bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolving affinity between Coulombic reversibility and hysteretic phase transformations in nano-structured silicon-based lithium-ion batteries
Authors: Ogata K. , Jeon S. , Ko D.-S. , Jung I. S. , Kim J. H. , Ito K. , Kubo Y. , Takei K. , Saito S. , Cho Y.-H. , Park H. , Jang J. , Kim H.-G. , Kim J.-H. , Kim Y. S. , Choi W. , Koh M. , Uosaki K. , Doo S. G. , Hwang Y. , Han S. 
Published: January 2018

AbstractNano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the anode designs with higher silicon concentrations remain to be commercialized despite recent remarkable progress. One of the most critical issues is the fundamental understanding of the lithium–silicon Coulombic efficiency. Particularly, this is the key to resolve subtle yet accumulatively significant alterations of Coulombic efficiency by various paths of lithium–silicon processes over cycles. Here, we provide quantitative and qualitative insight into how the irreversible behaviors are altered by the processes under amorphous volume changes and hysteretic amorphous–crystalline phase transformations. Repeated latter transformations over cycles, typically featured as a degradation factor, can govern the reversibility behaviors, improving the irreversibility and eventually minimizing cumulative irreversible lithium consumption. This is clearly different from repeated amorphous volume changes with different lithiation depths. The mechanism behind the correlations is elucidated by electrochemical and structural probing.
Mössbauer spectroscopy of a monolayer of single molecule magnets
Authors: Cini Alberto , Mannini Matteo , Totti Federico , Fittipaldi Maria , Spina Gabriele , Chumakov Aleksandr , Rüffer Rudolf , Cornia Andrea , Sessoli Roberta 
Published: January 2018

AbstractThe use of single molecule magnets (SMMs) as cornerstone elements in spintronics and quantum computing applications demands that magnetic bistability is retained when molecules are interfaced with solid conducting surfaces. Here, we employ synchrotron Mössbauer spectroscopy to investigate a monolayer of a tetrairon(III) (Fe4) SMM chemically grafted on a gold substrate. At low temperature and zero magnetic field, we observe the magnetic pattern of the Fe4 molecule, indicating slow spin fluctuations compared to the Mössbauer timescale. Significant structural deformations of the magnetic core, induced by the interaction with the substrate, as predicted by ab initio molecular dynamics, are also observed. However, the effects of the modifications occurring at the individual iron sites partially compensate each other, so that slow magnetic relaxation is retained on the surface. Interestingly, these deformations escaped detection by conventional synchrotron-based techniques, like X-ray magnetic circular dichroism, thus highlighting the power of synchrotron Mössbauer spectroscopy for the investigation of hybrid interfaces.
Revealing hole trapping in zinc oxide nanoparticles by time-resolved X-ray spectroscopy
Authors: Penfold Thomas J. , Szlachetko Jakub , Santomauro Fabio G. , Britz Alexander , Gawelda Wojciech , Doumy Gilles , March Anne Marie , Southworth Stephen H. , Rittmann Jochen , Abela Rafael , Chergui Majed , Milne Christopher J. 
Published: January 2018

AbstractNanostructures of transition metal oxides, such as zinc oxide, have attracted considerable interest for solar-energy conversion and photocatalysis. Both applications are sensitive to the transport and trapping of photoexcited charge carriers. The probing of electron trapping has recently become possible using time-resolved element-sensitive methods, such as X-ray spectroscopy. However, valence-band-trapped holes have so far escaped observation. Herein we use X-ray absorption spectroscopy combined with a dispersive X-ray emission spectrometer to probe the charge carrier relaxation and trapping processes in zinc oxide nanoparticles after above band-gap photoexcitation. Our results, supported by simulations, demonstrate that within 80 ps, photoexcited holes are trapped at singly charged oxygen vacancies, which causes an outward displacement by ~15% of the four surrounding zinc atoms away from the doubly charged vacancy. This identification of the hole traps provides insight for future developments of transition metal oxide-based nanodevices.
Activin-dependent signaling in fibro/adipogenic progenitors causes fibrodysplasia ossificans progressiva
Authors: Lees-Shepard John B. , Yamamoto Masakazu , Biswas Arpita A. , Stoessel Sean J. , Nicholas Sarah-Anne E. , Cogswell Cathy A. , Devarakonda Parvathi M. , Schneider Michael J. , Cummins Samantha M. , Legendre Nicholas P. , Yamamoto Shoko , Kaartinen Vesa , Hunter Jeffrey W. , Goldhamer David J. 
Published: January 2018

