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Exploring the adjustment to parasite pressure hypothesis: differences in uropygial gland volume and haemosporidian infection in palearctic and neotropical birds

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Current Zoology 2021年第2期67卷 147-156页

作者： Sergio MAGALLAnES Anders Pape MøLLER charlene luján-vega Esteban FOnG Daniel VECCO Wendy FLORES-SAAVEDRA Luz GARCÍA-LOnGORIAA Florentino DE LOPE JoséA.IAnnACOnE Alfonso MARZAL Department of Anatomy Cellular Biology and ZoologyUniversity of ExtremaduraAvda.de Elvas S/NBadajoz ES-06006Spain Ecologie Systématique Evolution UniversitéParis-SudOrsay 91400France Key Laboratory for Biodiversity Science and Ecological Engineering of Ministry of Education College of Life SciencesBeiing Normal UniversityBeiing 100875China Pharmacology and Toxicology Graduate Group University of CaliforniaDavisDavisCA 95616USA EverGreen Institute-San Rafael Distrito de IndianaLoreto 16200Perú Centro Urku de Estudios Amazónicos Tarapoto 22202Perú Universidad nacional Agraria La Molina Lima 15024Perú Molecular Ecology and Evolution Lab Department of BiologyLund UniversityLund 22100Sweden Laboratorio de Ingenieria Ambiental Universidad Cientifica del Sur-Villa el SalvadorLima 15067Perú Laboratorio de Invertebrados Universidad Ricardo PalmaSantiago de Surco 15039Perú

Parasites are globally widespread pathogenic organisms,which impose im portant selective forces upon their ***,in accordance with the A djustm ent to parasite pressure hypothesis,it is expected that defenses among hosts vary relative to the selective pressure imposed by *** to the latitudinal gradient in diversity,species richness and abundance of parasites peak near the *** uropygial gland is an im portant defensive exocrine gland against pathogens in *** of the uropygial gland has been proposed to vary among species of birds because of divergent selection by pathogens on their ***,we should expect that bird species from the tropics should have relatively larger uropygial glands for their body size than species from higher ***,this hypothesis has not yet been ***,we analyze the size of the uropygial gland of 1719 individual birds belonging to 36 bird species from 3 neotropical(Peru)and 3 temperate areas(Spain).Relative uropygial gland volum e was 12.52%larger in bird species from the tropics than from temperate *** finding is consistent w ith the relative size of this defensive organ being driven by selective pressures imposed by *** also explored the potential role of this gland as a means of avoiding haemosporidian infection,showing that species with large uropygial glands for their body size tend to have lower mean prevalence of haemosporidian infection,regardless o f their geographical *** result provides additional support for the assum ption that secretions from the uropygial gland reduce the likelihood of becoming infected with haemosporidians.

关键词： adjustment to parasite pressure hypothesis malaria neotropical region preen oil temperate region

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Practical semen analysis： from A to Z

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Asian Journal of Andrology 2010年第1期12卷 14-20页

作者： charlene Brazil Center for Health and the Environment University of California Davis CA 95616 USA

Accurate semen analysis is critical for decisions about patient care, as well as for studies addressing overall changes in semen quality, contraceptive efficacy and effects of toxicant exposure. The standardization of semen analysis is very difficult for many reasons, including the use of subjective techniques with no standards for comparison, poor technician training, problems with proficiency testing and a reluctance to change techniques. The World Health Organization （WHO） Semen handbook （2010） offers a vastly improved set of standardized procedures, all at a level of detail that will preclude most misinterpretations. However, there is a limit to what can be learned from words and pictures alone. A WHO- produced DVD that offers complete demonstrations of each technique along with quality assurance standards for motility, morphology and concentration assessments would enhance the effectiveness of the manual. However, neither the manual nor a DVD will help unless there is general acknowledgement of the critical need to standardize techniques and rigorously pursue quality control to ensure that laboratories actually perform techniques ＇according to WHO＇ instead of merely reporting that they have done so. Unless improvements are made, patient results will continue to be compromised and comparison between studies and laboratories will have limited merit.

