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https://www.readbyqxmd.com/read/27914179/ammonothermal-synthesis-of-novel-nitrides-case-study-on-cagasin3
#1
Jonas Häusler, Lukas Neudert, Mathias Mallmann, Robin Niklaus, Anna-Carina L Kimmel, Nicolas S A Alt, Eberhard Schlücker, Oliver Oeckler, Wolfgang Schnick
The first gallium-containing nitridosilicate CaGaSiN3 was synthesized in newly developed high-pressure autoclaves using supercritical ammonia as solvent and nitriding agent. The reaction was conducted in ammonobasic environment starting from intermetallic CaGaSi with NaN3 as mineralizer. At 770 K, intermediate compounds were obtained, which were subsequently converted to the crystalline nitride at temperatures up to 1070 K (70 - 150 MPa). The impact of other mineralizers (e. g. LiN3, KN3 and CsN3) on the product formation was investigated as well...
December 3, 2016: Chemistry: a European Journal
https://www.readbyqxmd.com/read/27914134/association-between-lumbar-bone-mineral-density-and-carotid-intima-media-thickness-in-korean-adults-a-cross-sectional-study-of-healthy-twin-study
#2
Jinyoung Shin, Joo Hyun Park, Yun Mi Song, Kayoung Lee, Joohon Sung
Bone mineral density (BMD) has been suggested to be associated with atherosclerosis. In the present study, we evaluated the association between lumbar BMD and the segments of carotid intima-media thickness (CIMT), a surrogate marker of subclinical atherosclerosis, in Korean adults, with consideration of sex and menopause status. Among 1,679 Korean adults who enrolled in a Healthy Twin Study, 723 men, 690 premenopausal women, and 266 postmenopausal women measured the CIMT at the common carotid artery intima-media thickness (CCA-IMT), carotid bifurcation intima-media thickness (BIF-IMT), internal carotid artery intima-media thickness (ICA-IMT) using B-mode ultrasound and lumbar BMD using dual-energy X-ray absorptiometry...
January 2017: Journal of Korean Medical Science
https://www.readbyqxmd.com/read/27914049/modeling-binding-affinity-of-pathological-mutations-for-computational-protein-design
#3
Miguel Romero-Durana, Chiara Pallara, Fabian Glaser, Juan Fernández-Recio
An important aspect of protein functionality is the formation of specific complexes with other proteins, which are involved in the majority of biological processes. The functional characterization of such interactions at molecular level is necessary, not only to understand biological and pathological phenomena but also to design improved, or even new interfaces, or to develop new therapeutic approaches. X-ray crystallography and NMR spectroscopy have increased the number of 3D protein complex structures deposited in the Protein Data Bank (PDB)...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/27913900/bone-mineral-density-of-extremities-is-associated-with-coronary-calcification-and-biopsy-verified-vascular-calcification-in-living-donor-renal-transplant-recipients
#4
Zhimin Chen, Jia Sun, Mathias Haarhaus, Peter Barany, Lars Wennberg, Jonaz Ripsweden, Torkel B Brismar, Bengt Lindholm, Annika Wernerson, Magnus Söderberg, Peter Stenvinkel, Abdul Rashid Qureshi
Chronic kidney disease (CKD) mineral and bone disorders (CKD-MBD) may lead to low bone mineral density (BMD) and vascular calcification (VC), but links to the latter are unclear. Here we investigated associations between BMD, coronary artery calcium (CAC) scores, and histological signs of VC in end-stage renal disease (ESRD) patients undergoing living-donor kidney transplantation (LD-Rtx). In 66 ESRD patients (median age 45 years, 68% males), BMD (by dual-energy X-ray absorptiometry, DXA), CAC score (by computed tomography, CT; n = 54), and degree of VC score (graded by histological examination of epigastric artery specimens collected at LD-Rtx; n = 55) were assessed at the time of LD-Rtx...
