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Like many of science's greatest discoveries, the one that earned Arno Penzias his Nobel Prize was an event of pure serendipity. While tuning a small, yet very powerful and highly sensitive horn antenna for conducting radio astronomy experiments, Arno Penzias and Robert Wilson noted a constant low level noise disrupting... | <urn:uuid:262cb227-ca88-41fb-ae42-053a09620d14> | 4 | 385 | Knowledge Article | Science & Tech. | 28.330724 |
This week, Python 101 discusses how to abstract out parts of yourPython code into reusable functions, add flexibility to them by allowingthem to accept different arguments, and make them return specific values.Also included: a discussion of variable scope and functions to help youwrite your own functions. Confused? All... | <urn:uuid:c85d2f6d-b7eb-448c-9401-3948a4651898> | 4.4375 | 292 | Truncated | Software Dev. | 45.656802 |
Over the last two years, evidence has accumulated that the IPCC reports released just two years ago underestimate the pace of climate change. Nature provides this summary. See also this article in Science Daily; and there are plenty more like it;
Emissions from fossil fuels growing faster than any of the scenarios incl... | <urn:uuid:01c0b97a-2298-460a-a1e3-a13c6bef4900> | 2.8125 | 216 | Personal Blog | Science & Tech. | 29.451304 |
Water on Mars
In many ways, Mars is the most Earthlike of all the planets. A visitor would find that a day on Mars is only slightly longer than one on Earth. Mars is also tilted about the same amount as the Earth, so it has seasons.
Both Mars and Earth have white polar caps. Those on Mars are much smaller and thinner, ... | <urn:uuid:fbe61eaa-f5c3-4ffd-90e8-4f21f765ee27> | 3.78125 | 241 | Knowledge Article | Science & Tech. | 63.414531 |
The second Section concentrates on applications of remote sensing to geological studies. A list of principal uses begins this page. Special attention is given to ways in which remote sensing (especially through image classification) can aid in making geologic maps. The notion of "formation" is discussed and reasons giv... | <urn:uuid:50870d14-fb6b-4274-a714-0214f26184a3> | 4.0625 | 2,201 | Academic Writing | Science & Tech. | 24.12608 |
XBee is a radio transceiver sold by Digi Corporation which implements a network using the ZigBee standard (IEEE 802.15.4) or similar. A pair of XBee devices can provide a convenient point-to-point link for transferring serial data between a computer and a device (e.g. an Arduino).
In a point-to-point link one XBee devi... | <urn:uuid:be286d02-3c8c-4313-8f9b-7a689903f69d> | 2.953125 | 640 | Documentation | Software Dev. | 55.243867 |
|Feb1-13, 05:56 AM||#18|
Meaning of a "Flat," "Open," and "Closed" Universe
The spatial geometry refers to the sum of angles = 180° of a triangle at a certain instant of time. Or assuming the expansion is "frozen". The triangle shall be formed by an object of a known size (from one edge to the other) and the distance b... | <urn:uuid:29e511e5-0cbe-4729-8e4f-c1c4df2268a9> | 3.140625 | 1,290 | Comment Section | Science & Tech. | 54.554647 |
If p is the probability that a single amoeba's descendants will die
out eventually, the probability that N amoebas' descendents will all
die out eventually must be p^N, since each amoeba is independent of
every other amoeba. Also, the probability that a single amoeba's
descendants will die out must be independent of ti... | <urn:uuid:da5596b5-d3fc-44f4-90e8-279a33851219> | 3.09375 | 478 | Academic Writing | Science & Tech. | 95.611835 |
Web edition: September 7, 2012
Print edition: September 22, 2012; Vol.182 #6 (p. 4)
PIGMENT MAY HELP VISION — The same chemical that gives you that golden tan from the summer sun may also help you to see. The brown pigment, melanin, may take part in controlling the messages sent from the eye to the brain, Lieut. Raymon... | <urn:uuid:e6104f22-afdd-468c-b50a-f103f5e13ab9> | 2.921875 | 206 | Truncated | Science & Tech. | 65.092888 |
betatron acceleration \BAY-tuh-trahn
ak-seh-leh-RAY-shun\ n. Acceleration of
particles by a changing magnetic field.
The changes give particles, such as
electrons, an energy boost and send
them corkscrewing through space at
high speeds. Researchers led by Maha Ashour-Abdalla of UCLA reported
online January 30 in Nature... | <urn:uuid:7c042efb-0391-4de4-9fcb-186daaedf0a8> | 3.296875 | 864 | Content Listing | Science & Tech. | 57.930669 |
On Windows NT, 2000, and XP, the system stores file names as Unicode strings. Traditionally, Python has represented file names as byte strings, which is inadequate because it renders some file names inaccessible.
Python now allows using arbitrary Unicode strings (within the limitations of the file system) for all funct... | <urn:uuid:7d7d28fc-a954-42df-b197-fb4ccd8c1796> | 2.8125 | 236 | Documentation | Software Dev. | 38.538245 |
kenn at linux.ie
Thu Sep 14 23:39:38 IST 2000
On Wed, Sep 13, 2000 at 04:22:38PM +0100, John P . Looney wrote:
> On Wed, Sep 13, 2000 at 04:26:10PM +0100, Ross Davis mentioned:
> > Anybody got any pointers to information on how OIDs work, are used, etc.?
> > Really, I just want to know _why_ exactly SNMP, LDAP and the ... | <urn:uuid:e2d14929-e824-48bc-a777-db45b37ef54f> | 2.6875 | 738 | Comment Section | Software Dev. | 74.639639 |
Case Study: Hot, Cold, Fresh and Salty
Miss Sherwood wanted to review convection with her 9th grade earth science class. She had already taught convection in astronomy, meteorology, and geology. Reviewing convection made it really easy to demonstrate how temperature and density create ocean currents.
