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Knowledge of the chemical speciation of particulate manganese (pMn) is important for understanding the biogeochemical cycling of Mn and other particle‐reactive elements. Here, we present the synchrotron‐based X‐ray spectroscopy‐derived average oxidation state (AOS) of pMn in the surface Arctic Ocean collected during the United States GEOTRACES Arctic cruise (GN01) in 2015. We show that the pMn AOS is <2.4 when sampled during the day and more than ∼3.0 when sampled at night. We hypothesize that an active light‐dependent redox cycle between dissolved Mn and particulate Mn(III/IV) exists during the day‐night cycle in the surface Arctic Ocean, which occurs on the timescale of hours. The magnitude of observed pMn AOS is likely determined by the net effect of the length of the previous night and integrated light level before the end of pMn sampling. Plain Language Summary: Manganese (Mn) exists in three oxidation states (II, III, and IV) in the ocean. The difference in oxidation states of Mn minerals leads to differences in their capacities to oxidize and sorb other elements, and thereby affects their role in marine redox and nutrient cycling. In this study, we measured the oxidation states of marine particulate Mn in the surface Arctic Ocean. Our results demonstrate a tight coupling between sunlight and particulate Mn oxidation states: more Mn(II) exists in the daytime, whereas more Mn(III/IV) exists during the night. The light‐dark cycle is an important driver in the rapid transition between Mn(II) and Mn(III/IV). Key Points: Particulate manganese oxidation states are more reduced in the day and more oxidized at night in the surface Arctic OceanThe Mn diel cycle results from the conversion between dissolved Mn and particulate Mn(III/IV) oxides regulated by lightThe length of night and intensity of light exposure are two main controls on the magnitude of particulate Mn average oxidation states [ABSTRACT FROM AUTHOR]

Phosphorus deficiency and excess are concomitant problems in agricultural soils of the mid‐Atlantic region. A fundamental understanding of soil P speciation is essential to assess P fate and transport in these soils. Current methods for soil P speciation often rely on sequential chemical extractions, which can introduce artifacts during analysis. To overcome limitations of current methods, this study evaluated synchrotron‐based micro‐focused X‐ray fluorescence (µ‐XRF) and X‐ray absorption near‐edge spectroscopy (µ‐XANES) techniques to assess soil P speciation in agricultural soils collected from the mid‐Atlantic region of the United States. Three soils with varying chemical and physical properties were analyzed with µ‐XRF maps collected at high (12,000 eV) and tender (2240 eV) energies to evaluate colocation of P with Fe, Al, Ca, and Si in soil samples, and µ‐XANES spectra were collected at the P K‐edge for P hotspots. Combined µ‐XRF and µ‐XANES analysis was useful for identifying Ca phosphate, Fe phosphate, Al‐sorbed P, and Fe‐sorbed P species in heterogeneous soil samples. X‐ray fluorescence maps were valuable to distinguish Al‐oxide sorbed P from Fe‐oxide sorbed P species. A low signal‐to‐noise ratio often limited µ‐XANES data collection in regions with diffuse, low concentrations of P. Therefore, some P species may not have been detected during analysis. Even with varying degrees of self‐absorption and signal‐to‐noise ratios in µ‐XANES spectra, important inferences regarding P speciation in mid‐Atlantic soils were made. This study highlights the potential of µ‐XANES analysis for use in environmental and agricultural sciences to provide insights into P fate and transport in soils. [ABSTRACT FROM AUTHOR]

Over the past few years, research carried out at large-scale materials science facilities in the USA and elsewhere has undergone a phase transition that affected its character and culture. Research cultures at these facilities now resemble ecosystems, comprising of complex and evolving interactions between individuals, institutions, and the overall research environment. The outcome of this phase transition, which has been gradual and building since the 1980s, is known as the New (or Ecologic) Big Science [Crease, R. and Westfall, C. (2016). The new big science. Physics Today , 69: 30–6]. In this article, we describe this phase transition, review the practical challenges that it poses for historians, review some potential digital tools that might respond to these challenges, and then assess the theoretical implications posed by "database history'. [ABSTRACT FROM AUTHOR]

