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The duration of sociosexual behaviors in male meadow voles Microtus pennsylvanicus varies before, during, and after copulation

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Current Zoology 2011年第1期57卷 43-49页

作者： Ashlee A. VAUGHN Daniel A. FERKIN Javier delBARCO-TRILLO Michael H. FERKIN Department of Biological Sciences The University of Memphis Memphis TN 38152 USA Department of Evolutionary Anthropology Duke University Box 90383 Durham NC 27708 USA

The behaviors that surround copulation are characterized as sociosexual behaviors. These behaviors displayed by males that are directed at females may include allogrooming, wrestling, chasing, approach, and time spent together. The data supported the hypothesis that the duration of sociosexual behaviors differs during the pre-copulatory, peri-copulatory, and post-copulatory phases of the mating bout in meadow voles. Voles spent more time approaching conspecifics during the pre- and peri-copulatory phases than during the post-copulatory phase. Voles spent more time allogrooming, wrestling, and chasing during the pre-copulatory phase than during the peri- and post-copulatory phases. Voles spent similar amounts of time together during the pre-, peri-, and post-copulatory phases. The data suggest that sociosexual behaviors displayed by males may be involved in set- ring the pace and temporal components of the mating bout. During the pre-copulatory phase particular behaviors by male voles may attract females, during the peri-copulatory phase some of these behaviors may stimulate or motivate the female to mate, and during the post-copulatory phase certain behaviors may prepare the male to mate again

关键词： Copulatory behavior Meadow voles Odors Sociosexual behavior

On the State of Stress in the Growth Plate under Physiologic Compressive Loading

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Open Journal of Biophysics 2014年第1期4卷 13-21页

作者： Jie Gao John L. Williams Esra Roan Department of Mechanical Engineering Biomedical Engineering The University of Memphis Memphis USA

The growth plate is a thin layer of cartilage sandwiched between epiphyseal and metaphyseal bone and is the location of active bone growth during childhood. It is subjected to large compressive and shear forces while protecting its resident chondrocytes from damage. We believe that computational modeling can help us better understand how the macro-scale loads are transmitted to micro-scale stresses and strains within the growth plate cartilage. As a first step in this process we analyzed the mechanical response of compression experiments performed on bovine bone/growth plate/bone samples. We endeavored to estimate the modulus of elasticity of the growth plate itself by simulating the compression experiments of these specimens using the finite element method. It is shown that when the growth plate in the compression specimens was modeled as a flat layer, the state of stress in the cartilage was triaxial and non-uniform with the hydrostatic stress being much greater than the octahedral shear stress over most of the central region of the growth plate test samples. The computational models accounted for variations in the average cartilage thickness, the non-uniaxial, non-uniform and triaxial state of stress in the thin cartilage layer, and for the estimated extrinsic compliance resulting from compression of the variable heights of bone on either side of the growth plate cartilage. However, due to lack of information on the internal structure of each sample, the models did not account for the variations in the non-flat topography of the growth plates. The models also did not include the calcified cartilage layer. Further model development is recommendedin order to determine the degree to which accounting for the complex growth plate topography influences the predicted cartilage modulus of elasticity.

关键词： Growth Plate Physis Cartilage Mechanical Properties Finite Element Analysis

The Change of Land Use/Cover and Characteristics of Landscape Pattern in Arid Areas Oasis： An Application in Jinghe, Xinjiang

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Geo-Spatial Information Science 2010年第3期13卷 174-185页

作者： TASHPOLAT·Tiyip Hsiang-te KUNG Department of Resources and Environment Sciences Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Department of Earth Sciences Memphis University

This paper uses 3S technology in macroscopic. Combining the integrated technology of ecological quantity analytical method with GIS technology through ArcGIS and Fragstats, the authors study the images of 1972, 1990, 2001, and 2005 and obtained land use data in Jinghe County. Then, the change of land use/cover and landscape pattern had been analyzed in the Jinghe County of Xinjiang. The conclusions were as follows: (1) The trend of LUCC is that the area of oasis expands slowly in nearly 33 years between 1972 to 2005 in Jinghe County. (2) The water area is mainly influenced by Ebinur Lake, so the area expands a little in this period. (3) The area of salinization-land expands at first and reduces later. The area of sand land decreases and the other land class increases, while the probability of transfer is always high. (4) Landscape change is also obvious throughout the decades. Overall, landscape density increases, the largest path index decreases at first and expends later, the weight area index decreases, and the shape of landscape becomes regulated. The nearest distances, the degrees of reunite, and outspread decreases. It shows that the connection of the main path in 1972 is better than 2005, wherein the patch becomes more complex. From the changes of Shannon’s Diversity Index and Shannon’s Evenness Index, we know that the diversity of landscape and the Interspersion Juxtaposition Index increase. The degree of diversity landscape and fragmentation increase also shows that the land uses become more complex. All in all, it is essential to intensify the spatial relationships among landscape elements and to maintain the continuity of landscape ecological process and pattern in the course of area expansion.

