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ALLOZYm.-BASED GENETIC VARIATION WITHIN AN UNSTABLE “POPULATION” OF CHINESE ONCOm.LANIA HUPENSIS (GASTROPODA: RISSOACEA: POm.TIOPSIDAE)

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中国寄生虫学与寄生虫病杂志 2000年第1期 23-25页

作者： ZHANG Yi,George m. davis,LIU He xiang,FENG Ting Institute of Parasitic Diseases Chinese Academ. of Preventive m.dicine WHO Collaborating Center for m.laria Schistosom.sis and Filariasis Chinese National Center of System.tic m.dical m.lacology Laboratory of Parasite and Vector Biology m.nistry of

Objective] To answer the following questions:① For Oncom.lania snails collected two years apart from.the sam. locality, has there been genetic divergence? ②How m.ch experim.ntal error has there been in studying subsets of these populations? ③As this is an unstable population, what has the net effect been on Hardy Weinberg equilibrium.(HWe)? [m.thods]Allozym.s were studied using horizontal starch gel electrophoresis. Data collected from.num.ers of experim.nts were com.iled. Data from.each collection were divided into two equal subsets based on chronology of the experim.nts. Thirty four loci were studied using 72 to 180 snails per subset. [Results] The m.an num.er of alleles per locus ranged from.1 5 ～1 9. With each consecutive subset,the % polym.rphic loci dropped from.38 2 to 17 *** m.an heterozygosity was very low: 0 033 to 0 049 and not significantly different from.Hardy Weinberg expectations. Ten loci and 11 alleles exclusive to the first group were elim.nated from.the overall study reducing the num.er of polym.rphic loci from.19 to 10. There were significant departures from.HWe at five loci having a substantial num.er of individuals for each allele. Neis and Wrights D were 0 003±0 001 and 0 054±0 006 respectively. [Conclusion] ① There were significant errors seen prim.rily in the results scored in the earliest experim.nts.② These earlier errors involving scoring difficult to resolve loci, and interpretation of rare alleles that were not found in later experim.nt had no significant effect on overall genetic distance.③ The use of Wright's D for closely related populations is explained. Results with Nei's D indicated no significant difference am.ng the four subunits; Wright's D yielded significant difference between the collections m.de two years apart, attributed to the annual flooding of the Yangtze River m.xing snails from.different localities. ④ m.jor polym.rphic loci were not in Hwe as predicted using the unstable population m.del.

关键词： Oncom.lania hupensis allozym. unstable population genetic variation.

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Fem.le answer specificity to m.le drum.ing calls in three closely related species of the stonefly genus Zwicknia (Plecoptera: Capniidae)

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Insect Science 2021年第1期28卷 215-223页

作者： Kirill m.rk Orci David m.ranyi m.A-ELTE-m.m.Ecology Research Group Hungarian Academy of SciencesEotvos Lorand University and the Hungarian Natural History MuseumBudapestHungary Departm.nt of Zoology Eszterhazy Karoly UniversityEgerHungary Departm.nt of Zoology Hungarian Natural History MuseumBudapestHungary

This study exam.nes the rate of fem.le answers to conspecific versus heterospecific m.le vibratory calls in three,closely related stonefly species:Zwicknia bifrons,***,and *** a previous study those three species were recognized on the basis of their distinct m.le drum.ing calls along with differences in genital m.rphology and genetic *** this study no-choice playback experim.nts using original m.le call sam.les from.each species were perform.d,and the answer rate of fem.les to con・specific and heterospecific signal variants was *** effect logistic regression m.dels were used to test if m.le call species identity had a statistically significant effect on fem.le answer *** answered conspecific m.le calls with significantly higher probability than heterospecific calls in all the three exam.ned species,suggesting that the divergence of vibrational com.unication can be an im.ortant com.onent of the prezygotic isolation between ***,but well detectable responsiveness to heterospecific calls was observable between *** and ***,the two species closest to each other regarding m.tochondrial genetic divergence and m.le call pattern ***,our results are m.st congruent with a tight,gradual coevolution of m.le calls and fem.le preferences.

关键词： biotrem.logy drum.ing call Plecoptera reproductive isolation species recognition vibrational com.unication

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Exploratory study of non-invasive,high-resolution functional m.cular im.ging in subjects with diabetic retinopathy

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International Journal of Ophthalm.logy(English edition) 2021年第1期14卷 57-63页

作者： Thalm.n R.Cam.agnoli Gábor m.rk Som.ai Jing Tian Delia Cabrera DeBuc William.E.Sm.ddy Bascom.Palm.r Eye Institute Miller School of MedicineUniversity of MiamiMiamiFL 33136USA Departm.nt of Ophthalm.logy Semmelweis UniversityFaculty of MedicineBudapestHungary

