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Nano Research 2020年第5期13卷 1465-1471页

作者： Thomas A.Celano Seokhyoung Kim david j.Hill james F.Cahoon Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599-3290USA

Bottom-up synthesis of semiconductor nanowires(NWs)by the vapor-liquid-solid(VLS)mechanism has enabled diverse technological applications for these *** metallic NWs,however,it has been challenging to form large-area interconnected NW ***,we generate centimeter-scale meshes of mechanically and electrically interconnected Si NWs by sequentially growing,collapsing,and joining the NWs using a capillarity-driven welding *** fabricate meshes from VLS-grown NWs ranging in diameter from 20 to 100 nm and find that the meshes are three-dimensional with a thickness ranging from^1 to^10 microns depending on the NW *** extinction measurements reveal that the networks are semi-transparent with a color that depends on the absorption and scattering characteristics of individual ***,active voltage contrast imaging of both centimeter-and micron-scale meshes reveals widespread electrical *** a sacrificial layer,we demonstrate that the mesh can be liberated from the growth substrate,yielding a highly flexible and transparent *** transport measurements both on the growth substrate and on liberated,flexible films reveal electrical conduction across a centimeter scale with a sheet resistance of^160-180 kΩ/square that does not change significantly upon *** the ability to encode complex functionality in semiconductor NWs through the VLS process,we believe these meshes of networked NWs could find application as neuromorphic memory,electrode scaffolds,and bioelectronic interfaces.

关键词： semiconductor nanowire conductive network flexible electronics welding thermal annealing active-voltage contrast

Foreword to Semen Analysis in 21st Century Medicine special issue in Asian journal of Andrology

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Asian journal of Andrology 2010年第1期12卷 7-10页

作者： david j. Handelsman Trevor G. Cooper Reproductive Endocrinology ＆ Andrology ANZA C Research Institute Sydney Australia Andrology Laboratory Institute of Reproductive Medicine of the University Munster Germany

Semen analysis as an integral part of infertility investigations has a surprisingly long history, emerging only slowly, from under a cloud of disrepute and occupying a solitary niche outside conventional pathology tests, until relatively recently. From origins in the 19th century when spermatozoa were only identified as present or absent in cervical mucus samples from postcoital tests, even then a practice deemed ＂... dabbling incompatible with decency and self-respect...＂（cited in [1]）.

关键词： no english key word

Annealing Response of Cold-Rolled Vanadium Microalloyed Sheet Steels

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journal of Iron and Steel Research International 2011年第S1期18卷 404-411页

作者： john G Speer david K Matlock Robert j Glodowski A dvanced Steel Processing and Products Research Center Colorado School of MinesGoldenColorado USA East Metals (North America) LLCPittsburghPAUSA

Vanadium microalloying is widely employed in hot-rolled HSLA products;because of its relatively high solubility in austenite,vanadium plays a special role in thin-slab cast hot-rolled products where reheating is limited prior to *** cold-rolled and annealed sheet steels,vanadium technology has been employed in bake-hardenable drawing-quality steels,and in HSLA *** studies have investigated the continuous and batch annealing response of vanadium-containing cold-rolled HSLA steels,with an emphasis on aluminum and nitrogen variations (because of the special importance of nitrogen in vanadium microallyed steels,and interesting interactions between vanadium,aluminum and nitrogen).The present contribution reviews some key aspects of vanadium-microalloyed coldrolled sheet steels,and highlights the results of selected studies showing the influence of steel composition and processing.

关键词： Microalloying vanadium,bake-hardening cold rolled sheet steel

High–Speed electron beam curing of thick electrode for high energy density Li-ion batteries

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Green Energy & Environment 2019年第4期4卷 375-381页

作者： Zhijia Du Christopher j.janke jianlin Li david L.Wood III Energy and Transportation Science Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Chemical Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

Electron beam curing is demonstrated as a promising method for high speed,low cost and environmentally friendly battery electrode *** work reports transfer of this process to pilot scale equipment and evaluation of electrochemical performance in prototype 1.5 Ah pouch *** LiNi0.5Mn0.3Co0.2O2(NMC532)composite electrodes with an areal loading of 25 mg cm^-2(~4 mAh cm^-2)are successfully cured at a line speed of 500 feet per minute at 275 *** to the NMC532 cathode processed via a conventional coating method,the electron beam cured electrodes show higher capacity fade in the first 100 cycles,but similar fade rate *** improvement strategies are proposed and *** work demonstrates that electron beam curing is a promising method for manufacturing thick battery electrodes at high speeds and low capital/operation cost.

