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Unbiased Diffusion to Escape Complex Geometries: Is Reduction to Effective One-Dimensional Description Adequate to Assess Narrow Escape Times?

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Applied mathematics 2014年第8期5卷 1218-1225页

作者： Yoshua Chávez Guillermo Chacón-Acosta marco-vinicio vázquez Leonardo Dagdug Applied mathematics and Systems Department Universidad Autónoma Metropolitana-Cuajimalpa México DF México Chemistry Department Universidad Autónoma Metropolitana-Iztapalapa México DF México Physics Department Universidad Autónoma Metropolitana-Iztapalapa México DF México

This study is devoted to unbiased diffusion of point Brownian particles inside a tube of varying cross-section (see Figure 1). An expression for the mean survival time, , of the particles inside the tube is obtained in terms of the bulk diffusion constant, D0 and the system’s geometrical parameters, namely, the tube’s axial semi-length, L, the minor radius, , and the slope of the tube’s wall, . Our expression for correctly retrieves the limit behavior of the system under several conditions. We ran monte Carlo numerical simulations to compute the mean survival time by averaging the survival time of 5 × 104 trajectories, with time step t = 10-6, D0 = 1, and L = 1. The simulations show good agreement with our model. When the geometrical parameters of this system are varied while keeping constant the tube’s enclosed volume, it resembles the problems of Narrow Escape Time (J. Chem. Phys. 116(22), 9574 (2007)). A previous study on the use of the reduction to effective one-dimension technique (J. mod. Phys. 2, 284 (2011)) in complex geometries has shown excellent agreement between the theoretical model and numerical simulations. However, in this particular system, the general assumptions of the Hill problem are seemingly inapplicable. The expression obtained shows good agreement with our simulations when 0 ≤ ≤ 1, but fails when grows larger. On the other hand, some errors are found when 0, but the expression holds reasonably well for a broad range of values of . These comparisons between simulations and theoretical predictions, and the expressions obtained for , are the main results of this work.

关键词： Component Formatting Style Styling Insert

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RANK-ligand and osteoprotegerin as biomarkers in the differentiation between periprosthetic joint infection and aseptic prosthesis loosening

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World Journal of Orthopedics 2017年第4期8卷 342-349页

作者： max J Friedrich matthias D Wimmer Jan Schmolders Andreas C Strauss milena m Ploeger Hendrik Kohlhof Dieter C Wirtz Sascha Gravius Thomas m Randau Department of Orthopedics and Trauma Surgery University Clinic of Bonn

AIm To assess serum levels of RANK-ligand(RANKL) and osteoprotegerin(OPG) as biomarkers for periprosthetic joint infection(PJI) and compare their accuracy with standard *** One hundred and twenty patients presenting with a painful total knee or hip arthroplasty with indication for surgical revision were included in this prospective clinical trial. Based on standard diagnostics(joint aspirate, microbiological, and histological samples) and musculoskeletal Infection Society consensus classification,patients were categorized into PJI, aseptic loosening,and control groups. Implant loosening was assessed radiographically and intraoperatively. Preoperative serum samples were collected and analyzed for RANKL, OPG, calcium, phosphate, alkaline phosphatase(AP), and the bone-specific subform of AP(b AP). Statistical analysis was carried out, testing for significant differences between the three groups and between stable and loose implants. RESULTS All three groups were identical in regards to age, gender, and joint distribution. No statistically significant differences in the serum concentration of RANKL(P = 0.16) and OPG(P = 0.45) were found between aseptic loosening and PJI, with a trend towards lower RANKL concentrations and higher OPG concentrations in the PJI group. The RANKL/OPG ratio was significant for the comparison between PJI and non-PJI(P = 0.005). A ratio > 60 ruled out PJI in all cases(specificity: 100%, 95%CI: 89, 11% to 100.0%) but only 30% of non-PJI patients crossed this threshold. The positive predictive value remained poor at any cut-off. In the differentiation between stable and loose implants, none of the parameters measured(calcium, phosphate, AP, and b AP) showed a significant difference, and only AP and b AP measurements showed a tendency towards higher values in the loosened group(with P = 0.09 for AP and P = 0.19 for b AP). CONCLUSION Lower RANKL and higher OPG concentrations could be detected in PJI, without statistical significance.

