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Wolfgang Eberhardt on Light Sources: Getting the Balance Right Print


Wolfgang Eberhardt at the Advanced Light Source, September 2015. Click the image to watch the video of his talk, "Diffraction Limited Storage Rings and Free Electron Lasers—Why Do We Need Both?"

As a graduate student in the 1970s, Wolfgang Eberhardt conducted his first experiment at the old DESY synchrotron in Hamburg, Germany. A so-called "parasitic" operation on a high-energy physics ring, it had tremendous difficulties, including highly erratic, fluctuating pulses.

"Nowadays," he says, "nobody would even consider doing experiments under those conditions." Nevertheless, photon science at the time was new, so "whatever you looked at, whatever you studied, it was pretty much for sure that nobody had seen that before. It was very exciting."

Eberhardt, a Professor of Physics at the Technical University of Berlin and a Leading Scientist at Helmholtz Zentrum Berlin (HZB) and the Center for Free-Electron Laser Science (CFEL) at DESY, is currently wrapping up an extended visit to the ALS, working on furthering our basic understanding of organic solar-cell materials.

In addition to serving as Scientific Director of BESSY (the synchrotron in Berlin) from 2001–2008, Eberhardt has published over 300 refereed papers on topics ranging from the development of angle-resolved photoemission, to femtosecond magnetization dynamics, to scattering and holography with coherent synchrotron radiation. He is an internationally respected and sought-after expert in the generation and application of synchrotron radiation and has served on a long list of advisory boards, councils, and committtees across Europe, the US, and Asia. In 2008, he co-chaired with Franz Himpsel a DOE BESAC workshop on "Next-Generation Photon Sources for Grand Challenges in Science and Energy."

Now, with a diffraction-limited ALS upgrade (ALS-U) on the horizon, Eberhardt agreed to give a special ALS seminar this month on "Diffraction Limited Storage Rings and Free Electron Lasers—Why Do We Need Both?" He pointed out that synchrotron science at storage rings has been fantastically successful, but attention has recently turned somewhat to the construction of free-electron laser facilities. "There's lots of science, very exciting science out there," Eberhardt said in an interview following the seminar, "and the science cannot be mapped uniquely onto one specific facility." While this message came through in the 2008 BESAC workshop report, he said, "the distinction—what can you do better with what facility—that is still a learning process."

Eberhardt summarized his current understanding of that distinction: "If you want to look at processes, if you want to look at function of materials, you need to do movies, consecutive interrogations of the same object and see how it evolves under certain conditions. How a reaction progresses, for example. So you can't take one snapshot and know it all—what happens. This is clearly the realm of the new diffraction-limited storage rings."

On the other hand, "if you want to have snapshots at the best determined time to investigate and freeze a state of a system, then that's the free-electron laser, because that allows you to get really the best time resolution. But it only allows you to get a single picture—or maybe a double picture—it doesn't allow you to really do a full movie," before the sample is destroyed or changed by the x-ray pulses.

Ultimately, achieving the right balance between ring sources and linac sources is a many-dimensional problem that can't be captured in a simple two-dimensional matrix of science areas vs. photon attributes. You also have to take into account timing, budgets, risks, and changes in technology over time.

"When the ALS was built," says Eberhardt, "it was the most modern, most fantastic machine that existed in the world. All the scientists came from everywhere to do experiments. It was really fantastic." Now, more modern, diffraction-limited x-ray facilities are being built, such as MAX IV in Sweden. While there are always certain risks involved whenever you try something totally new, with respect to the MAX IV design, "right now it looks like these risks can be handled and the challenges can be met."

Eberhardt is quick to note that the ALS has not stood still, but has been continuously upgraded. "The machine has improved as much as it can be in the normal program, the instrumentation is continually being upgraded," he says. "But right now, it's due for a major upgrade, this refurbishment, simply because accelerator design has advanced. And that's what the ALS-U is about."

Eberhardt cautions against simple calculations about cost per experiment. "What is the Higgs boson worth?" he asks. "Certainly in physics, chemistry, there are many different Higgs bosons around." When pressed on the question, Eberhardt cited the example of high-temperature superconductivity. "It's a very strange mechanism; to really pin that down and say why are all these materials behaving that way, that would be very exciting." On the question of whether we really need both diffraction-limited storage rings and free-electron laser facilities or can we manage with just one or the other, Eberhardt is clear: "My firm position on that one is you really need both, because they are really complementary."