December 2, 2016: Journal of Bone and Mineral Metabolism
https://www.readbyqxmd.com/read/27913850/two-novel-cyclic-hexapeptides-from-the-genetically-engineered-actinosynnema-pretiosum
#5
Chunhua Lu, Fei Xie, Chuan Shan, Yuemao Shen
Two novel cyclic hexapeptides designated actinosynneptides A (1) and B (2), together with three tryptophan containing diketopiperazines, namely cyclo(L-Trp-L-Trp) (3), cyclo(L-Trp-N-MeL-Trp) (4), and cyclo(N-MeL-Trp-N-MeL-Trp) (5), were isolated from the culture of the genetically engineered strain HGF052::asm18 derived from Actinosynnema pretiosum ATCC31565. Their structures were elucidated on the basis of spectroscopic analyses and single-crystal X-ray diffractions. Compound 1 is the first example of 3-amino-6-hydroxy-2-piperidone-containing cyclic peptides, and 1 and 2 showed moderate cytotoxic activities against HeLa and PC3 cell lines...
December 2, 2016: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/27913731/disentangling-polydispersity-in-the-pcna-p15paf-complex-a-disordered-transient-and-multivalent-macromolecular-assembly
#6
Tiago N Cordeiro, Po-Chia Chen, Alfredo De Biasio, Nathalie Sibille, Francisco J Blanco, Jochen S Hub, Ramon Crehuet, Pau Bernadó
The intrinsically disordered p15(PAF) regulates DNA replication and repair when interacting with the Proliferating Cell Nuclear Antigen (PCNA) sliding clamp. As many interactions between disordered proteins and globular partners involved in signaling and regulation, the complex between p15(PAF) and trimeric PCNA is of low affinity, forming a transient complex that is difficult to characterize at a structural level due to its inherent polydispersity. We have determined the structure, conformational fluctuations, and relative population of the five species that coexist in solution by combining small-angle X-ray scattering (SAXS) with molecular modelling...
December 1, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27913383/traumatic-haemopneumothorax-and-whole-body-subcutaneous-emphysema-successful-use-of-a-small-bore-chest-drain
#7
Benjamin Hardy, Nicholas Sunderland, Mevan Perera, Kathryn Channing
A 56-year-old man presented having had two falls at home. He had a background of multiple sclerosis. After his second fall, during which he had fallen onto the toilet injuring his right chest, he was brought into the emergency department reporting pleuritic chest discomfort. Immediately evident was extensive swelling from his forehead to his thighs, which on palpation was found to be subcutaneous emphysema. A chest X-ray showed a large right-sided pneumothorax for which a chest drain was inserted. A CT revealed extensive surgical emphysema, pneumomediastinum, pneumoperitoneum and gas within the spinal canal...
December 2, 2016: BMJ Case Reports
https://www.readbyqxmd.com/read/27913358/conformational-sampling-of-a-biomolecular-rugged-energy-landscape
#8
Jakub Rydzewski, Rafal Jakubowski, Giuseppe Nicosia, Wieslaw Nowak
The protein structure refinement using conformational sampling is important in hitherto protein studies. In this paper we examined the protein structure refinement by means of potential energy minimization using immune computing as a method of sampling conformations. The method was tested on the x-ray structure and 30 decoys of the mutant of [Leu]Enkephalin, a paradigmatic example of the biomolecular multiple-minima problem. In order to score the refined conformations, we used a standard potential energy function with the OPLSAA force field...
December 1, 2016: IEEE/ACM Transactions on Computational Biology and Bioinformatics
https://www.readbyqxmd.com/read/27913326/delay-and-standard-deviation-beamforming-to-enhance-specular-reflections-in-ultrasound-imaging
#9
Raja Sekhar Bandaru, Anders Rasmus Sornes, Jeroen Hermans, Eigil Samset, Jan D'hooge
Although interventional devices, such as needles, guide wires, and catheters, are best visualized by X-ray, real-time volumetric echography could offer an attractive alternative as it avoids ionizing radiation; it provides good soft tissue contrast, and it is mobile and relatively cheap. Unfortunately, as echography is traditionally used to image soft tissue and blood flow, the appearance of interventional devices in conventional ultrasound images remains relatively poor, which is a major obstacle toward ultrasound-guided interventions...
December 2016: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/27913241/evaluation-of-highly-branched-cyclic-dextrin-in-inhalable-particles-of-combined-antibiotics-for-the-pulmonary-delivery-of-anti-tuberculosis-drugs
#10
Kazunori Kadota, Arisa Senda, Hideaki Tagishi, John Oluwasogo Ayorinde, Yuichi Tozuka
This work aims to identify a suitable formulation for the pulmonary delivery of combinations of inhalational drugs using highly branched cyclic dextrin (HBCD) macromolecules. We compared the effectiveness between powders prepared from HBCD with those prepared from five alternative excipients (lactose, maltose, sucrose, β-cyclodextrin and methyl β-cyclodextrin) in the pulmonary delivery of a single-dosage form of two anti-tuberculosis drugs (isoniazid and rifampicin). Fine particles of untreated active pharmaceutical ingredients (APIs) and combination products using excipients were prepared by spray drying...
