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The complexities of female mate choice and male polymorphisms： Elucidating the role of genetics, age, and mate-choice copying

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Current Zoology 2015年第6期61卷 1015-1035页

作者： Kasey D. FOWLER-FINN Laura SULLIVAN-BECKERS amy m. RUNCK Eileen A. HEBETS School of Biological Sciences University of Nebraska Lincoln NE 68508 USA

Genetic, life history, and environmental factors dictate patterns of variation in sexual traits within and across populations, and thus the action and outcome of sexual selection. This study explores patterns of inheritance, diet, age, and mate-choice copying on the expression of male sexual signals and associated female mate choice in a phenotypically diverse group of wolf spiders. Focal spiders exhibit one of two male phenotypes: 'ornamented' males possess large black brushes on their forelegs, and 'non-ornamented' males possess no brushes. Using a quantitative genetics breeding design in a mixed population of ornamented/non-ornamented males, we found a strong genetic basis to male phenotype and female choice. We also found that some ornamented males produced some sons with large brushes and others with barely visible brushes. Results of diet manipulations and behavioral mating trials showed no influence of diet on male phenotype or female mate choice. Age post maturation, however, influenced mate choice, with younger females being more likely to mate with ornamented males. A mate-choice copying experiment found that, following observations of another female's mate choice/copulation, virgin mature females tended to match the mate choice (ornamented vs. non-ornamented males) of the females they observed. Finally, analyses of genetic variation across phenotypically pure (only one male phenotype present) vs. mixed (both phenotypes present) populations revealed genetic distinction between phenotypes in phenotypically-pure populations, but no distinctionin phenotypically-mixed populations. The difference in patterns of genetic differentiation and mating across geographic locations suggests a complex network of factors contributing to the outcome of sexual selection.

关键词：数量遗传学基因多态性男性女性择偶年龄复杂性表型选择

Exacerbated VEGF up-regulation accompanies diabetes-aggravated hemorrhage in mice after experimental cerebral ischemia and delayed reperfusion

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Neural Regeneration Research 2022年第7期17卷 1566-1575页

作者： Angela Ka Wai Lai Tsz Chung Ng Victor Ka Lok Hung Ka Cheung Tam Chi Wai Cheung Sookja Kim Chung amy Cheuk Yin Lo Department of Ophthalmology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administration RegionChina Department of Anesthesiology Laboratory and Clinical Research Institute for PainThe University of Hong KongHong Kong Special Administration RegionChina macao University of Science and Technology TaipaMacao Special Administration RegionChinaSchool of Biomedical SciencesThe State Key Laboratory of Pharmaceutical BiotechnologyThe University of Hong KongHong Kong Special Administration RegionChina

Reperfusion therapy is the preferred treatment for ischemic stroke,but is hindered by its short treatment window,especially in patients with diabetes whose reperfusion after prolonged ischemia is often accompanied by exacerbated *** mechanisms underlying exacerbated hemorrhage are not fully *** study aimed to identify this mechanism by inducing prolonged 2-hour transient intraluminal middle cerebral artery occlusion in diabetic Ins2Akita/+mice to mimic patients with diabetes undergoing delayed mechanical *** results showed that at as early as 2 hours after reperfusion,Ins2Akita/+mice exhibited rapid development of neurological deficits,increased infarct and hemorrhagic transformation,together with exacerbated down-regulation of tight-junction protein ZO-1 and upregulation of blood-brain barrier-disrupting matrix metallopeptidase 2 and matrix metallopeptidase 9 when compared with normoglycemic Ins2+/+*** indicated that diabetes led to the rapid compromise of vessel integrity immediately after reperfusion,and consequently earlier death and further aggravation of hemorrhagic transformation 22 hours after *** observation was associated with earlier and stronger up-regulation of pro-angiogenic vascular endothelial growth factor(VEGF)and its downstream phospho-Erk1/2 at 2 hours after reperfusion,which was suggestive of premature angiogenesis induced by early VEGF up-regulation,resulting in rapid vessel disintegration in diabetic *** reticulum stress-related pro-apoptotic C/EBP homologous protein was overexpressed in challenged Ins2Akita/+mice,which suggests that the exacerbated VEGF up-regulation may be caused by overwhelming endoplasmic reticulum stress under diabetic *** conclusion,the results mimicked complications in patients with diabetes undergoing delayed mechanical thrombectomy,and diabetes-induced accelerated VEGF up-regulation is likely to underlie exacerbated hemorrhagic transformat