Purpose: Only few centers worldwide treat intraocular tumors with proton therapy, all of them with a dedicated beamline, except in one case in the USA. The Italian National Center for Oncological Hadrontherapy (CNAO) is a synchrotron‐based hadrontherapy facility equipped with fixed beamlines and pencil beam scanning modality. Recently, a general‐purpose horizontal proton beamline was adapted to treat also ocular diseases. In this work, the conceptual design and main dosimetric properties of this new proton eyeline are presented. Methods: A 28 mm thick water‐equivalent range shifter (RS) was placed along the proton beamline to shift the minimum beam penetration at shallower depths. FLUKA Monte Carlo (MC) simulations were performed to optimize the position of the RS and patient‐specific collimator, in order to achieve sharp lateral dose gradients. Lateral dose profiles were then measured with radiochromic EBT3 films to evaluate the dose uniformity and lateral penumbra width at several depths. Different beam scanning patterns were tested. Discrete energy levels with 1 mm water‐equivalent step within the whole ocular energy range (62.7–89.8 MeV) were used, while fine adjustment of beam range was achieved using thin polymethylmethacrylate additional sheets. Depth‐dose distributions (DDDs) were measured with the Peakfinder system. Monoenergetic beam weights to achieve flat spread‐out Bragg Peaks (SOBPs) were numerically determined. Absorbed dose to water under reference conditions was measured with an Advanced Markus chamber, following International Atomic Energy Agency (IAEA) Technical Report Series (TRS)‐398 Code of Practice. Neutron dose at the contralateral eye was evaluated with passive bubble dosimeters. Results: Monte Carlo simulations and experimental results confirmed that maximizing the air gap between RS and aperture reduces the lateral dose penumbra width of the collimated beam and increases the field transversal dose homogeneity. Therefore, RS and brass collimator were placed at about 98 cm (upstream of the beam monitors) and 7 cm from the isocenter, respectively. The lateral 80%–20% penumbra at middle‐SOBP ranged between 1.4 and 1.7 mm depending on field size, while 90%–10% distal fall‐off of the DDDs ranged between 1.0 and 1.5 mm, as a function of range. Such values are comparable to those reported for most existing eye‐dedicated facilities. Measured SOBP doses were in very good agreement with MC simulations. Mean neutron dose at the contralateral eye was 68 μSv/Gy. Beam delivery time, for 60 Gy relative biological effectiveness (RBE) prescription dose in four fractions, was around 3 min per session. Conclusions: Our adapted scanning proton beamline satisfied the requirements for intraocular tumor treatment. The first ocular treatment was delivered in August 2016 and more than 100 patients successfully completed their treatment in these 2 yr. [ABSTRACT FROM AUTHOR]

Abstract: An attractive feature of neutron techniques is the ability to identify hidden materials and structures inside engineering components and objects of art and archaeology. Bearing this in mind we are investigating a new technique, “Tomography Driven Diffraction” (TDD), that exploits tomography data to guide diffraction experiments on samples with complex structures and shapes. The technique can be used utilising combinations of individual tomography and diffraction instruments, such as NEUTRA (PSI, CH) and ENGIN-X (ISIS, UK), but is also suitable for new combined imaging and diffraction instruments such as the JEEP synchrotron engineering instrument (DIAMOND, UK) and the proposed IMAT neutron imaging and diffraction instrument (ISIS, UK). [Copyright &y& Elsevier]

