text stringlengths 174 655k | id stringlengths 47 47 | score float64 2.52 5.25 | tokens int64 39 148k | format stringclasses 24
values | topic stringclasses 2
values | fr_ease float64 -483.68 157 | __index__ int64 0 1.48M |
|---|---|---|---|---|---|---|---|
Show that the work required to assemble
four identical point charges of magnitude q on the corners of a square of
side a is
To calculate the work to assemble any number of point charges you can proceed as follows:
- Numerate each charge.
- Assume charges are brought from an infinite distance.
- Charge 1 is brought firs... | <urn:uuid:59d49671-1dc7-467d-a99c-99d4d19ba321> | 3.328125 | 1,081 | Tutorial | Science & Tech. | 75.260201 | 2,900 |
It is being said by the end of this year the underground South Dakota laboratory in the US will start collecting data with a good chance to discover dark matter.
Dark matter is an elusive matter known only by its gravitational pull and is so far undetected. By discovering dark matter, scientists could explain how the w... | <urn:uuid:f1d477f1-849c-40cf-a761-305972c6ed53> | 2.6875 | 95 | Truncated | Science & Tech. | 40.436429 | 2,901 |
Behind the buzz and beyond the hype:
Our Nanowerk-exclusive feature articles
Posted: Oct 19th, 2007
Fullerenes for hydrogen storage
(Nanowerk Spotlight) In our Spotlight on the issues of moving to hydrogen-powered cars (Nanotechnology could clean up the hydrogen car's dirty little secret) we briefly touched upon the pr... | <urn:uuid:1c427949-4643-4847-b9c7-ef91b3787764> | 3.15625 | 1,179 | Content Listing | Science & Tech. | 22.938056 | 2,902 |
I’ve found it difficult to find a guide for learning Backbone.js. They’re probably out there — but it isn’t easy. This is the first in a series of articles dedicated to giving a complete overview of Backbone.js through simple examples and concise code.
Something of a cookbook, you might say.
What you’ll need:
- Backbon... | <urn:uuid:36fb3da1-5d2e-4907-a566-5658b20d25c5> | 2.625 | 1,452 | Tutorial | Software Dev. | 60.412102 | 2,903 |
BY MICHELE S. BYERS
THE STATE WE'RE IN
After more than three centuries of repeated cutting for timber, firewood, charcoal and conversion to rocky pastures, the forests in New Jersey’s Highlands might get more interesting after the triple-whammy of Hurricane Irene, the 2011 Halloween snowstorm and Superstorm Sandy.
Heal... | <urn:uuid:7ae6b100-2753-4cea-a2c3-24af078dbf32> | 3.46875 | 962 | Nonfiction Writing | Science & Tech. | 36.791977 | 2,904 |
For some time, biologists have known that ecological communities made up of many species are particularly resistant to invasion by new species. The most obvious explanation is that the communities are stable because all the niches are filled and so there is no room for new species. But the obvious answer is wrong, acco... | <urn:uuid:bdd6927a-076d-4132-864b-cafe697879ab> | 3.25 | 204 | Truncated | Science & Tech. | 30.956434 | 2,905 |
We have been reading much about droughts, excessive rainfall and explanations of global warming, but another unpublicized factor enters the story of climatic change. Recall that several years ago an Icelandic volcano erupted and put so much ash into the sky that European air travel was disrupted for several days.
What ... | <urn:uuid:1f1b7be6-67b4-4cc6-b5b7-ce3674c54ed6> | 3.953125 | 372 | Nonfiction Writing | Science & Tech. | 54.915588 | 2,906 |
"Smart" phones offer the intelligence of a computer, with the convenience of a phone. "Smart" meters let homeowners choose between using cheap and expensive electricity.
More News From ClimateWire
- Obama Aides Meet With Senate Dems to Map April Strategy for Climate Bill
- The Quest for Cheap, Clean Power -- Science Tr... | <urn:uuid:1fa0ebbc-865f-4a83-a005-f152f3880807> | 2.65625 | 1,310 | News Article | Science & Tech. | 43.313388 | 2,907 |
MOSCOW Gym class came to a halt inside the Chelyabinsk Railway Institute, and students gathered around the window, gazing at the fat white contrail that arced its way across the morning sky. A missile? A comet? A few quiet moments passed. And then, with incredible force, the windows blew in.
The scenes from Chelyabinsk... | <urn:uuid:d3aa8133-5f32-471b-a8cd-3251b8f3250e> | 3 | 522 | News Article | Science & Tech. | 50.510749 | 2,908 |
Consider the polarity of the ions released when the water decomposed.
Which gas collected at the cathode? Why?
(Oxygen. Oxygen ions are positive and the cathode is negative.
were there more hydrogen bubbles than oxygen bubbles? (Water
contains twice as many hydrogen atoms as oxygen atoms.)
did the chlorine gas generate... | <urn:uuid:cd44f6e9-b78e-451f-ade5-0468937ffc20> | 3.59375 | 152 | Tutorial | Science & Tech. | 40.240559 | 2,909 |
The polar bear has become the poster child of global warming, but there’s more to the Arctic than ice and polar bears. Beyond these two famous and prominent features of the Arctic environment, there is an entire intricate ecosystem of wildlife and plant life that will be profoundly affected by a prolonged warming trend... | <urn:uuid:bbb2f7f8-cfb7-403e-a6cd-1e00bd64f464> | 3.984375 | 1,005 | Knowledge Article | Science & Tech. | 44.000857 | 2,910 |
libpq is the C application programmer's interface to PostgreSQL. libpq is a set of library routines that allow client programs to pass queries to the PostgreSQL backend server and to receive the results of these queries. libpq is also the underlying engine for several other PostgreSQL application interfaces, including ... | <urn:uuid:aaa06f7f-40ad-46e6-b44b-83912be1fd71> | 2.875 | 176 | Documentation | Software Dev. | 51.460938 | 2,911 |
A light bulb and a few chemicals: Scientists find a way to help make new reactions
Posted September 4, 2008; 02:00 p.m.