Footprinting Technique Gives ALS Users New Insights Print


Recent research at ALS Beamline 5.3.1, detailed in this month’s Science Highlight, revealed that an important photosynthetic mechanism called “nonphotochemical quenching” is triggered by the translocation of the carotenoid pigment within a critical light-sensitive protein called the Orange Carotenoid Protein (OCP). The x-ray footprinting (XFP) technique developed at 5.3.1 allowed researchers to confirm that this translocation actually occurs when OCP is in its natural solution environment and was not due to structural changes that the protein undergoes during crystal formation.

The ALS XFP experts at Beamline 5.3.1. From left: Research Scientist  Sayan Gupta, Beamline 5.3.1 Scientist Rich Celestre, and BCSB Head  Corie Ralston.

XFP, a powerful technique for the study of macromolecular structures and dynamics of proteins and nucleic acids in solution, is relatively new to the ALS, though it was first developed more than 10 years ago by scientist Mark Chance at the NSLS. Two years ago, Head of the Berkeley Center for Structural Biology (BCSB) Corie Ralston obtained LDRD funding to bring the technique to the ALS, partly based on the fact that the only other XFP capability available in the U.S. was at the NSLS, and soon to be unavailable due to NSLS closure. The ALS is currently supporting NSLS users while they recommission their own XFP beamline.

“The user base is also big enough that we need more than one beamline with XFP capability,” says Ralston. “Even once NSLS is back up in 2016, we plan to continue to offer the technique.”

Ralston describes XFP as being “highly complementary to crystallography,” though one of its main advantages happens to be that it doesn’t require a crystal.  Using XFP, researchers can look at proteins in solution and see where the protein is solvent-accessible. “So if you want to look at a protein-protein interaction, for example, where the proteins meet they exclude solvent and you get a protected patch that can be detected,” says Ralston.

During XFP, the x-rays traveling through a solution generate hydroxyl radicals, which then modify the amino acids in the protein that are solvent accessible. They don’t modify the ones that aren’t solvent accessible, which then basically creates a map of all the solvent-accessible areas on a protein. “You can look at huge complexes; the size of the protein doesn’t matter,” says Ralston. “Whereas, in crystallography, trying to crystallize large complexes is very challenging.”

Another benefit of XFP is that it can be done at close to physiological conditions, which gives researchers a more real-life representation of the protein. “XFP is really useful for looking at a protein changing in solution as a function of pH or salt concentration, for instance, or to watch protein-protein interactions and see where they are binding,” says Ralston. “Having this other technique that can give us more information is just really helpful.”

XFP has been a team effort at the ALS, with research scientist Dr. Sayan Gupta, previously employed at NSLS, working out the kinks of the ALS XFP system on the beamline floor. Beamline 5.3.1 scientist Rich Celestre has also been heavily involved, especially with working out a way to focus the high brightness beam at 5.3.1, allowing researchers to utilize microsecond exposures, which opens up the possibility for time-resolved studies on proteins. XFP has also been deployed at Beamline 3.2.1, which offers high flux but not high brightness.

User Experiment Safety Process Update: For Experiments After August 17 Print


by Sue Bailey, User Services Group Leader

The ALS is updating the User Experiment Safety Process. The main change that will affect users is a new requirement to complete an Experiment Safety Sheet (ESS) for each visit and for each beamline. This is a change from current procedure where an ESS can be valid for up to one year and may cover more than one beamline.

We want this to work well and to help you, so if you have feedback on these changes, I encourage you to  This e-mail address is being protected from spambots. You need JavaScript enabled to view it . Your primary point of contact during the change, for submitting and handling ESSs, will be the ALS Experiment Coordinator, This e-mail address is being protected from spambots. You need JavaScript enabled to view it , with other members of the safety team and user services as back up.