关键词： Electron beam curing Li-ion batteries Thick electrode

Abscisic Acid Receptors:Past,Present and Future

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journal of Integrative Plant Biology 2011年第6期53卷 469-479页

作者： jianjun Guo Xiaohan Yang david j. Weston jin-Gui Chen Department of Genetics Harvard Medical School Boston Massachusetts 02114-2790 USA Department of Molecular Biology Massachusetts General Hospital Boston Massachusetts 02114-2790 USA Biosciences Division Oak Ridge National Laboratory Oak Ridge TN 37831-6422 USA

acid （ABA） is the key plant stress hormone. Consistent with the earlier studies in support of the presence of both membrane- and cytoplasm-localized ABA receptors, recent studies have identified multi- ple ABA receptors located in various subcellular locations. These include a chloroplast envelope-localized receptor （the H subunit of Chloro- plast Mg2＋-chelatase/ABA Receptor）, two plasma membrane-localized receptors （G-protein Coupled Receptor 2 and GPCR-type G proteins）, and one cytosol/nucleus-localized Pyrabactin Resistant （PYR）/PYR-Like （PYL）/Regulatory Component of ABA Receptor 1 （RCAR）. Although the downstream molecular events for most of the identified ABA receptors are currently unknown, one of them, PYR/PYL/RCAR was found to directly bind and regulate the activity of a long-known central regulator of ABA signaling, the A-group protein phosphatase 2C （PP2C）. Together with the Sucrose Non-fermentation Kinase Subfamily 2 （SnRK2s） protein kinases, a central signaling complex （ABA-PYR-PP2Cs-SnRK2s） that is responsible for ABA signal perception and transduction is supported by abundant genetic, physiological, biochemical and structural evidence. The identification of multiple ABA receptors has advanced our understanding of ABA signal perception and transduction while adding an extra layer of complexity.

关键词： ABA ChlH/ABAPjCCH/GUN5 FCA GCR2 GTGIlGTG2 PYLIPYL/RCAR.

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Multidisciplinary perspectives on mechanisms of activity of popular immune-enhancing herbal supplements used by athletes

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Frontiers in Biology 2013年第1期8卷 78-100页

作者： david S. SENCHINA justus E. HALLAM david j. CHENEY Department of Biology Drake University Des Moines IA 50311 USA Department of Kinesiology Iowa State-University Ames IA 50011 USA Mayo Clinic Rochester MN 55905 USA

This paper examines cellular and molecular mechanisms that may underpin the purported effects of five herbal supplements in the context of athlete immune function. Ginseng and echinacea are used frequently by athletes, whereas astragalus and elderberry are used infrequently and pequi is just emerging as a possible supplement. In vivo studies of these products on athlete immune function have yielded heterogeneous results, likely due to experimental design differences. Ginseng, echinacea, elderberry, and pequi are considered asterids sensu lato. Ginseng appears to exert strongest effects on components of adaptive immunity, in particular maintaining Thl/Th2 balance of CD4^4 T cells and their downstream effects, via its ginsenosides, flavonoids, and polysaccharides. Echinacea alkamides, caffeic acid derivatives, and polysacchardies may target both innate and adaptive immunity, though perhaps the former more consistently. Elderberry harbors anthocyanins and lectins which may modulate innate immunity. Data on pequi is limited but suggests that carotenoids, phenols, and fatty acids may alter circulating leukocyte populations. More phylogenetically distant, astragalus is a rosid sensu lato and may influence the innate immune system through flavonoids, polysaccharides, and saponins. Supplements generally demonstrate no effects on physiologic parameters such as lactate, oxygen dynamics, or athletic performance. Bioavailability studies indicate that purported bioactive molecules of these supplements may reach circulation in low but therapeutically-relevant quantities. Difficulties in cross- comparisons due to study design differences, coupled with an overall dearth of research on the topic, currently hamper any formal conclusions regarding the efficacy of these supplements as immunoregulators for athletes.

关键词： athlete dietary supplement exercise herb immunity mechanism

A fine-scale assessment of the ecosystem service-disservice dichotomy in the context of urban ecosystems affected by alien plant invasions

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Forest Ecosystems 2019年第4期6卷 323-338页

作者： Luke j.Potgieter Mirijam Gaertner Patrick j.O’Farrell david M.Richardson Centre for Invasion Biology Department of Botany and ZoologyStellenbosch University

Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) are an important response. Given the limited resources available for assessing urban ES in many cities, practical approaches for integrating ES in decision-making process are ***: We apply remote sensing techniques(integrating LiDAR data with high-resolution multispectral imagery)and combined these with supplementary spatial data to develop a replicable approach for assessing the role of urban vegetation(including invasive alien plants) in providing ES and ecosystem disservices(EDS). We identify areas denoting potential management trade-offs based on the spatial distribution of ES and EDS using a local-scale case study in the city of Cape Town, South Africa. Situated within a global biodiversity hotspot, Cape Town must contend with widespread invasions of alien plants(especially trees and shrubs) along with complex socio-political challenges. This represents a useful system to examine the challenges in managing ES and EDS in the context of urban plant ***: Areas of high ES provision(for example carbon sequestration, shade and visual amenity) are characterized by the presence of large trees. However, many of these areas also result in numerous EDS due to invasions of alien trees and shrubs – particularly along rivers, in wetlands and along the urban edge where tall alien trees have established and spread into the natural vegetation(for example increased water consumption, increased fire risk and reduced soil quality). This suggests significant trade-offs regarding the management of species and the ES and EDS they ***: The approach applied here can be used to provide recommendations and to guide city planners and managers to fine-tune management interventions at local scales to maximise the provision of ES.

关键词： Biodiversity Biological invasions Ecosystem disservices Ecosystem services Remote sensing Trade-offs Tree invasions Urban plant invasions

A classification of genes involved in normal and delayed male puberty

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Asian journal of Andrology 2023年第2期25卷 230-239页

作者： Maleeha Akram Syed Shakeel Raza Rizvi Mazhar Qayyum david j Handelsman Department of Zoology Wildlife and FisheriesPir Mehr Ali Shah Arid Agriculture University RawalpindiShamsabadMurree RoadRawalpindi 46300Pakistan Andrology Laboratory The ANZAC Research InstituteHospital RoadConcordNSW 2139Australia

Puberty is a pivotal biological process that completes sexual maturation to achieve full reproductive *** is a major transformational period of life,whose timing is strongly affected by genetic makeup of the individual,along with various internal and external *** the exact mechanism for initiation of the cascade of molecular events that culminate in puberty is not yet known,the process of pubertal onset involves interaction of numerous complex signaling pathways of hypothalamopituitary-testicular(HPT)*** developed a classification of the mechanisms involved in male puberty that allowed placing many genes into physiological *** include(i)hypothalamic development during embryogenesis,(ii)synaptogenesis where gonadotropin releasing hormone(GnRH)neurons form neuronal connections with suprahypothalamic neurons,(iii)maintenance of neuron homeostasis,(iv)regulation of synthesis and secretion of GnRH,(v)appropriate receptors/proteins on neurons governing GnRH production and release,(vi)signaling molecules activated by the receptors,(vii)the synthesis and release of GnRH,(viii)the production and release of gonadotropins,(ix)testicular development,(x)synthesis and release of steroid hormones from testes,and(xi)the action of steroid hormones in downstream effector *** in components of this system during embryonic development,childhood/adolescence,or adulthood may disrupt/nullify puberty,leading to long-term male infertility and/or *** review provides a list of 598 genes involved in the development of HPT axis and classified according to this ***,this review identifies a subset of 75 genes for which genetic mutations are reported to delay or disrupt male puberty.

关键词： delayed puberty gonadotropin releasing hormone hypogonadism male puberty puberty testosterone

Strengthening an in-service reinforcement concrete bridge with prestressed CFRP bars

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 635-644页

作者： Hai-long WANG Wei-liang jIN david j. CLELAND Ai-hui ZHANG Department of Civil Engineering Zhejiang University Hangzhou 310027 China School of Planning Architecture and Civil Engineering Queen's University Belfast Belfast BT9 5AG UK

Carbon fiber reinforced polymer (CFRP) bars were prestressed for the structural strengthening of 8 T-shaped rein-forced concrete (RC) beams of a 21-year-old bridge in China. The ultimate bearing capacity of the existing bridge after retrofit was discussed on the basis of concrete structures theory. The flexural strengths of RC beams strengthened with CFRP bars were controlled by the failure of concrete in compression and a prestressing method was applied in the retrofit. The field construction processes of strengthening with CFRP bars-including grouting cracks, cutting groove, grouting epoxy and embedding CFRP bars, surface treating, banding with the U-type CFRP sheets, releasing external prestressed steel tendons-were introduced in detail. In order to evaluate the effectiveness of this strengthening method, field tests using vehicles as live load were applied before and after the retrofit. The test results of deflection and concrete strain of the T-shaped beams with and without strengthening show that the capacity of the repaired bridge, including the bending strength and stiffness, is enhanced. The measurements of crack width also indicate that this strengthening method can enhance the durability of bridges. Therefore, the proposed strengthening technology is feasible and effective.

关键词： Carbon fiber reinforced polymer (CFRP) bar Reinforced concrete (RC) bridge Strengthening Construction pro-cedure Field test T-shaped beam