Princeton scientists have discovered a way of stimulating organic molecules that they expect will prompt researchers to create materials from new kinds of chemical reactions.
The method of catalysis, ... | <urn:uuid:4b4369ee-517d-4a0b-b331-9a53f77eb5c9> | 3.328125 | 973 | News Article | Science & Tech. | 26.179229 | 2,912 |
Greening Tomorrow: A Green New York
||Xsl file could not be processed: /xsl/flash_media_player.xslt
“Conservation globally includes conservation at home.”— Dr. Steven E. Sanderson, President & CEO of WCS
The Wildlife Conservation Society is dedicated to greening its own backyard with measures to combat climate change a... | <urn:uuid:455c719b-9838-49e5-abb6-e00b084a7de9> | 3.203125 | 540 | About (Org.) | Science & Tech. | 37.861272 | 2,913 |
The Office of Naval Research (ONR) is looking to the sun for energy in an effort to help Marines do away with diesel-guzzling generators now used in combat outposts, officials announced.
The Renewable Sustainable Expeditionary Power (RSEP) program seeks to create a transportable renewable hybrid system that can provide... | <urn:uuid:05876b08-c1cb-4ce1-9b86-ca5165709465> | 2.84375 | 674 | News Article | Science & Tech. | 31.884274 | 2,914 |
Get access to the common mistakes students make in their A-Level physics exams. Inspired by The Examiner's reports this is an un-missable opportunity to find out where precious marks are dropped.
The leaves are the part of a plant where most photosynthesis takes place.
If you cut a leaf in half and look at the cut end ... | <urn:uuid:27a34c90-02f1-4e8f-9574-9e155923fabd> | 4.09375 | 971 | Knowledge Article | Science & Tech. | 60.105938 | 2,915 |
How do Z pinches contribute to a variety of scientific research projects?
Z provides the fastest, most accurate, and cheapest method to determine how materials will react under high pressures and temperatures, characteristics that can then be expressed in formulas called “equations of state.” Equations of state tell re... | <urn:uuid:1c9cf1d1-d505-41d1-ac40-4ebd58a3e6fe> | 4 | 985 | Knowledge Article | Science & Tech. | 30.301988 | 2,916 |
July 28, 1997 Donald Savage Headquarters, Washington, DC July 23, 1997 (Phone: 202/358-1547)
Lynn Jenner Goddard Space Flight Center, Greenbelt, MD (Phone: 301/286-0454)
ADVANCED COMPOSITION EXPLORER SET TO STUDY MATTER FROM SUN, MILKY WAY AND BEYOND
The Earth is constantly being bombarded by a stream of accelerated pa... | <urn:uuid:28db26e5-aa12-4dee-a89a-291c25377b57> | 3 | 1,044 | News Article | Science & Tech. | 31.971545 | 2,917 |
May 14, 2012 Amber from Cretaceous deposits (110-105 my) in Northern Spain has revealed the first ever record of insect pollination. Scientists have discovered in two pieces of amber several specimens of tiny insects covered with pollen grains, revealing the first record of pollen transport and social behavior in this ... | <urn:uuid:19c494cf-aca7-41e8-bbc0-9c2085e84c86> | 4 | 1,024 | News (Org.) | Science & Tech. | 38.000872 | 2,918 |
Discover one of our 28 local entrepreneurial communities »
Be the first to know as we launch in new countries and markets around the globe.
Interested in bringing MIT Technology Review to your local market?
Unsupported browser: Your browser does not meet modern web standards. See how it scores »
The collision of virtua... | <urn:uuid:b51f0358-d4cf-46b2-a23d-16a5573be887> | 2.53125 | 245 | Content Listing | Science & Tech. | 41.396591 | 2,919 |
Want to stay on top of all the space news? Follow @universetoday on Twitter
A new paper out today reports that the Voyager 1 spacecraft appears to have traveled beyond the influence of the Sun and exited the heliosphere. However, the data they cite is the same as what NASA Voyager scientists claimed in December 2012 wa... | <urn:uuid:ccaeff3f-dca9-4b10-b0b7-aa041019ce46> | 2.9375 | 1,000 | News Article | Science & Tech. | 42.407451 | 2,920 |
This document has the following sections:
What is an Indexer?
Goal of an indexer
The main goal of an indexer is to create and setup some resource
automatically. The resources can be created depending on their
name or their extension. Once the resource has been created, the
indexer is also in charge of attaching the rig... | <urn:uuid:a8f70524-9f68-4fbf-8df3-b1e0cb52d1bc> | 2.78125 | 757 | Documentation | Software Dev. | 45.149485 | 2,921 |
HTML 4.0 (the predecessor of 4.01) introduced something called frames, which split the browser's viewport up into different sections, each displaying a different webpage.
It was a good idea in concept, but the execution left a few things to be desired. Amongst the litany of woes:
Using the back button on a browser in f... | <urn:uuid:f15693ab-521a-48d7-b149-f9c82782f321> | 2.953125 | 700 | Comment Section | Software Dev. | 56.87876 | 2,922 |
Nicotinamide adenine dinucleotide phosphate
|Nicotinamide adenine dinucleotide phosphate|
| Except where noted otherwise, data are given for|
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references
In chloroplasts, NADP is reduced by ferredoxin-NADP+ reductase in last step of the electro... | <urn:uuid:2c16cd45-5306-433b-bee7-289606daf140> | 2.8125 | 239 | Knowledge Article | Science & Tech. | 1.8285 | 2,923 |
METR 101 Introduction to the Weather • 5 Cr.
