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Asian Journal of Andrology 2010年第2期12卷 257-262页

作者： h.len G. Tempest Siu Yan Ch.ng David J. Gillott alan h. handyside alan R. Th.mh.ll Darren K. Griffin London Bridge Fertility Gynaecology and Genetics Centre London SEI 9RY UK Bridge Genoma London SE1 9RY UK Department of Biosciences University of Kent Canterbury Kent CT2 7N J UK

It is now well known th.t levels of sperm disomy correlate to levels of infertility （as well as oth.r factors）.Th. risk of perpetuating aneuploidy to th. offspring of infertile males undergoing intracytoplasmic sperm injection （ICSI） h.s become a h.tly debated issue in assisted reproduction;h.wever,th.re remain barriers to th. practical implementation of offering sperm disomy screening in a clinical setting. Th. major barrier is th. operator time taken to analyze a statistically meaningful （sufficient） number of cells. Th. introduction of automated ＇spot counting＇software-h.rdware combinations presents a potential solution to th.s problem. In th.s preliminary validation study,we analyzed 10 patients,both.manually and using a commercially available spot counter. Results sh.w a statistically significant correlation between both.approach.s for scoring of sperm disomy,but no correlation is found wh.n scoring for diploid sperm. Th. most likely explanation for th. latter is an apparent overscoring of two closely associated sperm h.ads as a single diploid cell. Th.se results,and similar furth.r studies th.t will ensue,h.lp to inform cost-benefit analyses th.t individual clinics need to carry out in order to decide wh.th.r to adopt sperm aneuploidy screening as a routine tool for th. assessment of sperm from men requiring ICSI treatment.

关键词： aneuploidy assisted reproductive tech.ologies automation fluorescent in situ h.bridization meth.ds scoring spermatozoa

Assets and tactics in a mating market： Economic models of negotiation offer insigh.s into animal courtsh.p dynamics on th. lek

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Current Zoology 2011年第2期57卷 225-236页

作者： Gail L. PATRICELLI alan h. KRAKAUER Rich.rd MCELREATh Department of Evolution and Ecology University of California Davis CA 95616 USA Department of Anth.opology University of California Davis CA 95616 USA

Economists study negotiation as a series of events--partner ch.ice, information gath.ring, bargaining, etc.--with.each.step of th. process affecting th. outcome of th. next, and th. optimal decision at each.stage depending on th. player＇s bargaining power. Th. context in wh.ch.th.se negotiations occur--th. market--is critical, since players can adjust th.ir beh.viors in response to outside offers. Animals similarly are faced with.sequential decisions regarding courtsh.p： wh. to court, h.w to approach.a potential mate, at wh.t level to display, wh.n to give up, etc. Th.s economic models of negotiation in a market provide a framework in wh.ch.we can view not just th. outcome of courtsh.p （assortative mating）, but also th. process, wh.re each.sex can use tactics to improve th.ir negotiating outcome, using th. assets th.t th.y h.ve available. h.re we propose to use negotiation as a conceptual framework to explore th. factors promoting tactical adjustments during sequential stages of courtsh.p in lekking species. Our goal is to discuss th. utility of negotiation as a h.uristic tool, as well as th. promise and peril of co-opting game th.oretic models from economics to understand animal interactions. We will provide a brief overview of a few areas wh.re we see promise for using negotiation as a framework to understand animal courtsh.p dynamics： ch.ice of a display territory, tactical partner ch.ice for negotiation, approach.ng a potential partner and courtsh.p h.ggling .

关键词： Bargaining Game th.ory Lek Sexual selection Signaling Negotiation

A Modified Neutral-point Voltage Control Strategy for Th.ee-level Inverters Based on Decomposition of Space Vector Diagram

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CES Transactions on Electrical Mach.nes and Systems 2022年第2期6卷 124-134页

作者： Dereje Woldegiorgis h.alan Mantooth Department of Electrical Engineering University of ArkansasFayettevilleAR72701USA

Capacitor voltage imbalance is a significant problem for th.ee-level *** to th. mid-point modulation of th.se inverter topologies,th. neutral point potential moves up or down depending on th. neutral point current direction creating imbalanced voltages among th. two *** imbalanced capacitor voltage causes imbalanced voltage stress among th. semiconductor devices and causes increase output voltage and current *** paper introduces a modified voltage balancing strategy using two-level space vector *** decomposing th. th.ee-level space vector diagram into two-level space vector diagram and redistributing th. dwell times of th. two-level zero space vectors,th. modified voltage balancing meth.d ensures minimal NP voltage *** to th. commonly used NP voltage control meth.d(using 3L SVM[9]),th. proposed modified NP voltage control meth.d offers a sligh.ly h.gh.r neutral-point voltage ripple and output voltage h.rmonics but,it h.s much.lower switch.ng loss,code size and execution time.

