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synchrotron radiation

Yuguang Ying, Huihua Zhang, Peiqiang Yu
The cutting-edge synchrotron radiation based and globar-sourced vibrational infrared microspectroscopy have recently been developed. These novel techniques are able to reveal structure features at cellular and molecular levels with the tested tissues being intact. However, to date, the advanced techniques are unfamiliar or unknown to food and feed scientists and have not been used to study the molecular structure changes in cool-climate cereal grain seeds and other types of bio-oil and bioenergy seeds. This article aims to provide some recent research in cool-climate cereal grains and other types of seeds on molecular structures and metabolic characteristics of carbohydrate and protein, and implication of microstructure modification through heat-related processing and trait alteration to bio-functions, molecular thermal stability and mobility, and nutrition with advanced molecular techniques- synchrotron radiation based and globar-sourced vibrational infrared microspectroscopy in the areas of (1) Inherent microstructure of cereal grain seeds; (2) The nutritional values of cereal grains; (3) Impact and modification of heat-related processing to cereal grain; (4) Conventional nutrition evaluation methodology; (5) Synchrotron radiation-based and globar-sourced vibrational (micro)-spectroscopy for molecular structure study and molecular thermal stability and mobility, and (6) Recent molecular spectroscopic technique applications in research on raw, traits altered and processed cool-climate cereal grains and other types of seeds...
February 16, 2018: Critical Reviews in Food Science and Nutrition
Claus-Peter Richter, Hunter Young, Sonja V Richter, Virginia Smith-Bronstein, Stuart R Stock, Xianghui Xiao, Carmen Soriano, Donna S Whitlon
Exposure to noise and ototoxic drugs are responsible for much of the debilitating hearing loss experienced by about 350 million people worldwide. Beyond hearing aids and cochlear implants, there have been no other FDA approved drug interventions established in the clinic that would either protect or reverse the effects of hearing loss. Using Auditory Brainstem Responses (ABR) in a guinea pig model, we demonstrate that fluvastatin, an inhibitor of HMG-CoA reductase, the rate-limiting enzyme of the mevalonate pathway, protects against loss of cochlear function initiated by high intensity noise...
February 14, 2018: Scientific Reports
Christian Fedon, Luigi Rigon, Fulvia Arfelli, Diego Dreossi, Elisa Quai, Maura Tonutti, Giuliana Tromba, Maria Assunta Cova, Renata Longo
Two dosimetric quantities [mean glandular dose (MGD) and entrance surface air kerma (ESAK)] and the diagnostic performance of phase-contrast mammography with synchrotron radiation (MSR) are compared to conventional digital mammography (DM). Seventy-one patients (age range, 41 to 82 years) underwent MSR after a DM examination if questionable or suspicious breast abnormalities were not clarified by ultrasonography. The MGD and the ESAK delivered in both examinations were evaluated and compared. Two on-site radiologists rated the images in consensus according to the Breast Imaging Reporting and Data System assessment categories, which were then correlated with the final diagnoses by means of statistical generalized linear models (GLMs)...
January 2018: Journal of Medical Imaging
Xiaogang Yang, Vincent De Andrade, William Scullin, Eva L Dyer, Narayanan Kasthuri, Francesco De Carlo, Doğa Gürsoy
Synchrotron-based X-ray tomography offers the potential for rapid large-scale reconstructions of the interiors of materials and biological tissue at fine resolution. However, for radiation sensitive samples, there remain fundamental trade-offs between damaging samples during longer acquisition times and reducing signals with shorter acquisition times. We present a deep convolutional neural network (CNN) method that increases the acquired X-ray tomographic signal by at least a factor of 10 during low-dose fast acquisition by improving the quality of recorded projections...