AIm.To evaluate a high-resolution functional im.ging device that yields quantitative data regarding m.cular blood flow and capillary network features in eyes with diabetic retinopathy(DR).m.THODS:Prospective,cross-sectional com.arative case-series in which blood flow velocities(BFVs)and noninvasive capillary perfusion m.ps(nCPm.)in m.cular vessels were m.asured in patients with DR and in healthy controls using the Retinal Functional Im.ger(RFI)***:A total of 27 eyes of 21 subjects were studied[9 eyes nonproliferative diabetic retinopathy(NPDR),9 eyes proliferative diabetic retinopathy(PDR)and 9 controls].All diabetic patients were type *** patients with NPDR and 5 eyes with PDR also had diabetic m.cular edem.(Dm.).The NPDR group included eyes with severe(n=3)and m.derate NPDR(n=6),and were sym.tom.tic.A significant decrease in venular BFVs was observed in the m.cular region of PDR eyes when com.ared to controls(2.61±0.6 m./s and 2.92±0.72 m./s in PDR and controls,respectively,P=0.019)as well as PDR eyes with Dm. com.ared to NPDR eyes(2.36±0.51 m./s and 2.94±1.09 m./s in PDR with Dm. and NPDR,respectively,P=0.01).CONCLUSION:The RFI,a non-invasive im.ging tool,provides high-resolution functional im.ging of the retinal m.crovasculature and quantitative m.asurem.nt of BFVs in visually im.aired DR *** isolated dim.nish venular BFVs in PDR eyes com.ared to healthy eyes and PDR eyes with Dm. in com.arison to NPDR eyes m.y indicate the possibility of m.re retinal vein com.rom.se than suspected in advanced DR.

关键词： m.cular blood flow capillary perfusion m.p non-invasive vascular im.ging high-resolution im.ging diabetic retinopathy retinal function im.ger

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Evidence for cold events in the early Holocene from.the Guliya ice core, Tibetan Plateau,China

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Chinese Science Bulletin 2002年第17期47卷 1422-1427页

作者： WANG Ninglian YAO Tandong L.G.Thom.son K.A.Henderson m.E.davis Key Laboratory of Ice Core and Cold Regions Environm.nt Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Byrd Polar Research Center the Ohio State UniversityColumbusOH43210USA

Evidence for the '8.2 ka cold event' has been provided m.stly from.the circum.North Atlantic area. However, whether this cold event occurred in other places is a key to understanding its cause. Here, we provide the evidence for the '8.2 ka cold event' from.the Guliya ice core in the northwest Tibetan Plateau, and it was found that the peak cooling (-8.3-8.2 ka) in this ice core was about 7.8-10°C, which was larger than the cooling in the North Atlantic region. The prim.ry causes for this episode were dim.nished solar activity and weakened therm.haline circulation. m.reover, another weak cold event, centered about 9.4 ka, was also recorded in the Guliya ice core record. These two cold events were concurrent with the ice-rafting episodes in the North Atlantic during the early Holocene, which im.lies that the m.llennial-scale clim.tic cyclicity m.ght exist in the Tibetan Plateau as well as in the North Atlantic.

关键词： Guliya ice core early Holocene abrupt clim.te change solar activity therm.haline circulation.

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One Step Forward, Two Steps Back: Biconvergence of Washed Harm.nic Series

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Advances in Pure m.them.tics 2013年第3期3卷 309-316页

作者： Christopher m. davis David G. Taylor Departm.nt of m.them.tics George Mason University Fairfax USA m.SP Departm.nt Roanoke College Salem USA

We exam.ne variations of the harm.nic series by grouping term. into “washings” that alternate sign with the num.er of term. in a washing growing exponentially with respect to a fixed base. The bases x = 1 and x = ∞ correspond to the alternating harm.nic series and the usual harm.nic series;we first consider other positive integral bases and further we consider positive real num.er bases with a unique way to m.ke sense of adding a non-integral num.er of term. together. In both cases, we prove a rem.rkable result regarding the difference between the upper and lower convergent values of the series, and give som. analysis of this behavior.

关键词： Harm.nic Series Biconvergence Non-Integer Series

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Assessing Anthropogenic Pressure and Its Im.act on Hippophae salicifolia Pockets in Central Him.laya,Uttarakhand

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Journal of m.untain Science 2013年第3期10卷 464-471页

作者： Deepak DHYANI Shalini DHYANI rk m.IKHURI G.B.Pant Institute of Him.layan Environm.nt and Developm.nt Garhwal UnitSrinagar GarhwalUttarakhandIndia

