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SSRL Headlines Vol. 9, No. 8  February, 2009

Contents of this Issue:

Science Highlight — X-rays Focusing on Mercury Water: The Strangest Liquid White Paper on Science and Technology of Future Light Sources Dehmer Announces DOE Accelerator Workshop From the Directors of Photon Science and SIMES: An Energy Facet of the SLAC-Stanford Partnership Uwe Bergmann to Head Chemical and Materials Science and User Support Group Upcoming Workshop on Small-Angle X-ray Scattering and Diffraction Studies in Structural Biology User Experiments Resume on Upgraded BL4-1 and BL4-3 in March Rapid Access Program Expanded to Include BL7-2 XRD Experiments Purdue Scientist on Sabbatical at SLAC to Develop Ideas for Faster Synchrotron Imaging Methods User Research Administration Update

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1.  Science Highlight — X-rays Focusing on Mercury
       (contact: G. George, g.george@usask.ca)

	X-ray fluorescence images of anaesthetized zebrafish larvae.

Organomercury is a well-known poison, and the potential for exposure worries many communities worldwide. Developing embryos are especially susceptible to mercury poisoning, which can result in serious birth defects. Despite the awareness of mercury's adverse health affects, little is known about the mechanisms for mercury toxicity.

A research group led by Graham N. George and Ingrid J. Pickering from the University of Saskatchewan, Canada, used SSRL's beam lines 9-3 and 2-3 to develop a novel approach to identify which cells types attract mercury. They scanned mercury-exposed zebrafish larvae using synchrotron X-ray fluorescence imaging, which gave a direct image of where in the fish the mercury was collecting.

Zebrafish are often used as a model for human development. Cell types that absorb mercury in zebrafish larvae may also collect mercury in human embryos, and knowing which cells absorb mercury is critical to finding the mechanisms of its toxicity. In this study, zebrafish larvae were exposed to varying concentrations of methyl-mercury compounds. The images clearly showed hot-spot areas of high mercury concentrations in the bodies and tissues of the larval zebrafish. The researchers were surprised to discover that mercury strongly collected in the outer layer of the eye lens of the zebrafish larvae, even more than in known target organs such as the brain and liver. This layer is composed of rapidly dividing epithelial cells, since the larvae emerge before their eyes are fully developed. The mechanism for absorption of mercury by these fish eye lens cells may be similar to the mechanism by which rapidly dividing human fetus cells absorb mercury. If mercury similarly concentrates in the eyes of humans, this may help explain how mercury exposure can cause blindness, in addition to damaging the nervous system.

The method that the researchers used also simultaneously locates other elements, including calcium and zinc, in the zebrafish larvae. The technique can also be applied to locating other biologically toxic and important heavy metals such as arsenic and lead, to tracking minerals like zinc, iron and calcium during development, and in understanding the effectiveness of drugs which are supposed to remove toxic metals, such as chelating agents.

To learn more about this research see the full scientific highlight at:
http://www- ssrl.slac.stanford.edu/research/highlights_archive/zebrafish.html

2.  Water: The Strangest Liquid

Over 300 people attended this February 24 Public Lecture presented by Anders Nilsson, Photon Science Professor and Deputy Director of the Stanford Institute for Materials and Energy Sciences (SIMES). Nilsson discussed the many mysteries of water as well as current studies that are revolutionizing the way we see and understand one of the most fundamental substances of life. Water, H2O, is familiar to everyone-it shapes our bodies and our planet. But despite its abundance, water has remained a mystery, exhibiting many strange properties that are still not fully understood. Nilsson raised many questions in his talk such as why does liquid water have an unusually large capacity to store heat? And why is it denser than ice? Nilsson also summarized his investigations into water which are leading to fundamental discoveries about the structure and arrangement of water molecules. Participants in the lecture were buzzing with excitement afterwards, including Nilsson who commented, "It was a lot of work but I loved it. Such an inspiration to speak to such an interesting crowd. It was a kick for me."

