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- Bu səhifədəki naviqasiya:
- Richard Hynes QA
- David Chandler
PAGE 4 March 18, 2009 MIT Tech Talk u
impact(s) of the new stem cell rules for scientists, including those at MIT?
allow many more researchers, includ- ing some at MIT, to conduct research on well-characterized human embry- onic stem (hES) cell lines. The 20 or so lines on which the Bush adminis- tration allowed NIH funding are early lines prepared and maintained in ways that leave much to be desired, both scientifically and ethically, but they were until now the only ones on which most people could work. Since 2001, researchers with access to non-federal funding have developed many new lines using improved techniques and better and more ethical informed consent procedures. There are estimated to be hundreds of such lines. Once the NIH has reviewed which of those lines are deemed acceptable for distribution and for federal funding of research using them, many of them will become avail- able to all scientists to study. MIT scientists are working on methods to develop hES cells for therapeutic purposes, and they will now have more and better lines to analyze. There is a great deal of research needed to work out how to coax hES cells into different cell types and how to use them for research and therapy — that necessary research has been impeded by the Bush administration policy and will now be much enhanced. What the Obama announce- ment does not do is allow federal funding for the devel- opment of any new hES cell lines. That is precluded by current congressional legislation and will require action by the House and Senate to change the law. Such a change seems rather unlikely in the near future. However, development of new lines can continue with non-federal funding and they can presumably be made available for NIH-funded research. Q. How will your own research be affected? A. My own research will not be affected — I do not work on human ES cells. That is one of the reasons I was able to serve on the National Academy of Science commit- tees that established the current Guidelines for Human Embryonic Stem Cell Research. Some of those guidelines (the ones concerning use of existing lines) will presum- ably be incorporated into the NIH regulations. However, the NAS guidelines will still be needed to guide research practices on aspects not eligible for federal funding such as making new lines from IVF embryos or by nuclear transfer.
terms of better understanding and/or treatment of human disease?
ized after a lot of hard work by many scientists. The pace of research has been slowed by the Bush-era restrictions — the new rules will allow more research to be done by more people on more and better hES cell lines. That will undoubtedly speed the development of our understanding and applications of stem cells. Stem cells offer promise both for deeper understanding of disease processes and for the testing of drugs that may ameliorate such diseases, as well as the prospects for actual therapeutic applications of stem cells and of cells and tissues derived from them.
cells to an embryonic state made embryonic stem cell research less important? Or is it important to pursue both areas of research? A. The recent advances on reprogramming of adult cells to a pluripotent state (capable of developing into many cell types) are very exciting and there is hope that they may eventually be an alternative source. However, we do not yet understand reprogramming and it is very inefficient. So we currently need to pursue investigation of multiple approaches — both embryonic and adult stem cells as well as induced pluripotent stem cells. The chances are that each will have some applications and we cannot be sure yet which will prove the most useful in the long run. Richard Hynes Q&A with Richard Hynes ? PHOTO COURTESY NIH.GOV A human embryonic stem (hES) cell colony on a mouse embryonic fibroblast (MEF) feeder layer. Modern manufacturing methods are spectacularly inefficient in their use of energy and materials, according to a detailed MIT analysis of the energy use of 20 major manufacturing processes. Overall, new manufacturing systems are anywhere from 1,000 to one million times bigger consumers of energy, per pound of output, than more traditional industries. In short, pound for pound, making micro- chips uses up orders of magnitude more energy than making manhole covers. At first glance, it may seem strange to make comparisons between such widely disparate processes as metal casting and chip making. But Professor Timo- thy Gutowski of MIT’s Department of Mechanical Engineering, who led the analysis, explains that such a broad comparison of energy efficiency is an essential first step toward optimizing these newer manufacturing methods as they gear up for ever-larger production. “The seemingly extravagant use of materials and energy resources by many newer manufacturing processes is alarming and needs to be addressed alongside claims of improved sustainability from products manufactured by these means,” Gutowksi and his colleagues say in their conclusion to the study, which was recently published in the journal Environmental Science and Technology (ES&T). Gutowksi notes that manufacturers have traditionally been more concerned about factors like price, quality, or cycle time, and not as concerned over how much energy their manufacturing processes use. This latter issue will become more impor- tant, however, as the new industries scale up — especially if energy prices rise again or if a carbon tax is adopted, he says. Solar panels are a good example. Their production, which uses some of the same manufacturing processes as microchips but on a large scale, is escalating dramati- cally. The inherent inefficiency of current solar panel manufacturing methods could drastically reduce the technology’s lifecycle energy balance — that is, the ratio of the energy the panel would produce over its useful lifetime to the energy required to manufacture it. The new study is just “the first step in doing something about it,” Gutowski says — understanding which processes are most inefficient and need further research to develop less energy-intensive alterna- tives. For example, many of the newer processes involve vapor-phase processing (such as sputtering, in which a material is vaporized in a vacuum chamber so that it deposits a coating on an exposed surface in that chamber), which is usually much less efficient than liquid phase (such as deposit- ing a coating from a liquid solution), but liquid processing alternatives might be developed. The study covered everything “from soup to nuts” in terms of standard indus- trial methods, Gutowski says, “from heavy-duty old fashioned industries like a cast-iron foundry, all the way up to semi- conductors and nanomaterials.” It includes injection molding, sputtering, carbon nanofiber production and dry etching, along with more traditional machining, milling, drilling and melting. There were some boundaries on the processes studied, however: The researchers did not analyze production of pharmaceuticals or petro- leum, and they only looked primarily at processes where electricity was the primary energy source. The figures the team derived are actu- ally conservative, Gutowski says, because they did not include some significant energy costs such as the energy required to make the materials themselves or the energy required to maintain the environ- ment of the plant (such as air conditioning and filtration for clean rooms used in semi- conductor processing). “All these things would make [the energy costs] worse,” he says. The bottom line is that “new processes are huge users of materials and energy,” he says. Because some of these processes are so new, “they will be optimized and improved over time,” he says. But as things stand now, over the last several decades as traditional processes such as machining and casting have increasingly given way to newer ones for the production of semicon- ductors, MEMS and nano-materials and devices, for a given quantity of output “we have increased our energy and materi- als consumption by three to six orders of magnitude.” One message from the study is that “claims that these technologies are going to save us in some way need closer scrutiny. There’s a significant energy cost involved here,” he says. And another is that “each of these processes could be improved,” and using the analytical tools developed by the MIT team for this study would be a useful first step in such a detailed analysis. In addition to Gutowski, the study was done by current and former MIT mechanical engineering students Matthew Branham, Jeffrey Dahmus, Alissa Jones and Alexandre Thiriez, and Dusan Sekulic, professor of mechanical engineering at the University of Kentucky. It was funded by the National Science Foundation. MANUFACTURING INEFFICIENCY Study sees ‘alarming’ use of energy, materials in newer manufacturing processes David Chandler News Office Mechanical Engineering Professor Timothy Gutowski led a study showing that modern manufacturing methods are highly inefficient in their use of energy and materials.
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