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There are numerous small conventions in mathematics, such as often using for an angle or using to indicate the square of . Some of the conventions such as that a superscript 2 means 'squared' are always used, or at least very nearly always used. Some conventions are more temporary.
- We tend to use , , and for angles r... | <urn:uuid:f76c0574-a88f-46ea-9cc7-3b552442ce9d> | 4.625 | 823 | Tutorial | Science & Tech. | 59.693066 | 2,500 |
Vacuum expectation value
|Quantum field theory|
In quantum field theory the vacuum expectation value (also called condensate or simply VEV) of an operator is its average, expected value in the vacuum. The vacuum expectation value of an operator O is usually denoted by . One of the best known examples of an observable p... | <urn:uuid:2cd5024e-3744-4b88-a7b7-5bb7e567484c> | 3.015625 | 407 | Knowledge Article | Science & Tech. | 53.763121 | 2,501 |
When designing Wrapfs, we concentrated on the following aspects:
The first four points are discussed below. Performance is addressed in detail in Section 5.
Without changing a given Vnode interface, we have identified three items that file system developers want to inspect or manipulate: file data, names, and attribute... | <urn:uuid:4d28475c-e388-45b6-b46c-ac097435f7e4> | 2.734375 | 1,922 | Documentation | Software Dev. | 40.365984 | 2,502 |
<programming> A data type composed of multiple elements. An aggregate can be homogeneous (all elements have the same type) e.g. an array, a list in a functional language, a string of characters, a file; or it can be heterogeneous (elements can have different types) e.g. a structure. In most languages aggregates can con... | <urn:uuid:cd86a712-41e0-41d1-8555-228d13c8ef36> | 3.09375 | 130 | Structured Data | Software Dev. | 42.487918 | 2,503 |
The question asks how to convert local coordinates into geocentric coordinates. As an example,
What would be the geocentric coordinates of a point displaced 250 meters west and 250 meters south of -108.619987 degrees longitude, 36.234600 degrees latitude (at sea level)?
(For the reason why only six decimal places are u... | <urn:uuid:f34d6351-86d3-43b2-8ccc-15d9eeac2104> | 3.96875 | 1,731 | Q&A Forum | Science & Tech. | 65.547536 | 2,504 |
Become a fan of h2g2
Earth is the third planet from the Sun, and, as far as we know, where all humans live.
- Mass: 5.9736×1024kg
- Equatorial Radius: 6378.1km
- Mean Density: 5515kg/m3
- Length of Day: 24.0000 hours
- Period of Revolution about Sun: 365.256 days
- Acceleration due to Gravity: 9.81m/s2
- Mean Orbital V... | <urn:uuid:724ce15c-e412-477f-988f-06d9112f3002> | 3.421875 | 347 | Knowledge Article | Science & Tech. | 73.556131 | 2,505 |
For years scientists thought only two planets in our solar system had tectonic plates. But, now, it looks like Mars is joining the club.
There are a few well known warning signs, such as earthquakes in the vicinity of a known volcano. And, of course, smoke rising from a volcano.
Where is the last place you would expect... | <urn:uuid:d320ec08-4190-43aa-bf1c-a5a8d56a612a> | 3.609375 | 270 | Content Listing | Science & Tech. | 61.17047 | 2,506 |
Scientists produce transparent, light-harvesting material
- James E. Rickman
- Communications Office
- (505) 665-9203
Breakthrough could lead to solar-power-generating windows
LOS ALAMOS, New Mexico, NOVEMBER 3, 2010—Scientists at the U.S. Department of Energy's Los Alamos National Laboratory and Brookhaven National La... | <urn:uuid:6f6cfa7b-3694-4cd5-8e36-cecebaf4f69c> | 3.4375 | 955 | News (Org.) | Science & Tech. | 16.187085 | 2,507 |
How will science and technology fare at the Rio+20 summit? Aisling Irwin looks at scientists' demands and assesses their chances.
Is this the last chance for scientists to save the planet?
The UN Conference on Sustainable Development — Rio+20 — enters its final phase of negotiations next week at a summit to be attended... | <urn:uuid:651e28a2-6864-4b67-b6e7-e2f63fb2efad> | 2.984375 | 3,930 | Truncated | Science & Tech. | 21.138648 | 2,508 |
Create reusable content
You can make elements on a screen into user controls that can be used in multiple pages throughout a prototype. For example, you can create a navigation bar, and then make the navigation bar into a user control so that you can reuse the control throughout your prototype.
For more information abo... | <urn:uuid:b845d177-2172-499b-b58d-ab23ae262735> | 2.8125 | 407 | Documentation | Software Dev. | 51.050759 | 2,509 |
An ancient quest for the perfect blue ended in a hot furnace in OSU’s Department of Chemistry — totally by accident.
A blue pigment that is both safe and stable eluded the Egyptians, the Han Dynasty and the Mayans. The French developed cobalt blue in the 1800s, but it contains carcinogens. Prussian blue releases cyanid... | <urn:uuid:226e2445-09ce-4c14-b241-cec740c07311> | 3.703125 | 228 | Knowledge Article | Science & Tech. | 38.415039 | 2,510 |
(PhysOrg.com) -- Engineers at the University of California at San Diego put a single-story house to the test on January 26 via a series of strong simulated earthquake shakes. The first jolt to the wood-stud structure with brick veneer measured a 6.6 magnitude, with the final one coming in at 7.2.
Wood stud frames with ... | <urn:uuid:eac1eaf5-341c-4ea9-8728-ec8ef71bc967> | 2.734375 | 735 | News Article | Science & Tech. | 26.556663 | 2,511 |
This is a clear and concise treatise on phase transition, written by Leo Kadanoff, one of the leading figures today in condensed matter physics. Even if you don't understand the mathematics, the written description of phase transition is very well presented, so I highly recommend this for everyone to read.