关键词： arid area oasis land use/cover change (LUCC) landscape change Jinghe County

Can science save the giant panda (Ailuropoda melanoleuca)? Unifying science and policy in an adaptive management paradigm

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Integrative Zoology 2011年第3期6卷 290-296页

作者： Ronald R.SWAISGOOD Fuwen WEI William J.MCSHEA David E.WILDT Andrew J.KOUBA Zejun ZHANG San Diego Zoo Institute for Conservation Research EscondidoCaliforniaUSA Institute of Zoology Chinese Academy of ScienceBeijingChina Conservation&Research Center Smithsonian’s National Zoological ParkFront RoyalVirginiaUSA memphis Zoo MemphisTennesseeUSA Institute of Rare Animals and Plants China West Normal UniversityNanchongSichuanChina

The giant panda(Ailuropoda melanoleuca David,1869)is an iconic species for global conservation,yet field research has only recently advanced to the point where adaptive management is ***,we review recent developments in giant panda conservation science and propose a strategic plan for moving panda conservation *** of scientific,funding,political,and logistical hurdles,few endangered species management programs have embraced adaptive management,wherein management decisions are shaped iteratively by targeted scientific *** threats,such as habitat destruction,anthropogenic disturbance and fragmented nonviable populations,need to be addressed simultaneously by researchers,managers and policy-makers working in concert to understand and overcome these obstacles to species *** the backing of the Chinese Govern-ment and the conservation community,the giant panda can become a high-profile test species for this much touted,but rarely implemented,approach to conservation management.

关键词： adaptive management conservation policy endangered species giant panda strategic conservation plan

维生素A酸在银溶胶液中的表面增强拉曼散射光谱

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光谱学与光谱分析 2004年第11期24卷 1376-1378页

作者：王玉 LI Ying-sing 张正行安登魁江苏省药品检验所 Department of Chemistry University of MemphisMemphisTN38152USA 中国药科大学

将水中不溶的药物维生素A酸(VAA)溶于氯仿中,然后与银溶胶液混合,振摇,取静置分层后的上层溶胶液测定表面增强拉曼光谱,氯仿在银溶胶中无表面增强效应,不干扰维生素A酸的测定。与固体粉末拉曼光谱相比较,对光谱峰归属进行了解释。通过分... 详细信息

将水中不溶的药物维生素A酸(VAA)溶于氯仿中,然后与银溶胶液混合,振摇,取静置分层后的上层溶胶液测定表面增强拉曼光谱,氯仿在银溶胶中无表面增强效应,不干扰维生素A酸的测定。与固体粉末拉曼光谱相比较,对光谱峰归属进行了解释。通过分析CO伸缩振动带和ν(COO)振动峰明显增强的现象,讨论了维生素A酸分子在银颗粒表面可能的吸附取向,并推断维生素A酸在银表面的吸附发生在COO-基团。以维生素A酸表面增强拉曼光谱在1583cm-1处的峰强度对浓度进行线性回归,求得线性回归方程Y=10×108+95585,在10×10-6～50×10-5mol·L-1范围呈良好的线性关系,最小检测限为10×10-7mol·L-1。结果表明,维生素A酸表面增强拉曼光谱峰数量少,灵敏度高,是定量分析痕量维生素A酸的很好方法。

关键词：维生素A酸表面增强拉曼光谱药物检测限表面增强拉曼散射氯仿定量分析银溶胶伸缩振动基团

Recent advances on the role of long non-coding RNAs in Alzheimer’s disease

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Neural Regeneration Research 2020年第12期15卷 2253-2254页

作者： Kyle Doxtater Manish K.Tripathi Mohammad Moshahid Khan Department of Pharmaceutical Sciences University of Tennessee Health Science CenterMemphisTNUSA Department of immunology and Microbiology University of Texas Rio Grande ValleyMcAllenTXUSA Department of Neurology College of MedicineDivision of Rehabilitation Sciences and Department of Physical TherapyCollege of Health ProfessionsUniversity of Tennessee Health Science CenterMemphisTNUSA

Dementia is a progressive cognitive impairment that affects the activities of daily ***’s disease (AD) is the most common form of the dementia worldwide accounting for 60-80%of all dementia *** an estimated cost exceeding$290 billion in the USA,understanding and development of future therapeutic strategies is *** this perspective,we will be examining the current thinking of AD research and therapeutic strategies,while proposing a possible new direction for diagnosis,understanding,and treatment targets.

关键词： Alzheimer diagnosis exceeding

Probing the Ribosome Assembly:Insight from Ribosomal Proteins

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Probing the Ribosome Assembly:Insight from Ribosomal Protein...

