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Chinese Optics Letters 2016年第12期14卷 2-6页

作者： peter j.Winzer Nokia Bell Labs Holmdel NJ 07733 USA

This Review focuses on optical transmission fibers and the high-capacity systems operating thereon. It attempts to combine key lessons learned from the 50-year history of low-loss optical fibers with views on future fiber and systems requirements, discussing likely evolution paths and potential pitfalls in resolving the optical network capacity crunch.

关键词： multiplexing crosstalk likely resolving combine installed learned today coherent deployment

Mass Transport in Nanowire Synthesis:An Overview of Scalable Nanomanufacturing

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journal of Materials Science & Technology 2015年第6期31卷 523-532页

作者： Matthew j.Crane peter j.Pauzauskie Department of Chemical Engineering University of WashingtonSeattleWA 98195-1750.USA Department of Materials Science & Engineering Seattle.WA 98195-2120USA Fundamental Computational Science Directorate Pacific Northwest National LaboratoryRichland.WAUSA

The ability to rationally engineer the growth and nanomanufacturing of one-dimensional nanowires in high volumes has the potential to enable applications of nanoscale materials in a diverse range of fields including energy conversion and storage,catalysis,sensing,medicine,and information *** review provides a roadmap for the development of large-scale nanowire *** myriad techniques exist for bench-scale nanowire synthesis,these growth strategies typically fall within two major categories:1) anisotropically-catalyzed growth and 2) confined,template-based ***,comparisons between growth methods with different mass transport pathways have led to confusion in interpreting observations,in particular Gibbs-Thomson *** review mass transport in nanowire synthesis techniques to unify growth models and to allow for direct comparison of observations across different *** addition,we discuss the applicability of nanoscale,Gibbs-Thomson effects on mass transport and provide guidelines for the development of new growth *** explore the scalability of these complex processes with dimensionless numbers and consider the effects of pressure,temperature,and precursor material on nanowire growth.

关键词： Nanowire Mass transport Modeling Scalable growth

Medical therapy for spermatogenic failure

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Asian journal of Andrology 2012年第1期14卷 57-60,176页

作者： Ranjith Ramasamy peter j Stahl peter N Schlegel Department of Urology Weill Cornell Medical College New York NY 10065 USA

Medical treatment of men with primary spermatogenic failure remains largely ineffective in contrast to those with secondary testicular failure. Treatment has been attempted with a multitude of agents ranging from hormones to nutritional supplements （antioxidants）. While some studies have demonstrated benefit to some treatments, no treatments have consistently demonstrated efficacy nor has it been possible to reliably identify patients likely to benefit. Idiopathic spermatogenic failure likely results from multiple discrete defects in sperm production that are as yet unidentified. A better understanding of these defects will yield more effective treatment options and appropriate triage of patients to specific therapeutic regimens. This review focuses on the rationale and current evidence for hormonal and antioxidant therapy in medical treatment of male infertility, spermatogenic failure in particular. Although empiric medical therapy for spermatogenic failure has been largely replaced by assisted reproductive techniques, both treatment modalities could play a role, oerhaos as combination therapy.

关键词： antioxidant hormones male infertility sperm spermatogenesis spermatogenic failure testicular failure

Those amazing dinoflagellate chromosomes

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Cell Research 2003年第4期13卷 215-217页

作者： peter j RIZZO Department of Biology Texas A & M University College Station TX 77843 USA

Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance, because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones, dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

关键词： dinofiagellates chromosomes histones histone-like proteins.

Phase Transitions for Products of Characteristic Polynomials under Dyson Brownian Motion

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Acta Mathematica Sinica,English Series 2021年第3期37卷 509-524页

作者： peter j.FORRESTER Dang-Zheng LIU ARC Centre of Excellence for Mathematical and Statistical Frontiers School of Mathematics and StatisticsThe University of MelbourneVictoria 3010Australia CAS Key Laboratory of Wu Wen-Tsun Mathematics School of Mathematical SciencesUniversity of Science and Technology of ChinaHefei 230026P.R.China

We study the averaged products of characteristic polynomials for the Gaussian and Laguerre β-ensembles with external source, and prove Pearcey-type phase transitions for particular full rank perturbations of source. The phases are characterised by determining the explicit functional forms of the scaled limits of the averaged products of characteristic polynomials, which are given as certain multidimensional integrals, with dimension equal to the number of products.

关键词： Random matrices Dyson Brownian motion β-ensembles phase transitions

The effects of gonadal hormones on learning and memory in male mammals： A review

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Current Zoology 2011年第4期57卷 543-558页

作者： Stuart T. LEONARD peter j. WINSAUER Department of Pharmacology and Experimental Therapeutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

The primary role of the gonadal steroid hormones in mammals is to regulate reproduction and related behaviors; however, both androgens and estrogens are also integrally involved in mediating higher brain function and processes including cognition, neural development, and neural plasticity. In particular, a number of studies show that estradiol modulates dendritic spine growth and synapse density （synaptic plasticity） in the hippocampus of females, and that increased estradiol levels are generally associated with improvements on a variety of learning and memory tasks. While the majority of research has focused on the beneficial effects of estradiol in females, much less attention has been given to testosterone and its effects on learning and memory in males. Similar to estradiol titers in females, testosterone titers in males decline with age, albeit more gradually, and this decline has been correlated with impairment of certain cognitive tasks. Moreover, studies involving both humans and animals indicate that testosterone and its metabolites can augment responding on certain behavioral tasks, depending on the subject＇s current hormonal state, the response required, and the stimuli involved （e.g., those involving spatial or nonspatial stimuli）. While the exact mechanisms by which testosterone exerts its effects on learning and memory are not fully understood, recent findings suggest that testosterone modulates learning and memory in males through an interaction with the cholinergic system. The overall objective of this review is to discuss studies investigating the role of the gonadal hormones in mediating learning and memory processes in male mammals [Current Zoology 57 （4）： 543-558, 2011].