Abstract: Th... | <urn:uuid:0ccff45f-bf53-4ad6-a679-cbd515f50430> | 2.921875 | 372 | Personal Blog | Science & Tech. | 28.436696 | 2,512 |
What is Planetary Protection?
Planetary protection is the term given to the practice of protecting solar system bodies (i.e., planets, moons, comets, and asteroids) from contamination by Earth life, and protecting Earth from possible life forms that may be returned from other solar system bodies. Planetary protection i... | <urn:uuid:ab1d9536-046e-42d8-aee0-c21badf37f85> | 3.65625 | 1,016 | Knowledge Article | Science & Tech. | 10.28183 | 2,513 |
Do you know what's good for you: the next microscope
"Mathematics is biology's next microscope, only better." That's what the scientist Joel E Cohen once said of the power of mathematics to revolutionise biology and the biomedical sciences. And he was right. Maths enables scientists to understand complex organisms and ... | <urn:uuid:dae28e7f-d50c-4726-8cf4-51b5e1316c99> | 3.265625 | 289 | Truncated | Science & Tech. | 30.867088 | 2,514 |
Let’s see how much we know about it.
Note the Definition, ‘appears to attract’ – We are not sure.
Einstein’s Views -’Theory of General Relativity‘ as applied to Gravity.
Space and Time , Spacetime condition Gravity.
“General relativity, or the general theory of relativity, is the geometric theory of gravitation publish... | <urn:uuid:2195b4ea-3b90-4842-b377-6dfae66d9f6c> | 3.640625 | 1,237 | Personal Blog | Science & Tech. | 40.665737 | 2,515 |
Explanation of Characteristics of Fluids by Ron Kurtus - Succeed in Understanding Physics. Key words: Physical Science, states of matter, solid, gas, liquid, plasma, shape, container, gravity, sphere, spreading, pour, flow, School for Champions. Copyright © Restrictions
Characteristics of Fluids
by Ron Kurtus (revised ... | <urn:uuid:b04d95f3-6fb6-4aaa-b4a3-010dc6dab246> | 4.28125 | 1,374 | Truncated | Science & Tech. | 55.848482 | 2,516 |
On July 5, 1996, the most famous sheep in modern history was born. Ian Wilmut and a group of Scottish scientists announced that they had successfully cloned a sheep named Dolly.
If you stood Dolly beside a "naturally" conceived sheep, you wouldn't notice any differences between the two. In fact, to pinpoint the only ma... | <urn:uuid:0ceebd2d-a830-4224-bff9-32a888dd3abc> | 3.5 | 371 | Knowledge Article | Science & Tech. | 47.759885 | 2,517 |
[Mystery bird] Phainopepla, Phainopepla nitens, photographed in Arizona. [I will identify this bird for you tomorrow]
Image: Richard Ditch, 2006 [larger view].
Date Time Original: 2006:05:07 07:33:04
Exposure Time: 1/200
Please name at least one field mark that supports your identification.
Rick Wright, Managing Direct... | <urn:uuid:dbfcf85b-f0bd-4e5a-beec-3693af486290> | 2.53125 | 296 | Personal Blog | Science & Tech. | 47.792 | 2,518 |
SETI researcher proposes we look for signs of past alien life on Earth or in our solar system.
Any intelligent extraterrestrial life that exists probably won't announce itself by blowing up the White House, or win over the hearts of children as a lovable alien with a glowing finger. Many scientists simply hope to find ... | <urn:uuid:7c93d889-2449-4ea5-b9f5-6dab63364f24> | 3.046875 | 527 | News Article | Science & Tech. | 40.629559 | 2,519 |
TrimastixAlastair Simpson and Vladimir Hampl
This tree diagram shows the relationships between several groups of organisms.
The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor ... | <urn:uuid:ab973b74-8356-46d6-bd58-d50271624529> | 3.453125 | 2,160 | Knowledge Article | Science & Tech. | 51.544745 | 2,520 |
By Jessica Kowalik, George Washington University
From deep-sea hydrothermal vents to our own gastrointestinal biomes, bacteria that convert hydrogen to energy are a crucial and fascinating component of microbial ecosystems. Their hydrogen consumption may hold the key to explaining why certain animals are able to flouri... | <urn:uuid:66da3d10-b903-4c52-89f3-a388e5730bea> | 3.890625 | 1,620 | Academic Writing | Science & Tech. | 21.213589 | 2,521 |
Pacific Coastal & Marine Science Center
Bedform Sedimentology Site: “Bedforms and Cross-Bedding in Animation”
FIG. 42b. Structures formed by bedforms with along-crest- migrating in-phase sinuosities. Fig. 42a (A) Rate of along-crest migration of sinuosities is equal to the rate of lateral migration of the main bedform.... | <urn:uuid:f3c41da6-d394-419a-91af-d21111eb3509> | 3.6875 | 274 | Knowledge Article | Science & Tech. | 29.46 | 2,522 |
People seem to have very poor intuition about probability. It can take a lot of training to learn how to calculate probabilities correctly.
