bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy-efficient CO2 hydrogenation with fast response using photoexcitation of CO2 adsorbed on metal catalysts
Authors: Kim Chanyeon , Hyeon Seokwon , Lee Jonghyeok , Kim Whi Dong , Lee Doh C. , Kim Jihan , Lee Hyunjoo 
Published: July 2018

AbstractMany heterogeneous catalytic reactions occur at high temperatures, which may cause large energy costs, poor safety, and thermal degradation of catalysts. Here, we propose a light-assisted surface reaction, which catalyze the surface reaction using both light and heat as an energy source. Conventional metal catalysts such as ruthenium, rhodium, platinum, nickel, and copper were tested for CO2 hydrogenation, and ruthenium showed the most distinct change upon light irradiation. CO2 was strongly adsorbed onto ruthenium surface, forming hybrid orbitals. The band gap energy was reduced significantly upon hybridization, enhancing CO2 dissociation. The light-assisted CO2 hydrogenation used only 37% of the total energy with which the CO2 hydrogenation occurred using only thermal energy. The CO2 conversion could be turned on and off completely with a response time of only 3 min, whereas conventional thermal reaction required hours. These unique features can be potentially used for on-demand fuel production with minimal energy input.
Broadband Variable Meta-Axicons Based on Nano-Aperture Arrays in a Metallic Film
Authors: Zhu Yunzhi , Wei Dunzhao , Kuang Zeyu , Wang Qianjin , Wang Yongmei , Huang Xiaoyang , Zhang Yong , Xiao Min 
Published: July 2018

AbstractMetasurfaces are two-dimensional metamaterials composed of a carefully designed series of subwavelength meta-atom (antenna or aperture) arrays. These surfaces can manipulate the phase, amplitude and polarization of output light by changing the shapes and orientations of the meta-atoms on a subwavelength scale. Using these properties, we experimentally demonstrate variable meta-axicons composed of rectangular nano-apertures arranged in several concentric rings that can focus left circularly polarized (LCP) light into a real Bessel beam and defocus right circular polarized (RCP) light to form a virtual beam. A desired phase discontinuity in cross-polarized transmitted light is introduced along the interface by controlling the orientations of the nano-apertures. In addition, the meta-axicons can generate Bessel beams of arbitrary orders by suitable design of the phase profile along the surface. The meta-axicons demonstrate broadband optical properties that can switch the wavelength of the incident light from 690 nm to 1050 nm. These variable meta-axicons open a path towards the development of new applications using integrated beam shaping devices.
TNF-α increases the intrinsic excitability of cerebellar Purkinje cells through elevating glutamate release in Bergmann Glia
Authors: Shim Hyun Geun , Jang Sung-Soo , Kim Seung Ha , Hwang Eun Mi , Min Joo Ok , Kim Hye Yun , Kim Yoo Sung , Ryu Changhyeon , Chung Geehoon , Kim YoungSoo , Yoon Bo-Eun , Kim Sang Jeong 
Published: July 2018

AbstractFor decades, the glial function has been highlighted not only as the ‘structural glue’, but also as an ‘active participant’ in neural circuits. Here, we suggest that tumor necrosis factor α (TNF-α), a key inflammatory cytokine, alters the neural activity of the cerebellar Purkinje cells (PCs) by facilitating gliotransmission in the juvenile male rat cerebellum. A bath application of TNF-α (100 ng/ml) in acute cerebellar slices elevates spiking activity of PCs with no alterations in the regularity of PC firings. Interestingly, the effect of TNF-α on the intrinsic excitability of PCs was abolished under a condition in which the type1 TNF receptor (TNFR1) in Bergmann glia (BG) was genetically suppressed by viral delivery of an adeno-associated virus (AAV) containing TNFR1-shRNA. In addition, we measured the concentration of glutamate derived from dissociated cerebellar cortical astrocyte cultures treated with TNF-α and observed a progressive increase of glutamate in a time-dependent manner. We hypothesised that TNF-α-induced elevation of glutamate from BGs enveloping the synaptic cleft may directly activate metabotropic glutamate receptor1 (mGluR1). Pharmacological inhibition of mGluR1, indeed, prevented the TNF-α-mediated elevation of the intrinsic excitability in PCs. Taken together, our study reveals that TNF-α triggers glutamate release in BG, thereby increasing the intrinsic excitability of cerebellar PCs in a mGluR1-dependent manner.
Photon Energy Dependent Micro-Raman Spectroscopy with a Continuum Laser Source
Authors: Krause Stefan , Overgaard Marc H. , Vosch Tom 
Published: July 2018