关键词： andrology laboratory quality assurance semen analysis sperm concentration sperm morphology sperm motility

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Presenilins as endoplasmic reticulum calcium leak channels and Alzheimer's disease pathogenesis

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Science China(Life Sciences) 2011年第8期54卷 744-751页

作者： charlene SUPnET Ilya BEZPROZVAnnY Department of Physiology University of Texas Southwestern Medical Center at Dallas

Alzheimer disease(AD) is the most common neurodegenerative disorder worldwide and is at present,*** accumulation of toxic amyloid-beta(Aβ) peptide aggregates in AD brain is thought to trigger the extensive synaptic loss and neurodegeneration linked to cognitive decline,an idea that underlies the'amyloid hypothesis'of AD etiology in both the familal(FAD) and sporadic forms of the *** mutations causing FAD also result in the dysregulation of neuronal calcium(Ca2+) handling and may contribute to AD pathogenesis,an idea termed the'calcium hypothesis'of *** in presenilin proteins account for majority of FAD *** function as catalytic subunit ofγ-secretase involved in generation of Aβ peptide Recently,we discovered that presenilns function as low-conductance,passive ER Ca2+ leak channels,independent of γ-secretase *** further discovered that many FAD mutations in presenilins result in loss of ER Ca2+ leak function activity and Ca2+ overload in the *** results provided potential explanation for abnormal Ca2+ signaling observed in FAD cells with mutations in *** latest work on studies of ER Ca2+ leak channel function of presenilins and implications of these findings for understanding AD pathogenesis are discussed in this article.

关键词： calcium signaling neurodegeneration presenilins Alzheimer's disease gamma-secretase amyloid

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Hard to fly the nest： A study of body condition and plumage quality in house sparrow fledglings

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Current Zoology 2014年第4期60卷 449-459页

作者： charlene LELOUTRE Alice GOUZERH Frederic AnGELIER Centre d'Etudes Biologiques de Chiz6 CNRS F-79360 Villiers en Bois France

Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands： After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling＇s state （body condition, fat and muscle scores and plumage quality）. If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. Overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors （mortality, dispersal, habitat use and behaviours） and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 （4）： 449-459, 2014].

关键词： Body condition Fault bar Fat score Muscle score Passer domesticus

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Therapeutics involved in managing initial and recurrent Clostridium difficile infection:An updated literature review

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2024年第5期15卷 1-14页

作者： Vignesh K nagesh Hadrian Hoang-Vu Tran Daniel Elias Izage Kianifar Aguilar Tanni Sethi AiswaryaMenon charlene Mansour Florchi Furman Kylie Tsotsos Talia Subar Auda Auda Aman Sidiqui JevonLamar nikita Wadhwani Shraboni Dey Abraham Lo Adam Atoot Simcha Weissman Humberto Sifuentes Ayrton I Bangolo Department of Internal Medicine Hackensack Palisades Medical CenterNorth BergenNJ 07047United States Department of Gastroenterology Augusta UniversityAugustaGA 30912United States

Clostridium difficile infection(CDI)has been increasing due to the effect of recurrent *** use of antibiotics has been shown to alter the gut microbiome and lead to *** treatment is limited to three major antibiotics;however,the incidence of recurrent CDIs has been increasing and drug resistance is a major *** aspect is a growing concern in modern medicine especially in the elderly population,critical care patients,and immunocompromised individuals who are at high risk of developing *** difficile can lead to various complications including septic shock and fulminant colitis that could prove to be lethal in these *** modalities of treatment have been developed including bezlotoxumab,a monoclonal antibody and fecal microbiota *** have been studies showing asymptomatic carriers and drug resistance posing a major threat to the healthcare *** treatment options are being studied to treat and prevent *** review will provide an insight into the current treatment modalities,prevention and newer modalities of treatment and challenges faced in the treatment of CDIs.

关键词： Clostridium difficile Antibiotics Vancomycin Fidaxomicin Prevention Bezlotoxumab Fecal microbiota transplant

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Poultry gut health-microbiome functions,environmental impacts,microbiome engineering and advancements in characterization technologies

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Journal of Animal Science and Biotechnology 2022年第2期13卷 338-352页

作者： Christiana Eleojo Aruwa charlene Pillay Martin M.nyaga Saheed Sabiu Department of Biotechnology and Food Science Faculty of Applied SciencesDurban University of TechnologyP.O.Box 1334Durban 4000South Africa next Generation Sequencing Unit Division of VirologyFaculty of Heath SciencesUniversity of the Free StateBloemfonteinSouth Africa

The gastrointestinal tract(GIT)health impacts animal *** poultry microbiome has functions which range from protection against pathogens and nutrients production,to host immune system *** in the microbiome have also been linked to prevailing environmental *** poultry birds possess a natural resistance to ***,the exploration of environmental impacts and other relevant factors on poultry growth and health have been *** good performance and growth rate are central to animal production,the host-microbiome relationship remains *** to the emergence of metagenomic techniques,conventional methods for poultry microbiome studies were used and were low-throughput and associated with insufficient genomic data and high cost of ***,the advent of high-throughput sequencing platforms have circumvented some of these shortfalls and paved the way for increased studies on the poultry gut microbiome diversity and ***,we give an up-to-date review on the impact of varied environments on microbiome profile,as well as microbiome engineering and microbiome technology *** is hoped that this paper will provide invaluable information that could guide and inspire further studies on the lingering pertinent questions about the poultry microbiome.