Abstract: We present measurements and model calculations of fluence and linear energy transfer in water () obtained using 56Fe beams with 1GeV/amu kinetic energy incident on aluminum, polyethylene, PMMA, and lead targets. The measured spectra are compared to predictions of the PHITS model. The study is motivated by NASA''s need to develop accurate heavy ion transport codes to assess radiation exposures in deep space, where galactic cosmic rays are important. The data were obtained at the Alternating Gradient Synchrotron at the Brookhaven National Laboratory. Distributions of charge and LET depend on the depth and composition of the target. Several of the targets studied are “thick”, defined operationally as a depth that presents at least 50% of an interaction length to the beam ions. In a thick target, the probability of a secondary interaction is significant, tertiary interactions can also be important, and the target-exit fluence and charge distributions depend on unmeasured cross sections that can only be estimated by nuclear interaction models. Comparisons between calculated and measured spectra are therefore of considerable interest. Some targets used in the study are thin, so that secondary and higher interaction probabilities are negligible, allowing more stringent comparisons between the data and the model. We find that PHITS reproduces some aspects of the experimental data well, but fails to accurately reproduce many of the measured fragment fluences. [Copyright &y& Elsevier]

As Brookhaven aligns key scientific facilities and tools meant to make it a leader in U.S. energy research, government and Lab officials say the time has come to fight for and secure the last piece of the puzzle - the National Synchrotron Light Source II (NSLS-II). Held in conjunction with the official opening of the Center for Functional Nanomaterials (CFN), the second joint meeting of the National Synchrotron Light Source (NSLS) and CFN user communities stressed the importance of NSLS-II to the Lab's research synergy. [ABSTRACT FROM AUTHOR]

The present Alternating Gradient Synchrotron (AGS) injection kicker magnets at the A5 location were designed for 1.5 GeV proton injection. Recent high intensity runs have pushed the transfer kinetic energy to 1.94 GeV, but with an imperfect matching in transverse phase space. Space charge forces result in both fast and slow beam size growth and beam loss. A proposed increase in the AGS injection energy to 2 GeV with adequate kick strength would greatly reduce the beam losses making it possible to increase the intensity from 70 TP (70 × 1012 protons/s) to 100 TP. R&D studies are being undertaken by TRIUMF, in collaboration with Brookhaven National Laboratory (BNL), to design two new kicker magnets for the AGS A10 location to provide an additional kick of 1.5 mrad to 2 GeV protons. The kick strength rise and fall time specifications are 100 ns, 3% to 97%; the design goal is to achieve a field uniformity, for protons, of ±3% over 90% of the cross-sectional area of the aperture. TRIUMF has proposed a design for a 12.5 Ω transmission line kicker magnet powered by a matched 12.5 Ω pulse forming line. This paper presents the results of detailed 2D and 3D electromagnetic modeling of the kicker magnet, and a novel mathematical model of the kicker. [ABSTRACT FROM AUTHOR]

Chemical speciation determines Se solubility and therefore its bioavailability and potential for transport in the environment. In this study we investigated the speciation of Se in soil developed on reclaimed mine sites in the U.S. Western Phosphate Resource Area (WPRA) using micro-X-ray absorption near-edge structure (μ-XANES) spectroscopy and micro-X-ray fluorescence (μ-XRF) mapping. Selenium was nonuniformly distributed in the soils and positively correlated with Fe, Mn, Cu, Zn, and Ni. Sixteen points of interest (POI) from three soil samples were analyzed with μ-XANES spectroscopy. The XANES data indicated that Se is present in the soils in at least three oxidation states, Se(-II, 0), Se(IV), and Se(VI). Selenides or elemental Se dominated 7 of the 16POI. Selenate was the dominant species at only one of the POI. The remaining eight POI were composed of both Se(IV) and Se(VI), with minor Se(-II, 0) contributions. The results of this research suggest that the reduced Se species in the soil parent material are oxidizing to Se(VI), one of the more mobile species of Se in the environment. This information can be used to better predict and manage Se availability in soils. [ABSTRACT FROM AUTHOR]

Highlights the Cornell High Energy Synchrotron Source's (CHESS) Sixteenth annual Users Meeting in Clark Hall at Cornell University in Ithaca, New York on June 24-25, 2003. Developments in microcrystallography, Laue diffraction with multiplayer optics, robotic sample transfer and the use of small-angle scattering to help constrain phases in crystallographic data analysis; Review of X-ray beam position monitoring; Improvements to CHESS computing facilities.

