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Journal of.Water Resource and Protection 2023年第9期15卷 299-314页

作者： Nancy J. Leland Kimberley Crocker Pearson Marty K. Burke Jef.rey T. Miller Alison Watts james f. haney Department of.Biological Sciences University of New Hampshire Center for Freshwater Biology and Ecotoxicology Durham New Hampshire USA Lim-Tex North Andover Massachusetts USA Brewster Natural Resources Advisory Commission Brewster Massachusetts USA Brewster Ponds Coalition Brewster Massachusetts USA Department of.Civil and Environmental Engineering University of New Hampshire College of Engineering and Physical Sciences Durham New Hampshire USA

We have verif.ed the use of.a serial f.ltration method to isolate picocyanobacteria f.r analysis. We used eDNA metabarcoding to conf.rm the picocyanobacteria as members of.the Order Synechococcales, Genus Cyanobium, specif.cally Cyanobium 6307. f.uorometric analysis using accessory pigments phycocyanin and phycoerythrin described periods of.excess biomass, where the net growth rate model conf.rmed these conditions. The total anatoxin-a concentrations in the picocyanobacterial sample ranged f.om 0.0074 - 6.41 μg·L-1 representing a 40-f.ld dif.erence over the entire sampling season. Sampling f.equency of.every three days appeared to be an important f.ctor in capturing these changes in anatoxin-a concentration. During a period of.excess biomass, we were able to establish a linear correlation between cyanobacterial biomass and Anatoxin-a concentrations.

关键词： Picocyanobacteria Anatoxin-a eDNA Phycocyanin Phycoerythrin

Alternative Methods f.r Analysis of.Cyanobacterial Populations in Drinking Water Supplies: f.uorometric and Toxicological Applications Using Phycocyanin

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Journal of.Water Resource and Protection 2018年第8期10卷 740-761页

作者： Nancy J. Leland james f. haney Lim-Tex North Andover MA USA Department of.Zoology University of New Hampshire Durham NH USA

The management of.cyanobacteria and potential exposure to associated biotoxins requires the allocation of.scarce resources across a range of.f.eshwater resources within various jurisdictions. Cost ef.ective and reliable methods f.r sample processing and analysis f.rm the f.undation of.the protocol yielding reliable data f.om which to derive important decisions. In this study the utilization of.new methods to collect, process and analyze samples enhanced our ability to evaluate cyanobacterial populations. Extraction of.phycocyanin using the single f.eeze thaw method provided more accurate and precise measurements (CV 4.7% and 6.4%), of.ering a simple and cost-ef.ective means to overcome the inf.uence of.morphological variability. In-vacuo concentration of.samples prior to ELISA analysis provided a detection limit of.0.001 μg·L?1 MC. f.actionation of.samples (?1) = ?0.279 + (1.368 ? Log PC (μg·L?1) while in an Aphanizomemon spp. dominant system Log MC (ng·L?1) = 0.385 + (0.449 ? Log PC (μg·L?1). These methods and sampling protocol could be used in other aquatic systems across a broader regional landscape to estimate the levels of.microcystins.

关键词： Cyanobacteria Size f.actions f.uorometry Monitoring Phycocyanin Extraction

Trophic Interactions between Anadromous Juvenile Alewif. (<i>Alosa pseudoharengus</i>) and Cyanobacterial Populations in a Shallow Mesotrophic Pond

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Natural Resources 2020年第9期11卷 394-419页

作者： Nancy J. Leland Ryan A. Landon james f. haney Department of.Zoology University of New Hampshire Durham NH USA Lim-Tex North Andover MA USA

Alosa pseudoharengus is an anadromous f.sh that migrates f.om marine to f.eshwaters to spawn. The early larval and juvenile f.rms are known to be planktivorous, where heavy f.eding upon their pref.rred f.od source of.... 详细信息