AbstractFibrodysplasia ossificans progressiva (FOP) is a rare autosomal-dominant disorder characterized by progressive and profoundly disabling heterotopic ossification (HO). Here we show that fibro/adipogenic progenitors (FAPs) are a major cell-of-origin of HO in an accurate genetic mouse model of FOP (Acvr1
tnR206H
). Targeted expression of the disease-causing type I bone morphogenetic protein (BMP) receptor, ACVR1(R206H), to FAPs recapitulates the full spectrum of HO observed in FOP patients. ACVR1(R206H)-expressing FAPs, but not wild-type FAPs, activate osteogenic signaling in response to activin ligands. Conditional loss of the wild-type Acvr1 allele dramatically exacerbates FAP-directed HO, suggesting that mutant and wild-type ACVR1 receptor complexes compete for activin ligands or type II BMP receptor binding partners. Finally, systemic inhibition of activin A completely blocks HO and restores wild-type-like behavior to transplanted Acvr1
R206H/+
FAPs. Understanding the cells that drive HO may facilitate the development of cell-specific therapeutic approaches to inhibit catastrophic bone formation in FOP.
Direct effects of transcranial electric stimulation on brain circuits in rats and humans
Authors: Vöröslakos Mihály , Takeuchi Yuichi , Brinyiczki Kitti , Zombori Tamás , Oliva Azahara , Fernández-Ruiz Antonio , Kozák Gábor , Kincses Zsigmond Tamás , Iványi Béla , Buzsáki György , Berényi Antal 
Published: January 2018

AbstractTranscranial electric stimulation is a non-invasive tool that can influence brain activity; however, the parameters necessary to affect local circuits in vivo remain to be explored. Here, we report that in rodents and human cadaver brains, ~75% of scalp-applied currents are attenuated by soft tissue and skull. Using intracellular and extracellular recordings in rats, we find that at least 1 mV/mm voltage gradient is necessary to affect neuronal spiking and subthreshold currents. We designed an ‘intersectional short pulse’ stimulation method to inject sufficiently high current intensities into the brain, while keeping the charge density and sensation on the scalp surface relatively low. We verify the regional specificity of this novel method in rodents; in humans, we demonstrate how it affects the amplitude of simultaneously recorded EEG alpha waves. Our combined results establish that neuronal circuits are instantaneously affected by intensity currents that are higher than those used in conventional protocols.
Replication confers β cell immaturity
Authors: Puri Sapna , Roy Nilotpal , Russ Holger A. , Leonhardt Laura , French Esra K. , Roy Ritu , Bengtsson Henrik , Scott Donald K. , Stewart Andrew F. , Hebrok Matthias 
Published: January 2018

AbstractPancreatic β cells are highly specialized to regulate systemic glucose levels by secreting insulin. In adults, increase in β-cell mass is limited due to brakes on cell replication. In contrast, proliferation is robust in neonatal β cells that are functionally immature as defined by a lower set point for glucose-stimulated insulin secretion. Here we show that β-cell proliferation and immaturity are linked by tuning expression of physiologically relevant, non-oncogenic levels of c-Myc. Adult β cells induced to replicate adopt gene expression and metabolic profiles resembling those of immature neonatal β that proliferate readily. We directly demonstrate that priming insulin-producing cells to enter the cell cycle promotes a functionally immature phenotype. We suggest that there exists a balance between mature functionality and the ability to expand, as the phenotypic state of the β cell reverts to a less functional one in response to proliferative cues.
Sustainable manufacture of insect repellents derived from Nepeta cataria
Authors: Patience Gregory S. , Karirekinyana Ginette , Galli Federico , Patience Nicolas A. , Kubwabo Cariton , Collin Guy , Bizimana Jean Claude , Boffito Daria C. 
Published: January 2018

