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Invasion genetics： lessons from a ubiquitous bird, the house sparrow Passer domesticus

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Current Zoology 2015年第3期61卷 465-476页

作者： Andrea l. lIEBl Aaron W. SCHREY Samuel C. ANDREW Elizabeth l.sheldon Simon C. GRIFFITH University of Exeter ComwaU Campus Penryn Cornwall TR10 9EZ UK Department of Biology Armstrong State University Savannah GA31419 USA Department of Biological Sciences Macquarie University Sydney NSW 2109 Australia

Following an introduction, non-native species are exposed to environments that differ from those found in their native range; further, as these non-native species expand beyond the site of introduction, they must constantly adapt to novel environments. Although introduced species are present across most ecosystems, few species have successfully established themselves on a truly global scale. One such species, the house sparrowPasser domesticus, is now one of the world’s most broadly distributed vertebrate species and has been introduced to a great part of its current range. To date, work on four continents suggests both genetic and phenotypic variation exists between native and introduced ranges. As such, house sparrows represent an excellent opportunity to study adaptations to novel environments and how these adaptations are derived. The global distribution of this species and the multiple independent introductions to geographically isolated sites allow researchers to ask questions regarding genetic variation and adaptation on a global scale. Here, we summarize the molecular studies of invasive house sparrows from the earliest work using allozymes through more recent work on epigenetics; using these studies, we discuss patterns of dispersal of this species. We then discuss future directions in techniques (e.g. next generation sequencing) and how they will provide new insight into questions that are fundamental to invasion biology. Finally, we discuss how continued research on the house sparrow in light of these genetic changes and adaptations will elucidate answers of adaptation, invasion biology, range expansion, and resilience in vertebrate systems generally.

关键词：表观遗传学生物入侵麻雀外来物种分子生物学生态系统脊椎动物动物物种

Investigation of serum calcium and vitamin D levels in superior semicircular canal dehiscence syndrome: A case control study

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Journal of Otology 2023年第1期18卷 49-54页

作者： Theofano Tikka Mohd Afiq Mohd Slim Trung Ton Anna sheldon louise J.Clark Georgios Kontorinis Department of Ear Nose and Throat SurgeryQueen Elizabeth University Hospital345 Govan RdGlasgowG514TFUnited Kingdom

Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in SSCD patients compared to a control ***: This was a prospective case-control study performed in a tertiary referral center, university teaching hospital in the UK. It included all new patients with SSCD seen in a dedicated skull base clinic over a 5-year period(2015-2019) compared to a gender and age matched control group. The main outcome of the study was adjusted calcium and Vitamin D levels between the two ***: A total of 31 SSCD patients were recruited with a matched number of control patients. The mean Vitamin D level on the SSCD group was 44.8 nmol/l(SD: 20.8) compared to 47.5 nmol/l(SD: 27.4) on the control group(p = 0.702). Mean Adjusted calcium level was 2.34 mmol/l(SD: 0.7) for SSCD compared to2.41 mmol/l(SD: 0.11) for controls(p = 0.01), being within normal limits for both the SSCD and the control ***: Our study did not identify a link between Vitamin D levels and presence of SSCD. Normal adjusted calcium values were found in both groups. Despite that a statistically significant lower calcium level was found in the SSCD group which could indicate that suboptimal levels of calcium may affect the micro-environment of the otic capsule at the SSC region.

关键词： Superior semicircular canal Dehiscence Calcium Vitamin D Metabolism

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21世纪世界家禽科学研究与发展方向

中国家禽 2000年第8期22卷 1-4页

作者： B.l.sheldon 张旭艳

家禽界在２１世纪的目标与挑战是满足全世界人们对动物蛋白的需求。解决这一问题的关键是需要生产更多的饲料粮──谷类、油子、荚豆类，给日益增长的家禽提供额外的饲料。在过去５０年里，已发生了很多改变：（１）２０世纪世界上５０... 详细信息

家禽界在２１世纪的目标与挑战是满足全世界人们对动物蛋白的需求。解决这一问题的关键是需要生产更多的饲料粮──谷类、油子、荚豆类，给日益增长的家禽提供额外的饲料。在过去５０年里，已发生了很多改变：（１）２０世纪世界上５０％的人从家禽技术革命中获益。（２）近来在遗传学、营养学、动物保健、舍饲及管理技术方面的提高，期待在生产中得到广泛应用。（３）目前在分子生物学、营养学、保健及繁殖方面的研究将在未来更广泛的应用。（４）目前在超过世界人口２５％的国家里仍然是小规模的、粗放的家禽生产体系。他们还不能实现现代的、集约化的畜牧生产，至少在５０年内是这样。只有全世界的业内人士共同关注，并提高生产效率，去迎接我们面前的挑战，提高职业主动性，从而引起全世界来共同关心，才能够实现我们的目标。

