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...pine. The hardy evergreen is adapted to life in the hot, parched American Southwest, so it takes more than a little dry spell to affect it. In fact, it requires a once-in-a-century event like the extended drought of the 1950s, which scientists now believe led to widespread tree mortality in the Four Corners area of Utah, Colorado, New Mexico and Arizona...
...researchers were surprised to see up to 10% of the piñon pines die off, even though that dry spell was much milder than the one before. The difference in 2002 was the five decades of global warming that had transpired since the drought in the 1950s. That led terrestrial ecologists at the University of Arizona (UA) to pose the question, With temperatures set to rise sharply over the coming century if climate change goes unchecked, what impact will it have on the piñon pine? (See the top 10 green stories...
...PNAS study, led by Henry Adams, a doctoral student at UA's ecology and evolutionary biology department, also confirms that hotter temperatures actually suffocate trees in dry times. Piñon pines respond to drought by closing the pores in their needle-like leaves to stop water loss. That keeps them from going thirsty, but it also prevents them from breathing in the carbon dioxide they need to live - and eventually, the drought-stressed trees simply suffocate. (See pictures of activists defending backcountry forests from logging...
...research team, led by Dr. Julio Voltarelli of the University of Sao Paulo, is the first to successfully treat type 1 diabetes patients with their own stem cells. The group first reported its initial achievement in 2007, with 15 type 1 diabetes patients who received their own stem cells and no longer needed insulin to control their blood sugar levels. In the new study, a follow-up of their previous work, Voltarelli and his colleagues detailed the same success with an additional eight patients, and also confirmed that in the majority of them, the stem cell transplant led...
...occasional helplessness of the crews - and a new wave of attacks in recent days despite the presence of an international flotilla off Somalia - has led some experts to demand that they be armed in case of attack. On Monday, Gortney told CNN that in addition to beefing up ship defenses on their vessels, shipping companies should deploy armed guards on ships that may come under threat. But such a move has many opponents, who argue that most crews are not properly trained to handle weapons, and such a decision would butt up against the laws of dozens of nations, which...