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A model for the control of DNA integrity by the sperm nuclear matrix

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Asian Journal of Andrology 2015年第4期17卷 610-615页

作者： Joanna E Gawecka Jordi Ribas-Maynou Jordi Benet w steven ward Clinical and Translational Research Program Universityof Hawaii Cancer Center Honolulu HI USA Cell BiologyUnit Cell Biology Phisiology and Immunology DepartmentMedicine Faculty Universitat Autonoma de Barcelona08193 Bellaterra Spain Center of Male Infertility andAnalysis de Barcelona Edifici Eureka PBM5 Parc deRecerca de la UAB Campus de la UAB 08193 BellaterraSpain Institute for Biogenesis Research Departmentof Anatomy Biochemistry and Physiology Honolulu HIUSA Department of Obstetrics Gynecology and Women'sHealth John A. Burns School of Medicine University ofHawaii at Manoa. Honolulu. HI 96822. USA.

The highly condensed chromatin of mammalian spermatozoa is usually considered to be biologically inert before fertilization. However, we have demonstrated that even in this compacted state, sperm chromatin is subject to degradation at open configurations associated with the nuclear matrix through a process we have termed sperm chromatin fragmentation （SCF）. ＂[his suggests that a mechanism exists to monitor the health of spermatozoa during transit through the male reproductive tract and to destroy the genome of defective sperm cells. The site of DNA damage in SCF, the matrix attachment sites, are the same that we hypothesize initiate DNA synthesis in the zygote. when sperm that have damaged DNA are injected into the oocyte, the newly created zygote responds by delaying DNA synthesis in the male pronudeus and, if the damage is severe enough, arresting the embryo＇s development. Here we present a model for paternal DNA regulation by the nuclear matrix that begins during sperm maturation and continues through early embryonic development.

关键词： DNA mammalian spermatozoa

Pum 1 sequesters apoptosis during spermatogenesis

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Asian Journal of Andrology 2012年第4期14卷 513-513页

作者： w steven ward Department of Anatomy Biochemistry and Physiology Institute for Biogenesis Research John A. Burns School of Medicine Universityof Hawaii at Manoa Honolulu HI 96822 USA

RNA binding proteins have long been known to play a role in spermatogenesis. The laboratory of Norman Hecht was one of the leaders in this field, having characterized three RNA binding proteins that regulate mRNAs during sperm differentiation. Polypyrimidine tract-binding pro- tein 2 （PTB2） has two functions--stabilizing mRNA transcripts in the cytoplasm and being involved in splicing,l Using in vivo cross- linking of protein to RNA, several mRNA and small RNA targets were identified in the testis.2 Translin is another protein that both stabilizes mRNAs from a specific transcription factor, and is associated with small RNAs.3 Perhaps the most interesting is the DNA/RNA binding protein MSY2. At low concentrations,

关键词： MALE GERM-CELLS BINDING PROTEIN RNA MSY2

A new Speedy/RINGO protein may help regulate male meiosis

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Asian Journal of Andrology 2011年第3期13卷 363-363页

作者： Yukiko Yamazaki w steven ward Institute for Biogenesis Research University of Hawaii at Manoa Honolulu HI 96822 USA

Reproductive biology, although seen as a specialty study area, has many unique biology models that offer insight into the regulation of cellular processes that are shared by many different cell types. The most celebra... 详细信息

关键词： Biology Regulations Cell cycle Testes Meiosis Proteins Protein products Lates Cells Lymphocytes

Determination of double-and single-stranded DNA breaks in bovine sperm is predictive of their fertilizing capacity

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Journal of Animal Science and Biotechnology 2023年第1期14卷 134-151页

作者： Jordi Ribas‑Maynou Ariadna Delgado‑Bermúdez Yentel Mateo‑Otero Estel Vinolas Carlos O.Hidalgo wsteven ward Marc Yeste Biotechnology of Animal and Human Reproduction(TechnoSperm) Faculty of SciencesInstitute of Food and Agricultural TechnologyUniversity of GironaC/Maria Aurèlia Campany69ES‑17003 GironaSpain. Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaES‑17003 GironaSpain. Institute for Biogenesis Research Department of AnatomyBiochemistry&PhysiologyJohn A.Burns School of MedicineUniversity of Hawaii at ManoaHonoluluHI 96822USA. Department of Animal Selection and Reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)ES‑33394 GijónSpain. Catalan Institution for Research and Advanced Studies(ICREA) ES‑08010 BarcelonaSpain.

