bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D-Printing of Meso-structurally Ordered Carbon Fiber/Polymer Composites with Unprecedented Orthotropic Physical Properties
Authors: Lewicki James P. , Rodriguez Jennifer N. , Zhu Cheng , Worsley Marcus A. , Wu Amanda S. , Kanarska Yuliya , Horn John D. , Duoss Eric B. , Ortega Jason M. , Elmer William , Hensleigh Ryan , Fellini Ryan A. , King Michael J. 
Published: March 2017

AbstractHere we report the first example of a class of additively manufactured carbon fiber reinforced composite (AMCFRC) materials which have been achieved through the use of a latent thermal cured aromatic thermoset resin system, through an adaptation of direct ink writing (DIW) 3D-printing technology. We have developed a means of printing high performance thermoset carbon fiber composites, which allow the fiber component of a resin and carbon fiber fluid to be aligned in three dimensions via controlled micro-extrusion and subsequently cured into complex geometries. Characterization of our composite systems clearly show that we achieved a high order of fiber alignment within the composite microstructure, which in turn allows these materials to outperform equivalently filled randomly oriented carbon fiber and polymer composites. Furthermore, our AM carbon fiber composite systems exhibit highly orthotropic mechanical and electrical responses as a direct result of the alignment of carbon fiber bundles in the microscale which we predict will ultimately lead to the design of truly tailorable carbon fiber/polymer hybrid materials having locally programmable complex electrical, thermal and mechanical response.
Multifunctional Nano-engineered Polymer Surfaces with Enhanced Mechanical Resistance and Superhydrophobicity
Authors: Hernández Jaime J. , Monclús Miguel A. , Navarro-Baena Iván , Viela Felipe , Molina-Aldareguia Jon M. , Rodríguez Isabel 
Published: March 2017

AbstractThis paper presents a multifunctional polymer surface that provides superhydrophobicity and self–cleaning functions together with an enhancement in mechanical and electrical performance. These functionalities are produced by nanoimprinting high aspect ratio pillar arrays on polymeric matrix incorporating functional reinforcing elements. Two distinct matrix-filler systems are investigated specifically, Carbon Nanotube reinforced Polystyrene (CNT-PS) and Reduced Graphene Oxide reinforced Polyvinylidene Difluoride (RGO-PVDF). Mechanical characterization of the topographies by quantitative nanoindentation and nanoscratch tests are performed to evidence a considerable increase in stiffness, Young’s modulus and critical failure load with respect to the pristine polymers. The improvement on the mechanical properties is rationalized in terms of effective dispersion and penetration of the fillers into the imprinted structures as determined by confocal Raman and SEM studies. In addition, an increase in the degree of crystallization for the PVDF-RGO imprinted nanocomposite possibly accounts for the larger enhancement observed. Improvement of the mechanical ruggedness of functional textured surfaces with appropriate fillers will enable the implementation of multifunctional nanotextured materials in real applications.
A 3D self-organizing multicellular epidermis model of barrier formation and hydration with realistic cell morphology based on EPISIM
Authors: Sütterlin Thomas , Tsingos Erika , Bensaci Jalil , Stamatas Georgios N. , Grabe Niels 
Published: March 2017

AbstractThe epidermis and the stratum corneum (SC) as its outermost layer have evolved to protect the body from evaporative water loss to the environment. To morphologically represent the extremely flattened cells of the SC - and thereby the epidermal barrier - in a multicellular computational model, we developed a 3D biomechanical model (BM) based on ellipsoid cell shapes. We integrated the BM in the multicellular modelling and simulation platform EPISIM. We created a cell behavioural model (CBM) with EPISIM encompassing regulatory feedback loops between the epidermal barrier, water loss to the environment, and water and calcium flow within the tissue. This CBM allows a small number of stem cells to initiate self-organizing epidermal stratification, yielding the spontaneous emergence of water and calcium gradients comparable to experimental data. We find that the 3D in silico epidermis attains homeostasis most quickly at high ambient humidity, and once in homeostasis the epidermal barrier robustly buffers changes in humidity. Our model yields an in silico epidermis with a previously unattained realistic morphology, whose cell neighbour topology is validated with experimental data obtained from in vivo images. This work paves the way to computationally investigate how an impaired SC barrier precipitates disease.
Polarization-controlled optimal scatter suppression in transient absorption spectroscopy
Authors: Malý Pavel , Ravensbergen Janneke , Kennis John T. M. , van Grondelle Rienk , Croce Roberta , Mančal Tomáš , van Oort Bart 
Published: March 2017

