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Martin Burrett

BBC - Acids, bases and metals - 81 views

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    A great animated and interactive science presentation from the BBC about acids, bases and metals. http://ictmagic.wikispaces.com/science
Deborah Batzer

The Comic Book Periodic Table of the Elements - 177 views

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    This site contains comic book images linked to the chemical elements via the periodic table. Comics include Uncle $crooge, Metal Men, Metamorpho, Batman, Fantastic Four, Superman, and many more."> The Comic Book Periodic Table of the Elements BODY { color: rgb(0,0,0);} Th
anonymous

The Effects Of The California Gold Rush - 22 views

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    The Effects Of The California Gold Rush California was rich in resources, minerals and metals. When America bought California from Mexico after the American Mexican War, the
Jac Londe

Physicists uncover novel phase of matter - 22 views

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    A team of physicists led by Caltech's David Hsieh has discovered an unusual form of matter-not a conventional metal, insulator, or magnet, for example, but something entirely different. This phase, characterized by an unusual ordering of electrons, offers possibilities for new electronic device functionalities and could hold the solution to a long-standing mystery in condensed matter physics having to do with high-temperature superconductivity-the ability for some materials to conduct electricity without resistance, even at "high" temperatures approaching -100 degrees Celsius.
Caroline Dutton

Health - 0 views

  • The World Health Organization (WHO) estimates that exposure to smoke from the simple act of cooking is the fifth worst risk factor for disease in developing countries, and causes almost two million premature deaths per year – exceeding deaths attributable to malaria or tuberculosis.
  • Women in developing countries are also at risk of head and spinal injuries, pregnancy complications, and maternal mortality from the strenuous task of carrying heavy loads of firewood or other fuels. Frequent exposure to cookstove smoke can also cause disabling health impacts like cataracts, which affect women more than men, and is the leading cause of blindness in developing countries.
  • Rudimentary wood-fired cookstoves and open fires emit fine particles, carbon monoxide, and other pollutants at levels up to 100 times higher than the recommended limits set by WHO
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  • A randomized-control study in Guatemala led by the University of California, Berkeley, found that halving exposure to indoor air pollution with a chimney stove brought about a reduction in severe pneumonia, and that larger reductions in exposure had more pronounced effects. A systematic review of all available studies on the link between solid fuel use and child pneumonia has found an almost doubling of risk for those exposed.
  • Burns from open fires and unsafe cookstoves are another insidious risk faced by poor households dependent on kerosene, open fires, and unstable metal or clay cookstoves, contributing to a substantial percentage of the estimated 300,000 burn deaths that occur annually
  • While the link between exposure to cookstove smoke and a wide range of health problems such as pneumonia, chronic obstructive pulmonary disease, and lung cancer is well established, the current body of evidence linking cookstoves with other potentially important health effects is compelling but less documented
  • Nearly all of the existing evidence is based on observational studies that compare groups using open fires and traditional cookstoves with those using cleaner fuels, with very little being directly obtained from studies that directly measure the effects of interventions.
  • More evidence is needed to demonstrate that the levels of exposure reduction delivered by clean cookstove and fuels will result in declines in related illnesses and deaths.
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    This is the Global alliance for Clean Cookstoves website. They offer much information about the issues surrounding the topic and their action plan for affecting change!
fergtoo

the Truth About Being a Hero - WSJ - 14 views

  • We all want to be special, to stand out; there's nothing wrong with this. The irony is that every human being is special to start with, because we're unique to start with.
  • n the military I could exercise the power of being automatically respected because of the medals on my chest, not because I had done anything right at the moment to earn that respect.
  • I knew many Marines had done brave deeds that no one saw and for which they got no medals at all.
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  • "A lot of people have done a lot more and gotten a lot less, and a lot of people have done a lot less and gotten a lot more."
  • I got my medals, in part, because I did brave acts, but also, in part, because the kids liked me and they spent time writing better eyewitness accounts than they would have written if they hadn't liked me
  • The only people who will ever know the value of the ribbons on their chests are the people wearing them—and even they can fool themselves, in both directions.
  • he whole assault ground to a halt, except for one kid named Niemi, who had sprinted forward when we came under the intense fire and disappeared up in front of us somewhere.
  • alking to a group of us about when it was a platoon leader earned his pay. I knew, floating above that mess, that now that time had come. If I didn't get up and lead, we'd get wiped.
  • I'm most proud of is that I simply stood up, in the middle of all that flying metal, and started up the hill all by myself.
  • I did it for the right reasons.
  • At this point I saw the missing kid, Niemi, pop his head up. He sprinted across the open top of the hill, all alone.
  • He was a black kid, all tangled up in black-power politics, almost always angry and sullen. A troublemaker. Yet here he was, most of his body naked with only flapping rags left of his jungle utilities, begging for a rifle when he had a perfect excuse to just bury his head in the clay and quit. I gave him mine. I still had a pistol. He grabbed the rifle, stood up to his full height, fully exposing himself to all the fire, and simply blasted an entire magazine at the two soldiers in front of us, killing both of them. He then went charging into the fight, leaving me stunned for a moment. Why? Who was he doing this for? What is this thing in young men? We were beyond ourselves, beyond politics, beyond good and evil. This was transcendence.
  • Crashing out of the clouds into this confusion came a flaming, smoking twin-rotor CH-46 helicopter.
  • I saw Niemi pop into sight again. He sprinted to the downed chopper.
  • the only thing he could think to do was sprint across the open hilltop to see if he could find a place from which he could lay down fire to protect them.
  • Niemi got a Navy Cross.
  • I got a Navy Cross.
  • elicopter pilot
  • ont-page story
  • The kid who borrowed my rifle didn't get anyt
  • hing.
  • It was just about that time I got knocked out and blinded by a hand grenade. I came to, groggy.
  • hen a kid I knew from Second Platoon, mainly because of his bad reputation, threw himself down beside me, half his clothes blown away. He was begging people for a rifle. His had been blown out of his hands.
James Spagnoletti

