text large_stringlengths 148 17k | id large_stringlengths 47 47 | score float64 2.69 5.31 | tokens int64 36 7.79k | format large_stringclasses 13
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Gene expression - different levels in different cells
Professor Rusty Lansford explains that all genes are not expressed in the same levels in different cells; there is a lot of differential regulation.
From what I understand at this point in time is that there are 25-30 thousand genes that are described by the genomic... | <urn:uuid:0a921beb-9df7-444d-b07e-9f4e70fcafd7> | 2.765625 | 353 | Audio Transcript | Science & Tech. | 46.1825 |
Occluded fronts form mainly when a cold front catches a warm front. They are characterized on weather maps as purple lines with alternating triangle and half circle pips. In all cases they symbolize a dying front. A cold type occluded front is characterized by very cold air catching cool air with warm air trapped in th... | <urn:uuid:26138570-b12d-442a-9c97-548b96b0116f> | 3.140625 | 132 | Knowledge Article | Science & Tech. | 65.685538 |
Much world attention has been focused on the issue of climate change and the impacts it may have on our environment, biodiversity and people.
Some science links climate change to factors involving greenhouse gasses such as carbon dioxide which is absorbed by plants and stored in very substantial quantities in trees and... | <urn:uuid:27083780-2fe1-425a-9f14-1a98e77a1226> | 3.609375 | 484 | Knowledge Article | Science & Tech. | 28.029894 |
O'Reilly Book Excerpts: Java RMI
Java RMI: Serialization
This excerpt is Chapter 10 from Java RMI, published in October 2001 by O'Reilly.
Serialization is the process of converting a set of object instances that contain references to each other into a linear stream of bytes, which can then be sent through a socket, sto... | <urn:uuid:439e9664-bafc-4cd0-9e5e-692087138423> | 3.046875 | 2,047 | Documentation | Software Dev. | 44.476712 |
|Mar15-12, 07:11 AM||#1|
Angular vel. and mom.--origins vs. axes
This is a conceptual question.
Angular velocity is measured with respect to an axis, correct?
Yet angular momentum is measured with respect to an origin, i.e. a point, correct?
For angular momentum problems where only the magnitude of angular momentum cha... | <urn:uuid:743825af-26f9-49bf-bad3-ff9403c2c3a1> | 2.9375 | 210 | Comment Section | Science & Tech. | 53.795635 |
Jan. 17, 2012 Preserving diverse plant life will be crucial to buffer the negative effects of climate change and desertification in in the world's drylands, according to a new landmark study.
The findings of the multi-author study, published January 13 in the journal Science, are based on samples of ecosystems in every... | <urn:uuid:d29efce7-ecf2-493b-813e-23084dcf66df> | 3.671875 | 936 | Truncated | Science & Tech. | 45.769789 |
|Weather Review - June 26, 2009
The above image is a visible satellite captured at 1215 pm CDT. As evident by the clouds through south central Mississippi, central Alabama and central Georgia, there is a weak boundary which has been the focus for convection over the last couple of days. The green lines are isobars of g... | <urn:uuid:51d10f16-e3a7-4228-9940-1b26df16b56e> | 2.828125 | 325 | Knowledge Article | Science & Tech. | 65.920897 |
Dictyoptera (from Ancient Greek diktuon "net" + pteron "wing") includes three groups of polyneopterous insects - cockroaches (Blattaria), termites (Isoptera) and mantids (Mantodea). While all modern Dictyoptera have short ovipositors, the oldest fossils of Dictyoptera have long ovipositors, much like members of the Ort... | <urn:uuid:0bb9e2f5-67df-41fa-a4f3-3e1a5c4ac972> | 3.359375 | 703 | Knowledge Article | Science & Tech. | 42.381927 |
In a German lab, Johannes Stokl is wafting a series of fruity and yeasty smells in front of a panel of restrained testers. As the chemical cocktail tickles their senses, electrodes and brain scanners record their every reaction. This bizarre wine-tasting event is all part of a study into the bizarre deception of a flow... | <urn:uuid:62c3a199-432f-4bc6-855d-1633669e386f> | 3.015625 | 1,032 | Nonfiction Writing | Science & Tech. | 52.343927 |
Brief SummaryRead full entry
BiologyLike many crocodilians, the African slender-snouted crocodile is apparently a rather shy and timid reptile (6), and despite being a remarkably agile swimmer (6), it is often found resting in the shade of trees (8). It is the only crocodilian species known to climb as high as several ... | <urn:uuid:008ebb02-2384-4e0e-8d06-ff34b2bf4e3b> | 3.875 | 392 | Knowledge Article | Science & Tech. | 45.836061 |
Zhang, M. H., W. Y. Lin, S. A. Klein, J. T. Bacmeister, S. Bony, R. T. Cederwall, A. D. Del Genio, J. J. Hack, N. G. Loeb, U. Lohmann, P. Minnis, I. Musat, R. Pincus, P. Stier, M. J. Suarez, M. J. Webb, J. B. Wu, S. C. Xie, M.-S. Yao, and J. H. Zhang, 2005: Comparing clouds and their seasonal variations in 10 atmospher... | <urn:uuid:c88390d0-8853-4ddf-9aae-18fa6e13c8e6> | 2.90625 | 537 | Academic Writing | Science & Tech. | 50.138878 |
JF Ptak Science Books Quick Post
Even though masses of people had been used in panoramic photography for some years (thousands of people, usually soldiers, gathered to form a living liberty bell, or portrait of George Washington, or some such thing) , I cannot recall the use of humans as a direct statistical aid as in ... | <urn:uuid:10358e39-cd67-4c7a-8b50-4555b5a8e4a0> | 2.875 | 319 | Personal Blog | Science & Tech. | 46.972702 |
Open Sound System
|Do you have problems with sound/audio application development? Don't panic! Click here for help!|
