Data | Science & Tech. | 23.818364 |
A tornado is a violently rotating column of air in contact with and extending between a cloud (often a thunderstorm cloud) and the surface of the earth. Winds in most tornadoes blow at 100 mph or less, but in the most violent, and least frequent, wind speeds can exceed 250 mph.
Tornadoes, often nicknamed "twisters," ty... | <urn:uuid:d186afb7-da99-4b57-92ab-2d08af0c6061> | 4.21875 | 366 | Knowledge Article | Science & Tech. | 39.99338 |
While the work of Mausumi Dikpati suggests that meridional flows in the sun's convective layer may allow us to forecast sunspot activity (6 March, p 38), other forces may also be at work. In particular, the giant planets in the solar system may play a role through the gravitational pull they exert on the massive amount... | <urn:uuid:20122795-0890-44e8-a395-a344506a39b7> | 3.296875 | 216 | Truncated | Science & Tech. | 48.704907 |
Marine Invasive Species
Brenda Bowling, Dickinson Marine Lab, Dickinson,Texas
Approximately 50,000 non-indigenous species have been introduced into the United States, especially in the last 200 years. In fact, nearly 98% of the crops and animals raised for food in our agricultural industry were introduced from other co... | <urn:uuid:bedb4440-238a-4118-b063-62b09e876106> | 3.796875 | 1,314 | Knowledge Article | Science & Tech. | 25.903494 |
A photo of the COSPIN instrument
Click on image for full size
European Space Agency
COSPIN Instrument Page
COSPIN is one of the instruments on the Ulysses spacecraft.
COSPIN stands for the COsmic and Solar Particle INvestigation. The COSPIN instrument is actually made up of 5 different sensors: the Dual Anisotropy Tele... | <urn:uuid:12a7fdf4-8083-4763-83c0-fff8b7c72787> | 3.4375 | 748 | Knowledge Article | Science & Tech. | 55.958203 |
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.
2002 January 7
Explanation: Sometimes the simplest shapes are the hardest to explain. For example, the origin of the mysterious cone-shaped region s... | <urn:uuid:eb096c06-7396-40dc-b252-03798a0323d1> | 3.9375 | 240 | Knowledge Article | Science & Tech. | 43.265955 |
This book will be on earthquakes, a natural disaster that can kill and destroy. But with proper prediction, we can figure out where there is a lot of danger and how to prevent as many casualties as possible. If you are interested in volcanoes, but think that you should learn about seismology as well, then here is the p... | <urn:uuid:f8e69e36-2737-4f90-9730-848bf480c7dd> | 3.859375 | 233 | Content Listing | Science & Tech. | 31.707895 |
Evolutionary and Historical Ecology
To understand the conditions under which the ponderosa pine forests of the American Southwest evolved, a functional, evolutionary theory of ecosystem health is essential. Without it, we are unlikely to be able to provide prescriptions for the return of our forests to health, much les... | <urn:uuid:aefeac5e-a2aa-4595-bc8f-9f3fd5a015e9> | 3.1875 | 1,153 | Knowledge Article | Science & Tech. | 37.603474 |
I was a bit surprised to read the attached article in the IET Power Engineer, because I have been a member of the UK Institute of Electrical Engineers for many years and this kind of very technical nuclear article was usually in the UK BNES journal. Maybe nuclear is getting more relevant. The article is about improving... | <urn:uuid:c67cbb89-d6f7-40eb-b36a-be09e89e47a6> | 3.0625 | 242 | Comment Section | Science & Tech. | 38.767444 |
Save the environment... and moneyNPR reports on another significant, if underreported source of pollution: computers.
Computers and computer monitors in the United States are responsible for the unnecessary production of millions of tons of greenhouse gases every year, according to the Environmental Protection Agency. ... | <urn:uuid:c3d671fc-9c4a-4b12-ae24-b008e40d8dcd> | 2.71875 | 153 | Personal Blog | Science & Tech. | 33.296891 |
One Hundred and Fifty Years of Debris-Flows in the Swiss Alps
Bollschweiler, M. and Stoffel, M. 2010. Changes and trends in debris-flow frequency since AD 1850: Results from the Swiss Alps. The Holocene 20: 907-916.
In a study designed to explore this question, Bollschweiler and Stoffel developed a history of debris-fl... | <urn:uuid:e929388b-7e9a-4169-9578-03971ba4068e> | 3.25 | 522 | Academic Writing | Science & Tech. | 51.193875 |
Read all about the number pi and the mathematicians who have tried to find out its value as accurately as possible.
Use the Cuisenaire rods environment to investigate ratio. Can you
find pairs of rods in the ratio 3:2? How about 9:6?
A card pairing game involving knowledge of simple ratio.
Rachel has a bag of nuts.
For... | <urn:uuid:20574fce-20d2-4668-b55b-4b0a88f9d594> | 2.84375 | 106 | Content Listing | Science & Tech. | 68.026252 |
Red-Eyed Tree Frog (Agalychnis callidryas)
Thanks to their big bulging red eyes, it's not hard to recognize red-eyed tree frogs! This alien-like feature is a defense mechanism called "startle coloration." When the frog closes its eyes, its green eyelids help it to blend in with the leafy environment. If the nocturnal f... | <urn:uuid:c926620f-8715-4a4f-a8b2-d483eff3fd4e> | 4.03125 | 555 | Knowledge Article | Science & Tech. | 49.431952 |
The central regions of our Galaxy are dominated by the crowded stellar bulge. Although stars in the bulge are typically observed to be almost as abundant in metals as the sun, the bulge is generally considered to have been one of the earliest parts of the Galaxy to form.
