Workshop held
in honor of
Daniel Chemla's 65th birthday
 A
Molecular Nanoscience Workshop was held at Berkeley Lab on
November 21st to honor retiring ALS Director Daniel Chemla
on the occasion of his 65th birthday. In welcoming the attendees,
Lab Director Steve Chu remarked that, even at Bell Labs (where
their paths first crossed), Daniel always seemed to have a
really good sense of where things were going. Underlining
this point, Associate Director Paul Alivisatos shortly thereafter
directed attention to stage left, where the auditorium's window
shades were retracted to reveal a panoramic view of the Molecular
Foundry building, now nearly complete on the adjacent hillside.
Daniel was then presented with a plaque bearing his name and
likeness, which will grace the Foundry's "Chemla Seminar
Room."
Joseph Zyss of Ecole Normale Supérieure
(ENS) in Cachan, France, a close friend and colleague since
1975, presented Daniel with an honorary doctorate and medal
from that institution on behalf of all his French colleagues
in honor of his many accomplishments. Slides from a talk and
reception held in Cachan the previous week showed many of
said colleagues, as well as Daniel's sister, Annie, who attended
for Daniel. Former Lab Director Chuck Shank then took the
podium to announce the publication of a special issue of the
journal Chemical Physics on the topic of "Molecular
Nanoscience—In honour of Daniel S. Chemla on his 65th
birthday" (Chem. Phys. 318,
Issues 1-2, 15 November 2005). The issue is divided into three
sections reflecting the major areas Daniel helped pioneer
and where his contributions stand out as landmarks to this
day: (1) Single-molecule and nanoscale photonics in organics
and biosystems, (2) Semiconductor-based nanoparticles and
nanoprobes, and (3) Physics of quantum-confined excitations,
localization, and wave-packet dynamics.
Berit and Daniel Chemla at last week's
workshop.
Daniel, accompanied by his wife, Berit,
and son Yann, who spoke for him, thanked his students, colleagues,
and the organizing committee. And, admitting that he is not
much for pomp and ceremony, proposed to let the scientific
talks begin. The speaker list included representatives recalling
all phases of Daniel's remarkable career, from his early work
in France, to his highly productive years at Bell Labs, to
his tour de force leading two major divisions at Berkeley
Lab. The spectrum of science ranged from laser-slicing of
synchrotron radiation to microtesla magnetic resonance imaging
to photosynthetic complexes as nature's nanodevices. A common
thread throughout was Daniel's personal and institutional
impact as a scientist, teacher, and administrator. The workshop
closed with a reception and dinner at the Berkeley Faculty
Club, where master of ceremonies Wayne Knox (Director, Institute
of Optics, University of Rochester) gave a retrospective of
Daniel's career, capped off by cake and a rousing rendition
of "Happy Birthday."
Joseph Zyss looks on as Daniel cuts
the cake.
While attendance at the workshop and
dinner was necessarily limited for logistical reasons, everyone
is invited to visit the workshop
Web site documenting the event. The site's "Daniel
Chemla Gallery" will be updated in the coming weeks with
photos, presentations, and video from the workshop. The organizers
also welcome any additional contributions, including photos,
science highlights, and messages for Daniel, from friends,
colleagues, students, co-workers, and well-wishers in general,
for posting on the site. Simply send an email to chemlabirthday@lbl.gov
to participate in the celebration of the distinguished career
of our friend and colleague, Daniel Chemla.
Biological imaging
by soft x-ray
diffraction microscopy
Electron and x-ray microscopes are a
valuable tool for both the life and materials sciences, but
they are limited in their ability to image with nanometer-scale
resolution in three dimensions nonperiodic objects that are
several microns in size. To fill this gap, the technique of
coherent x-ray diffraction imaging now under development takes
advantage of the penetrating power of x rays while simultaneously
removing the limitations imposed by lens-based optical systems.
Researchers from Stony Brook University, in collaboration
with scientists at the ALS and Cornell University, have taken
a large step in this direction by using a lensless x-ray diffraction
microscope to image a freeze-dried yeast cell to better than
30-nm resolution. Images were made at several angular orientations
of the cell. Full
story.
Publication about this research: D. Shapiro,
P. Thibault, T. Beetz, V. Elser, M. Howells, C. Jacobsen,
J. Kirz, E. Lima, H. Miao, A.M. Neiman, and D. Sayre, "Biological
imaging by soft x-ray diffraction microscopy," Proc.
Nat. Acad. Sci. USA 102, 15343 (2005).