Summary of Changes

  • In general, we will require your ESS submission a minimum of 1–2 weeks before the experiment (earlier is also good). But see below for more hazardous experiments.
  • An ESS will be required for each visit and will include the experiment date.
  • The ESS will only cover work at a single beamline; a group working on two beamlines at the same time will require two separate ESSs.
  • The ESS should only cover the work of a single group.
  • To simplify submitting each ESS, we are making it easy to use a previous ESS as a template.
  • Automated emails will be sent to remind users to submit an ESS, starting 3 weeks before the expected start of the experiment. Since schedules sometimes change, we may miss occasional reminders—this does not prevent you submitting an ESS—you know when your experiment will happen.

Very early submission of an ESS is needed for experiments requiring additional review.

Some experiments require additional safety documents and review by subject matter experts. These include:

  • All biological materials
  • Radioactive materials
  • Hazardous chemicals
  • Lasers
  • Electrical equipment the user is bringing (anything with a plug)

For such experiments, please submit your ESS in good time to allow our staff to help you get ready. If the final details of every sample and experimenter will not be known until later, just give us what you have. An initial submission several weeks before the experiments alerts us to start a dialogue on handling the samples and equipment.

ALS Postdoc Recognized for Outstanding Thesis Print


Søren Ulstrup, an ALS postdoc who received his Ph.D. from Aarhus University in Denmark last year, was selected by the Aarhus University Research Foundation as one of five promising young scientists to receive its prize for outstanding doctoral thesis. The title of Søren's thesis was "A Direct Study of the Electronic Structure of Graphene."

With these awards, the Aarhus University Research Foundation recognizes work that includes a significant amount of new and important results that have been communicated extensively to both peers in the scientific field and to a broader audience via public media. The official Aarhus University Research Foundation video of Søren describing his work is posted below with English subtitles:


Søren's full award citation (in Danish) can be found at the Aarhus University Research Foundation site. In translation, it says, in part:

Laser Pulses Reveal Huge Potential in 2D Fabric

With his studies of graphene, Søren Ulstrup, among others, showed how to manipulate the substance's electronic properties and its quality in the manufacturing process. And these factors are also crucial.

"Graphene has some really wonderful features that you want to use in combination with other materials. It can be used for enhancing surfaces and protection against corrosion, but because of its ability to conduct electricity and heat, it is particularly relevant to electronic components and energy storage in solar cells, for example," he says.

"We exposed the graphene to some ultrafast laser pulses. And it turned out that with the laser light we could bring many of the material's electrons out of their ground state. The energy the free electrons create inside the graphene could be 'harvested' in a solar cell," says Søren.

The consequence is that a graphene-based solar cell has the potential to be extremely effective. Whether it works in practice remains to be seen. But the international attention on Søren Ulstrup's result is beyond doubt—and he leaves it to others to build the solar cell.

Søren is currently investigating the electronic properties of new low-dimensional material systems with the MAESTRO group at Beamline 7.0.2. The goal is to use state-of-the-art photoemission experiments with nanoscale spatial resolution in addition to energy and momentum resolution to uncover the electronic texture of complex nano- and micron-sized materials.

His postdoc project at the ALS is funded by the Sapere Aude program of the Danish Council for Independent Research and has a duration of 2 years and 3 months.



Moore Foundation Funds ALS Researchers for Promising New Technique for Studying Materials Print

A novel x-ray scattering concept by researchers at Lawrence Berkeley National Laboratory’s (Berkeley Lab) Advanced Light Source (ALS) is receiving support from the Gordon and Betty Moore Foundation in the amount of $2.4 million. The grant was in April by the foundation. The lead investigator on the effort will be ALS Division Deputy Zahid Hussain with ALS Director Roger Falcone acting as co-PI on the project.

The Moore Foundation awarded the funding for the development of a new spectrometer for studying materials using X-ray scattering. The citation reads: “In support of research targeting the development of novel x-ray scattering instrumentation for probing quantum materials.”

The grant is part of the Moore Foundation’s Emergent Phenomena in Quantum Systems (EPiQS) Initiative, which “strives to deepen our understanding of the complex collective behavior electrons exhibit in materials and engineered structures.”

The $2.4M will be over a 5-year period.

To understand the emergent physical rules that quantum materials follow, one needs powerful tools to manipulate the entangled structures. This newly designed instrument will make far more efficient use of synchrotron X-rays and advance the state of the art in energy resolution. It will also increase the number of material systems that can be studied.