关键词： Th.ee-level inverter Neutral-point voltage control Execution time

Precise Electro-th.rmal Power Loss Model of a Th.ee-level ANPC Inverter with.h.brid Si/SiC Switch.s

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Ch.nese Journal of Electrical Engineering 2022年第3期8卷 76-89页

作者： Dereje Woldegiorgis h.alan Mantooth Department of Electrical Engineering University of ArkansasFayettevilleAR 72701USA

h.brid Si/SiC switch.s constituting a parallel connection of a lower current rated SiC MOSFET and a h.gh.r current rated Si IGBT are becoming very attractive solution for designing h.gh.frequency and h.gh.power density power electronic *** to th. complementary nature of Si IGBT devices(smaller inverter cost and smaller conduction loss)and SiC devices(smaller switch.ng loss and h.gh.r junction temperature capability),th.se novel switch.device configurations enable a good tradeoff between cost and efficiency for h.gh.power converter *** such.recent application of h.brid Si/SiC switch.s for efficiency-cost optimization is an Si/SiC h.brid switch.based ANPC inverter proposed in Ref.[30].In Ref.[30]th. topology structure,modulation strategy and th. efficiency-cost benefits of th. proposed ANPC inverter is *** th.s paper a precise electro-th.rmal power loss model for th.s ANPC inverter topology will be presented based on th. modulation strategy of th. inverter and th. operating ch.racteristics of th. Si/SiC h.brid *** power loss model development takes into account h.w th. current sh.ring between th. two internal devices of th. Si/SiC h.brid switch.s and th.ir corresponding gate control meth.d affects th.ir power loss.A brief introduction to th. topology structure and operation principle of th. Si/SiC based ANPC inverter is first h.gh.igh.ed to provide context for readers and th.n a detailed description of th. proposed electro-th.rmal power loss model is *** precision of th. electro-th.rmal power loss model introduced in th.s paper is th.n validated using experimentally measured energy loss,device temperature and inverter efficiency data.

关键词： Cost reduction power loss model efficiency improvement ANPC inverter

Improvement on th. inversion of kernel-driven BRDF model

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Ch.nese Science Bulletin 1999年第1期44卷 76-79页

作者： alan h.Strah.er Department of Geograph. and Centre for Remote Sensing Boston University Boston USA

Kernel-driven model was ch.sen to calculate global albedo in th. project of multiangular remote sensor MODIS. Th. best kernels were selected by th. venerable 'least square' meth.d. Th. result of th.s meth.d was very unstable wh.n only a small amount of angular observations is available. A new criterion h.s been estalish.d, called 'least variance' for th. kernel’s selection. It takes into consideration th. effects of model and measurement based on th. information inverse th.ory. Several tests sh.wed th.t 'least variance' h.s many advantages. First, it is less sensitive to noises. Second, it operates well in small sample size. Th.rd, it depends less on th. sampling position.

关键词： multiangular remote sensing BRDF model inversion global albedo.

Ph.sician disruptive beh.viors: Five year progress report

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World Journal of Clinical Cases 2015年第11期3卷 930-934页

作者： alan h.Rosenstein Independent Practitioner Internal Medicine

Disruptive beh.viors in h.alth.care can h.ve a significant adverse effect on staff interactions th.t can negatively impact staff satisfaction, staff performance, and patient outcomes of care. As referenced in a previously publish.d article, th. Obstetrics and Gynecology specialty is one of th. service areas wh.re th.se beh.viors occur more frequently. Despite growing evidence of th. ill effects of th.se types ofbeh.viors many organizations are still h.ving a difficult time in addressing th.se issues in an effective manner. Gaining a better understanding of th. nature, causes, and impact of th.se beh.viors is crucial to finding th. righ. remedies for solution. Nobody intentionally starts th. day planning to be disruptive, it's just th.t th.ngs get in th. way. A combination of deep seated factors related to age and gender preferences, culture and eth.icity, life experiences, and oth.r events th.t h.lp sh.pe values, attitudes and personalities, and more external factors related to training, environmental pressures, stress and burnout, and oth.r personal issues all contribute to th. mix. Given th. complexities of today's h.alth.care environment, each.person needs to recognize th. importance of being h.ld accountable for appropriate actions and beh.viors th.t affect work relationsh.ps and care coordination th.t impact patient care. Early recognition, early intervention, and taking a pro-active supportive approach.to improve individual beh.viors will result in better relationsh.ps, less disruption, more satisfaction, and better outcomes of care.

关键词： Disruptive beh.viors Patient safety Patient outcomes Staff relationsh.ps Communication Teamwork

Apparent reciprocity failure in directional reflectance of structured surfaces

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Progress in Natural Science:Materials International 1999年第10期9卷 28-33页

作者：李小文,王锦地,alan h.STRAh.ER Research.Center for Remote Sensing Beijing Normal University Beijing 100875 Ch.na Center for Remote Sensing and Department of Geograph. Boston University MA 02215 USA Research.Center for Remote Sensing Beijing Normal University Beijing 100875 Ch.na Center for Remote Sensing and Department of Geograph. Boston University MA 02215 USA

Wh.th.r th. reciprocity principle can be applied to th. field or satellite observations of directional reflectance of land surface h.s been a question important to both.th.ory and practice of land surface remote sensing. Under th. assumption th.t every point on ground follows reciprocity, th.s paper explains wh. th. h.terogeneity of land surface can still yield apparent failure of th. principle at th. scale of remote sensing pixel.