关键词： blood-brain barrier brain injury diabetes mellitus hemorrhagic transformation infarct ischemia/reperfusion injury middle cerebral artery occlusion mouse model stroke vascular endothelial growth factor

Land tenure and landscape change:a comparison of public-private lands in the southern High Plains

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Ecological Processes 2016年第1期5卷 139-152页

作者： Todd D.Fagin Jacqueline m.Vadjunec Nicole m.Colston Kathyrn Wenger amy Graham Oklahoma Biological Survey University of Oklahoma111 E.Chesapeake StNorman 73019OKUSA Department of Geography Oklahoma State University337 Murray HallStillwater 74078OKUSA

Introduction:Long-term drought in the southern Great Plains increases the vulnerability of coupled human-environment systems at a variety of *** better understandings of the dynamics at regional scales will become increasingly important as long-established land-use regimes break down in the face of climate change,resource depletion,and evolving *** demonstrate differential vulnerability during drought periods,this study hypothesized that observed increases in woody vegetation in grasslands would vary across land-tenure *** argue that differences in State Trust Land governance,in part,lead to differential land management practices that contribute to landscape ***:The study area encompasses adjacent counties,Cimarron County in Oklahoma and Union County in New mexico,with similar climate variability and agricultural *** analyzed National Land Cover Database(NLCD)land-cover maps from 1992 and 2011 to assess changes in landscape composition and structure between 1992 and ***:During both years under consideration,each county in the study region,across various land-tenure regimes,was dominated by herbaceous ***,there were changes in both composition and structure across the whole study area,in particular losses of herbaceous vegetation and increases in woody *** greatest gains in woody vegetation occurred in State Trust Lands of Cimarron ***,the data suggest a fragmentation of herbaceous vegetation and a coalescing of shrubland ***:Research about the influence of land tenure on land management decisions,specifically the role of State Trust Land leases in overgrazing,informs the broader context of drought management in the southern Great *** include continued research to highlight the specific mechanisms of land-tenure governance that drive landscape change.

关键词： Drought Land tenure Agriculture Landscape composition Landscape structure Southern Great Plains Grasslands Socio-ecological vulnerability National Land Cover Database(NLCD)

Twenty years of drought-mediated change in snag populations in mixed-conifer and ponderosa pine forests in Northern Arizona

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Forest Ecosystems 2021年第2期8卷 265-277页

作者： Joseph L.Ganey Jose m.Iniguez Scott C.Vojta amy R.Iniguez US Forest Service Rocky Mountain Research Station2500 S.Pine KnollAZ 86001 FlagstaffUSA

Background:Snags(standing dead trees)are important biological legacies in forest systems,providing numerous resources as well as a record of recent tree *** 1997 to 2017,we monitored snag populations in drought-influenced mixed-conifer and ponderosa pine(Pinus ponderosa)forests in northern ***:Snag density increased significantly in both forest *** increase was driven largely by a pulse in snag recruitment that occurred between 2002 and 2007,fol owing an extreme drought year in 2002,with snag recruitment returning to pre-pulse levels in subsequent time *** later years during the study also were warmer and/or drier than average,but these years were not as extreme as 2002 and did not trigger the same level of snag *** recruitment was not equal across tree species and size classes,resulting in significant changes in species composition and size-class distributions of snag populations in both forest *** trees were far more abundant than snags in these forests,the effect of this mortality pulse on tree populations was far smal er than its effect on snag *** loss rates increased over time during the study,even though many snags were newly *** may reflect the increasing prevalence of white fir snags and/or snags in the smal er size classes,which general y decay faster than snags of other species or larger ***,although total numbers of snags increased,many of the newly recruited snags may not persist long enough to be valuable as nesting substrates for native ***:Increases in snag abundance appeared to be due to a short-term tree mortality"event"rather than a longerterm pattern of elevated tree *** mortality event fol owed a dry and extremely warm year(2002)embedded within a longer-term *** models suggest that years like 2002 may occur with increasing frequency in the southwestern *** years may result in additional mortality pulses,wh