Introduces the study of the weather, including atmospheric properties and processes that control temperature, wind, precipitation, and storm systems. Students also discuss weather forecasting, air pollution, and climate change. Format may include field trips and guest lectur... | <urn:uuid:777f159f-8d5b-42a4-8a52-f8c391d83434> | 3.84375 | 648 | Product Page | Science & Tech. | -22.390556 | 2,924 |
The Power of the Solar Arrays
Recently, one of our fans on the NASAJPL Facebook page asked a good question about the efficiency of solar arrays on the Dawn and Rosetta spacecraft.
“A question about Dr. Marc D. Rayman’s comment in his Dawn journal, saying that ‘its tremendous solar arrays [are] the most powerful ever us... | <urn:uuid:22ac592d-a0d2-4c12-a619-960e6bed945a> | 3.78125 | 956 | News (Org.) | Science & Tech. | 48.843387 | 2,925 |
The Chemical Abstracts Service
is part of the American Chemical Society
and maintains a database of chemical compounds and sequences. The CAS database currently contains over 55 million different organic and inorganic chemical compounds. Each CAS entry is identified by their CAS Registry Number, or CAS RN for short.
CA... | <urn:uuid:805c1377-d92d-49a3-a40e-cf01f2de3b76> | 3.375 | 272 | Knowledge Article | Science & Tech. | 52.089914 | 2,926 |
Volume 12, Number 22: 3 June 2009
There is considerable current concern that the ongoing rise in the air's CO2 content is causing a significant drop in the pH of the world's oceans in response to their absorption of a large fraction of each year's anthropogenic CO2 emissions. It has been estimated, for example, that th... | <urn:uuid:c618a618-883c-40f2-a2a4-1f47b3b9c147> | 3.3125 | 1,406 | Knowledge Article | Science & Tech. | 57.935356 | 2,927 |
The codecs defines a set of base classes which define the interface and can also be used to easily write you own codecs for use in Python.
Each codec has to define four interfaces to make it usable as codec in Python: stateless encoder, stateless decoder, stream reader and stream writer. The stream reader and writers t... | <urn:uuid:b49e9300-7a5b-4564-b569-8f045480a69e> | 3.625 | 211 | Documentation | Software Dev. | 26.880849 | 2,928 |
This module provides regular expression matching operations similar to
those found in Perl. Regular expression pattern strings may not
contain null bytes, but can specify the null byte using the
\number notation. Both patterns and strings to be
searched can be Unicode strings as well as 8-bit strings. The
re module is ... | <urn:uuid:9d8eae3e-d2bc-470b-b1ac-bc0791fa2ede> | 2.765625 | 267 | Documentation | Software Dev. | 39.354013 | 2,929 |
Special & General Relativity Questions and Answers
Does anyone really understand general relativity well enough to have an intuitive grasp of the universe?
It is all a mater of perspective. Physicists and astronomers who spend all of their professional lives amass an enormous amount of intuition about the mathematics o... | <urn:uuid:c11a9cb5-3054-43d9-b693-7329c165494e> | 2.875 | 284 | Q&A Forum | Science & Tech. | 26.640448 | 2,930 |
|Navigate Language Fundamentals topic:)|
The previous chapter "Getting started" was a primer course in the basic of understanding how Java programming works. Throughout the chapter, we tackled with a variety of concepts that included:
- Objects and class definitions;
- Abstract and data types;
- Class-level and method-... | <urn:uuid:11f2776d-fdd2-4921-9709-187c87581a3d> | 4.15625 | 357 | Truncated | Software Dev. | 32.581113 | 2,931 |
The first law is concerned with the internal energy change of a system. This is what ΔU represents. As I admitted earlier U is an odd concept to me. I think this primarily arises because, at least chemically speaking, we're mostly interested in the changes in U. Changes in energy I am comfortable with, and the way in w... | <urn:uuid:cd1672d8-ba77-40b8-84be-e06297dd17b8> | 3.109375 | 1,393 | Personal Blog | Science & Tech. | 49.209054 | 2,932 |
On this coming Sunday June 30, intrepid horologists from around the world will daringly attempt to hold back the relentless onslaught of time. Well, to be fair it won't actually be that difficult. July 1st is scheduled to start an entire second later than it should, a feat of temporal distortion that will be accomplish... | <urn:uuid:7a411b90-1884-4336-9da7-88651f1a51f5> | 2.75 | 490 | News Article | Science & Tech. | 52.922385 | 2,933 |
Bill intensifies to Category 4; globe has 5th warmest July on record
Category 4 Hurricane Bill is now the the fourth strongest tropical cyclone to appear on the planet so far this year, and may grow even stronger. Visible and infrared satellite imagery continue to show an impressive, well-organized, hurricane, with ple... | <urn:uuid:87f0a8db-a39e-4ab4-9be0-515d2225f068> | 2.796875 | 1,783 | Personal Blog | Science & Tech. | 59.782016 | 2,934 |
"The Processing language was originally created at MIT as part of the Media lab and Aesthetics and Computation group. They needed a way to bridge the gap between software developers, artists, data visualizers, etc., and to do so in a way that allowed new programmers (or non-programmers) to do complex visual work easily... | <urn:uuid:1040756c-e596-43cc-bd11-6c4f33b702a8> | 2.953125 | 233 | Personal Blog | Software Dev. | 51.843896 | 2,935 |
Manual Section... (3) - page: expl
NAMEexp, expf, expl - base-e exponential function
#include <math.h> double exp(double x);
float expf(float x);
long double expl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
DESCRIPTIONThe exp() function returns the value of e (... | <urn:uuid:08b1d23f-04d4-4815-ae68-00afd0496673> | 2.75 | 430 | Documentation | Software Dev. | 65.208796 | 2,936 |
The magnetic and electric fields are force fields. They exert forces on magnetic or charged particles. We can measure these fields easily with instruments that respond to such forces. Magnetic and electric fields therefore have a very real and tangible existence. But these force fields themselves are merely higher orde... | <urn:uuid:874613ab-5a67-44d2-a2f6-45c09ccf1bdb> | 4.125 | 1,397 | Academic Writing | Science & Tech. | 33.025924 | 2,937 |
By Jonathan Fildes
Science and technology reporter, BBC News
The first thing that hits you when you enter Professor Takamichi Nakamoto's laboratory is the smell.