This project is on microlensed stars in the Gala... | <urn:uuid:03268a48-2acd-4a8d-82dd-35a1cd56f169> | 3.65625 | 294 | Academic Writing | Science & Tech. | 45.585237 |
This X-Ray movie of the sun, produced by Dr. Steven Hill of NOAAs Space Environment Center, is from October 19, 2001 through November 4, 2001. The data for it is from GOES Solar X-Ray Imager, SXI, which is an instrument attached to the GOES 12 satellite. The Space Environment Center receives a stream of the data which ... | <urn:uuid:8bdb4735-f93d-40e3-962e-c1338a2e9a4f> | 3.671875 | 338 | Knowledge Article | Science & Tech. | 44.967672 |
Science Fair Project Encyclopedia
The stamen is the male organ of a flower. Each stamen generally bears four pollen-sacs (microsporangia) which are associated to form the anther, and carried on a stalk called the filament. The development of the microsporangia and the contained haploid spores (called pollen-grains) is ... | <urn:uuid:587760ae-bd7d-4208-89b3-8bc8d257723c> | 3.859375 | 800 | Knowledge Article | Science & Tech. | 35.617941 |
Camelopardalis and Ursa Minor - Downloadable article
In the Giraffe and Little Bear, galaxies, nebulae, star clusters, and other stellar arrangements dance around the North Celestial Pole.
March 3, 2009
|This downloadable article is from an Astronomy magazine 45-article series called "Celestial Portraits." The collecti... | <urn:uuid:0fe5831f-7e8e-4c0f-a61f-4d46d13fbdf3> | 3.03125 | 465 | Truncated | Science & Tech. | 45.736007 |
We've shared with you the story of rafting ants, but there's so much more to these little insects. We thought we would take recent ant stories and share them with you on this Friday news round-up.
Ants Defending Trees
Did you know that some ants defend their tree homes from invading plants? But how can they tell the di... | <urn:uuid:4c5c7e06-e9c0-4706-9de6-8709639b8606> | 3.453125 | 803 | Content Listing | Science & Tech. | 43.31362 |
Let denote a constant interval number system, built from an underlying number system :
A general methodology for constructing constant interval models of real functions will be presented in this section. We will assume that an order-preserving mapping exists:
Throughout this section we may treat members of as constant ... | <urn:uuid:4e24b5af-923c-45ea-a9c8-68cc3c22d78a> | 2.984375 | 209 | Academic Writing | Science & Tech. | 23.682267 |
TLS is a Win32 mechanism that allows multiple threads of a process to store and retrieve data that is unique for each thread. Any one thread allocates an index, and then this index is available for use by all the threads in the process. Each thread in the process has its own TLS slot for this index where a 32-bit point... | <urn:uuid:eb62f10c-9498-4443-bb08-ea43130fe99c> | 3.125 | 317 | Documentation | Software Dev. | 48.938868 |
Bored Wombat wrote:
small technical point; Isn't it winter in the Antarctic now? and don't we know why antarctic sea ice is expanding in the summer anyway?http://news.nationalgeographic.com/news ... vironment/
Some people try and argue that it's the Ozone Hole that has created circulation changes that have managed to c... | <urn:uuid:6a403074-b828-47d5-a994-5726a46775e8> | 2.6875 | 500 | Comment Section | Science & Tech. | 44.286014 |
The wars and rebellions that punctuated China's ancient dynasties have inspired epic books and films. Now it seems the course of the nation's history may have been influenced by a rather more mundane force: the weather.
China's archives track the lives of the country's clans over the last millennium in voluminous detai... | <urn:uuid:5d1497a9-13f9-462f-9bfe-c5ad483cdf69> | 3.046875 | 213 | Truncated | Science & Tech. | 54.209258 |
Caitlin Stier, video intern
Stare at the ellipses in this video and you'll start to experience trippy effects. The illusion, developed by vision researchers Gideon Caplovitz and Kyle Killebrew of the University of Nevada in Reno, features curved shapes spinning at a constant rate where changes in contrast, width and co... | <urn:uuid:1a7d6270-218d-48b8-aad5-39a9687b8e67> | 3.375 | 406 | Personal Blog | Science & Tech. | 42.970433 |
Earth Science Literacy - Big Idea 3
Earth is a complex system of interacting rock, water, air, and life.
Big Idea 3.1
The four major systems of Earth are the geosphere, hydrosphere, atmosphere, and biosphere. The geosphere includes a metallic core, solid and molten rock, soil, and sediments. The atmosphere is the envel... | <urn:uuid:48bbf87d-9e97-4d1b-8d4b-02c598ed41f5> | 3.921875 | 689 | Tutorial | Science & Tech. | 43.589 |
Hamiltonian Circuits in Plane Graphs
Department of Mathematics
York College (CUNY)
Jamaica, New York 11451
Attempts to prove the Four Color Conjecture (now the Four Color Theorem), which asked if every plane graph could be face colored with 4 or few colors, resulted in considerable interest in whether or not plane 3-va... | <urn:uuid:71f63e8d-318f-4b25-bdf2-909eaae999f2> | 3.015625 | 1,381 | Academic Writing | Science & Tech. | 55.139792 |
Yes, there are cases where one gene has become two. Or, at least, where multiple functions carried out by a single protein, the product of one gene, are carried out by distinct proteins, the products of different genes, in another species.