关键词： Aseptic loosening Diagnostic RANK-ligand Periprosthetic joint infection Biomarker Osteoprotegerin

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Investigation of Li-ion transport in Li7P3S11 and solid-state lithium batteries

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Journal of Energy Chemistry 2019年第11期28卷 1-7页

作者： Chuang Yu Swapna Ganapathy Ernst R.H.van Eck Lambert van Eijck Niek de Klerk Erik m.Kelder marnix Wagemaker Department of Radiation Science and Technology Delft University of TechnologyMekelweg 152629JB Delftthe Netherlands Institute for molecules and materials Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands

The high Li-ion conductivity of the Li7P3S11 sulfide-based solid electrolyte makes it a promising candidate for all-solid-state lithium batteries. The Li-ion transport over electrode-electrolyte and electrolyteelectrolyte interfaces, vital for the performance of solid-state batteries, is investigated by impedance spectroscopy and solid-state NmR experiments. An all-solid-state Li-ion battery is assembled with the Li7P3S11 electrolyte, nano-Li2S cathode and Li-In foil anode, showing a relatively large initial discharge capacity of 1139.5 m Ah/g at a current density of 0.064 m A/cm^ 2 retaining 850.0 m Ah/g after 30 cycles. Electrochemical impedance spectroscopy suggests that the decrease in capacity over cycling is due to the increased interfacial resistance between the electrode and the electrolyte. 1D exchange ^7Li NmR quantifies the interfacial Li-ion transport between the uncycled electrode and the electrolyte, resulting in a diffusion coefficient of 1.70(3) ×10^-14cm^2/s at 333 K and an energy barrier of 0.132 e v for the Li-ion transport between Li2S cathode and Li7P3S11 electrolyte. This indicates that the barrier for Li-ion transport over the electrode-electrolyte interface is small. However, the small diffusion coefficient for Li-ion diffusion between the Li2S and the Li7P3S11 suggests that these contact interfaces between electrode and electrolyte are relatively scarce, challenging the performance of these solid-state batteries.

关键词： Li7P3S11 Li-ion transport Spin-lattice NmR Exchange NmR Solid-state battery

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Enhancing sensitivity to ambient refractive index with tunable few-layer graphene/hBN nanoribbons

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Photonics Research 2019年第7期7卷 130-137页

作者： Huan Jiang Sajid Choudhury Zhaxylyk A.Kudyshev Di Wang Ludmila J.Prokopeva Peng Xiao Yongyuan Jiang Alexander v.Kildishev Institute of modern Optics Department of PhysicsHarbin Institute of TechnologyHarbin 150001China School of Electrical and Computer Engineering and Birck Nanotechnology Center Purdue UniversityWest Lafayette Indiana 47907USA School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Key Laboratory of micro-Optics and Photonic Technology of Heilongjiang Province Harbin 150001China Key Laboratory of micro-Nano Optoelectronic Information System of ministry of Industry and Information Technology Harbin 150001China

Refractive index (RI) sensing helps to identify biomolecules and chemicals in the mid-infrared range for drug discovery, bioengineering, and environmental monitoring. In this paper, we numerically demonstrate an electrically tunable RI sensor with ultrahigh sensitivity using a three-layer graphene nanoribbon array separated by hexagonal boron nitride (hBN). Unlike the weak resonance in single-layer graphene nanoribbons, a much stronger plasmon resonance featuring a higher-quality factor can be excited in the graphene/hBN few-layer ribbon array. Simultaneously, the high purity of graphene on hBN results in an outstanding charge mobility above 4 ×10^4 cm^2 · v^-1·s^-1 at 300 K, which allows a larger modulation depth. The interaction between the locally enhanced field around graphene ribbons and its surrounding analyte leads to ultrahigh sensitivity (4.207μm/RIU), with the figure of merit reaching approximately ***, this ultrasensitive detector could selectively work in different wavebands by controlling gate voltages applied to *** merits of ultrahigh sensitivity and electrical tunability are major advances compared to previous RI sensors, paving a way toward ultrasensitive detection using graphene/hBN few-layer devices.

关键词： Enhancing sensitivity refractive index nanoribbons

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STUDY OF WASTE FROm THE ABAKAN THERmAL POWER PLANT WITH THE PURPOSE OF ITS POSSIBLE USE IN CEmENTLESS CONCRETE

STUDY OF WASTE FROM THE ABAKAN THERMAL POWER PLANT WITH THE ...