All OSS system calls follow the familiar Posix/Unix semantics. Please look at the standard manual page (
man select or
man poll) for more informtion. This section will only explain some OSS related detai... | <urn:uuid:bb8f679d-7656-455b-9e76-8895d1caca2e> | 2.734375 | 579 | Documentation | Software Dev. | 53.340081 |
Java programming resources
I am a Java programmer. I have successfully done some secret key encryption and decryption. I can use the private key to sign a message and verify with the public key, but I still need some coding examples on how to encrypt with the public key and decrypt with the private key or vice versa. C... | <urn:uuid:870534bb-2cd3-4bcc-afec-81e62ee3291e> | 3.046875 | 453 | Q&A Forum | Software Dev. | 55.244657 |
Technology that Shapes Our Lives
September 23. 1999
After a more than 9 months, the Mars Climate Orbiter arrived at Mars on schedule, on September 23, 1999, in order to be inserted into Mars orbit. After Mars Orbit Insertion (MOI), the spacecraft was intended to become the first interplanetary weather satellite. Mars C... | <urn:uuid:89d35b05-91e2-4e4e-a091-528377255e4b> | 3.796875 | 250 | Knowledge Article | Science & Tech. | 40.208373 |
Carbon-Rich Extrasolar Planet Discovered might harbor diamond
This artist’s concept shows the searing-hot gas planet WASP-12b (orange orb) and its star. NASA’s Spitzer Space Telescope discovered that the planet has more carbon than oxygen, making it the first carbon-rich planet ever observed. Our planet Earth has relat... | <urn:uuid:fe0d2687-b48f-4ef2-a91b-8edc768789f7> | 3.875 | 271 | Truncated | Science & Tech. | 49.743045 |
Science Fair Project Encyclopedia
|Mission Name:||Gemini 11|
|Call Sign:||Gemini 11|
|Launch:||September 12, 1966|
|Landing:||September 15, 1966|
|Duration:||2 days, 23 hours|
|Distance Traveled:||~1,983,565 km|
|Gemini 11 Crew|
Gemini 11 (officially Gemini XI) was a 1966 manned spaceflight in NASA's Gemini program. It... | <urn:uuid:20499810-6b8f-4af4-8e73-cd7239258e58> | 3.359375 | 1,034 | Knowledge Article | Science & Tech. | 57.182143 |
Hale's spectroheliograph set-up occupied an area over 30 feet long consisting of an exterior light collection apparatus and a small building. The collected beam was directed into the building through a hole in the wall and inside the building were the mirror, the apparatus holding the two slits, the diffraction grating... | <urn:uuid:e6aec8cd-ddd7-4539-bdda-9ba1f944b8f8> | 3.859375 | 307 | Academic Writing | Science & Tech. | 26.138219 |
Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °
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I don´t know how to explane it. When i put in Mathematica a and b 45deg (a=b=45deg)
I'm very interested in knowing what c stands for?
At first i... | <urn:uuid:36c0c78a-787c-4858-b082-47426f508eb5> | 2.75 | 268 | Comment Section | Science & Tech. | 87.213333 |
Robert Angus Smith, an English chemist, first used the phrase "acid rain" in 1852 when he noted the connection between London's polluted skies and the acidity of its rainfall.
Most Scientists agree that "normal" rainfall has a pH of 5.6. Rain in the atmosphere reacts with carbon dioxide (CO2) to form a weak carbonic ac... | <urn:uuid:5996083a-4687-4884-820e-e0c8a62a8e04> | 3.40625 | 195 | Knowledge Article | Science & Tech. | 61.639288 |
“The great secret that all old people share is that you really haven’t changed,” wrote novelist Doris Lessing. “Your body changes, but you don’t change at all.” From a genetic point of view, there is a lot of truth in that statement: As we age, the core of our biological being — the sequence of our DNA, which makes up ... | <urn:uuid:503fb4fa-902e-426f-9d4c-c66eea613dfd> | 3.84375 | 1,100 | Content Listing | Science & Tech. | 37.775817 |
The test code can be run under a non-cluster kernel, but an error will occur if the tests are ran using the cluster protocol.
The server program times message throughput between multiple clients. You can run this with wither TCP/IP or cluster.
This is similar to the server test except only one client is used and only t... | <urn:uuid:532689ec-7023-42e7-8911-ccb3b632f237> | 2.828125 | 318 | Documentation | Software Dev. | 57.809555 |
1."The combination of cold temperatures and wind speed determine what is called wind chill. The wind chill is a temperature that is the still-air equivalent of the combination of cold and wind. When the Wind speed is 25mph, the wind chill depends on the temperature t (in degrees Fahrenheit) according to
WC= 1.479t - 43... | <urn:uuid:e680a7d1-de0e-4906-a6ed-99407dc69693> | 3.453125 | 291 | Q&A Forum | Science & Tech. | 92.207463 |
XCOR and ATK developed this prototype LOX/methane rocket engine as a stepping stone to NASA's original Orion CEV manned spacecraft and return to the moon and manned mission to Mars plans. These envisioned a shift to methane propulsion, since methane could be extracted from the Martian atmosphere. The 5M15 was based on ... | <urn:uuid:84fc5779-eb86-4618-b8e8-d7c4a279244d> | 2.734375 | 360 | Knowledge Article | Science & Tech. | 39.240313 |
Temperature is a quantity that determines when objects are in
thermal equilibrium. The flow of energy that occurs between two
objects or systems due to a temperature difference between them is
called heat flow. If heat can flow between two objects or systems,
the objects or systems are said to be in thermal contact. Wh... | <urn:uuid:5117389f-377b-4b45-9e52-855a85c06e94> | 4.1875 | 177 | Knowledge Article | Science & Tech. | 43.103043 |
A sequence is an ordered list of numbers:
3, 6, 9, 12, ....