Massimo Piattelli-Palmarini. Inevitable Illusions. 1994
You are on a Game Show, and there are three boxes in front of you. Your host, Monty Hall, tells you that one of the boxes co... | <urn:uuid:94191d8f-8f89-48db-98de-a10222567698> | 2.640625 | 790 | Nonfiction Writing | Science & Tech. | 61.536962 | 2,523 |
Science Fair Project Encyclopedia
Intuitively, a space is complete if it "doesn't have any holes", if there aren't any "points missing". For instance, the rational numbers are not complete, because √2 is "missing" even though you can construct a Cauchy sequence of rational numbers that converge to it. (See the examples... | <urn:uuid:91351a8e-8f44-4fca-9450-6a233a2a604c> | 3.25 | 1,244 | Knowledge Article | Science & Tech. | 47.902841 | 2,524 |
Microrockets Fizz Along
Tiny devices push themselves forward on a stream of hydrogen bubbles
In an acidic solution, a microrocket zips around at speeds of up to 1,050 micrometers a second—not bad for something only about 8 micrometers long, too small to be seen by the human eye. The minuscule cone-shaped devices, creat... | <urn:uuid:85b834e0-4e9b-457d-9906-ff015209e2ac> | 4.15625 | 954 | News Article | Science & Tech. | 39.611023 | 2,525 |
Aside from the spectacular light shows they produce, substorms are of great scientific interest. The processes that are thought to be at work in them are also thought to occur in the solar corona and other more distant and exotic objects in the cosmos. The substorm provides us with the only place in nature where we can... | <urn:uuid:6bd1384a-3f31-4455-b475-2b597de55182> | 2.9375 | 158 | About (Org.) | Science & Tech. | 28.180043 | 2,526 |
Comet PANSTARRS to glow in evening twilight
Comet PANSTARRS, the brightest such object in six years, will stand out this March.
January 24, 2013
A dazzling comet can ignite a viewer’s passion better than almost any other celestial object. Those flames could burn bright this month for seasoned observers and novices alik... | <urn:uuid:1b11de2a-abcd-4e8e-9fe1-6236c0a636f0> | 2.953125 | 936 | News Article | Science & Tech. | 51.548908 | 2,527 |
By Nick Gilbert
A study conducted by Element Six, a specialist in synthetic diamond supermaterials, along with scientists from the Departments of Chemistry and Physics at the University of Warwick, has revealed that boron-doped synthetic diamond materials can be suitable for a new generation of electrochemical applicat... | <urn:uuid:08f60681-c089-45ca-accd-609c3fd15cf8> | 2.875 | 343 | News Article | Science & Tech. | -0.762162 | 2,528 |
As I write this, the engine room is carefully adjusting the ship's ballast. This is an interesting physics problem for all you scholars out there. As we burn fuel, we transform the heavy liquid into a gas exhaust that leaves the confines of the ship. Therefore, we're getting lighter.
As we get lighter, we sit higher in... | <urn:uuid:d2745840-ee98-427e-88ef-f8433a579c32> | 2.875 | 981 | Audio Transcript | Science & Tech. | 60.138815 | 2,529 |
DIVERSITY & ENDEMISM
Although research into the flora of the Horn of Africa is still ongoing, the best possible estimates are that there are about 5,000 species of vascular plants in the region, just over half of which – about 2,750 species – are endemic. There are strong concentrations of endemic species in northern S... | <urn:uuid:e9832b38-80c2-4a88-accb-36480d2dbf17> | 3.359375 | 1,614 | Knowledge Article | Science & Tech. | 25.314095 | 2,530 |
Over the past decade, Web applications have evolved from static HTML pages, to Dynamic HTML pages, to applets and Flash, and, finally, to Ajax technologies. Ajax systems will play an ever increasingly important role in future as the proliferation of complex Web Applications into our daily lives continues. In general, t... | <urn:uuid:ef68a3b2-f20b-40e6-aa56-ee112439d1ef> | 2.671875 | 1,092 | Knowledge Article | Software Dev. | 21.063135 | 2,531 |
This tutorial series will run for five consecutive weeks. In this installment, Go expert Mark Summerfield explains how to set up Go, and then he provides two examples of Go programs that are explained in depth. The programs provide a partial overview of Go's key features and some of its key packages. The following week... | <urn:uuid:c32a6fff-7288-4c6e-b13e-1269b631523d> | 3.046875 | 1,379 | Documentation | Software Dev. | 54.521296 | 2,532 |
Trees are very important and necessary for existence of life on this planet. It’s impossible to believe life without trees, trees play important role in our very dependable food cycle.
Our existing forests and trees we plant in our life work inline to make this planet better place to live and flourish, thus saving and ... | <urn:uuid:8a6f55e8-46db-421c-8215-81f5ef4f45cf> | 3.359375 | 499 | Knowledge Article | Science & Tech. | 46.763455 | 2,533 |
The form element contains all the component elements of an HTML online form. Forms are a way of capturing user input whether they be personal details, user preferences or an order for goods or services. This input is entered into the form and then the information is sent, usually over the Internet, for whatever action ... | <urn:uuid:5a83c702-6b6a-4399-8886-6b27c00ec1c7> | 3.625 | 471 | Documentation | Software Dev. | 46.029767 | 2,534 |
KANSAS CITY, Missouri - The Lezak's Recurring Cycle (LRC) is a theory developed by Gary Lezak. Gary noticed back in the 1980s that storm systems seemed to have similar characteristics unique to that year.