“The Gordon and Betty Moore Foundation has recognized that the field of quantum materials is of increasing importance for both fundamental science and new technologies,” said ALS Director Falcone. “At the ALS we’re very pleased that the Foundation is supporting the development of a globally unique instrument for inelastic x-ray scattering, which will provide extraordinary new insight into these materials, allow tailoring of functional properties, and support leading scientists from around the nation and the world in their work in this field. I have no doubt that amazing and important discoveries will result from this partnership between Berkeley Lab and the Moore Foundation.”

This research is funded in part by the Gordon and Betty Moore Foundation EPiQS Initiative, Grant 4630 to Berkeley Lab. Support also comes from the Department of Energy’s Office of Science.

(Initially issued as news release from Berkeley Lab Public Affairs)

Elaine Chan Fosters ALS/Molecular Foundry Collaboration Print

In an ongoing effort to build closer working relationships between Berkeley Lab’s light source and nanoscale science research center, Elaine Chan has recently been appointed by the ALS and the Molecular Foundry to a new role as joint ALS/Foundry project scientist. Chan’s mission will be to foster collaborations between the two facility’s users and to communicate a wider understanding about how the two research centers are mutually scientifically beneficial.

Chan has a background in nanoscale science and has worked for four years at ALS Beamline 7.3.3, a beamline that’s hosted many Foundry users and is uniquely suited to serve the needs of ALS/Foundry research. One of the capabilities of Beamline 7.3.3 is high-throughput x-ray scattering characterization of materials, which complements the high-throughput chemical syntheses of the novel materials produced by the Foundry.

Chan’s efforts will be focused on communicating with users and coordinating scientific collaboration. To that end, she’ll begin with the launch of a seminar series at the Molecular Foundry called ALS School, which will bring ALS scientists to the Foundry user community on a regular basis to “teach” them about how various ALS capabilities can advance their science. Likewise, a similar seminar series for Foundry scientists to teach the ALS user community about their materials characterization challenges is in the works. Chan has also envisioned a new joint ALS–Foundry user highlight series that would showcase the work of ALS and Foundry users. A joint webpage that would disseminate information and showcase the highlights and the seminars is also in the works.

“The seminar series will really be our first push,” Chan says. “We’d like to sort of do away with some of the mystery of what happens at the ALS; really communicate at a basic level how the facility can serve both sets of users.”

Chan will also be working closely with Foundry users at ALS Beamline 7.3.3 to make photon science experiments more user-friendly and productive.  She will be assisting Foundry users with high-throughput scattering measurements of their materials.  Chan is also developing software interfaces for the beamline endstation in order to better streamline the high-throughput experimental set-ups and to facilitate the interpretation of the scattering data.

Chan notes that joint ALS/Foundry publications have been increasing steadily for the past four years, with about 25 percent of those publications coming from Beamline 7.3.3 on the ALS side. Over the last year, 16 percent of all Foundry user publications involve joint work with a variety of beamlines at the ALS.  Chan believes that there are even more potential opportunities for the two user facilities to partner, and she’s excited to help them become realized.

2015 ALS Shutdown Print

The upcoming long-term operating schedule has been published and users will note that it includes an extended shutdown period (October 26, 2015-January 13, 2016) for the ALS. The lengthy shutdown is in part because it spans the Thanksgiving and Holiday shutdown periods, as well as being indicative of the amount of time required to implement major upgrades. The main project for this shutdown is the Storage Ring Radio Frequency (SRRF) Upgrade. This is the final phase of this many-year effort to provide more RF power that will be required for the use of additional insertion devices, and to create a robust back-up system. We have already replaced our long-lived klystron, the RF high-voltage power supply, and the high-voltage RF switch in prior shutdowns.  While the ALS reliably operated on this new equipment, a second klystron was also installed. This last phase installs a "switch matrix" RF wave guide, which in its nominal state will provide each ALS storage ring RF cavity with RF from a single klystron. In the event of a klystron failure in the future, we will be able to redirect RF from either klystron to either cavity in the matter of hours rather than the many days it would take to swap out and commission a spare klystron.

The other major activity planned for this shutdown is installing the very first non-evaporable-getter(NEG)-coated vacuum chamber in the ALS. This is new technology for the ALS, and is very exciting since it will enable the small gap insertion device required to meet the carbon edge on the new COSMIC beamline in sector 7.  While there are many other accelerator activities planned, these are the major shutdown projects.

