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Deletion or underexpression of the Y-chromosome genes CDY2 and HSFY is associated with maturation arrest in American men with nonobstructive azoospermia

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Asian journal of Andrology 2012年第5期14卷 676-682页

作者： peter j Stahl Anna N Mielnik Christopher E Barbieri peter N Schlegel Darius A Paduch Department of Urology Weill Cornell Medical CollegeNew York Presbyterian HospitaI-CornellNew YorkNY 10065USA

Maturation arrest （MA） refers to failure of germ cell development leading to clinical nonobstructive azoospermia. Although the azoospermic factor （AZF） region of the human Y chromosome is clearly implicated in some cases, thus far very little is known about which individual Y-chromosome genes are important for complete male germ cell development. We sought to identify single genes on the Y chromosome that may be implicated in the pathogenesis of nonobstructive azoospermia associated with MA in the American population. Genotype-phenotype analysis of 132 men with Y-chromosome microdeletions was performed. Protein-coding genes associated with MA were identified by visual analysis of a genotype-phenotype map. Genes associated with MA were selected as those genes within a segment of the Y chromosome that, when completely or partially deleted, were always associated with MA and absence of retrievable testicular sperm. Expression of each identified gene transcript was then measured with quantitative RT-PCR in testicular tissue from separate cohorts of patients with idiopathic MA and obstructive azoospermia. Ten candidate genes for association with MA were identified within an 8.4-Mb segment of the Y chromosome overlapping the AZFb region. CDY2and HSFYwere the only identified genes for which differences in expression were observed between the MA and obstructive azoospermia cohorts. Men with obstructive azoospermia had 12-fold higher relative expression of CDY2transcript （1.33__.0.40 vs. 0.11＋_0.04; P=O.O003） and 16-fold higher expression of HSFYtranscript （0.78__.0.32 vs. 0.05_0.02; P=O.O005） compared to men with MA. CDY2 and HSFYwere also underexpressed in patients with Sertoli cell only syndrome. These data indicate that CDY2and HSFYare located within a segment of the Y chromosome that is important for sperm maturation, and are underexpressed in testicular tissue derived from men with MA. These observations suggest that impairments in CDY2 or HSFYexpression could be impli

关键词： CDY1 protein CDY2 protein genetics histology HSFY human make infertility nonobstructive azoospermia spermato-genesis sperm maturation

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The Structure of Low Frequency Phenomena in the Tropics and Its Interaction with the Extratropics

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Advances in Atmospheric Sciences 1992年第1期9卷 1-16页

作者： peter j.Webster 董敏 Department of Meteorology The Pennsylvania Stale University PA 16802 USA Academy of Meteorological Science State Meteorological Administration Beijing 100081 PRChe structure of planetary scale low freonency phenomena in the tropics is studied and an attempt is made to determine its influence and interactions with phenomena at higher latitudes.In the tropics it is found that the majority of the variance in the zonal wind structure is made up in wave numbers I and 2. During warm events in the Pacific Ocean when the Southern Oscillation Index is negative almost all of the variance resides in the gravest mode which undergoes a 40° eastward phase shift. Meanwhile the second logitudinal mode almost disappears. On the other hand the meridional wind field possesses maximum amplitude at higher wave numbers. However near the equatorthe amplitude is small with extreme values occurring in the subtropics. The difference in scale and the location of cxtrcma of the meridional and zonal wind components indicate that the tropical atmosphere is responding to two different driving mechanisms.Correlation analyses between variations of the zonal wind at reference points along the equator with variations of component elsewhere show that there are strong logitudinal connections. The strongest correlations between the tropics and higher latitudes exist in the region of the equatorial westerlies. In fact stronger correlations occur between variations in U anywhere along the equator and the middle latitudes to the north and south of the equatorial westerlies than to the latitudes immediately to the north and south of the reference points. We interpret this "remote" correlation pattern as indicating a two-stage teleconnection process which emphasizes the importance of the equatorial tropical westerlies of the Pacific Ocean as a "corridor" of communication between the low and high latitudes. The regionality of the correlations confirms to some extent recent theoretical development regarding trapped equatorial modes. Finally