An odour recorder could be used in the fragrance industry
Wafts of fried beef and onions, the rich smell of Japanese curry and even the obnoxious smell of rot... | <urn:uuid:916f8456-8e14-43b8-99e6-771ca32253a0> | 2.84375 | 987 | News Article | Science & Tech. | 38.846231 | 2,938 |
Earlier today, scientists at the European Space Agency marked a milestone: On March 1, 2002, the largest Earth observation satellite ever built was launched into orbit. During the course of its (extended) lifetime, the Envisat satellite has circled the Earth more than 50,000 times, providing fodder to scientists publis... | <urn:uuid:51e1d7b5-d6f2-4488-aa53-8ea53d49cc5e> | 3.125 | 182 | Truncated | Science & Tech. | 33.941164 | 2,939 |
When the groundhog named Punxsutawney Phil was pulled from his fake tree trunk in Pennsylvania on February 2, he saw his shadow. According to legend, that means the winter blues are sticking around.
So, what's the good news?
According to John Hanson Mitchell, an editor with the Massachusetts Audubon Society in Lincoln ... | <urn:uuid:0e1acd83-c31b-4909-96bd-bb20925ef8c7> | 2.96875 | 515 | News Article | Science & Tech. | 52.660287 | 2,940 |
FFI photo by Zhao Chao
“With only about 100 cao vit gibbons remaining in the world, the recent birth of this baby has extra significance,” Fauna & Flora International said today.
“This species is only found in one location in the world, on the international border between Vietnam and China,” the UK-based conservation c... | <urn:uuid:b7b2558d-4c58-4002-b189-689d932e8e07> | 3.09375 | 790 | News Article | Science & Tech. | 37.4825 | 2,941 |
The reversibility of sea ice loss in a state-of-the-art climate model
Article first published online: 20 AUG 2011
Copyright 2011 by the American Geophysical Union.
Geophysical Research Letters
Volume 38, Issue 16, August 2011
How to Cite
2011), The reversibility of sea ice loss in a state-of-the-art climate model, Geop... | <urn:uuid:7ab03b45-38ad-498e-a05d-d1195ef91754> | 2.625 | 417 | Academic Writing | Science & Tech. | 28.986638 | 2,942 |
Suppose you have to specify the moment in time when a given event occurred, a "zero time". The record must be accurate to the minute, and be obtainable even after thousands of years. All the measures of time we currently have are relative to a well defined zero, but the zero is not easy to backtrack exactly.
One possib... | <urn:uuid:ac094f67-9815-4f22-8c94-cf5cc20e575a> | 3.15625 | 239 | Q&A Forum | Science & Tech. | 45.4335 | 2,943 |
Plus MagazineIssue 2
Find out how modern telephone networks use mathematics to make it possible for a person to dial a friend in another country just as easily as if they were in the same street, or to read web pages that are on a computer in another continent.
The mathematics underlying today's complex telephone netwo... | <urn:uuid:191b7f50-b479-4151-afd8-1a930ef3733c> | 3.421875 | 259 | Truncated | Science & Tech. | 45.783726 | 2,944 |
Possible applications for solar cells and other small-scale circuits
SAN DIEGO, CA -- Learning how to control the movement of electrons on the molecular and nanometer scales could help scientists devise small-scale circuits for a wide variety of applications, including more efficient ways of storing and using solar ene... | <urn:uuid:b75d188e-89c7-4f04-816d-e6ae675a0cee> | 2.90625 | 694 | News Article | Science & Tech. | 28.650385 | 2,945 |
It's staggering to imagine a time when the Earth and its planetary siblings were nothing but cosmic dust. Yet astronomers agree that this was the state of things some 4.5 billion years ago. Our sun was but a fledgling protostar, continually amassing more matter via gravity and steadily cranking up its internal nuclear ... | <urn:uuid:e7c5ba70-25f4-44d8-a074-b668cd00bc95> | 4.34375 | 504 | Knowledge Article | Science & Tech. | 47.321515 | 2,946 |
Deep Seas, Dark Worlds
There's barely enough room for three people to fit. But marine scientists Richard Lutz and Peter Rona of Rutgers University crammed themselves into Alvin, a tiny submersible vehicle made for exploring the deep seafloor. Unlike scientists who boarded Alvin before them, Lutz and Rona weren't going ... | <urn:uuid:26904a0c-5ab1-40b6-b827-96508b347fca> | 3.125 | 1,445 | Knowledge Article | Science & Tech. | 50.600671 | 2,947 |
A simple way to think of mixins is as “an interface with implementation”. If you have written Java interfaces, you have surely found yourself writing the same implementations over and over for each class that implements the interface. A mixin lets you write the implementation once and have it automatically included in ... | <urn:uuid:c184734a-5a17-4090-9912-8936e6ba687c> | 2.671875 | 955 | Knowledge Article | Software Dev. | 46.086174 | 2,948 |
Do you like frogs? Many kids love to see these tiny creatures hopping around the backyard or a local pond. They’re even fun to catch and keep as a pet. One of the most interesting things about frogs, though, is how they begin their lives.