关键词： Climate change Drought monitoring Snag abundance Snag creation Snag dynamics Species composition Tree mortality

Adiponectin signalling in bone homeostasis,with age and in disease

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Bone Research 2021年第1期9卷 15-25页

作者： Jonathan W.Lewis James R.Edwards amy J.Naylor Helen m.mcGettrick Rheumatology Research Group Institute of Inflammation and AgeingUniversity of BirminghamBirmingham B152TTUK Ageing&Regeneration Research Group Botnar Research CentreUniversity of OxfordOxford OX37LDUK

Adiponectin is the most abundant circulating adipokine and is primarily involved in glucose metabolism and insulin *** the bone,osteoblasts and osteoclasts express the adiponectin receptors,however,there are conflicting reports on the effects of adiponectin on bone formation and *** studies have shown a pro-osteogenic role for adiponectin in in vivo murine models and in vitro:with increased osteoblast differentiation and activity,alongside lower levels of ***,human studies often demonstrate an inverse relationship between adiponectin concentration and bone ***,the presence of multiple isoforms of adiponectin and multiple receptor subtypes has the potential to lead to more complex signalling and functional *** such,we still do not fully understand the importance of the adiponectin signalling pathway in regulating bone homeostasis and repair in health,with age and in *** this review,we explore our current understanding of adiponectin bioactivity in the bone;the significance of its different isoforms;and how adiponectin biology is altered in ***,furthering our understanding of adiponectin regulation of bone biology is key to developing pharmacological and non-pharmacological(lifestyle)interventions that target adiponectin signalling to boost bone growth and repair in healthy ageing,following injury or in disease.

关键词： homeostasis metabolism consequences

multigene phylogeny and taxonomy of the genus melanconiella(Diaporthales)

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Fungal Diversity 2012年第6期57卷 1-44页

作者： Hermann Voglmayr amy Y.Rossman Lisa A.Castlebury Walter m.Jaklitsch Department of Systematic and Evolutionary Botany Faculty Centre of BiodiversityUniversity of ViennaRennweg 141030WienAustria Systematic mycology&microbiology Laboratory USDAAgricultural Research ServiceB010A10300 Baltimore AveBeltsvilleMD 20705USA

molecular phylogenetic analyses of LSU rDNA demonstrate monophyly of the genus melanconiella,and its status as a genus distinct from melanconis is *** of macro-and microscopic morphology,pure cultures and phylogenetic analyses of partial SSU-ITS-LSU rDNA,tef1 and rpb2 sequences revealed 13 distinct species of melanconiella,six of which are described as new(***,***,***,***,***,***).melanconiella hyperopta *** is described as a new *** carpinicola,***,***,*** and *** are formally combined into *** name melanconiella chrysostroma is excluded from melanconiella,as it is an obligate synonym of Wuestneia *** type of melanconiella is confirmed as *** species are lecto-and/or epitypified.A key to all treated species ofmelanconiella is provided,and the circumscriptions of the genera melanconis and melanconiella are *** melanconiella species revealed by molecular phylogenetic analyses can be well characterised by a suite of morphological traits including ascospore shape,length and width,colour,absence/presence and shape of appendages and the ***-teleomorph connections were confirmed by pure culture and DNA data,revealing the presence of a single melanconium-or discosporina-like anamorph for each *** growth was found to be characteristic of the respective *** is shown to be confined to the host family Betulaceae,and all species are found to be highly host-specific,mostly confined to a single host *** biodiversity ofmelanconiella was determined to be centred on the genus Carpinus with nine species,five of which have been confirmed on *** appears to be the geographic centre of melanconiella biodiversity.

关键词： High diversity Host specificity melanconidaceae molecular phylogeny New species Pathogen Systematics

Can non-typeable Haemophilus influenzae carriage surveillance data infer antimicrobial resistance associated with otitis media?

