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Journal of Synchrotron Radiation

Simon R Larsen, Marie Hansteen, Barbara Pacakova, Keld Theodor, Thomas Arnold, Adrian R Rennie, Geir Helgesen, Kenneth D Knudsen, Heloisa N Bordallo, Jon Otto Fossum, Leide P Cavalcanti
Commissioning results of a liquid sample cell for X-ray reflectivity studies with an in situ applied electrical field are presented. The cell consists of a Plexiglas container with lateral Kapton windows for air-liquid and liquid-liquid interface studies, and was constructed with grooves to accept plate electrodes on the walls parallel to the direction of the beam. Both copper and ITO plate electrodes have been used, the latter being useful for simultaneous optical studies. Commissioning tests were made at the I07 beamline of the Diamond Light Source...
May 1, 2018: Journal of Synchrotron Radiation
Nelly R Hajizadeh, Daniel Franke, Dmitri I Svergun
The versatility of small-angle X-ray scattering (SAXS) as a structural biology method is apparent by its compatibility with many experimental set-ups. Most advanced SAXS studies are conducted at dedicated synchrotron beamlines yielding high beam brilliance, throughput and temporal resolution. However, utilizing the full potential of the method while preserving a high degree of automation provides a challenge to any SAXS beamline. This challenge is especially pertinent at the P12 BioSAXS beamline of the EMBL at the PETRAIII Synchrotron DESY (Hamburg, Germany), optimized and dedicated to scattering of macromolecular solutions...
May 1, 2018: Journal of Synchrotron Radiation
Patric Zimmermann, Robert J Green, Maurits W Haverkort, Frank M F de Groot
Some initial instructions for the Quanty4RIXS program written in MATLAB® are provided. The program assists in the calculation of 1s 2p RIXS and 1s 2p RIXS-MCD spectra using Quanty. Furthermore, 1s XAS and 2p 3d RIXS calculations in different symmetries can also be performed. It includes the Hartree-Fock values for the Slater integrals and spin-orbit interactions for several 3d transition metal ions that are required to create the .lua scripts containing all necessary parameters and quantum mechanical definitions for the calculations...
May 1, 2018: Journal of Synchrotron Radiation
Ulrike Boesenberg, Christopher G Ryan, Robin Kirkham, Andreas Jahn, Anders Madsen, Gareth Moorhead, Gerald Falkenberg, Jan Garrevoet
A new fast X-ray absorption spectroscopy scanning method was recently implemented at the Hard X-ray Microprobe endstation P06, PETRA III, DESY, utilizing a Maia detector. Spectromicroscopy maps were acquired with spectra for X-ray absorption near-edge structure (XANES) acquisition in the sub-second regime. The method combines XANES measurements with raster-scanning of the sample through the focused beam. The order of the scanning sequence of the axes, one beam energy axis and two (or more) spatial axes, is a variable experimental parameter and, depending on it, the dwell at each location can be either single and continuous (if the energy axis is the inner loop) or in shorter discontinuous intervals (if a spatial axis is innermost)...
May 1, 2018: Journal of Synchrotron Radiation
David Aragão, Jun Aishima, Hima Cherukuvada, Robert Clarken, Mark Clift, Nathan Philip Cowieson, Daniel Jesper Ericsson, Christine L Gee, Sofia Macedo, Nathan Mudie, Santosh Panjikar, Jason Roy Price, Alan Riboldi-Tunnicliffe, Robert Rostan, Rachel Williamson, Thomas Tudor Caradoc-Davies
MX2 is an in-vacuum undulator-based crystallography beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the energy range 4.8-21 keV to a focal spot of 22 × 12 µm FWHM (H × V). At 13 keV the flux at the sample is 3.4 × 1012  photons s-1 . The beamline endstation allows robotic handling of cryogenic samples via an updated SSRL SAM robot. This beamline is ideal for weakly diffracting hard-to-crystallize proteins, virus particles, protein assemblies and nucleic acids as well as smaller molecules such as inorganic catalysts and organic drug molecules...
May 1, 2018: Journal of Synchrotron Radiation
Hyun Joon Shin, Namdong Kim, Hee Seob Kim, Wol Woo Lee, Chae Soon Lee, Bongsoo Kim
A scanning transmission X-ray microscope is operational at the 10A beamline at the Pohang Light Source. The 10A beamline provides soft X-rays in the photon energy range 100-2000 eV using an elliptically polarized undulator. The practically usable photon energy range of the scanning transmission X-ray microscopy (STXM) setup is from ∼150 to ∼1600 eV. With a zone plate of 25 nm outermost zone width, the diffraction-limited space resolution, ∼30 nm, is achieved in the photon energy range up to ∼850 eV...
