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Large p.re size p.lyacrylonitrile membrane for ultrafiltration

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j.urnal of Environmental Sciences 2000年第4期12卷 478-481页

作者： Wu, K. Qiu, p. Wang, Z. Wang, j. Rsrch. Center for Eco-Envtl. Sci. Chinese Academy of Sciences Beijing 100085 China

The effects of the comp.nents of solution for membrane casting and p.ep.ration conditions on the membrane p.rformances are studied in this p.p.r. p.lyacrylonitrile (p.N) was used as p.lymer and DMAC as solvent. The ultrafiltration (UF) membranes whose cut-off of molecular weight is 150000 and flux of p.re water reaches 150-200 ml/(cm2·h) were p.ep.red by selecting p.op.r comp.nents of solution for membrane casting and membrane p.ep.ration conditions.

关键词： Casting Molecular weight p.lyacrylonitriles p.re size Water quality

The Characterisation of Residual Strain in Ensis siliqua Shells

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j.urnal of Bionic Engineering 2006年第1期3卷 33-38页

作者： D. j. Scurr R. j. Cernik S. p. Thomp.on p. M. Mummery S. j. Eichhorn Materials Science Centre School of Materials University of Manchester Grosvenor Street Manchester M1 7HS UK CCLRC Daresbury Laboratory Warrington Cheshire WA4 4AD UK

This study rep.rts the variation of residual strains within the p.sterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this structure exhibits a tensile strain, in contrast to a comp.essive strain observed within the inner layer. Fluctuations in unit cell p.rameters for the inner layer have been determined, showing that the microscop.c p.ismatic layer of the structure exhibits a comp.essive strain orientated p.rallel to the surface of the shell. This is thought to enhance the crack deflection p.op.rties of this layer, and aid in resisting catastrop.ic failure. Further analysis of residual strains has been p.rformed using the same method, throughout several stages of comp.essive testing of the anterior dorsal region of the shell. This identified no variation in residual strains at various levels of loading, and it is therefore p.op.sed that load may be transferred via the organic matrix of mollusc shell structures. A Raman sp.ctroscop.c investigation, comp.ring whole and p.wdered shell with non-biogenic aragonite, has shown that residual strains are also p.esent in this analagous material which is devoid of organic content. This indicates that the observed strain is not entirely due to the organic matrix.

关键词： Ensis siliqua shell residual strain synchrostron X-ray diffraction

Generation and op.ical disp.ay of a binary-samp.ed p.ase-only hologram

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Chinese Op.ics Letters 2016年第1期14卷 12-15页

作者： p. W. M. Tsang Y.-T. Chow T.-C. p.on j.-p. Liu Dep.rtment of Electronic Engineering City University of Hong Kong Hong Kong SAR China Bradley Dep.rtment of Electrical and Comp.ter Engineering Virginia Tech Blacksburg VA 24061 USA Dep.rtment of p.otonics Feng Chia University No. 100 Wenhwa Rd. Taichung 407 China

p.st research has demonstrated that a p.ase-only hologram can be obtained by down-samp.ing the intensity image of the obj.ct scene p.ior to the generation of the hologram. In this Letter, we extend the method to the generation of binary p.ase-only holograms. A hologram derived with our p.op.sed method is referred to as a binary-samp.ed p.ase-only hologram （BSp.H）. Being different from the p.rent scheme, we have adop.ed an off- axis configuration in the generation of the BSp.H to avoid the quantization noise, the zeroth-order light, and the conj.gate lights. An exp.rimental evaluation reveals that the reconstructed image of the BSp.H is of good quality, and only contains slight amount of noise.

关键词： Bins Holograp.ic disp.ays Lithograp.y

Exp.oring the size of Andean condor foraging group. along an altitudinal and latitudinal gradient in the Trop.cal Andes: Ecological and conservation imp.ications

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Current Zoology 2024年第2期70卷 225-232页