Using the online r... | <urn:uuid:d7368f48-f349-4324-b0eb-b300e0be29b8> | 4.125 | 689 | Knowledge Article | Science & Tech. | 33.253116 |
Just as polar bears are in critical danger as global warming melts the ice caps, limiting their habitat, Bengal tigers are also threatened by this phenomenon. Making their homes among the Sundarbans, a mangroves ecosystem in Bangladesh, Bengal tigers number around 4000 in the wild. As polar caps melt, sea levels will r... | <urn:uuid:57e69753-13e7-4e5b-9491-1966cacaed3f> | 3.65625 | 134 | Knowledge Article | Science & Tech. | 47.637296 |
Australia's best meteorite craters
Australia has 30 impact craters out of 176 recognised worldwide. See our gallery of some of the best.
The Wolfe Creek crater in Western Australia is the best known meteorite crater in Australia. (Image: Dick and Pip Smith)
Australia's best meteorite craters
AUSTRALIA IS AN ANCIENT lan... | <urn:uuid:9cc0b166-7e3b-4fff-8fb5-a26c6c0db0f4> | 2.984375 | 746 | Knowledge Article | Science & Tech. | 39.792402 |
Peale's dolphins are a little-known species that inhabit the waters around the southern tip of South America. They live in small family units of 3-8.
Scientific name: Lagenorhynchus australis
The Peale's dolphin can be found in a number of locations including: South America. Find out more about these places and what el... | <urn:uuid:1505a190-b775-4c00-ac02-e7b02ec3a150> | 3.421875 | 311 | Knowledge Article | Science & Tech. | 51.5575 |
Logo for "Nota Bene / non-blog" goes here. NB main page
Along with navigation links.
16 June 2007
Space and time are truely intertwined that it makes to sense to speak of time as being separate from space. The reasons they must be taken together will be explored in more detail later. But, this essay concentrates on und... | <urn:uuid:e7326ac1-20b2-474e-812c-03c22cd07b5e> | 2.6875 | 2,846 | Personal Blog | Science & Tech. | 56.581239 |
We're finding (potentially) habitable exoplanets more and more frequently, to the point where spotting another one is just not news unless it has two suns or something. New data from the Kepler space telescope may make further exoplanet discoveries even less exciting, now that we can guess just how many of them might b... | <urn:uuid:7f688c9a-e3a1-47a3-ae6d-455add09767b> | 3.21875 | 282 | Personal Blog | Science & Tech. | 32.99 |
What is Geothermal Energy?
Geothermal energy is a clean, renewable energy source that is made from the heat of the Earth's crust.
How Does Geothermal Energy Work?
The temperature of the Earth’s surface and surrounding air will change with the different seasons. What you may not know is that the temperature under the Ea... | <urn:uuid:9f541b2b-c84b-4024-b6b8-66a8f0b5d7ea> | 3.640625 | 663 | Knowledge Article | Science & Tech. | 57.929679 |
Drag any vertex of the square below. It will remain a square and the length of the diagonal will be calculated.
A square has two diagonals. Each one is a
drawn between the opposite
vertices (corners) of the square.
The diagonals have the following properties:
- The two diagonals are
congruent (same length).
In the figu... | <urn:uuid:ff40f0f2-241a-4059-abb8-6edd95f1493d> | 3.765625 | 406 | Tutorial | Science & Tech. | 53.454631 |
The Florida stone crab and the gulf stone crab were once one
species. Changes in climate and sea level probably kept two
populations separate over time until they became genetically
Two species of stone crabs
exist in the Southeastern United States: Menippe
mercenaria in the peninsula of Florida, and Menippe
adina in t... | <urn:uuid:33dc33d1-ffd5-4d6a-a644-525353062ca4> | 3.96875 | 1,199 | Knowledge Article | Science & Tech. | 34.340569 |
Monday, March 20, 2006
Global Warming Research Fears: Galileo Would Have Recognized the FeelingKudos to the Canadians, as the Ottawa Citizen has published an article about University of Ottawa Science Professor Jan Veizer's new global warming theory.
The article begins:
A prominent University of Ottawa science professo... | <urn:uuid:66b7cca2-4e15-4974-ab40-b481fe4d475f> | 2.734375 | 569 | Personal Blog | Science & Tech. | 51.65481 |
Grolar Bears and Narlugas: Rise of the Arctic Hybrids
In 2006 an American hunter shot an animal in the far north of Canada’s Northwest Territories that shared characteristics of a polar bear and a grizzly. Earlier this year, a similar bear was killed less than 200 miles away, and DNA tests confirmed it was a mixture of... | <urn:uuid:0a3d8037-4b1c-4447-801d-fa7feb25065c> | 3.71875 | 1,531 | Nonfiction Writing | Science & Tech. | 40.278878 |
|Sep28-08, 08:33 PM||#1|
Four resistors are connected to a battery as shown in the figure. The current in the battery is I, the battery emf is E, and the resistor values are R1 = R, R2 = 2R, R3 = 4R, and R4 = 3R.
-Determine the potential difference across each resistor in terms of E.
-Determine the current in each resi... | <urn:uuid:157c709d-5b86-44fd-8148-cc515226abe6> | 3.515625 | 545 | Comment Section | Science & Tech. | 82.514446 |
|Aug5-05, 09:50 PM||#1|
Minkowski spacetime interval's Lorentz invariance
Maybe this is really easy, but...