Learn more about research activities on x-ray and electron spectroscopies applied to surfaces and interfaces, chemical bonding and reactions on surfaces, hydrogen bonding in water and organic systems, aqueous solutions and interfaces, heterogenous- and biomimetic enzyme catalysis at: http://www-ssrl.slac.stanford.edu/nilssongroup

3.   White Paper on Science and Technology of Future Light Sources
       (contact: J. Stöhr, stohr@slac.stanford.edu)

In this short note, I would like to bring to your attention a joint paper written by scientists from the four DOE labs with synchtrotron radiation facilities: Argonne, Brookhaven, Berkeley and SLAC. The so-called White Paper was sent to DOE in December 2008 and makes the case for the continued investment in x-ray science in the US. In writing the document, the four labs worked together in an unprecedented way to create a compelling vision for the entire field of x-ray science. The paper was timed to be useful in briefing the incoming Obama administration.

The paper leads out with a general introduction of the important role of x-rays in science - past, present and future. In line with the goals of the new administration it then outlines how x-rays may be used to tackle important challenges facing humanity, including developing alternative sources of energy and improving health. It also links x-rays to the Grand Challenges recently formulated by the Basic Energy Sciences Advisory Committee of DOE. It outlines how meeting these challenges will require new x-ray tools that extend our reach into regions of higher spatial, temporal, and energy resolution.

I encourage you to read more about the identified scientific opportunities, the x-ray capabilities needed to address them, and the R&D required to create suitable sources at:
http://www-ssrl.slac.stanford.edu/aboutssrl/documents/future-x-rays-09.pdf

4.   Dehmer Announces DOE Accelerator Workshop
       February 20, 2009 SLAC Today Article by Calla Cofield

The Department of Energy is planning to host an accelerator science workshop in late 2009 to gather input toward "developing a national accelerator research and development stewardship effort," according to Office of Science Deputy Director for Science Programs Patricia Dehmer. Dehmer announced plans for the workshop at the 2009 AAAS meeting in a session on the future of accelerator science in the U.S. In her presentation, Dehmer said that the workshop would focus on "uses of accelerators throughout society, the desired performance characteristics of these and future accelerators, and the R&D efforts in the private and government sectors." The workshop is intended to host scientists as well as representatives from industry. Dehmer said it will be organized by Dennis Kovar, the associate director of High Energy Physics. The DOE has no announced other details about the workshop at this time.

5.   From the Directors of Photon Science and SIMES: An Energy Facet of the SLAC-Stanford Partnership
       February 13, 2009 SLAC Today article by Keith Hodgson and Z.-X. Shen

K. Hodgson		Z.-X. Shen

We are all acutely aware of the importance of energy-the criticality of reliable and sustainable supplies, the role of its cost on our economy, and the impact of energy production and use on the environment. The challenges facing us in the energy arena are not simple and solutions will come only through sustained investment in basic research and development utilizing multidisciplinary strategies that can be translated into practical applications.

Read more at:
http://today.slac.stanford.edu/feature/2009/dir-20090213.asp

6.   Uwe Bergmann to Head Chemical and Materials Science and User Support Group

SSRL is pleased to announce that Uwe Bergmann will take over as manager of Chemical and Materials Science and User Support within the Experimental Systems and Research Division at SSRL. The promotion recognizes Uwe's expertise and leadership in x-ray science. In his new role Uwe will assist the SSRL Directorate in the planning of instrumentation and beam lines to capture new research opportunities and with SSRL's evolution toward PEP-X.

The SSRL organization chart has been updated to reflect this change.
http://www-ssrl.slac.stanford.edu/organization/documents/ssrlorgchart.pdf

7.   Upcoming Workshop on Small-Angle X-ray Scattering and Diffraction Studies in Structural Biology
       (contact: H. Tsuruta, tsuruta@slac.stanford.edu)

A workshop on small-angle x-ray scattering and diffraction studies in Structural Biology will be held April 9-12, 2009 at SSRL. Online Registration is available at:
http://www-conf.slac.stanford.edu/smbsax/

The workshop consists of two days of lectures, and two days of practical sessions on experimental and computational aspects of small-angle x-ray scattering studies in biology, particularly solution x-ray scattering. It will cover the following scientific and technological topics:

• Review of non-crystalline diffraction studies in biology
• Information content of solution scattering
• Complementary use of crystallography and x-ray scattering
• Nucleic acid studies
• Protein folding
• Time-resolved studies
• Structural modeling approaches using solution scattering data
• Lipid membrane diffraction studies for membrane protein crystallization
• Diffraction studies on fiber and other non-crystalline biological systems
• Experimental facilities for structural biology on SSRL BL4-2
• Software developments at BL4-2
• ATSAS software tutorials
• Experimental tutorials on BL4-2