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Proton-pump inhibitor use does not affect semen luality in subfertile men

Asian Journal of Andrology 2018年第3期20卷 290-293页

作者： Sorena Keihani James R Craig Chong Zhang Angela P Presson Jeremy b Myers William O brant Kenneth I Aston benjamin R Emery Timothy G Jenkins douglas T Carrell James M Hotaling Division of Urology Department of Surgery University of Utah Salt Lake City Utah 84132 USA Division of Epidemiology Department of Internal Medicine University of Utah Salt Lake City Utah 84132 USA Andrology and IVF Laboratory Department of Surgery (Urology) University of Utah Salt Lake City Utah 84108 USA

Proton-pump inhibitors （PPIs） are among the most widely used drugs worldwide. PPI use has recently been linked to adverse changes in semen quality in healthy men; however, the effects of PPI use on semen parameters remain largely unknown specifically in cases with male factor infertility. We examined whether PPI use was associated with detrimental effects on semen parameters in a large population of subfertile men. We retrospectively reviewed data from 12 257 subfertile men who had visited our fertility clinic from 2003 to 2013. Patients who reported using any PPIs for 〉3 months before semen sample collection were included; 7698 subfertile men taking no medication served as controls. Data were gathered on patient age, medication use, and conventional semen parameters; patients taking any known spermatotoxic medication were excluded. Linear mixed-effect regression models were used to test the effect of PPI use on semen parameters adjusting for age. A total of 248 patients （258 samples） used PPIs for at least 3 months before semen collection. In regression models, PPI use （either as the only medication or when used in combination with other nonspermatotoxic medications） was not associated with statistically significant changes in semen parameters. To our knowledge, this is the largest study to compare PPI use with semen parameters in subfertile men. Using PPIs was not associated with detrimental effects on semen quality in this retrospective study.

关键词： infertility proton-pump inhibitors semen analysis sperm quality spermatozoa

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Vortex-Wave Interaction on a Sphere

Vortex-Wave Interaction on a Sphere

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The Fifth International Conference on Fluid Mechanics

作者： R.b.nelson N.R.McDonald Department of Mathematics University College London

＜正＞The interaction of a point vortex with a single vorticity jump separating regions of opposite signed vorticity on the surface of a sphere is *** small amplitude interfacial waves are considered where linear theory is applicable.A point vortex in a region of same signed vorticity will initially move away from the interface and a point vortex in a region of opposite signed vortex will move towards *** with weak vortices sufficiently far from the interface then undergo meridional oscillation whilst precessing about the sphere.A vortex at a pole in a region of same sign vorticity is a stable equilibrium where as the other case is an unstable *** computations using contour dynamics confirm these results and nonlinear cases are examined.

关键词： point vortex vortex motion contour dynamics interface

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Patterns of host cell inheritance in the bacterial symbiosis of whiteflies

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Insect Science 2020年第5期27卷 938-946页

作者： Xiao-Rui Xu Na-Na Li Xi-Yu bao Angela E.douglas Jun-bo Luan Liaoning Key Laboratory of Economic and Applied Entomology College of Plant ProtectionShenyang Agricutural UniversityShenyangChina Department of Entomology Cornell UniversitIthacaNYUSA Department of Molecular biology and Genetics Cormell UniversitylthacaNYUSA

Whiteflies possess bacterial symbionts Candidatus Portiera aleyrodidium that are housed in specialized cells called bacteriocytes and are faithfully transmitted via the ovary to insect *** one whitefly species studied previously,bemisia tabaci MEAMI,transmission is mediated by somatic inheritance of bacteriocytes,with a single bacteriocyte transferred to each oocyte and persisting through embryogenesis to the next ***,we investigate the mode of bacteriocyte transmission in two whiefly species,*** MED,the sister species of MEAM1,and the phylogenetically distant species Trialeurodes *** analysis supported by microscopical studies demonstrates that *** MED bacteriocytes are genetically different from other somatic cells and persist through embryogenesis,as for MEAMI,but *** bacteriocytes are genetically identical to other somatic cells of the insect,likely mediated by the degradation of maternal bacteriocytes in the *** two alternative modes of transmission provide a first demonstration among insect symbioses that the cellular processes underlying vertical transmission of bacterial symbionts can diversify among related host species associated with a single lineage of symbiotic bacteria.