Quite simply a storm in February looked very similar to one that had occurred earlier in that season, say in Decemb... | <urn:uuid:6beed086-221e-48a2-aead-948fb989b333> | 2.546875 | 387 | News Article | Science & Tech. | 56.155694 | 2,535 |
Swirls are bright, often splashy-looking areas that are typically associated with strong magentic anomalies. Reiner Gamma is the most familiar swirl on the Moon. There are only a few known swirls but the number is now increased by one with the recognition that the bright rubbly spot (red circle) on the rim of Descartes... | <urn:uuid:1aec4a45-6b05-4aed-b8a3-11b467233c87> | 3.34375 | 494 | Knowledge Article | Science & Tech. | 50.338664 | 2,536 |
...with web-based podcatchers:
...with something else:
View RSS Feed
Get more info on other podcatchers:
Click for more "Microbes After Hours" videos
Puerto Rico is widely known as the "La Isla del Encanto," which translated means "The Island of Enchantment." And while its beaches, tropical rain forest, and biolumescen... | <urn:uuid:925a6480-ebe7-43e8-950e-3efcd90c5b13> | 2.84375 | 435 | Truncated | Science & Tech. | 39.189707 | 2,537 |
This study deals with preparation of substrates suitable for surface-enhanced Raman spectroscopy (SERS) applications by sputtering deposition of gold layer on the polytetrafluorethylene (PTFE) foil. Time of sputtering was investigated with respect to the surface properties. The ability of PTFE-Au substrates to enhance ... | <urn:uuid:bfda52f2-e311-481c-82ab-037f002ffb16> | 2.765625 | 3,406 | Academic Writing | Science & Tech. | 48.110748 | 2,538 |
2013 Scientist Registration
Photograph by Karine Aigner
A BioBlitz is a unique combination of taxonomic inventory, public outreach, and science education. At its core, the BioBlitz is a species inventory in which teams of volunteers, each led by an expert scientist, find, identify, and map as many species as possible w... | <urn:uuid:e4b5cca9-a31d-42ee-ad68-048ebff7a776> | 3.421875 | 390 | News (Org.) | Science & Tech. | 30.066053 | 2,539 |
If 4 million cars were taken off the road in a single year, stopping 9 billion kilograms of carbon dioxide being discharged, most environmentalists would whoop with joy. But what if the same saving came from planting genetically modified crops?
This is the claim of an annual audit of GM crops by the International Servi... | <urn:uuid:9270afc8-64c6-45fa-9e94-2a05f17d847a> | 3.1875 | 211 | Truncated | Science & Tech. | 52.839662 | 2,540 |
Stopping the Earth's rotation
Name: Adam L Chorak and Janette L Gubala
What would happen if the Earth's rotation stopped?
The biggest changes would be the climate. One side would be very hot and
the other very cool and dark. There would be lots of other related changes.
There are very few ways that we could slow down t... | <urn:uuid:7fde5d86-e972-488b-a23a-d8da96a359a7> | 3.296875 | 225 | Comment Section | Science & Tech. | 65.232098 | 2,541 |
The Echinoderm Portal
Five groups are counted among Recent echinoderms, feather stars and sea lilies (Crinoidea), seastars (Asteroidea), brittle and basket stars (Ophiuroidea), sea urchins (Echinoidea) and sea cucumbers (Holothuroidea). Additional about 15 groups have gone extinct during the long history of evolution.
... | <urn:uuid:05f5c112-3785-4350-ba6c-e6d6302f5df1> | 3.5 | 200 | Knowledge Article | Science & Tech. | 33.200741 | 2,542 |
Zend Framework 101: Zend_Log
Creating Your First Logger
To begin, I'll show you how to create a basic file-system logger. To achieve this we must instantiate the
Zend_Log class, then add a writer to this object. We will use a writer that writes log messages to the file system.
The class we use to write log messages to ... | <urn:uuid:a3777f98-9e49-4e8b-9d72-c23cecaebf70> | 2.625 | 348 | Documentation | Software Dev. | 68.132292 | 2,543 |
There are many things we’ve come to expect from our computer printers: photos, letters, greeting cards, maybe even glowing wallpaper someday. But muscle and bone? You wouldn’t have gone there until this week, when scientists at Carnegie Mellon announced they have developed a printer that outputs in “bio-ink”—a format t... | <urn:uuid:b94ef1ac-55b4-4f64-aab3-bbbcf7cdb251> | 2.765625 | 431 | News Article | Science & Tech. | 51.401963 | 2,544 |
Professor Rodríguez-Iturbe discusses new fish diversity model
Posted May 7, 2008; 12:55 p.m.
This interview is based on a paper published in the journal Nature on May 8, 2008. Read more
Video Closed Captions
I am a hydrologist, which basically means that I deal with the movement
of water in landscapes.
The dynamics of ... | <urn:uuid:c5b97874-0143-4075-bec5-b72e1c165b94> | 2.6875 | 427 | Audio Transcript | Science & Tech. | 44.210354 | 2,545 |
Anales del Instituto de la Patagonia
versão On-line ISSN 0718-686X
CARDENAS M, Carlos; JOHNSON G, Erling e CARVALLO B, Rubén. Surface an subglacier topography near to the O'Higgins Base Station at north of the Antarctic Peninsula. Anales Instituto Patagonia (Chile) [online]. 2011, vol.39, n.2, pp. 97-101. ISSN 0718-686... | <urn:uuid:65e0b878-713f-453c-841c-b0d79e14578c> | 2.859375 | 311 | Knowledge Article | Science & Tech. | 55.694461 | 2,546 |
April 30, 2009: A NASA spacecraft gliding over the surface of Mercury has revealed that the planet's atmosphere, magnetosphere, and its geological past display greater levels of activity than scientists first suspected. The probe also discovered a large impact basin named "Rembrandt" measuring about 430 miles in diamet... | <urn:uuid:7ad896bb-abda-4353-b352-11d78bfad205> | 3.71875 | 1,355 | News (Org.) | Science & Tech. | 32.243789 | 2,547 |
Web edition: April 26, 2004
Print edition: May 1, 2004; Vol.165 #18 (p. 287)
I know some people who carefully shield their bodies from the sun with sunscreen and clothing, and their skin is extremely pale. But if tanning acts as a protector ("Sunny Solution: Lotion speeds DNA repair, protects mice from skin cancer," SN... | <urn:uuid:c1a1a422-09a6-4622-a89a-ebf2bd2873b7> | 3.03125 | 573 | Comment Section | Science & Tech. | 77.069679 | 2,548 |
Summary: For the past 4 billion years, the chemistry of the Earth's surface, where all life exists, has changed remarkably. Historically, these changes have occurred slowly enough to allow life to adapt and evolve. In more recent times, the chemistry of the Earth is being altered at a staggering rate, fueled by industr... | <urn:uuid:5d6457bf-106e-46f8-b7bc-49cf61d6b4dd> | 3.3125 | 270 | Product Page | Science & Tech. | 32.9575 | 2,549 |
SAN MARCOS — Volunteers from across Texas will participate in the fourth annual statewide water sampling initiative to be held in conjunction with Earth Day 2003 on April 22.