AbstractWe present a method for continuous, photon energy dependent micro Raman spectroscopy. A narrow excitation line is selected from a continuum laser by an acousto-optic tunable filter (AOTF) plus an additional monochromator (MC). Automation of laser, AOTF, MC and tunable long pass filters enables us to continuously scan the wavelength over the full visible range while synchronously acquiring Raman spectra over a photon energy range from 1.85 eV to 2.83 eV. We demonstrate the applicability of our method on a well-studied sample, reduced graphene oxide (rGO), where we measure the Raman scattering over the whole visual range and use the photon energy dependence of the D, G and GS band as verification for the method we present here. We complement this set of data with additional results from a Ti:sapphire laser source, covering the 1.75 to 1.41 eV range. From the full photon energy range of 1.41 to 2.83 eV, we noticed a small deviation from linearity for the dispersion of the D band.
Direct imaging of uncoated biological samples enables correlation of super-resolution and electron microscopy data
Authors: Mateos José María , Barmettler Gery , Doehner Jana , Kaech Andres , Ziegler Urs 
Published: July 2018

AbstractA simple method for imaging biological tissue samples by electron microscopy and its correlation with super-resolution light microscopy is presented. This room temperature protocol, based on protecting thin biological specimens with methylcellulose and imaging with low voltage scanning electron microscopy, circumvents complex classical electron microscopy sample preparation steps requiring dehydration, resin embedding and use of contrast agents. This technique facilitates visualization of subcellular structures e.g. synaptic clefts and synaptic vesicles in mouse brain tissue and the organization of mitochondrial cristae in the zebrafish retina. Application of immunogold protocols to these samples can determine the precise localization of synaptic proteins and, in combination with super-resolution light microscopy methods clearly pinpoints the subcellular distribution of several proteins in the tissue. The simplicity of the method, including section collection on a silicon wafer, reduces artefacts and correlates protein location with sample morphology.
Gecko-Inspired Biocidal Organic Nanocrystals Initiated from a Pencil-Drawn Graphite Template
Authors: Gonzalez Arellano David L. , Kolewe Kristopher W. , Champagne Victor K. , Kurtz Irene S. , Burnett Edmund K. , Zakashansky Julia A. , Arisoy Feyza Dundar , Briseno Alejandro L. , Schiffman Jessica D. 
Published: July 2018

AbstractThe biocidal properties of gecko skin and cicada wings have inspired the synthesis of synthetic surfaces decorated with high aspect ratio nanostructures that inactivate microorganisms. Here, we investigate the bactericidal activity of oriented zinc phthalocyanine (ZnPc) nanopillars grown using a simple pencil-drawn graphite templating technique. By varying the evaporation time, nanopillars initiated from graphite that was scribbled using a pencil onto silicon substrates were optimized to yield a high inactivation of the Gram-negative bacteria, Escherichia coli. We next adapted the procedure so that analogous nanopillars could be grown from pencil-drawn graphite scribbled onto stainless steel, flexible polyimide foil, and glass substrates. Time-dependent bacterial cytotoxicity studies indicate that the oriented nanopillars grown on all four substrates inactivated up to 97% of the E. coli quickly, in 15 min or less. These results suggest that organic nanostructures, which can be easily grown on a broad range of substrates hold potential as a new class of biocidal surfaces that kill microbes quickly and potentially, without spreading antibiotic-resistance genes.
Golden Ratio Gain Enhancement in Coherently Coupled Parametric Processes
Authors: Jedrkiewicz Ottavia , Gatti Alessandra , Brambilla Enrico , Levenius Martin , Tamošauskas Gintaras , Gallo Katia 
Published: July 2018