Can someone show me how the sign reversal between the space and time components of Minkowski spacetime make its intervals Lorentz invariant (mathematical derivation) ? Thanks....
|Aug6-05, 02:08 AM||#2|
Assuming ... | <urn:uuid:e3cdc3db-0ba0-40fd-9ed4-37a6d45d8187> | 2.78125 | 927 | Comment Section | Science & Tech. | 69.560278 |
how to change cell shape?
Posted 08 October 2009 - 09:56 AM
Posted 17 November 2009 - 01:04 PM
A 5$ physical posibility,
Imagine a room that get smaller as you advance you there will be a point at which you can advance, but if you were forced to advance you would squeeze as much as you can, till becoming flat. As que h... | <urn:uuid:1b2eb344-e37b-4e3d-b754-a03081c26518> | 3.046875 | 769 | Comment Section | Science & Tech. | 53.239128 |
Data Frame Column Vector
We reference a data frame column with the double square bracket "[]" operator.
For example, to retrieve the ninth column vector of the built-in data set mtcars, we write mtcars[].
We can retrieve the same column vector by its name.
We can also retrieve with the "$" operator in lieu of the doubl... | <urn:uuid:8d965229-f724-4a58-8a7f-0aa2241da675> | 3.125 | 121 | Documentation | Software Dev. | 46.933333 |
The evolution of the eye has been a subject of significant study, as a distinctive example of a homologous organ present in a wide variety of species.
The development of the eye is considered by most experts to be monophyletic; that is, all modern eyes, varied as they are, have their origins in a proto-eye believed to ... | <urn:uuid:25b4eb78-5b07-4f3a-8414-852b53e8f24f> | 3.859375 | 359 | Knowledge Article | Science & Tech. | 27.187292 |
Aug. 20, 2004 In a dramatic ending that marks a beginning in scientific research, NASA's Genesis spacecraft is set to swing by Earth and jettison a sample return capsule filled with particles of the Sun that may ultimately tell us more about the genesis of our solar system.
"The Genesis mission -- to capture a piece of... | <urn:uuid:59218359-30e0-4665-8603-d37b687fd0a7> | 3.25 | 918 | Truncated | Science & Tech. | 43.710148 |
Boston Harbor/Massachusetts Bay Studies research project conducted as part of Boston Harbor cleanup to predict the fate of contaminants and sediments introduced to Massachusetts' coastal waters from sources that include Boston sewage outfall.
Wetlands and oil wells shouldn't mix, but in some areas they do. This explain... | <urn:uuid:6e7674f6-b592-4a21-bcfb-d557f65df25e> | 3.234375 | 311 | Knowledge Article | Science & Tech. | 23.955313 |
On my homework, I came across a reference to a molecule with a formulae of XeF4. Is such a molecule possible? or is my teacher mistaken..
And how is NO2 bonded? Nitrogen has 3 available covalent bonds while Oxygen has 2. Is this case similiar to that of CO where co-ordinate covalencies are involved or what? I've tried ... | <urn:uuid:4078a9f9-331d-4de8-addc-a7458cc7ea00> | 2.84375 | 127 | Q&A Forum | Science & Tech. | 61.818565 |
Giant Squid - (Architeuthis dux)
|page: 1 2 3 4|
How are giant squid studied? (Sources of information)
Whether found floating at sea or washed ashore as flotsam (debris), giant squid have been reported in records dating back to the 16th Century. No doubt, these fabulous creatures have been scattered around the world’s ... | <urn:uuid:aeeff37c-535a-4fb7-86b6-e9e1233b61de> | 3.90625 | 1,061 | Knowledge Article | Science & Tech. | 57.525129 |
In almost all reactions, matter is conserved: it is not created or destroyed, only transformed from one type into another. Therefore, you must have the same amount of matter on one side of a reaction as you have on the other. The molecules may be formed, destroyed, or changed, but the individual atoms remain. There is ... | <urn:uuid:e798b4e0-2871-4b76-8aa0-e84589acd26e> | 4.40625 | 1,363 | Tutorial | Science & Tech. | 69.918328 |
About this image
This THEMIS visible image shows Dao Vallis, a large outflow channel that starts on the southeast flank of a large volcano called Hadriaca Patera and runs for 1000 kilometers southwest into the Hellas impact basin. The channels up to 20 kilometers wide near its source, but narrows downstream. As can be ... | <urn:uuid:033d858a-e8b4-412c-8bc3-9e2a38f06c25> | 3.265625 | 313 | Knowledge Article | Science & Tech. | 39.844184 |
The rise in number of recognized reptile species through the years.
The number of described species of reptiles has increased extraordinarily in recent times. In a fascinating recent article, Pincheira-Donoso and colleagues have catalogued this increase, as well as describing the taxonomic distribution of present-day r... | <urn:uuid:360c9887-2815-46da-b81c-54936aee6da2> | 2.984375 | 2,102 | Content Listing | Science & Tech. | 20.008521 |
updated: 22-MAR-1993 by SIC
There was a young lady named Bright, Whose speed was far faster than light. She went out one day, In a relative way, And returned the previous night! -Reginald Buller
It is a well known fact that nothing can travel faster than the speed of light. At best, a massless particle travels at the s... | <urn:uuid:4aa536df-00c2-47aa-bc4c-8215882d8627> | 3.625 | 1,503 | Knowledge Article | Science & Tech. | 64.574995 |
© Courtesy of BioMed Central Ltc. From: Maddelena Arigoni et al. "A novel Dictyostelium RasGEF required for chemotaxis and development," BMC Cell Biology, 7 December 2005.
In a striking example of emergent behavior, cells of the slime-mold Dictyostelium form an aggregate in response to the signaling molecule cyclic AMP... | <urn:uuid:a07e9bb5-7873-4aad-8d9d-e51a4eb42ec5> | 2.78125 | 151 | Knowledge Article | Science & Tech. | 27.603066 |
Oceanography data that will help scientists around the world better understand climate change are now available.