1, 3, 5, 7, ...
A sequence can be thought of as a list of numbers written in a definite order:
a1, a2, a3, ..., an, ...
The number a1 is called the first term, a2 is the second term, and in general an is the nth term.
The terms of a sequence often follow a par... | <urn:uuid:ce42b3ba-14ca-4df1-9616-51ae66b0649c> | 4.375 | 179 | Knowledge Article | Science & Tech. | 85.982101 |
Photo Courtesy Ewan Wolff
Ewan Wolff holds a crocodile displayed at the annual
conference of the Wildlife
Disease Association. The conference was held in Australia where crocodiles are raised for meat and leather.
"There's a lot of stuff you can
read about, but it's a lot more useful to actually see what they do."
DEAD... | <urn:uuid:bb99e284-5b53-40a6-9a22-808f3b0ea995> | 3.109375 | 1,278 | Nonfiction Writing | Science & Tech. | 42.132196 |
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The Difference Between Plants And Animals
Tue Jan 22 09:26:29 GMT 2013 by Eric Kvaalen
"Why don't [animals] do what plants do, and get their energy straight from sunlight? The short answer is that many do."
The short answer is that most animals need more energy than what they can get fro... | <urn:uuid:146d3d27-815b-4ff0-b764-fa10e3770e98> | 2.6875 | 123 | Comment Section | Science & Tech. | 71.62625 |
|Nov28-12, 09:49 AM||#1|
Origin of IR radiation in living things ?
I've been reading that in a relatively normal environment about 1/2 of human heat loss is due to radiation. Most of this seems to have a wavelength of 10-12 μm.
Could someone here speak to the molecular origin of this? I'm guessing it is mostly from wat... | <urn:uuid:aa5e5587-896e-4db9-b678-ed3fdd607cf3> | 2.84375 | 307 | Comment Section | Science & Tech. | 59.333678 |
Summer rains have remained steady over the past 20 years, but are less than historic highs. Temperature has increased, and while the farmland per person is decreasing, population growth has been offset with improved yields.
While summer rains have increased during the past 20 years, temperatures have increased as well,... | <urn:uuid:f78999d6-16f9-4248-90b7-212907af20aa> | 3.21875 | 163 | Knowledge Article | Science & Tech. | 31.355401 |
Ohio 50-Meter Wind Map
The U.S. Department of Energy's (Energy Department's) Wind Program and the National Renewable Energy Laboratory published a 50-meter height wind resource map for Ohio. This map is a key piece of understanding the state's wind resource potential from a development, policy, and a jobs and economic ... | <urn:uuid:e6f8ab71-88ba-4b6e-8887-ef783ca476d2> | 3.171875 | 363 | Knowledge Article | Science & Tech. | 39.175484 |
Eddies and currents in this metallic outer ocean produce Earth's magnetic field. "At least we believe that, though we don't understand exactly what the mechanism is," said Richard Terrile, a planetary astronomer at the Jet Propulsion Laboratory in Pasadena, California, and a science consultant for the film.
So can the ... | <urn:uuid:2d8a5252-6c03-4813-9ff2-5f10fc7ed087> | 3.375 | 333 | Comment Section | Science & Tech. | 48.112505 |
2500 years ago, the ancient Greek astronomer Hipparchus classified the brightnesses of visible stars in the sky on a scale from 1 to 6. He called the very brightest stars in the sky “first magnitude”, and the very faintest stars he could see “sixth magnitude”. Amazingly, two and a half millenia later, Hipparchus's clas... | <urn:uuid:9360d0b8-aea4-4e1e-9b22-89feedca65d3> | 4.625 | 738 | Knowledge Article | Science & Tech. | 52.830476 |
Stats objects have the following methods:
When more than one key is provided, then additional keys are used as
secondary criteria when there is equality in all keys selected
before them. For example,
sort_stats('name', 'file') will sort
all the entries according to their function name, and resolve all ties
(identical f... | <urn:uuid:2c1c2351-9b17-46ab-9783-b7f89c7f4938> | 2.765625 | 572 | Documentation | Software Dev. | 51.96157 |
The effect of initial temperatures from about 300 degrees to 700 degrees K on the laminar burning velocity of hydrogen-air mixtures was determined from schlieren photographs of open flames. The temperature was raised in two ways: (1) by preheating of the hydrogen-air mixtures and (2) by simulated adiabatic preburning o... | <urn:uuid:e10362f5-0f75-43ca-a907-8c89facc5235> | 3.296875 | 359 | Academic Writing | Science & Tech. | 60.887385 |
Unit 7: Atmospheric Stability and Instability
A Summary: Atmospheric Lapse Rates and Stability
We all know that air in the atmosphere is constantly circulating. Indeed, the troposphere’s convection currents are much like those in a kettle of boiling water. The earth, which absorbs radiant energy from the sun and then r... | <urn:uuid:e59164a9-799b-454b-8458-7dcb97842005> | 4.25 | 819 | Knowledge Article | Science & Tech. | 51.186131 |
Book author and Discover blogger Carl Zimmer criticizes those who wrote about a recent Science paper, saying essentially: “Enhancers aren’t junk DNA, and nobody who knows what enhancers are ever thought so.”
They took their cue from the headline of the press release. Oops.