A mother frog doesn’t give birth to a live baby frog that looks like a miniature ... | <urn:uuid:35de440a-f826-4e7d-a9e0-c3f3d049eabf> | 3.578125 | 459 | Knowledge Article | Science & Tech. | 60.18731 | 2,949 |
Nuclear Power in the World Today
(updated April 2012)
- The first commercial nuclear power stations started operation in the 1950s.
- There are now over 430 commercial nuclear power reactors operating in 31 countries, with 372,000 MWe of total capacity.
- They provide about 13.5% of the world's electricity as continuou... | <urn:uuid:486837de-75b8-4002-b5a4-6aac53a09e78> | 3.453125 | 1,212 | Knowledge Article | Science & Tech. | 47.325606 | 2,950 |
Scientists Explore Dramatic Changes Expected from Nanofabrication
A trio of top scientists predicted that nanofabrication in the decades ahead could have an array of uses in daily life, from the development of molecular electronics and optics to the creation of artificial muscles.
During an online cyberchat sponsored b... | <urn:uuid:0d983e10-8770-4a9d-a37b-9b4bceeb4eb8> | 3.21875 | 952 | News (Org.) | Science & Tech. | 13.479268 | 2,951 |
Science subject and location tags
Articles, documents and multimedia from ABC Science
Friday, 24 May 2013
Citizen scientists have helped solve a decades-old puzzle by assisting astronomers to make the most accurate distance measurements yet for an important star system.
Monday, 25 March 2013
Unnecessary use of antibiot... | <urn:uuid:812f9384-c3e1-4d07-a5e8-521022daa294> | 2.8125 | 503 | Content Listing | Science & Tech. | 34.918533 | 2,952 |
Science Fair Project Encyclopedia
Artificial life, also known as alife or a-life, is the study of life through the use of human-made analogs of living systems. Computer scientist Christopher Langton coined the term in the late 1980s when he held the first "International Conference on the Synthesis and Simulation of Liv... | <urn:uuid:ded0c78a-965d-4595-a118-4afb5e76430a> | 3.28125 | 2,544 | Knowledge Article | Science & Tech. | 25.42966 | 2,953 |
22 October 2010
Source: Science Centric
International marine scientists say that a huge coral death which has struck Southeast Asian and Indian Ocean reefs over recent months has highlighted the urgency of controlling global carbon emissions.
Many reefs are dead or dying across the Indian Ocean and into the Coral Trian... | <urn:uuid:2c0d3e9f-2bac-400e-bef9-eea7a95e3f8e> | 3.46875 | 825 | News Article | Science & Tech. | 37.948684 | 2,954 |
The Bahamas Biocomplexity Project is divided into five main working groups in order to tackle various research components. Most of these efforts are designed to intersect to enable interdisciplinary analyses in later stages of the project. In addition to these working groups there are several organizations that meet pe... | <urn:uuid:2b08fc05-33a1-4b66-9053-c9cf33b4c9cb> | 3.015625 | 2,126 | About (Org.) | Science & Tech. | 5.0302 | 2,955 |
Samples from Tranquility Base suggest solar wind brings water to lunar soil. Photo Credit: NASA
The solar wind is a likely contributor to widespread surface level water deposits in lunar soil churned by micrometeoroid impacts over billions of years, according to an analysis of tiny glass-like features called agglutinat... | <urn:uuid:10d8571f-7a1f-4532-a65e-075c39cab399> | 3.640625 | 578 | News Article | Science & Tech. | 13.938179 | 2,956 |
Simply begin typing or use the editing tools above to add to this article.
Once you are finished and click submit, your modifications will be sent to our editors for review.
...the stream). The processing and transport of essential elements follow a downstream sequence. Hypotheses attempting to explain ecological proce... | <urn:uuid:ee48c410-9bbd-47b9-ae4c-f26c682ae4a4> | 2.828125 | 120 | Truncated | Science & Tech. | 40.174333 | 2,957 |
In the science news this week, a journey across Antarctica during the winter is announced, first nuclear fusion reactor built, the mystery behind the killer whales’ menopause may have been solved, and finally… Google launches new Easter Egg feature.
Sir Ranulph Fiennes announces latest record attempt
Explorer Sir Ranul... | <urn:uuid:85f5d397-7596-4191-a70a-8e83d540a4d4> | 2.71875 | 1,870 | Content Listing | Science & Tech. | 49.942796 | 2,958 |
Common Lisp the Language, 2nd Edition
Time is represented in three different ways in Common Lisp: Decoded Time, Universal Time, and Internal Time. The first two representations are used primarily to represent calendar time and are precise only to one second. Internal Time is used primarily to represent measurements of ... | <urn:uuid:b8251ed7-0cac-46e4-8c26-97b3b07b507c> | 3.640625 | 1,137 | Documentation | Software Dev. | 35.338803 | 2,959 |
Theories about how black holes are grown inside a galaxy may have to be modified because of a recent discovery astronomers made using UT’s Hobby-Eberly Telescope.
While working on a study to better understand how galaxies grow and form together, astronomers discovered a massive black hole with a size relative to its ga... | <urn:uuid:feaf4e82-6a87-472e-b18c-b496780755bd> | 4.21875 | 508 | News Article | Science & Tech. | 58.914502 | 2,960 |
Vast amounts of methane hydrates are stored in sediments along the continental margins. Their stability is due to the low temperature–high-pressure conditions found on the seafloor. Global warming could destabilize these hydrates and cause a release of methane (CH4) into the water column and possibly the atmosphere.
Se... | <urn:uuid:5c869535-feca-424c-86c8-afb0b90fec71> | 3.421875 | 458 | Academic Writing | Science & Tech. | 45.39528 | 2,961 |
DNA is tightly packed in the nucleus of every cell. DNA wraps around special proteins called histones, which form loops of DNA called nucleosomes. These nucleosomes coil and stack together to form fibers called chromatin. Chromatin in turn forms larger loops and coils to form chromosomes.