November 29, 2016: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/27912185/sorption-of-vanadium-v-onto-natural-soil-colloids-under-various-solution-ph-and-ionic-strength-conditions
#11
Xiuhua Luo, Lin Yu, Changzhao Wang, Xianqiang Yin, Ahmed Mosa, Jialong Lv, Huimin Sun
Batch sorption kinetics and isothermal characteristics of V(V) were investigated on three natural soil colloids (manual loessial soil colloid (MSC), aeolian sandy soil colloid (ASC), and cultivated loessial soil colloid (CSC)) under various solution pH and ionic strength (IS) conditions. Colloids were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). AFM micrographs showed CSC with an aggregated shape with larger particle diameter as compared with ASC and MSC...
November 29, 2016: Chemosphere
https://www.readbyqxmd.com/read/27912167/beamstop-based-low-background-ptychography-to-image-weakly-scattering-objects
#12
Juliane Reinhardt, Robert Hoppe, Georg Hofmann, Christian D Damsgaard, Jens Patommel, Christoph Baumbach, Sina Baier, Amélie Rochet, Jan-Dierk Grunwaldt, Gerald Falkenberg, Christian G Schroer
In recent years, X-ray ptychography has been established as a valuable tool for high-resolution imaging. Nevertheless, the spatial resolution and sensitivity in coherent diffraction imaging are limited by the signal that is detected over noise and over background scattering. Especially, coherent imaging of weakly scattering specimens suffers from incoherent background that is generated by the interaction of the central beam with matter along its propagation path in particular close to and inside of the detector...
November 14, 2016: Ultramicroscopy
https://www.readbyqxmd.com/read/27912123/synthesis-of-hierarchical-porous-zinc-oxide-zno-microspheres-with-highly-efficient-adsorption-of-congo-red
#13
Chunsheng Lei, Meng Pi, Chuanjia Jiang, Bei Cheng, Jiaguo Yu
Hierarchical porous zinc oxide (ZnO) was successfully synthesized via a facile hydrothermal method followed by calcination, and characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption, and Fourier transform infrared spectroscopy analyses. The as-prepared porous ZnO exhibits microsphere morphologies with diameters of 6-8μm, which are assembled from two-dimensional nanosheets. The as-prepared hierarchical porous ZnO microspheres possessed high specific surface areas (57m(2)/g), and were evaluated for adsorption of Congo red (CR) in aqueous solution...
November 15, 2016: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/27911885/ambient-pressure-photoelectron-spectroscopy-practical-considerations-and-experimental-frontiers
#14
Lena Trotochaud, Ashley R Head, Osman Karslıoğlu, Line Kyhl, Hendrik Bluhm
Over the past several decades, ambient pressure x-ray photoelectron spectroscopy (APXPS) has emerged as a powerful technique for in situ and operando investigations of chemical reactions under relevant ambient atmospheres far from ultra-high vacuum conditions. This review focuses on exemplary cases of APXPS experiments, giving special consideration to experimental techniques, challenges, and limitations specific to distinct condensed matter interfaces. We discuss APXPS experiments on solid/vapor interfaces, including the special case of 2D films of graphene and hexagonal boron nitride on metal substrates with intercalated gas molecules, liquid/vapor interfaces, and liquid/solid interfaces, which are a relatively new class of interfaces being probed by APXPS...
December 2, 2016: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/27911879/interface-electronic-structure-at-the-topological-insulator-ferrimagnetic-insulator-junction
#15
Y Kubota, K Murata, J Miyawaki, K Ozawa, M C Onbasli, T Shirasawa, B Feng, Sh Yamamoto, R-Y Liu, S Yamamoto, S K Mahatha, P Sheverdyaeva, P Moras, C A Ross, S Suga, Y Harada, K L Wang, I Matsuda
An interface electron state at the junction between a three-dimensional topological insulator film, Bi2Se3, and a ferrimagnetic insulator film, Y3Fe5O12 (YIG), was investigated by measurements of angle-resolved photoelectron spectroscopy and x-ray absorption magnetic circular dichroism. The surface state of the Bi2Se3 film was directly observed and localized 3d spin states of the Fe(3+) in the YIG film were confirmed. The proximity effect is likely described in terms of the exchange interaction between the localized Fe 3d electrons in the YIG film and delocalized electrons of the surface and bulk states in the Bi2Se3 film...