One case I have personally worked with is the bacterial SelB protein. It is esse... | <urn:uuid:495b0143-8e8a-47df-b579-b1c003826298> | 2.9375 | 348 | Q&A Forum | Science & Tech. | 47.72639 |
Project: BOREASProject: BOREAS
The Boreal Ecosystem-Atmosphere Study was a large-scale international interdisciplinary experiment in the boreal forests of central Canada. Its focus was improving our understanding of the exchanges of radiative energy, sensible heat, water, CO2 and trace gases between the boreal forest a... | <urn:uuid:656367f3-a116-44c1-8f5d-c8800e914f90> | 3.265625 | 379 | Structured Data | Science & Tech. | 47.51854 |
One way RNA-based life might have survived could have been to retreat to niches where DNA-based life could not compete. RNA-based organisms might not make proteins, and so they could live where key ingredients for proteins, like sulfur, are absent. RNA-based organisms might also be far smaller than DNA-based life, allo... | <urn:uuid:b990b9aa-461b-498b-8138-dcd134c8c8d8> | 4.375 | 1,686 | Nonfiction Writing | Science & Tech. | 47.987713 |
FREE ENERGY, SIMPLY EXPLAINED
Imagine a cylinder, closed at one end and fitted with a sliding piston at the other. Trapped between the piston and the blind end is an ideal gas. (Visualized as a lot of particles flying around like ricocheting rifle bullets, with random energies - loosely speaking, speeds - and random po... | <urn:uuid:92cc12a9-f42c-46ea-a78c-b34f4f78088d> | 3.609375 | 675 | Personal Blog | Science & Tech. | 47.845151 |
Figure 4.1 Hoefer SE 400 Sturdier Electrophoresis units
Electrophoresis may be the main technique for molecular separation in today's cell biology laboratory. Because it is such a powerful technique, and yet reasonably easy and inexpensive, it has become commonplace. In spite of the many physical arrangments for the ap... | <urn:uuid:c4aed503-29ab-4fb7-aa33-7749a9e9dffb> | 3.109375 | 2,146 | Academic Writing | Science & Tech. | 37.982705 |
Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts. It differs from particle physics in that it spans a lower energy range where nucleons and even nuclei are stable and interactions can generally be described in terms of nucleon and meson degrees of fr... | <urn:uuid:8549f392-afaa-4a7a-977e-a2b3a5b2dc0a> | 2.953125 | 160 | Knowledge Article | Science & Tech. | 25.220093 |
Going Supernova 3Dgif
Click on Refresh Page
to activate gif movie
Modeling the collapse of a massive star represents one of the greatest challenges in computational physics. All four fundamental forces of nature are in play, giving us a cosmic laboratory with conditions unlike anywhere else in the Universe. Only if we ... | <urn:uuid:d7ab8a0e-563a-4d8c-ba50-0db9c6512257> | 3.640625 | 933 | Personal Blog | Science & Tech. | 27.363036 |
By Jay Kernis
Scientists from around the world are building the world’s most advanced radio telescope in Chile’s Atacama Desert, on a plateau half-way between Earth and space above 40 percent of the planet’s atmosphere.
The observatory, referred to by the acronym ALMA, officially known as the Atacama Large Millimeter/S... | <urn:uuid:2281dbf8-b5fe-4a30-8b11-e552760b3d2d> | 3.140625 | 655 | Audio Transcript | Science & Tech. | 49.990767 |
This week, on WNYU’s science and technology show The Doppler Effect, we had a really interesting sound.
That is the sound of the radio frequencies of the aurora borealis.
Now, let’s be clear. That’s not a sound you can hear. If you listen to the whole segment from the WNYU show (here) you’ll hear Bez Laderman and Jonat... | <urn:uuid:e02a2027-f08c-431b-87e8-387061522a48> | 3.15625 | 494 | Personal Blog | Science & Tech. | 66.711667 |
There are four types of biological transmission , they are :
A- PROPOGATIVE TRANSMISSION - in this type of transmission only multiplication of the organism takes place in the host without any kind of development that is change in form . example for this type of transmission is THE PLAGUE BACILLUS IN THE RAT FLEA.
B -CY... | <urn:uuid:e6ce5335-fa5b-4b12-9322-c72ec3816066> | 2.796875 | 228 | Listicle | Science & Tech. | 24.234231 |
Infrared Satellite Images
Infrared satellite measurements are related to the brightness temperature.
For an infrared picture, warmer objects appear darker than
colder objects, as in the example below
(a composite of data from
GOES-8 and GOES-10 satellites).
Since temperature in the troposphere decreases with height,
hi... | <urn:uuid:1862d7f8-ee61-4f21-9d70-5a045fb88624> | 3.671875 | 159 | Knowledge Article | Science & Tech. | 41.639231 |
Simply begin typing or use the editing tools above to add to this article.