Alosa pseudoharengus is an anadromous fish that migrates from marine to freshwaters to spawn. The early larval and juvenile forms are known to be planktivorous, where heavy feeding upon their preferred food source of large crustacean zooplankton often results in changes to composition and size structure within this trophic guild which in turn can result in shifts within the trophic spectrum and a classic trophic cascade. In this study of Lower Mill Pond, Brewster MA, we evaluated the feeding strategy of juvenile Alosa to determine whether juvenile alewife switches to feeding largely on cyanobacteria and whether cyanotoxins microcystin (MC) and β-methlyamino-L-alanine (BMAA) bioaccumulate in their muscle tissue. Within 15 - 30 days of their estimated spawning date, overexploitation of crustacean zooplankton resulted in a shift from planktivory to benthic detritivory for the majority of their life history, although this did not reduce their condition based on weight-length relationships (Log Wwt. = -5.503 + (3.101 ×f.nt-f.mily:Verdana;"> Log Length). Mean MC (0.003 μgf.nt-f.mily:Verdana, Helvetica, Arial;white-space:normal;background-color:#f.f.f.;

关键词： Cyanobacteria Juvenile Alewif. Cyanotoxins MC BMAA Bioaccumulation Trophic Spectrum

Evaluation of.Size Structure in f.eshwater Cyanobacterial Populations: Methods to Quantif. Risk Associated with Changes in Biomass and Microcystin Concentrations

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Journal of.Water Resource and Protection 2019年第6期11卷 810-829页

作者： Nancy J. Leland james f. haney Kristin Conte Karen Malkus-Benjamin Bryan Horsely Lim-Tex North Andover MA USA Department of.Zoology University of New Hampshire Durham NH USA Manchester Water Works Manchester NH USA Town of.Barnstable Barnstable MA USA Association to Preserve Cape Cod Dennis MA USA

Cyanobacterial populations in surf.ce waters, including drinking water supplies and recreational waters, represent an ever present challenge f.r resource managers. As communities continuously respond to external and internal processes, dynamic prof.les of.composition, dominance, growth and toxigenicity emerge. In this study measures of.size structure and biomass, quantif.ed using light microscopy and f.uorometry, were used to estimate microcystin concentrations through linear regression analysis. Toxigenic prof.les using cyanobacterial biomass were developed f.r lakes dominated by Microcystis spp. and Dolichospermum spp., inf.uenced by both genus-specif.c pigment concentrations as well as microcystin concentrations. Community composition (Log %MIC) and biomass were used to describe microcystin concentrations in mixed assemblages, where composition was the f.rst input variable. The accessory photopigment phycocyanin was used to describe the linear relationship between the daily growth and net microcystin production rates in the bloom-f.rming Microcystis spp. samples, suggesting that this size-f.actionated sample may provide indications of.potential toxigenicity in the whole lake water sample. f.ture investigations using f.uorometric evaluation of.cyanobacterial populations could provide additional applications and metrics f.r use by resource managers to quantif. risk association with elevated cyanotoxin concentrations.

关键词： Microcystis Dolichospermum Phycocyanin Microcystins Growth Rates

Commentary on“Incidence of.urinary incontinence f.llowing endoscopic laser enucleation of.the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of.5068 patients”

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Asian Journal of.Andrology 2024年第3期26卷 333-334页

作者： james f.Jiang Narmina K Onder Akhil K Das Department of.Urology University of California Irvine Orange CA 92868 USA.

Laser enucleation of.the prostate is a proven and ef.ectivesize-independent method f.r the surgical management of.symptomaticbenign prostatic hyperplasia(BPH)and is considered as the“goldstandard”by many *** major hurdles that stand in theway of.this becoming a universally used procedure f.r BPH are thesteep learning curve associated with mastering the procedure andpossibility of.perioperative transient *** advances inteaching methodologies have helped tackle the dif.iculty in learning itand increased the number of.urologists utilizing the *** f.rthe second hurdle,transient incontinence rates postlaser enucleationof.the prostate have improved with the advent of.newer techniques *** et al.1 assesses the incidence of.stress,urge,andmixed urinary incontinence f.llowing laser enucleation of.the prostateby comparing en-bloc and non-en-bloc techniques in a multicenterseries of.5068 men with BPH.