An enhancer is essentially a control button on... | <urn:uuid:60cc40e4-60c0-49e4-97a3-7d6f6ab2a5da> | 2.6875 | 342 | Personal Blog | Science & Tech. | 46.707795 |
The newly opened Center for PostNatural History in Pittsburgh is the first museum that seeks to catalog man-made biological organisms. The man behind the museum is not a scientist, but an artist, one member of a growing DIY community that is exploring–and making–a new meaning of life as we know it. Read the story below... | <urn:uuid:6e6d35be-b025-4804-9bc6-134b83f6ce56> | 2.890625 | 3,235 | Nonfiction Writing | Science & Tech. | 36.52986 |
Friday, August 20, 2010
From the size and shape of the beak, researchers have always known that the massive South American "terror bird" was a predator. Now they know precisely how the bird killed — wielding its huge skull and hooked beak like an pickax and repeatedly chopping at prey until it succumbed.
The 5-foot-tal... | <urn:uuid:4a5060e6-60a7-4ac4-991d-f84112b86333> | 2.890625 | 139 | Personal Blog | Science & Tech. | 51.422484 |
Hippie $hit or for real? Who cares as long as it snows…
From extreme drought, heat waves and floods to unprecedented tornado outbreaks, hurricanes, wildfires and winter storms. A record 12 weather and climate disasters in 2011 each caused $1 billion or more in damages — and most regrettably, loss of human lives and pro... | <urn:uuid:b7bf7b04-a953-4d11-bfae-d1a7dbbfed82> | 3.421875 | 429 | Listicle | Science & Tech. | 55.283292 |
Let's Talk with David Bromwich about Meteorology in the Poles
Dave Bromwich studies meteorology in the Arctic and Antarctic, looking at how weather systems in polar areas interact with the global climate system. Dave uses computer models to investigate how changes in Antarctic climate can cause changes in climate elsew... | <urn:uuid:f3c933b9-7c4c-4f1e-86f0-4e00dc7dbd74> | 2.875 | 2,036 | Audio Transcript | Science & Tech. | 44.452991 |
On starry grains
30,000,000 x 50 x 5 = 7.5 billion cubic meters of sand.
A grain of sand is about 0.1 mm across, so there are 10,000 per meter or 10,000 x 10,000 x 10,000 (or 1,000 billion) per cubic meter.
So we are talking (oh so very very roughly) about 7500 billion billion grains of sand along our Australian coastl... | <urn:uuid:c0d79af2-fb1a-4310-a1fc-7bc87920380a> | 3.453125 | 556 | Personal Blog | Science & Tech. | 72.683442 |
T. P. Kirkman
Simply begin typing or use the editing tools above to add to this article.
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contribution to combination theory
...into subsets, such that the blocks in any subset contain every treatment exactly once. For the... | <urn:uuid:1e449f9c-9322-42bf-86d8-d47c17ac0a0f> | 2.921875 | 160 | Knowledge Article | Science & Tech. | 74.896349 |
The function x = (5.4 m) cos[(4pi rad/s)t + pi/2 rad] gives the simple harmonic motion of a body. At t = 1.9 s, what are the (a) displacement, (b) velocity, (c) acceleration, and (d) phase of the motion? Also, what are the (e) frequency (in Hz) and (f) period of the motion?
please provide explanation, i keep getting th... | <urn:uuid:381f1e7b-95e7-4f3a-9336-4b944ddda4de> | 2.796875 | 107 | Q&A Forum | Science & Tech. | 87.997273 |
A.A. Penzias and R.W. Wilson were conducting radio astronomy experiments with the ultra-sensitive horn antenna at Crawford Hill, but were frustrated by a noise in its receiving system, a noise that remained constant no matter which direction they scanned. This made no sense and they suspected that it came from bird dro... | <urn:uuid:4b0bff21-65e9-4923-93da-6076b1ca5885> | 3.171875 | 131 | Knowledge Article | Science & Tech. | 46.197693 |
Private Sub Command1_Click() Dim a As String Dim B As String a$ = Text1.text 'Text to encrypt B$ = Text2.text 'Password 'encrypting text with a return to text1 Text1.text = Encrypt(a$, B$, True) 'true = Encrypt End Sub
Explanation : Command1 is a Command Button used to Encrypt text
Private Sub Command2_Click() Dim a As... | <urn:uuid:2db9c7b0-77bf-4ab0-aa80-68ff32bc623c> | 3.28125 | 911 | Documentation | Software Dev. | 50.611299 |
nitro group, in chemistry, functional group that consists of a nitrogen atom joined to two oxygen atoms. Compounds that contain a nitro group, e.g., picric acid and trinitrotoluene (TNT), are called nitro compounds; many nitro compounds are unstable and are used as explosives. As a result of the chemical bonding in the... | <urn:uuid:969991e6-2b2a-4e86-a4e1-6828e3f549fa> | 3.3125 | 174 | Knowledge Article | Science & Tech. | 33.574571 |
Bartusiak, Marcia F., Burke, Barbara, Chaikin, Andrew, Greenwood, Addison, Heppenheimer, T.A., Hoffman, Michelle, Holzman, David, Maggio, Elizabeth J., Moffat, Anne Simon. "2 A Positron Named Priscilla: Trapping and Manipulating Atoms." A Positron Named Priscilla: Scientific Discovery at the Frontier. Washington, DC: T... | <urn:uuid:c99cc483-84d4-411b-9fc6-e9dab2f2fe4e> | 3.5625 | 667 | Academic Writing | Science & Tech. | 33.726283 |
Type Ia Supernovae
Update: Recent Berkeley Lab Computing Sciences News about supernovae: read more...