Once you are finished and click submit, your modifications will be sent to our editors for review.
testing for geostress
...in choice of chamber orientation, shape, and support design, is usually determined in exploratory drifts. Two methods are... | <urn:uuid:f8631f62-6201-40b1-a7ce-748dc3a93aa5> | 2.875 | 146 | Truncated | Science & Tech. | 51.726212 |
DORMOUSEDORMOUSE (MUSCARDINUS AVELLANARIUS)
LOCAL BIODIVERSITY ACTION PLAN
Dormice usually weigh between 15-30g, reaching 65-85mm in length. They have a white throat, pale yellow/white fur on their underparts and brown/orange fur on their upperparts. Their thick bushy tail makes them easy to distinguish from other mous... | <urn:uuid:b234feee-a564-4f07-94fc-43852829f878> | 3.625 | 1,340 | Knowledge Article | Science & Tech. | 48.880388 |
When writing up HTML source code, all line breaks created by pressing the 'Enter' key will be ignored by the web browser and will not register as line breaks on the actual web page. In order to create line breaks and hence format your visible text into paragraphs, you will use what are known as block-level
or block ele... | <urn:uuid:49481e3d-aae8-4f0b-8cbe-3ee317351583> | 4.15625 | 1,043 | Tutorial | Software Dev. | 61.592068 |
THE NEEM, a tropical tree grown in north Queensland, could become the basis of an important new pesticide industry. Compounds extracted from the seeds of the neem could replace many of the synthetic organic pesticides now in use.
More than 300 of the world's worst insect pests can be controlled by neem seed extracts, w... | <urn:uuid:a70f751a-3272-4397-bb82-066f82c139e0> | 3.234375 | 211 | Truncated | Science & Tech. | 44.444934 |
Waves, Sound and Light: Wave Basics
Wave Basics: Audio Guided Solution
Sachi is rock'n to her favorite radio station - 102.3 FM. The station broadcasts radio signals with a frequency of 1.023 x 108 Hz. The radio wave signal travel through the air at a speed of 2.997 x 108 m/s. Determine the wavelength of these radio wa... | <urn:uuid:2375dffd-6aac-4edf-ae19-29d35c4fc255> | 4.3125 | 276 | Tutorial | Science & Tech. | 61.394156 |
Heptachlor was used extensively until the 1970s as a broadspectrum insecticide on a wide variety of agricultural crops, with the major use on corn. It also had nonagricultural uses including seed treatment, home and garden uses, and termite control.
It has a low vapour pressure, low water solubility and is hydrolysed i... | <urn:uuid:21f54b45-1c2b-4945-b34f-1da45e0a292b> | 3.296875 | 452 | Knowledge Article | Science & Tech. | 34.492743 |
The intricate cosmic web of dark matter and galaxies spanning more than one billion light years. The pink-yellow plumes seen with gravitational lensing show us where the dark matter is.
What is Gravitational Lensing?
Cosmology is the branch of astronomy which asks the biggest questions of all – what is the Universe mad... | <urn:uuid:344ba3e7-cee6-4b1a-9c42-64834335863f> | 4 | 2,719 | Knowledge Article | Science & Tech. | 46.809957 |
What Are They, and Where Are They?What Are They, and Where Are They?
SUMMARY: The jovian planets are essentially big balls of gas, each surrounded by many moons and rings.
Moons and Rings
Why so different?
Jupiter's Relative Size
The Great Red Spot Pinwheel
Can Photosynthesis Occur at Saturn?
Patterns and Fingerprints
... | <urn:uuid:da105e25-1704-40f4-9b46-c35596216e85> | 4.28125 | 1,038 | Knowledge Article | Science & Tech. | 40.107511 |
In summary, the resent observational results in cosmology strongly suggest that we live in a universe that is spatially flat, expanding at an accelerated rate, homogeneous and isotropic on large scales, and is approximately 13 billion years old. The expansion of the universe is described by Eq. (63), and its metric by ... | <urn:uuid:adca7275-9b55-40de-9ea2-2b1656420317> | 3.046875 | 488 | Academic Writing | Science & Tech. | 32.072057 |
- This is about distribution in a mathematical sense, other meanings can be found at distribution
In mathematics, a distribution is a generalisation of a function. Distributions were introduced in the middle of the 20th century by Laurent Schwartz, who received a Fields Medal for his work on them. The Fields medal is c... | <urn:uuid:c18be62c-d1f6-434e-b627-e092e84272c8> | 3.671875 | 216 | Knowledge Article | Science & Tech. | 34.301708 |
Measure Chlorophyll in Field?
sl5dl at cc.usu.edu
Mon Jun 12 14:57:11 EST 1995
bo1000 at aol.com (Bo1000) wrote:
>Does anyone know how to measure chlorophyll-a in lake water? We would
>prefer a small device we could carry in a boat in order to understand the
>photosynthetic activity of algae, etc.