February 7, 2018: Scientific Reports
Ken Kojio, Chigusa Nagano, Aya Fujimoto, Shuhei Nozaki, Kazutoshi Yokomachi, Kazutaka Kamitani, Hirohmi Watanabe, Atsushi Takahara
It is desirable to establish a method for evaluating mechanical properties, such as modulus and strength, of micrometer and sub-micrometer thick polymer films. Bulge tests, where bulge deformation is imposed on films by the pressure of an inert gas, are suitable for satisfying this demand. However, very few studies on polymer films exist in the literature. In this study, bulge testing equipment for in situ synchrotron radiation wide-angle X-ray diffraction (WAXD) measurements is designed and used to study the relationship between the molecular aggregation structure and the mechanical properties of a crystalline nylon 12 (Ny12) film during bulge testing...
February 7, 2018: Soft Matter
Liu Zhang, Li Wu, Caifen Wang, Guoqing Zhang, Lin Yu, Hai Yan Li, Abi Maharjan, Yan Tang, Dunwei He, Peter York, Huimin Sun, Xianzhen Yin, Jiwen Zhang, Lixin Sun
One unusual and challenging scientific field that has received only cursory attention to date is the three-dimensional (3D) microstructure and spatial distribution of drug(s) and formulation materials in solid dosage forms. This study aims to pro-vide deeper insight to the relationships between the microstructure of multiple-unit pellet system (MUPS) tablets and the spa-tial distribution of the active pharmaceutical ingredient (API) and excipients to facilitate the design of quantitative models for drug delivery systems...
February 7, 2018: Analytical Chemistry
C Fedon, M Caballo, R Longo, A Trianni, I Sechopoulos
PURPOSE: To investigate the performance, such as energy dependence and sensitivity, of thermoluminescent dosimeters (TLD), metal oxide semiconductor field-effect transistor dosimeters (MOSFET), and GafChromic™ films, and to validate the estimates of local dose deposition of a Monte Carlo (MC) simulation for breast dosimetry applications. METHODS: Experimental measurements were performed using a monoenergetic beam at the ELETTRA synchrotron radiation light source (Trieste, Italy)...
February 6, 2018: Medical Physics
Takayasu Kawasaki, Toyonari Yaji, Toshiaki Ohta, Koichi Tsukiyama, Kazuhiro Nakamura
Structure of amyloid β (Aβ) fibrils is rigidly stacked by β-sheet conformation, and the fibril state of Aβ is profoundly related to pathogenesis of Alzheimer's disease (AD). Although mid-infrared light has been used for various biological researches, it has not yet been known whether the infrared light changes the fibril structure of Aβ. In this study, we tested the effect of irradiation of intense mid-infrared light from a free-electron laser (FEL) targeting the amide bond on the reduction of β-sheet content in Aβ fibrils...
February 5, 2018: Cellular and Molecular Neurobiology
E Mitri, L Barbieri, L Vaccari, E Luchinat
The ultimate goal of modern structural biology is to probe protein structures and dynamics in their physiological microenvironment. In-cell NMR spectroscopy is an ideal technique for achieving this goal, being able to investigate proteins at atomic-resolution in living cells. The reliability of the results provided by in-cell NMR relies on the selectivity of the labelling methodology coupled with the filtering capabilities offered by heteronuclear NMR experiments. However, solution NMR is not well-suited either for measuring to what extent the non-specific labelling occurs, or to evaluate how it is affected by cell-to-cell variability and, eventually, whether the labelling procedure affects the cellular macromolecular content in general...
February 6, 2018: Analyst
Céline Pisapia, Frédéric Jamme, Ludovic Duponchel, Bénédicte Ménez
Finding traces of life or organic components of prebiotic interest in the rock record is an appealing goal for numerous fields in Earth and space sciences. However, this is often hampered by the scarceness and highly heterogeneous distribution of organic compounds within rocks. We assess here an innovative analytical strategy combining Synchrotron radiation-based Fourier-Transform Infrared microspectroscopy (S-FTIR) and multivariate analysis techniques to track and characterize organic compounds at the pore level in complex oceanic rocks...
