Previous Editions__________________________________________________________________________SSRL Headlines Vol. 10, No. 11 May, 2010__________________________________________________________________________
Contents of this Issue:
A research team including scientists from SLAC, the University of Manchester,
and the Black Hills Institute of Geological Research used SSRL Beam Line 6-2 to
analyze the chemical composition of a well-preserved Archaeopteryx
fossil. They used the non-destructive technique Synchrotron Rapid Scanning-
X-ray Fluorescence (SRS-XRF) imaging to analyze the presence of trace elements
in the fossilized bone compared to the surrounding rock. They found that the
zinc and copper levels in the fossilized bone are similar to those found in
living bird species. Using a novel form of the SRS-XRF technique, the
researchers were able to visualize phosphorous and sulfur in the feather shaft
impressions in the fossil, showing that, contrary to expectations, some of the
chemistry of the soft-tissue has been preserved.
The researchers point to the power of the SRS-XRF technique to find evidence of
ancient biochemistry. The technique could be used on other fossils that have
not been removed from the surrounding rock. This work was published online by
the Proceedings of the National Academy of Sciences on May 11, 2010.
To learn more about this research see the full scientific highlight
A group of researchers led by Prof. Ian Wilson of The Scripps Research
Institute has found structural similarity between last year's H1N1 strain and
the 1918 influenza virus that also caused a pandemic. They used SSRL Beam Line
9-2 to solve the 3D structure of the HA subunit of the 2009 H1N1 virus to 2.6
Å resolution. They compared their structure of HA of historic H1 flu
strains from 1918 to the present. Their analysis shows a striking similarity
between the surface residues in their HA structure and those of the 1918 virus,
with decreasing similarity of viruses in subsequent years and a significant
drop in similarity around 1940. The researchers also solved a 2.8 Å
crystal structure of the 1918 HA bound to an antibody, which shows that the
region that is conserved between the 2009 and 1918 strains matches the area
recognized by the immune system.
The authors conclude that the resistance of older people to the current H1N1
virus is likely due to antibodies they acquired from flu strains in the early
20th century.
To learn more about this research see the full scientific highlight
A team of researchers led by Profs. Thomas O'Halloran and Alfonso
Mondragón of Northwestern
University and Jim Penner-Hahn of University of Michigan used SSRL Beam Line
9-3 to solve the solution electronic and geometric structure (XAS) and SBC-CAT
and IMCA-CAT at APS to determine the three-dimensional crystal structure of TM
bound to copper and its chaperone protein. They were surprised to find that TM
does not simply sequester copper from Atx1, the copper chaperone, but binds to
a copper-protein trimer complex in a nest-like structure, completely disrupting
the copper transport system. The TM binds to the copper atoms that are bound to
the cysteine sulfurs of chaperone proteins.
Understanding the way TM can shut down the copper ferrying system could lead to
treatments for some cancers, since growing cancers require a supply of copper.
TM may also be useful for treating other diseases, such as familial amyotrophic
lateral sclerosis (ALS), Parkinson's disease, multiple sclerosis, Alzheimer's
disease, and some disorders associated type II diabetes. The research was
published in the January 15 issue of Science.
To learn more about this research see the full scientific highlight
Since its commissioning in 2004 as a third-generation synchrotron facility,
SSRL has been undergoing a process of continuous improvements, with reductions
in emittance, increases in current as well as upgrades of all of its beam lines
with higher performance monochromators, state-of-the-art detectors and new
types of end stations too numerous to mention in a short article. In spite of
all these advancements, the question that never goes away is: where do we go
from here? To answer this question, we in SSRL management have been developing
a strategic plan that looks forward at least five years to guide our thinking.
Read more at:
SPEAR3 was designed to operate at 500 mA with frequent injections with stoppers
open. The goal is to keep the current constant to better than 1% in order to
maintain nearly constant power on the optics to maximize the photon beam
stability. Earlier this year we received final approval to operate all beam
lines in top-off mode (beam line shutters open while injecting), and now we are
nearly ready to start frequent injections to maintain the current to
approximately 1%. We plan to implement the frequent injection phase in the next
few weeks. The number of injections will accordingly increase from 3 per day
(every 8 hours) to 144 per day (every 10 minutes) to maintain 1% current
stability.
After frequent injection has been thoroughly established and once the beam
lines are approved for higher current, the SPEAR3 current will be gradually
increased from 200 mA to 350 mA. Eventually the current will be raised to 500
mA.
Starting this spring and continuing through our regular late-summer shutdown
which begins July 26, an upgrade project funded by the American Recovery and
Reinvestment Act (ARRA) will address two SSRL infrastructure issues related to
Liquid Nitrogen (LN)-cooled crystal monochromators which are key optical
elements in hard x-ray insertion device beam lines at third generation light
sources. The SSRL monochromator design utilizes internally cooled crystals for
optimal thermal performance under power loads approaching a kW when SPEAR3
operates at its full 500-mA design current. This combination of high power
loading and internal cooling poses two challenges: (a) the monochromators
consume a lot of liquid nitrogen (~7000 liters/day for the 11 installed
monochromators with SPEAR3 operating at 500 mA) and (b) the vacuum tight seals
between the monochromator crystals and the LN manifolds are extremely sensitive
to thermal cycling owing to power outages.