Texas Watch, a volunteer environmental monitoring program supported by Southwest Texas State University, the Texas Commission on Environmental Qu... | <urn:uuid:8360bf6a-4181-4431-a2ef-26f9faaf29dd> | 2.65625 | 403 | News (Org.) | Science & Tech. | 26.285425 | 2,550 |
Narrator: This is Science Today. Recent images of dust storms on Mars are helping astronomers study its changing surface and weather conditions and prepare for NASA's mission to send rovers to explore the planet's surface in 2004. Meanwhile, biochemist Mark Thiemens of the University of California, San Diego has develo... | <urn:uuid:4a2be97f-13b9-42b2-a73b-7cab01f0e7e3> | 3.8125 | 237 | Audio Transcript | Science & Tech. | 35.58345 | 2,551 |
BALTIMORE, June 14 (UPI) -- NASA says the Hubble Space Telescope has captured a chance alignment between two galaxies that mimics what a cosmic collision would look like.
While the two galaxies look as if they are colliding, they are actually separated by tens of millions of light-years, or about 10 times the distance ... | <urn:uuid:63e4e9ee-bb9f-4cb4-b00b-18db58a2e903> | 3.40625 | 226 | News Article | Science & Tech. | 23.057 | 2,552 |
The spruces can be recognized
as a genus by the sharp pointed needles, nearly square in
cross-section (not strongly flattened) and attached to the
twigs by sterigmata.
The terminal branches of mature trees of Picea abies
often hang down giving them a distinctive appearance which
together with the very large cones make ... | <urn:uuid:9419f22a-c390-4998-acb3-caeec751afc7> | 2.875 | 139 | Knowledge Article | Science & Tech. | 34.795903 | 2,553 |
Promethium: geological information
It appears that there is no known Pm existing in the earth's crust other than in very small quantities in uranium ores where it is present as a uranium decay product.
Abundances of promethium in various environments
In this table of abundances, values are given in units of ppb (parts ... | <urn:uuid:6e92b604-e1c7-4bb4-9fd0-a185f54b857c> | 3.703125 | 259 | Knowledge Article | Science & Tech. | 38.495962 | 2,554 |
Radiation can damage DNA molecules in three ways: by causing a single strand break, a break in both strands, or a chemical change or mutation. A single strand break can often be repaired by the cell. The other two types of damage usually cannot be repaired.
Click on image for full size
Can living cells repair damage fr... | <urn:uuid:1e1562a7-d27f-49bd-81d6-bdceb9d265ba> | 3.4375 | 604 | Knowledge Article | Science & Tech. | 50.690769 | 2,555 |
Thermohaline Circulation: The Global Ocean Conveyor
The world has several oceans, the Pacific, the Atlantic, the Indian, the Arctic, and the Southern Ocean. While we have different names for them, they are not really separate. There are not walls between them. Water is able to move freely between oceans. They are all c... | <urn:uuid:d154ff21-d8cc-4832-970a-8cea60ff2dd5> | 3.859375 | 572 | Knowledge Article | Science & Tech. | 47.810943 | 2,556 |
Bison roaming on mixed grass prairie - a type of grassland - at Wind Cave National Park (U.S.)
Click on image for full size
National Park Service
Do you know what grassland looks like? You're right, it looks like fields of grass! But there
are many different types of grass. Some look a lot different than the grass in y... | <urn:uuid:56f181b7-55c0-4d42-9915-902fa4586faa> | 2.921875 | 503 | Content Listing | Science & Tech. | 69.386462 | 2,557 |
A photo of the flight crew taken earlier this month. The crew is standing in front of the Shuttle Discovery (with its new lightweight external tank). From left to right, they are Pilot Dominic Gorie; Mission Specialists Franklin Chang-Diaz, Ph.D.; Wendy B. Lawrence and Janet Kavandi, Ph.D.; Mission Commander Charles Pr... | <urn:uuid:85614033-dc36-4631-8e4c-67cb61bd5a44> | 2.765625 | 639 | Content Listing | Science & Tech. | 64.212075 | 2,558 |
Presented in Association with the Western New Mexico University Department
of Natural Sciences
Simmondsiaceae (Jojoba Family)
The Simmondsiaceae are represented by a single genus and species, Simmondsia chinensis, commonly known as Jojoba. Simmondsia chinensis is usually thought of as a Sonoran Desert species, and is a... | <urn:uuid:2ac46bf7-226c-40b4-8734-525d07fd147a> | 3.3125 | 104 | Knowledge Article | Science & Tech. | 17.572283 | 2,559 |
Study Co-authored by Robert Gegear Provides New Insight into the Sun Compass That Helps the Monarch Butterfly Navigate
Published in Nature Communications, the study, conducted at UMass Medical, looks at the role of clocks in the insect's antennae.