Reports on the operational principles and fundamental parameters at the Synchrotron Ultraviolet Radiation Facility in the U.S. Use of synchrotron radiation for metrology; Improvement of the radio-frequency system; Construction of a compact synchrotron radiation light sources.

Reports on the advancement at the European Synchrotron Radiation Facility in the U.S. Characteristics and parameters of the electron beam; Beamline safety in terms of radioprotection; Installation of a number and variety of insertion devices in the straight sections of the storage ring.

Reports on the 29th annual users meeting of the Stanford Synchrotron Radiation Laboratory (SSRL) in the U.S. in October 2002. Dynamic forum for the presentation and discussion of research activities from the SSRL and the synchrotron community; Range of issues and subject matter addressed by the meeting; Implications on the synchrotron community.

A commercial Nicolet Magna-IR series rapid-scan Michelson Fourier transform infrared was installed in a vacuum housing and integrated into the U4IR beamline at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The frequency reference laser was mounted outside the vacuum, but the moving mirror mechanism and the dynamic alignment system for the fixed mirror were in a vacuum. The performance of the instrument was measured in the usual way by measuring the repeatability of data collected under specific conditions of aperture, resolution, and mirror scanning velocity. We briefly discuss the beamline design, to put the interferometer in context, then present signal to noise data which we discuss in terms of both instrument performance and also storage ring beam stability. Under optimal conditions, the instrument has a reproducibility of 0.01% in 1 min of measuring time at a resolution of 2 cm-1, over a range from 100–3000 cm-1. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The current status of the Louisiana State University Center for Advanced Microstructures and Devices electron storage ring, beamlines, and the scientific program are described. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents the three dimensional designs of the Ultra Compact Synchrotron (UCS) Vobly dipole proposed for the University of California, Los Angeles. Description of the UCS; Magnetic behavior of a Vobly type of dipole as a conventional water cooled iron dominated dipole.

Reports on the decision of the U.S. government to allot a budget for the establishment of synchrotron radiation centers. Estimated value of the budget; Recommendations of the Panel to Asses the National Need for Facilities Dedicated to the Production of Synchrotron Radiation; Details on the facility.

The use of accelerated ions for the removal of localized tumors without surgery has seen a wide development in the U.S., Japan, and Europe. Today new sites are under construction and some kind of competition has started to design and build the most versatile and/or the most cost effective facility. Developments like the laser ion source, which can create more than enough carbon ions in charge state 6, the electron beam ion source with ultrashort ion extraction and the rapid cycling medical synchrotron may contribute to reduce the investment cost as well as the cost per treatment. [ABSTRACT FROM AUTHOR]

This article reports that shifting priorities and the expectation of worsening budgets have triggered layoffs at two U.S. synchrotron facilities in California. Officials at the Department of Energy's (DOE's) Advanced Light Source at Lawrence Berkeley National Laboratory and the Stanford Synchrotron Radiation Laboratory say the cutbacks, which include shutting down one beamline at each facility, are necessary to free up money for new projects, such as brighter beams. The cuts may not be reversed managers say, even if Congress beefs up the lean 2006 DOE budget proposed by U.S. President George W. Bush Administration. The two labs are funded by DOE's 1.1 billion dollars Office of Basic Energy Sciences, which received a 41 million dollars boost in the president's request for 2006. But that 4% increase includes 151 million dollars in new funds to expand nanoscale research facilities and begin work on the Linac Coherent Light Source at Stanford and a high-flux neutron beam under construction in Oak Ridge, Tennessee, the pair of which should benefit physicists, doctors, and chemists.