Göbekli Tepe - Pictures, More From National Geographic Magazine - 67 views

  • The Birth of ReligionWe used to think agriculture gave rise to cities and later to writing, art, and religion. Now the world’s oldest temple suggests the urge to worship sparked civilization.
  • Before them are dozens of massive stone pillars arranged into a set of rings, one mashed up against the next. Known as Göbekli Tepe (pronounced Guh-behk-LEE TEH-peh), the site is vaguely reminiscent of Stonehenge, except that Göbekli Tepe was built much earlier and is made not from roughly hewn blocks but from cleanly carved limestone pillars splashed with bas-reliefs of animals—a cavalcade of gazelles, snakes, foxes, scorpions, and ferocious wild boars. The assemblage was built some 11,600 years ago, seven millennia before the Great Pyramid of Giza. It contains the oldest known temple. Indeed, Göbekli Tepe is the oldest known example of monumental architecture—the first structure human beings put together that was bigger and more complicated than a hut. When these pillars were erected, so far as we know, nothing of comparable scale existed in the world.
  • At the time of Göbekli Tepe's construction much of the human race lived in small nomadic bands that survived by foraging for plants and hunting wild animals. Construction of the site would have required more people coming together in one place than had likely occurred before. Amazingly, the temple's builders were able to cut, shape, and transport 16-ton stones hundreds of feet despite having no wheels or beasts of burden. The pilgrims who came to Göbekli Tepe lived in a world without writing, metal, or pottery; to those approaching the temple from below, its pillars must have loomed overhead like rigid giants, the animals on the stones shivering in the firelight—emissaries from a spiritual world that the human mind may have only begun to envision.
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  • Archaeologists are still excavating Göbekli Tepe and debating its meaning. What they do know is that the site is the most significant in a volley of unexpected findings that have overturned earlier ideas about our species' deep past. Just 20 years ago most researchers believed they knew the time, place, and rough sequence of the Neolithic Revolution—the critical transition that resulted in the birth of agriculture, taking Homo sapiens from scattered groups of hunter-gatherers to farming villages and from there to technologically sophisticated societies with great temples and towers and kings and priests who directed the labor of their subjects and recorded their feats in written form. But in recent years multiple new discoveries, Göbekli Tepe preeminent among them, have begun forcing archaeologists to reconsider. At first the Neolithic Revolution was viewed as a single event—a sudden flash of genius—that occurred in a single location, Mesopotamia, between the Tigris and Euphrates Rivers in what is now southern Iraq, then spread to India, Europe, and beyond. Most archaeologists believed this sudden blossoming of civilization was driven largely by environmental changes: a gradual warming as the Ice Age ended that allowed some people to begin cultivating plants and herding animals in abundance. The new research suggests that the "revolution" was actually carried out by many hands across a huge area and over thousands of years. And it may have been driven not by the environment but by something else entirely.
  • Most of the world's great religious centers, past and present, have been destinations for pilgrimages
  • Göbekli Tepe may be the first of all of them, the beginning of a pattern. What it suggests, at least to the archaeologists working there, is that the human sense of the sacred—and the human love of a good spectacle—may have given rise to civilization itself.
  • n the 1960s archaeologists from the University of Chicago had surveyed the region and concluded that Göbekli Tepe was of little interest. Disturbance was evident at the top of the hill, but they attributed it to the activities of a Byzantine-era military outpo
  • To Schmidt, the T-shaped pillars are stylized human beings, an idea bolstered by the carved arms that angle from the "shoulders" of some pillars, hands reaching toward their loincloth-draped bellies. The stones face the center of the circle—as at "a meeting or dance," Schmidt says—a representation, perhaps, of a religious ritual. As for the prancing, leaping animals on the figures, he noted that they are mostly deadly creatures: stinging scorpions, charging boars, ferocious lions. The figures represented by the pillars may be guarded by them, or appeasing them, or incorporating them as totems.
  • nches below the surface the team struck an elaborately fashioned stone. Then another, and another—a ring of standing pillars.
  • Geomagnetic surveys in 2003 revealed at least 20 rings piled together, higgledy-piggledy, under the earth.
  • he pillars were big—the tallest are 18 feet in height and weigh 16 tons. Swarming over their surfaces was a menagerie of animal bas-reliefs, each in a different style, some roughly rendered, a few as refined and symbolic as Byzantine art.
  • The circles follow a common design. All are made from limestone pillars shaped like giant spikes or capital T's.
  • They hadn't yet mastered engineering." Knoll speculated that the pillars may have been propped up, perhaps by wooden posts.
  • Within minutes of getting there," Schmidt says, he realized that he was looking at a place where scores or even hundreds of people had worked in millennia past.
  • Puzzle piled upon puzzle as the excavation continued. For reasons yet unknown, the rings at Göbekli Tepe seem to have regularly lost their power, or at least their charm. Every few decades people buried the pillars and put up new stones—a second, smaller ring, inside the first.
  • he site may have been built, filled in, and built again for centuries.
  • Bewilderingly, the people at Göbekli Tepe got steadily worse at temple building.
  • Finally the effort seems to have petered out altogether by 8200 B.C. Göbekli Tepe was all fall and no rise.
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