Published in the prestigious journal Nature Communications, the study, b... | <urn:uuid:408c1042-7766-4e0e-acda-61299f076cab> | 3.65625 | 848 | News (Org.) | Science & Tech. | 26.269412 | 2,560 |
General relativity is a theory which describes space, time and the gravitational field in terms of a Lorentzian metric . A complete understanding of the gravitational field requires an understanding of the matter sources which generate it. In the Einstein equations, , the left hand side depends only on and is a feature... | <urn:uuid:7a8fe757-e6d6-4a38-bbe7-6984253d3f2f> | 2.84375 | 1,064 | Personal Blog | Science & Tech. | 44.16052 | 2,561 |
Mathematics-filter: If there are seven funds with various charges, how can I work out the allocation to these funds of a fixed amount so that the weighted mean charge is below a certain level and the allocations are of similar sizes? [more inside]
posted by djgh
on Dec 31, 2012 -
Can you cite any examples where a techn... | <urn:uuid:bff01b08-c9bc-48cd-85a3-46142856ef21> | 2.640625 | 532 | Comment Section | Science & Tech. | 52.104342 | 2,562 |
You can estimate your personal carbon footprint, or the carbon footprint for your household, at several Web sites.
Your answer will depend on the size of your home, how much you drive, whether you fly frequently and many other factors.
The answer can also depend (and this won't surprise the parents of teenagers) on how... | <urn:uuid:817dc7ec-6fef-4be8-9046-e8fccf5962b1> | 2.828125 | 246 | Tutorial | Science & Tech. | 53.207653 | 2,563 |
WHAT IS THE DIFFERENCE BETWEEN CLIMATE CHANGE AND GLOBAL WARMING?
Climate change is the shift in long-term, global weather patterns due to human action; it’s not exclusive to warming or cooling.
Climate change includes any change resulting from different factors, like deforestation or an increase in greenhouse gases. G... | <urn:uuid:b513f196-4f91-41de-aa53-24d58e3356b7> | 3.515625 | 702 | Knowledge Article | Science & Tech. | 27.254591 | 2,564 |
This module provides functions to manipulate packages:
Extend the search path for the modules which comprise a package. Intended use is to place the following code in a package’s __init__.py:
from pkgutil import extend_path __path__ = extend_path(__path__, __name__)
This will add to the package’s __path__ all subdirect... | <urn:uuid:11f44825-4793-4296-b0a2-770a8ee7b1ae> | 2.65625 | 516 | Documentation | Software Dev. | 56.154814 | 2,565 |
2008-07-30 03:10:51 GMT 2008-07-30 11:10:51 (Beijing Time) SINA.com
This image shows pollen tubes extending from grains of pollen in the rare vine Austrobaileya. University of Tennessee, Knoxville, researcher Joe Williams found that the tubes' ability to grow quickly played a major role in the evolution of the large va... | <urn:uuid:4751d3c7-8b00-45c9-a5f9-18ac92f804e3> | 4.03125 | 741 | News Article | Science & Tech. | 40.097588 | 2,566 |
Visual C++ Network: When does 'send()' return?
Q: When does 'send()' return?
A: As being indicated in the FAQ "Does one call to 'send()' result in one call to 'recv()'?" , there are some specialties about the 'send()' function as well which need to be understood.
If no error has occurred, 'send()' will return the numbe... | <urn:uuid:38f4394b-81e3-4374-9a83-8876b5cb0b5b> | 3.078125 | 553 | Q&A Forum | Software Dev. | 63.212325 | 2,567 |
You may also attempt to solve it yourself as a mathematical exercise. Using your own senses, you can see that the illustration is a 7x7 grid with three red squares on it it the positions (3,4), (5,2), and (5,5) depending on how you define your coordinate system. If this drawing were on the $xy$ plane and your camera is... | <urn:uuid:94c7e4c9-61df-45e8-97d2-7d68de0e2d7d> | 3 | 302 | Tutorial | Science & Tech. | 48.20671 | 2,568 |
A media type is a way to describe the format of a media stream. In Media Foundation, media types are represented by the IMFMediaType interface. Applications use media types to discover the format of a media file or media stream. Objects in the Media Foundation pipeline use media types to negotiate the formats they will... | <urn:uuid:6c659310-cdb5-4a1d-afbb-ad94259eecd9> | 3.03125 | 239 | Documentation | Software Dev. | 36.569892 | 2,569 |
Why geomagnetic storms affect telegraphs, telephones, power grids and piplines
The Space Environment Center website has information on solar conditions and the effects of the solar wind, under the headings of Geomagnetic Storms, Solar Radiation and Radio Blackouts. A surprising number of things are affected by solar we... | <urn:uuid:80cd1ad0-e0f7-4003-bbae-ee1c96980fbf> | 3.15625 | 1,534 | Personal Blog | Science & Tech. | 42.193 | 2,570 |
By Irene Klotz
Famed physicist Stephen Hawking didn't need his voice synthesizer to express how he felt about experiencing weightlessness in a zero-gravity simulating aeroplane.
"He was grinning the entire time," said Peter Diamandis co-founder of Zero Gravity Corp, which operates the plane Hawking flew aboard.
"It was... | <urn:uuid:5eca964e-ab69-4f6a-ba2b-669df2c11037> | 2.890625 | 495 | News Article | Science & Tech. | 42.860588 | 2,571 |
for National Geographic News
At a glance, it is nearly impossible to identify an individual penguin in a colony of several thousand. That's a serious problem for researchers who want to identify and track individual birds as part of their efforts to protect them.
To overcome the problem, many researchers attach stainle... | <urn:uuid:63a0de51-a1d7-40fe-8cf6-8661ae44fdec> | 3.640625 | 451 | News Article | Science & Tech. | 41.785045 | 2,572 |
At a toasty 3,700 degrees Fahrenheit, the planet is hot enough to liquefy steel. And there’s not much relief from the scorching heat: Researchers at MIT and other institutions say the planet may lack reflective surfaces such as ice caps, instead absorbing most of the heat from its parent star — much as Earth’s dark oce... | <urn:uuid:b5cf01d0-6106-4b14-861c-de6667a2f4bb> | 2.875 | 142 | Truncated | Science & Tech. | 53.835613 | 2,573 |
How Corals Succumb to Sedimentation
Weber, M., de Beer, D., Lott, C., Polerecky, L., Kohls, K. Abed, R.M.M., Ferdelman, T.G. and Fabricius, K.E. 2012. Mechanisms of damage to corals exposed to sedimentation. Proceedings of the National Academy of Sciences USA 109: 10.1073/pnas.1100715109.