We measure foliar chl... | <urn:uuid:a624953b-6b73-4f6f-bdb9-2d92c58ca7a8> | 2.828125 | 194 | Comment Section | Science & Tech. | 51.860702 |
Spectrum to RGB Conversion
|In 1931, the International Commission on Illumination (CIE)
defined three standard primaries, called X, Y
and Z. The corresponding functions , , and are called color-matching
functions. The color-matching function is defined to match the eye's
sensitivity to brightness; the other two do not ... | <urn:uuid:28e12795-bc1d-4bf0-a9b7-fde54add8653> | 3.8125 | 242 | Knowledge Article | Science & Tech. | 65.031626 |
clone, group of organisms, all of which are descended from a single individual through asexual reproduction, as in a pure cell culture of bacteria. Except for changes in the hereditary material that come about by mutation, all members of a clone are genetically identical. In 1962 John Gurdon was the first to clone an a... | <urn:uuid:c4784d27-07bb-4dbf-8123-4b35ff861ac6> | 3.5625 | 461 | Structured Data | Science & Tech. | 29.500766 |
The Gulf oil spill, terrible though it is, has focused attention on one of the least-known environments on earth. Scientists used to believe that the deep ocean was uninhabited. As scientist Tim Flannery explains, “The eternal dark, the almost inconceivable pressure, and the extreme cold that exist below one thousand m... | <urn:uuid:85b1daf7-8be7-4925-8aa2-365392d6c8f1> | 3.671875 | 746 | Content Listing | Science & Tech. | 44.638216 |
The orange K type star is towards the dimmer and cooler end of the sequence of spectral types, although still hot and bright enough for any planets to be good candidates for colonization. These stars are distinguished by a strong metallic line, and molecular bands of CH and CN.
These stars are somewhat like Sol, althou... | <urn:uuid:ca8f76df-2710-42cc-ae7b-a5b15e9f56c0> | 3.15625 | 291 | Knowledge Article | Science & Tech. | 49.446266 |
An interesting prime number spiral was discovered in 1963 by Stanislaw M. Ulam, and is now called "the Ulam spiral". It reveals a strange property of the prime numbers.
A positive integer (1, 2, 3, ... ) greater than 1 is called prime if its only divisors are 1 and itself. The first few prime numbers are 2, 3, 5, 7, 11... | <urn:uuid:10eb8ca8-2fa5-4694-babe-9fac3cf377f8> | 3.703125 | 307 | Knowledge Article | Science & Tech. | 67.137323 |
We recently asked National Weather Service forecaster Alex Tardy to explain why San Diego, Riverside and San Bernardino counties have had so many thunderstorms in recent weeks. (Turns out it is a seasonal thing, mostly.) We chatted Tardy up again when we became curious about the life cycle of a thunderstorm. Here's som... | <urn:uuid:6ab52497-f273-4726-b0ef-876bb34530a7> | 3.515625 | 432 | Q&A Forum | Science & Tech. | 61.621784 |
Can You See Orion?
The interactive animation below shows you what the constellation Orion might look like.
You can adjust the darkness of the sky by moving the top slider back and forth. Move it to the right (towards the tent) to see Orion in a dark sky, the way it might look if you were out camping far away from any l... | <urn:uuid:9268b657-87c0-462e-bf3d-7fce30993b48> | 3.4375 | 630 | Content Listing | Science & Tech. | 58.733744 |
AstronomyAstronomy, which etymologically means "law of the stars", (from Greek: αστρονομία = άστρον + νόμος) is a science involving the observation and explanation of events occurring outside Earth and its atmosphere. It studies the origins, evolution, physical and chemical properties of objects that can be observed in... | <urn:uuid:39e8c1d3-e73a-4de1-be32-a6841bb182f6> | 3.65625 | 3,185 | Knowledge Article | Science & Tech. | 27.184357 |
Karol Borsuk conjectured in 1933 that every bounded set in can be covered by sets of smaller diameter. Jeff Kahn and I found a counterexample in 1993. It is based on the Frankl-Wilson theorem.
Let be the set of vectors of length . Suppose that and is a prime, as the conditions of Frankl-Wilson theorem require. Let . Al... | <urn:uuid:5b5c5465-fb32-4b2d-b399-2939c0caec0f> | 2.6875 | 400 | Personal Blog | Science & Tech. | 60.671828 |
Eqs. (61) and (62) provide maximum likelihood estimators only when the noise in which the signal is buried is Gaussian. There are general theorems in statistics indicating that the Gaussian noise is ubiquitous. One is the central limit theorem, which states that the mean of any set of variables with any distribution ha... | <urn:uuid:901d87c5-259e-410b-a239-50321d8e73ff> | 3.40625 | 1,348 | Academic Writing | Science & Tech. | 35.875117 |
Ecology is the study of the interaction of living things with their environment.
Investigating ecosystems is difficult because of the huge number of biotic and abiotic factors. An area is studied by quadrat or transect sampling. Statistics like standard deviation and Chi Squared are used to analyse. See Studying Ecosys... | <urn:uuid:68f3d507-0449-44c4-a567-aa3900457804> | 3.625 | 454 | Knowledge Article | Science & Tech. | 28.995158 |
Alaska creatures without us
By Ned Rozell In Alan Weisman¹s book, The World Without Us, the author ponders ³a world from which we all suddenly vanished. Tomorrow.² In last week¹s column, a few experts discussed the fate of Alaska structures if Alaskans were to disappear. This week, people who study Alaska¹s wildlife do... | <urn:uuid:a7feecb6-0846-4294-9fdd-8e541a37372c> | 3.609375 | 1,157 | Truncated | Science & Tech. | 41.390447 |
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(video available at Science and Technology News Network)
In the search for suitable dwelling places within our own solar system, requirement number one is liquid water. If the Earth were too ... | <urn:uuid:81ed74ab-13af-422a-aebd-6cd5908904c8> | 3.671875 | 732 | Truncated | Science & Tech. | 43.140444 |
has a first page and every catalog a first entry.