AbstractUltrafast transient absorption spectroscopy is a powerful technique to study fast photo-induced processes, such as electron, proton and energy transfer, isomerization and molecular dynamics, in a diverse range of samples, including solid state materials and proteins. Many such experiments suffer from signal distortion by scattered excitation light, in particular close to the excitation (pump) frequency. Scattered light can be effectively suppressed by a polarizer oriented perpendicular to the excitation polarization and positioned behind the sample in the optical path of the probe beam. However, this introduces anisotropic polarization contributions into the recorded signal. We present an approach based on setting specific polarizations of the pump and probe pulses, combined with a polarizer behind the sample. Together, this controls the signal-to-scatter ratio (SSR), while maintaining isotropic signal. We present SSR for the full range of polarizations and analytically derive the optimal configuration at angles of 40.5° between probe and pump and of 66.9° between polarizer and pump polarizations. This improves SSR by "Equation missing" (or "Equation missing" compared to polarizer parallel to probe). The calculations are validated by transient absorption experiments on the common fluorescent dye Rhodamine B. This approach provides a simple method to considerably improve the SSR in transient absorption spectroscopy.
Iteration expansion and regional evolution: phylogeography of Dendrobium officinale and four related taxa in southern China
Authors: Hou Beiwei , Luo Jing , Zhang Yusi , Niu Zhitao , Xue Qingyun , Ding Xiaoyu 
Published: March 2017

AbstractThe genusDendrobiumwas used as a case study to elucidate the evolutionary history of Orchidaceae in the Sino-Japanese Floristic Region (SJFR) and Southeast Asia region. These evolutionary histories remain largely unknown, including the temporal and spatial distribution of the evolutionary events. The present study used nuclear and plastid DNA to determine the phylogeography ofDendrobium officinaleand four closely related taxa. Plastid DNA haplotype and nuclear data were shown to be discordant, suggesting reticulate evolution drove the species’ diversification. Rapid radiation and genetic drift appeared to drive the evolution ofD. tosaenseandD. flexicaule, whereas introgression or hybridization might have been involved in the evolution ofD. scoriarumandD. shixingense. The phylogeographical structure ofD. officinalerevealed that core natural distribution regions might have served as its glacial refuges. In recent years, human disturbances caused its artificial migration and population extinction. The five taxa may have originated from the Nanling Mountains and the Yungui Plateau and then migrated northward or eastward. After the initial iteration expansion,D. officinalepopulations appeared to experience the regional evolutionary patterns in different regions and follow the sequential or rapid decline in gene exchange.
Manipulation of a Nuclear Spin by a Magnetic Domain Wall in a Quantum Hall Ferromagnet
Authors: Korkusinski M. , Hawrylak P. , Liu H. W. , Hirayama Y. 
Published: March 2017

AbstractThe manipulation of a nuclear spin by an electron spin requires the energy to flip the electron spin to be vanishingly small. This can be realized in a many electron system with degenerate ground states of opposite spin polarization in different Landau levels. We present here a microscopic theory of a domain wall between spin unpolarized and spin polarized quantum Hall ferromagnet states at filling factor two with the Zeeman energy comparable to the cyclotron energy. We determine the energies and many-body wave functions of the electronic quantum Hall droplet with up to N = 80 electrons as a function of the total spin, angular momentum, cyclotron and Zeeman energies from the spin singlet ν = 2 phase, through an intermediate polarization state exhibiting a domain wall to the fully spin-polarized phase involving the lowest and the second Landau levels. We demonstrate that the energy needed to flip one electron spin in a domain wall becomes comparable to the energy needed to flip the nuclear spin. The orthogonality of orbital electronic states is overcome by the many-electron character of the domain - the movement of the domain wall relative to the position of the nuclear spin enables the manipulation of the nuclear spin by electrical means.
Conserved intergenic sequences revealed by CTAG-profiling in Salmonella: thermodynamic modeling for function prediction
Authors: Tang Le , Zhu Songling , Mastriani Emilio , Fang Xin , Zhou Yu-Jie , Li Yong-Guo , Johnston Randal N. , Guo Zheng , Liu Gui-Rong , Liu Shu-Lin 
Published: March 2017