Less than a month after launch, the new NASA-French space agency Jason 2 oceanography satellite has produced its first complete maps.
08.06.09 - Fully calibrated, validated data from the NASA-French Space Ag... | <urn:uuid:191b125e-aee7-4b74-b18a-122841d14d2d> | 2.921875 | 231 | Content Listing | Science & Tech. | 43.136917 |
Amplitude for Richter Scale
Name: Robin W.
Country: United States
Date: August 6, 2005
This is a great idea.
My question is that when measuring the
seismographic amplitude for the Richter scale what amplitude do I use?
1. max S-wave amplitude
2. max L-wave amplitude
3. mean S-wave amplitude
4. mean L-wave amplitude
The... | <urn:uuid:f8b37b28-5983-438e-a4dc-1899f3f383f8> | 3.359375 | 206 | Q&A Forum | Science & Tech. | 52.792486 |
An Harshad number, or Niven number in a given number base, is an integer that is divisible by the sum of its digits when written in that base. Harshad numbers were defined by D. R. Kaprekar, a mathematician from India. The word "Harshad" comes from the Sanskrit harṣa (joy) + da (give), meaning joy-giver. The Niven numb... | <urn:uuid:c3aa4b0b-2cad-4f62-aa08-aa29c77a734c> | 2.78125 | 270 | Knowledge Article | Science & Tech. | 62.925382 |
Atomic Emission are used as light sources for atomic absorption spectrometers, which detect the presence of elements by seeing whether a sample absorbs the very specific wavelengths of light associated with the electronic transitions of the given element. The lamp uses an electric arc to stimulate the element it contai... | <urn:uuid:7f34972b-dc62-4796-b158-32419bac2d97> | 3.609375 | 246 | Knowledge Article | Science & Tech. | 39.815291 |
by Staff Writers
Munich, Germany (SPX) Aug 08, 2011
Scientists operating Europe's gravitational wave observatories have combined efforts this summer to search for gravitational waves. This groundbreaking research is being taken forward in Europe while similar US-based detectors undergo major upgrade work.
Cataclysmic c... | <urn:uuid:7649b138-c98c-417a-96da-95e66477da27> | 3.5625 | 978 | Truncated | Science & Tech. | 23.98971 |
Introduction to Cloning
UPDATE: Dolly the sheep was
killed on 16th February as she had a lung disease. Read
story here. What's next?
To be able to cure illnesses or make plants healthier,
a scientist needs to clone a Gene, which involves making
many copies of the gene. This is done in a laboratory,
and the method is ca... | <urn:uuid:ccfb2f08-8e85-481c-ad8a-69a9168c20c2> | 3.859375 | 283 | Truncated | Science & Tech. | 51.778298 |
What did the inventor of e-mail write in the first e-mail message? Find out on this Moment of Science.
Learn more about Dr. Robert Bartholow and his electricity on this Moment of Science.
How much do babies actually look like their parents? Find out on this Moment of Science.
Americans have a long and august history of... | <urn:uuid:40d0cc53-8458-4e04-b8c9-829f67fac0a3> | 2.71875 | 503 | Content Listing | Science & Tech. | 63.313253 |
A robot ship could soon be sailing across the massive bodies of liquid that dot the arctic region of Titan, Saturn's moon. Titan has huge lakes, but they're made up of ethane, methane and propane.
In the plans drafted by geologist Ellen Stofan, with funding from NASA, a capsule would splash down in one of these norther... | <urn:uuid:40a1736f-bd2b-4d7c-9426-749ed7b5f887> | 3.265625 | 324 | Truncated | Science & Tech. | 56.027512 |
1.1 What is Ruby?
Ruby is a pure object-oriented programming language with a super clean syntax that makes programming elegant and fun. Ruby successfully combines Smalltalk’s conceptual elegance, Python’s ease of use and learning, and Perl’s pragmatism. Ruby originated in Japan in the early 1990s, and has started to be... | <urn:uuid:e899ce29-43fe-4646-ac6c-4b3aee0b9263> | 3.40625 | 100 | Q&A Forum | Software Dev. | 50.641429 |
Number & Operations for Teachers
Copyright David & Cynthia Thomas, 2009
Modeling Multiplication with Regrouping
In addition to understanding the meaning of multiplication and division and their properties, students must also become fluent in performing complex arithmetic computations involving these operations. For man... | <urn:uuid:d37f54d1-24a8-42f3-ad3e-f65a74d4d78c> | 4.40625 | 535 | Tutorial | Science & Tech. | 48.857892 |
Magnificent CME Erupts on the Sun with Earth to Scale (por NASA Goddard Photo and Video)
On August 31, 2012 a long filament of solar material that had been hovering in the sun’s atmosphere, the corona, erupted out into space at 4:36 p.m. EDT. The coronal mass ejection, or CME, traveled at over 900 miles per second. The... | <urn:uuid:684f3cc7-19ff-437d-aee5-cd59f5946c7a> | 3.25 | 155 | Personal Blog | Science & Tech. | 59.696158 |
The media are also full of a new methane scare. An article in Science is said to claim that the Siberian Arctic bubbles release much more methane to the atmosphere than expected (by someone who had wrong expectations). For example, the Daily Mail says:
The concentration of methane in the atmosphere is really tiny, just... | <urn:uuid:752ab261-c709-4290-87fc-f6777ae058de> | 3.109375 | 824 | Personal Blog | Science & Tech. | 55.439855 |
Arctic Sea Ice – for how long still?
