bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protection of the biconcave profile of human erythrocytes against osmotic damage by ultraviolet-A irradiation through membrane-cytoskeleton enhancement
Authors: Li Cunbo , Li Zheming , Xun Shuang , Jiang Pengchong , Yan Rui , Chen Mincai , Hu Fen , Rupp Romano A , Zhang Xinzheng , Pan Leiting , Xu Jingjun 
Published: July 2017

AbstractTo perform various physiological functions, erythrocytes possess a unique biconcave shape provided by a special architecture of the membrane-skeleton system. In the present work, we use a simple irradiation method to treat human erythrocytes with 365 nm ultraviolet-A (UVA) light at the single-cell level in vitro. Depending on the irradiation dose, UVA show protection of the biconcave profile against the detrimental action of distilled water. This protective effect can also be confirmed for saponin that damages the membrane-skeleton by vesiculation and pore formation. Interestingly, at two irradiation doses of UVA pretreatment, erythrocytes still seem to exhibit cell viability as tested by trypan blue assay even if distilled water or saponin is added. The oxidants hydrogen peroxide and cumene hydroperoxide partly simulate the protective effects. Taken together, these results demonstrate that 365 nm UVA irradiation can protect the biconcave profile of human erythrocytes through membrane-skeleton enhancement associated with a production of oxidants.
DS16570511 is a small-molecule inhibitor of the mitochondrial calcium uniporter
Authors: Kon Naohiro , Murakoshi Michiko , Isobe Aya , Kagechika Katsuji , Miyoshi Naoki , Nagayama Takahiro 
Published: July 2017

AbstractIn cardiac myocytes, regulation of mitochondrial Ca2+ is important for cellular signaling and cardiac contraction. Ca2+ entry into the mitochondria is mediated by a highly selective Ca2+ channel called the mitochondrial calcium uniporter, which consists of a pore-forming subunit MCU and regulatory subunits such as MICU1. Although pharmacological regulation of the mitochondrial Ca2+ influx is a promising approach to controlling the cellular functions, a cell-permeable and specific inhibitor of the mitochondrial calcium uniporter has not yet been developed. Here, we identify a novel cell-permeable inhibitor of the uniporter by a high-throughput screening of 120 000 small-molecule compounds. In our study, DS16570511 dose-dependently inhibited serum-induced mitochondrial Ca2+ influx in HEK293A cells with an IC50 of 7 μM. DS16570511 inhibited Ca2+ uptake of isolated mitochondria from human cells, rat heart and pig heart. Overexpression of hMCU or hMICU1 in HEK293A cells increased mitochondrial Ca2+ influx, and the increases were completely suppressed by the pretreatment with DS16570511. DS16570511 also blocks mitochondrial Ca2+ overload in a Langendorff perfused beating rat heart. Interestingly, DS16570511 increased cardiac contractility without affecting heart rate in the perfused heart. These results show that DS16570511 is a novel cell-permeable inhibitor of the mitochondrial calcium uniporter and applicable for control of the cardiac functions.
Rapid synthesis of transition metal dichalcogenide–carbon aerogel composites for supercapacitor electrodes
Authors: Crane Matthew J. , Lim Matthew B. , Zhou Xuezhe , Pauzauskie Peter J. 
Published: July 2017

AbstractTransition metal dichalcogenide (TMD) materials have recently demonstrated exceptional supercapacitor properties after conversion to a metallic phase, which increases the conductivity of the network. However, freestanding, exfoliated transition metal dichalcogenide films exhibit surface areas far below their theoretical maximum (1.2 %), can fail during electrochemical operation due to poor mechanical properties, and often require pyrophoric chemicals to process. On the other hand, pyrolyzed carbon aerogels exhibit extraordinary specific surface areas for double layer capacitance, high conductivity, and a strong mechanical network of covalent chemical bonds. In this paper, we demonstrate the scalable, rapid nanomanufacturing of TMD (MoS2and WS2) and carbon aerogel composites, favoring liquid-phase exfoliation to avoid pyrophoric chemicals. The aerogel matrix support enhances conductivity of the composite and the synthesis can complete in 30 min. We find that the addition of transition metal dichalcogenides does not impact the structure of the aerogel, which maintains a high specific surface area up to 620 m2 g−1with peak pore radii of 10 nm. While supercapacitor tests of the aerogels yield capacitances around 80 F g−1at the lowest applied currents, the aerogels loaded with TMD’s exhibit volumetric capacitances up to 127% greater than the unloaded aerogels. In addition, the WS2aerogels show excellent cycling stability with no capacitance loss over 2000 cycles, as well as markedly better rate capability and lower charge transfer resistance compared to their MoS2-loaded counterparts. We hypothesize that these differences in performance stem from differences in contact resistance and in the favorability of ion adsorption on the chalcogenides.
High-order harmonic generation from the dressed autoionizing states
Authors: Fareed M. A. , Strelkov V. V. , Thiré N. , Mondal S. , Schmidt B. E. , Légaré F. , Ozaki T. 
Published: July 2017