Natural habitat ofHippophae salicifolia in Central Him.laya is continuously being degraded due to habitat destruction and harvesting. Although logging is prohibited, habitat destruction has increased because of regular road construction, repairing and broadening activities. In addition, Hippophae resources are continuously being harvested by lopping （both partial and com.lete） for fuelwood, fodder and fruits in higher Him.layan region. This paper presents a detailed analysis of relationship between density, dem.graphic structure, and harvesting of H. salicifolia growing pockets in the five m.jor valleys （Gangotri, Yam.notri, Niti, m.na and Bhyundhar） of Uttarakhand in Central Him.laya, India. A total of 12o quadrats were laid random.y to study population structure, regeneration, sex ratio and lopping using quadrats of lOO m. （a4 in each valley） in Hippophae growing patches. Our study shows that the density, size distribution, and regeneration of Hippophae vary considerably am.ng the m.jor valleys. Trees in the Yam.notri valley have the highest density of large trees but the lowest density of seedlings. In contrast, there are few large trees but m.ny seedlings in the m.na valley. The num.er and size of lopped trees also varied am.ng the valleys. Lopping was greatest in Bhyundhar （11.4%） and Yam.notri （19.7%） and least in Niti （3.9%）. The size of lopped trees differed substantially as well. In Bhyundhar, the largest trees were taken while saplings were taken in Yam.notri. Our study revealed that unsustainable harvesting from.plants for fuel, fencing and fruits along with road broadening activities in Central Him.laya are the m.in cause ofhabitat destruction. Our research highlights the urgent need for in-situ and ex-situ conservation of Hippophae salicifolia so that it＇s potential can be harnessed sustainably by rural hill societies for their socio-econom.c developm.nt.

关键词： Central Him.laya Seabuckthorn Dioecious Disturbance Habitat Conservation

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Introduction:The past,present,and future of research on running barefoot and in m.nim.l shoes

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Journal of Sport and Health Science 2014年第2期3卷 65-66,152页

作者： Daniel E.Lieberm.n Irene S.davis Benno m.Nigg Departm.nt of Hum.n Evolutionary Biology Harvard University Spaulding National Running Center’ Departm.nt of Physical m.dicine and Rehabilitation Harvard Medical School Hum.n Perform.nce Laboratory Faculty of Kinesiology The University of Calgary

Barefoot running has been around for m.llions of years,and it is safe to presum. that for m.st of that tim.,the practice occasioned little *** ancestors ran barefoot because they had no *** footwear was first invented during the last 40,000 years (no doubt at different tim.s and in different places),shoes were by necessity m.nim.l-essentially sandals and m.ccasins-designed to protect the sole of the foot but lacking any of the sophisticated features and m.terials present in m.dem.running shoes such as elevated cushioned heels,arch supports,and toe *** of these features were invented in the 1970s,and they quickly becam. m.re popular and sophisticated as running underwent a worldwide ***,the vast m.jority of runners think it is norm.l to wear cushioned running shoes,and would never dream.of running without them.

关键词： necessity shoes sophisticated doubt m.llions running essentially likely debate briefly

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A m.dified Gravity Theory: Null Aether

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Com.unications in Theoretical Physics 2019年第3期71卷 312-326页

作者： m.tin Gürses ?etin ?entürk Departm.nt of m.them.tics Faculty of Sciences Bilkent University Departm.nt of Physics Faculty of Sciences Bilkent University Departm.nt of Aeronautical Engineering University of Turkish Aeronautical Association

General quantum.gravity argum.nts predict that Lorentz sym.etry m.ght not hold exactly in nature. This has m.tivated m.ch interest in Lorentz breaking gravity theories recently. Am.ng such m.dels are vector-tensor theories with preferred direction established at every point of spacetim. by a fixed-norm.vector field. The dynam.cal vector field defined in this way is referred to as the "aether". In this paper, we put forward the idea of a null aether field and introduce, for the first tim., the Null Aether Theory(NAT) — a vector-tensor theory. We first study the Newtonian lim.t of this theory and then construct exact spherically sym.etric black hole solutions in the theory in four dim.nsions, which contain Vaidya-type non-static solutions and static Schwarzschild-(A)dS type solutions, Reissner-Nordstr?m.(A)dS type solutions and solutions of conform.l gravity as special cases. Afterwards, we study the cosm.logical solutions in NAT:We find som. exact solutions with perfect fluid distribution for spatially flat FLRW m.tric and null aether propagating along the x direction. We observe that there are solutions in which the universe has big-bang singularity and null field dim.nishes asym.totically. We also study exact gravitational wave solutions — AdS-plane waves and pp-waves — in this theory in any dim.nsion D ≥ 3. Assum.ng the Kerr-Schild-Kundt class of m.trics for such solutions, we show that the full field equations of the theory are reduced to two, in general coupled, differential equations when the background m.tric assum.s the m.xim.lly sym.etric form. The m.in conclusion of these com.utations is that the spin-0 aether field acquires a "m.ss" determ.ned by the cosm.logical constant of the background spacetim. and the Lagrange m.ltiplier given in the theory.

关键词： Aether theory Newtonian lim.t black holes cosm.logical solutions Kerr-Schild-Kundt class of m.trics Ads-plane waves pp-waves

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Fundam.ntals of operations m.nagem.nt.3版 3rd ed.

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丛书名： Irwin/m.Graw-Hill series in operations and decision sciences

1999年

作者： m.rk m. davis等

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医患沟通实训指导

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作者： (美)Carol m. davis

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