AbstractNonlinear optical processes are an essential tool in modern optics, with a broad spectrum of applications, including signal processing, frequency conversion, spectroscopy and quantum optics. Ordinary parametric devices nevertheless still suffer from relatively low gains and wide spectral emission. Here we demonstrate a unique configuration for phase-matching multiple nonlinear processes in a monolithic 2D nonlinear photonic crystal, resulting in the coherent parametric emission of four signal and idler modes, featuring an exponential gain enhancement equal to the Golden Ratio. The results indicate a new route towards compact high-brightness and coherent sources for multi-photon generation, manipulation and entanglement, overcoming limitations of conventional parametric devices.
Loss of the fragile X mental retardation protein causes aberrant differentiation in human neural progenitor cells
Authors: Sunamura Naohiro , Iwashita Shinzo , Enomoto Kei , Kadoshima Taisuke , Isono Fujio 
Published: July 2018

AbstractFragile X syndrome (FXS) is caused by transcriptional silencing of the FMR1 gene during embryonic development with the consequent loss of the encoded fragile X mental retardation protein (FMRP). The pathological mechanisms of FXS have been extensively studied using the Fmr1-knockout mouse, and the findings suggest important roles for FMRP in synaptic plasticity and proper functioning of neural networks. However, the function of FMRP during early development in the human nervous system remains to be confirmed. Here we describe human neural progenitor cells (NPCs) as a model for studying FMRP functions and FXS pathology. Transcriptome analysis of the NPCs derived from FMR1-knockout human induced pluripotent stem cells (iPSCs) showed altered expression of neural differentiation markers, particularly a marked induction of the astrocyte marker glial fibrillary acidic protein (GFAP). When induced to differentiate, FMRP-deficient neurons continued to express GFAP, and showed less spontaneous calcium bursts than the parental iPSC-derived neurons. Interestingly, the aberrant expression of GFAP and the impaired firing was corrected by treatment with the protein kinase inhibitor LX7101. These findings underscore the modulatory roles of FMRP in human neurogenesis, and further demonstrate that the defective phenotype of FXS could be reversed at least partly by small molecule kinase inhibitors.
In-situ ATR-FTIR for dynamic analysis of superhydrophobic breakdown on nanostructured silicon surfaces
Authors: Vrancken Nandi , Li Jiaqi , Sergeant Stefanie , Vereecke Guy , Doumen Geert , Holsteyns Frank , Chen Chang , Terryn Herman , De Gendt Stefan , Xu XiuMei 
Published: July 2018

AbstractSuperhydrophobic surfaces are highly promising for self-cleaning, anti-fouling and anti-corrosion applications. However, accurate assessment of the lifetime and sustainability of super-hydrophobic materials is hindered by the lack of large area characterization of superhydrophobic breakdown. In this work, attenuated total reflectance−Fourier transform infrared spectroscopy (ATR-FTIR) is explored for a dynamic study of wetting transitions on immersed superhydrophobic arrays of silicon nanopillars. Spontaneous breakdown of the superhydrophobic state is triggered by in-situ modulation of the liquid surface tension. The high surface sensitivity of ATR-FTIR allows for accurate detection of local liquid infiltration. Experimentally determined wetting transition criteria show significant deviations from predictions by classical wetting models. Breakdown kinetics is found to slow down dramatically when the liquid surface tension approaches the transition criterion, which clearly underlines the importance of more accurate wetting analysis on large-area surfaces. Precise actuation of the superhydrophobic breakdown process is demonstrated for the first time through careful modulation of the liquid surface tension around the transition criterion. The developed ATR-FTIR method can be a promising technique to study wetting transitions and associated dynamics on various types of superhydrophobic surfaces.
Gastrojejunal anastomosis in rats using the magnetic compression technique
Authors: An Yingfeng , Zhang Yanchao , Liu Hao , Ma Sijie , Fu Shan , Lv Yi , Yan Xiaopeng 
Published: July 2018