AbstractIn high-order harmonic generation, resonant harmonics (RH) are sources of intense, coherent extreme-ultraviolet radiation. However, intensity enhancement of RH only occurs for a single harmonic order, making it challenging to generate short attosecond pulses. Moreover, the mechanism involved behind such RH was circumstantial, because of the lack of direct experimental proofs. Here, we demonstrate the exact quantum paths that electron follows for RH generation using tin, showing that it involves not only the autoionizing state, but also a harmonic generation from dressed-AIS that appears as two coherent satellite harmonics at frequencies ±2Ω from the RH (Ω represents laser frequency). Our observations of harmonic emission from dressed states open the possibilities of generating intense and broadband attosecond pulses, thus contributing to future applications in attosecond science, as well as the perspective of studying the femtosecond and attosecond dynamics of autoionizing states.
Cryo-EM structures of the ATP-bound Vps4E233Q hexamer and its complex with Vta1 at near-atomic resolution
Authors: Sun Shan , Li Lin , Yang Fan , Wang Xiaojing , Fan Fenghui , Yang Mengyi , Chen Chunlai , Li Xueming , Wang Hong-Wei , Sui Sen-Fang 
Published: July 2017

AbstractThe cellular ESCRT-III (endosomal sorting complex required for transport-III) and Vps4 (vacuolar protein sorting 4) comprise a common machinery that mediates a variety of membrane remodelling events. Vps4 is essential for the machinery function by using the energy from ATP hydrolysis to disassemble the ESCRT-III polymer into individual proteins. Here, we report the structures of the ATP-bound Vps4E233Q hexamer and its complex with the cofactor Vta1 (vps twenty associated 1) at resolutions of 3.9 and 4.2 Å, respectively, determined by electron cryo-microscopy. Six Vps4E233Q subunits in both assemblies exhibit a spiral-shaped ring-like arrangement. Locating at the periphery of the hexameric ring, Vta1 dimer bridges two adjacent Vps4 subunits by two different interaction modes to promote the formation of the active Vps4 hexamer during ESCRT-III filament disassembly. The structural findings, together with the structure-guided biochemical and single-molecule analyses, provide important insights into the process of the ESCRT-III polymer disassembly by Vps4.
Spatial cycles mediated by UNC119 solubilisation maintain Src family kinases plasma membrane localisation
Authors: Konitsiotis Antonios D. , Roßmannek Lisaweta , Stanoev Angel , Schmick Malte , Bastiaens Philippe I. H. 
Published: July 2017

AbstractThe peripheral membrane proto-oncogene Src family protein tyrosine kinases relay growth factor signals to the cytoplasm of mammalian cells. We unravel the spatial cycles of solubilisation, trapping on perinuclear membrane compartments and vesicular transport that counter entropic equilibration to endomembranes for maintaining the enrichment and activity of Src family protein tyrosine kinases at the plasma membrane. The solubilising factor UNC119 sequesters myristoylated Src family protein tyrosine kinases from the cytoplasm, enhancing their diffusion to effectively release Src family protein tyrosine kinases on the recycling endosome by localised Arl2/3 activity. Src is then trapped on the recycling endosome via electrostatic interactions, whereas Fyn is quickly released to be kinetically trapped on the Golgi by palmitoyl acyl-transferase activity. Vesicular trafficking from these compartments restores enrichment of the Src family protein tyrosine kinases to the plasma membrane. Interference with these spatial cycles by UNC119 knockdown disrupts Src family protein tyrosine kinase localisation and signalling activity, indicating that UNC119 could be a drug target to affect oncogenic Src family protein tyrosine kinase signalling.
An optogenetic toolbox for unbiased discovery of functionally connected cells in neural circuits
Authors: Förster Dominique , Dal Maschio Marco , Laurell Eva , Baier Herwig 
Published: July 2017

