检索结果-南通市图书馆

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

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Adiponectin signalling in bone homeostasis,with age and in disease

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

multigene phylogeny and taxonomy of the genus melanconiella(Diaporthales)

引用

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

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Focus on nursing pharmacology 5th ed. 5th ed.

引用

2011年

作者： amy m. Karch.

Includes bibliographical references and index.

ISBN: (纸本)9780781789820

Includes bibliographical references and index.

关键词： Pharmacology. Nursing. Pharmaceutical Preparations Drug Therapy Pharmacology

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration

引用

Journal of Forestry Research 2022年第3期33卷 741-753页

作者： Tzeidle N.Wasserman amy E.m.Waltz John Paul Roccaforte Judith D.Springer Joseph E.Crouse Ecological Restoration Institute Northern Arizona UniversityP.O.Box 15017FlagstaffAZ86011-5017USA

Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United *** focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review *** showed that the effects of thinning and burning treatments on regeneration depended on time since *** thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and *** were mixed results in the short-term(m studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments *** studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals.

关键词： Regeneration Ponderosa pine Frequent-fire Treatments Thinning Burning

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Potential underlying genetic associations between keratoconus and diabetes mellitus

引用

Advances in Ophthalmology Practice and Research 2021年第1期1卷 15-31页

作者： Kristin m.Ates amy J.Estes Yutao Liu Department of Cellular Biology and Anatomy Medical College of GeorgiaAugusta UniversityAugustaGAUSA Department of Ophthalmology Medical College of GeorgiaAugusta UniversityAugustaGAUSA James and Jean Culver Vision Discovery Institute Medical College of GeorgiaAugusta UniversityAugustaGAUSA Center for Biotechnology and Genomic medicine Medical College of GeorgiaAugusta UniversityAugustaGAUSA

Background:Keratoconus(KC)is the most common ectatic corneal disease,characterized by significantly localized thinning of the corneal ***,environmental,hormonal,and metabolic factors contribute to the pathogenesis of ***,multiple comorbidities,such as diabetes mellitus,may affect the risk of *** Text:Patients with diabetes mellitus(Dm)have been reported to have lower risk of developing KC by way of increased endogenous collagen crosslinking in response to chronic ***,this remains a debated topic as other studies have suggested either a positive association or no association between Dm and *** gain further insight into the underlying genetic components of these two diseases,we reviewed candidate genes associated with KC and central corneal thickness in the *** then explored how these genes may be regulated similarly or differentially under hyperglycemic conditions and the role they play in the systemic complications associated with ***:Our comprehensive review of potential genetic factors underlying KC and Dm provides a direction for future studies to further determine the genetic etiology of KC and how it is influenced by systemic diseases such as diabetes.

关键词： Keratoconus Genetics Diabetes Collagen crosslinking Oxidative stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impacts of bovine spongiform encephalopathy and avian influenza on U.S. meat demand

引用

Journal of Integrative Agriculture 2015年第6期14卷 1130-1141页

作者： Jianhong E mu Bruce A mcCarl amy Hagerman David Bessler Department of Applied Economics Oregon State University Department of Agricultural Economics Texas A&M University Center for Epidemiology and Animal Health Veterinary Services Animal and Plant Health Inspection Service United States Department of Agriculture

This paper examines the U.S. meat demand impacts of the announced outbreaks of bovine spongiform encephalopathy（BSE） and avian influenza（AI）. Findings indicate that beef and chicken demand was negatively affected by BSE and AI disease outbreaks. Specifically, in the short run, U.S. consumers shift demand due to both outbreaks but more so due to domestic disease outbreaks than for outbreaks occurring overseas-the impact of U.S. AI outbreaks is about 0.5% for beef and the impact of U.S. BSE cases is around –0.42% for beef and 0.4% for pork, respectively. Regarding the BSE shock on meat demand, there is a high rate of beef demand adjusted from disturbance to the long-run equilibrium and a lower adjustment rate for chicken demand because of the repeated outbreaks of AI worldwide. In the long run, information related to severe, persistently recurring overseas animal disease outbreaks changes U.S. consumers＇ meat consumption patterns. Although effects of animal diseases on U.S. meat demand were statistically significant, the magnitudes were small-the impact of WHO reported human death numbers for AI is 0.005% for beef, –0.002% for pork, and –0.006% for chicken and the impact of U.S. BSE cases is 1.1% for pork and –0.7% for chicken.

关键词： spongiform avian chicken bovine encephalopathy overseas disturbance adjustment pathogenic deaths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Digital Humanities Within a Global Context： Creating Borderlands of Localized Expression

引用

Fudan Journal of the Humanities and Social Sciences 2018年第3期11卷 357-369页

作者： amy E. Earhart Department of English Texas A&M University 4227 TAMU College StationTX 77843-4227 USA

As scholars have begun the digitization of the word＇s cultural materials, the understanding of what is to be digitized and how that digitization occurs remains narrowly imagined, with a distinct bias toward North American and European notions of culture, value and ownership. Humanists are well aware that cultural knowledge, aesthetic value and copyright/ownership are not monolithic, yet digital humanities work often expects the replication of narrow ideas of such. Drawing on the growing body of scholarship that situates the digital humanities in a broad global context, this paper points to areas of tension within the field and posits ways that digital humanities practitioners might resist such moves to homogenize the field. Working within the framework of border studies, the paper considers how working across national barriers might further digital humanities work. Finally, ideas of ownership and/or copyright are unique to country of origin and, as such, deserve careful attention. While open access is appealing in many digital humanities pro- jects, it is not always appropriate, as work with indigenous cultural artifacts has revealed.

关键词： Digital humanities Global Borderlands Transnational

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Quiet in the nest:The nest environment attenuates song in a grassland songbird

引用

Avian Research 2023年第4期14卷 623-629页

作者： Sarah L.Dobney mikayla m.K.Bornais D.Ryan Norris amy E.m.Newman Heather Williams Stéphanie m.Doucet Daniel J.mennill Department of Integrative Biology University of WindsorWindsorOntarioN9B 3P4Canada Department of Integrative Biology University of GuelphGuelphOntarioN1G 2W1Canada Biology Department Williams CollegeWilliamstownMA01267USA

The nest environment may limit the ability of nest-bound birds to hear sounds from the outside *** vocal learning species,such as humans and songbirds,it is vital for young animals to hear the voices of conspecific animals early in *** songbirds,nest structure varies considerably across species,and the resulting impact on sound transmission may have consequences for vocal learning in *** this study,we tested the hypothesis that the nest environment attenuates song of Savannah Sparrows(Passerculus sandwichensis),grassland songbirds that build nests on the ground under cover of dense *** recorded live Savannah Sparrows singing at variable distances from 21 *** recorded songs using one microphone inside the nest(the typical position of a nestling)and another placed 1 m directly above the nest(a typical position of an adult).We found a substantial reduction in signal-to-noise ratio,where songs recorded inside the nest were an average of 11 dB lower than songs recorded directly above the *** estimate that the attenuation imposed by the nest reduced the maximum acoustic environment from 117.7 m(for recordings above the nest),to 78.6 m(for recordings within the nest),which is analogous to listening from a position 39.1 m farther away from the *** research estimated that song transmits up to 100 m in this species,so any adult male within 100 m of a young bird was previously considered a potential vocal *** reducing the nestling acoustic environment from 100 m to 78.6 m,the number of male tutors available to nestlings is reduced by an average of 27%.Given the growing evidence that song learning begins very early in life,future research on vocal development should account for how the structural properties of the natal environment affect the songs that nestlings hear.

关键词： Acoustic environment Nest environment Songbird Sound attenuation Vocal learning

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：