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第四届北京国际水泥与混凝土会议

作者： S. Pavlenko Yu. Bazhenov v.malyshkin Siberian State Academy of mining & metallurgy. Nowokuznetsk RUSSIA654007

Creation of fine cementless ash-slag concrete based on high-calcium ash and slag from thermal power plants is the part of a Federal programme of Environment Protection. Long-term investigations into physical properties, chemical analysis, silicate and ferriferous decomposition, radionuclides contents of fly ash and slag from the Abakan thermal power plant were performed. The results were compared with up-to-date State Standards (25818-91, 26844-85) and Specification (39-70.10898-88). Deviation from the requirements of the State Standards and Specification were revealed, methods of treatment of ash (grinding to the fineness of 450m2/kg) and slag (grinding to sand with a particle size of 0 to 5 mm) as well as technique for producing high-performance cementless concrete (introduction of microsilica, double heat treatment) were suggested. The work underwent the examination by the NIIZhB and moscow State University of Construction and was patented (Patent N 2065420. Concrete mixture). The project for by Committee for Nature Preservation, Khakass Republic, was developed.

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金属碲化物[Ga(en)_3]In_3Te_7晶体结构和性质的研究

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化学学报 2000年第7期58卷 835-839页

作者：陈震 D.m.Proserpio 黄子祥福建师范大学实验中心 Department of Chemistry Rutgers UniversityCamdenNJ.08102USA 中国科学院福建物质结构研究所

以有机溶剂热生长技术(solvothermal technique),即在180℃乙二胺(en)溶液中,以GaCl_3,InCl_3,Rb_2Te和Te在密闭容器中反应7d,制备出新的硫族化合物[Ga(en)_3]In_3Te_7.其阴离子基团为Zintl anion:_∞~2[In_3Te_7]^(3-),阳离子基因为Ga与乙二胺(en)的配合物:[Ga(en)_3]^(3+).以单晶X射线衍射技术解得该晶体结构属单钭晶系,空间群为P2_1/c,(no.14),[Ga(en)_3]In_3Te_7的晶胞数据:a=1.0460(2)nm,b=1.6981(3)nm,c=1.4994(6)nm,α=90°,β=95.46(2)°,γ=90°,v=2.651(1)nm^3,Z=4.热分析结果表明,该化合物的热分解分三步进行.光学性质测试表明它们是半导体材料,禁带宽度为1.65ev.

关键词：晶体结构有机溶剂热生长技术金属碲化物

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Effect of 17β-estradiol on the Brain Damage and metabolic Changes in Rats

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Journal of Huazhong University of Science and Technology(medical Sciences) 2001年第1期21卷 62-64,74页

作者： CHEN Jincao Department of Neurosurgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Neurosurgical Laboratory University Hospital Basel Basel Switzerland

An in vivo model of glutamate excitotoxicity in which glutamate is applied to the cortex of rats through a microdialysis probe has been used to investigate the neuroprotective processes initiated by 17β estradiol. Rats were pre treated with 17β estradiol i.v. before local application of glutamate. The experimental results showed that pre treatment with 17β estradiol significantly reduced the size of the glutamate induced lesion. In the microdialysates, the peak of lactate observed immediately after glutamate application was significantly higher and longer lasting after 17β estradiol pre treatment. The level of extracellular glucose was markedly decreased concomitantly to the increase in lactate, but no difference could be observed with and without 17β estradiol pre treatment. These suggest a new neuroprotective mechanism of 17β estradiol by activating glutamate induced lactate production. This effect on lactate production and lesion reduction is estrogen receptor dependent and is abolished totally by estrogen antagonist tamoxifen. It was also demonstrated here that high lactate subserves estrogen neuroprotection during glutamate toxicity.

关键词： estradiol glutamate excitotoxicity in vivo microdialysis lactate neuroprotection

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The effectiveness of post-procedure criteria for discharge following outpatient percutaneous nephrostomy

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介入放射学杂志 1995年第3期 182-183页

作者： J.J.Snidow v.J.Harris K.K.Kopecky m.S.Johnson S.O.Trerotola Indiana University medical Center,Department of Diagnostic Imaging,vascular/Interventional Radiology Section Indianapolis,USA