AbstractHighly conserved short sequences help identify functional genomic regions and facilitate genomic annotation. We used Salmonella as the model to search the genome for evolutionarily conserved regions and focused on the tetranucleotide sequence CTAG for its potentially important functions. In Salmonella, CTAG is highly conserved across the lineages and large numbers of CTAG-containing short sequences fall in intergenic regions, strongly indicating their biological importance. Computer modeling demonstrated stable stem-loop structures in some of the CTAG-containing intergenic regions, and substitution of a nucleotide of the CTAG sequence would radically rearrange the free energy and disrupt the structure. The postulated degeneration of CTAG takes distinct patterns among Salmonella lineages and provides novel information about genomic divergence and evolution of these bacterial pathogens. Comparison of the vertically and horizontally transmitted genomic segments showed different CTAG distribution landscapes, with the genome amelioration process to remove CTAG taking place inward from both terminals of the horizontally acquired segment.
Continual Antigenic Diversification in China Leads to Global Antigenic Complexity of Avian Influenza H5N1 Viruses
Authors: Peng Yousong , Li Xiaodan , Zhou Hongbo , Wu Aiping , Dong Libo , Zhang Ye , Gao Rongbao , Bo Hong , Yang Lei , Wang Dayan , Lin Xian , Jin Meilin , Shu Yuelong , Jiang Taijiao 
Published: March 2017

AbstractThe highly pathogenic avian influenza (HPAI) H5N1 virus poses a significant potential threat to human society due to its wide spread and rapid evolution. In this study, we present a comprehensive antigenic map for HPAI H5N1 viruses including 218 newly sequenced isolates from diverse regions of mainland China, by computationally separating almost all HPAI H5N1 viruses into 15 major antigenic clusters (ACs) based on their hemagglutinin sequences. Phylogenetic analysis showed that 12 of these 15 ACs originated in China in a divergent pattern. Further analysis of the dissemination of HPAI H5N1 virus in China identified that the virus’s geographic expansion was co-incident with a significant divergence in antigenicity. Moreover, this antigenic diversification leads to global antigenic complexity, as typified by the recent HPAI H5N1 spread, showing extensive co-circulation and local persistence. This analysis has highlighted the challenge in H5N1 prevention and control that requires different planning strategies even inside China.
Characterization of cholesterol homeostasis in sphingosine-1-phosphate lyase-deficient fibroblasts reveals a Niemann-Pick disease type C-like phenotype with enhanced lysosomal Ca2+ storage
Authors: Vienken Hans , Mabrouki Nathalie , Grabau Katja , Claas Ralf Frederik , Rudowski Agnes , Schömel Nina , Pfeilschifter Josef , Lütjohann Dieter , van Echten-Deckert Gerhild , Meyer zu Heringdorf Dagmar 
Published: March 2017

AbstractSphingosine-1-phosphate (S1P) lyase irreversibly cleaves S1P, thereby catalysing the ultimate step of sphingolipid degradation. We show here that embryonic fibroblasts from S1P lyase-deficient mice (Sgpl1−/−-MEFs), in which S1P and sphingosine accumulate, have features of Niemann-Pick disease type C (NPC) cells. In the presence of serum, overall cholesterol content was elevated inSgpl1−/−-MEFs, due to upregulation of the LDL receptor and enhanced cholesterol uptake. Despite this, activation of sterol regulatory element-binding protein-2 was increased inSgpl1−/−-MEFs, indicating a local lack of cholesterol at the ER. Indeed, free cholesterol was retained in NPC1-containing vesicles, which is a hallmark of NPC. Furthermore, upregulation of amyloid precursor protein inSgpl1−/−-MEFs was mimicked by an NPC1 inhibitor inSgpl1+/+-MEFs and reduced by overexpression of NPC1. Lysosomal pH was not altered by S1P lyase deficiency, similar to NPC. Interestingly, lysosomal Ca2+content and bafilomycin A1-induced [Ca2+]iincreases were enhanced inSgpl1−/−-MEFs, contrary to NPC. These results show that both a primary defect in cholesterol trafficking and S1P lyase deficiency cause overlapping phenotypic alterations, and challenge the present view on the role of sphingosine in lysosomal Ca2+homeostasis.
Endosymbiotic calcifying bacteria across sponge species and oceans
Authors: Garate Leire , Sureda Jan , Agell Gemma , Uriz Maria J. 
Published: March 2017