1 minute 43 seconds
Play Large... | <urn:uuid:3ec4b7c2-8bf6-4f2b-b8d5-01cbddd09660> | 2.875 | 134 | Truncated | Science & Tech. | 74.541951 | 2,962 |
Now scientists have found a clever way to save the endangered quoll: training it to detest the taste of toad so it won't get poisoned.
Brought to Queensland state in 1935 to control beetles in sugar cane fields, the cane toad is one of many Old World animals to wreak havoc on Australia's native ecosystem.
Unlike most i... | <urn:uuid:d25d2493-1886-4222-9c31-9a2ce559bb84> | 3.671875 | 720 | News Article | Science & Tech. | 47.797034 | 2,963 |
The following HTML text is provided to enhance online
readability. Many aspects of typography translate only awkwardly to HTML.
Please use the page image
as the authoritative form to ensure accuracy.
In the Light of Evolution: Volume II—Biodiversity and Extinction
these activities increase the level of awareness and th... | <urn:uuid:6a0cb827-a2f2-45d8-b17c-d5ed5bbd6302> | 2.734375 | 537 | Knowledge Article | Science & Tech. | 19.584673 | 2,964 |
Get flash to fully experience Pearltrees
Design patterns are solutions to software design problems you find again and again in real-world application development. Patterns are about reusable designs and interactions of objects.. The 23 Gang of Four (GoF) patterns are generally considered the foundation for all other pa... | <urn:uuid:da22a956-d8ca-4419-a126-9f9c5c9ba934> | 2.9375 | 157 | Product Page | Software Dev. | 24.176512 | 2,965 |
|Jan3-13, 05:44 PM||#1|
I thought of this question the other day, and I was unable to solve it. A Google search has not helped, so I thought I might post it here.
A point mass hangs from a rod of length "l" from the center of a pendulum. The only forces acting upon the point mass are the force of gravity and the force ... | <urn:uuid:aacc4074-9ee6-4243-a7a4-8a3c803b8c48> | 2.6875 | 469 | Comment Section | Science & Tech. | 69.410204 | 2,966 |
Some unknown terrible person shot a defenseless pilot whale last month, leaving it to swim the Atlantic in agony for weeks before it finally beached itself on the New Jersey shore and died. Authorities are still looking for the shooter. The bullet wound caused a fulminant infection in the whale’s jaw that prevented it ... | <urn:uuid:b6502306-e434-43de-977a-97e28d1218d6> | 2.828125 | 1,058 | News Article | Science & Tech. | 50.601387 | 2,967 |
Jan. 1, 2001 NASA's Cassini spacecraft, which made its closest approach to Jupiter early today, is providing ways to make invisible features visible, to track daily changes in some of the planet's most visible storms, and to hear the patterns in natural radio emissions near the edge of Jupiter's magnetic environment.
I... | <urn:uuid:080fc1bd-c136-4cb5-8db5-f082fef8b3a3> | 4.09375 | 920 | News Article | Science & Tech. | 39.364742 | 2,968 |
May 14, 2007 With meteorologists concerned about a possible worldwide intensification of tornado activity, scientists in Germany are proposing a new approach to studying formation of twisters, which pack Earth's most violent winds. It involves forming microtornadoes under millimeter-scale crystalline "igloos," accordin... | <urn:uuid:0f23ec25-5d6e-43ab-b07b-e97202233c8d> | 3.75 | 371 | News Article | Science & Tech. | 16.473117 | 2,969 |
Aug. 10, 2011 A team of scientists just discovered a new eruption of Axial Seamount, an undersea volcano located about 250 miles off the Oregon coast -- and one of the most active and intensely studied seamounts in the world.
What makes the event so intriguing is that the scientists had forecast the eruption starting f... | <urn:uuid:a716199e-c5c2-4ef0-b317-9491ed0dc038> | 3.765625 | 1,596 | News Article | Science & Tech. | 40.696938 | 2,970 |
Narrator: This is Science Today. A new air sampler, which can effectively trap and evaluate fine particle pollutants in both their solid and gas phases has been developed by scientist Lara Gundel of the Lawrence Berkeley National Laboratory. This sampler can greatly impact future EPA air quality standards and lead to a... | <urn:uuid:8a346dd2-3a3a-47c9-99e2-26e162d036a7> | 3.484375 | 235 | Audio Transcript | Science & Tech. | 25.4825 | 2,971 |
Narrator: This is Science Today. One of five nanoscale science research centers funded by the Department of Energy is located at the Lawrence Berkeley National Laboratory. Rick Kelly, the Environmental Health and Safety Manager of the Molecular Foundry, explains the intent of the facility is to foster the development o... | <urn:uuid:7c399043-75f4-4b7c-b080-b673d0d7e541> | 2.703125 | 258 | Audio Transcript | Science & Tech. | 21.82 | 2,972 |
Journal of Heterocyclic Chemistry
Overview. A heterocyclic compound is defined as any organic compound where their molecules are characterized by rings containing at least one atom other than carbon. These compounds are structurally similar to cyclic organic hydrocarbons, but their properties can vary widely from those... | <urn:uuid:f95c76cf-0c21-4929-bc98-2c5aadc40ed3> | 3.203125 | 768 | Knowledge Article | Science & Tech. | 10.14375 | 2,973 |
Enzymatic Reaction (image will open in a new window)
Polyphenol oxidase (tyrosinase) (TY) is a bifunctional, copper-containing oxidase having both catecholase and cresolase activity (Malmström and Rydén 1968):
Jolley et al. (1974) refer to it as an oxygen and 4 electron-transferring phenol oxidase. It is responsible fo... | <urn:uuid:04a0f9ec-7add-4fb7-b162-087b544f4c2e> | 2.828125 | 628 | Knowledge Article | Science & Tech. | 38.642063 | 2,974 |
Synchrotron radiation occurs when a charge moving at relativistic speeds follows a curved trajectory. In this section, formulas and supporting graphs are used to quantitatively describe characteristics of this radiation for the cases of circular motion (bending magnets) and sinusoidal motion (periodic magnetic structur... | <urn:uuid:4ace650b-f9a9-4a69-b1d3-dc8fbca78e59> | 4.125 | 3,070 | Academic Writing | Science & Tech. | 58.562295 | 2,975 |
Entire Sea Floor, Food Chain Face Shakeup, Fossil Data Suggests
There’s more worrying news out today about the health of the world’s oceans, with an Australian paleontologist — using the largest-ever sampling of fossil data – concluding the Earth is facing a mass extinction larger than even the end of the dinosaur age.... | <urn:uuid:3b59909d-b3f4-4382-8758-7e910c3e8819> | 3.109375 | 1,008 | News Article | Science & Tech. | 40.306454 | 2,976 |
According to Real Climate
, it's extremely unlikely for that to happen:
Could there be a methane runaway feedback?.