Key Challenges: Understanding Type Ia supernovae (SNe Ia) from first principles is difficult because simulation results are quite sensitive to how the thermonuclear runaway is ignited (e.g., at the center or slightly o... | <urn:uuid:fa3b3e25-2d7f-41e2-9b39-712285d6db7f> | 3.203125 | 537 | Knowledge Article | Science & Tech. | 30.357167 |
WITH CRUCIAL HELP FROM LEMIEUX, RESEARCHERS ANSWERED A LONG-STANDING QUESTION ABOUT THE PERMEABILITY OF BIOLOGICAL CELLS.
If you could travel through the body, a swamp boat might be a good vehicle. Each of us is a walking, talking Everglades, about 75 percent water, and we can't survive for more than a few days without... | <urn:uuid:5dd89f6b-c406-4d9e-b289-643d71a34195> | 3.546875 | 1,930 | Knowledge Article | Science & Tech. | 33.222984 |
…continuedThe Chance of Finding Aliens
Let's reevaluate the Drake equation by analyzing each term separately. R, the rate of star formation in the Milky Way per year, is indeed currently about 1 astronomers are quite sure of that. In fact, astronomers have recently determined that stars formed at a higher rate several ... | <urn:uuid:30874f98-4aec-42b9-95b6-9ff44da72e54> | 3.3125 | 479 | Knowledge Article | Science & Tech. | 49.806087 |
The International Energy Agency’s World Energy Outlook 2010 was released this week. Among the take-aways of the Executive Summary that are germane to climate change courses, based on the Agency’s “New Policies” central scenario for energy use and GHG emissions:
- World energy demand is projected to grow by 1.2% annuall... | <urn:uuid:7a300231-51d1-447c-b276-8e00a3b564a6> | 2.734375 | 550 | Personal Blog | Science & Tech. | 30.788444 |
During this same timeframe, the southern San Andreas fault has only produced a couple moderate earthquakes, the 6.5 Desert Hot Springs earthquake in 1948, and the 1986 6.2 earthquake near Palm Springs. However, both the San Andreas and San Jacinto have similar long term slip rates, which implies that the San Andreas fa... | <urn:uuid:a0ae8e11-7541-4730-8e96-ebc392cde49a> | 3.640625 | 167 | Knowledge Article | Science & Tech. | 67.771825 |
The most illustrative examples of vegetation zonation are found in locations where environmental conditions vary strongly at a shortdistance. Here below this phenomenon is lined out for coastal and a high mountain vegetation. Zonation, though in a less pronounced way, can be found in the district of Nijmegen along the ... | <urn:uuid:b1e7908a-847a-48aa-ba4c-dab04540471d> | 3.4375 | 607 | Knowledge Article | Science & Tech. | 29.398621 |
Surface Integrals (continued)
Also note the partial derivatives ru = ∂ r / ∂ u and rv = ∂ r / ∂ v
Now the element of surface area is dS = | ru du x rv dv | = | ru x rv | du dv
but ru x rv = N = normal to the surface, S and du dv = dA
So the relation between the element of surface area, dS, and the element of area, dA
d... | <urn:uuid:be49dbc0-2cce-428c-9f6e-6afad0bf461d> | 3.171875 | 367 | Tutorial | Science & Tech. | 81.089706 |
Hello, Frank Indiviglio here. Early spring is a favorite time for amphibian enthusiasts. Here in the northeastern USA, a spectacular event is unfolding, as Wood Frogs, Tiger and Spotted Salamanders, Spring Peepers and others head en masse for their breeding ponds. I’ve been visiting one pond, first shown to me by herpe... | <urn:uuid:190c9034-80cc-4a59-bb68-16b6482b456b> | 2.890625 | 656 | Personal Blog | Science & Tech. | 31.723455 |
The leaking bucket equation for the water level
is the unit step function. The solution is easily seen to be
and says that
is zero for
(because the bucket is empty then). In this Demonstration, we replace the exact solution by a numerical one, which is obtained by repeated application of a so-called integrator (actuall... | <urn:uuid:201095c8-ea90-4fda-bdd1-9278fc276c5b> | 3.375 | 255 | Tutorial | Science & Tech. | 37.124359 |
The Alsco long-fingered frog is named after the company that funded the expedition that led to its formal discovery: American Linen Supply Company (ALSCO). This small tan, black, pink and blue frog is found in streams surrounded by remnant areas of forest, where it breeds and spends much of its time hiding under large ... | <urn:uuid:d6b7b339-c906-447d-8067-f8d4601f9ca2> | 3.015625 | 172 | Knowledge Article | Science & Tech. | 29.173685 |
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Nanotechnology bears the promise of engineering at an atomic
scale--of assembling atoms in arrangements that are completely
unnatural, thereby creating material... | <urn:uuid:43878757-6855-4ddb-9da2-32c1dc43ba59> | 3.953125 | 352 | Content Listing | Science & Tech. | 36.774635 |
Fireflies are a family of beetles called the Lampyridae. These beetles are special in that most of them have bioluminescence, the ability to produce light. They are sometimes called 'lightning bugs' or 'forest stars'. There are about 2000 different species, most of which are nocturnal.
Physical Characteristics [change]... | <urn:uuid:37c34e39-d7da-46d0-a459-b0d56debce65> | 4.1875 | 451 | Knowledge Article | Science & Tech. | 47.493908 |
Dissecting the Remnants of Nearby Supernova Explosions By Dr. Laura Lopez
Her lecture notes: Supernovae are the explosive ends of the lives of massive stars. They are the most energetic events in the Universe, and they produce almost all the elements in the periodic table. Although several hundreds of supernovae are fo... | <urn:uuid:64a95de9-6f05-4095-9574-c487d60623a7> | 2.921875 | 365 | Truncated | Science & Tech. | 64.307856 |
Learn more physics!