Purpose:to evaluate the effectiveness of post-procedure discharge criteria by assessing the incidence of procedure complications that require delayed hospitalization follow-ing discharge of outpatients undergoing percutaneous *** and methods:the criteria used for outpatient discharge following percutaneousnephrostomy were the abvsence of shaking chilis,hypotension,uncontgrolled hypertension,and syspnoea in an alert and cooperative patient who was accompanied by motivated and ca-pable home czarfe ***-up consisted of direct discussion with referring physi-cians,and review of medical charts,imaging films,and image-guided procedure reports forall(n=23)outpatients who were discharged home following percutaneous nephrostomy atour institution between July 1991 and June *** initial 17 patients were evaluatedregtrospectively whereas the last 6 patients were followed *** age rangedfrom 20 to 77 years with a mean of *** with benign disease(n=12)and malignancy(n=11)were *** spectrum of procedure complexity ranged from external percurta-neous nephrostomy(n=15)to external nephroureterostomy(n=7)and internalnephroureteral stent placement(n=1)with tube size ranging from 8 to 12 *** patientshad coagulopathy but five patients had infected urine at the time of the *** of the outpatients who were discharged after meeting post-procedure criteriadied as a result of procedure complications or required later hospital admission for observationor treatment of peri-procedure ***:the results suggest that the post-procedure discharge criteria described hereinare effective in maintaining the safety of the outpatient percutaneous nephrostomy process.

关键词： outpatient hypotension malignancy admission discharged stent alert maintaining shaking motivated

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Parallel arrays of Schottky barrier nanowire field effect transistors： Nanoscopic effects for macroscopic current output

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Nano Research 2013年第6期6卷 381-388页

作者： Sebastian Pregl Walter m. Weber Daijiro Nozaki Jens Kunstmann Larysa Baraban Joerg Opitz Thomas mikolajick Gianaurelio Cuniberti Institute for materials Science and max Bergmann Center of Biomaterials TU Dresden Dresden 01062 Germany NamLab GmbH Dresden 01187 Germany Fraunhofer Institute IZFP Dresden Dresden 01109 Germany Institute for Semiconductors and microsystems Technology TU Dresden Dresden 01187 Germany Division of IT Convergence Engineering POSTECH Pohang Korea

We present novel Schottky barrier field effect transistors consisting of a parallel array of bottom-up grown silicon nanowires that are able to deliver high current outputs. Axial silicidation of the nanowires is used to create defined Schottky junctions leading to on/off current ratios of up to 106. The device concept leverages the unique transport properties of nanoscale junctions to boost device performance for macroscopic applications. Using parallel arrays, on-currents of over 500 gA at a source-drain voltage of 0.5 v can be achieved. The transconductance is thus increased significantly while maintaining the transfer characteristics of single nanowire devices. By incorporating several hundred nanowires into the parallel arra36 the yield of functioning transistors is dramatically increased and device- to-device variability is reduced compared to single devices. This new nanowire- based platform provides sufficient current output to be employed as a transducer for biosensors or a driving stage for organic light-emitting diodes （LEDs）, while the bottom-up nature of the fabrication procedure means it can provide building blocks for novel printable electronic devices.

关键词： silicon nanowire effective Schottky barrier lowering parallel arra^electric field enhancement output current amplification

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Dispersal behavior of yellowjacket （vespula germanica） queens

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Insect Science 2018年第1期25卷 109-116页

作者： maite masciocchi Andres S. martinez Aria J. Pereira Jose m. villacide Juan C. Corley CONICET CCT Comahue INTA Grupo de Ecologia de Poblaciones de Insectos INTA EEA Bariloche Argentina Centro Regional Universitario Bariloche U. N. del Comahue Bariloche 8400 Argentina

Understanding the factors that affect animal dispersal behavior is important from both *** and applied perspectives. Dispersal can have clear evolutionary and ecological consequences, but for normative insect pests, dispersal capacity can also help to explain invasion success. vespula germanica is a social wasp that, in the last century, has successfully invaded several regions of the world, showing one of the highest spread rates reported for a nonnative insect. In contrast with nonsocial wasps, in social species, queens are responsible for population redistribution and spread, as workers are sterile. For v. germanica, it has been observed that queen flight is limited to 2 distinct periods： early autumn, when new queens leave the nest to mate and find sheltered places in which to hibernate, and spring when new colonies are founded. Our aim was to study the flight behavior of v. germanica queens by focusing on the different periods in which dispersal occurs, characterizing as well the potential contribution of queen flight （i.e., distance） to the observed geographical spread. Our results suggest that the distances flown by nonover- wintered queens is greater than that flown by overwintered individuals, suggesting that the main queen dispersal events would occur before queens enter hibernation. This could relate to a behavioral trait of the queens to avoid the inbreeding with related drones. Additionally, given the short distances flown and remarkable geographical spread observed, we provide evidence showing that queen dispersal by flight is likely to contribute proportionately less to population spread than human-aided factors.

关键词： flight potential German wasps hibernation invasive wasps social insect

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