关键词： Disease Environmental impacts Gut microbiome Microbiome engineering Poultry health

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Incorporation of Biochar Carbon into Stable Soil Aggregates:The Role of Clay Mineralogy and Other Soil Characteristics

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Pedosphere 2017年第4期27卷 694-704页

作者： charlene n. KELLY Joseph BEnJAMIn Francisco C. CALDEROn Maysoon M. MIKHA David W. RUTHERFORD Colleen E. ROSTAD West Virginia University Division of Forestry and Natural Resources337 Percival HallMorgantownWV 26506USA USDA-ARS Central Great Plains Research Station40335 County RoadGGAkronCO 80720USA U.S.Geological Survey MS 408PO Box 25046Building 95Denver Federal CenterDenverCO 80225USA

Aggregation and structure play key roles in water-holding capacity and stability of *** this study,the incorporation of carbon(C) from switchgrass biochar into stable aggregate size fractions was assessed in an Aridisol(from Colorado,USA) dominated by 2:1 clays and an Alfisol(from Virginia,USA) containing weathered mixed 1:1 and 2:1 mineralogy,to evaluate the effect of biochar addition on soil *** biochar was applied at 4 levels,0,25,50,and 100 g kg^(-1),to the soils grown with wheat in a growth chamber *** changes in soil strength and water-holding capacity using water release curves were *** the Colorado soil,the proportion of soil occurring in large aggregates decreased,with concomitant increases in small size *** changes in aggregate size fractions occurred in the Virginia *** the Colorado soil,C content increased from 3.3 to 16.8 g kg^(-1),whereas in then C content increased from 5.7 to 22.6 g kg^(-1) with 100 g kg^(-1)biochar *** the Virginia soil,C content within aggregate size fractions increased for each size fraction,except the>2 000 μm *** greatest increase(from 6.2 to 22.0 g kg^(-1)) occurred in the 53–250 μm *** results indicated that C was incorporated into larger aggregates in the Virginia soil,but remained largely unassociated to soil particles in the Colorado *** addition had no significant effect on water-holding capacity or strength *** biochar to more weathered soils with high native soil organic content may result in greater stabilization of incorporated C and result in less loss because of erosion and transport,compared with the soils dominated by 2:1 clays and low native soil organic content.

关键词： aggregate size fractions, aggregate stability, mineralogy, soil strength, water-holding capacity, weathered soil

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Research on Factors Determining Capital Structure of non-Financial Firms in Sub-saharan Region of Africa

Research on Factors Determining Capital Structure of Non-Fin...

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作者： charlene Rufaro Kadzunge 浙江工商大学

学位级别：硕士

非金融公司或企业是一国经济发展非常重要的环节,对于促进一国金融发展具有重要意义。很长一段时间以来,资本结构是公司金融领域里的热门研究主题。资本结构是公司长期债务和股权的最合适组合,也是影响重要公司政策方向的基础,因为它涉... 详细信息

非金融公司或企业是一国经济发展非常重要的环节,对于促进一国金融发展具有重要意义。很长一段时间以来,资本结构是公司金融领域里的热门研究主题。资本结构是公司长期债务和股权的最合适组合,也是影响重要公司政策方向的基础,因为它涉及公司的经营活动以及债务和股权比率。本文以非洲撒哈拉以南地区非金融公司为研究样本,以探究资本结构的影响因素。本文选取了2000年至2020年间54家非金融企业的面板数据。基于Hausman检验结果,运用固定效应模型实证分析企业规模、盈利能力等因素对企业资本结构的影响。在单位根检验之后,本文得出结论在5%的显著性水平下,所有变量在第一阶差分后都是平稳的,协整结果表明企业规模、盈利能力等因素与企业资本结构存在长期稳定关系。固定效应模型估计表明,盈利能力和流动性之间存在负相关关系。研究结果支持了对啄序理论的理解。本文还发现企业规模与负债率之间存在显著的相关关系;不同的是,本文发现了利率和资本结构之间并无显著相关性。实证研究结果表明,资本结构是企业规模、利润波动率、盈利能力、流动性和现金波动率等多个变量的函数。正因为这些因素决定了企业的生死存亡,企业积极主动地确定资本结构里的组成部分是至关重要的。