AbstractFrom an evolutionary point of view, sponges are ideal targets to study marine symbioses as they are the most ancient living metazoans and harbour highly diverse microbial communities. A recently discovered association between the spongeHemimycale columellaand an intracellular bacterium that generates large amounts of calcite spherules has prompted speculation on the possible role of intracellular bacteria in the evolution of the skeleton in early animals. To gain insight into this purportedly ancestral symbiosis, we investigated the presence of symbiotic bacteria in Mediterranean and Caribbean sponges. We found four new calcibacteria OTUs belonging to the SAR116 in two orders (Poecilosclerida and Clionaida) and three families of Demospongiae, two additional OTUs in cnidarians and one more in seawater (at 98.5% similarity). Using a calcibacteria targeted probe and CARD-FISH, we also found calcibacteria in Spirophorida and Suberitida and proved that the calcifying bacteria accumulated at the sponge periphery, forming a skeletal cortex, analogous to that of siliceous microscleres in other demosponges. Bacteria-mediated skeletonization is spread in a range of phylogenetically distant species and thus the purported implication of bacteria in skeleton formation and evolution of early animals gains relevance.
Room-temperature short-wavelength infrared Si photodetector
Authors: Berencén Yonder , Prucnal Slawomir , Liu Fang , Skorupa Ilona , Hübner René , Rebohle Lars , Zhou Shengqiang , Schneider Harald , Helm Manfred , Skorupa Wolfgang 
Published: March 2017

AbstractThe optoelectronic applications of Si are restricted to the visible and near-infrared spectral range due to its 1.12 eV-indirect band gap. Sub-band gap light detection in Si, for instance, has been a long-standing scientific challenge for many decades since most photons with sub-band gap energies pass through Si unabsorbed. This fundamental shortcoming, however, can be overcome by introducing non-equilibrium deep-level dopant concentrations into Si, which results in the formation of an impurity band allowing for strong sub-band gap absorption. Here, we present steady-state room-temperature short-wavelength infrared p-n photodiodes from single-crystalline Si hyperdoped with Se concentrations as high as 9 × 1020 cm−3, which are introduced by a robust and reliable non-equilibrium processing consisting of ion implantation followed by millisecond-range flash lamp annealing. We provide a detailed description of the material properties, working principle and performance of the photodiodes as well as the main features in the studied wavelength region. This work fundamentally contributes to establish the short-wavelength infrared detection by hyperdoped Si in the forefront of the state-of-the-art of short-IR Si photonics.
Cooperation in carbon source degradation shapes spatial self-organization of microbial consortia on hydrated surfaces
Authors: Tecon Robin , Or Dani 
Published: March 2017

AbstractMounting evidence suggests that natural microbial communities exhibit a high level of spatial organization at the micrometric scale that facilitate ecological interactions and support biogeochemical cycles. Microbial patterns are difficult to study definitively in natural environments due to complex biodiversity, observability and variable physicochemical factors. Here, we examine how trophic dependencies give rise to self-organized spatial patterns of a well-defined bacterial consortium grown on hydrated surfaces. The model consortium consisted of two Pseudomonas putida mutant strains that can fully degrade the aromatic hydrocarbon toluene. We demonstrated that obligate cooperation in toluene degradation (cooperative mutualism) favored convergence of 1:1 partner ratio and strong intermixing at the microscale (10–100 μm). In contrast, competition for benzoate, a compound degraded independently by both strains, led to distinct segregation patterns. Emergence of a persistent spatial pattern has been predicted for surface attached microbial activity in liquid films that mediate diffusive exchanges while permitting limited cell movement (colony expansion). This study of a simple microbial consortium offers mechanistic glimpses into the rules governing the assembly and functioning of complex sessile communities, and points to general principles of spatial organization with potential applications for natural and engineered microbial systems.
Manganese mono-boride, an inexpensive room temperature ferromagnetic hard material
Authors: Ma Shuailing , Bao Kuo , Tao Qiang , Zhu Pinwen , Ma Teng , Liu Bo , Liu Yazhou , Cui Tian 
Published: March 2017