December 2, 2016: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/27911835/two-crystal-structures-reveal-design-for-repurposing-the-c-ala-domain-of-human-alars
#16
Litao Sun, Youngzee Song, David Blocquel, Xiang-Lei Yang, Paul Schimmel
The 20 aminoacyl tRNA synthetases (aaRSs) couple each amino acid to their cognate tRNAs. During evolution, 19 aaRSs expanded by acquiring novel noncatalytic appended domains, which are absent from bacteria and many lower eukaryotes but confer extracellular and nuclear functions in higher organisms. AlaRS is the single exception, with an appended C-terminal domain (C-Ala) that is conserved from prokaryotes to humans but with a wide sequence divergence. In human cells, C-Ala is also a splice variant of AlaRS...
November 28, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911811/the-structure-of-the-catechin-binding-site-of-human-sulfotransferase-1a1
#17
Ian Cook, Ting Wang, Mark Girvin, Thomas S Leyh
We are just beginning to understand the allosteric regulation of the human cytosolic sulfotransferase (SULTs) family-13 disease-relevant enzymes that regulate the activities of hundreds, if not thousands, of signaling small molecules. SULT1A1, the predominant isoform in adult liver, harbors two noninteracting allosteric sites, each of which binds a different molecular family: the catechins (naturally occurring flavonols) and nonsteroidal antiinflammatory drugs (NSAIDs). Here, we present the structure of an SULT allosteric binding site-the catechin-binding site of SULT1A1 bound to epigallocatechin gallate (EGCG)...
November 23, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911786/geometry-induced-sequence-of-nanoscale-frank-kasper-and-quasicrystal-mesophases-in-giant-surfactants
#18
Kan Yue, Mingjun Huang, Ryan L Marson, Jinlin He, Jiahao Huang, Zhe Zhou, Jing Wang, Chang Liu, Xuesheng Yan, Kan Wu, Zaihong Guo, Hao Liu, Wei Zhang, Peihong Ni, Chrys Wesdemiotis, Wen-Bin Zhang, Sharon C Glotzer, Stephen Z D Cheng
Frank-Kasper (F-K) and quasicrystal phases were originally identified in metal alloys and only sporadically reported in soft materials. These unconventional sphere-packing schemes open up possibilities to design materials with different properties. The challenge in soft materials is how to correlate complex phases built from spheres with the tunable parameters of chemical composition and molecular architecture. Here, we report a complete sequence of various highly ordered mesophases by the self-assembly of specifically designed and synthesized giant surfactants, which are conjugates of hydrophilic polyhedral oligomeric silsesquioxane cages tethered with hydrophobic polystyrene tails...
November 28, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911781/structure-and-mechanism-of-nov1-a-resveratrol-cleaving-dioxygenase
#19
Ryan P McAndrew, Noppadon Sathitsuksanoh, Michael M Mbughuni, Richard A Heins, Jose H Pereira, Anthe George, Kenneth L Sale, Brian G Fox, Blake A Simmons, Paul D Adams
Stilbenes are diphenyl ethene compounds produced naturally in a wide variety of plant species and some bacteria. Stilbenes are also derived from lignin during kraft pulping. Stilbene cleavage oxygenases (SCOs) cleave the central double bond of stilbenes, forming two phenolic aldehydes. Here, we report the structure of an SCO. The X-ray structure of NOV1 from Novosphingobium aromaticivorans was determined in complex with its substrate resveratrol (1.89 Å), its product vanillin (1.75 Å), and without any bound ligand (1...
November 30, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911539/erratum-experimental-x-ray-ghost-imaging-phys-rev-lett-117-113902-2016
#20
Daniele Pelliccia, Alexander Rack, Mario Scheel, Valentina Cantelli, David M Paganin
This corrects the article DOI: 10.1103/PhysRevLett.117.113902.
November 18, 2016: Physical Review Letters
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