检索结果-南通市图书馆

Epidermal growth factor receptor pathway substrate 8 (Eps8) expression in maturing testis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2004年第3期6卷 195-203页

作者： Alain Wunsch Kai Strothmann Manuela Simoni Jorg Gromoll Eberhard Nieschlag c.Marc Luetjens Institute of Reproductive Medicine of the University D-48129 MunsterGermanyInstitute of Reproductive Medicine of the UniversityD-48129 MunsterGermanyInstitute of Reproductive Medicine of the UniversityD-48129 MunsterGermanyInstitute of Reproductive Medicine of the UniversityD-48129 MunsterGermanyInstitute of Reproductive Medicine of the UniversityD-48129 MunsterGermanyInstitute of Reproductive Medicine of the UniversityD-48129 MunsterGermany

Aim: Although epidermal growth factor receptors are expressed in the testes, whether they signal through epidermal growth factor receptor pathway substrate 8 (Eps8) is unknown. Here we evaluated the expression pattern of Eps8 in the maturing testis. Methods: The expression of Eps8 was analysed by Northern blotting, immunocy-tochemistry and Western blotting in primary Sertoli cell cultures and in testicular tissue of rodents. Results: Eps8 is specifically expressed in gonocytes, Leydig and Sertoli cells of the neonatal rats and in Leydig and Sertoli cells of the adult rats and mice. Although gonocytes express Eps8, no signal was found in prepubertal or mature spermatogonia and the expression level of Eps8 in Sertoli cells increases with age. No regulation of Eps8 expression in primary immature rat Sertoli cells by Follicle stimulating hormone (FSH) was detected by Western blotting. conclusion: Eps8 seems to be involved in the growth factor-controlled regulation of cell proliferation and differentiation in the seminiferous epithelium. Eps8 is a possible marker for gonocytes and in Sertoli cells it could be involved in crosstalk with other growth factor pathways.

关键词： gene expression isoform Sertoli cell gonocyte

Associations between aerobic and muscle-strengthening physical activity,sleep duration,and risk of all-cause mortality:A prospective cohort study of 282,473 ***

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2023年第1期12卷 65-72页

作者： Mitch J.Duncan Stina Oftedal christopher E Kline Ronald c.Plotnikoff Elizabeth G.Holliday School of Medicine&Public Health College of HealthMedicineand WellbeingThe University of NewcastleCallaghanNSW 2308Australia Priority Research centre for Physical Activity and Nutrition The University of NewcastleCallaghanNSW 2308Australia Department of Health&Human Development The University of PittsburghPittsburghPA 15261USA School of Education University of NewcastleCallaghanNSW 2308Australia

Purpose:To examine the joint associations between meeting guidelines for physical activity(PA)and sleep duration and all-cause mortality risk among ***:Participants were adults(n=282,473)aged 18-84 years who participated in the 2004-2014 *** Health Interview *** status was ascertained using the National Death Index through December ***-reported PA(Active:meeting both aerobic(AER)and muscle-strengthening(MSA)guidelines,AER only(AER),MSA only(MSA),or not meeting either AER or MSA(Inactive))and sleep duration(Short,recommended(Rec),or Long)were classified according to guidelines,and 12 PA-sleep categories were *** hazard ratios and 95%confidence intervals(95%cIs)for all-cause mortality risk were estimated using cox proportional hazards regression ***:A total of 282,473 participants(55%females)were included;18,793 deaths(6.7%)occurred over an average follow-up of 5.4 *** to the Active-Rec group,all other PA-sleep groups were associated with increased mortality risk except for the Active-Short group(hazard ratio=1.08;95%cI:0.92-1.26).The combination of long sleep with either MSA or Inactive appeared to be *** a given sleep duration,mortality risk progressively increased among participants classified as AER,MSA,and *** each activity level,the mortality risk was greatest among adults with long ***:Relative to adults meeting guidelines for both PA and sleep duration,adults who failed to meet guidelines for both AER and muscle strengthening PA and who also failed to meet sleep duration guidelines had elevated all-cause mortality *** results support interventions targeting both PA and sleep duration to reduce mortality risk.