The structure of planetary scale low freonency phenomena in the tropics is studied, and an attempt is made to determine its influence and interactions with phenomena at higher *** the tropics, it is found that the majority of the variance in the zonal wind structure is made up in wave numbers I and 2. During warm events in the Pacific Ocean, when the Southern Oscillation Index is negative, almost all of the variance resides in the gravest mode which undergoes a 40° eastward phase shift. Meanwhile, the second logitudinal mode almost disappears. On the other hand, the meridional wind field possesses maximum amplitude at higher wave numbers. However, near the equator,the amplitude is small with extreme values occurring in the subtropics. The difference in scale and the location of cxtrcma of the meridional and zonal wind components indicate that the tropical atmosphere is responding to two different driving *** analyses between variations of the zonal wind at reference points along the equator with variations of component elsewhere show that there are strong logitudinal connections. The strongest correlations between the tropics and higher latitudes exist in the region of the equatorial westerlies. In fact, stronger correlations occur between variations in U anywhere along the equator and the middle latitudes to the north and south of the equatorial westerlies than to the latitudes immediately to the north and south of the reference points. We interpret this 'remote' correlation pattern as indicating a two-stage teleconnection process which emphasizes the importance of the equatorial tropical westerlies of the Pacific Ocean as a 'corridor' of communication between the low and high latitudes. The regionality of the correlations confirms, to some extent, recent theoretical development regarding trapped equatorial modes. Finally, time lagged correlations from plus and minus six months between variations of U and OLR indicate that the interactio

关键词： In The Structure of Low Frequency Phenomena in the Tropics and Its Interaction with the Extratropics

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Absolute characterization of high numerical aperture microscope objectives utilizing a dipole scatterer

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Light(Science & Applications) 2021年第12期10卷 2342-2348页

作者： jörg S.Eismann Martin Neugebauer Klaus Mantel peter Banzer Institute of Physics University of GrazNAWI GrazUniversitätsplatz 58010 GrazAustria Max Planck Institute for the Science of Light Staudtstr.291058 ErlangenGermany Institute of Optics Information and PhotonicsUniversity Erlangen-NurembergStaudtstr.7/B291058 ErlangenGermany

Measuring the aberrations of optical systems is an essential step in the fabrication of high precision optical *** a characterization is usually based on comparing the device under investigation with a calibrated reference ***,when working at the cutting-edge of technology,it is increasingly difficult to provide an even better or well-known reference *** this manuscript we present a method for the characterization of high numerical aperture microscope objectives,functioning without the need of calibrated reference *** technique constitutes a nanoparticle,acting as a dipole-like scatterer,that is placed in the focal volume of the microscope *** light that is scattered by the particle can be measured individually and serves as the reference wave in our *** the well-characterized scattered light as nearly perfect reference wave is the main idea behind this manuscript.

关键词： characterization scatter scattered

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Guest Editorial:Special Section on Active Distribution Networks:Markets,Operations,Planning,and Regulation

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journal of Modern Power Systems and Clean Energy 2023年第1期11卷 1-2页

作者： peter Palensky Qixin Chen Marcos j.Rider Delft University of Technology DelftNetherlands Tsinghua University BeijingChina University of Campinas Sao PauloBrazil

THE power system is in change,and the most fundamental changes are happening in the distribution *** passive consumers get active and smart,energy storage and distributed generation appears,and the“grid edge”is upgraded with Intenet of Things(IoT).Gone are the days where distribution infrastructure consisted of passive assets,dimensioned for the worst case of load.

关键词： passive IoT distribution

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Claudin-11 and occludin are major contributors to Sertoli cell tight junction function, in vitro

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Asian journal of Andrology 2016年第4期18卷 620-626页

作者： Mark j McCabe Caroline FH Foo Marcel E Dinger peter M Smooker peter G Stanton Male Fertility Regulation Laboratory Hudson Institute of Medical Research Monash Medical Centre Clayton Victoria 3168 Australia School of Applied Sciences Royal Melbourne Institute of Technology University Bundoora Victoria 3088 Australia Kinghorn Centre for Clinical Genomics Garvan Institute of Medical Research Darlinghurst New South Wales 2010 Australia St Vincent's Clinical School UNSW Sydney New South Wales 2052 Australia.