When you put an ice cube in a glass of water, filled up to the top what happens and why does it happen?
- Katie (age 15)
South WIndsor High School, connecticut
We assign this question all the time to our students. Since the ice,
when it floats, displaces exactly its weight in water, when it melts,
t... | <urn:uuid:88c21965-f951-447b-9486-cfb9f629ac74> | 3.6875 | 376 | Q&A Forum | Science & Tech. | 66.484081 |
Recreating Venus in the Lab
Venus and Earth are often described as sister worlds. However, the second planet from the Sun has obviously evolved in a very different manner from our Earth. The surface of Venus is very hot, with temperatures reaching 480 degrees Celsius, and its surface pressure is 90 times greater than o... | <urn:uuid:1bcff094-f48d-44ed-9ff7-cc0251e22e2b> | 4.0625 | 723 | Knowledge Article | Science & Tech. | 22.791648 |
One of the surprises of the Aosta conference was Joel Poncy’s presentation on a fast orbiter mission to Haumea. Poncy (Thales Alenia Space, France) and colleagues have been developing ideas for the extraordinarily difficult challenge of not just sending a probe to the outer system, but slowing it down for orbital captu... | <urn:uuid:b632af58-ce0f-4301-b8e2-470847de78f5> | 3.390625 | 989 | Personal Blog | Science & Tech. | 50.553049 |
Posted by iearn on Wednesday, January 24, 2007 at 11:03am.
can someone help me out with this one? balanced equation is:
2H2 + O2 > 2H2O
My questions are:
How many molecules of water are produced from 2.0 * 10 ^23 molecules of oxygen?
How many moles of water are produced from 22.5 moles of oxygen?
OK. First, it depends ... | <urn:uuid:6ad10f98-504d-4585-9895-a97c995be8b9> | 2.6875 | 696 | Q&A Forum | Science & Tech. | 93.752634 |
Jellyfish In the Chesapeake
Until the mid-196Os, hardly more was known about the sea nettle (Chrysaora quinquecirrha) than its basic biology, namely that it has two life stages, one where small, swimming larvae fasten to a surface and develop into fixed polyps, and a second where the mature polyps begin to bud off (str... | <urn:uuid:00d35aba-3796-4a71-ac09-d01be21931cb> | 3.421875 | 1,834 | Knowledge Article | Science & Tech. | 36.785816 |
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I also got an answer via email that I think is worth sharing.
I'm not answering officially as I’m probably wrong but…
The main point mentioned is that because flies have such a short
lifespan, so they should evolve faster than elephants or other slow
growing species. While this is true, and there are many examples of r... | <urn:uuid:a34488ee-a5b1-4d88-bb66-255dbe277074> | 3.171875 | 489 | Q&A Forum | Science & Tech. | 35.411909 |
Submillimeter Wave Astronomy Satellite (SWAS)
The Submillimeter Wave Astronomy Satellite (SWAS) was an astronomical observatory launched on December 5, 1998 as part of the Small Explorer program within NASA. Investigators at Smithsonian Astrophysical Observatory and Goddard Space Flight Center designed the telescope an... | <urn:uuid:3c05b94e-02cf-49b2-ac88-d223c211f643> | 3.21875 | 271 | Knowledge Article | Science & Tech. | 42.239226 |
- Operator (Visual Basic)
Returns the difference between two numeric expressions or the negative value of a numeric expression.
In the first usage shown in the preceding syntax, the – operator is the binary arithmetic subtraction operator for the difference between two numeric expressions.
In the second usage shown in ... | <urn:uuid:2c912697-a2ef-4ef3-8bbf-0767b3089c71> | 4.25 | 234 | Documentation | Software Dev. | 28.968406 |
Change Is In the Air
Posts have been weekly due to work and travel, but each week has brought more bad news for the old cosmology. Once upon a time the planets were thought to circle Earth in epicycles. Just as planets sometimes appear to move backwards in their orbits, large areas of the cosmic microwave background ar... | <urn:uuid:07894d35-e10b-49bf-acfc-cedbea735761> | 3.171875 | 397 | Personal Blog | Science & Tech. | 44.438651 |
Image courtesy of LBNL
To map the oceanic subsurface at a scale and resolution previously unknown, EMGeo unites the latest in computing power with advanced geophysical imaging techniques. In the image above, the blue regions contain hydrocarbon and salt – the hydrocarbon reservoir appears as a separate small, lenticula... | <urn:uuid:43a307bc-5a26-45ee-bfe9-3d8e70c4f6c4> | 3.203125 | 682 | Knowledge Article | Science & Tech. | 20.601738 |
On October 2, Nature published this news brief about a claim of a solution to the Navier-Stokes equations:
A buzz is building that one of mathematics’ greatest unsolved problems may have fallen.
Blogs and online discussion groups are spreading news of a paper posted to an online preprint server on 26 September. This pa... | <urn:uuid:dec345fd-a8c1-4448-bc1b-a2ca1b6b2940> | 2.828125 | 593 | Nonfiction Writing | Science & Tech. | 42.234704 |
and Cryptography? Logic, Common Sense, And Numbers
By Lewis E. Love
1. THE MIND READER
a. pick a number (don't disclose
it to the instructor)
b. add ten (10 ) to the number
c. multiply the number by
d. subtract six (6) from the
e. divide the number by two
f. subtract the original number
selected from the total
2. THE E... | <urn:uuid:781e7623-404c-4f9d-b9b2-9df866f02515> | 3.6875 | 282 | Tutorial | Science & Tech. | 78.266859 |
18 September 2010: "Climate Science" is often mentioned in the mainstream press as if it is a singular field. In reality, it combines elements of many scientific specialties, including theoretical and experimental physics, atmospheric science, meteorology and oceanography. As well, other fields such as engineering, eco... | <urn:uuid:f9b59c45-2238-450b-8b0b-7be0169c95eb> | 3.109375 | 491 | Knowledge Article | Science & Tech. | 21.702014 |
The Pauli Exclusion Principle states that no two electrons in the same atom can have the same set of quantum numbers. This set is made up of
- Principle quantum number n: this is the shell around the atom where the electron exists. The shells are represented by whole numbers. n can be 1,2,3....