And so this lovely blue cosmic cloud begins the
den Bergh Catalog (vdB) of stars surrounded by reflection nebulae.
Interstellar dust clouds
reflecting the light of the nearby stars,
the nebulae usually appear blue because scattering by the dust grains
is more effective ... | <urn:uuid:e3efccb5-5f24-474c-8e65-a2514470e970> | 2.8125 | 215 | Knowledge Article | Science & Tech. | 44.987047 |
|If you drop a hammer and a feather together, which reaches the ground first?
On the Earth, it's the hammer, but is the reason only because of
Scientists even before
and tested this simple experiment and felt that without air resistance, all objects would fall the same way.
Galileo tested this principle himself and not... | <urn:uuid:f7417f09-03cf-49bf-8d67-83786041ff10> | 3.96875 | 245 | Knowledge Article | Science & Tech. | 36.072984 |
Full name: Faraday constant
Plural form: faradays
Category type: electric charge
Scale factor: 96485.3399
The SI derived unit for electric charge is the coulomb.
1 coulomb is equal to 1.03642688209E-5 Faraday constant.
Valid units must be of the electric charge type.
You can use this form to select from known units:
I'... | <urn:uuid:0b88e418-f6fc-4b06-9408-67449b6631d4> | 2.96875 | 168 | Structured Data | Science & Tech. | 45.207522 |
radical, in mathematics, symbol placed over a number or expression, called the radicand, to indicate a root of the radicand. When used without a sign or index number, it designates the positive square root of the radicand, i.e., 2. If both square roots are meant, the radical sign is preceded by ±. To indicate higher ro... | <urn:uuid:ef4384bc-a50f-480b-a51e-5c413971862c> | 3.96875 | 179 | Knowledge Article | Science & Tech. | 42.516935 |
InformATE (Inform Ahora Totalmente en Español -- Inform, Now Totally in Spanish) is a programming language and a design system for interactive fiction in the Spanish language. InformATE is an Inform library, based on Inform v6.30. It was originally created by José Luis Díaz as "Zak McKraken", and is currently mantained... | <urn:uuid:1f3c78d1-3b69-41ef-8d33-45815b2f2e9a> | 2.75 | 486 | Knowledge Article | Software Dev. | 36.377639 |
Pollution of subsurface waters and soils is a common problem across the United States and the world. However, a growing body of evidence suggests that laboratory studies, particularly those involving biological and chemical remediation, do not accurately mimic what occurs in the field. These laboratory studies usually ... | <urn:uuid:67f6f5a4-8f93-47fe-a52d-5991ade8b166> | 3.125 | 713 | Academic Writing | Science & Tech. | 28.915148 |
If a 1.5V battery stores 5.0kj of energy,for how many minutes could it sustain a current of 1,2A?
I got around 5.48g... I think it's wrong
When I use this formula do I have to convert torr to atm and mL to L?
If there are 5 liters of oxygen gas (O2) at 300 K and 400 torr, what will it weigh? Answer in units of g. Do I ... | <urn:uuid:7136614d-0a6a-40e1-8e4a-ddefd7d87fcc> | 2.796875 | 222 | Q&A Forum | Science & Tech. | 94.533579 |
This module provides an interface to the mechanisms used to implement the import statement. It defines the following constants and functions:
Return the magic string value used to recognize byte-compiled code files (.pyc files). (This value may be different for each Python version.)
Return a list of 3-element tuples, e... | <urn:uuid:89c60590-1408-4e00-81b2-bc5c4d3d755c> | 2.71875 | 2,233 | Documentation | Software Dev. | 44.016073 |
Joined: 16 Mar 2004
|Posted: Wed Apr 02, 2008 3:29 pm Post subject: Tiny tweezers and yeast help show how cancer drug works
|0 July 2007 EurekaAlert
Tiny tweezers and yeast help St. Jude show how cancer drug works
Researchers show that topotecan poisoning of topoisomerase causes cell death by forcing the accumulation o... | <urn:uuid:a94766b2-7950-45e8-a6ae-b080e7e22350> | 3.0625 | 1,758 | Comment Section | Science & Tech. | 26.45857 |
AS WE flew over the Pacific Northwest of the US, I reflected on the contrast between the views before me. Ahead was that engineering triumph, a flexing wing of a jet. But beneath me the chequerboard of recently cleared forest was a dramatic reminder that, despite our technological advances, humans are still raiding nat... | <urn:uuid:8c30c9e2-816b-4c1d-9473-aa1dc73c2c87> | 2.96875 | 211 | Truncated | Science & Tech. | 42.761085 |
Everyone has heard of Darwin -- he gets most of the credit for the theory of evolution. And while he deserves to be recognized for his contributions, of course, he couldn't have gotten there on his own.
In this segment, we'll talk with biologist Sean Carroll about the flora, fauna, fossils, and scientists that, over th... | <urn:uuid:0141afc1-458f-4d9c-b94b-42621f9e6083> | 2.6875 | 256 | Truncated | Science & Tech. | 41.338796 |
Web edition: October 31, 2012
She was born, like all hurricanes, as a faintly inauspicious stirring of winds. But she didn’t come from off the coast of Africa, as many tropical Atlantic storms do. She was a child of the Caribbean.