The Sertoli cell tight junction （T j） is the key component of the blood-testis barrier, where it sequesters developing germ cells undergoing spermatogenesis within the seminiferous tubules. Hormonally regulated claudin-11 is a critical transmembrane protein involved in barrier function and its murine knockout results in infertility. We aimed to assess quantitatively the significance of the contribution of claudin-11 to Tj function, in vitro, using siRNA-mediated gene silencing. We also conducted an analysis of the contribution of occludin, another intrinsic transmembrane protein of the Tj. Silencing of claudin-11 and/or occludin was conducted using siRNA in an immature rat Sertoli cell culture model. Transepithelial electrical resistance was used to assess quantitatively Tj function throughout the culture. Two days after siRNA treatment, cells were fixed for immunocytochemical localization of junction proteins or lyzed for RT-PCR assessment of mRNA expression. Silencing of claudin-11, occludin, or both resulted in significant decreases in Tj function of 55% （P 〈 0.01）, 51% （P 〈 0.01）, and 62% （P 〈 0.01）, respectively. Data were concomitant with significant decreases in mRNA expression and marked reductions in the localization of targeted proteins to the Sertoli cell Tj. We provide quantitative evidence that claudin-11 contributes significantly （P 〈 0.01） to Sertoli cell Tj function in vitro. Interestingly, occludin, which is hormonally regulated but not implicated in infertility until late adulthood, is also a significant （P 〈 0.01） contributor to barrier function. Our data are consistent with in vivo studies that clearly demonstrate a role for these proteins in maintaining normal Tj barrier structure and function.

关键词： blood-testis barrier claudin-11 occludin Sertoli cell tight junction siRNA

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Using Inductance as a Tuning Parameter for RF Meta-atoms

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Nano-Micro Letters 2012年第2期4卷 103-109页

作者： Derrick Langley Ronald A.Coutu peter j.Collins Air Force Institute of Technology Wright-Patterson Air Force Base

The resonant frequency of metamaterials structured with split ring resonator(SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz to 2.18 GHz.

关键词： Inductance Meta-atom Metamaterial Split Ring Resonator Radio Frequency Resonance

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Algorithms for enumeration problem of linear congruence modulo m as sum of restricted partition numbers

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Frontiers of Mathematics in China 2015年第1期10卷 69-89页

作者： Tian-Xiao HE peter j. -S. SHIUE Department of Mathematics Illinois Wesleyan University Bloomington IL 61702 USA Department of Mathematical Sciences University of Nevada Las Vegas Las Vegas NV 89154-4020 USA

We consider the congruence x1＋ x2 ＋… ＋ xr - c （mod m）, wherem and r are positive integers and c ∈Zm ：= {0, 1, ..., m- 1} （m ≥ 2）. Recently,W.-S. thou, T. X. He,and peter j.-S. Shiue considered the enumerationproblems of this congruence, namely, the number of solutions with the restriction x1≤~ x2≤ ... ≤ xr, and got some properties and a neat formula ofthe solutions. Due to the lack of a simple computational method for calculating the number of the solution of the congruence, we provide an algebraic and a recursive algorithms for those numbers. The former one can also give a new and simple approach to derive some properties of solution numbers.

关键词： Congruence multiset congruence solution restricted integerpartition

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Variability in total cost of vehicle ownership across vehicle and user profiles

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Communications in Transportation Research 2022年第1期2卷 206-221页

作者： Yulu Guo j.Andrew Kelly j.peter Clinch UCD Environmental Policy University College DublinRichviewClonskeaghIreland EnvEcon Decision Support 11 Priory Office ParkBlackrockDublinIreland UCD Earth Institute and UCD Geary Institute for Public Policy BelfieldDublin4Ireland

Widespread adoption of electric vehicles(EVs)is a common and critical component of international strategies to mitigate environmental pollution,climate change and oil *** ability of consumers to assess the total cost of ownership(TCO)of EVs relative to internal combustion engine vehicles(ICEVs)remains an important factor for EV *** TCO of vehicles is not universal across different car segments and user *** analyse and compare the TCO of ICEVs and EVs from 17 car segments across short-and long-term ownership periods,and further advance existing TCO approaches by integrating detailed activity-based driving profiles,taxation,grant structures and *** show that EV options in the most popular Irish car segments have existing battery EV options with a TCO averaging respectively 26% and 42% less than their equivalent petrol and diesel ICEV options over a 4-year ownership term when the current grant is *** integrated method for granular TCO evaluation offers important insights for this market and affords scope to investigate how changes in travel patterns,car-segment pricing,taxation,grant policy,fuel costs,and carbon pricing and other transport policies can all affect TCO values over time across a broad range of market offerings.