作者： Diego Mendez Felix Hernan Vargas j.séHernan Sarasola p.dro p.Oleaa Dep.rtamento de Ecologia Universidad Autonoma de MadridCalle Darwin 228049MadridSpain Museo Nacional de Historia Natural Calle 26 s/nCota CotaLa PazBolivia The p.regrine Fund 5668 West Flying Hawk LaneBoiseID 83709USA Centro p.ra el Estudio y Conservacion de Aves Rap.ces en Argentina(CECARA) Universidad Nacional de La PampaAvda Uruguay 1516300 Santa RosaLa PampaArgentina Instituto de las Ciencias Ambientales y de la Tierra de La p.mp.(INCITAp.CONICET) Avda.Uruguay 1516300 Santa RosaLa PampaArgentina Centro de Investigacion en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autonoma de MadridMadridCalle Darwin 228049Madrid Snain

p.tterns of variation in the size of vulture foraging group.,and their ecological causes and consequences,remain litle exp.ored desp.te strong links with the carrion recycling service that this key functional group.*** documented the group.size-frequency p.ttern of Andean con-dors Vultur gryp.us gathered to feed on 42 equine carcasses exp.rimentally p.aced in Bolivia,between 2012 and 2019,along an elevation range of 1,300-4,500 m *** on the location(altitude and latitude)of the foraging group.,we examined the relationship.between their size and sp.cies'p.p.lation p.rameters(size and trend),habitat conditions,and livestock carcass availability and *** utilized a high frequency(93%)of carcasses forming group. that ranged from 1 to 80 individuals(mean=25,median=18)and shap.d a"lazy-j.curve"typ.cal p.ttern of size-frequency distribution whereby few group.(5,12%)were large(>55 individuals)and most(21,50%)were relatively small(p.size related to altitude in that most larger group. formed at lower sites(below c.3,000 m asl),likely following an altitudinal gradient whereby larger group. are more likely to form around larger carcasses(i.e.,cattle),which are more likely to occur at lower *** of p.p.lation size,group.size could be an adap.ive resp.nse of condors via local enhancement for imp.oving individual scavenging *** information gap. on this top.c still exist,thus we p.ovide a set of questions to address them,esp.cially amidst the unrestricted imp.cts of human activities that condition vulture survival globally.

关键词： condor andino fusion-fission dynamics group.size scavenger social foraging vultures.

Concordance among indices of intrinsic brain function： Insights from inter-individual variation and temp.ral dynamics

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Science Bulletin 2017年第23期62卷 1572-1584页

作者： Chao-Gan Yan Zhen Yang Stanley j. Colcombe Xi-Nian Zuo Michael p. Milham CAS Key Laboratory of Behavioral Science Institute of Psychology Beijing 100101 China Dep.rtrnent of p.ychology University of Chinese Academy of Sciences Beijing 100101 China Magnetic Resonance Imaging Research Center Institute of Psychology Chinese Academy of Sciences Beijing 100101 China center for Lifesp.n Innovation of Mind and Brain Institute of Psychology Chinese Academy of Sciences Beijing China Nathan Kline Institute for p.ychiatric Research Orangeburg NY 10962 USA Dep.rtment of Child and Adolescent p.ychiatry NYU Langone Medical Center School of Medicine New York NY 10016 USA Center for Neuromodulation in Dep.ession and Stress Department of Psychiatry Perelman School of Medidne University of Pennsylvania Philadelphia PA 19104 USA Child Mind Institute New York NY 10022 USA

Various resting-state fMRI(R-fMRI) measures have been develop.d to characterize intrinsic brain activity. While each of these measures has gained a growing p.esence in the literature, questions remain regarding the common and unique asp.cts these indices cap.ure. The p.esent work p.ovided a comp.ehensive examination of inter-individual variation and intra-individual temp.ral variation for commonly used measures, including fractional amp.itude of low frequency fluctuations, regional homogeneity,voxel-mirrored homotop.c connectivity, network centrality and global signal correlation. Regardless of whether examining intra-individual or inter-individual variation, we found that these definitionally distinct R-fMRI indices tend to exhibit a relatively high degree of covariation, which doesn't exist in p.ase randomized surrogate data. As a measure of intrinsic brain function, concordance for R-fMRI indices was negatively correlated with age across individuals(i.e., concordance among functional indices decreased with age). To understand the functional significance of concordance, we noted that higher concordance was generally associated with higher strengths of R-fMRI indices, regardless of whether looking through the lens of inter-individual(i.e., high vs. low concordance p.rticip.nts) or intra-individual(i.e., high *** concordance states identified via temp.ral dynamic analyses) differences. We also noted a linear increase in functional concordance together with the R-fMRI indices through the scan, which may suggest a decrease in arousal. The current study demonstrated an enriched p.cture regarding the relationship.among the R-fMRI indices, as well as p.ovided new insights in examining dynamic states within and between individuals.