Background:The analysis of chromatin integrity has become an important determinant of sperm *** frozenthawed bovine sperm,neither the sequence of post-thaw injury events nor the dynamics of different types of sperm DNA breaks are well *** aim of the present work was to describe such sperm degradation aftermath focusing on DNA damage dynamics,and to assess if this parameter can predict pregnancy rates in ***:A total of 75 cryopreserved ejaculates from 25 Holstein bulls were evaluated at two post-thawing periods(0-2 h and 2-4 h),analyzing global and double-stranded DNA damage through alkaline and neutral Comet assays,chromatin deprotamination and decondensation,sperm motility,viability,acrosomal status,and intracellular levels of total ROS,superoxides and *** of 59,605 females was conducted using sperm from the same bulls,thus obtaining the non-return to estrus rates after 90 d(NRR).Results showed an increased rate of double-stranded breaks in the first period(0-2 h:1.29±1.01%/h vs.2-4 h:0.13±1.37%/h;Pwhereas the rate of sperm with moderate+high single-stranded breaks was higher in the second period(0-2 h:3.52±7.77%/h vs.2-4h:21.06±11.69%/h;Pwas different between the two periods(0-2 h:-4.49±1.79%/h vs.2-4 h:-2.50±3.39%/h;P=0.032),but the progressive motility decrease rate was constant throughout post-thawing incubation(0-2 h:-4.70±3.42%/h vs.2-4 h:-1.89±2.97%/h;P>0.05).Finally,whereas no correlations between bull fertility and any dynamic parameter were found,there were correlations between the NRR and the basal percentage of highly-damaged sperm assessed with the alkaline Comet(Rs=-0.563,P=0.003),between NRR and basal progressive motility(Rs=0.511,P=0.009),and between NRR and sperm with high ROS at 4 h post-thaw(Rs=0.564,P=0.003).Conclusion:The statistically significant correlations found between intracellular ROS,sperm viability,sperm motility,DNA damage

关键词： Cattle Chromatin Comet test DNA damage Fertility Sperm Sperm quality

Tsunami Balls:A Granular Approach to Tsunami Runup and Inundation

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Communications in Computational Physics 2008年第1期3卷 222-249页

作者： steven N.ward Simon Day Institute of Geophysics and Planetary Physics University of CaliforniaSanta CruzCA 95064USA.

This article develops a new,granular approach to tsunami runup and *** small grains employed here are not fluid,but bits,or balls,of tsunami *** careful formulation of the ball accelerations,both wave-like and flood-like behaviors are accommodated so tsunami waves can be run seamlessly from deep water,through wave breaking,to the final surge onto shore and back *** deep water,tsunami balls track according long wave ray *** land,tsunami balls behave like a water *** shallow water,the balls embody both deep water and on land *** modeling several 2-D and 3-D cases,we find that wave breaking generally causes relative runup to increase with beach slope and wave period and decrease with input wave *** of their highly non-linear nature,runup and inundation are best considered to be random processes rather than deterministic *** and observations hint that for uniform input waves,normalized runup statistics everywhere follow a single skewed distribution with a spread between 1/2 and 2 times its mean.

关键词： water wave tsunami run up.