关键词： Total cost of ownership Electric vehicles(EVs) Driving profile Car segments Depreciation cost Transport Climate policy

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Effect of restricted feeding on hen performance,egg quality and organ characteristics of individual laying hens

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Animal Nutrition 2023年第3期14卷 141-151页

作者： Doreen O.Anene Yeasmin Akter peter C.Thomson peter Groves Cormac j.O'Shea Department of Animal Science School of BiosciencesUniversity of NottinghamLoughboroughLE125RDUnited Kingdom School of Life and Environmental Sciences Faculty of ScienceUniversity of SydneyCamdenNSW 2570Australia Sydney School of Veterinary Science Faculty of SciencePoultry Research FoundationUniversity of SydneyCamdenNSW 2570Australia Department of Bioveterinary and Microbial Sciences Technological University of the Shannon:Midlands MidwestDublin RoadAthloneCo WestmeathN37 HD68Ireland

This study was to assess the impact of permanent or temporary restricted feeding on laying hen production traits,physiology,and egg *** hundred and forty individually housed ISA Brown hens were monitored across 2 phases,assigned to 3 treatments:ad libitum feeding(ALF),temporary restricted feeding(TRF)and permanent restricted feeding(PRF),n=80 hens per *** Phase 1(P1),22 to40 weeks,the TRF and PRF hens were offered 115 g of feed *** Phase 2(P2),41 to 46 weeks,the TRF hens were transitioned to ALF status while the ALF and PRF hens remained as in *** 35 to 40 weeks,eggs were collected once weekly from 15 hens per treatment and assessed for differences in albumen,yolk,and shell *** 45 weeks,10 hens each from the ALF and PRF groups were euthanized and differences in organ characteristics were *** P1,feed intake,feed to egg conversion ratio and body weight(BW)change were lower(P<0.01),while albumen height and Haugh unit were higher(P<0.01)in both PRF and TRF hen treatments compared to hens allocated the ALF *** P2,TRF and ALF hens had a higher egg production and egg mass than PRF(P<0.01)than *** weight change in P2 was higher in TRF and similar in both ALF and PRF,while feed intake and feed conversion ratio were higher in TRF followed by ALF and least in the PRF treatment group(P<0.01).At 45 weeks ALF hens had a greater abdominal fat pad weight and fatty liver haemorrhagic syndrome lesion score compared to *** hens to 115 g of feed per day from point of lay restrained BW,improved feed conversion ratio and albumen quality and reduced abdominal fat pad deposition and clinical signs of fatty liver haemorrhagic syndrome in individually housed laying hens.

关键词： Restricted feeding Albumen quality Fatty liver haemorrhagic syndrome Abdominal fat Laying hen Body weight

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Enhancing prognostic accuracy in predicting rectal neuroendocrine neoplasms

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World journal of Gastroenterology 2024年第37期30卷 4087-4089页

作者： Renin peter AA Raj Abdulqadir j Nashwan Department of Medicine Aston Medical SchoolBirmingham B47ETUnited Kingdom Department of Nursing&Midwifery Research Hamad Medical CorporationDoha 3050Qatar

The recently published retrospective study introduces the GATIS score,a new predictive model for rectal neuroendocrine *** analyzing data from a large Chinese multicenter cohort,the study shows that the GATIS score,incor-porating tumor grade,T stage,tumor size,age,and prognostic nutritional index,demonstrates superior predictive power for overall survival and progression-free survival compared to traditional World Health Organization grade and tumor,nodes and metastases staging *** editorial aims to discuss the impor-tance of the GATIS score,its potential impact on clinical practice,and the strengths and limitations of the ***,it explores the significance,methodology,and clinical implications of these findings.

关键词： Rectal neuroendocrine neoplasm Nomogram Random forest Prognosis Overall survival Progression-free survival

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