May 1, 2018: Journal of Synchrotron Radiation
Vi Khanh Truong, Jitraporn Vongsvivut, Nipuni Mahanamanam Geeganagamage, Mark J Tobin, Pere Luque, Vladimir Baulin, Marco Werner, Shane Maclaughlin, Russell J Crawford, Elena P Ivanova
Damselflies Calopteryx haemorrhoidalis exhibiting black wings are found in the western Mediterranean, Algeria, France, Italy, Spain and Monaco. Wing pigmentation is caused by the presence of melanin, which is involved in physiological processes including defence reactions, wound healing and sclerotization of the insect. Despite the important physiological roles of melanin, the presence and colour variation among males and females of the C. haemorrhoidalis species and the localization of the pigment within the wing membrane remain poorly understood...
May 1, 2018: Journal of Synchrotron Radiation
Jae Yeon Park, Yesul Kim, Sangsul Lee, Jun Lim
X-ray beam-position stability is indispensable in cutting-edge experiments using synchrotron radiation. Here, for the first time, a beam-position feedback system is presented that utilizes an easy-to-use X-ray beam-position monitor incorporating a diamond-fluorescence screen. The acceptable range of the monitor is above 500 µm and the feedback system maintains the beam position within 3 µm. In addition to being inexpensive, the system has two key advantages: it works without a scale factor for position calibration, and it has no dependence on X-ray energy, X-ray intensity, beam size or beam shape...
May 1, 2018: Journal of Synchrotron Radiation
Francesca Di Lillo, Giovanni Mettivier, Roberta Castriconi, Antonio Sarno, Andrew W Stevenson, Chris J Hall, Daniel Häusermann, Paolo Russo
The principle of rotational summation of the absorbed dose for breast cancer treatment with orthovoltage X-ray beams was proposed by J. Boone in 2012. Here, use of X-ray synchrotron radiation for image guided external beam rotational radiotherapy treatment of breast cancer is proposed. Tumor irradiation occurs with the patient in the prone position hosted on a rotating bed, with her breast hanging from a hole in the bed, which rotates around a vertical axis passing through the tumor site. Horizontal collimation of the X-ray beam provides for whole breast or partial breast irradiation, while vertical translation of the bed and successive rotations allow for irradiation of the full tumor volume, with dose rates which permit also hypofractionated treatments...
May 1, 2018: Journal of Synchrotron Radiation
Diana E Bedolla, Andrea Mantuano, Arissa Pickler, Carla Lemos Mota, Delson Braz, Camila Salata, Carlos Eduardo Almeida, Giovanni Birarda, Lisa Vaccari, Regina Cély Barroso, Alessandra Gianoncelli
Radiation damage is an important aspect to be considered when analysing biological samples with X-ray techniques as it can induce chemical and structural changes in the specimens. This work aims to provide new insights into the soft X-ray induced radiation damage of the complete sample, including not only the biological tissue itself but also the substrate and embedding medium, and the tissue fixation procedure. Sample preparation and handling involves an unavoidable interaction with the sample matrix and could play an important role in the radiation-damage mechanism...
May 1, 2018: Journal of Synchrotron Radiation
Viatcheslav Berejnov, Boris Rubinstein, Lis G A Melo, Adam P Hitchcock
A dose integral of time-dependent X-ray absorption under conditions of variable photon energy and changing sample mass is derived from first principles starting with the Beer-Lambert (BL) absorption model. For a given photon energy the BL dose integral D(e, t) reduces to the product of an effective time integral T(t) and a dose rate R(e). Two approximations of the time-dependent optical density, i.e. exponential A(t) = c + aexp(-bt) for first-order kinetics and hyperbolic A(t) = c + a/(b + t) for second-order kinetics, were considered for BL dose evaluation...
May 1, 2018: Journal of Synchrotron Radiation
James Archer, Enbang Li, Marco Petasecca, Andrew Stevenson, Jayde Livingstone, Andrew Dipuglia, Jeremy Davis, Anatoly Rosenfeld, Michael Lerch
Cancer is one of the leading causes of death worldwide. External beam radiation therapy is one of the most important modalities for the treatment of cancers. Synchrotron microbeam radiation therapy (MRT) is a novel pre-clinical therapy that uses highly spatially fractionated X-ray beams to target tumours, allowing doses much higher than conventional radiotherapies to be delivered. A dosimeter with a high spatial resolution is required to provide the appropriate quality assurance for MRT. This work presents a plastic scintillator fibre optic dosimeter with a one-dimensional spatial resolution of 20 µm, an improvement on the dosimeter with a resolution of 50 µm that was demonstrated in previous work...
May 1, 2018: Journal of Synchrotron Radiation
E Boulard, A King, N Guignot, J P Deslandes, Y Le Godec, J P Perrillat, A Clark, G Morard, J P Itié
In situ microtomography at high pressure and temperature has developed rapidly in the last decade, driven by the development of new high-pressure apparatus. It is now routinely possible to characterize material under high pressure with acquisition times for tomograms of the order of tens of minutes. Here, advantage was taken of the possibility to combine the use of a pink beam projected through a standard Paris-Edinburgh press in order to demonstrate the possibility to perform high-speed synchrotron X-ray tomography at high pressure and temperature allowing complete high-resolution tomograms to be acquired in about 10 s...