Use of a Standing Desk Increases Energy Expenditure in Obese but Not Normal Weight Subjects

中国化学会2014年大分子体系理论、模拟与计算研讨会

作者： Yongmei Wang Brittany B.Lott Department of Chemistry The University of MemphisMemphisTennessee 27251USA

Ribosomes are complex cellular machines that synthesize new proteins in the *** accurate and efficient assembly of ribosomal proteins(r-proteins)and ribosomal RNA(r RNA)to form a functional ribosome is important for cell growth,metabolic reactions,and other cellular *** assembly has been an active research topic for many years because understanding the assembly mechanisms can provide insight into protein/RNA recognitions that are important in many other cellular *** and computational studies thus far have greatly improved our understanding of assembly,yet many questions remain unanswered regarding the complex behaviors of r-proteins and r RNA during the *** further understand ribosome assembly,we have computationally studied the sequences,structures,and dynamic properties of r-proteins from the 30S subunit and their relationships to RNA *** found a statistically greater amount of positively charged residues in r-proteins compared to other housekeeping proteins and observe a high level of charged interactions between r-proteins and r RNA in the assembled *** also detect a significant correlation between the overall flexibility of a protein and the number of contact points it makes with its r RNA binding *** residues contacting with r RNA are observed to be more mobile in solution when compared to the non-contacting *** also describe common modes of structural dynamics,revealing likely conformational changes the proteins make prior to binding,and how they relate to possible binding mechanisms used during *** computational investigations shed new insight on the ribosome assembly process but at the same time reveal significant challenges in understanding ribosome assembly.

关键词： ribosome ribonuclear complex self-assembly

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Health 2018年第7期10卷 949-959页

作者： Nicholas J. G. Smith Matt Butawan Jade Caldwell Richard J. Bloomer Cardiorespiratory/Metabolic Laboratory School of Health Studies University of Memphis Memphis TN USA

Background: The use of standing desks has been associated with greater metabolic cost as compared to traditional seated desks. However, it is unclear as to the metabolic impact of standing desks in normal weight versus obese men and women. Methods: We compared the metabolic cost of using a standing and seated desk in 14 obese and 19 normal weight men and women. Subjects reported to the lab on a single occasion and participated in two, 30-minute sessions of standing and seated desk work (i.e., typing), in random order. Expired gases were collected during the 2-hour period and calorie expenditure was estimated using indirect calorimetry. Results: We noted a significant (p = 0.013) increase in energy expenditure of 7.4 kcal•30 minutes−1 (+14.7%) during standing as compared to seated for the obese group. No significant difference in energy expenditure was noted for the normal weight group (p = 0.674). A condition effect was noted for heart rate and diastolic blood pressure, with standing being significantly higher than seated for both variables (p 0.05). Conclusion: The use of a standing desk modestly increases energy expenditure in obese subjects but does not have the same effect in those of normal weight. It is unknown whether the increased energy expenditure would be maintained over time in the obese subjects/individuals, as they may adapt to the standing position. Moreover, if normal weight individuals choose a standing desk, they should do so for reasons unrelated to increased energy expenditure (e.g., improved spine health, greater feeling of productivity).

关键词： Metabolic Rate Standing Desk Energy Expenditure Workplace

Comparison of nutritional intake in US adolescent swimmers and non-athletes

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Health 2012年第10期4卷 873-880页

作者： Andy C. Collins Kenneth D. Ward Bridget Mirza Deborah L. Slawson Barbara S. McClanahan Christopher Vukadinovich College of Public Health East Tennessee State University Johnson City USA Department of Epidemiology & Cancer Control St Jude Children’s Research Hospital Memphis USA Department of Health and Sport Sciences The University of Memphis Memphis USA Division of Social and Behavioral Sciences School of Public Health The University of Memphis Memphis USA memphis USA

Swimming is a very popular sport among adolescents in the US. Little is known about the diet of competitive adolescent swimmers in the US but data from other countries indicate several inadequacies, including excessive intake of fat and lower than recommended intake of carbohydrate and several micronutrients that may affect athletic performance and bone accrual. We assessed usual diet, using a food frequency questionnaire and calcium checklist, among 191 adolescent males and females [91 swimmers (mean 13.7, s = 2.5 years) and 100 non-athletes (mean 14.4, s = 2.8 years)]. For both males and females, swimmers and non-athletes generally had similar average intakes of macro- and micro-nutrients, including higher than recommended amounts of total fat (36%) and saturated fat (12%), and inadequate amounts of calcium, vitamin D, and daily servings of fruits, vegetables, grains, and dairy products. This first study of nutritional intake among adolescent swimmers in the US suggests that dietary habits of adolescents who swim competitively may jeopardize optimal athletic performance and place them at risk for future chronic diseases, including osteoporosis.

关键词： Nutrition Dietary Intake Swimming Bone Health