Highlights the Environmental Sciences Workshop at the National Synchrotron Light Source Users' Meeting in Upton, New York. Use of synchrotron facilities to investigate processes controlling chemical species in the environment; Applications of synchrotron based techniques; Overview of metal binding on different sites on humic acids from various sources.

Focuses on job opportunities for physicists willing to work with biologists in the field of structural genomics in the United States. Details of an initiative by the National Institute of General Medical Sciences for deciphering the three-dimensional shapes of proteins; Labor market demand for people with multidisciplinary skills to operate beamlines in synchrotrons. INSET: Wages make it hard to attract scientists to synchrotrons.

States that a key federal panel recommended continued research toward a `fourth generation' synchrotron, a machine capable of creating x-ray pulses billions of times more intense than current designs. Request of the United States Department of Energy for advice from the panel on how to proceed with novel synchrotrons; Proposal of several designs; Importance of the panel's endorsement.

Focuses on the applications of contact x-ray microscopy in the United States. Use of x-ray sources and high magnification of an electron microscope; Procedure on contact x-ray microscopy; Availability of synchrotron as source for soft x rays.

Discusses issues related to government funding of four synchrotrons in the United States. Funding from the Department of Energy (DOE); Low priority of the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory, California; Tripling of support for synchrotrons in past decade; Recommendation for funding increase; Facilities with highest priorities; Conversion of older facilities; Reasons for ALS' low priority; Support for synchrotrons.

Discusses recommendations made by a US Department of Energy panel reviewing synchrotron research facilities. Questions about the Advanced Light Source (ALS) at Lawrence Berkeley National Lab, California; Status of other labs; Panel asked to recommend priorities for synchrotron radiation research; Panel's solutions; Problems and costs at ALS; Panel not recommending closing ALS.

Announces that the prospect of level spending through 2002 has led the US Department of Energy to examine the fate of its four synchrotron facilities as of August 1997. Breakdown of the costs of the four facilities; Advanced Light Source; National Synchrotron Light Source; Synchrotron Radiation Laboratory; Advanced Photon Source; Comments from officials. INSET: Industry chafes at APS rules..

The article reports on the decision of U.S. physicists to completely rebuild the particle accelerator of the Advanced Photon Source (APS) at Argonne National Laboratory in Lemont, Illinois. The rebuild is expected to result in incremental improvements to the synchrotron that generates the x-rays. The estimated cost of the earlier proposed upgrade is 391 million dollars.

The article reports on the construction development of the National Synchrotron Light Source II (NSLS-II) storage ring at Brookhaven National Laboratory in the U.S. It notes that the NSLS-II ring will house the accelerator ring after it has been completed. It mentions that the steel beams will be arriving on the site early in September 2009, and will begin steel erection in December 2009. It also mentions that the engineering design of the magnet girder has been tested for development.

The article introduces the Ultra High-Precision Slits Catalog, a listing of new design and innovation in synchrotron equipment, designed by Advanced Design Consulting USA Inc. in the U.S. The 32-page material, which is essential to astrophysicists, offers information about blade polishing, blade accuracy and repeatability, and blade parallelism.

Reports on the Advanced Photon Source project in Argonne, Illinois. Support of the U.S. National Institute of General Medical Sciences for the project; Accomplishments of physicist Ronald Ruth in the project; Facts about the generation of high-energy X-rays by synchrotrons;

Focuses on the reliance of investigators at the United States National Institutes of Health (NIH) on large scientific facilities. Maintenance of the large facilities by the United States Department of Energy (DoE); Willingness of the NIH to help equip some of the DoE's synchrotrons.

Reports on the plan of the United States Department of Energy to boost the budget of Advanced Light Source (ALS), a premier synchrotron at the Lawrence Berkeley National Laboratory in California. Background of the research program of ALS; Why the DOE cut its budget; Reorganization initiated by Lawrence Berkeley leaders; Details on the scientific productivity of ALS.