Friday, September 30, 2005 6:20:06 PM
In most places I have seen evidence and/or been told by guides or local people that they are retreating. Because of global warming? Who am I to tell.
The arctic sea ice cover also seems to melt at a dramatic pace a.o. according to BBC News – Arc... | <urn:uuid:67fac4c3-0716-434b-9e3c-3b6d8bd80792> | 2.765625 | 242 | Personal Blog | Science & Tech. | 59.04034 |
A thoughtful shepherd used bales of straw to protect the area
around his lambs. Explore how you can arrange the bales.
What can you say about these shapes? This problem challenges you to
create shapes with different areas and perimeters.
Can you draw a square in which the perimeter is numerically equal
to the area?
How... | <urn:uuid:0986f5f8-2984-4140-ac02-1090bdcb6c57> | 3.609375 | 1,348 | Content Listing | Science & Tech. | 61.624171 |
- First, what determines the strength of an RF signal?
- Why is it said that a cellphones radiates more energy when the reception from signal tower is lower in strength.
- Why is it said that RF gets transmitted along wires such as in wired headsets making them act as antennae?
- Is it then safer to use bluetooth heads... | <urn:uuid:ce872513-4b95-426c-96a8-051f7f832450> | 2.84375 | 95 | Q&A Forum | Science & Tech. | 63.393842 |
An alkali atom has a single outer electron that interacts with incoming photons of the right wavelength (for alkalies it's in the visible & IR range). If there is an external magnetic field, the electron has a well defined quantization axis and the the incoming light can be separated into three components: linearly pol... | <urn:uuid:2a28543b-ee84-4a45-b25d-d57327323c93> | 2.75 | 172 | Q&A Forum | Science & Tech. | 22.411667 |
In the Australian summer of 2008–2009, the shores of the Gippsland Lakes in Victoria were awash with an algae known as Noctiluca scintillans. A remarkable chain of events led to this never-seen-before occurence. In 2006, Victoria suffered from alpine bushfires that ravished over a million hectares for 69 days, includin... | <urn:uuid:185349bd-9229-446e-89c9-3cb072508c6d> | 3.578125 | 241 | Personal Blog | Science & Tech. | 31.651893 |
The cause of the 12 April gamma-ray flare, described at the Third Fermi Symposium in Rome, is a total mystery.
It seems to have come from a small area of the famous nebula, which is the wreckage from an exploded star.
The object has long been considered a steady source of light, but the Fermi telescope hints at greater... | <urn:uuid:014714a1-e8b1-462a-9a95-4f5f43dca6c0> | 4 | 299 | Truncated | Science & Tech. | 48.918741 |
Tue, Mar 06, 2012
Confirms The Moon Of Saturn Has A 'Very Tenuous Atmosphere'
NASA's Cassini spacecraft has "sniffed" molecular oxygen ions around Saturn's icy moon Dione for the first time, confirming the presence of a very tenuous atmosphere. The oxygen ions are quite sparse - one for every 0.67 cubic inches of space... | <urn:uuid:3fbe486f-7a5e-4f8c-8e86-72a4043de382> | 3.578125 | 874 | Content Listing | Science & Tech. | 49.170163 |
Science Fair Project Encyclopedia
Radionuclides are often referred to by chemists and biologists as radioactive isotopes or radioisotopes, and play an important part in the technologies that provide us with food, water and good health. Radionuclides may occur naturally, but can also be artificially produced.
Artificial... | <urn:uuid:a76f0a94-e20c-49e3-908f-3d30a35dcbcf> | 4.40625 | 942 | Knowledge Article | Science & Tech. | 22.449917 |
about a little Amphibian Trivia to test your knowledge of the Amphibian species?!
from primitive fish over 350 million years ago, amphibians, with their primitive
legs and lungs, became the first vertebrates to conquer land. They remain,
however, linked to the aquatic environment they left, spending at least some
part ... | <urn:uuid:58bf2e5d-3e03-4ccf-a5cf-e1761a3dd677> | 3.328125 | 145 | Knowledge Article | Science & Tech. | 46.95125 |
baseArticle Free Pass
base, in chemistry, any substance that in water solution is slippery to the touch, tastes bitter, changes the colour of indicators (e.g., turns red litmus paper blue), reacts with acids to form salts, and promotes certain chemical reactions (base catalysis). Examples of bases are the hydroxides of... | <urn:uuid:f79e0f01-03a9-45c1-83da-256d11754ca7> | 3.609375 | 186 | Knowledge Article | Science & Tech. | 40.190386 |
Current Group Research
Nitro-polycyclic Aromatic Hydrocarbons
Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) constitute one of the most important classes of environmental pollutants, found in air, aquatic systems, grilled food, and sediments. Nitro-PAHs are released to the environment as a result of direct emissio... | <urn:uuid:d0f594e9-1096-4c3c-80fa-795eee4ba46a> | 2.859375 | 620 | Academic Writing | Science & Tech. | 43.086793 |
Global fields of mean lower-tropospheric temperature are derived from channel-2R of the Microwave Sounding Unit (MSU) flown aboard the NOAA series of polar-orbiting satellites (Spencer et al. 1990). Most of the earth is sampled twice daily from each of two MSU instruments flying concurrently on different satellites. Th... | <urn:uuid:bfa34f97-89c0-4e17-9c93-6a1b3db0fba3> | 3.34375 | 1,216 | Academic Writing | Science & Tech. | 27.846659 |
C++ How to Program, 4/e Tour of the Book (Continued)
Chapter 9 Object-Oriented Programming: Inheritance
Introduces one of the most fundamental capabilities of object-oriented programming languages. Inheritance is a form of software reusability in which programmers create classes that absorb an existing class's data and... | <urn:uuid:f929b95f-363a-40ad-b8e0-fb8552d86f68> | 4.375 | 1,124 | Content Listing | Software Dev. | 20.915078 |
make-sequence result-type size &key initial-element => sequence
Arguments and Values:
result-type---a sequence type specifier.
size---a non-negative integer.
initial-element---an object. The default is implementation-dependent.
sequence---a proper sequence.