AbstractMalaria devastates sub-Saharan Africa; the World Health Organization (WHO) estimates that 212 million people contract malaria annually and that the plasmodium virus will kill 419 000 in 2017. The disease affects rural populations who have the least economic means to fight it. Impregnated mosquito nets have reduced the mortality rate but the Anopheles mosquitoes are changing their feeding patterns and have become more active at dusk and early morning rather than after 22h00 as an adaptation to the nets. Everyone is susceptible to the Anopheles at these times but infants and pregnant women are the most vulnerable to the disease. Plant-based mosquito repellents are as effective as synthetic repellents that protect people from bites. They are sustainable preventative measures against malaria not only because of their efficacy but because the local population can produce and distribute them, which represents a source of economic growth for rural areas. Here, we extract and test the essential oil nepetalactone from Nepeta cataria via steam distillation. Families in endemic areas of Burundi found them effective against bites but commented that the odor was pungent. An epidemiological study is required to establish its clinical efficacy.
Structure-guided design of Serratia marcescens short-chain dehydrogenase/reductase for stereoselective synthesis of (R)-phenylephrine
Authors: Liu Jai-Shin , Kuan Yi-Chia , Tsou Yu , Lin Tung-Yueh , Hsu Wen-Hwei , Yang Ming-Te , Lin Jong-Yih , Wang Wen-Ching 
Published: January 2018

AbstractBioconversion is useful to produce optically pure enantiomers in the pharmaceutical industry, thereby avoiding problems with side reactions during organic synthesis processes. A short-chain dehydrogenase/reductase from Serratia marcescens BCRC 10948 (SmSDR) can stereoselectively convert 1-(3-hydroxyphenyl)-2-(methylamino) ethanone (HPMAE) into (R)-phenylephrine [(R)-PE], which is marketed medically as a nasal decongestant agent. The whole-cell conversion process for the synthesis of (R)-PE using SmSDR was reported to have an unexpectedly low conversion rate. We reported the crystal structure of the SmSDR and designed profitable variants to improve the enzymatic activity by structure-guided approach. Several important residues in the structure were observed to form hydrophobic clusters that stabilize the mobile loops surrounding the pocket. Of these, Phe98 and Phe202 face toward each other and connect the upper curvature from the two arms (i.e., the α7 helix and loopβ4–α4). The mutant structure of the double substitutions (F98YF202Y) exhibited a hydrogen bond between the curvatures that stabilizes the flexible arms. Site-directed mutagenesis characterization revealed that the mutations (F98Y, F98YF202Y, and F98YF202L) of the flexible loops that stabilize the region exhibited a higher transformation activity toward HPMAE. Together, our results suggest a robust structure-guided approach that can be used to generate a valuable engineered variant for pharmaceutical applications.
Implementation of a Talbot-Lau interferometer in a clinical-like c-arm setup: A feasibility study
Authors: Horn Florian , Leghissa Martino , Kaeppler Sebastian , Pelzer Georg , Rieger Jens , Seifert Maria , Wandner Johannes , Weber Thomas , Michel Thilo , Riess Christian , Anton Gisela 
Published: January 2018

AbstractX-ray grating-based phase-contrast imaging has raised interest regarding a variety of potential clinical applications, whereas the method is feasible using a medical x-ray tube. Yet, the transition towards a clinical setup remains challenging due to the requirement of mechanical robustness of the interferometer and high demands applying to medical equipment in clinical use. We demonstrate the successful implementation of a Talbot-Lau interferometer in an interventional c-arm setup. The consequence of vibrations induced by the rotating anode of the tube is discussed and the prototype is shown to provide a visibility of 21.4% at a tube voltage of 60 kV despite the vibrations. Regarding clinical application, the prototype is mainly set back due to the limited size of the field of view covering an area of 17 mm × 46 mm. A c-arm offers the possibility to change the optical axis according to the requirements of the medical examination. We provide a method to correct for artifacts that result from the angulation of the c-arm. Finally, the images of a series of measurements with the c-arm in different angulated positions are shown. Thereby, it is sufficient to perform a single reference measurement in parking position that is valid for the complete series despite angulation.
High Density Lipoproteins Inhibit Oxidative Stress-Induced Prostate Cancer Cell Proliferation
Authors: Ruscica Massimiliano , Botta Margherita , Ferri Nicola , Giorgio Eleonora , Macchi Chiara , Franceschini Guido , Magni Paolo , Calabresi Laura , Gomaraschi Monica 
Published: January 2018