The first upgrade will install a new 13,000 gallon LN storage tank and
associated plumbing next to the existing 3,000 gallon LN storage tank on the
hill above Building 120 (B120). This significant increase in LN storage
capacity is essential to ensure a reliable, adequate supply of LN as increased
SPEAR3 current results in greater LN consumption by the monochromators as well
as to provide capacity for future expansion of beam lines and experimental
equipment. The installation of the new foundation for the new tank commenced
early this month, and the new tank will be installed in the middle of July. A
new trench covered with removable steel plates will also be installed from the
new tank to the existing liquid nitrogen distribution system. Part of the B120
parking lot has been blocked off for staging.
The second infrastructure upgrade involves the installation of a pair of 50 KW,
diesel-fueled backup generators strategically placed at two locations near the
SPEAR3 ring and B131. These generators and the associated power distribution
network will be used to provide backup power to the monochromator LN pumps and
heat exchanger units as well as a limited number of other essential systems
such as the house oxygen deficiency monitoring system. Once installed, the
backup power system will eliminate sustained power outages as a source for
LN-cooled monochromator thermal cycling and associated crystal seal failures.
Given the roughly six person weeks required to rebuild a failed crystal seal,
this represents a significant operational enhancement to beam line reliability.
The generator and associated power distribution installation is scheduled to
commence in early August and be completed in mid September.
SSRL user operations will resume after the shutdown with full integration of
these infrastructure enhancements to our facility.
Henry Chapman from the Centre for Free Electron Laser Science at Hamburg/DESY
will talk about the first results on coherent imaging of nano crystals using
LCLS on June 7 at 4:15 pm in the SLAC Panofsky Auditorium. This form of protein
nanocrystallography may open a new avenue for high-throughput membrane protein
crystallography. A new frontier is being opened. Come share in the excitement!
http://www2.slac.stanford.edu/colloquium/details.asp?EventID=293
Make plans to attend our upcoming 2010 LCLS/SSRL Users' Conference and
Workshops, October 17-21, 2010. It's a very exciting time here with new
capabilities at SSRL and LCLS. The ultrafast experiments which are now possible
with the LCLS x-ray laser will push our understanding and technology and will
promote key innovations in such diverse areas as energy science, environmental
science, chemistry, biology and material science.
We welcome your ideas and suggestions for topics and speakers that would be of
interest to the light source user community. The meeting will have plenary
talks, a joint poster session, workshops, and vendor exhibits. This year Thomas
Earnest (tnearnest@lbl.gov), Garth Williams (gjwillms@SLAC.Stanford.EDU) for
LCLS, and Beth Wurzburg (wurzburg@stanford.edu) and Stefan Mannsfeld
(mannsfel@slac.stanford.edu) for SSRL, are co-chairing the conference.
We recently migrated to a new platform for users to submit proposals. From the
joint SSRL and LCLS User Portal, users can update their account and contact
information, submit an End of Run Summary after each experiment, and submit new
proposals. Proposal spokespersons and their authorized lead contacts can also
view their active proposals and beam time allocations as well as submit
requests related to experiments. https://www-ssrl.slac.stanford.edu/URAWI
Stay tuned as additional features are implemented through the portal to
continue to enhance your user facility experience. We welcome your feedback and
suggestions.
REMINDER: New proposals can be submitted three times each year: Submit new
X-ray/VUV proposals by June 1, September 1, December 1; submit new
Macromolecular Crystallography proposals by July 1, December 1, April 1.
LCLS proposals for AMO, SXR, XPP and CXI experiments are due by June 15.
The deadline to register for the SSUN (SLAC-Stanford University-NREL) Energy
Summer School has been extended to June 7—just a week away.
The summer school, set to take place August 9-20 at Stanford University, will
provide an overview of current issues and sustainable technologies in the
energy cycle from generation through collection, storage, distribution and
utilization. This year's sessions will focus specifically on the challenges of
modernizing electric grid infrastructure to develop power systems that are
intelligent, efficient, robust and secure.
For full details and registration, see the SSUN Energy Summer School Web site.
The 1st North American Core Shell Spectroscopy Conference will be held jointly
with the 59th Denver X-ray Conference August 2-6, 2010 at the Denver Marriott
Tech Center Hotel in Denver, CO. http://www.dxcicdd.com/cssc/
Abstract submissions for oral presentations in areas related to core shell
spectroscopy are being accepted until Thursday, June 10
http://www.dxcicdd.com/cssc/cssc_abstract.asp
The conference will feature a special Symposium and Dinner honoring Prof.
Edward A. Stern's contributions to the field of XAFS.
__________________________________________________________________________
SSRL Headlines is published electronically monthly to inform SSRL users,
sponsors and other interested people about happenings at SSRL. SSRL is a
national synchrotron user facility operated by Stanford University for the
U.S. Department of Energy Office of Basic Energy
Sciences. Additional support for
the structural biology program is provided by
the DOE
Office of Biological and Environmental Research, the NIH
National Center for Research Resources and the NIH Institute for General Medical
Sciences. Additional information about
SSRL and its operation and schedules is available from the SSRL WWW
site.
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