Returns a sequence of the type result-type and of length size,... | <urn:uuid:f82e5837-1d27-4b13-8e30-4a0d3acd8b4b> | 3.03125 | 383 | Documentation | Software Dev. | 50.206232 |
Gnamptogenys hartmanni and G. triangularis are the only two members of the subfamily Ectatomminae known to occur in the southeastern US. These very distinctive ants can be recognized immediately by their relatively large size (3.5-5.0 mm in total length), the deep horizontal grooves covering the entire body, and single... | <urn:uuid:7203e4fd-3906-4af5-ac34-68f78dda8aba> | 2.8125 | 376 | Knowledge Article | Science & Tech. | 50.19267 |
Patent law prohibits creating a monopoly on mathematical theories. So authors try to dress up theory as mechanical invention.
Randell Mills of Chochranville in Pennsylvania does this in his patent application (WO 90/16073) for 'an apparatus and method for providing an anti-gravitational force'. He says Einstein's theor... | <urn:uuid:5a773bda-9f2c-47e9-8af7-2fd8bebe7955> | 3.078125 | 227 | Truncated | Science & Tech. | 28.805824 |
Published in Proteomics Weekly, September 15th, 2008
A study published online this week in Nature by an international team that included Cornell University researchers describes the use of DNA to predict the geographic origins of individuals from a sample of Europeans, often within a few hundred kilometers of where the... | <urn:uuid:8e5f3297-e6ab-4ffd-9c65-38b610674e98> | 3.09375 | 178 | Truncated | Science & Tech. | 29.423023 |
Photo Credit: Scott Gravette
SCIENTIFIC NAME: Ambystoma maculatum
DESCRIPTION: Adult spotted salamanders are typically six to eight inches long but may grow as large as 10 inches. As the name suggests this species is identified by a series of irregular shaped yellow, sometimes orange, spots running down either side of ... | <urn:uuid:1d267125-a94c-4f6b-9457-f936ce6bd681> | 3.296875 | 1,156 | Knowledge Article | Science & Tech. | 44.40305 |
The idea of a medieval warm period was formulated for the first time in 1965 by the English climatologist Hubert H. Lamb . Lamb, who founded the UK Climate Research Unit (CRU) in 1971, saw the peak of the warming period from 1000 to 1300, i.e. in the High Middle Ages. He estimated that temperatures then were 1-2 ° C ab... | <urn:uuid:80dba736-47a7-4f91-a0f1-97eaa128d714> | 4.1875 | 1,699 | Nonfiction Writing | Science & Tech. | 46.724232 |
Jellyfish (also known as jellies or sea jellies or a stage of the life cycle of Medusozoa) are free-swimming members of the phylum Cnidaria. Medusa is another word for jellyfish, and refers to any free-swimming jellyfish life stages among animals in the phylum. Jellyfish have multiple morphologies that represent cnidar... | <urn:uuid:443b9ff0-e22b-4173-9301-1f2e1f3a5479> | 3.6875 | 365 | Knowledge Article | Science & Tech. | 30.965789 |
Let’s look back on the month of March, as well as the three-month period comprising January, February, and March. As always, the information provided below is courtesy of our friends at the National Climatic Data Center, in Asheville, North Carolina, as well as from our local National Weather Service Forecast Office in... | <urn:uuid:f5d6090a-421f-4ed3-b7a0-2f0e54fb25dc> | 2.859375 | 541 | Knowledge Article | Science & Tech. | 44.530527 |
When "scientific consensus" is referred to in relation to climate change, it's referring to the following points:
Numerous survey studies have been done, and the results are overwhelmingly in favor of scientific consensus that the earth is warming and human activity is the cause. Surveys done by reputable organizations... | <urn:uuid:89f73798-e4a2-44b6-832a-02bc8d7cd2e2> | 3 | 1,974 | Content Listing | Science & Tech. | 41.016415 |
(or more accurately, 55P/Tempel-Tuttle)
was discovered independently
by William Tempel
in December 1865 and by
in January 1866.
It was calculated that the comet had an
elliptic orbit with a 33-year period.
This information was then used to prove that
Tempel-Tuttle was the same comet that had been
observed by early astr... | <urn:uuid:c06c4e03-6069-4334-807b-3d4dafa2c246> | 3.71875 | 254 | Knowledge Article | Science & Tech. | 45.454317 |
The Amazing Diversity of Pigeons
Studying pigeon genetics could offer insight into how various traits have evolved in wild birds.
Free-living pigeons are so ubiquitous they often go unnoticed, yet the species is remarkably diverse. The 350-plus breeds display traits ranging from curly feathers to stumpy beaks. But simi... | <urn:uuid:78a2aa38-4c6e-4766-aca1-f7563dd7df26> | 3.921875 | 251 | Truncated | Science & Tech. | 40.012769 |
These two group activities use mathematical reasoning - one is
numerical, one geometric.
Suppose there is a train with 24 carriages which are going to be
put together to make up some new trains. Can you find all the ways
that this can be done?
There are 4 jugs which hold 9 litres, 7 litres, 4 litres and 2
litres. Find ... | <urn:uuid:7a0e2b9d-d47d-42af-9094-24b32a04b313> | 4.03125 | 1,552 | Content Listing | Science & Tech. | 77.104752 |
Radiation from Japan found in kelp off US West Coast
This file photo shows a girl dragging kelp along a beach in California. Radioactive iodine was found in kelp off the US West Coast following last year's earthquake-triggered Fukushima Daiichi nuclear meltdown, according to a new study.