关键词： Activity-sleep patterns All-cause mortality Prospective Resistance training

An unsupervised learning approach to study synchroneity of past events in the South china Sea

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2019年第3期13卷 628-640页

作者： Kevin c. Tse Hon-chim chiu Man-Yin Tsang Yiliang Li Edmund Y. Lam Department of Earth Sciences The University of Hong KongPokfulamHong KongChina Department of Geography and centre for Geo-computation Studies Hong Kong Baptist UniversityKowloon TongHong KongChina Department of Earth Sciences University of TorontoCanada Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong KongChina

Unsupervised machine learning methods were applied on multivariate geophysical and geochemical datasets of ocean floor sediment cores collected from the South china Sea. The well-preserved and continuous core samples comprising high resolution cenozoic sediment records enable scientists to carry out paleoenvironment studies in detail. Bayesian age-depth chronological models constructed from biostratigraphic control points for the drilling sites are applied on cluster boundaries generated from two popular unsupervised learning methods: K-means and random forest. The unsupervised learning methods experimented have produced compact and unambiguous clusters from the datasets, indicating that previously unknown data patterns can be revealed when all variables from the datasets are taken into account simultaneously. A study of synchroneity of past events represented by the cluster boundaries across geographically separated ocean drilling sites is achieved through converting the fixed depths of cluster boundaries into chronological ranges represented by Gaussian density plots which are then compared with known past events in the region. A Gaussian density peak at around 7.2 Ma has been identified from results of all three sites and it is suggested to coincide with the initiation of the East Asian monsoon. contrary to traditional statistical approach, a priori assumptions are not required for unsupervised learning, and the clustering results serve as a novel data-driven proxy for studying the complex and dynamic processes of the paleoenvironment surrounding the ocean sediment. This work serves as a pioneering approach to extract valuable information of regional events and opens up a systematic and objective way to study the vast global ocean sediment datasets.

关键词： machine learning ocean sediments unsupervised classification

Implementing the Node Based Smoothed Finite Element Method as User Element in Abaqus for Linear and Nonlinear Elasticity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

computers, Materials & continua 2019年第8期61卷 481-502页

作者： S.Kshrisagar A.Francis J.J.Yee S.Natarajan c.K.Lee Integrated Modelling and Simulation Lab Department of Mechanical EngineeringIndian Institute of Technology MadrasChennai600036India The Department of Architectural Engineering Dong-A UniversityS04-0302Engineering 237Nakdongdaero 550beon-gilSaha-guBusan49315Korea National Research center for Disaster-free&Safe Ocean city Dong-A UniversityS04-0311-3Engineering 237Nakdong-daero 550beon-gilSaha-guBusan49315Korea

In this paper,the node based smoothed-strain Abaqus user element(UEL)in the framework of finite element method is *** basic idea behind of the node based smoothed finite element(NSFEM)is that finite element cells are divided into subcells and subcells construct the smoothing domain associated with each node of a finite element cell[Liu,Dai and Nguyen-Thoi(2007)].Therefore,the numerical integration is globally performed over smoothing *** is demonstrated that the proposed UEL retains all the advantages of the NSFEM,i.e.,upper bound solution,overly soft stiffness and free from locking in compressible and nearly-incompressible *** this work,the constant strain triangular(cST)elements are used to construct node based smoothing domains,since any complex two dimensional domains can be discretized using cST *** additional challenge is successfully addressed in this *** efficacy and robustness of the proposed work is obtained by several benchmark problems in both linear and nonlinear *** developed UEL and the associated files can be downloaded from https://***/nsundar/NSFEM.

关键词： Smoothed finite element method(SFEM) node based SFEM(NSFEM) linear and nonlinear elasticity Abaqus UEL(user elements) compressible and nearlyincompressible materials

Anchor Vertex Selection for Enhanced Reliability of Traffic Offloading Service in Edge-Enabled Mobile P2P Social Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of communications and Information Networks 2020年第2期5卷 217-224页

作者： Hengda Zhang Xiaofei Wang Hao Fan Taotao cai Jianxin Li Xiuhua Li Victor c.M.Leung college of Intelligence and computing Tianjin UniversityTianjin 300350China School of Information Technology Deakin UniversityMelbourne 3217Australia School of Big Data and Software Engineering Chongqing UniversityChongqing 401331China Department of Electrical and computer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