May 1, 2018: Journal of Synchrotron Radiation
Juan C Aguilar, Masaki Misawa, Kiyofumi Matsuda, Yoshio Suzuki, Akihisa Takeuchi, Masato Yasumoto
In this work, the application of an undecimated wavelet transformation together with digital interferometric contrast to improve the resulting reconstructions in a digital hard X-ray Gabor holographic microscope is shown. Specifically, the starlet transform is used together with digital Zernike contrast. With this contrast, the results show that only a small set of scales from the hologram are, in effect, useful, and it is possible to enhance the details of the reconstruction.
May 1, 2018: Journal of Synchrotron Radiation
Tunhe Zhou, Hongchang Wang, Thomas Connolley, Steward Scott, Nick Baker, Kawal Sawhney
The high flux of the white X-ray beams from third-generation synchrotron light sources can significantly benefit the development of high-speed X-ray imaging, but can also bring technical challenges to existing X-ray imaging systems. One prevalent problem is that the image quality deteriorates because of dust particles accumulating on the scintillator screen during exposure to intense X-ray radiation. Here, this problem has been solved by embedding the scintillator in a flowing inert-gas environment. It is also shown that the detector maintains the quality of the captured images even after days of X-ray exposure...
May 1, 2018: Journal of Synchrotron Radiation
Liya Huang, Jun Xu, Han Guo, Yujie Wang, Jun Zhao, Jianqi Sun
Osteoporosis is a bone disease with a variety of causes, leading to bone pain and fragility to fracture. Major treatment methods include nutrition therapy, exercise therapy, drug therapy and surgical treatment, among which exercise therapy, such as swimming, is the most effective. To investigate the optimal swimming therapy regime for postmenopausal women, the effects of eight weeks of different intensity swimming exercises were studied in rat models. After the swimming program, lumbar vertebrae were dissected from all the rats and scanned by synchrotron radiation computed tomography (SRCT)...
May 1, 2018: Journal of Synchrotron Radiation
Hui Jiang, Hua Wang, Jingtao Zhu, Chaofan Xue, Jiayi Zhang, Naxi Tian, Aiguo Li
The interior structure, morphology and ligand surrounding of a sputtering-deposited chromium monolayer and Cr/C and Cr/Sc multilayers are determined by various hard X-ray techniques in order to reveal the growth characteristics of Cr-based thin films. A Cr monolayer presents a three-stage growth mode with sudden changes occurring at a layer thickness of ∼2 nm and beyond 6 nm. Cr-based multilayers are proven to have denser structures due to interfacial diffusion and layer growth mode. Cr/C and Cr/Sc multilayers have different interfacial widths resulting from asymmetry, degree of crystallinity and thermal stability...
May 1, 2018: Journal of Synchrotron Radiation
M Wu, Houlin L Xin, J O Wang, X J Li, X B Yuan, H Zeng, J C Zheng, H Q Wang
Synchrotron-based L2,3 -edge absorption spectra show strong sensitivities to the local electronic structure and chemical environment. However, detailed physical information cannot be extracted easily without computational aids. Here, using the experimental Ti L2,3 -edges absorption spectrum of SrTiO3 as a fingerprint and considering full multiplet effects, calculations yield different energy parameters characterizing local ground state properties. The peak splitting and intensity ratios of the L3 and L2 set of peaks are carefully analyzed quantitatively, giving rise to a small hybridization energy around 1...
May 1, 2018: Journal of Synchrotron Radiation
Mangalika Sinha, Mohammed H Modi, Haranath Ghosh, P K Yadav, R K Gupta
The influence of the core-hole effect on optical properties of magnesium oxide (MgO) is established through experimental determination of optical constants and first-principles density functional theory studies. Optical constants (δ and β) of MgO thin film are measured in the spectral region 40-300 eV using reflectance spectroscopy techniques at the Indus-1 synchrotron radiation source. The obtained optical constants show strong core exciton features near the Mg L-edge region, causing significant mismatch with Henke's tabulated values...
May 1, 2018: Journal of Synchrotron Radiation
Young Soo Han, Hoon Young Jeong, Sung Pil Hyun, Kim F Hayes, Chul Min Chon
During X-ray absorption spectroscopy (XAS) measurements of arsenic (As), beam-induced redox transformation is often observed. In this study, the As species immobilized by poorly crystallized mackinawite (FeS) was assessed for the susceptibility to beam-induced redox reactions as a function of sample properties including the redox state of FeS and the solid-phase As speciation. The beam-induced oxidation of reduced As species was found to be mediated by the atmospheric O2 and the oxidation products of FeS [e...
May 1, 2018: Journal of Synchrotron Radiation
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