In order to maintain and expand ALS capabilities for users, the last couple of years have been an extensive period of renewal and upgrades including Top Off, the Sextupole Upgrade (low-emittance lattice), the RF Upgrade, the Instrumentation and Controls Upgrade, and the chicaning of sector 7  for the MAESTRO and COSMIC beamlines. The next couple of major shutdowns will focus on changes required to create the space needed in sector 2 of the accelerator for the Howard Hughes Medical Institute funded Gemini insertion device and the installation of the Gemini beamline front-end.

Beamline work for this upcoming shutdown has not yet been detailed, but work requests are already being submitted. Staff and users are asked to contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it as soon as possible with work requests planned for the shutdown.

Reflections on our Past, Present, and Future Print

Reflecting on 2014, I’d first point to our impressive science (see many highlights on the webpage, and a record number of users and publications: the ALS supported over 2,400 users and we expect to exceed our 2013 record of more than 800 publications. Of course, the past year was also a challenging one for us; together with other national facilities, we had to reduce staff due to reduced government funding. While there is still uncertainty about what the next few years hold for broad government support of science, funding for us this year is now secure and we are well positioned to take advantage of resources as we go forward.

After visiting the ALS and talking with beamline scientists, DOE Secretary Ernest Moniz toured the facility with ALS Director Roger Falcone.

This year is a good time for ALS to both focus on its core strengths and expand partnerships—with other divisions at LBNL, new research programs, other national laboratories, and new funding sources, including foundations. We have an ambitious set of beamline and instrument projects planned for the next few years, and we’ll be able to accomplish our goals with support from those new funding sources.

This year will see the completion of the MAESTRO nano-ARPES beamline, and the COSMIC imaging and scattering project will move forward towards a 2016 completion date. Two new beamlines—AMBER and QERLIN—are in early-stage development and should be completed within the next few years. These projects are key to the future of the ALS in various research areas, including renewable energy sciences and quantum materials. Additional projects include the upgrade of existing beamlines—SAX-WAX (together with the Molecular Foundry), small molecule crystallography, spin-ARPES, ambient pressure photoemission (in support of the energy hubs JCAP and JCESR), and scattering in the so-called “tender” x-ray regime (supported by LDRD funds). Beyond that, we’re also working with Howard Hughes Medical Foundation to complete a world-leading micro-focus beamline for structural biology.

In the next few years, we look forward to supporting users with these new capabilities, which will keep us on the cutting edge of science. Also, these projects are consistent with our long-term desire to upgrade the ALS storage ring to fully utilize diffraction-limited or highly coherent x-rays. Together with our community, we’re continuing to examine the opportunities that would be made available with such a brightness upgrade. Also, it is important that instruments we build over the next few years be upgradable for “ALS-U” operations, since we see that as the future for our facility.

Support from Basic Energy Sciences at DOE, together with contributions from our partners, is helping us to operate optimally for users and move forward with our project priorities. We will continue to demonstrate how ALS can increase scientific productivity across a broad spectrum of science and technology, and contribute to the technical and economic vibrancy of the nation.

ALS Director Roger Falcone talked about the power of new nanoscale imaging techniques at the 2014 User Meeting.

I am very proud that in the past year we significantly expanded our relationship with the computing divisions at the Lab. As the brightness of our storage ring and the number of ALS instruments has increased over more than 20 years of operation, so have the number of users, experiments, and rate of data generation. Dealing with enormous amounts of data has become increasingly important to the future of the ALS and the Lab as a whole. The Computing Research Division and NERSC computing facility are playing a key role in helping us manage this data, and together we have developed a nationally recognized capability and reputation for rapidly processing huge amounts of data, benefiting users both at the ALS and related facilities.

People at ALS are of course the reason for our success, and I’m pleased to welcome Scott Taylor as safety coordinator and newest member of our ALS family. With Scott’s past experience here at LBNL, and ALS’s Jim Floyd’s promotion to director of the Lab’s EHS Division, we’re well positioned to continue as a model for a great safety culture.

It’s going to be a fun and productive year!