关键词： reciprocity structure BRDF

Teach.ng global climate ch.nge

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Natural Science 2013年第1期5卷 120-123页

作者： alan h. McGowan Environmental Studies Program The New School New York USA

Alth.ugh.th.re is strong consensus among scientists th.t global climate ch.nge is real and dangerous, and th.re is increasing belief of th.s among th. general public, th.re still remains a significant gap between scientific opinion and th.t of th. public. Th. academic environmental community, th.refore, h.s a clear opportunity and responsibility to teach.th. facts of global climate ch.nge, particularly to non-environmental majors, th.se people wh. are th. voters of th. future. Th. article presents several ideas along th.se lines, and calls for a revitalized effort to teach.climate ch.nge to undergraduate students.

关键词： Climate Ch.nge Environment Education Undergraduate General Education

Circulation Ch.racteristics of Persistent Cold Spells in Central–Eastern North.America

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Journal of Meteorological Research 2017年第1期31卷 250-260页

作者： Zh.nh.a LI alan h. MANSON Yanping LI Ch.is MEEK Institute of Space and Atmosph.ric Studies Department of Physics and Engineering Physics University of Saskatchewan 116 Science Place Saskatoon Saskatchewan S7N 5E2 Canada Global Institute for Water Security University of Saskatchewan 11 Innovation Boulevard Saskatoon Saskatchewan S7N3H5 Canada

Th. circulation patterns of persistent cold weath.r spells with.durations longer th.n 10 days in central-eastern North.America （United States and Canada; 32° 52°N, 95°-65°W） are investigated by using NCEP reanalysis data from 1948 to 2014. Th. criteria for th. persistent cold spells are：（1） th.ee-day averaged temperature anomalies for th. regional average over th. central-eastern United States and Canada must be below th. 10th.percentile, and （2） such.extreme cold spells must last at least 10 days. Th. circulation patterns associated with.th.se cold spells are ex- amined to find th. common signals of th.se events. Th. circulation anomaly patterns of th.se cold spells are categor- ized based on th. E1 Nifio--South.rn Oscillation, Arctic Oscillation （AO）, and oth.r climate indices. Th. atmosph.ric circulation patterns th.t favor th. cold spells are identified th.ough.composites of geopotential h.igh. maps for th. cold spells. Negative AO ph.ses favor persistent cold spells. Ph.ses of sea surface temperature （SST） modes th.t are associated with.warm SSTs in th. eastern extratropical Pacific also favor persistent cold events in th. study region. Stratosph.ric polar vortex breakdown alone is not a good predictor for th. regional extreme cold spells in central-eastern North.America. Th. meridional dispersions of quasi-stationary Rossby waves in th. Pacific-North.America sector in terms of cut-off zonal wavenumber modulated by background flow are analyzed to provide insigh. into th. difference in evolution of th. cold spells under different mean AO ph.ses. Th. waveguide for AO 〉 1 is in a narrow latitudinal band centered on 40°N, wh.reas th. waveguide for AO 〈 -1 is in a broader latitudinal band from 40° to 65°N. Th. circulation patterns and lower boundary conditions favorable for persistent cold spells identified by th.s study can be a stepping-stone for improving winter subseasonal forecasting in North.America.

关键词： cold spell quasi-stationary Rossby wave ENSO Arctic Oscillation

A h.brid geometric optical-radiative transfer approach.for modeling ligh. absorption and albedo of discontinuous canopies

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Science Ch.na Ch.mistry 1995年第7期38卷 807-816页

作者：李小文王锦地 alan h.Strah.er Institute of Remote Seining Application Chinese Academy of SciencesBeijing 100101China Centre of Remote Sensing Boston UniversityBoston MA02215USA

A new model for ligh.-absorption and alh.do of a vegetation cover combines principles of geometric optics and radiative *** relies on th. gap probabilities and path.length.distributions to model th. penetration of th. irradiance from a parailel source and th. single and multiple scattering of th.t irradi- *** model is applied to th. vegetation covers of th. discrete plant crowns th.t are randomly centred both.on th. plane and with.n a layer of variable th.ckness(from h.1 to h.2)above *** assume a sph.roi- dal sh.pe with.an arbitrary h.igh. to width.ratio(B/R).Geometric optics easily models th. irradianee th.t penetrates th. vegetation cover directly,and is scattered by th. soil,and exist with.ut furth.r scattering by th. *** a plant crown,th. probability of scattering is a negative exponential function of path.*** crown scattering provides th. source for th. singly scattered radiation,wh.ch.provides th. source for double scattering,and th.n h.gh.r order pairs of scattering are solved successively by a convolution- like *** validations using data from a conifer stand near h.wland,Maine of USA sh.w reasonable agreement between th. modeled and observed albedo.

关键词： absorption albedo discontinuous canopy geometric optics radiative transfer.