Contact: David A. Shapiro, DAShapiro@lbl.gov
Structural basis
for activation
of cholera toxin
Cholera is a serious disease that claims
thousands of victims each year in third-world, war-torn, and
disaster-stricken nations. The culprit is the bacterium Vibrio
cholerae, which can be ingested through contaminated
food or water and colonizes the mucous membrane of the human
small intestine. There, it secretes cholera toxin (CT), a
protein whose A1 subunit (CTA1) triggers a series of events
that culminates in the massive efflux of electrolytes and
water into the intestinal cavity, causing the watery diarrhea
characteristic of cholera that, if left untreated, can lead
to severe dehydration and death. Crystal structures of the
CTA1 subunit in complex with its activator molecule (ARF6)
reveal that binding of the ARF6 "switch" elicits
dramatic changes in CTA1 loop regions, exposing the toxin's
active site. The extensive CTA1-ARF6 interface mimics recognition
of ARF6's normal cellular protein partners, which suggests
that the toxin has evolved to exploit the molecular switch's
promiscuous binding properties. Full
story.
Publication about this research: C.J.
O'Neal, M.G. Jobling, R.K. Holmes, and W.G.J. Hol, "Structural
basis for the activation of cholera toxin by human ARF6-GTP,"
Science 309, 1093 (2005).
Contact: Wim G.J. Hol, wghol@u.washington.edu
Helmholtz-Humboldt
Award
for Charles Fadley
 ALS
Professor Charles S. Fadley has won one of this year's Helmholtz-Humboldt
Awards from the Alexander von Humboldt Foundation. Each year,
the German-based Helmholtz Association of fifteen government
research laboratories and the Alexander von Humboldt Foundation
jointly grant up to six research awards to internationally
acknowledged scientists from abroad in recognition of their
achievements in research to date. The awards come with cash
and an invitation to undertake research in Germany with government
laboratory and university partners. Fadley is a leading authority
on photoelectron spectroscopy. While in Germany, he will collaborate
with various scientific groups on standing-wave studies of
nanostructures and spin-polarized and dichroic holography.
For more information about the award, go to the Humboldt
Foundation Web site.
Fadley is currently a Distinguished Professor
of Physics at the University of California (UC), Davis, and
a Senior Faculty Scientist in Berkeley Lab's Materials Sciences
Division, holding one of three joint UC–Berkeley Lab
ALS Professorship appointments. The Helmholtz-Humboldt Award
comes on the heels of an American Vacuum Society M.W. Welch
Award that Fadley received earlier this year "for the
development of novel techniques based on photoelectron spectroscopy
and synchrotron radiation, and their application to the study
of the atomic, electronic, and magnetic structure of surfaces
and buried interfaces." Congratulations once again to
Chuck on receiving this prestigious award!
Call for general
sciences proposals:
Due January 4, 2006
The User Services Office is accepting
general-user proposals from scientists who wish to conduct
research in the general sciences at the ALS during the running
period from July through December 2006. The deadline for submissions
is Wednesday, January 4, 2006. (This deadline does not apply
to protein crystallography proposals, which have a separate
process and schedule.) To submit a new proposal, go to the
online ALS
General User Proposal and Request for Beamtime form.
 If
you have an existing proposal for which you would like to
receive beam time during the July through December 2006 cycle,
you must submit a Proposal Renewal Form. Scientists with existing
proposals that are eligible for renewal have been sent instructions
on how to request a login and password to access their proposal
information and forms. Proposals can be renewed for up to
three six-month cycles following their initial submission.
After three cycles, a new proposal must be submitted.
The numeric rating for each proposal
will be communicated to the user along with any comments that
might have been added by the Proposal Study Panel. The cutoff
rating for each beamline in the previous proposal cycle is
published on the Web (see item below). The following resources
are available for further information:
ALS
User Services Administrator
General-user
proposal process
ALS online forms
Beamline
information
Contact: alsproposals@lbl.gov
Latest scores
for general-user
proposals posted
User proposals for the general sciences
submitted on July 5, 2005, have been reviewed by the Proposal
Study Panel and scored on a scale of one (highest) to
five. Beam time for the running period from January through
June 2006 has been allocated based on each proposal's ranking
in relation to all other proposals for a given beamline. In
cases where proposal requests for a specific beamline exceeded
available beam time, a cutoff score was assigned after which
no beam time was allocated. The number of proposals for the
cycle was 302, down from 310 in the previous period. The number
of eight-hour shift requests for the upcoming cycle was 5236.
A total of 2935 shifts, equal to about 56% of the total time
requested in the proposals, was allocated. For more detailed
results, including beam-time score distributions and cut-off
scores, go to the proposal
scores Web page. The schedule
for the upcoming running period has also been posted.
Contact: Gary Krebs, GFKrebs@lbl.gov
ALS Users' Executive
Committee Election:
Meet the candidates
The ALS Users' Executive Committee (UEC)
invites users and staff to take a look at the nine candidates
running in this year's UEC election. A short biography and
photograph of each nominee can be viewed at UEC
Candidate Biographies. Three candidates will be elected
to replace retiring UEC members Dan Dessau (University of
Colorado), Keith Jackson (Center for X-Ray Optics), and Gary
Mitchell (Dow Chemical Company). Online voting will begin
shortly; users and staff will be notified by email when voting
begins. All users and staff wishing to participate in the
election must have a valid email address on file with the
ALS User Services Office in order to vote.
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