Contact: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

ALS Workshop Highlights Diffraction-Limited Storage Ring Opportunities Print

workshopOn October 1-3, 2014, the ALS hosted a workshop on Soft X-Ray Science Opportunities Using Diffraction-Limited Storage Rings. The workshop charge was to elaborate transformational research opportunities that would be enabled by emerging storage-ring-based ultrahigh brightness soft and intermediate x-ray beams, and to examine the primary challenges needed to accomplish these opportunities. More than scientists from around the world attended the workshop and set a very enthusiastic tone throughout the three-day period.

The first morning of the workshop started off with plenary talks covering material and biological science opportunities as well as the potential capabilities of high-brightness accelerators. These talks were followed by nine energetic short talks by staff from facilities around the world that described techniques and research opportunities enabled by high-source brightness and the resulting diffraction-limited beams. These talks formed the basis for 13 separate breakout sessions over the following two days that focused on quantum materials, magnetic materials, low power information processing, energy science and catalysis, chemical and materials excitations, fluctuations, and dynamics, biological science, soft condensed matter, and environmental science. These were scheduled so that attendees could move from one subject thread to another to gain a wider appreciation of scientific opportunities.  Much time for discussion of science ideas was provided, both during the breakouts and also after each session, ensuing a healthy "flux" of ideas among attendees. This cross-fertilization was both fun and challenging, inspiring outside-the-box thinking and new collaborations.

Leaders of the breakout sessions, facilitated by ALS staff, are already drafting a workshop report with chapters on the various subjects noted above. The document should be available to the broad community by the end of 2014.

See photos of the event here: Looking at the Future of Soft X Ray Science

Notification of General User Proposal Results 2015-1 Print

The Proposal Study Panel met on October 20 to oversee and finalize the scoring of all General User Proposals for the 2015-1 (January–June) operating cycle. Allocation meetings for each beamline are now taking place, and the results of the review are expected to be released to ALS users around mid-November.

The mechanism for notifying users of their proposal results will be different from previous cycles. Each principal investigator and experiment leader, who have submitted one or more proposals, will be sent a single email inviting them to login to ALSHub, the ALS user portal, to view the outcome of the review and allocation of beam time. This replaces the previous mechanism of sending a separate email for each proposal.


What will you see in ALSHub?

Users will be able to see their proposals submitted this cycle as well as submissions from previous cycles. The status will indicate ‘Review completed’ for the new proposals submitted for this cycle. Proposals from previous cycles will have a status of ‘Active’ or ‘Expired’.

To view the results of the review for each proposal, users will need to click on the Experiment ID. An example of what is displayed is shown below.

Staff in the user office, particularly This e-mail address is being protected from spambots. You need JavaScript enabled to view it , the proposal coordinator, and This e-mail address is being protected from spambots. You need JavaScript enabled to view it are available throughout this process to answer user queries, and help you. Do not hesitate to contact them for advice, or login to ALSHub to check on the progress of your proposals.

gup notifications

Diffraction-Limited Soft X-Ray Workshop Print

On October 1–3, 2014, the ALS hosted a workshop entitled Soft X-Ray Science Opportunities Using Diffraction-Limited Storage Rings. The workshop charge was to determine transformational research opportunities enabled by emerging storage-ring-based ultrahigh brightness soft and intermediate x-ray beams, and to examine the primary challenges to accomplish these opportunities. More than 80 scientists from around the world attended the workshop and set a very enthusiastic tone throughout the entire three-day period.

The first morning of the workshop started off with three plenary talks on material and biological science opportunities, and on the capabilities of high- brightness accelerators. These presentations were followed by nine energetic short talks by staff from facilities around the world, which described techniques and research opportunities enabled by high source brightness and the resulting diffraction-limited beams.  These talks formed the basis for 13 separate breakouts over the following two days focused on quantum materials, magnetic materials, low power information processing, energy science and catalysis, chemical and materials excitations, fluctuations, and dynamics, biological science, soft condensed matter, and environmental science.  These were scheduled so that attendees could move from one subject thread to another.  Much time for discussion of science ideas was provided, both during the breakouts and also after each session, to ensure a healthy flux of ideas among all attendees.  This cross-fertilization was fun and led to a healthy cross-fertilization and outside-the-box thinking.

Breakout leads, facilitated by ALS staff, are already drafting a workshop report with chapters on the various subjects noted above.  This should be available to the broad community by the end of 2014.

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