关键词： urinary incontinence transient

Nickel sulf.te solution f.uoride separation with hydrous zirconium oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert M.Nigri Ummul K.Sultana André L.A.Santos james W.Vaughan Sonia D.f.Rocha Department of.Mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of.Chemical Engineering University of QueenslandSt Lucia 4072Australia

f.uoride is an impurity in nickel sulf.te production,which is required f.r electric vehicle *** zirconium oxide(HZO)was evaluated f.r removing f. uoride f.om nickel sulf.te *** f.uoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen f.uoride and zirconium f.uoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,f.llowed by slow removal up to 68 wt.%af.er 72 h and f.llows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–f.bonds were observed using f.urier-transf.rm inf.ared *** presence of.nickel sulf.te decreased loading capacity compared to a salt-f.ee *** maintained adsorption capacity through f.ve cycles of.loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulf.te f.uoride Adsorption Anion exchange

理解老年人的身体活动:基于时空行为视角的研究

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体育科学 2024年第1期44卷 78-87页

作者：成佳俐仇军 james f.Sallis 于洪军河北师范大学公共体育教学部河北石家庄050024 湖州师范学院体育与大健康研究院浙江湖州313000 美国加州大学圣地亚哥分校家庭医学与公共卫生系加利福尼亚圣地亚哥92093 清华大学体育部北京100084

目的:从时空行为视角对建成环境与老年人户外身体活动的时空行为特征进行研究,为促进我国老年人身体活动水平提升和应对老龄化趋势提供新思路。方法:采用全球定位系统(global position system,GPS)和三维加速度计对126名老年人时空行为... 详细信息

目的:从时空行为视角对建成环境与老年人户外身体活动的时空行为特征进行研究,为促进我国老年人身体活动水平提升和应对老龄化趋势提供新思路。方法:采用全球定位系统(global position system,GPS)和三维加速度计对126名老年人时空行为数据进行同步收集,通过空间算法将环境暴露数据与身体活动数据相关联,总结其出行方式、出行时间、出行频率、出行范围等特征。结果:1)老年人户外身体活动存在“点-线”型、“候鸟”型、“条链”型、“自由”型、“邻里”型、“综合”型6种时空模式;2)老年人主要户外身体活动范围为家附近500 m左右;3)老年人近45%的热量消耗和中高强度身体活动发生在户外空间,主要户外活动兴趣点为休闲娱乐、购物和运动健身;4)老年人户外身体活动特征以出行频率高和短时耗为主,出行次数对身体活动水平有显著影响,出行次数每增加1次,平均每周户外身体活动水平增加20.5 min。结论:我国老年人户外身体活动呈现出多样化的时空行为模式,未来可以将增加出行次数作为促进老年人身体活动水平的切入点。

关键词：时空行为建成环境老年人户外身体活动

What diameter?What height?Inf.uence of.measures of.average tree size on area-based allometric volume relationships

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f.rest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang John A.Kershaw Mark J.Ducey Yuan Sun james B.McCarter Integrated f.rest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of.Natural Resources and the Environment University of New HampshireDurhamNHUSA College of.f.restry Nanjing Forestry UniversityNanjing210037China Scientif.c Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many f.rest management *** f.om 83 f.xed-area plots located in central New Brunswick,Canada,are used to examine how dif.erent measures of.stand-level diameter and height inf.uence volume prediction using a stand-level variant of.Honer's(1967)volume *** density was included in the models(Volume=f.Diameter,Height,Density))choice of.diameter measure was more important than choice of.height *** density was not included(Volume=f.Diameter,Height)),the opposite was *** models with density included,moment-based estimators of.stand diameter and height perf.rmed better than all other *** models without density,largest tree estimators of.stand diameter and height perf.rmed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of.the largest trees needed to calculate a stand density index of.400 and the mean height of.the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of.this study have some important implications f.r height subsampling and LiDAR-derived f.rest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attributes

亚热带森林植物的叶片和根系功能性状部分耦合但具有不同的群落性状分布格局

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Journal of.Plant Ecology 2024年第1期17卷 94-110页

作者： Wenqi Luo Oscar J Valverde-Barrantes Monique Weemstra james f.Cahill Jr Zi Wang Dong He Yongf. Chen Chengjin Chu Youshi Wang State Key Laboratory of.Biocontrol School of Life Sciences/School of EcologySun Yat-sen UniversityGuangzhou 510275China International Center f.r Tropical Botany Department of Biological SciencesFlorida International UniversityMiamiFL 33199USA Department of.Biological Sciences University of AlbertaEdmontonABT6G 2E9Canada School of.Ecology and the Environment Xinjiang UniversityUrumqi 830046China