In an effort to find the true ... | <urn:uuid:79b3557b-3571-4783-b10d-90b6c22fd394> | 3.1875 | 616 | Academic Writing | Science & Tech. | 50.047845 | 2,574 |
One thing that often confuses new users to the Unix / Linux shell, is how to do (even very simple) maths. In most languages,
x = x + 1 (or even
x++) does exactly what you would expect. The Unix shell is different, however. It doesn’t have any built-in mathematical operators for variables. It can do comparisons, but mat... | <urn:uuid:83df7ef4-ae4a-47ac-9022-0591902c0253> | 3.421875 | 1,194 | Personal Blog | Software Dev. | 67.199412 | 2,575 |
NORMAN — Editor, The Transcript:
John Baugher is correct when he writes, “Global warming is happening” (The Norman Transcript, Sept 25, 2012), but a simpler explanation may be more understandable.
Greenhouse gases of importance in Earth’s atmosphere include carbon dioxide. Increased burning of fossil fuels by humans, o... | <urn:uuid:155cf31c-afd5-4a55-9bef-0a8461611539> | 3.65625 | 249 | Audio Transcript | Science & Tech. | 33.485867 | 2,576 |
This article by Alex Goodwin, age 18 of Madras College, St Andrews
describes how to find the sum of 1 + 22 + 333 + 4444 + ... to n
If a number N is expressed in binary by using only 'ones,' what can
you say about its square (in binary)?
What is the sum of: 6 + 66 + 666 + 6666 ............+ 666666666...6
where there are... | <urn:uuid:affdc18f-9a11-4272-8474-251a752b2ef6> | 2.6875 | 523 | Content Listing | Science & Tech. | 70.648475 | 2,577 |
- Beyond productivity- Effects of extreme weather events on ecosystem processes and biotic interactions (2012)
- Under global climate change, extreme weather events, such as heat waves, drought or heavy rain spells, are projected to increase in magnitude and frequency. As these may affect vegetation and ecosystems more... | <urn:uuid:b333c8bc-efd2-4785-9c39-d7accb2e3118> | 3.328125 | 876 | Academic Writing | Science & Tech. | 6.560333 | 2,578 |
When stars are more massive than about 8 times the Sun, they end their lives in a spectacular explosion called a supernova.
The outer layers of the star are hurtled out into space at thousands of miles an hour, leaving a debris field of gas and dust. Where the star once was located, a small, incredibly dense object cal... | <urn:uuid:1797442c-6d4a-4dc8-be2d-e94524ddc46d> | 4.34375 | 369 | News Article | Science & Tech. | 58.067564 | 2,579 |
June 6, 2011 - The tropics and much of the Northern Hemisphere are likely to experience an irreversible rise in summer temperatures within the next 20 to 60 years if atmospheric greenhouse gas concentrations continue to increase, according to a new climate study by Stanford University scientists. The results will be pu... | <urn:uuid:a46c6e9c-6bb9-43e6-9101-80c4621757a1> | 3.78125 | 777 | News Article | Science & Tech. | 20.153889 | 2,580 |
Ever wonder how much daylight you can gain or lose just by getting in your car and driving either West or East?
Here’s how to figure it out. The Earth’s circumference is about 25,000 miles (40,000 km) at the equator. So if you start out at sunrise and drive 1,000 miles (1,600 km) Westward during the daylight hours, you... | <urn:uuid:0de921e0-3290-404f-a63c-311c02f2b928> | 3.21875 | 606 | Personal Blog | Science & Tech. | 88.52125 | 2,581 |
Berkeley Lab Physicist Challenges Speed of Gravity Claim
18 Jun 2003
(Source: Lawrence Berkeley National Laboratory)
Public Information Department
Lawrence Berkeley National Laboratory
Lynn Yarris, (510) 486-5375, email@example.com
BERKELEY, CA -- Albert Einstein may have been right that gravity travels at the same spe... | <urn:uuid:a00a2c12-9afb-4fa3-8d22-722be5b150f3> | 3.375 | 996 | News (Org.) | Science & Tech. | 33.530694 | 2,582 |
Bat man is a science hero
A bat scientist who left academia 14 years ago to establish his own research station has had his efforts recognised by the scientific establishment.
In 1988 Dr Spencer left a tenured position at the University of Wollongong to establish a tropical research station in the rainforest of Cape Tri... | <urn:uuid:60def203-a661-4f30-a492-c6c7ebc455f0> | 2.828125 | 299 | News Article | Science & Tech. | 34.207537 | 2,583 |
Jellyfish threaten to 'dominate' oceans
Giant jelly fish are taking over parts of the world's oceans due to overfishing and other human activities, say researchers.
"We need to take management action to avert the marine systems of the world flipping over to being jellyfish dominated," says Richardson, who is also a mar... | <urn:uuid:fd4bdb2b-1936-463f-9953-ce05b9e81c26> | 3.203125 | 653 | News Article | Science & Tech. | 37.795738 | 2,584 |
Science Fair Project Encyclopedia
In mathematics, a monomial is a particular kind of polynomial, having just one term. Given a natural number n and a variable x, the power function defined by the rule f(x)=xn is therefore a monomial. Given several unknown variables (say, x, y, z) and corresponding natural number expone... | <urn:uuid:5726de85-a2ca-467b-8ea8-83f038facf26> | 3.921875 | 444 | Knowledge Article | Science & Tech. | 53.082276 | 2,585 |
The SKA observes on a wide range of frequencies. For frequencies lower than 1 GHz, the engineers at ASTRON have developed new technology: large numbers of immobile aperture arrays. ASTRON is coordinator of a European consortium that developed this technology on a large scale. The goal is to show that this technology is... | <urn:uuid:48e6bb36-906e-4e7c-bf5f-5ffefa133ab6> | 3.734375 | 630 | News (Org.) | Science & Tech. | 42.342758 | 2,586 |
Discussion of everything related to the Theory of Evolution.