February 5, 2018: Scientific Reports
Max Rose, Tobias Senkbeil, Andreas R von Gundlach, Susan Stuhr, Christoph Rumancev, Dmitry Dzhigaev, Ilya Besedin, Petr Skopintsev, Lars Loetgering, Jens Viefhaus, Axel Rosenhahn, Ivan A Vartanyants
Coherent X-ray ptychography is a tool for highly dose efficient lensless nano-imaging of biological samples. We have used partially coherent soft X-ray synchrotron radiation to obtain a quantitative image of a laterally extended, dried, and unstained fibroblast cell by ptychography. We used data with and without a beam stop that allowed us to measure coherent diffraction with a high-dynamic range of 1.7·106. As a quantitative result, we obtained the refractive index values for two regions of the cell with respect to a reference area...
January 22, 2018: Optics Express
Rohanah Hussain, Charlotte S Hughes, Tamás Jávorfi, Giuliano Siligardi, Paul Williams, Boyan B Bonev
Thermal unfolding of proteins is used extensively in screening of drug candidates because molecular interactions with ligands and substrates affect strongly protein stability, transition temperature and cooperativity. We use synchrotron radiation circular dichroism to monitor the thermal evolution of secondary structure in proteins as they approach the melting point and the impact of substrate on their thermal behaviour. Using Landau free energy expansion, we quantify transition strength and proximity to a critical point through the relative separation τ+ between the transition temperature Tm and the spinodal T+, obtained from the equation of state...
February 5, 2018: Journal of Physical Chemistry. B
Takaumi Morita, Marko Damjanović, Keiichi Katoh, Yasutaka Kitagawa, Nobuhiro Yasuda, Yanhua Lan, Wolfgang Wernsdorfer, Brian K Breedlove, Markus Enders, Masahiro Yamashita
Herein we report the synthesis and characterization of a dinuclear TbIII single-molecule magnet (SMM) with two [TbPc2]0 units connected via a fused-phthalocyaninato ligand. The stable and robust complex [(obPc)Tb(Fused-Pc)Tb(obPc)] (1) was characterized by using synchrotron radiation measurements and other spectroscopic techniques (ESI-MS, FT-IR, UV). The magnetic couplings between the TbIII ions and the two π radicals present in 1 were explored by means of density functional theory (DFT). Direct- and alternating current magnetic susceptibility measurements were conducted on magnetically diluted and non-diluted samples of 1, indicating this compound to be an SMM with improved properties compared to those of the well-known [TbPc2]-/0/+ and the axially symmetric dinuclear TbIII phthalocyaninato triple-decker complex (Tb2(obPc)3)...
February 5, 2018: Journal of the American Chemical Society
Stevce Stefanoski, Gregory J Finkelstein, Matthew D Ward, Tao Zeng, Kaya Wei, Emma S Bullock, Christine M Beavers, Hanyu Liu, George S Nolas, Timothy A Strobel
Single crystals of a complex Zintl compound with the composition Na4Ge13 were synthesized for the first time using a high-pressure/high-temperature approach. Single-crystal diffraction of synchrotron radiation revealed a hexagonal crystal structure with P6/m space group symmetry that is composed of a three-dimensional sp3 Ge framework punctuated by small and large channels along the crystallographic c axis. Na atoms are inside hexagonal prism-based Ge cages along the small channels, while the larger channels are occupied by layers of disordered sixfold Na rings, which are in turn filled by disordered [Ge4]4- tetrahedra...
February 5, 2018: Inorganic Chemistry
Samatha Bevara, S Nagabhusan Achary, Nandini Garg, Abhishek Chitnis, P U Sastry, A B Shinde, P Siva Ram Krishna, Avesh Kumar Tyagi
The structural stability and phase transition behavior of tetragonal (I4/m) hollandite type K2Fe2Ti6O16 have been investigated by in situ high pressure X-ray diffraction using synchrotron radiation and a diamond anvil cell as well as by variable temperature powder neutron and X-ray diffraction. The tetragonal phase is found to be stable in a wider range of temperatures, while it reversibly transforms to a monoclinic (I2/m) structure at a moderate pressure, viz. 3.6 GPa. The pressure induced phase transition occurs with only a marginal change in structural arrangements...