AbstractWe synthesized orthorhombic FeB-type MnB (space group: Pnma) with high pressure and high temperature method. MnB is a promising soft magnetic material, which is ferromagnetic with Curie temperature as high as 546.3 K, and high magnetization value up to 155.5 emu/g, and comparatively low coercive field. The strong room temperature ferromagnetic properties stem from the positive exchange-correlation between manganese atoms and the large number of unpaired Mn 3d electrons. The asymptotic Vickers hardness (AVH) is 15.7 GPa which is far higher than that of traditional ferromagnetic materials. The high hardness is ascribed to the zigzag boron chains running through manganese lattice, as unraveled by X-ray photoelectron spectroscopy result and first principle calculations. This exploration opens a new class of materials with the integration of superior mechanical properties, lower cost, electrical conductivity, and fantastic soft magnetic properties which will be significant for scientific research and industrial application as advanced structural and functional materials.
High frequency stimulation induces sonic hedgehog release from hippocampal neurons
Authors: Su Yujuan , Yuan Yuan , Feng Shengjie , Ma Shaorong , Wang Yizheng 
Published: March 2017

AbstractSonic hedgehog (SHH) as a secreted protein is important for neuronal development in the central nervous system (CNS). However, the mechanism about SHH release remains largely unknown. Here, we showed that SHH was expressed mainly in the synaptic vesicles of hippocampus in both young postnatal and adult rats. High, but not low, frequency stimulation, induces SHH release from the neurons. Moreover, removal of extracellular Ca2+, application of tetrodotoxin (TTX), an inhibitor of voltage-dependent sodium channels, or downregulation of soluble n-ethylmaleimide-sensitive fusion protein attachment protein receptors (SNAREs) proteins, all blocked SHH release from the neurons in response to HFS. Our findings suggest a novel mechanism to control SHH release from the hippocampal neurons.
Engineered yeast with a CO2-fixation pathway to improve the bio-ethanol production from xylose-mixed sugars
Authors: Li Yun-Jie , Wang Miao-Miao , Chen Ya-Wei , Wang Meng , Fan Li-Hai , Tan Tian-Wei 
Published: March 2017

AbstractBio-ethanol production from lignocellulosic raw materials could serve as a sustainable potential for improving the supply of liquid fuels in face of the food-to-fuel competition and the growing energy demand. Xylose is the second abundant sugar of lignocelluloses hydrolysates, but its commercial-scale conversion to ethanol by fermentation is challenged by incomplete and inefficient utilization of xylose. Here, we use a coupled strategy of simultaneous maltose utilization and in-situ carbon dioxide (CO2) fixation to achieve efficient xylose fermentation by the engineered Saccharomyces cerevisiae. Our results showed that the introduction of CO2 as electron acceptor for nicotinamide adenine dinucleotide (NADH) oxidation increased the total ethanol productivity and yield at the expense of simultaneous maltose and xylose utilization. Our achievements present an innovative strategy using CO2 to drive and redistribute the central pathways of xylose to desirable products and demonstrate a possible breakthrough in product yield of sugars.
Androgen receptor is a potential novel prognostic marker and oncogenic target in osteosarcoma with dependence on CDK11
Authors: Liao Yunfei , Sassi Slim , Halvorsen Stefan , Feng Yong , Shen Jacson , Gao Yan , Cote Gregory , Choy Edwin , Harmon David , Mankin Henry , Hornicek Francis , Duan Zhenfeng 
Published: March 2017

AbstractOsteosarcoma is the most common bone cancer in children and adolescents. Previously, we have found that cyclin-dependent kinase 11 (CDK11) signaling was essential for osteosarcoma cell growth and survival. Subsequently, CDK11 siRNA gene targeting, expression profiling, and network reconstruction of differentially expressed genes were performed between CDK11 knock down and wild type osteosarcoma cells. Reconstructed network of the differentially expressed genes pointed to the AR as key to CDK11 signaling in osteosarcoma. CDK11 increased transcriptional activation of AR gene in osteosarcoma cell lines. AR protein was highly expressed in various osteosarcoma cell lines and patient tumor tissues. Tissue microarray analysis showed that the disease-free survival rate for patients with high-expression of AR was significantly shorter than for patients with low-expression of AR. In addition, AR gene expression knockdown via siRNA greatly inhibited cell growth and viability. Similar results were found in osteosarcoma cells treated with AR inhibitor. These findings suggest that CDK11 is involved in the regulation of AR pathway and AR can be a potential novel prognostic marker and therapeutic target for osteosarcoma treatment.