AbstractOptical imaging approaches have revolutionized our ability to monitor neural network dynamics, but by themselves are unable to link a neuron’s activity to its functional connectivity. We present a versatile genetic toolbox, termed ‘Optobow’, for all-optical discovery of excitatory connections in vivo. By combining the Gal4-UAS system with Cre/lox recombination, we target the optogenetic actuator ChrimsonR and the sensor GCaMP6 to stochastically labeled, nonoverlapping and sparse subsets of neurons. Photostimulation of single cells using two-photon computer-generated holography evokes calcium responses in downstream neurons. Morphological reconstruction of neurite arbors, response latencies and localization of presynaptic markers suggest that some neuron pairs recorded here are directly connected, while others are two or more synapses apart from each other. With this toolbox, we discover wiring principles between specific cell types in the larval zebrafish tectum. Optobow should be useful for identification and manipulation of networks of interconnected neurons, even in dense neural tissues.
Why we need to quantise everything, including gravity
Authors: Marletto C. , Vedral V. 
Published: July 2017

AbstractThere is a long-standing debate about whether gravity should be quantised. A powerful line of argument in favour of quantum gravity considers models of hybrid systems consisting of coupled quantum–classical sectors. The conclusion is that such models are inconsistent: either the quantum sector’s defining properties necessarily spread to the classical sector, or they are violated. These arguments have a long history, starting with the debates about the quantum nature of the electromagnetic fields in the early days of quantum theory. Yet, they have limited scope because they rely on particular dynamical models obeying restrictive conditions, such as unitarity. In this paper we propose a radically different, more general argument, relying on less restrictive assumptions. The key feature is an information-theoretic characterisation of both sectors, including their interaction, via constraints on copying operations. These operations are necessary for the existence of observables in any physical theory, because they constitute the most general representation of measurement interactions. Remarkably, our argument is formulated without resorting to particular dynamical models, thus being applicable to any hybrid system, even those ruled by “post-quantum” theories. Its conclusion is also compatible with partially quantum systems, such as those that exhibit features like complementarity, but may lack others, such as entanglement. As an example, we consider a hybrid system of qubits and rebits. Surprisingly, despite the rebit’s lack of complex amplitudes, the signature quantum protocols such as teleportation are still possible.
Study of microstructure and fracture properties of blunt notched and sharp cracked high density polyethylene specimens
Authors: Pan Huanyu , Devasahayam Sheila , Bandyopadhyay Sri 
Published: July 2017

AbstractThis paper examines the effect of a broad range of crosshead speed (0.05 to 100 mm/min) and a small range of temperature (25 °C and 45 °C) on the failure behaviour of high density polyethylene (HDPE) specimens containing a) standard size blunt notch and b) standard size blunt notch plus small sharp crack – all tested in air. It was observed that the yield stress properties showed linear increase with the natural logarithm of strain rate. The stress intensity factors under blunt notch and sharp crack conditions also increased linearly with natural logarithm of the crosshead speed. The results indicate that in the practical temperature range of 25 °C and 45 °C under normal atmosphere and increasing strain rates, HDPE specimens with both blunt notches and sharp cracks possess superior fracture properties. SEM microstructure studies of fracture surfaces showed craze initiation mechanisms at lower strain rate, whilst at higher strain rates there is evidence of dimple patterns absorbing the strain energy and creating plastic deformation. The stress intensity factor and the yield strength were higher at 25 °C compared to those at 45 °C
Electronic structure of SrSn2As2 near the topological critical point
Authors: Rong L.-Y. , Ma J.-Z. , Nie S.-M. , Lin Z.-P. , Li Z.-L. , Fu B.-B. , Kong L.-Y. , Zhang X.-Z. , Huang Y.-B. , Weng H.-M. , Qian T. , Ding H. , Tai R.-Z. 
Published: July 2017

AbstractTopological materials with exotic quantum properties are promising candidates for quantum spin electronics. Different classes of topological materials, including Weyl semimetal, topological superconductor, topological insulator and Axion insulator, etc., can be connected to each other via quantum phase transition. For example, it is believed that a trivial band insulator can be twisted into topological phase by increasing spin-orbital coupling or changing the parameters of crystal lattice. With the results of LDA calculation and measurement by angle-resolved photoemission spectroscopy (ARPES), we demonstrate in this work that the electronic structure of SrSn2As2 single crystal has the texture of band inversion near the critical point. The results indicate the possibility of realizing topological quantum phase transition in SrSn2As2 single crystal and obtaining different exotic quantum states.
Unconventional band inversion and intrinsic quantum spin Hall effect in functionalized group-V binary films
Authors: Li Sheng-shi , Ji Wei-xiao , Li Ping , Hu Shu-jun , Zhou Tie , Zhang Chang-wen , Yan Shi-shen 
Published: July 2017