Tuesday, April 10, 2012
The inf... | <urn:uuid:87b66ccc-c7bc-4dbd-b45e-33752dbf1488> | 2.734375 | 148 | Truncated | Science & Tech. | 35.12 |
Some anti-nuclear sites are using an earthquake map from the LA Times on April 28, 2010 that show the Newport-Inglewood fault in red, indicating an earthquake potential of 7.5 – 8.0. I didn’t know whether to flee first, or take the time to look into it first. Remember, with great power of earthquakes comes great respon... | <urn:uuid:7ad03175-c127-4368-a89a-d6d26088b358> | 2.71875 | 1,255 | Personal Blog | Science & Tech. | 73.304284 |
Understanding air density and its effects
By Jack Williams, USATODAY.com
In simple terms, density is the mass of anything - including
air - divided by the volume it occupies.
In the metric system, which scientists use, we usually
measure density in terms of kilograms per cubic meter.
The air's density depends on its te... | <urn:uuid:9e26588f-4189-4c36-9011-7e6e73529bf7> | 4.125 | 1,864 | Knowledge Article | Science & Tech. | 51.264326 |
1. Draw a perpendicular to a line proportional to the gnomon.
2. Determine length of equinoctial shadow.
3. Mark off this length on gnomon. (For "Observatory Park" latitude the equinoctial shadow for a 20' gnomon is 15' 6".)
4. From the point of intersection of gnomon and line, make a mark to the right on the line and ... | <urn:uuid:c163301d-f0f2-46ef-8614-1282ca23a38f> | 3.796875 | 462 | Tutorial | Science & Tech. | 60.990094 |
Nearby and bright, spiral galaxies M65 (top) and M66
stand out in this
The pair are just 35 million light-years distant and around
100,000 light-years across, about the size of our own
spiral Milky Way.
While both exhibit prominent dust lanes sweeping along
their broad spiral arms,
M66 in particular is a striking
contr... | <urn:uuid:1da511a5-8d07-4819-948d-48156b1b5127> | 3.03125 | 161 | Knowledge Article | Science & Tech. | 53.81592 |
An absorption spectrum is a diagram depicting the wavelengths of electromagnetic radiation absorbed by a material, usually a gas. It can be regarded as the opposite to an emission spectrum, which is a depiction of the specific wavelengths emitted by a material.
Let us consider white light, which consists of electromagn... | <urn:uuid:f3de8f1b-4af4-4dd0-b020-8cd4e8f8f162> | 3.890625 | 293 | Knowledge Article | Science & Tech. | 29.875682 |
Algorithms and data structures in C/C++
All programmers should know something about basic data structures like stacks, queues and heaps. Graphs are a tremendously useful concept, and two-three trees solve a lot of problems inherent in more basic binary trees.
Algorithmic Efficiency and Sorting and Searching Algorithms
... | <urn:uuid:d77cdfaf-e769-42f9-a6e8-9c0034eebcb4> | 3.078125 | 167 | Content Listing | Software Dev. | 30.990887 |
These images are snapshots of a real-time level of detail planet renderer
which I wrote last year.
The complete source code is available on my web site:
Please feel free to use/abuse it for anything you want.
I did the project for fun and the technique used was invented on-the-fly.
Basically, the program starts with an... | <urn:uuid:be46407c-e9e1-4f37-836e-05df6e124b59> | 2.75 | 429 | Personal Blog | Software Dev. | 38.753472 |
Masses or Volumes from Electrolysis.
The electrolysis of molten aluminium
oxide - Al2O3
produces aluminium at the cathode and oxygen at the anode.
See the extraction of aluminium for more detail.
A current of 10
amps is allowed to flow
through molten aluminium oxide for 5 hours.
What mass of aluminium is deposited at t... | <urn:uuid:1957dc17-dc5d-4563-8316-07a65b69349a> | 3.234375 | 439 | Tutorial | Science & Tech. | 72.624153 |
Oceans and seas cover the majority of the planet's surface. From the coral reefs and their abundance of life, to the solitary creatures that lurk in the depths, the oceans are home to some of the planet's most unusual creatures. Meet our marine animals.
Perhaps the most formidible predator of the open ocean. The great ... | <urn:uuid:6fea8049-8b19-4d2a-b89d-c580d54f4984> | 2.703125 | 168 | Knowledge Article | Science & Tech. | 44.358941 |
In the Southwest, rivers shape our lives. They guide the locations of our cities, agriculture and recreation.
The Gila, Mimbres and San Francisco Rivers in southwestern New Mexico nourished the early Mogollon and Mimbres Indians. Later, they supported the Apaches, Spanish homesteaders, explorers, trappers, pioneers and... | <urn:uuid:2284c738-3559-4413-947f-d93d06f3b761> | 3.5625 | 606 | Knowledge Article | Science & Tech. | 31.238047 |
Old Version of .Net Framework for Windows NT 4.0
Legacy OS support
Screenshots are not available for this software
The .NET Framework created by Microsoft is a software development platform focused on rapid application development (RAD), platform independence and network transparency. .NET is Microsoft's strategic init... | <urn:uuid:851beff4-9d66-4045-be35-d262f2383587> | 3.1875 | 288 | Knowledge Article | Software Dev. | 30.214296 |
MYTH: Recent cold winters and cool summers don’t feel like global warming to me.
FACT: While different pockets of the country have experienced some cold winters here and there, the overall trend is warmer winters.