The “runaway greenhouse effect” that planetary scientists and climatologists usually call by that name involves water vapor. A runaway greenhouse effect involving methane release (such as invoked here) is... | <urn:uuid:c1cf679c-e4f0-4d25-96a4-c19981f8bf13> | 3.625 | 715 | Comment Section | Science & Tech. | 38.017242 | 2,977 |
Did you know that Hook Grasses can control water loss by folding up their leaves?
Contrary to their common name, Hook Grasses are not grasses but Sedges and they belong to the family Cyperaceae. Sedges are commonly found in wet or poorly drained habitats. Hook Grasses, however, can be found in a much greater diversity ... | <urn:uuid:8f2159a5-e882-4c5c-bd5a-4266cda1bcea> | 3.984375 | 274 | Knowledge Article | Science & Tech. | 46.821433 | 2,978 |
Talk about a long trip. An exploding star‘s burst of light traveled 13 billion years, from the early days of the universe to the present day, before being detected by astronomers here on Earth. Researchers say this exploding star is the most distant blast ever seen.
The light from the distant explosion, called a gamma-... | <urn:uuid:5ce184cf-3787-4d67-8e94-a8ddeb29adcd> | 3.9375 | 436 | News Article | Science & Tech. | 45.749532 | 2,979 |
The atlas of climate change: mapping the world's greatest challenge
University of California Press
, 2007 - Science
- 112 pages
Today's headlines and recent events reflect the gravity of climate change. Heat waves, droughts, and floods are bringing death to vulnerable populations, destroying livelihoods, and driving pe... | <urn:uuid:28c4b9cd-3a36-4bc3-8eec-b16faeb61b8e> | 3.125 | 224 | Product Page | Science & Tech. | 3.229698 | 2,980 |
Next: Lu and Torquato Up: Lognormally Distributed Spheres Previous: Pleau and Pigeon
The equation for G given in Eqn. 13 for the sphere distribution of Eqn. 11 can also be used to approximate the correct value of G for the zeroth-order logarithmic distribution used here. The parameters a and b in Eqn. 11 are chosen to ... | <urn:uuid:b60987c1-f0ec-4555-be24-6f7c1f15038a> | 2.96875 | 491 | Academic Writing | Science & Tech. | 45.994467 | 2,981 |
[Source: National Space Science Data Center, http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1999-067A
MSP F15 (USA 147) was launched by a Titan rocket from Vandenberg AFB on December 12, ... 1999 into a 101 minute, sun-synchronous near-polar orbit at an altitude of 840km and with the Local Time nodes of 21:10 a... | <urn:uuid:25d4dc5b-e319-486e-ab92-31c37b82cccc> | 3.015625 | 355 | Knowledge Article | Science & Tech. | 50.951083 | 2,982 |
Fisher Science Education, through a partnership with Beyond Benign, developed this classroom ready slide presentation that briefly describes the 12 principles of green chemistry. The presentation first focuses on the role of chemists in society and introduces green chemistry as a way to solve environmental problems. Ea... | <urn:uuid:58228af0-e824-44d1-aaac-c341a6c94cc6> | 3.71875 | 135 | Content Listing | Science & Tech. | 37.492652 | 2,983 |
Compaq Fortran record structures are similar to Fortran 95/90 derived types.
A record structure is an aggregate entity containing one or more elements. (Record elements are also called fields or components.) You can use records when you need to declare and operate on multi-field data structures in your programs.
Creati... | <urn:uuid:35f387e4-869b-4210-bd4f-8372304a0dfd> | 2.59375 | 91 | Documentation | Software Dev. | 45.880505 | 2,984 |
|Portability||portable (depends on GHC)|
A set of rectangles describing areas to be redrawn.
- Regions consist of a set of non-overlapping rectangles. They are used to specify the area of a window which needs updating.
- makeNewRegion :: Ptr Region -> IO Region
- newtype Region = Region (ForeignPtr Region)
- regionNew ... | <urn:uuid:1e27d024-6464-4313-b861-3a25b91a8169> | 3.546875 | 411 | Documentation | Software Dev. | 14.119818 | 2,985 |
Derived Types: PolygonB, PolygonN
An abstract class that serves as a base to its derived types, representing a collection of one or more exterior and interior rings. .
The rings do not need to be connected to or
contained by other rings in the polygon. However,
all rings are considered to be part of a single polygon re... | <urn:uuid:2a9b0100-8b02-4c5e-a1ee-2394f85f5eaa> | 3.203125 | 228 | Documentation | Software Dev. | 34.993601 | 2,986 |
To examine the way the universe behaved in the past, astronomers look at extremely distant objects, such as supernovae in galaxies billions of light-years away. But how does that work? How can astronomers look out into space and see the universe back in time?