AbstractRats are suitable animal models in which to study the effects of gastric bypass surgery. However, construction of gastrojejunal anastomosis in the rat is technically demanding and is associated with high rate of postoperative complications. The aim of this study was to explore the feasibility and efficacy of the magnetic compression technique (MCT) in side-to-side gastrojejunal anastomosis in rats. Thirty male rats underwent gastrojejunal anastomosis using one of three techniques: hand-sewn, magnetic compression using cuboid magnets, and magnetic compression using magnetic rings. The mean anastomosis time using the magnetic compression technique was significantly less than that of the hand-sewn technique (3.6 ± 0.96 and 6.50 ± 1.58 vs. 14.40 ± 2.37 minutes,). The survival rate was highest in animals treated with magnetic compression using cuboid magnets (100%), followed by animals treated with magnetic compression using magnetic rings (90%) and then hand sewing (70%). The mean burst pressure did not differ significantly between the magnetic compression and hand-sewn anastomoses. Anastomoses constructed by magnetic compression were smoother and flatter than hand-sewn anastomoses. The results showed that MCT is a simple and feasible method for gastrojejunal anastomosis in the rat.
High prevalence of hepatitis delta virus in Cameroon
Authors: Butler Emily K. , Rodgers Mary A. , Coller Kelly E. , Barnaby Devin , Krilich Elizabeth , Olivo Ana , Cassidy Michael , Mbanya Dora , Kaptue Lazare , Ndembi Nicaise , Cloherty Gavin 
Published: July 2018

AbstractHepatitis delta virus (HDV), a satellite virus of hepatitis B virus (HBV), infects an estimated 15–20 million people worldwide and confers a greater risk for accelerated progression to liver disease. However, limited HDV surveillance data are available in sub-Saharan Africa where HDV diversity is high. To determine the prevalence and diversity of HDV in Cameroon, serological and molecular characterization was performed on 1928 HBsAg positive specimens selected from retrospective viral surveillance studies conducted in Cameroon from 2010–2016. Samples were screened for HDV antibodies on the Abbott ARCHITECT instrument and for HDV RNA on the Abbott m2000 instrument by research assays. HDV positive specimens with sufficient viral load were selected for genomic sequencing. The seroprevalence of HDV in HBsAg positive samples from Cameroon was 46.73% [95% CI; 44.51–48.96%], with prevalence of active HDV infection being 34.2% [95% CI; 32.09–36.41%]. HDV genotypes 1, 6, 7 and 8 were identified amongst N = 211 sequences, including N = 145 genomes. HDV prevalence is high within the study cohort, indicating that a large portion of HBV infected individuals in Cameroon are at elevated risk for severe hepatitis and death. Collectively, these results emphasize the need for HBV vaccination and HDV testing in HBsAg positive patients in Cameroon.
Slow rewarming improved the neurological outcomes of prolonged mild therapeutic hypothermia in patients with severe traumatic brain injury and an evacuated hematoma
Authors: Kaneko Tadashi , Fujita Motoki , Yamashita Susumu , Oda Yasutaka , Suehiro Eiichi , Dohi Kenji , Kasaoka Shunji , Kuroda Yasuhiro , Kobata Hitoshi , Maekawa Tsuyoshi 
Published: July 2018

AbstractMild therapeutic hypothermia (MTH) is expected to improve the neurological outcomes of patients with severe traumatic brain injury (TBI). However, there are no standard protocols for managing the temperature of patients with severe TBI in order to improve their neurological outcomes. We conducted a post hoc analysis of the B-HYPO study, a randomized controlled trial of MTH in patients with TBI in Japan. We evaluated the impact of MTH methods on neurological outcomes. Ninety-seven patients who received MTH were included in the present analyses. The neurological outcomes were compared among subgroups of patients divided by cutoff values for the induction, maintenance, and rewarming times of MTH in all patients, in patients with diffuse injury, and in patients with an evacuated hematoma. The proportion of patients with a good neurological outcome was significantly different between patients with an evacuated hematoma divided into subgroups by the cutoff value of rewarming time of 48 h (>48 h vs. ≤ 48 h: 65% vs. 22%; odds ratio: 6.61; 95% confidence interval: 1.13–38.7, P = 0.0498). Slow rewarming for >48 h might improve the neurological outcomes of prolonged MTH in patients with TBI and an evacuated hematoma. Further studies are needed to investigate the optimal rewarming protocol in patients with TBI.
A platform for phenotypic discovery of therapeutic antibodies and targets applied on Chronic Lymphocytic Leukemia
Authors: Ljungars A. , Mårtensson L. , Mattsson J. , Kovacek M. , Sundberg A. , Tornberg U-C. , Jansson B. , Persson N. , Emruli V. Kuci , Ek S. , Jerkeman M. , Hansson M. , Juliusson G. , Ohlin M. , Frendéus B. , Teige I. , Mattsson M. 
Published: July 2018