Reports on a recommendation by the Nuclear Science Advisory Committee's (NSAC's) Kaon subcommittee, to consider US participation in building a kaon factory, to produce K mesons, near Vancouver, British Columbia. The report states NSAC's intention to study the kaon factory later as part of its new long-range plan; Brookhaven Alternating Gradient Synchrotron; Neutron densities within nuclei; Canada's TRIUMF cyclotron.

Reports on the flaws found in the proposed National Center for Advanced Materials at Lawrence Berkeley Laboratory by a panel appointed by the U.S. Department of Energy to review the project in 1983. Criticism of the relevance of the project's synchrotron light source; Lack of customary peer review for the proposal; Arguments of the panel.

Reports on the plan of Cornell University in Ithaca, New York to convert its Wilson Laboratory synchrotron facility into an electron storage ring. Maximum design luminosity of the storage ring; Details of the construction and design of the storage ring; Information on the technique called vernier phase-space compression developed at Cornell which will be used in the storage ring.

Early stage experimental data in structural biology is generally unmaintained and inaccessible to the public. It is increasingly believed that this data, which forms the basis for each macromolecular structure discovered by this field, must be archived and, in due course, published. Furthermore, the widespread use of shared scientific facilities such as synchrotron beamlines complicates the issue of data storage, access and movement, as does the increase of remote users. This work describes a prototype system that adapts existing federated cyberinfrastructure technology and techniques to significantly improve the operational environment for users and administrators of synchrotron data collection facilities used in structural biology. This is achieved through software from the Virtual Data Toolkit and Globus, bringing together federated users and facilities from the Stanford Synchrotron Radiation Lightsource, the Advanced Photon Source, the Open Science Grid, the SBGrid Consortium and Harvard Medical School. The performance and experience with the prototype provide a model for data management at shared scientific facilities.

For the last six years, the Macromolecular Crystallography Research Resource (PXRR) has been providing mail-in access to several beamlines at the National Synchrotron Light Source (NSLS) for X-ray diffraction. This program is available at no charge for academic users from the US and around the world. This service has fostered a new paradigm for collaborations between the local staff scientists and synchrotron users. It also accelerates the innovation of new productivity tools, which benefit users who come to NSLS beamlines as well as those who use the mail-in program.

This paper reports results from the first biological crystal-growth experiment on the International Space Station (ISS). Crystals of thaumatin were grown using liquid-liquid diffusion in Tygon tubing transported in the Enhanced Gaseous Nitrogen Dewar (EGN). Different volume ratios and concentrations of protein and precipitant were used to test different adaptations of the vapor-diffusion crystallization recipe to the liquid-liquid diffusion method. The EGN warmed up from 77 to 273 K in about 4 d, about the same time it took to warm from 273 to 293 K. The temperature within the EGN was 293-297 K for the majority of the experiment. Air gaps that blocked liquid-liquid diffusion formed in the tubes. Nonetheless, crystals were grown. Synchrotron diffraction data collected from the best space-grown crystal extended to 1.28 A, comparable to previous studies of space-grown thaumatin crystals. The resolution of the best ground-control crystal was only 1.47 A. It is not clear if the difference in diffraction limit arises from factors other than crystal size. Improvements in temperature control and the elimination of air gaps are needed, but the results show that the EGN on the ISS can be used to produce space-grown crystals that diffract to high resolution.

Research at synchrotron radiation facilities, once the domain of high energy physics, now has a major impact on fields as diverse as immunology, neurobiology, physiology, molecular biology, medicine and biotechnology. This article describes the development of a comprehensive synchrotron portal and informational website (http://www.biosync.sdsc.edu) for biologists engaged in research at synchrotrons. The site automatically provides timely and accurate information in a unified format by gathering technical descriptions of synchrotron beamlines using modern information management practices.