On the evening of October 19, a trough of low air pressure drifted slowly in the Caribbea... | <urn:uuid:3e26ddf3-7913-4543-a364-2adef4c51eb3> | 3.21875 | 1,518 | Knowledge Article | Science & Tech. | 53.311641 |
Homo sapiens may not have been responsible for the five distinct spasms of extinctions in geological time that began an estimated 440 million years ago, but humans are centrally implicated in the ongoing sixth wave of severe biodiversity loss. The Convention on Biological Diversity (CBD) was drafted in 1992 to stem the... | <urn:uuid:7ece3f79-d620-45a8-bdac-0f5bc65d8b0c> | 3.359375 | 504 | Nonfiction Writing | Science & Tech. | 23.343049 |
We removed non-native fish from a section of the river and the endangered native species humpback chub increased in abundance. But it is not yet clear that decreased competition explains the rebound in population.
Using genetic analysis of organic material found in aquatic environments it is possible to detect the pres... | <urn:uuid:22715960-9d45-4c19-8c69-40e25d325b19> | 3.09375 | 255 | Content Listing | Science & Tech. | 20.600664 |
The basis of this article is especially written for the Coastal Wiki by the main author referred to at the bottom of this page.
Natural shoreline mechanisms
Uprush and backwash
The transport of sediment across the beach face is performed by wave uprush and backwash. The uprush moves sand onshore while the backwash tran... | <urn:uuid:e81e3e67-18b4-4e11-a0d9-8faec97e7955> | 3.5 | 945 | Knowledge Article | Science & Tech. | 37.602348 |
Just say you were writing a calculator and when the user clicks 7 it puts 7 in a edit control, then say the user clicks 8 you want it to put the 8 next to the 7. insted of clearing the 7 and putting an 8.
How is this done. is there a WM_ or a ES_ because at the moment i cant find one. i have searched everywhere. The wa... | <urn:uuid:f47de8bf-e064-471b-acad-4e6f9b111904> | 2.953125 | 248 | Comment Section | Software Dev. | 85.127418 |
powerful space explosion may herald star's death by black hole
"a huge, powerful star explosion detonated in deep space last week — an ultra-bright conflagaration that has astronomers scratching their heads over exactly how it happened.
the explosion may be the death cry of a star as it was ripped apart by a black hole... | <urn:uuid:8a81d43b-5eaa-4447-a191-749db357a593> | 2.71875 | 248 | Comment Section | Science & Tech. | 41.995568 |
Hubble Space Telescope
The Hubble Telescope: Star Birth
Buy Astronomy Posters At AllPosters.com
The Hubble Space Telescope - a joint ESA/NASA project - is a 2.4-meter reflecting telescope which was deployed in low-Earth orbit (600 kilometers) by the crew of the space shuttle Discovery (STS-31) on 25 April 1990. During ... | <urn:uuid:7293063e-3a2a-47cb-8c96-95d4a4f52fb4> | 3.921875 | 1,020 | Knowledge Article | Science & Tech. | 34.336001 |
Operators are used as a means for object composition and embedding. Simple parsers may be composed to form composites through operator overloading, crafted to approximate the syntax of an Extended Backus-Normal Form (EBNF) variant. An expression such as:
a | b
actually yields a new parser type which is a composite of i... | <urn:uuid:36bf1b25-5a1a-43f2-9b1c-6dbdabd38474> | 3.875 | 1,248 | Documentation | Software Dev. | 53.35573 |
Yes, you read that right. Data collected by NOAA reveal that the month of March saw a total of 7,755 daytime and 7,515 nighttime record-breaking high temperatures, making last month far and away "the warmest March on record."
The video featured up top shows the locations of each daytime and nighttime record (or tied re... | <urn:uuid:39b25f31-7316-48d8-bd09-4a7eb2892d4b> | 2.828125 | 441 | Listicle | Science & Tech. | 54.976095 |
The diagram below has rotational symmetry. How many regular pentagons are there?.
Please help to get the solution. Please find Attached
I don't see those. The central pentagon is formed with quadrilaterals, isn't it? If the question is about rotational symmetry, then perhaps we're supposed to get five pentagons from ea... | <urn:uuid:15767da7-7cc9-42b0-a79c-bef58588ca85> | 3.34375 | 132 | Q&A Forum | Science & Tech. | 66.954545 |
Submarine canyons are dominant features of the outer continental shelf and slope of the US East coast from Cape Hatteras to the Gulf of Maine. Click image for larger view and image credit.
The Science of Deep-water
Submarine canyons are dominant features of the outer continental shelf and slope of the US East coast fro... | <urn:uuid:97b2df46-f0b5-49ef-80e7-1e8ce5b0381d> | 3.515625 | 1,159 | Knowledge Article | Science & Tech. | 21.341261 |
Paper airplanes are like real airplanes in their basic physics. Some points:
They should be mildly nose-heavy. (The tail actually presses downward, to counteract the nose-heaviness.) If they are too nose-heavy, they will just arrow into the ground.
If they are tail heavy, they will go up, and then slide backward.