AbstractRecent evidence suggests that oxidative stress can play a role in the pathogenesis and the progression of prostate cancer (PCa). Reactive oxygen species (ROS) generation is higher in PCa cells compared to normal prostate epithelial cells and this increase is proportional to the aggressiveness of the phenotype. Since high density lipoproteins (HDL) are known to exert antioxidant activities, their ability to reduce ROS levels and the consequent impact on cell proliferation was tested in normal and PCa cell lines. HDL significantly reduced basal and H2O2-induced oxidative stress in normal, androgen receptor (AR)-positive and AR-null PCa cell lines. AR, scavenger receptor BI and ATP binding cassette G1 transporter were not involved. In addition, HDL completely blunted H2O2-induced increase of cell proliferation, through their capacity to prevent the H2O2-induced shift of cell cycle distribution from G0/G1 towards G2/M phase. Synthetic HDL, made of the two main components of plasma-derived HDL (apoA-I and phosphatidylcholine) and which are under clinical development as anti-atherosclerotic agents, retained the ability of HDL to inhibit ROS production in PCa cells. Collectively, HDL antioxidant activity limits cell proliferation induced by ROS in AR-positive and AR-null PCa cell lines, thus supporting a possible role of HDL against PCa progression.
Third-order transport coefficients for localised and delocalised charged-particle transport
Authors: Stokes Peter W. , Simonović Ilija , Philippa Bronson , Cocks Daniel , Dujko Saša , White Ronald D. 
Published: January 2018

AbstractWe derive third-order transport coefficients of skewness for a phase-space kinetic model that considers the processes of scattering collisions, trapping, detrapping and recombination losses. The resulting expression for the skewness tensor provides an extension to Fick’s law which is in turn applied to yield a corresponding generalised advection-diffusion-skewness equation. A physical interpretation of trap-induced skewness is presented and used to describe an observed negative skewness due to traps. A relationship between skewness, diffusion, mobility and temperature is formed by analogy with Einstein’s relation. Fractional transport is explored and its effects on the flux transport coefficients are also outlined.
Diffraction based Hanbury Brown and Twiss interferometry at a hard x-ray free-electron laser
Authors: Gorobtsov O. Yu. , Mukharamova N. , Lazarev S. , Chollet M. , Zhu D. , Feng Y. , Kurta R. P. , Meijer J.-M. , Williams G. , Sikorski M. , Song S. , Dzhigaev D. , Serkez S. , Singer A. , Petukhov A. V. , Vartanyants I. A. 
Published: January 2018

AbstractX-ray free-electron lasers (XFELs) provide extremely bright and highly spatially coherent x-ray radiation with femtosecond pulse duration. Currently, they are widely used in biology and material science. Knowledge of the XFEL statistical properties during an experiment may be vitally important for the accurate interpretation of the results. Here, for the first time, we demonstrate Hanbury Brown and Twiss (HBT) interferometry performed in diffraction mode at an XFEL source. It allowed us to determine the XFEL statistical properties directly from the Bragg peaks originating from colloidal crystals. This approach is different from the traditional one when HBT interferometry is performed in the direct beam without a sample. Our analysis has demonstrated nearly full (80%) global spatial coherence of the XFEL pulses and an average pulse duration on the order of ten femtoseconds for the monochromatized beam, which is significantly shorter than expected from the electron bunch measurements.
3D auxetic single material periodic structure with ultra-wide tunable bandgap
Authors: D’Alessandro Luca , Zega Valentina , Ardito Raffaele , Corigliano Alberto 
Published: January 2018

AbstractThe design and the combination of innovative metamaterials are attracting increasing interest in the scientific community because of their unique properties that go beyond the ones of natural materials. In particular, auxetic materials and phononic crystals are widely studied for their negative Poisson’s ratio and their bandgap opening properties, respectively. In this work, auxeticity and phononic crystals bandgap properties are properly combined to obtain a single phase periodic structure with a tridimensional wide tunable bandgap. When an external tensile load is applied to the structure, the auxetic unit cells change their configurations by exploiting the negative Poisson’s ratio and this results in the tuning, either hardening or softening, of the frequencies of the modes limiting the 3D bandgap. Moreover, the expansion of the unit cell in all the directions, due to the auxeticity property, guarantees a fully 3D bandgap tunability of the proposed structure. Numerical simulations and analytical models are proposed to prove the claimed properties. The first experimental evidence of the tunability of a wide 3D bandgap is then shown thanks to the fabrication of a prototype by means of additive manufacturing.
Haloperidol–induced catalepsy is ameliorated by deep brain stimulation of the inferior colliculus
Authors: Engelhardt K.-Alexander , Marchetta Philine , Schwarting Rainer K. W. , Melo-Thomas Liana 
Published: January 2018