关键词：家禽科学研究发展方向 21世纪

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Heterologous expression of lamA gene encoded endo-β-1,3- glucanase and CO2 fixation by bioengineered Synechococcus sp. PCC 7002

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 115-122页

作者： Di li Swati Yewalkar Xiaotao Bi sheldon Duff Dusko Posarac Heli Wang layne A. Woodfin Jan-Hendrik Hehemann Sheila C. Potter Francis E. Nano School of Water Resources and Environment China University of Geosciences Beijing 100083 China Department of Chemical and Biological Engineering University of British Columbia Vancouve V6T 1Z3 Canada Department of Biochemistry and Microbiology University of Victoria Victoria V5Z 4H4 Canada

The gene for the catalytic domain of thermostable endo-β-1,3-glucanase （laminarinase） lamA was cloned from Thermotoga maritima MSB8 and heterologously expressed in a bioengineered Synechococcus sp. PCC 7002. The mutant strain was cultured in a photobioreactor to assess biomass yield, recombinant laminarinase activity, and CO2 uptake. The maximum enzyme activity was observed at a oH of 8.0 and a temoerature of 70℃. At a CO2 concentration of 5%, we obtained a maximum specific growth rate of 0.083 h^-1 a biomass productivity of 0.42 g· l^-1·d^-1 a blomass concentration of 3.697 g.l^-1 , and a specific enzyme activity of the mutant strain of 4.325 ***^- 1 dry mass. All parameters decreased as CO2 concentration increased from 5% to 10% and further to 15% CO2, except enzyme activity, which increased from 5% to 10% CO2. However, the mutant culture still 1 1 grew at 15% CO2 concentration, as reflected by the blomass productwlty （0.26 g.l .d ）, biomass concentration （2.416 g.l^- 1）, and specific enzyme activity （3.247 ***^-1 dry mass）.

关键词： Synechococcus sp. PCC 7002Thermotoga maritimalamA geneEndo-β-1 3-glucanaseCO2 fixation

ADVANCES IN ON-SITE VERIFICATION OF WATER FlOW METERS. THE INTEllIGENT APPlICATION OF ElECTROMAGNETIC INSERTION PROBES

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ADVANCES IN ON-SITE VERIFICATION OF WATER FLOW METERS. THE I...

Customized Online Aggregation &Summarization Tool for Environmental Rasters (COASTER)

The 12～(th) International Conference on Flow Measurement

作者： Alun l Thomas Robert sheldon Michael K Fray Peter Kobryn Information+Performance Services limited UK Information+Performance Services limited UK Information+Performance Services limited UK Severn Trent Water UK

＜正＞ The aim of this paper is to present recent advances which have been made in applying electromagnetic insertion probes to the verification of bulk supply water *** on laboratory work undertaken to define the baseline calibration of this type of insertion probe the authors illustrate how Traceability, Performance and Productivity have been dramatically improved through the use of intelligent software. Key elements that are discussed relate to the increasing demands of Water Industry Regulators for the introduction of Quality Management principles at the Site and Data level and how this has crucially influenced development of the applied technology. The on-site verification of bulk supply meters in the range 150mm and above is illustrated in detail and the current technique is contrasted with existing methods to show how major improvements have been achieved;delivering improved Traceability, uncertainty, performance and productivity. The authors will conclude by suggesting that through the use of the improved methods described the case for wider use of the electromagnetic insertion flowmeter, not only as the primary tool for verifying bulk water supply meters but also as a valid technique which can be applied in situations with poor hydraulics, can be made.

关键词： insertion probe verification water industry velocity profiling

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Journal of Geographic Information System 2012年第6期4卷 530-541页

作者： Daniel J. Weiss Katie Gibson Charles Sojka Jennifer W. sheldon Robert l. Crabtree Yellowstone Ecological Research Center Bozeman USA