- Orbital quantum number... | <urn:uuid:09a0f1dd-7598-481e-b6ee-3f11b8655518> | 3.984375 | 161 | Structured Data | Science & Tech. | 89.442396 |
With the help of one of the planet’s oldest marine organisms, an ANU scientist is revealing the natural environment’s true history. By LUCY WEDLOCK.
She may have grown up in Africa’s land-locked Republic of Uganda, but Aimée Komugabe has always felt the inescapable pull of the ocean tide.
But it wasn’t until after fini... | <urn:uuid:1613ed74-a873-4ab9-b053-c9e1cf97c254> | 3.46875 | 484 | Nonfiction Writing | Science & Tech. | 46.609537 |
WE LIKE to blame the weather for all manner of ills, but the fall of the western Roman empire?
A tree-ring history of European climate has uncovered several links between climate and the rise and fall of civilisations, including Rome. Climate was likely a factor alongside political failures and barbarian invasions, say... | <urn:uuid:54251ee5-426b-447b-a112-b087150f5d88> | 3.46875 | 202 | Truncated | Science & Tech. | 49.01315 |
Climate Change May Modify Half Earth's PlantsQuicklink submitted by Daniel Geery Permalink
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|Climate change will also drive the conversion of nearly 40% of land-based ecosystems from one major ecological community type - such as forest, grassland or tundra - toward another, according to a new NASA and unive... | <urn:uuid:04f9874d-d4f5-4969-b099-836232ceae5b> | 2.703125 | 123 | Truncated | Science & Tech. | 31.153 |
The Large Hadron Collider (LHC) has generated the enormous amount of 75 petabytes of physics data during the past three years, until today's February 14 maintenance shutdown. Computer engineers at CERN, the location of the world's very first web server, today announced that the CERN Data Centre has ...
CERN's LHC, whic... | <urn:uuid:cb375f5e-1c4c-4fbe-982d-43380c1b1656> | 2.90625 | 531 | Content Listing | Science & Tech. | 57.115737 |
Not long ago, Javasoft celebrated Java's third birthday. Java, once seen as merely another way to animate and spice up web pages, has become much more than that. Nowadays, well-known software corporations have pledged their support to Java, and new Java APIs are being defined in record time. The Java technology enables... | <urn:uuid:422de6d3-9075-4f29-8915-bdffe31ed1c9> | 2.859375 | 1,657 | Knowledge Article | Software Dev. | 47.570292 |
... >> Natural Science >> Genetics >> Fragile X-Chromosome
Highest Rated Sign
Nobody has posted a sign yet.
Definition: A type of Z chromosome containing a site toward the end of the long arm that ends to break in cultured cells that are starved for DNA precursors; causes fragile-X syndrome
Source: Essential Genetics: ... | <urn:uuid:163ea318-6e8f-4a7a-91b4-6c27776b15fd> | 2.890625 | 84 | Knowledge Article | Science & Tech. | 48.327158 |
The process by which an electromagnetic field causes an electron in an excited state to fall to a lower state and emit a photon in phase with the original field. Lasers are designed to take advantage of this process.
An atom's properties are mostly described by its electronic configuration. Stimulated emission is reall... | <urn:uuid:5c77ef43-a457-448c-82da-b653f6198b37> | 3.625 | 630 | Knowledge Article | Science & Tech. | 40.616409 |
10 Years of Aqua Satellite’s Incredible Images of Earth From Space
The view of Earth from space has transformed our understanding of, as well as our admiration for, the planet. The data and images collected by Earth-observing satellites have been used in thousands of scientific papers, helped us better respond to natur... | <urn:uuid:fd75ef6e-4f45-4e62-886b-91ead14f7901> | 3.453125 | 252 | Truncated | Science & Tech. | 43.402066 |
Tag: "colors" at biology news
Giant pandas see in color
...that both pandas were able to discriminate between colors
and various shades of gray. The research is publis...ether giant pandas can tell the difference between colors
and shades of gray. In separate tests, the two pandas (Lun Lun the female and Yang Yang the ... | <urn:uuid:f4fa2a60-0487-4a04-bf61-cd9d28d7d3e0> | 2.703125 | 1,526 | Content Listing | Science & Tech. | 48.942423 |
Structural variety and tectonic evolution of strike-slip basins related to the Philippine Fault System, northern Luzon, Philippines
Article first published online: 26 JUL 2010
Copyright 1993 by the American Geophysical Union.