AbstractDeep brain stimulation (DBS) has evolved as a promising alternative treatment for Parkinson’s disease (PD), but the underlying mechanisms remain poorly understood. Moreover, conventional DBS protocols targeted at basal ganglia sites can turn out completely ineffective for some PD patients, warranting the search for alternative targets. The inferior colliculus (IC) is a midbrain auditory relay station involved in sensorimotor processes. High-frequency 2500 Hz electrical stimulation of the IC elicits escape behaviour and interferes with haloperidol-induced catalepsy in rats, a state reminiscent of Parkinsonian akinesia, but clinical implication is limited since the protocol is aversive. However, typical DBS stimulation frequencies range between 20–180 Hz. We therefore tested the effects of a low-frequency 30 Hz-DBS protocol on haloperidol-induced catalepsy and aversive behaviour in rats. We show that low-frequency 30 Hz-DBS targeted at the IC strongly ameliorates haloperidol-induced catalepsy without any evidence of stimulation-induced escape behaviour. Furthermore, 30 Hz-DBS of the IC produced no place avoidance in a place conditioning paradigm and induced no anxiety-related behaviour on the elevated plus maze, indicating that the protocol has no aversive or anxiogenic side effects. Our findings provide first evidence that the IC can serve as an alternative, non-conventional DBS target.
Ants improve the reproduction of inferior morphs to maintain a polymorphism in symbiont aphids
Authors: Watanabe Saori , Yoshimura Jin , Hasegawa Eisuke 
Published: January 2018

AbstractIdentifying stable polymorphisms is essential for understanding biodiversity. Distinctive polymorphisms are rare in nature because a superior morph should dominate a population. In addition to the three known mechanisms for polymorphism persistence, we recently reported a fourth mechanism: protection of the polymorphism by symbionts. Attending ants preferentially protect polymorphic aphid colonies consisting of green and red morphs. Here, we show that attending ants manipulate the reproductive rate of their preferred green morphs to equal that of the red morphs, leading to the persistence of the polymorphism within the colonies. We could not, however, explain how the ants maintained the polymorphism in aphid colonies regardless of inter-morph competition. Manipulation by symbionts may be important for the maintenance of polymorphisms and the resulting biodiversity in certain symbiotic systems.
Comparative phosphoproteomic analysis reveals signaling networks regulating monopolar and bipolar cytokinesis
Authors: Karayel Özge , Şanal Erdem , Giese Sven H. , Üretmen Kagıalı Zeynep Cansu , Polat Ayşe Nur , Hu Chi-Kuo , Renard Bernhard Y. , Tuncbag Nurcan , Özlü Nurhan 
Published: January 2018

AbstractThe successful completion of cytokinesis requires the coordinated activities of diverse cellular components including membranes, cytoskeletal elements and chromosomes that together form partly redundant pathways, depending on the cell type. The biochemical analysis of this process is challenging due to its dynamic and rapid nature. Here, we systematically compared monopolar and bipolar cytokinesis and demonstrated that monopolar cytokinesis is a good surrogate for cytokinesis and it is a well-suited system for global biochemical analysis in mammalian cells. Based on this, we established a phosphoproteomic signature of cytokinesis. More than 10,000 phosphorylation sites were systematically monitored; around 800 of those were up-regulated during cytokinesis. Reconstructing the kinase-substrate interaction network revealed 31 potentially active kinases during cytokinesis. The kinase-substrate network connects proteins between cytoskeleton, membrane and cell cycle machinery. We also found consensus motifs of phosphorylation sites that can serve as biochemical markers specific to cytokinesis. Beyond the kinase-substrate network, our reconstructed signaling network suggests that combination of sumoylation and phosphorylation may regulate monopolar cytokinesis specific signaling pathways. Our analysis provides a systematic approach to the comparison of different cytokinesis types to reveal alternative ways and a global overview, in which conserved genes work together and organize chromatin and cytoplasm during cytokinesis.