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变... 详细信息

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变异,是否表现出类似的CTD,其CTD和群落加权平均性状值(CWM)是否沿环境梯度表现出类似的响应。研究结果表明,叶片和根系性状变异的第一轴均呈显出由资源获取向资源保守变异的经济学谱,但叶片变异的第二轴主要由叶片碳含量表征,而根系变异的第二轴主要由反映菌根协作程度的根系粗细表征。类比的叶片和根系化学性状整体正相关,但形态性状的耦合程度较低。在群落水平上,叶片和根系性状第一轴的CWM均随海拔升高而变得更保守,而第二轴的变化则不一致。随土壤磷含量的降低或钾含量的升高,根系变得更细和在养分性状上更保守,而叶片性状无显著变化。当整合多维性状轴时,叶片性状呈发散格局,且随海拔、土壤磷和钾含量的增加呈收敛趋势;而根系性状呈收敛格局,但沿上述环境梯度呈发散趋势。该研究强调,叶片和根系性状与环境互作的差异可能导致不同的性状分布格局;植物可通过多样的地上和地下功能设计应对环境异质性。

关键词：性状维度群落构建叶片性状根系性状植物经济谱群落性状结构亚热带森林

Methionine sources and genotype af.ect embryonic intestinal development,antioxidants,tight junctions,and growth-related gene expression in chickens

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Animal Nutrition 2024年第1期16卷 218-230页

作者： james K.Lugata Sawadi f.Ndunguru Gebrehaweria K.Reda Xénia E.Ozsváth Eszter Angyal Levente Czeglédi Gabriella Gulyás Renáta Knop János Oláh Zoltán Mészár Rita Varga Brigitta Csernus Csaba Szabó Department of.Animal Nutrition and Physiology Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Department of.Animal Husbandry Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary f.culty of.Agriculture and f.od Sciences and Environmental Management Doctoral School of Animal ScienceUniversity of DebrecenDebrecenHungary Institutes f.r Agricultural Research and Educational f.rm University of DebrecenDebrecenHungary Department of.Anatomy Histology and EmbryologyFaculty of MedicineUniversity of DebrecenDebrecenHungary Department of.Evolutionary Zoology and Human Biology Faculty of Science and TechnologyUniversity of DebrecenDebrecenHungary

Methionine(Met)is an essential and f.rst limiting amino acid in the poultry diet that plays a signif.cant role in chicken embryonic development and *** present study examined the ef.ect of.in ovo injection of.DL-Met and L-Met sources and genotypes on chicken embryonic-intestinal development and *** eggs of.the two genotypes,TETRA-SL layer hybrid(TSL)—commercial layer hybrid and Hungarian Partridge colored hen breed(HPC)—a native genotype,were randomly distributed into f.ur treatments f.r each *** treatment groups include the f.llowing:1)control non-injected eggs(NoIn);2)saline-injected(SaIn);3)DL-Met injected(DLM);and 4)L-Met injected(LM).The in ovo injection was carried out on 17.5 d of.embryonic development;af.er hatching,eight chicks per group were sacrif.ced,and the jejunum was extracted f.r *** results showed that both DLM and LM groups had enhanced intestinal development as evidenced by increased villus width,villus height,and villus area(Pf.cantly reduced crypt depth,glutathione(GSH)content,glutathione S-transf.rase 3 alpha(GST3),occludin(OCLN)gene expression and increased villus height to crypt depth ratio in the TSL genotype than the LM group(Pf.ctor 1(IGf.)gene,tricellulin(MD2),occludin(OCLN),superoxide dismutase 1(SOD1),and GST3 genes than the TSL genotype(Pf.ndings showed that in ovo injection of.Met enhanced intestinal development,and f.nction,with genotypes responding dif.erently under normal *** also inf.uenced the expression of.intestinal antioxidants,tight junction,and growth-related genes.

关键词： DL-Methionine L-Methionine In ovo injection Intestinal development Poultry