188 research outputs found

    Prevalence and risk factors associated with HIV infection among female sex workers in Mengzi City

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    目的了解云南省蒙自市女性性工作者(FSWs)艾滋病病毒(HIV)的感染情况及HIV感染相关危险因素,为制定艾滋病防控策略和行为干预提供依据。方法于2010年10-11月采用方便抽样的方法,招募云南省红河州蒙自市娱乐场所FSWs,调查其社会人口统计学、行为学、HIV/AIDS知识以及生殖健康状况,并采集静脉血进行HIV血清学检测,分析FSWs人群HIV感染率及其危险因素。结果本次共调查423名FSW,HIV抗体阳性19人,HIV抗体阳性率为4.5%。最近一个月与客人发生性行为时坚持使用安全套的比例为87.0%。多因素分析显示,与HIV感染相关的危险因素为在低档性服务场所服务(校正OR=10.0,95%CI:3.77~26.67,P<0.001)和从事性服务时间≥2年(校正OR=3.8,95%CI:1.39~10.20,P=0.01)。结论蒙自市FSWs有较高的HIV感染率,在低档性服务场所服务及从事性服务时间长是HIV感染的危险因素,需针对低档和中高档FSWs的危险行为特征分别实施不同的干预措施,控制HIV的传播流行。Objective To explore the prevalence and risk factors of HIV infection among female sex workers( FSWs) in Mengzi City,Yunnan Province,so as to provide scientific evidence for formulating HIV prevention and control strategy and behavior intervention measures. Methods From October to November,2010,the convenience sampling method was used to recruit FSWs in the entertainment venues in Mengzi City in Yunnan Province to investigate their demographic information,sexual behavior,HIV / AIDS knowledge and reproductive health status. Venous blood was collected to test HIV. The prevalence and risk factors of HIV infection were analyzed. Results Totally,423 FSWs were recruited,among whom 19 were confirmed to be HIV antibody positive and the prevalence rate of HIV was 4. 5%. The proportion of the FSWs with consistent condom use when having sex with clients in the last month was 87. 0%. Multivariate logistic analysis indicated that the factors associated with HIV infection were working in low level sex work venues( adjusted OR = 10. 0,95% CI: 3. 77-26. 67,P < 0. 001) and time engaged in sexual work for 2 years or more( adjusted OR = 3. 8,95% CI: 1. 39-10. 20,P = 0. 01). Conclusions The prevalence of HIV is high among female sex workers in Mengzi City. FSWs who work in low-grade sex work venues and engage in sexual work for long time are at higher risk of HIV infection. Intervention measures targeted at dangerous behavior of FSWs working in different levels of sex work venues should be carried out to control the spread and prevalence of HIV / AIDS.国家“十一五”重大专项(2008ZX10001-003

    全参数全约束优化对钢筋混凝土框架结构设计的造价分析

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    目前的优化设计一般是将参数简化为一维问题或多维问题,或为全参数优化设计,但约束条件不够充分.针对这些不足,本文建立了更全面的符合工程设计的全参数全约束优化设计模型,利用MATLAB中的fmincon函数进行寻优计算,它可以同各种结构设计软件链接进行参数优化,如本文算例采用了中国建筑设计研究院开发的PKPM软件中已有的内力计算功能.最后,通过算例将各参数对造价影响程度进行分析比较,得出了定性及定量的结论,优化后的结构造价降低显著.与当前的钢筋混凝土框架结构优化设计相比,本文具有较强的实用性、寻优计算快捷等优点