If th... | <urn:uuid:2b53760c-1d66-4a16-a2dd-4c72e199bcd0> | 3.109375 | 389 | Q&A Forum | Science & Tech. | 69.662821 |
Mixins are one of Ruby's defining features, but often one of the most difficult to understand for those new to Ruby. They're not difficult to understand, but they're not something most programmers have encountered before as most languages don't have mixins. A mixin is a way for code to be shared across multiple classes... | <urn:uuid:06873574-ced8-45fb-9182-7f78cee32b70> | 3.578125 | 656 | Knowledge Article | Software Dev. | 41.056783 |
Naomi Ginnever - Photobiology & Solar Radiation
University of St. Andrews, United Kingdom
Does Exposure Time and Different Wavelengths of Light Effect the Photobleaching
of Colored Dissolved Organic Matter (CDOM)?
Colored Dissolved Organic Matter (CDOM) absorbs wavelengths in the ultraviolet (UV) and visible portions o... | <urn:uuid:ced7b4c0-f97d-4200-ab3f-2b910137cff2> | 2.953125 | 396 | Academic Writing | Science & Tech. | 34.031532 |
Don’t they seem so serene sparkling away in the night sky?
It’s a shame but we all know that’s not always been the case.
It is generally thought that stars form in a violent reaction between gas particles when dense parts of molecular clouds collapse from their own gravity (for more information on star formation check ... | <urn:uuid:a5d0097e-25c7-4479-883f-60346ccc1b6c> | 3.390625 | 544 | Personal Blog | Science & Tech. | 51.559943 |
My Thanks to Ned Nikolov, who has just sent the first part of the ‘Response to comments on the Unified Theory of Climate’ to us.
Part 1: Magnitude of the Natural ‘Greenhouse’ Effect
Ned Nikolov, Ph.D. and Karl Zeller, Ph.D.
January 17, 2012
We’ve decided to split our expanded explanation into two parts, so that we do n... | <urn:uuid:2ebeba28-a1b1-4bb2-8c81-89d0ab9bcc70> | 2.71875 | 498 | Comment Section | Science & Tech. | 57.058333 |
Bucky Fuller (1895-1983) is widely recognized as one of the
world’s great modern visionaries of the 20th century. He was a
natural Futurist, not because of his intellect, but his wisdom to
challenge widely held assumptions from the world around him.
He blended his skills as a writer, thinker, and engineer into a
concep... | <urn:uuid:d41d5a2a-4025-43ff-a509-ab6ae5844285> | 2.703125 | 1,686 | Personal Blog | Science & Tech. | 35.550579 |
Thanks to the wonders of the Internet, it’s easier than ever to participate in and contribute to important space research while having fun at the same time. Whether you’re interested in searching for E.T. or want to help scientists better understand stars, there are innovative sites available today that let you contrib... | <urn:uuid:2ee1d12d-d543-4ded-8329-47de4769821e> | 3.109375 | 587 | Listicle | Science & Tech. | 42.314969 |
Bumblebees do things differently: unlike honeybees, they do not have a permanent colony. In autumn, a bumblebee colony dies out and only the young, mated queens hibernate each separately in the soil. In spring, a queen starts a new colony. She lays a first batch of eggs, from which larvae emerge after 4 to 5 days.
In t... | <urn:uuid:71bdf485-77d1-4656-95b7-acd890d00b81> | 3.875 | 194 | Knowledge Article | Science & Tech. | 65.540802 |
Both arithmetic (built-in) and user-defined numeric types require proper
(that is, with (in-class) integral constants).
The library uses
std::numeric_limits<T>::is_specialized to detect whether the type
is builtin or user defined, and
std::numeric_limits<T>::is_signed to detect whether the type is
integer or floating p... | <urn:uuid:f4550be3-5da9-4fa5-a1c4-86e95e76ec91> | 2.703125 | 640 | Documentation | Software Dev. | 28.8983 |
The Earth's End
Date: 1993 - 1999
Where does the earth end?
Right beneath your feet! Really, the only meaning to "end" on
the earth is the boundary between the inside (underground)
and the outside (into the atmosphere and space). Other than that,
the earth is pretty much spherical, so there isn't any place
on earth tha... | <urn:uuid:48da4693-7b10-4c5d-9623-06107f3513d0> | 3.671875 | 176 | Knowledge Article | Science & Tech. | 50.83897 |
I recently attended the World Climate Conference-3 (WCC-3), hosted by the World Meteorological Organization (WMO) in Geneva. Most of the talk was of providing “climate services” (CS) and coordinating these globally. But what are climate services, and how much of what was envisaged is scientifically doable?
Climate serv... | <urn:uuid:7e076c46-f3dc-48eb-8e3e-874ec8edc669> | 2.953125 | 904 | Knowledge Article | Science & Tech. | 31.575573 |
Of the eight species of the Tetragonostachys that occur in Africa and on Madagascar only the species
Selaginella wightii occurs outside of the area in southern India and on Sri Lanka. Understandably the African and
Asian populations have been classified into two varieties based upon the degree of cilia on the sporophyl... | <urn:uuid:7db23c0b-eb7a-4962-8f12-93ac503b2f4c> | 2.828125 | 931 | Comment Section | Science & Tech. | 63.877114 |
PHILADELPHIA â When semiconductor nanorods are exposed to light, they blink in a seemingly random pattern. By clustering nanorods together, physicists at the University of Pennsylvania have shown that their combined âonâ time is increased dramatically providing new insight into this mysterious blinking behavior.
The re... | <urn:uuid:9c33333e-73fc-480b-ad2c-3095d7eca77a> | 3.125 | 1,109 | Knowledge Article | Science & Tech. | 28.563994 |