AbstractAdequately understanding band inversion mechanism, one of the significant representations of topological phase, has substantial implications for design and regulation of topological insulators (TIs). Here, by identifying an unconventional band inversion, we propose an intrinsic quantum spin Hall (QSH) effect in iodinated group-V binary (ABI2) monolayers with a bulk gap as large as 0.409 eV, guaranteeing its viable application at room temperature. The nontrivial topological characters, which can be established by explicit demonstration of Z2 invariant and gapless helical edge states, are derived from the band inversion of antibonding states of px,y orbitals at the K point. Furthermore, the topological properties are tunable under strain engineering and external electric field, which supplies a route to manipulate the spin/charge conductance of edge states. These findings not only provide a new platform to better understand the underlying origin of QSH effect in functionalized group-V films, but also are highly desirable to design large-gap QSH insulators for practical applications in spintronics.
Adaptive evolution of a hyperthermophilic archaeon pinpoints a formate transporter as a critical factor for the growth enhancement on formate
Authors: Jung Hae-Chang , Lee Seong Hyuk , Lee Sung-Mok , An Young Jun , Lee Jung-Hyun , Lee Hyun Sook , Kang Sung Gyun 
Published: July 2017

AbstractPreviously, we reported that the hyperthermophilic archaeon Thermococcus onnurineus NA1 could grow on formate and produce H2. Formate conversion to hydrogen was mediated by a formate-hydrogen lyase complex and was indeed a part of chemiosmotic coupling to ATP generation. In this study, we employed an adaptation approach to enhance the cell growth on formate and investigated molecular changes. As serial transfer continued on formate-containing medium at the serum vial, cell growth, H2 production and formate consumption increased remarkably. The 156 times transferred-strain, WTF-156T, was demonstrated to enhance H2 production using formate in a bioreactor. The whole-genome sequencing of the WTF-156T strain revealed eleven mutations. While no mutation was found among the genes encoding formate hydrogen lyase, a point mutation (G154A) was identified in a formate transporter (TON_1573). The TON_1573 (A52T) mutation, when introduced into the parent strain, conferred increase in formate consumption and H2 production. Another adaptive passage, carried out by culturing repeatedly in a bioreactor, resulted in a strain, which has a mutation in TON_1573 (C155A) causing amino acid change, A52E. These results implicate that substitution of A52 residue of a formate transporter might be a critical factor to ensure the increase in formate uptake and cell growth.
The permeability of fractured rocks in pressurised volcanic and geothermal systems
Authors: Lamur A. , Kendrick J. E. , Eggertsson G. H. , Wall R. J. , Ashworth J. D. , Lavallée Y. 
Published: July 2017

AbstractThe connectivity of rocks’ porous structure and the presence of fractures influence the transfer of fluids in the Earth’s crust. Here, we employed laboratory experiments to measure the influence of macro-fractures and effective pressure on the permeability of volcanic rocks with a wide range of initial porosities (1–41 vol. %) comprised of both vesicles and micro-cracks. We used a hand-held permeameter and hydrostatic cell to measure the permeability of intact rock cores at effective pressures up to 30 MPa; we then induced a macro-fracture to each sample using Brazilian tensile tests and measured the permeability of these macro-fractured rocks again. We show that intact rock permeability increases non-linearly with increasing porosity and decreases with increasing effective pressure due to compactional closure of micro-fractures. Imparting a macro-fracture both increases the permeability of rocks and their sensitivity to effective pressure. The magnitude of permeability increase induced by the macro-fracture is more significant for dense rocks. We finally provide a general equation to estimate the permeability of intact and fractured rocks, forming a basis to constrain fluid flow in volcanic and geothermal systems.
CD56 Is a Pathogen Recognition Receptor on Human Natural Killer Cells
Authors: Ziegler Sabrina , Weiss Esther , Schmitt Anna-Lena , Schlegel Jan , Burgert Anne , Terpitz Ulrich , Sauer Markus , Moretta Lorenzo , Sivori Simona , Leonhardt Ines , Kurzai Oliver , Einsele Hermann , Loeffler Juergen 
Published: July 2017