Measurements show that over the last century the Earth’s climate has warmed overall, in all seasons, and i... | <urn:uuid:38eb0b81-ca3f-4800-9326-cffe64a585ad> | 3.265625 | 611 | Personal Blog | Science & Tech. | 42.832943 |
What are interference fringes? What shape are they? Why do they occur in the wild? If these are questions that you have pondered/are pondering, then you have come to the right page! To understand more about interference and the fringes that result, one must understand wave motion. In our case, the waves are light, but ... | <urn:uuid:e47b2f10-ed79-4ba9-83e7-61b5d0ae5101> | 4.0625 | 1,183 | Academic Writing | Science & Tech. | 51.696082 |
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and ... | <urn:uuid:9124d36f-6c4f-4cf3-84b7-96872d9e31e3> | 3.578125 | 344 | Content Listing | Science & Tech. | 60.677135 |
ANT - Environment Setup
Installing Apache Ant
It is assumed that you have already downloaded and installed Java Development Kit (JDK) on your computer. If not, please follow the instructions here.
Apache Ant is distributed under the Apache Software License, a fully-fledged open source license certified by the open sour... | <urn:uuid:be7c32bc-1923-400d-b9f4-aba19a3ec586> | 2.8125 | 392 | Tutorial | Software Dev. | 51.758365 |
Versioning XML Vocabularies
by David Orchard | Pages: 1, 2
When a new version of a language is required, and it is backwards compatible with the older language, then the author must make a decision about the namespace name for names in the new language. There are two choices: create a new namespace name or reuse the ex... | <urn:uuid:9eccf847-5622-4d7c-8264-18e056458644> | 2.921875 | 2,975 | Documentation | Software Dev. | 32.939872 |
Eugene Chan, 29
Aims to speed genome sequencing with a machine that reads DNA letter by letter
Most biotech firms have their origins in labs, but Eugene Chan dreamed up U.S. Genomics in the medical-school dorms and libraries of Harvard University. His goal: to find a quicker, cheaper, more precise way to analyze DNA so... | <urn:uuid:b840cdae-40d8-46b7-b80b-5a14acc27f3d> | 3.125 | 275 | Nonfiction Writing | Science & Tech. | 49.459423 |
This one has been bugging me, so I'm hoping someone can help me through it (I also think it would make a good question to answer on Astronomy Cast).
How does a black hole rotate? I can visualize how objects like planets and stars rotate because they have a finite spherical shape and whole thing is in rotation about the... | <urn:uuid:d6cf02c2-e1a4-4445-8c4c-6333da79a59c> | 3.375 | 187 | Comment Section | Science & Tech. | 53.616989 |
Also referred to as PIC. This is compiled code that doesn't use any absolute addresses. For example, instead of an instruction "jump to 0x00A01857" it would use "jump to the current address plus 0x9A63". Same goes for variables, etc. Usually this is not needed because the processor's MMU creates a virtual address space... | <urn:uuid:727787d1-47fb-4a2f-a4d2-91e2759194ca> | 2.765625 | 105 | Knowledge Article | Software Dev. | 56.310278 |
What is Bionics?
BIONICS - in an formed from biology and technique - is a still recent science discipline, in which biologists and technicians co-operate interdisciplinary.
With plants and animals one finds mechanisms, which are superior to the technical solutions of humans. They were optimally adapted and perfected by... | <urn:uuid:45981dec-58db-4c8b-a692-2376fe175200> | 2.859375 | 215 | Knowledge Article | Science & Tech. | 36.594864 |
See also the
Browse High School Physics/Chemistry
Stars indicate particularly interesting answers or
good places to begin browsing.
- Can the Bus Cross the Gap? [9/15/1996]
We want to show that it is possible for a bus to cross a 50 ft. gap in a
- Definition of a Vector [02/28/2002]
I would like a "proper" definition o... | <urn:uuid:677f1eb0-c0a3-49c8-b7d8-3a08132d6a03> | 3.65625 | 1,740 | Q&A Forum | Science & Tech. | 71.655499 |
June 29, 2012
We saw the streaming median problem in a recent exercise. Today we look at a slight variant on that problem, the sliding median, which slides a window of width k over an input stream, reporting the median of each successive window.
The streaming median required us to keep the entire input stream in memory... | <urn:uuid:e8257042-f675-42d4-8d21-9a7e5ee7b6da> | 2.859375 | 225 | Tutorial | Software Dev. | 59.057885 |
The curious case of NGC 6397
Can a globular cluster create an open cluster? NGC 6397 may have done just that.
March 28, 2005
|In a 1996 paper, a team led by John Wallin of George Mason University in Fairfax, Virginia, noted that a globular cluster passes through the Milky Way's disk every million years or so. The astro... | <urn:uuid:24d87d4d-b4ab-44f5-a039-9c6aab873862> | 3.328125 | 295 | Truncated | Science & Tech. | 47.002189 |
Numerical Model Description
From our basic definitions and theory we have,
for the concentration change(DC) in a time Dt. Equation (1) can be used to find the concentration C at anytime if its initial value and the total emissions are known. The model described by equation (1) has been created for you to use, explore, ... | <urn:uuid:503cddd1-4768-4b86-b06a-ca3abc072587> | 3 | 417 | Documentation | Science & Tech. | 53.635217 |
DNA from a eukaryotic organism is digested with a restriction endonuclease
and the resulting fragments cloned into a plasmid vector. Bacteria transformed by these plasmids collectively contain all of the genes of the organism. This culture of bacteria is refereed to as a:
When the genomic DNA is digested by a restricti... | <urn:uuid:8775fc13-4b36-46cd-a851-cc84e3c46d81> | 3.171875 | 135 | Knowledge Article | Science & Tech. | 20.72 |