As the rapid growth of mobile social networks,mobile peer-to-peer(P2P)communications and mobile edge computing(MEc)have been developed to reduce the traffic load and improve the computation capacity of cellular ***,the stability of social network is largely ignored in the advances of P2P and MEc,which is related to the social relations between *** plays a vital role in improving the efficiency and reliability of traffic offloading *** this paper,we integrate an edge node and the nearby P2P users as a mobile P2P social network and introduce the problem of adaptive anchored(k,r)-core to maintain the stability of multiple mobile P2P *** aims to adaptively select and retain a set of critical users for each network,whose participation is critical to overall stability of the network,and allocate certain resource for them so that the maximum number of users of all networks will remain engaged and the traffic of cellular network can be *** called the retained users as anchor *** address it,we devise a peer-edge-cloud framework to achieve the adaptive allocation of *** also develop a similarity based onion layers anchored(k,r)-core(S-OLAK)algorithm to explore the anchor *** results based on a real large-scale mobile P2P data set demonstrate the effectiveness of our method.

关键词： traffic offloading service mobile P2P communications mobile edge computing anchored k-core problem adaptive allocation

cloud condensation Nuclei over the Bay of Bengal during the Indian Summer Monsoon

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2018年第2期35卷 218-223页

作者： D. M. cHATE R. T. WAGHMARE c. K. JENA V. GOPALAKRISHNAN P. MURUGAVEL Sachin D. GHUDE Rachana KULKARNI P. c. S. DEVARA Indian Institute of Tropical Meteorology Pune 411008 India Marine Earth and Atmospheric Science North Carolina State University Raleigh NC 27695 USA Amity centre for Ocean-Atmospheric Science and Technology (AcOAST) & Amity centre for Environmental Science and HeaLSTh (AcESH) Amity University Haryana Gurgaon-Manesar 122 413 India

The first measurements of cloud condensation nuclei （ccN） at five supersaturations were carried out onboard the research vessel ＂Sagar Kanya＂（cruise SK-296） from the south to the head-bay of the Bay of Bengal as part of the continental Tropical convergence Zone （cTcZ） Project during the Indian summer monsoon of 2012. In this paper, we assess the diurnal variation in ccN distributions at supersaturations from 0.2% to 1% （in steps of 0.2%） and the power-law fit at supersaturation of 1%. The diurnal pattern shows peaks in ccN concentration （NccN） at supersaturations from 0.2% to 1% between 0600 and 0700 LST （local standard time, UTc＋0530）, with relatively low concentrations between 1200 and 1400 LST, followed by a peak at around 1800 LST. The power-law fit for the ccN distribution at different supersaturation levels relates the empirical exponent （k） of supersaturation （%） and the Nccy at a supersaturation of 1%. The Nccy at a supersaturation of 0.4% is observed to vary from 702 cm-3 to 1289 cm-3, with a mean of 961 ＋ 161 cm-3 （95% confidence interval）, representing the ccN activity of marine air masses. Whereas, the mean Nccy of 1628 ＋ 193 cm-3 at a supersaturation of 1% is higher than anticipated for the marine background. When the number of ccN spectra is 1293, the value of k is 0.57 ± 0.03 （99% confidence interval） and its probability distribution shows cumulative counts significant at k ≈ 0.55 ± 0.25. The results are found to be better at representing the features of the marine environment （103 cm-3 and k ≈ 0.5） and useful for validating ccN closure studies for Indian sea regions.

关键词： cTcZ Bay of Bengal monsoon, ccN supersaturation power-law relationship

Estimation of Wheat Area in córdoba, Argentina, with Multitemporal NDVI Data of SPOT-Vegetation

在线全文

学校读者我要写书评

暂无评论

International Journal of Geosciences 2013年第10期4卷 1355-1364页

作者： A. c. de la casa G. G. Ovando Fac. de ciencias Agropecuarias Universidad Nacional de Córdoba Córdoba Argentina