Comparing outcomes from the two most recognized acupuncturist workforce surveys

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Journal of Integrative Medicine 2017年第1期15卷 37-43页

作者： steven H. Stumpf Kory ward-Cook Clifford R. Carr Health Administration Program California State University at NorthridgeNorthridgeCalifornia 91330USA National Certification Commission of Acupuncture and Oriental Medicine JacksonvilleFlorida 32202USA Clifford R.Carr 1743 PenmarAvenue#3VeniceCalifornia 90291USA

OBJECTIVE： To determine the informational consistency produced by the two most recent independent surveys and draw a conclusion whether the data would be sufficient for the National Center for Health workforce Analysis and Bureau of Labor and Statistics consideration. METHODS： This paper compares workforce outcomes collected by the two most prominent acupuncture entities that have produced the most useful acupuncturist workforce data （California Acupuncture Board 2015 Occupational Analysis and the National Certification Commission of Acupuncture and Oriental Medicine^2013 Job Analysis） at national and state levels. RESULTS： Findings based upon the most compatible survey questions showed the following： more than 70% of acupuncturists work fewer than 40 hours weekly; approximately 76% work in solo practice or in shared space with other acupuncturists; more than 70% of the national sample have been in practice 15 years or less; and median income is between $40 000 and $50 000. A preponderance of acupuncturists is less than 50 years of age, and fewer than 15% of all respondents have been in practice more than 20 years. CONCLUSION： Basic workforce information is a necessary precursor for conducting workforce projections. It is useful to track the expansion or contraction of any given profession. Tracking influences subsequent planning for the profession based upon reliable and valid information about its growth. The ability of the profession to collect its own workforce data is paramount to workforce projection models. Any future survey should be a shared project that follows guidelines supported by the National Center for Health workforce Analysis.

关键词： acupuncture workforce survey outcome assessment (health care) income

Availability and Timing of Fathead Minnow Supplementation Influence Largemouth Bass Survival and Production in Rearing Ponds

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Open Journal of Animal Sciences 2020年第3期10卷 337-345页

作者： Matthew J. ward steven R. Chipps South Dakota Department of Game Fish and Parks Blue Dog Lake State Hatchery Waubay USA U.S. Geological Survey South Dakota Cooperative Fish and Wildlife Research Unit McFadden Biostress Laboratory Department of Natural Resource Management South Dakota State University Brookings USA

Adjustments to rearing practices should be justified with increases in production, stocking success, or angler satisfaction. Largemouth bass (Micropterus salmoides) production was assessed between hatchery ponds where fish were restricted to an invertebrate diet or received supplemental fathead minnow (Pimephales promelas) forage during 2015. At harvest, age-0 bass yield was 4.5 times greater and average fish length was 38 mm longer, in the pond that received fathead minnow. In 2016, a second study evaluated the timing of minnow supplementation that included earlier stockings of small fathead minnow (with larger (>30 mm) minnows. with earlier supplementation, bass yield was 2.3 times greater and fish averaged 14 mm longer at harvest. Bass survival was approximately 38% higher during 2015 when supplementation occurred and 25% higher during 2016 when minnow supplementation began earlier. Our findings show invertebrate forage was probably limiting bass production in hatchery ponds and supplementing with appropriately-sized fathead minnows increased age-0, largemouth bass production.

关键词： Largemouth Bass Culture Pond-Rearing Fathead Minnow Stocking

Bright spots for inland fish and fisheries to guide future hydropower development

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water Biology and Security 2022年第1期1卷 81-99页