AbstractDevelopment of antibody drugs against novel targets and pathways offers great opportunities to improve current cancer treatment. We here describe a phenotypic discovery platform enabling efficient identification of therapeutic antibody-target combinations. The platform utilizes primary patient cells throughout the discovery process and includes methods for differential phage display cell panning, high-throughput cell-based specificity screening, phenotypic in vitro screening, target deconvolution, and confirmatory in vivo screening. In this study the platform was applied on cancer cells from patients with Chronic Lymphocytic Leukemia resulting in discovery of antibodies with improved cytotoxicity in vitro compared to the standard of care, the CD20-specific monoclonal antibody rituximab. Isolated antibodies were found to target six different receptors on Chronic Lymphocytic Leukemia cells; CD21, CD23, CD32, CD72, CD200, and HLA-DR of which CD32, CD200, and HLA-DR appeared as the most potent targets for antibody-based cytotoxicity treatment. Enhanced antibody efficacy was confirmed in vivo using a patient-derived xenograft model.
Androgen receptor degradation by the proteolysis-targeting chimera ARCC-4 outperforms enzalutamide in cellular models of prostate cancer drug resistance
Authors: Salami Jemilat , Alabi Shanique , Willard Ryan R. , Vitale Nick J. , Wang Jing , Dong Hanqing , Jin Meizhong , McDonnell Donald P. , Crew Andrew P. , Neklesa Taavi K. , Crews Craig M. 
Published: July 2018

AbstractThe androgen receptor is a major driver of prostate cancer and inhibition of its transcriptional activity using competitive antagonists, such as enzalutamide remains a frontline therapy for prostate cancer management. However, the majority of patients eventually develop drug resistance. We propose that targeting the androgen receptor for degradation via Proteolysis Targeting Chimeras (PROTACs) will be a better therapeutic strategy for targeting androgen receptor signaling in prostate cancer cells. Here we perform a head-to-head comparison between a currently approved androgen receptor antagonist enzalutamide, and its PROTAC derivative, ARCC-4, across different cellular models of prostate cancer drug resistance. ARCC-4 is a low-nanomolar androgen receptor degrader able to degrade about 95% of cellular androgen receptors. ARCC-4 inhibits prostate tumor cell proliferation, degrades clinically relevant androgen receptor point mutants and unlike enzalutamide, retains antiproliferative effect in a high androgen environment. Thus, ARCC-4 exemplifies how protein degradation can address the drug resistance hurdles of enzalutamide.
Four winters of photometry with ASTEP South at Dome C, Antarctica
Authors: Crouzet N. , Chapellier E. , Guillot T. , Mékarnia D. , Agabi A. , Fanteï-Caujolle Y. , Abe L. , Rivet J.-P. , Schmider F.-X. , Fressin F. , Bondoux E. , Challita Z. , Pouzenc C. , Valbousquet F. , Bayliss D. , Bonhomme S. , Daban J.-B. , Gouvret C. , Blazit A. 
Published: July 2018

Context. Dome C in Antarctica is a promising site for photometric observations thanks to the continuous night during the Antarctic winter and favorable weather conditions.
Aims.We developed instruments to assess the quality of this site for photometry in the visible and to detect and characterize variable objects through the Antarctic Search for Transiting ExoPlanets (ASTEP) project.
Methods. Here, we present the full analysis of four winters of data collected with ASTEP South, a 10 cm refractor pointing continuously toward the celestial south pole. We improved the instrument over the years and developed specific data reduction methods.
Results. We achieved nearly continuous observations over the winters. We measure an average sky background of 20 mag arcsec−2 in the 579–642 nm bandpass. We built the lightcurves of 6000 stars and developed a model to infer the photometric quality of Dome C from the lightcurves themselves. The weather is photometric 67.1 ± 4.2% of the time and veiled 21.8 ± 2.0% of the time. The remaining time corresponds to poor quality data or winter storms. We analyzed the lightcurves of σ Oct and HD 184465 and find that the amplitude of their main frequency varies by a factor of 3.5 and 6.7 over the four years, respectively. We also identify 34 new variable stars and eight new eclipsing binaries with periods ranging from 0.17 to 81 days.
Conclusion. The phase coverage that we achieved with ASTEP South is exceptional for a ground-based instrument and the data quality enables the detection and study of variable objects. These results demonstrate the high quality of Dome C for photometry in the visible and for time series observations in general.