Determining the area occupied by a crop is a prerequisite for estimating agricultural production in a region, and such information at present can be generated from satellite remote sensing systems. This study uses multitemporal NDVI images of SPOT-VEGETATION with a 1 km spatial resolution to estimate the wheat area in córdoba Province, Argentina, and to assess 2 generic digital classification procedures based on crop phenological behavior. The characteristic Phenology Behavior Method (cPBM) uses the contrast each year between typical values of NDVI variation in the wheat crop season and those of the area not occupied by active vegetation;while the other procedure, the Reference curve Method (RcM), assesses the correspondence in each pixel between the observed sequence of NDVI from seeding to physiological maturity, compared with 4 curves of reference. The cPBM 2 procedure, which uses the amplitude of NDVI between sowing and heading (ampsh), produces estimates that correlate better with the observed record, with approximately 70% (P s the state reports at about 5%. On the other hand, RcM using curve 1 explains 50% (P sh in the model with the minimum NDVI during physiological maturity stage (minpm) produced a deterioration of estimation, with R2 reduced to 0.37 (P 2 of 0.61 (P ed the linear relationship between observed and estimated with a slope that did not approach 1. RcM classification models reach a predictive performance similar to that shown in Río Segundo, with R2 values close to 0.50

关键词： Wheat crop Area NDVI classification Methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

硅基催化结构合成的策略(英文)

催化学报 2008年第11期29卷 1187-1192页

作者： Harold H. KUNG Mayfair c. KUNG chemical and Biological Engineering Department Northwestern University

Two approaches to synthesize silicon-based catalytic structures that aim at capturing the properties and functionalities of natural enzymes are described in this brief review:unit-by-unit synthesis of macromolecular units and templating/imprinting synthesis of nanocages. The unit-by-unit approach mimics the peptide synthesis method,offers atomic control of the structure,but is inefficient in synthesizing large structures such as nanocages. The templating/imprinting method is more suitable for nanocages at the sacrifice of atomic control,and the nanocages obtained are shown to possess properties exhibited by enzyme cavities.

关键词：合成工艺化学结构催化过程催化剂

Hepatitis c virus antibodies among transfused children with sickle cell anaemia at University of Ilorin Teaching Hospital

在线全文

学校读者我要写书评

暂无评论

Open Journal of Pediatrics 2013年第3期3卷 195-200页

作者： c. E. Onuchukwu A. Ojuawo S. Kolade Ernest Department of Paediatrics and child Health Federal Medical Centre Keffi Nigeria Department of Paediatrics and child Health University of Ilorin Teaching Hospital Ilorin Nigeria

Background: Hepatitis c is an infectious disease of the liver caused by the Hepatitis c virus (HcV) resulting to a chronic Hepatitis. chronic HcV infection constitutes a serious health challenge in places where prevalence is substantial. In Nigeria, there is a high risk because donor blood is not routinely screened for HcV. Patients with sickle cell anaemia (ScA) are considered a subset of the population at higher risk of acquiring the virus, due to their frequent needs for transfusion of blood and its products. However, the magnitude of HcV infection has not been adequately measured in our general population and specific data on HcV in ScA patients are scanty, hence a prospective case controlled study to determine the prevalence of HcV antibodies in transfused ScA patients attending the sickle cell anaemia clinic in the University of Ilorin Teaching Hospital (UITH), Ilorin was taken. Objective: To determine the prevalence of Hepatitis c virus antibodies among transfused children with ScA in Ilorin. Subjects and Method: Eighty two transfused ScA children aged 6 months to 14 years were recruited consecutively from February 2008 to January 2009 while eighty four non transfused ScA children of the same age range recruited over the same period served as controls. Hepatitis c virus antibody screening was done using a second generation ELISA method. Results: The overall prevalence of HcV antibody was 3.0%, while it was 3.7% and 2.4% in the transfused and non transfused ScA patients respectively (χ2 = 0.23, p = 0.68). The patients were also comparable across the social class when subcategorized into high and low social class (χ2 = 0.37, p = 1.00 (subjects), χ2 = 0.42, p = 1.00 (controls). conclusion: The prevalence of Hepatitis c virus anti- bodies in transfused ScA patients is low. The difference in prevalence between transfused and nontransfused ScA patient was not statistically significant. This was cautiously interpreted due to the hospital based premise of the work. T

关键词： Hepatitis c Virus Sickle cell Anaemia Blood Transfusion