Thursday, August 28, 2008

E-Stuff - New feature on ISEL Update - Science Progress

As an experiment, we are going to blog on a database or an electronic journal of interest, one per month during the semester. If you have any suggestions, please feel free to use the comment or email us.

This idea occurred to me when I stumbled upon a journal I hadn't known about before,
Science Progress, which is our inaugural subject for this series.

What I like best about Science Progress is that it provides review articles on hot topics aimed at college students or scientists who are not experts in the field in question. Librarians often get students looking for articles which are written in language they can understand.

Most issues don't have a theme, and cover the waterfront, so to speak. But some issues have theme topics. For instance, in the current issue (Vol. 92, no. 2 - July 2008), all but one of the articles are about the effects of climate change on polar regions; it includes individual articles on climate change and whales and seals, polar bears, arctic fox, microbiology of the Antarctic Peninsular region, and (the non-polar one) butterflies as indicators of climate change. The articles are not short - the shortest in this issue is 9 pages (the one on butterflies), the longest 34 (whales & seals), and all contain extensive bibliographies, as one would expect in a review article.

The UMass Amherst campus has access to current issues electronically only, through a vendor, IngentaConnect. Publication of Science Progress seems to be a little erratic - but generally they put out 3-4 issues per year. It is published in Britain, so there is a tendency for the articles to be focused on Britain - e.g., the article above is about butterflies in Britain.

If you'd like to see recent issues of this journal (back to 2001), use the Library's link to the title through the
catalog or e-journal list, or click here on this IngentaConnect link to Science Progress. We have earlier issues (v.11 (1916)-v.87 (2004)) in paper as well.

Solar dish scales down - project of MIT students

Sustainable Futures - from environmentalresearchweb - Aug 14, 2008

Solar dish scales down

A group of students at the Massachusetts Institute of Technology (MIT), US, has developed a small, easy to make, cost-efficient solar dish that might be mass produced by the company they have set up, RawSolar.

The dish consists of a 12-foot wide, mirrored parabola that concentrates sunlight by a factor of 1000. Attached to the dish's centre is a coil of copper tubing 12 foot long that has water running through it. When the dish is pointing directly towards the sun, the water in the coil instantaneously heats up to form steam. This is because the sun's rays converge onto the copper coil, providing intense energy. The steam comes out of the far end of the tube under the dish.

Led by Spencer Ahrens, the students hope that RawSolar will one day mass produce the dishes. They could be set up in large arrays to provide steam for heating, industrial processes, generating electricity, or even air conditioning.

The beauty of the new dish lies in its size – it is smaller than conventional dishes and so requires less support structure, which means it costs less, too. It is also robust (it has already survived a thunderstorm), uses easily-available, off-the-shelf parts and was made by hand, explains team member Matt Ritter.

The structure was based on a design by Doug Wood, an inventor based in Washington state. Wood patented key parts of his design – the rights to which he has now signed over to the MIT students – and says that Ahrens' team has made significant improvements to the original patterns. "They really have simplified this and made it user-friendly so that anyone can build it," he explained.

The students made their solar dish by riveting aluminium tubing to a steel crossbracing. Strips of mirror were then fixed to this frame and the coil collector at the top of the tube painted black.
The MIT team says the system could produce heat from steam for lower costs than that from oil or natural gas.

"I've looked for years at a variety of solar approaches, and this is the cheapest I've seen," said MIT Sloan School of Management lecturer David Pelly, in whose class this project first took shape last autumn. "And the key thing in scaling it globally is that all of the materials are inexpensive and accessible anywhere in the world." Pelly adds that the technology could scale without subsidies – a first in the solar dish world.