February 3, 2018: Inorganic Chemistry
Chuanqiang Wu, Hui Xie, Dongdong Li, Daobin Liu, Shiqing Ding, Shi Tao, Heng Chen, Qin Liu, Shuangming Chen, Wangsheng Chu, Bo Zhang, Li Song
Atomic intercalation of different agents into two-dimensional layered materials can engineer the intrinsic structure at the atomic scale and thus tune the physical and chemical properties for specific applications. Here we successfully introduce tin (Sn) atoms into the interlayer of α-MoO3 nanobelts forming a new MoO3-Sn intercalation with ultra-stable structure. Combining with theoretical calculations, our synchrotron radiation-based characterizations and electron microscope observations clearly reveal that the intercalated Sn atoms could bond with five O atoms, forming a pentahedral structure...
February 1, 2018: Journal of Physical Chemistry Letters
James Tolchard, Samuel J Walpole, Andrew J Miles, Robin Maytum, Lawrence A Eaglen, Ted Hackstadt, B A Wallace, Tharin M A Blumenschein
Tarp (translocated actin recruiting phosphoprotein) is an effector protein common to all chlamydial species that functions to remodel the host-actin cytoskeleton during the initial stage of infection. In C. trachomatis, direct binding to actin monomers has been broadly mapped to a 100-residue region (726-825) which is predicted to be predominantly disordered, with the exception of a ~10-residue α-helical patch homologous to other WH2 actin-binding motifs. Biophysical investigations demonstrate that a Tarp726-825 construct behaves as a typical intrinsically disordered protein; within it, NMR relaxation measurements and chemical shift analysis identify the ten residue WH2-homologous region to exhibit partial α-helix formation...
January 31, 2018: Scientific Reports
Richard Smith, Jiaxi Wang, Colin Seymour, Cristian Fernandez-Palomo, Jennifer Fazzari, Elisabeth Schültke, Elke Bräuer-Krisch, Jean Laissue, Christian Schroll, Carmel Mothersill
To evaluate microbeam radiation therapy (MRT), for brain tumor treatment, the bystander effect in nonirradiated companion animals was investigated. Adult rats were irradiated with 35 or 350 Gy at the European Synchrotron Research Facility using homogenous irradiation (HR) or MRT to the right brain hemisphere. The irradiated rats were housed with nonirradiated rats. After 48 hours, all rats were euthanized and the frontal lobe proteome was analyzed using 2-dimensional electrophoresis and mass spectrometry. Proteome changes were determined by analysis of variance (P < ...
January 2018: Dose-response: a Publication of International Hormesis Society
Pablo Hernandez-Cerdan, Bradley William Mansel, Andrew Leis, Leif Lundin, Martin A K Williams
Polysaccharide gels assembled from the anionic biopolymers pectin and carrageenan have been studied using transmission electron microscopy (TEM). Gels were formed in several different ways: for pectin, hydrogen bonding was used to form junction-zones between strands, while for carrageenan systems several different ion types were used to form ionotropic networks. Using this approach, several distinct network architectures were realized. In addition to preparing gelled samples for electron microscopy, a set of samples was taken without performing the additional treatment necessitated by the TEM measurements, and these were studied directly by small-angle x-ray scattering (SAXS)...
January 30, 2018: Biomacromolecules
Xun Wang, Ting He, Shuangming Chen, Bing Ni, Yue Gong, Zhao Wu, Li Song, Lin Gu, Wenping Hu
Single-atom immobilized on metal-organic frameworks (MOFs) with unique nanostructures have drawn tremendous attention in the application of catalysis but remain a great challenge. In this work, various single noble metal atoms can be successfully anchored on the well-defined anchoring sites of the zirconium-porphyrinic MOF hollow nanotubes, which are probed by aberration-corrected scanning transmission electron microscopy and synchrotron-radiation-based X-ray absorption fine structure spectroscopy. Owing to the hollow structure and excellent photoelectrochemical performance, the HNTM-Ir/Pt exhibits outstanding catalytic activity in the visible-light photocatalytic H2 evolution via water splitting...
January 30, 2018: Angewandte Chemie
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