The Customized Online Aggregation & Summarization Tool for Environmental Rasters (COASTER) system (***) was developed by Yellowstone Ecological Research Center (YERC) (***) in response to the information needs of end-user communities interested in decision-support for natural resource management. The purpose of COASTER is to greatly simplify the process of creating predictor datasets for research exploring environmental impacts driven by climate change, land-use activities, disturbance, and invasive spread. COASTER achieves this goal by providing users with a web-based system for processing environmental (gridded, raster) datasets, using a set of standardized functions, to create output customized to meet their analytical needs. In doing so, COASTER effectively translates large and cumbersome datasets into user-specified information useful for parameterizing statistical models and for visualizing spatial and temporal patterns within environmental datasets. The COASTER system currently contains over 10 terabytes of climate data from several sources. These datasets have daily temporal resolutions, spatial resolutions ranging from 1km to 330km, and temporal extents ranging from 30 to 64 years (1948-2011). COASTER datasets are primarily limited to North America, but gridded datasets from other regions can easily be added to the system. Variables within the climatic datasets available on COASTER include metrics quantifying temperature, precipitation, shortwave radiation, vapor pressure deficit, humidity, and wind conditions. Notable features of COASTER include a conceptually simple yet flexible set of functions capable of producing a wide range of outputs, a design applicable to many types of raster datasets, and results formatted for seamless integration within most GIS and remote sensing software packages.

关键词： Geographic Information Retrieval Online Application Remote Geographic Data Processing

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八、激光在肺科的应用

心肺血管病杂志 1983年第3期 19-20页

作者： R.l.sheldon 高立

一、引言(一)1900年H·G·wells在"世界大战"一书中写道:的武器将是一把热剑闪耀着光束的幽灵。(二)激光:是由放射线激发出放大的光。(三)1958年Townes及Showlow医生在Masers(微波)当火星侵犯这个世界时,他们杂志上发表了一篇文章,1951年

关键词：激光光子玻色子可见波

Movement Patterns of the Eastern Chipmunk (<i>Tamias striatus</i>) in Four Fragmented landscapes of Prince Edward Island, Canada

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Open Journal of Ecology 2020年第10期10卷 688-715页

作者： sheldon B. Opps leslie A. Cudmore Marina Silva-Opps Department of Physics University of Prince Edward Island Charlottetown Prince Edward Island Canada Office of the Vice President Academic and Research University of Prince Edward Island Charlottetown Prince Edward Island Canada Department of Biology University of Prince Edward Island Charlottetown Prince Edward Island Canada

The analysis of animal movement patterns can provide important information on animals’ responses to habitat features. In this study, the movement paths of eastern chipmunks (Tamias striatus) were examined in four landscapes, with different levels of habitat fragmentation, using either fluorescent powdering or spool-and-line tracking. Descriptions of the tree and ground vegetation communities were performed in the vicinity of the trail to obtain information on habitat use and habitat selection. Several key movement variables were calculated, including the total path length, net distance, fractal dimension, and radius of gyration. Despite statistically significant differences in some of the movement metrics between the four landscapes, the overall movement patterns were generically the same for all of chipmunk paths examined in this study. The data were compared to trends expected based on random or correlated random walks, as well as lévy-walk models. The mean squared net displacement did not support the correlated random walk predictions, except at smaller spatial scales, but overall demonstrated lévy-like super diffusive behaviour. lévy-like patterns were also confirmed from the move-length distributions that demonstrated truncated-tail power-law behaviour. Although this would suggest invariance of the movement patterns at all spatial scales studied, fractal analysis revealed at least two transitions in movement patterns at scales of around 2 and 5 m. The transition point at 2 m was negatively correlated with the density of small trees, while the transition at ~5 m was positively correlated with the spatial distribution of large trees. As the habitat-preference data showed that small trees are among the least preferred habitat component, while large trees were among the most preferred habitat, chipmunks are likely to alter their movement behaviour to avoid small trees, and attracted towards large trees possibly to avoid predators. Overall, we determined th

关键词： Fluorescent Powder Spool-and-line Fractal Radius of Gyration lévy Walk Correlated Random Walk Small Mammals Prince Edward Island

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李群与粒子物理学

世界科学 1987年第10期 39-39,56页

作者： sheldon l.Glashow 刘全慧

我在哈佛大学的研究生生活是与J.范·维勒克的著名课程物理学中的群论在1954年同时开始的。其课程的纪念物——有限小群的乘法表——仍然装饰在杰弗逊实验室的演讲厅中。在接下来的四分之一世纪中这一课程不断变化,经过了很多人(包括我... 详细信息

我在哈佛大学的研究生生活是与J.范·维勒克的著名课程物理学中的群论在1954年同时开始的。其课程的纪念物——有限小群的乘法表——仍然装饰在杰弗逊实验室的演讲厅中。在接下来的四分之一世纪中这一课程不断变化,经过了很多人(包括我)的手后变成了霍华德·乔基教授笔下的样子。很自豪我说服了霍华德来发表他有价值的讲稿。这课程的发展变化反映了物理学研究生们数学技能的增强;反映了李群对现代理论物理来讲

关键词：李群粒子物理学群论高能物理学物理学家基本粒子转动群