    束缚和异氟烷麻醉对大鼠心率变异性及HPA轴影响的比较

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    目的为了观察束缚固定和异氟烷(流量:0.8 L,浓度:1.5%)麻醉状态中大鼠的心率变异性的变化;并通过比较9天每天30 min束缚干预和异氟烷麻醉对大鼠的体重、痛阈以及与HPA轴相关激素的影响,来评估长期使用异氟烷麻醉和束缚固定对大鼠应激程度的影响,选择更适宜的大鼠固定方法,为基础医学的实验方法提供重要的参考。方法 SD大鼠随机分为3组:空白组,束缚组,异氟烷麻醉组。急性实验通过记录大鼠心电图15 min,观察束缚固定和异氟烷麻醉情况下大鼠心率,心率变异性的变化。慢性实验中比较连续干预9天(30 min/d)前后3组大鼠体重、痛阈变化以及与应激状态相关激素含量的变化。结果 1)急性试验:与空白组大鼠相比,束缚干预和异氟烷麻醉均造成大鼠心率显著增加,具有统计学意义(P 0.05)。结论以上结果提示:低浓度的异氟烷造成麻醉中大鼠心率增加,心率变异性下降,产生以交感兴奋为主的自主神经功能状态改变。多次束缚固定易造成大鼠HPA轴激活,产生慢性应激的效应。在长期需要固定动物的实验中,与束缚固定相比异氟烷麻醉是更好的固定方法。国家自然科学基金(81674083

    考虑分布式再生能源和储能的主动配电网可靠性评估

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    随着主动配电网技术的逐步发展和应用,针对主动配电网的各项评估技术也需要进一步研究。由于主动配电网在网络结构、潮流流向等方面与传统配电网有很大区别,因此针对主动配电网的评估方法也与传统配电网不同,提出了一种考虑分布式再生能源和储能的主动配电网可靠性评估方法。首先运用蒙特卡洛模拟法进行系统状态选择,再基于不同网络类型,采用改进的前推回代潮流计算方法进行潮流计算与潮流平衡调整,进而计算各项评估指标,获取综合评估值。通过对9个方案进行可靠性评估,验证了所提方法的有效性

    基于系统可靠性的主动配电网置信容量评估

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    评估主动配电网的置信容量,可以充分利用新能源,为主动配电网的优化配置提供有效参考。以新增电源的有效载荷能力表征主动配电网的置信容量,建立基于等可靠性指标的评估模型。在蒙特卡..

    基于并行小种群差分进化算法的水火电力系统短期优化调度

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    为解决水火电力系统短期发电优化调度中存在的问题,提出基于MPI平台的并行小种群差分进化算法。该算法将进化种群分为若干个小种群(单个种群规模为3~10个),每个进化种群由不同的CPU进程独立执行差分进化算法,并在种群间引入集合、分散操作以协调各小种群的寻优过程;为降低小种群初始化和进化过程中多样性的损失,引入正交化初始化方法和种群重构技术;最后以典型案例验证了算法的有效性。结果表明,该方法在求解精度、收敛速度和求解耗时上均较有竞争力。国家自然科学基金项目(61403321);;广东省自然科学基金项目(2014A030310003

    基于可见光与近红外遥感反射率关系的藻华水体识别模式

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    极轨气象卫星AVHRR红光波段(波段1,波长580~680nm)和近红外波段(波段2,波长720~1100nm)的水体遥感反射率关系函数Rrs(2)-1=α0Rrs(1)-1+g-1(1?α0)中,参数α0=(bb(1)/bb(2))(a(2)/a(1))对叶绿素浓度敏感且相对独立于浊度,以1.6<α0<5.6和0.01<Rrs(2)/g<0.2为判据,可以实现叶绿素浓度为64~256μg/L的近海藻华水体识别.在2003年6月闽江口藻华水体的AVHRR遥感信息识别基础上,进行了该识别模式与传统的单波段模式,以及与比值法、NDVI法、差值法等双波段模式的比较,建议将该识别模式发展为近海藻华水体遥感的普适模式