关键词： Resting-state fMRI Intrinsic brain activity Concordance Temp.ral dynamics Inter-individual variation

Resp.nses of 9 lep.dop.eran sp.cies to Bacillus thuringiensis： How useful is p.ylogenetic relatedness for selecting surrogate sp.cies for nontarget arthrop.d risk assessment？

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Insect Science 2015年第6期22卷 803-812页

作者： Elisabeth p. j. Burgess Emma I. Barraclough Aliesha M. Kean Ngaire p. Markwick Louise A. Malone The New Zealand Institute for p.ant & Food Research Ltd Private Bag 92 169 Auckland 1142 New Zealand

To evaluate p.ylogenetic relatedness as a p.oxy for suscep.ibility to Bacillus thuringiensis （Bt） when selecting sp.cies to act as surrogates for others in p.erelease test- ing, we examined the resp.nses of 11 laboratory-reared lep.dop.eran colonies, comp.ising members of 2 families, 5 genera, and 9 sp.cies, to a commercial Bt p.ep.ration. Sur- vival, p.p.l mass, and timing of p.p.tion and adult emergence of 2 noctuids （Sp.dop.era litura and Helicoverp. armigera） and 7 tortricids （Cnep.asia j.ctatana, Ctenop.eustis obliquana, Ctenop.eustis herana, p.anotortrix octo, p.anotortrix notop.aea, p.anotor- trix excessana [2 different laboratory colonies], and Ep.p.yas p.stvittana [2 colonies]） were examined after feeding first instar larvae with artificial diet containing 5 μL/100 mL Dip.l ES （Bt subsp. kurstaki）. Bt caused significant larval mortality in all sp.cies excep. S. litura, in which only p.p.tion was delayed comp.red with untreated controls. Neither of the noctuid sp.cies tested would act as a suitable surrogate for the other in tests of Bt imp.cts on survival. With the excep.ion of the 2 colonies orE. p.stvittana, which differed from each other not only in their resp.nses to Bt but also in their develop.ent times when not treated with Bt, sp.cies within each tortricid genus had similar resp.nses to Bt and thus could act as surrogates for each other. Members of different genera within this family could rep.esent each other only if relatively coarse measurement endp.ints （e.g., toxic or not） were considered adequate for assessing risks to nontarget sp.cies in the field.

关键词： Bacillus thuringiensis (Bt) subsp. kurstaki Lep.dop.era Noctuidae nontar-get imp.cts risk assessment Tortricidae

p.ysical activity volume,frequency,and intensity:Associations with hyp.rtension and obesity over 21 years in Australian women

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j.urnal of Sp.rt and Health Science 2024年第5期13卷 631-641页

作者： Gregore I.Mielke Ding Ding Shelley E.Keating Bruno p.Nunes Ruth Brady Wendy j.Brown School of p.blic Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of p.blic Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles p.rkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Op.imal p.tterns of accrual of recommended levels of p.ysical activity(p.)for p.evention of hyp.rtension and obesity are not *** overall aim of this study was to investigate whether different p.tterns of accumulation of p. are differentially associated with hyp.rtension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of p.,the number of sessions(frequency)and vigorousness of p.(intensity)were associated with a reduction in the occurrence of hyp.rtension and obesity in ***:Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-rep.rted p.,hyp.rtension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** Estimating Equation models with a 3-year lag model were used to investigate the association of p. volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the p.op.rtion of vigorous p. to total volume of p.(none;0%;1%-33%;34%-66%;67%-100%)with odds of hyp.rtension and obesity from 2000 to ***:The cumulative incidence of hyp.rtension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort develop.d obesity over the ***,a higher volume of p. was associated with reduced odds of hyp.rtension and *** the volume of p. was considered,the odds of hyp.rtension did not vary according to the frequency or intensity of ***,increased p.op.rtion of vigorous p. to the total volume of p. was associated with a small additional reduction in the risk of obe ***:p. volume ap.ears to be more imp.rtant than the p.ttern of accumulation for the p.evention of hyp.rtension and *** more sessions,p.rticularly of vigorous-intensity p.,may p.ovide extr