Volume 12, Issue 1, pages 187–203, February 1993
How to Cite
1993), Structural variety and tec... | <urn:uuid:910bdfae-abb3-46b4-a011-31fdba9169a9> | 2.703125 | 536 | Academic Writing | Science & Tech. | 31.357065 |
Melbourne, Australia - October 27, 2009
Comet Caesar, with recorded sightings in 44BC, is the oldest known periodic comet. With Bast's hypothesis of 5 orbits averaging 1025 years, the 44BC passage fits in well with the 2012 end date, and just as importantly the 3114BC start date, of the Mayan Long Count calendar. This ... | <urn:uuid:b6174964-d466-4e94-8a5e-3e1514953599> | 3.59375 | 343 | Personal Blog | Science & Tech. | 49.917696 |
Unicode is a standard that provides a unique number for every character and symbol in the various languages used around the world. It is hardware, development platform and language independant. The current assigned codes are all within the range of a 16-bit integer with the first 256 entries being identical to ISO 8859... | <urn:uuid:7004e052-aa5d-4073-9c30-a323044f87df> | 4.25 | 445 | Knowledge Article | Software Dev. | 50.402331 |
I was pair programming with an experienced Java Developer today and we again came up with the discussion of what goes on a stack and what goes on a heap. Though while coding application logic we are hardly concerned on what goes where but it definitely helps to know as it would help in better understanding of argument ... | <urn:uuid:ebaf4ee5-e369-4c87-825f-bf7730a90e4e> | 3.0625 | 230 | Personal Blog | Software Dev. | 57.959159 |
What Is Nanotechnology? Is Nanotechnology Science Fiction?
Most nano-science is speculative at the moment, given the fact that the theoretical applications of nanotechnology are so far-ranging. That being said, according to the “Project on Emerging Technologies” (which is a partnership of Pew Charitable Trusts and the ... | <urn:uuid:fb545656-85c7-4eaa-a6e3-ecfe3895d19f> | 2.890625 | 1,083 | Personal Blog | Science & Tech. | 23.686912 |
Last Updated: Jan 8th, 2011 - 16:45:13
| The Physics of Teleportation - Jumper
By Cynthia Kirkeby
Feb 12, 2008, 08:26 PST
Lesson Plans for Jumper
Grade Level: 7-12
Subject: Science, Physics,
MPAA Rating: PG-13 for sequences of intense action violence, some language and brief sexuality.
Keywords: Jumper, physics, scienc... | <urn:uuid:af96e447-bfc9-4582-a191-423fa85f889c> | 3.375 | 1,214 | Tutorial | Science & Tech. | 35.025207 |
Changing environmental conditions could put diverse ecosystems, such as rainforests and coral reefs, at greater risk of multiple extinctions. A new study suggests that, rather than protecting ecosystems from collapse, high levels of biodiversity may actually prove risky in a situation such as climate change – where an ... | <urn:uuid:d24fb258-f116-4fe6-9685-85cb9aff4991> | 4.0625 | 683 | Truncated | Science & Tech. | 21.446429 |
Defining a Generator
Building a generator is about defining how to map model concepts to code or other output. In the simplest case, each modeling symbol produces certain fixed code that includes the values entered into the symbol as arguments by the modeler. To go a bit further a generator can also take into account r... | <urn:uuid:e07ef16e-9998-4ab8-addc-9a3001203a65> | 2.78125 | 1,878 | Documentation | Software Dev. | 27.834075 |
“We would like to argue that the most accurate method for transcriptome analysis is sequencing,” notes Kai Lao, Ph.D., principal scientist, genetic systems, Life Technologies. “Recent advances in high-throughput sequencing made it possible to analyze single-cell transcriptomes at high resolution.”
Life Technologies use... | <urn:uuid:41de1d7e-96f0-4c5e-b970-5373b081fdb2> | 2.890625 | 1,261 | Truncated | Science & Tech. | 30.06565 |
[Haskell-beginners] the ($) function (was desugaring an example
john.hartnup at gmail.com
Mon Feb 23 14:21:06 EST 2009
I had exactly the same confusion - not explaining ($) in RWH was major
dropped ball IMO.
> bogusTransfer qty fromBal toBal = do
> fromQty <- atomically $ readTVar fromBal
... is equivalent to:
bogusTra... | <urn:uuid:d4cd2cf1-3524-4188-974f-33c8b7ad2aa3> | 2.84375 | 165 | Comment Section | Software Dev. | 56.28861 |
Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text o... | <urn:uuid:44d1e655-ec09-4667-9903-4d4121c9237e> | 2.703125 | 840 | Content Listing | Science & Tech. | 22.132701 |
About my last question pertaining to the energy of cells
set at 300 millivolts, this is the website I saw it on:
The website says that the energy present around the
membrane of a cell is around 300 millivolts. Anyways, here is my new
How, exactly, does ATP provide energy to a cell?
ATP is the abbreviation of Adenoside-... | <urn:uuid:02b5e741-38a3-468a-a75f-847954971a92> | 3.25 | 592 | Q&A Forum | Science & Tech. | 47.981345 |
hat percentage of integers have Rational Roots? Solvers will recall that a number r is said to be rational if and only if r can be expressed as p / q where p and q are integers. An irrational number cannot be expressed as a ratio of integers. Surely, the most famous is , the ratio of dircumference of a circle to its di... | <urn:uuid:ddfe1e28-24bb-4f85-9d44-f7a3653c0324> | 2.828125 | 599 | Personal Blog | Science & Tech. | 64.114799 |
* Gen. Pl.: 310. 4 Aug 1789
A cactus (plural: cacti, cactuses or cactus) is a member of the plant family Cactaceae. Their distinctive appearance is a result of adaptions to conserve water in dry and/or hot environments. In most species, the stem has evolved to become photosynthetic and succulent, while the leaves have ... | <urn:uuid:8aa71c91-a6b4-4c11-a2c0-788ee6ccf62b> | 3.484375 | 2,468 | Knowledge Article | Science & Tech. | 34.972143 |
Color the picture by clicking on a color swatch at the bottom of the image then click on the image where you want to apply that color. Color off-line by downloading and printing the pdf version.
The global patterns that occur based upon the earth's tilt, rotation and land/sea distribution are factors responsible for ou... | <urn:uuid:e0281731-94ef-4b42-8126-3ecdcc7a549e> | 3.21875 | 199 | Knowledge Article | Science & Tech. | 42.868713 |