The answer lies in the speed of light. Light waves move very... | <urn:uuid:a1a817e7-4fd6-413b-8cc3-7719d3ca4e1b> | 4.1875 | 701 | Knowledge Article | Science & Tech. | 60.524366 | 2,987 |
On the beaches of Southern California, a phytoplankton called Lingulodinium polyedrum is responsible for a spate of red tide. Massive algal blooms like this make the water ruddy during the day, but disrupting the microorganisms at night results in bursts of electric blue bioluminescence. Says Scripps Institution of Oce... | <urn:uuid:a3e09f9e-72e2-4507-a78a-5d10f50d20a7> | 3.03125 | 206 | News Article | Science & Tech. | 38.345625 | 2,988 |
Optogenetics, a brand new field of research in which living, cortical neurons and other cells can be manipulated or controlled with optical technology (namely fiber optic cables), has been heralded as the next big thing for treating such things as heart conditions, paralysis, and even diabetes.
Up until now, however, t... | <urn:uuid:468141bd-1cc8-4ece-a026-e2d012aea4ee> | 3.40625 | 546 | Truncated | Science & Tech. | 28.854286 | 2,989 |
Main navigation | Main content
Islands in the Sun is a four-year research project funded by the University of Minnesota’s INSTITUTE ON THE ENVIRONMENT and the College of Food, Agricultural, and Natural Resource Sciences to monitor the urban heat island of the Twin Cities Metropolitan Area. The project aims to improve u... | <urn:uuid:d1e881a9-4263-40d9-a5a8-24c965bbfc66> | 3.078125 | 218 | News (Org.) | Science & Tech. | 26.834579 | 2,990 |
If we make the right decisions now about how to adapt to climate change, we can restore and even enhance biodiversity, says Robert Watson.
When biodiversity is mentioned in the context of climate change, it is usually in reference to the devastating effect that our changing climate will have on the species that make up... | <urn:uuid:37f17c4a-dc93-4409-9ba2-684d54ac583a> | 3.640625 | 1,070 | Nonfiction Writing | Science & Tech. | 23.564843 | 2,991 |
Please keep in mind that this is a research project, and there may
sometimes be glitches with the interactive software. Please
let us know of any
problems you encounter, and include the computer operating system,
the browser and version you're using, and what kind of connection
you have (dial-up modem, T1, cable).
When... | <urn:uuid:a2cad3f8-fd14-4334-9514-fda5c1606010> | 3.90625 | 397 | Tutorial | Science & Tech. | 68.963202 | 2,992 |
The topics in this section discuss the creation and management of managed threads, how to pass data to managed threads and get results back, and how to destroy threads and handle a ThreadAbortException.
Discusses and demonstrates the creation of managed threads, including how to pass data to new threads and how to get ... | <urn:uuid:af9adcd3-a641-4ba2-b214-d3a0aa6f620f> | 2.625 | 188 | Documentation | Software Dev. | 29.62 | 2,993 |
Who hasn’t dreamed of time travel, going back in time and saying the right thing instead of the wrong thing, seeing Lincoln give the Gettysburg address—or buying Apple stock when it was $10 a share? Many a science fiction novel and TV show are premised on just that possibility, and we happily suspend disbelief, at leas... | <urn:uuid:daf683e8-1517-4bf6-8abe-92bd37d0fdee> | 2.75 | 1,509 | Nonfiction Writing | Science & Tech. | 48.933964 | 2,994 |
Annual rings are acclaimed in representing natural climate archives. For the temperate latitudes it is known that the growth of these annual rings depend mainly on temperature and precipitation. In the tropics, however, with only slight seasonal variations, the correlation is not so evident. Now scientists of the GFZ G... | <urn:uuid:1c291ca8-e2b4-4d7d-933e-67c2ec3765be> | 3.140625 | 435 | News Article | Science & Tech. | 14.660402 | 2,995 |
If you've never heard of cubic Hamiltonian graphs before then take a look at Christopher Manning's wonderful cubic Hamiltonian graph builder. No, really, do! We too had never heard of them and now we think they are the bee's knees!
But what is a cubic Hamiltonian graph, you ask? A graph, of course, is just a bunch of p... | <urn:uuid:05126c7c-6e1a-4402-af1f-ae4f2fd871af> | 3.375 | 649 | Knowledge Article | Science & Tech. | 64.951886 | 2,996 |
Once again, x has gone missing. Help us find him!
Join us for an evening of math and learning. There’ll be spheres and equations and integrals, (oh my!). We’re open to anyone looking to brush up on basic skills and to those who want to learn a bit about advanced topics. We’ll be talking about set theory, topology, line... | <urn:uuid:3f388deb-6aa7-40c3-aaef-3c16330104ae> | 2.796875 | 445 | About (Org.) | Science & Tech. | 68.912612 | 2,997 |
Do cows pollute as much as cars?
Agriculture is responsible for an estimated 14 percent of the world's greenhouse gases. A significant portion of these emissions come from methane, which, in terms of its contribution to global warming, is 23 times more powerful than carbon dioxide. The U.S. Food and Agriculture Organiz... | <urn:uuid:e8ea9066-dc05-414c-8722-83a03d3bf0e8> | 3.28125 | 748 | Knowledge Article | Science & Tech. | 46.385065 | 2,998 |
Maybe there were vast oceans, and maybe they were occupied by microbes. This, according to reserearch being discussed in Natoial Geographic.
A vast ocean chock-full of microbes may have once covered more than a third of Mars’s surface, scientists say.
The new evidence, from an analysis of dried-up Mars river deltas, ad... | <urn:uuid:f59b36aa-5aff-48cc-b0c4-2b343bd4d983> | 3.53125 | 134 | News Article | Science & Tech. | 50.238824 | 2,999 |