    Analysis of Epistatic and QE Interaction Effects of QTLs for Grain Shape in Rice

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    本研究利用基于明恢86x佳辐占水稻重组自交系(rECOMbInAnT InbrEd lInE,rIl)构建的SSr遗传图谱,总标记数为131。联合两季的稻米粒长(gl)、粒宽(gW)、长宽比(l/W)表型数据,应用混合线性模型方法进行QTl定位,并作加性效应、上位效应以及加性QTl、上位性QTl与环境(QTl-by-EnVIrOnMEnT,QE)的互作效应分析。检测到粒长、粒宽和长宽比的加性效应QTlS分别为6个、4个和4个,贡献率分别为23.67%、21.41%和25.78%;检测到8对粒长的上位性QTlS,5对粒宽的上位性QTlS,2对长宽比的上位性QTlS,贡献率分别为16.75%、22.36%和7.55%;环境互作检测中,发现共有9个加性QTlS和7对上位性QTlS与环境发生了互作。结果表明,上位效应在粒形性状的遗传与加性效应一样起了重要作用,环境互作效应对粒形性状有一定的影响。A linkage map consisting of 131 markers was constructed by using a recombinant inbred line (RIL) population derived from the indica-indica rice cross Minghui86×Jiafuzhan.Quantitative trait loci (QTLs) was located with a mixed linear model (QTLmapper1.6) based on the grain shape parameters such as grain length (GL), grain width (GW) and length-width ratio (L/W), and made analysis of additive effects, epistatic, and the interaction effects of QTL-by-environment (QE).Six, four and four QTLs were detected to have significant additive effects for GL, GW and L/W, and the contribution rate were 23.67%、21.41% and 25.78%, respectively.Eight, five and two pairs of epistatic QTLs with significant additive-by-additive (AA) interaction effects were identified for three traits, and the contribution rate were 16.75%、22.36% and 7.55%, respectively.Significant QE interactions were found for nine additive QTLs and seven pairs of epistatic QTLs.The results indicated that the epistatic effects played an important role on the inheritance of grain shape, and the environmental factor had certain effects on the three traits.福建省自然科学基金项目(X0750053);厦门大学科技创新计划项目(XDKJCX20063004)共同资

    Mapping QTLs for Rice Grain Shape with QTL×Environment Interactions and Epistatic Effects Analysis

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    利用广陆矮4号x佳辐占水稻重组自交系构建了SSr标记的遗传图谱.联合2007年和2008年获得的两组稻米粒长(gl)、粒宽(gW)、长宽比(l/W)数据应用混合线性模型方法进行QTl定位,并作加性效应、加性x加性上位互作效应以及加性QTl、上位性QTl与环境的互作效应分析.结果显示;(1)在加性效应分析中两个群体共检测到4个控制粒长的QTl,4个控制粒宽的QTl,5个控制长宽比的QTl,贡献率分别为13.81%、15.36%和16.29%.(2)在上位互作效应分析中两个群体共检测到2对控制粒长的互作QTl,1对控制粒宽的互作QTl,3对控制长宽比的互作QTl,贡献率分别为5.77%、2.59%和7.42%.(3)环境互作检测中,发现共有13个加性QTl和4对QTl的加性x加性上位性与环境产生了互作效应.结果表明,上位性效应和加性效应都影响稻米粒形遗传,QE互作效应也对粒形有着显著的影响.In this study,a recombinant inbred line (RIL) population derived from the indica-indica rice cross ‘Guangluai 4’בJiafuzhan’ was used in mapping of Quantitative trait loci (QTLs).Based on mixed linear model QTLmapper1.6,mapping was carried out for grain shape such as grain length (GL),grain width (GW) and length-width ratio (L/W) in rice in 2007 and 2008.QTLs were determined at the one-locus and two-locus levels,and QTL-by-environment (QE) interactions were analyzed.Four,four and five QTLs were detected to have significant additive effects for GL,GW and L/W,and the contribution rate were 13.81%,15.36% and 16.29%,respectively.Two,one and three pairs of epistatic QTLs with significant additive-by-additive (AA) interaction effects (epistatic effects) were identified for the three traits,and the contribution rate were 5.77%,2.59% and 7.42%,respectively.Significant QE interactions were found for thirteen QTLs with additive effects and four pairs of epistatic QTLs.The results indicated that the epistatic and additive effects played an important role on the inheritance of grain shape,and the environmental factor had significant effects on the three traits.国家863计划项目(2007AA10Z179);福建省科技计划重点项目(2008N0122);厦门大学科技创新项目(XDKJCX20063004

    苯丙乳液的共振散射光谱研究

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    用共振散射方法研究了苯丙乳液的稀释过程及其破乳过程,发现苯丙乳液的共振散射光谱在约381 nm和555 nm处出现2个共振散射峰;并且随着固含量的增加、Ca2+的加入量的减小及pH的增大,苯丙乳液的共振散射强度而增强
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