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Pediatric Investigation 2023年第1期7卷 13-22页

作者： Sophia Bowman-Derrick Tegan m.Harris Jemima Beissbarth mariana Kleinecke Katrina Lawrence Teresa m.Wozniak amy Bleakley Angela Rumaseb michael J.Binks Robyn L.marsh Peter S.morris Amanda J.Leach Heidi Smith-Vaughan menzies School of Health Research Charles Darwin UniversityDarwinAustralia Australian e-Health Research Centre CSIRO BrisbaneAustralia Royal Darwin Hospital DarwinAustralia

Importance:In remote communities of the Northern Territory,Australia,children experience high rates of otitis media(Om),commonly caused by non-typeable Haemophilus influenzae(NTHi).Few data exist on antibiotic susceptibility of NTHi from ***:To determine whether population-level nasopharyngeal NTHi antibiotic susceptibility data could inform antibiotic treatment for ***:NTHi isolates(n=92)collected from ear discharge between 2003 and 2013 were selected to time-and age-match NTHi isolates from the nasopharyngeal carriage(n=95).Antimicrobial susceptibility were *** trees and a genome-wide association study(GWAS)were performed to determine the similarity of nasopharyngeal and ear isolates at a population ***:Among 174 NTHi isolates available for antimicrobial susceptibility testing,10.3%(18/174)were resistant to ampicillin and 9.2%(16/174)were resistant to *** numbers of isolates(≤3)were resistant to tetracycline,chloramphenicol,or amoxicillin-clavulanic *** was no statistical difference in the proportion of ampicillin-resistant(P=0.11)or trimethoprim-sulfamethoxazole-resistant isolates(P=0.70)between ear discharge and nasopharynx-derived NTHi *** multi-drug resistant NTHi isolates were *** trees showed no clustering of 187 Haemophilus influenzae isolates based on anatomical niche(nasopharynx or ear discharge),and no genetic variations that distinguished NTHi derived from ear discharge and nasopharyngeal carriage were evident in the ***:In this population-level study,nasopharyngeal and ear discharge isolates did not represent distinct microbial *** results support tracking of population-level nasopharyngeal NTHi antibiotic resistance patterns to inform clinical management of Om in this population.

关键词： Haemophilus influenzae Otitis media Antimicrobial resistance

Probing the Impact of Solvent on the Strength of Lewis Acids via Fluorescent Lewis Adducts

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Precision Chemistry 2023年第1期1卷 49-56页

作者： amy E.Laturski Joshua R.Gaffen Paul Demay-Drouhard Christopher B.Caputo Thomas Baumgartner Department of Chemistry York UniversityTorontoON M3J 1P3Canada

Various methods have been developed to measure the strength of a Lewis acid.A major challenge for these measurements lies in the complexity that arises from variable solvent interactions and perturbations of Lewis acids as their reaction environment ***,we investigate the impact of solvent effects on Lewis acids for the first time as measured by the fluorescent Lewis adduct(FLA)*** binding of a Lewis acid in various solvents reveals a measurable dichotomy between both polarity and donor ability of the *** not strictly separable,we observe that the influence of solvent polarity on Lewis acid unit(LAU)values is distinctly opposite to the influence of donor *** dichotomy was confirmed by titration data,illustrating that solvation effects can be appropriately and precisely gauged by the FLA method.

关键词： Fluorescence Fluorescent Lewis adducts Lewis acids Effective Lewis acidity Solvent polarity Solvent donor strength

Exercise-dependent regulation of glial cell line-derived neurotrophic factor （GDNF） expression in skeletal muscle and its importance for the neuromuscular system

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Frontiers in Biology 2013年第1期8卷 101-108页

作者： John-mary VIANNEY monica J. mCCULLOUGH amy m. GYORKOS, John m. SPITSBERGEN Department of Biological Scienees Western Michigan University Kalamazoo MI 49098-5410 USA

The focus of this review is to highlight the importance of glial cell line-derived neurotrophic factor （GDNF） for the motor nervous system. GDNF is the most potent survival factor for motor neurons, where it enhances maintenance and survival of both developing and mature motor neurons in vivo and in vitro. GDNF aids in neuromuscular junction formation, maintenance, and plasticity, where skeletal muscle-derived GDNF may be responsible for this phenomenon. Increased levels of physical activity can increase GDNF protein levels in skeletal muscle, where alterations in acetylcholine and acetylcholine receptor activation may be involved in regulation of these changes observed. With inactivity and disuse, GDNF expression shows different patterns of regulation in the central and peripheral nervous systems. Due to its potent effects for motor neurons, GDNF is being extensively studied in neuromuscular diseases.

关键词： glial cell line-derived neurotrophic factor neuromuscular junction motor neurons skeletal muscle