作者： william M.Twardek Ian G.Cowx Nicolas w.R.Lapointe Craig Paukert T.Douglas Beard Elena M.Bennett David Browne Andrew K.Carlson Keith D.Clarke Zeb Hogan Kai Lorenzen Abigail J.Lynch Peter B.McIntyre Paulo Pompeu Mark Rogers Alexis Sakas william w.Taylor Taylor D.ward Zeenatul Basher steven J.Cooke Fish Ecology and Conservation Physiology Laboratory Department of Biology and Institute for Environmental StudiesCarleton University1125 Colonel By DrOttawaON K1S 5B6Canada Fisheries Institute at the University of Hull Cottingham RdHullHU67RXUnited Kingdom Canadian wildlife Federation 350 Michael Cowpland DrKanataONK2M 2W1Canada U.S.Geological Survey Missouri Cooperative Fish and Wildlife Research UnitUniversity of MissouriColumbiaMO65211United States U.S.Geological Survey National Climate Adaptation Science Center12201 Sunrise Valley DriveMS-516RestonVA20192United States McGill School of Environment McGill University845 Sherbrooke St WMontrealQuebec H3A 0G4Canada Princeton Environmental Institute and Department of Ecology and Evolutionary Biology Princeton UniversityM30 Guyot HallPrincetonNJ08544United States Ecological Sciences Section Science Branch Fisheries and Oceans CanadaCanadaPO Box/CP 5667St.John'sNewfoundland and LabradorA1C 5X1Canada University of Nevada Reno.4505 S Maryland PkwyLas VegasNV89154United States Fisheries and Aquatic Sciences School of Forest Resources and ConservationUniversity of Florida7922 NW 71st StreetGainesvilleFL32653United States Department of Natural Resources Cornell UniversityIthacaNY14853United States Departamento de Biologia Universidade Federal de LavrasAquenta SolLavrasState of Minas Gerais37200-900Brazil U.S.Geological Survey Tennessee Cooperative Fishery Research UnitTennessee tech UniversityCookevilleTN38505United States The Nature Conservancy 6375 Riverside DriveSuite 100DublinOH43017United States Michigan State University Department of Fisheries and WildlifeEast LansingMI48823United States

Hydropower production is one of the greatest threats to fluvial ecosystems and freshwater *** that we have entered the Anthropocene,there is an opportunity to reflect on what might constitute a‘sustainable’Anthropocene in the context of hydropower and riverine fish *** elements of existing practices that promote favorable social-ecological outcomes(i.e.,‘bright spots’)is timely given that there are plans to expand hydropower capacity in previously undammed rivers,intensify dam development in some of the world's largest river systems,and re-license existing *** approach this from a pragmatic perspective:for the foreseeable future,hydropower will likely remain an important source of renewable *** offer support for moving toward a more‘sustainable’Anthropocene,we provide syntheses of best practices during the siting,design,construction,operation,and compensation phases of hydropower development to minimize impacts on inland *** each phase,we offer positive examples(or what might be considered‘bright spots’)pertaining to some of the approaches described within our syntheses,acknowledging that these projects may not be viewed as without ecological and(or)societal detriment by all *** findings underscore the importance of protecting critical habitat and free-flowing river reaches through careful site selection and basinscale planning,infrastructure designs that minimize reservoir effects and facilitate safe passage of fish,construction of hydropower plants using best practices that minimize long-term damage,operating guidelines that mimic natural flow conditions,and compensation that is lasting,effective,inclusive,and locally *** from these‘bright spots’may require engagement of diverse stakeholders,professionals,and governments at scales that extend well beyond a given site,river,or even ***,environmental planning that integrates hydropower development into broader discussions

关键词： Migration Dams Salmon Hydroelectric Flow Socioecological Fish passage Barriers Ecosystems

(Re)drawing Lines in Our Research:Using Policy Mobilities and Network Ethnography to Research Global Policy Networks in Education

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ECNU Review of Education 2023年第4期6卷 646-653页

作者： steven Lewis Australian Catholic University

The flows and frictions of policy networks we are all scholars of policy to some *** a definitive statement is not without merit—after all,we all experience and interact with policy across education,from the“eddies and flows”(Cochrane&ward,2012)of its movements to the“fixities and moorings”(Sheller&Urry,2006)of its *** of whether we explicitly refer to ourselves as“policy researchers,”the various dimensions of education and schooling upon which we choose to putatively focus—including pedagogy,curriculum.

关键词： friction policy education