Tuesday, August 26, 2008

Epigenetics on Nova scienceNOW

I've been trying to catch Nova scienceNOW (yes, that's how it's written) on PBS with that engaging host, astronomer and American Museum of Natural History researcher, Neil deGrasse Tyson. It's one more way to keep up with new developments in a range of sciences, and to see what merits the attention of the mainstream. Last week, there was a piece on epigenetics, (a repeat show, I think) which I had never heard of (so shoot me), or at least it had never registered with me. Fascinating stuff illustrated with why identical twins can develop such disparate lives - one getting a life-threatening disease when the other doesn't - we're finally unravelling how gene expression works.

There are some resources about epigenetics on the site linked above, including a video of the segment from the show.

Wednesday, August 06, 2008

SciFinder now available on the Web.

Chemical Abstracts Service (CAS) now offers SciFinder on the web after many years of providing access via the locally installed client platform. To connect to SciFinder on the web the user must fill out a one-time registration form setting up an individual account with a username and password. Note that the user will need to be on a computer with a UMass IP address; off campus users will need to go through the library’s SciFinder page so that they can be authenticated.

The UMass Amherst Library has purchased access to SciFinder for 6 simultaneous users; only a limited number of simultaneous users can use either the web or client version, so please remember to logout when done.

For more information visit the library page about SciFinder.

For a comparison chart between SciFinder Scholar and the web version of SciFinder visit the Swain Libraray News blog at Stanford University.

New Piece of Climate Change Puzzle Found In Ancient Sedimentary Rocks by UMass Amherst Researchers


Press release from the UMass Amherst Office of News & Information.

July 23, 2008
Contact:
Steven Petsch 413/545-4413

AMHERST, Mass. – University of Massachusetts Amherst researchers have added a new source of carbon dioxide to the complex climate change puzzle by showing that ancient rocks can release substantial amounts of organic matter into Earth’s rivers and oceans, and that this organic matter is easily converted by bacteria to carbon dioxide, which enters the atmosphere and contributes to climate change.

“Sedimentary rocks contain the largest mass of organic carbon on Earth, but these reservoirs are not well-integrated into modern carbon budgets” says Steven Petsch, a professor of geosciences. “Since we need to know the budget of the natural carbon cycle in order to determine human climate impacts, this information will lead to more accurate climate modeling.” The research was conducted by Petsch and UMass Amherst graduate student Sarah Schillawski.

In a study published in the July issue of Global Biogeochemical Cycles, Petsch and Schillawski focused on black shales from Kentucky. Black shales are rich in a type of organic matter called kerogen that contains carbon. Kerogen can turn into oil and natural gas when the rocks are heated. The first step was to determine how much organic carbon could be released from the rocks by simulating the weathering process in the laboratory.

Samples of the shale were placed in glass columns, and the effects of weathering were duplicated by running water through the samples for one year. Kerogen is thought to be difficult to dissolve, but the results of the column studies showed a slow, sustained release of organic matter from the rock. Over the course of one year, the rock samples had lost approximately 0.3 percent of their total organic carbon.

The next step was to determine whether this hard-to-digest organic matter could be broken down by bacteria into carbon dioxide. Using common bacteria found in natural waters, including the Quabbin Reservoir, Petsch found that essentially all of the dissolved organic matter in water from the column studies was rapidly degraded by bacteria over a period of nine days.

“This was the most surprising finding in the study, since these bacteria are adapted to digest organic matter from things like leaves and acorns, which is similar to carbohydrates consumed by humans,” says Petsch. “The presence of microorganisms capable of using kerogen may have significant implications for the global-scale cycling of carbon and oxygen.”

Petsch has also studied the release of carbon from sedimentary rocks by soil bacteria, which is another way that ancient carbon can be converted into carbon dioxide. “We have found outcrops of the New Albany Shale, which is usually black, that have turned a light brown color as bacteria consume carbon where the overlying soil meets the weathered rock,” says Petsch.

According to Petsch, the bottom line is that the release of organic material from sedimentary rocks contributes approximately 2 percent of the carbon dioxide that enters the atmosphere each year. While this may seem like a small amount, it is another piece of the puzzle that can be used when determining how to reduce greenhouse gas emissions in the coming decades.