关键词：资本结构现金流波动率收益波动率利率盈利能力流动性规模非洲

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Switchgrass Biochar Effects on Plant Biomass and Microbial Dynamics in Two Soils from Different Regions

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Pedosphere 2015年第3期25卷 329-342页

作者： charlene n.KELLY Francisco C.CALDERón Verónica ACOSTA-MARTínEZ Maysoon M.MIKHA Joseph BEnJAMIn David W.RUTHERFORD Colleen E.ROSTAD Western Carolina University Department of Geosciences and Natural Resources331 Stillwell HallCullowheeNC 28723 (USA) U.S.Geological Survey Denver CO 80225 (USA) USDA-ARS Akron CO 80720 (USA) USDA-ARS Lubbock TX 79403 (USA)

Biochar amendments to soils may alter soil function and fertility in various ways, including through induced changes in the microbial community. We assessed microbial activity and community composition of two distinct clayey soil types, an Aridisol from Colorado （CO） in the U.S. Central Great Plains, and an Alfisol from Virginia （VA） in the southeastern USA following the application of switchgrass （Panicum virgatum） biochar. The switchgrass biochar was applied at four levels, 0%,0, 2.5%, 5%, and 10%, approximately equivalent to biochar additions of 0, 25, 50, and 100 t ha^-1, respectively, to the soils grown with wheat （Triticum aestivum） in an eight-week growth chamber experiment. We measured wheat shoot biomass and nitrogen （n） content and soil nutrient availability and n mineralization rates, and characterized the microbial fatty acid methyl ester （FAME） profiles of the soils. net n mineralization rates decreased in both soils in proportion to an increase in biochar levels, but the effect was more marked in the VA soil, where net n mineralization decreased from -2.1 to -38.4 mg kg^-1. The 10% biochar addition increased soil pH, electrical conductivity, Mehlich- and bicarbonate-extractable phosphorus （P）, and extractable potassium （K） in both soil types. The wheat shoot biomass decreased from 17.7 to 9.1 g with incremental additions of biochar in the CO soil, but no difference was noted in plants grown in the VA soil. The FAME recovery assay indicated that the switchgrass biochar addition could introduce artifacts in analysis, so the results needed to be interpreted with caution. non-corrected total FAME concentrations indicated a decline by 457o and 34% with 10% biochar addition in the CO and VA soils, respectively, though these differences became nonsignificant when the extraction efficiency correction factor was applied. A significant decline in the fungi：bacteria ratio was still evident upon correction in the CO soil with biochar. Switchgrass biochar had the p

关键词： correction factor extraction efficiency fatty acid methyl ester profile nitrogen mineralization soil microbial community soil nutrient availability wheat

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Bacteriophage M13 as a Scaffold for Preparing Conductive Polymeric Composite Fibers

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nano Research 2008年第3期1卷 235-241页

作者： Zhongwei niu Michael ABruckman Brandon Harp charlene MMello Qian Wang Department of Chemistry and Biochemistry and nanocenter University of South CarolinaColumbiaSC 29208USA Bioscience and Technology Team US Army Natick Soldier ResearchDevelopment&Engineering CenterNatickMA 01760-5020USA

Using biological templates to build one-dimensional functional materials holds great promise in developing nanosized electrical devices,sensors,catalysts,and energy storage *** this communication,we report a versatile assembly process for the preparation of water-soluble conductive polyaniline(PAni)/M13 composite nanowires by employing the bacteriophage M13 as a *** surface lysine residues of M13 can be derivatized with carboxylic groups to improve its binding ability to the aniline;the resulting modifi ed M13 is denoted as *** negatively-charged poly(sulfonated styrene)was used both as a dopant acid and a stabilizing agent to enhance the stability of the composite fi bers in aqueous solution.A transparent solution of the conductive PAni/m-M13 composite fi bers can be readily obtained without any further purifi cation *** fi bers can be easily fabricated into thin conductive fi lms due to their high aspect ratio and good solubility in aqueous *** synthesis discloses a unique and versatile way of using bionanorods to produce composite fi brillar materials with narrow dispersity,high aspect ratio,and high processibility,which may have many potential applications in electronics,optics,sensing,and biomedical engineering.

关键词： Bacteriophage M13 nanofi ber conductive polymer self-assembly bioconjugation

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