How have emerged and have become sensible ones membrane-ids, which for many billions of years ago, have built a peptide-nucleic super-technology - is an open question. But how do these membranoidy appeared on Earth - we can explore ...
http://translate.google... | <urn:uuid:77cbb291-4b04-44db-89ee-8f164c96f15e> | 3.4375 | 4,362 | Comment Section | Science & Tech. | 45.951386 | 2,587 |
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Art Meets Science: The Bright Beneath
National Museum of Natural History, December 1, 2011
Bioluminescence, the ability of certain organisms to produce light—including some bacteria and fungi, fireflies, glowworms and many types of fish—was the subject of a fascinating and innovative exhibit at the National Museum of N... | <urn:uuid:4b35e468-c132-499a-972a-98e4d75b9a16> | 2.875 | 1,217 | Content Listing | Science & Tech. | 25.386612 | 2,589 |
quote object => object
Arguments and Values:
object---an object; not evaluated.
The quote special operator just returns object.
The consequences are undefined if literal objects (including quoted objects) are destructively modified.
(setq a 1) => 1 (quote (setq a 3)) => (SETQ A 3) a => 1 'a => A ''a => (QUOTE A) '''a =... | <urn:uuid:724d8ca1-2cd6-4ca6-bffd-2078f0d84949> | 2.5625 | 365 | Documentation | Software Dev. | 70.676872 | 2,590 |
We recently wrote about how hydrogen production is a costly endeavor
for our water supply, as well as the electric gird, effectively making traditional methods of manufacturing a near-impossibility. But Bruce E. Logan, professor of enivronmental engineering at Penn State, has developed a technique that could change tha... | <urn:uuid:33ebe09f-28ac-4fc2-a473-b3bf6ffaf5dd> | 3.828125 | 346 | Knowledge Article | Science & Tech. | 26.003682 | 2,591 |
The spin of a molecule (orange) changes and deforms the nanotube (black) mounted between two electrodes (gold).
(Figure: C. Grupe/KIT)
Carbon nanotubes and magnetic molecules are considered building blocks of future nanoelectronic systems. Their electric and mechanical properties play an important role. Researchers of ... | <urn:uuid:75e3456e-4daf-49fc-8c91-fd04a1770b61> | 3.53125 | 447 | Academic Writing | Science & Tech. | 29.456291 | 2,592 |
The weird world of quantum mechanics describes the strange, often contradictory, behaviour of small inanimate objects such as atoms. Researchers have now started looking for ways to detect quantum properties in more complex and larger entities, possibly even living organisms.
A German-Spanish research group, split betw... | <urn:uuid:d8a0355d-9386-4697-9a1f-b2ec979415d1> | 3.390625 | 610 | News Article | Science & Tech. | 27.414067 | 2,593 |
.NET offers many useful features like Base Class Library [BCL], Just in Time compiler [JIT], intermediate code known as MSIL, code access security and Garbage Collector aka GC. GC is responsible for memory management and is credited with the success of .NET platform as well as some really strange stories .
Basics of Me... | <urn:uuid:38d71226-fb2c-4737-a0c8-a7dff9658e1e> | 3.421875 | 748 | Documentation | Software Dev. | 48.797876 | 2,594 |
CALL me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of t... | <urn:uuid:791243c9-da65-43fe-bfcf-77b17d34fc66> | 3.125 | 482 | Comment Section | Science & Tech. | 47.881151 | 2,595 |
Common Lisp includes a complex and powerful “declaration”
mechanism that allows you to give the compiler special hints
about the types of data that will be stored in particular variables,
and about the ways those variables and functions will be used. This
package defines versions of all the Common Lisp declaration form... | <urn:uuid:fd5b0cdb-89ba-44e1-824a-892e3b77b07c> | 2.515625 | 1,406 | Documentation | Software Dev. | 43.674675 | 2,596 |
When you load a Haskell source module into GHCi, it is
normally converted to byte-code and run using the interpreter.
However, interpreted code can also run alongside compiled code in
GHCi; indeed, normally when GHCi starts, it loads up a compiled
copy of the
base package, which contains the
Why should we want to run c... | <urn:uuid:3dd9279f-584c-4b78-ba85-061403aacd14> | 2.890625 | 1,171 | Documentation | Software Dev. | 61.989842 | 2,597 |
Cheap, easy technique to snip DNA could revolutionize gene therapy
January 8, 2013
A simple, precise, and inexpensive method for cutting DNA to insert genes into human cells could transform genetic medicine, making routine what now are expensive, complicated and rare procedures for replacing defective genes to fix gene... | <urn:uuid:3393fa87-883a-40e0-9b41-07e62f5d39da> | 2.9375 | 1,315 | News Article | Science & Tech. | 31.619877 | 2,598 |
Water World: New Super-Earth Found Near Distant Star
By NED POTTER (@NedPotterABC)
Feb. 3, 2012
Pack your bags. But leave the bottled water behind; you might not need it.
Scientists have found a planet orbiting another star -- 22 light-years away -- and of all the hundreds of so-called exoplanets so far discovered, thi... | <urn:uuid:20e5631e-6a61-44c9-8b58-12045854104d> | 2.796875 | 836 | News Article | Science & Tech. | 62.033083 | 2,599 |