关键词： Testosterone Learning and memory Cholinergic system Mammals Cognition Androgens

Decarbonising energy: The developing international activity in hydrogen technologies and fuel cells

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journal of Energy Chemistry 2020年第12期29卷 405-415页

作者： john Meurig Thomas peter P.Edwards peter j.Dobson Gari P.Owend Department of Materials Science&Metallurgy University of CambridgeCambridge CB30FSUK King Abdulaziz City for Science and Technology(KACST)-Oxford Centre of Excellence in Petrochemicals and Inorganic Chemistry Laboratory University of OxfordOxford OX13QRUK The Queen’s College University of OxfordOxford OX14AWUK Annwvyn Solutions(Independent Consultant) BromleyKent BR13DWUK

Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy *** cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) and oxygen directly into *** hydrogen fuel cell,invented in 1839,permits the generation of electrical energy with high efficiency through a non-combustion,electrochemical process and,importantly,without the emission ofits point of ***,despite numerous efforts to exploit the obvious attractions of hydrogen technologies and hydrogen fuel cells,various challenges have been encountered,some of which are reviewed ***,however,given the exigent need to urgently seek low-carbon paths for humankind’s energy future,numerous countries are advancing the deployment of hydrogen technologies and hydrogen fuel cells not only for transport,but also as a means of the storage of excess renewable energy from,for example,wind and solar ***,hydrogen is also being blended into the natural gas supplies used in domestic heating and targeted in the decarbonisation of critical,large-scale industrial processes such as steel *** briefly review specific examples in countries such as japan,South Korea and the People’s Republic of China,as well as selected examples from Europe and North America in the utilization of hydrogen technologies and hydrogen fuel cells.

关键词： Decarbonisation Hydrogen Energy Hydrogen Economy Fuel cells Environment Sustainability

Polyelectrolyte multilayer electrostatic gating of graphene field-effect transistors

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Nano Research 2014年第11期7卷 1650-1658页

作者： Yung Yu Wang peter j. Burke Department of Chemical Engineering and Materials Science University of California Irvine Irvine California 92697 USA Department of Electrical Engineering and Computer Science University of California Irvine Irvine California 92697 USA

We apply polyelectrolyte multilayer films by consecutive alternate adsorption of positively charged polyallylamine hydrochloride and negatively charged sodium polystyrene sulfonate to the surface of graphene field effect transistors. Oscillations in the Dirac voltage shift with alternating positive and negative layers clearly demonstrate the electrostatic gating effect in this simple model system. A simple electrostatic model accounts well for the sign and magnitude of the Dirac voltage shift. Using this system, we are able to create p-type or n-type graphene at will. This model serves as the basis for understanding the mechanism of charged polymer sensing using graphene devices, a potentially technologically important application of graphene in areas such as DNA sequencing, biomarker assays for cancer detection, and other protein sensing applications.

关键词： dirac point graphene transistor electrostatic gating polyallylaminehydrochloride (PAH) sodium polystyrenesulfonate (PSS)

Characterization of multi-GNSS between-receiver differential code biases using zero and short baselines

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Science Bulletin 2015年第21期60卷 1840-1849页

作者： Baocheng Zhang peter j.G.Teunissen Global Navigation Satellite System (GNSS) Research Centre Curtin University Geoscience and Remote Sensing Delft University of Technology

Care should be taken to minimize adverse impact of receiver differential code biases(DCBs) on global navigation satellite system(GNSS)-derived ionospheric parameters. It is therefore of importance to ascertain the intrinsic characteristics of receiver DCBs,preferably in the context of new-generation GNSS. In this contribution, we present a method that enables time-wise retrieval of between-receiver DCBs(BR-DCBs) from dualfrequency, code-only measurements collected by a pair of co-located receivers. This method is applicable to the US GPS as well as to a new set of GNSS constellations including the Chinese Bei Dou, the European Galileo and the japanese QZSS. With the use of this method, we determine the multi-GNSS BR-DCB time-wise estimates covering a time period of up to 2 years(january 2013–March 2015) with a 30-s time resolution for five receiverpairs(four zero and one short baselines). For the BR-DCB time-wise estimates pertaining to an arbitrary receiver-pair and constellation, we demonstrate their promising intraday stability by means of statistical hypothesis testing. We also find that the Bei Dou BR-DCB daily weighted average(DWA) estimates show a dependence on satellite type, in particular for receiver-pairs of mixed types. Finally, we demonstrate that long-term variability in BR-DCB DWA estimates can be closely associated with hardware temperature variations inside the receivers.

关键词： Global navigation satellite system(GNSS) Total electron content (TEC) Between-receiver differential code bias (BR-DCB) BeiDoucode inter-satellite-type-bias (ISTB)