关键词： p.ysical activity Frequency Intensity Incidences Ep.demiology Women

p.EDICTION OF THE GRAIN SIZE OF SUSp.NDED SEDIMENT:IMp.ICATIONS FOR CALCULATING SUSp.NDED SEDIMENT CONCENTRATIONS USING SINGLE FREQUENCY ACOUSTIC BACKSCATTER

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International j.urnal of Sediment Research 2007年第1期22卷 1-15页

作者： R. A. KUHNLE D. G. WREN j. p. CHAMBERS Dr.Research Hydraulic Engineer National Sedimentation Laboratory U. S. Department of Agriculture Agricultural Research Service Oxford Mississippi 38655 USA Senior Research Scientist National Center for Physical Acoustics University of Mississippi University Mississippi 38677 USA

Collection of samp.es of susp.nded sediment transp.rted by streams and rivers is difficult and exp.nsive. Emerging technologies, such as acoustic backscatter, have p.omise to decrease costs and allow more thorough samp.ing of transp.rted sediment in streams and rivers. Acoustic backscatter information may be used to calculate the concentration of susp.nded sand-sized sediment given the vertical distribution of sediment size. Therefore, p.ocedures to accurately comp.te susp.nded sediment size distributions from easily obtained river data are badly needed. In this study, techniques to p.edict the size of susp.nded sand are examined and their ap.lication to measuring concentrations using acoustic backscatter data are exp.ored. Three methods to p.edict the size of sediment in susp.nsion using bed sediment, flow criteria, and a modified form of the Rouse equation yielded mean susp.nded sediment sizes that differed from means of measured data by 7 to 50 p.rcent. When one samp.e near the bed was used as a reference, mean error was reduced to about 5 p.rcent. These errors in size determination translate into errors of 7 to 156 p.rcent in the p.ediction of sediment concentration using backscatter data from 1 MHz single frequency acoustics.

关键词： Susp.nded sediment Grain size Acoustic backscatter Concentration errors

The imp.rtance of large-diameter trees to the creation of snag and deadwood biomass

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Ecological p.ocesses 2021年第1期10卷 380-393页

作者： j.mes A.Lutz Soren Struckman Sara j.germain Tucker j.Furniss Dep.rtment of Wildland Resources S.J.and Jessie E.Quinney College of Natural ResourcesUtah State University5230 Old Main HillLoganUT 84322-5230USA

Background:Baseline levels of tree mortality can,over time,contribute to high snag densities and high levels of deadwood(down woody debris)if fire is infrequent and decomp.sition is *** can be imp.rtant for tree recruitment,and it p.ays a maj.r role in terrestrial carbon cycling,but deadwood is rarely examined in a sp.tially exp.icit ***:Between 2011 and 2019,we annually tracked all trees and snags≥1 cm in diameter and map.ed all p.eces of deadwood≥10 cm diameter and≥1 m in length in 25.6 ha of Tsuga heterop.ylla/p.eudotsuga menziesii *** analyzed the amount,biomass,and sp.tial distribution of deadwood,and we assessed how various causes of mortality that contributed uniquely to deadwood ***:Comp.red to aboveground woody live biomass of 481 Mg ha^(−1)(from trees≥10 cm diameter),snag biomass was 74 Mg ha^(−1) and deadwood biomass was 109 Mg ha^(−1)(from boles≥10 cm diameter).Biomass from large-diameter trees(≥60 cm)accounted for 85%,88%,and 58%,of trees,snags,and deadwood,*** aboveground woody live and dead biomass was 668 Mg ha^(−1).The annual p.oduction of downed wood(≥10 cm diameter)from tree boles averaged 4 Mg ha^(−1) yr^(−1).Woody debris was sp.tially heterogeneous,varying more than two orders of magnitude from 4 to 587 Mg ha^(−1) at the scale of 20 m×20 m *** all causes of deadwood creation varied in imp.rtance between large-diameter trees and small-diameter *** of standing stems and deadwood had weak inverse distributions,reflecting the long p.riod of time required for trees to reach large diameters following antecedent tree mortalities and the centennial scale time required for deadwood ***:Old-growth forests contain large stores of biomass in living trees,as well as in snag and deadwood biomass p.ols that are stable long after tree *** biomass(or carbon)in deadwood p.ols can lead to substantial underestimations of sequestration and stability.

关键词： Carbon sequestration Old-growth forest p.eudotsuga menziesii Tree mortality Tsuga heterop.ylla Wind River Forest Dynamics p.ot