AbstractAspergillus(A.)fumigatusis an opportunistic fungal mold inducing invasive aspergillosis (IA) in immunocompromised patients. Although antifungal activity of human natural killer (NK) cells was shown in previous studies, the underlying cellular mechanisms and pathogen recognition receptors (PRRs) are still unknown. Using flow cytometry we were able to show that the fluorescence positivity of the surface receptor CD56 significantly decreased upon fungal contact. To visualize the interaction site of NK cells andA.fumigatuswe used SEM, CLSM anddSTORM techniques, which clearly demonstrated that NK cells directly interact withA.fumigatusvia CD56 and that CD56 is re-organized and accumulated at this interaction site time-dependently. The inhibition of the cytoskeleton showed that the receptor re-organization was an active process dependent on actin re-arrangements. Furthermore, we could show that CD56 plays a role in the fungus mediated NK cell activation, since blocking of CD56 surface receptor reduced fungal mediated NK cell activation and reduced cytokine secretion. These results confirmed the direct interaction of NK cells andA.fumigatus, leading to the conclusion that CD56 is a pathogen recognition receptor. These findings give new insights into the functional role of CD56 in the pathogen recognition during the innate immune response.
Charge Injection, Carriers Recombination and HOMO Energy Level Relationship in Perovskite Solar Cells
Authors: Jiménez-López Jesús , Cambarau Werther , Cabau Lydia , Palomares Emilio 
Published: July 2017

AbstractWe present a comparative study between a series of well-known semiconductor polymers, used in efficient organic solar cells as hole transport materials (HTM), and the state-of-the art material used as hole transport material in perovskite solar cells: the spiro-OMeTAD. The observed differences in solar cell efficiencies are studied in depth using advanced photoinduced spectroscopic techniques under working illumination conditions. We have observed that there is no correlation between the highest occupied molecular orbital (HOMO) energy levels of the organic semiconductors and the measured open-circuit voltage (VOC). For instance, spiro-OMeTAD and P3HT have a comparable HOMO level of ~5.2 eV vs vacuum even though a difference in VOC of around 200 mV is recorded. This difference is in good agreement with the shift observed for the charge vs voltage measurements. Moreover, hole transfer from the perovskite to the HTM, estimated qualitatively from fluorescence quenching and emission lifetime, seems less efficient for the polymeric HTMs. Finally, the recombination currents from all devices were estimated by using the measured charge (calculated using photoinduced differential charging) and the carriers’ lifetime and their value resulted in accordance with the registered short-circuit currents (JSC) at 1 sun.
Therapeutic effects of sphingosine kinase inhibitor N,N-dimethylsphingosine (DMS) in experimental chronic Chagas disease cardiomyopathy
Authors: Vasconcelos Juliana Fraga , Meira Cássio Santana , Silva Daniela Nascimento , Nonaka Carolina Kymie Vasques , Daltro Pâmela Santana , Macambira Simone Garcia , Domizi Pablo Daniel , Borges Valéria Matos , Ribeiro-dos-Santos Ricardo , de Freitas Souza Bruno Solano , Soares Milena Botelho Pereira 
Published: July 2017

AbstractChagas disease cardiomyopathy is a parasite-driven inflammatory disease to which there are no effective treatments. Here we evaluated the therapeutic potential of N,N-dimethylsphingosine(DMS), which blocks the production of sphingosine-1-phosphate(S1P), a mediator of cellular events during inflammatory responses, in a model of chronic Chagas disease cardiomyopathy. DMS-treated, Trypanosoma cruzi-infected mice had a marked reduction of cardiac inflammation, fibrosis and galectin-3 expression when compared to controls. Serum concentrations of galectin-3, IFNγ and TNFα, as well as cardiac gene expression of inflammatory mediators were reduced after DMS treatment. The gene expression of M1 marker, iNOS, was decreased, while the M2 marker, arginase1, was increased. DMS-treated mice showed an improvement in exercise capacity. Moreover, DMS caused a reduction in parasite load in vivo. DMS inhibited the activation of lymphocytes, and reduced cytokines and NO production in activated macrophage cultures in vitro, while increasing IL-1β production. Analysis by qRT-PCR array showed that DMS treatment modulated inflammasome activation induced by T. cruzi on macrophages. Altogether, our results demonstrate that DMS, through anti-parasitic and immunomodulatory actions, can be beneficial in the treatment of chronic phase of T. cruzi infection and suggest that S1P-activated processes as possible therapeutic targets for the treatment of Chagas disease cardiomyopathy.