关键词： bacteriocyte inheritance somatic cells symbiont transmission whitefly

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Five Colletotrichum species are responsible for mango anthracnose in northeastern brazil

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Fungal Diversity 2013年第4期61卷 75-88页

作者： nelson b.Lima Marcus Vinicius de A.batista Marcos A.De Morais Jr Maria A.G.barbosa Sami J.Michereff Kevin D.Hyde Marcos P.S.Câmara Departamento de Agronomia Universidade Federal Rural de Pernambuco52171-900 RecifeBrazil Departamento de Genética Universidade Federal de Pernambuco50732-970 RecifeBrazil Embrapa Semiárido 56302-970 PetrolinaBrazil Institute of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand

Colletotrichum species are the most important and widespread form of decay affecting mango fruit *** this study,Colletotrichum species associated with fruit anthracnose isolated from mango in northeastern brazil were subject to molecular and morphological *** partial sequences of the glyceraldehyde-3-phosphate dehydrogenase gene of 143 Colletotrichum isolates was amplified,as an initial measure of genetic diversity.A subset of 47 isolates,selected to represent the range of genetic diversity and geographic origin,were further sequenced using the partial actin,β-tubulin,calmodulin,glutamine synthetase genes and rDNA-ITS *** multilocus sequence analysis,together with a critical examination of the phenotypic characters,revealed four previously described species(Colletotrichum asianum,Colletotrichum fructicola,Colletotrichum tropicale and Colletotrichum karstii)and one new *** new species is introduced as Colletotrichum dianesei and formally described,illustrated and compared with similar *** *** and *** have previously been reported from mango,while the other species represent the first report associated with the mango fruits *** species are reported for the first time associated with the mango fruits in brazil.

关键词： Multilocus phylogeny Morphology New species Plant disease

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New advances in EMG control methods of anthropomorphic prosthetic hand

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Science China(Technological Sciences) 2017年第12期60卷 1978-1979页

作者： WANG YiXuan LIU He LENG DongLiang GAO Wei CAI MaoLin XU WeiQing ZHANG Xiaohua douglas SHI Yan School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Faculty of Health Sciences University of Macao Taipa Macao The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310058 China beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Prosthetic hands are becoming more and more popular among people without a hand and it is able to perform certain manual operations in *** biology,action potentials trigger muscle contractions,and surface electromyography（sEMG）signals are the sum of action potentials under the skin exposed by the electrodes（via sebum and solution conduction）.

关键词： New advances in EMG control methods anthropomorphic

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On the Electric Conductivity of Homoionic Montmorillonites at Low Water Content

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Journal of Environmental Science and Engineering(b) 2016年第9期5卷 419-424页

作者： nelson Juan Garcia Department of Chemistry INQUISUR CONICET-UNS University National of Sur Bahia Blanca B8OOOCPB Argentina

bibliographic reports on the electric conductivity of pure homoionic montmorillonite at low water content were analyzed in order to stress a general behavior of conductivity. At low water content, the conductivity is attributed to a mechanism of charge transport involving protons due to the influence of the electric field of the exchangeable cations on water molecules at the solvation shell. Conductivity was analyzed in relation with the polarizing power （ionic potential） of the exchangeable cations and with the influence of the connectivity within samples. The general conclusion stressed is that the connectivity due to the association between 2：1 unit layers （clay fabric） is the main factor on the experimental or ＂macroscopic＂ electric conductivity of pure homoionic montmorillonite at low water content. Considerations on the experimental conditions of different bibliographic reports were also made. The conclusion and the considerations made on experimental conditions are a good starting point for future researches on electric conductivity ofhomoionic montmorillonite at low water content.

关键词： Electrical conductivity homoionic pure montmorillonite ionic potential proton connectivity association between 2:1 unit layers.

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关于人工智能的最新假说——知识的阈值理论

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计算机科学 1989年第1期16卷 1-6页

作者： douglas b.Lenat Edward A.Feigenbaum 何华灿吕艳

两位作者根据人工智能研究的已有成果,在1937年8月的国际人工智能会议上提出了三个基本假说:(1)知识原型——一个能有效地完成某项复杂任务的程序,必须具备相应领域的大量知识。(2)宽度假设——智能系统(程序)还应具备两种应付意外情况... 详细信息

