A new government report predicts that in the next 50 years there will be significant shifts in precipitation across the United States as a result of increased carbon dioxide in the atmosphere. The report predicts that the arid Southwest and West, already struggling with chronic water shortages, will become even drier. In contrast, parts of the Northeast and East will experience up to 20% more precipitation, leading to increased runoff in streams and rivers. These changes are likely to disrupt water supplies, affect agricultural and forest productivity, and alter ecosystems.
So it’s not just a rising average temperature that we have to worry about with global warming; shifting weather patterns are likely to be just as disruptive. See “Synthesis and Assessment Product 4.3 (SAP 4.3): The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States”, at climatescience.gov.
Selasa, 27 Mei 2008
Kamis, 22 Mei 2008
Pet Cloning Goes Commercial
A California biotech company called BioArts plans to hold a public auction to clone five dogs. The scientist involved in the actual cloning will be the South Korean researcher who cloned Snuppy, the male Afghan hound pictured in Human Biology, 5th ed. (p. 418), and who later claimed (fraudulently) to have cloned human embryos.
The auction will be held July 5th through 9th online, with bidding to start at $100,000. The company promises the buyer a puppy that resembles the original dog, guaranteed healthy for a year. The company says that the success rate with cloning dogs has improved to the point that 25% of all embryo transfers now result in a puppy, and that the puppy survival rate is 80%.
Human cloning can’t be far behind. The sticking point is the success rate and the health of the clone – do we really think that a survival rate on the order of 80% would be worth the risk? No one knows the long-term health risks.
The auction will be held July 5th through 9th online, with bidding to start at $100,000. The company promises the buyer a puppy that resembles the original dog, guaranteed healthy for a year. The company says that the success rate with cloning dogs has improved to the point that 25% of all embryo transfers now result in a puppy, and that the puppy survival rate is 80%.
Human cloning can’t be far behind. The sticking point is the success rate and the health of the clone – do we really think that a survival rate on the order of 80% would be worth the risk? No one knows the long-term health risks.
Senin, 19 Mei 2008
From Sewage to Drinking Water
Los Angeles officials are proposing to recycle heavily treated sewage water back into the ground. The water would eventually make its way into the aquifers that supply drinking water to the city (“Los Angeles Eyes Sewage as a Source of Water”, LA Times May 15, 2008). The plan is understandably controversial, with some residents complaining that it should be put to a vote rather than decided upon by city officials.
A similar plan was abandoned in the 1990s after a public campaign was mounted against it. But this time around the critics seem to be less vocal, in part because the chronic water shortage in LA is predicted to only get worse and in part because the technology for cleaning up sewage water keeps getting better and better.
It might be interesting to ask your students if they would vote for such a plan in their community, or ask them what THEY would see as the best way to solve a water shortage problem. You could also ask them to look into and report on current techniques for treating sewage water.
A similar plan was abandoned in the 1990s after a public campaign was mounted against it. But this time around the critics seem to be less vocal, in part because the chronic water shortage in LA is predicted to only get worse and in part because the technology for cleaning up sewage water keeps getting better and better.
It might be interesting to ask your students if they would vote for such a plan in their community, or ask them what THEY would see as the best way to solve a water shortage problem. You could also ask them to look into and report on current techniques for treating sewage water.
Sabtu, 10 Mei 2008
Fat Cells are Replaced Throughout Life
It is known that every adult has a relatively constant number of fat cells - obese people just tend to have more of them than thin people. When we gain or lose weight our fat cells swell or shrink, but the number of fat cells stays the same. This is one reason why it is so hard for some obese people to lose weight; they are constantly fighting internal homeostatic mechanisms that work to maintain their fat cell's "normal" weight.
But now, researchers have discovered that although you do have a constant number of fat cells throughout life, they are not the same cells. About 10% of them die each year and are replaced by new ones.
No one knows for sure what determines how many fat cells each person has. But the findings open up interesting new avenues for weight control research. If we could determine what regulates the number of fat cells and then alter that regulation, or if we could slow the rate of fat cell division, we might have a new way to fight obesity.
But now, researchers have discovered that although you do have a constant number of fat cells throughout life, they are not the same cells. About 10% of them die each year and are replaced by new ones.
No one knows for sure what determines how many fat cells each person has. But the findings open up interesting new avenues for weight control research. If we could determine what regulates the number of fat cells and then alter that regulation, or if we could slow the rate of fat cell division, we might have a new way to fight obesity.
Senin, 05 Mei 2008
Texas Blocks 'Creation Science' Master's Degree
The Texas Higher Education Coordinating Board voted unanimously last month not allow the Institute for Creation Research (ICR) to grant online Master of Science degrees in science education. The ICR makes no secret of the fact that it supports a literal interpretation of the Bible, including the creation of Earth in six days.
“Religious belief is not science,” said the state’s commissioner of Higher education in recommending to the board that they disallow the ICR application. He added, “Science and religious belief are surely reconcilable, but they are not the same thing.”
“Religious belief is not science,” said the state’s commissioner of Higher education in recommending to the board that they disallow the ICR application. He added, “Science and religious belief are surely reconcilable, but they are not the same thing.”
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