两位作者根据人工智能研究的已有成果,在1937年8月的国际人工智能会议上提出了三个基本假说:(1)知识原型——一个能有效地完成某项复杂任务的程序,必须具备相应领域的大量知识。(2)宽度假设——智能系统(程序)还应具备两种应付意外情况的能力:首先,它可以退出专业领域,转而应用一般性知识;其次,系统能够应用类比法推理,以便借用其它领域的知识。(3) 实验验证假设——人们关于人工智能的思想和方法必须在大型的问题求解系统中得到检验。这三个假说统称为知识的阈值假说。这一假说的提出,引起了学术界的广泛注意。有人认为它从更高层次上抓住了当前人工智能发展的关键问题,将给已经陷入困境的人工智能研究带来新的生机,使其产生质的飞跃,从而推动人工智能研究进入一个新的发展时期。有的则认为它只不过是一篇空泛的思辩性文章。是非曲直让读者评说,现将其精华部分译出。

关键词：人工智能阈值假说

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Multiple Endemic Solutions in an Epidemic Hepatitis b Model without Vertical Transmission

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Applied Mathematics 2014年第16期5卷 2518-2529页

作者： nelson Owuor Onyango School of Mathematics CBPS University of Nairobi Nairobi Kenya

This paper examines the dynamics of Hepatitis b via a Susceptible Exposed Infectious Recovered (SEIR) type epidemic model. Previous studies have shown that Hepatitis b is characterized by multiple endemic solutions, a matter which may be of concern in developing control strategies. We identify the possible causes of multiple endemic solutions in a Hepatitis b model and conclude that the dependance of the probability of carriage development ?(q(Λ)) on the force of infection (Λ) is the main reason for multiple endemicity. Other factors such as a large proportion of infants that are not vaccinated (ω) may also enhance the possibility of multiple endemicity. The role of carriers may also play a key role in the possibility of such complex dynamics, i.e., when infectiousness of carriers-(α)?is high, the probability of existence of multiple endemic equilibrium solutions is increased. In our arguments, the traditional reproduction number R0G(0) bility of disease-free equilibrium.

关键词： SEIR Epidemic Models Endemic Equilibriums Hepatitis b

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Analyzing Virtual World Region Fidelity on Scalability and Simulation Performance

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Open Journal of Modelling and Simulation 2015年第3期3卷 126-135页

作者： Sean C. Mondesire Jonathan Stevens Rebecca Leis douglas b. Maxwell US Army Research Laboratory Orlando FL USA Institute for Simulation and Training University of Central Florida Orlando FL USA

Virtual world simulation offers tremendous potential opportunities to improve, and optimize, individual and collective echelon training for the military. The US Army Research Laboratory (ARL) Military Open Simulator Enterprise Strategy (MOSES) project’s charter is to investigate simulation-based training technology for use in military specific training domains. Of particular interest are attributes of virtual worlds such as geographically distributed large-scale trainee support. We have initiated a series of experiments to determine appropriate benchmarks for simulator performance and to determine appropriate independent variables in order to create a robust predictive model that will enable virtual world training scenario designers to calculate, a priori, the number of trainees that may synchronously operate in a virtual world. The present paper’s purposes were to determine the effect that virtual world region fidelity had on server performance and determine whether this independent variable would be appropriate for inclusion into our predictive model. We found that region fidelity had a statistically significant effect on the simulator’s processor memory usage but had no significant effect on the simulator’s vertical scalability, CPU usage nor network performance. In this paper, we discourse on the purpose of this research, our experimental methodology and results, and discuss the significance of our findings.

关键词： Region Fidelity Vertical Scaling Virtual World Simulation Performance Analysis Distributed Simulation

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An implementation strategy to quantify the marine microbial carbon pump and its sensitivity to global change

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National Science Review 2018年第4期5卷 474-480页

作者： Carol Robinson douglas Wallace Jung-Ho Hyun Luca Polimene Ronald benner Yao Zhang Ruanhong Cai Rui Zhang Nianzhi Jiao University of East Anglia School of Environmental Sciences Oceanography Department Dalhousie University Hanyang University Department of Marine Science and Convergence Engineering Plymouth Marine Laboratory University of South Carolina Department of Biological Sciences and School of the EarthOcean and Environment State Key Laboratory of Marine Environmental Science and Institute of Marine Microbes and Ecospheres

INTRODUCTION The persistence of the vast pool of recalcitrant dissolved organic carbon(RDOC)in the deep ocean is fundamental to both global carbon cycling and global ***,quantitative understanding of the mechanisms that produce and utilize RDOC is still in its *** from a conceptual framework to quantitative understanding in marine carbon cycling can take the international research community several decades—precious time

关键词： MCP An implementation strategy to quantify the marine microbial carbon pump and its sensitivity to global change

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