文冠果叶总皂苷的提取工艺优化及减肥降脂功效

【目的】优化文冠果叶总皂苷的提取工艺，并对其减肥降脂功效进行分析。【方法】采用单因素试验并结合Box-Behnken响应面法，对文冠果叶总皂苷的提取温度、液(mL)料(g)比、乙醇体积分数进行优化。采用高脂饲料喂养小鼠建立高血脂症模型，建模4周后，以奥利司他为阳性对照，分别采用高（200 mg/kg）、中（100 mg/kg）、低（50 mg/kg）剂量组文冠果叶总皂苷连续灌胃4周，检测小鼠血清总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白（LDL-C）和高密度脂蛋白（HDL-C）的浓度，分析不同剂量文冠果叶总皂苷对小鼠体内胰脂肪酶的抑制作用。【结果】文冠果叶总皂苷的最佳提取工艺条件为：提取温度60 ℃，乙醇体积分数70%，液(mL)料(g)比30∶1，此时文冠果叶总皂苷得率为4.952%。对小鼠的减肥降脂试验表明，文冠果叶总皂苷对胰脂肪酶的抑制活力最高可达68.29%，且在高血脂模型中，高、中、低剂量文冠果叶总皂苷均可显著或极显著降低血清中的TC、TG、LDL-C浓度，提高HDL-C浓度，其中高剂量组的降脂作用与阳性对照药物奥利司他效果相当。【结论】文冠果叶总皂苷减肥降脂功效显著，能够有效抑制胰脂肪酶活力，降低胆固醇和甘油三酯含量，进而促进脂肪代谢。     

Effect of allele combinations at Ppd-1 loci on durum wheat grain filling at contrasting latitudes

Flowering time is the most critical developmental stage in wheat, as it determines environmental conditions during grain filling. Thirty-five spring durum genotypes carrying all known allele variants at Ppd-1 loci were evaluated in fully irrigated field experiments for three years at latitudes of 41°N (Spain), 27°N (northern Mexico) and 19°N (southern Mexico). Relationships between weight of central grains of main spikes (W) and thermal time from flowering to maturity were described by a logistic equation. Differences in flowering time between the allele combination causing the earliest (GS100/Ppd-B1a) and the latest (Ppd-A1b/Ppd-B1a) flowering were 7, 20 and 18 days in Spain, northern Mexico and southern Mexico, respectively. Flowering delay drastically reduced the mean grain filling rate (R) and W at all sites. At autumn-sowing sites, an increase of 1°C in mean temperature during the first half of the grain filling period decreased W by 5.2 mg per grain. At these sites, W was strongly dependent on R. At the spring-sowing site (southern Mexico), W depended on both R and grain filling duration. Our results suggest that incorporating the allele combinations GS100/Ppd-B1a and GS105/Ppd-B1a (alleles conferring photoperiod insensitivity) in newly released varieties can reduce the negative effects of climate change on grain filling at the studied latitudes.     

河南卫河流域脆弱性评价

结合卫河自身特点和地理环境建立13项指标体系,运用基于熵权的模糊数学模型对其脆弱性进行评价。结果表明,鹤壁的脆弱性为0.69,焦作为0.55,新乡为0.39,安阳为0.36,濮阳为0.23。最后针对评价结果分析了原因,提出了合理性建议和措施。     

基于案例推理的产品质量安全风险评估研究

为了建立健全产品质量安全风险管理体系，加强产品质量安全风险预警的要求，同时最大程度地利用过去成功的风险评估案例，构建了基于案例推理的产品质量安全风险评估系统。针对某种产品，根据专家的知识建立风险评估指标体系，并将每个评估指标赋权重，计算与案例库中的各个案例相似度，寻找出最大相似度案例，据此，辅助相关人员对目标案例进行风险分析与评估。     

Survey and new insights in the application of PCR‐based molecular markers for identification of HMW‐GS at the Glu‐B1 locus in durum and bread wheat

Wheat, among all cereal grains, possesses unique characteristics conferred by gluten; in particular, high molecular weight glutenin subunits (HMW‐GS) are of considerable interest as they strictly relate to bread‐making quality and contribute to strengthening and stabilizing dough. Thus, the identification of allelic composition, in particular at the Glu‐B1 locus, is very important to wheat quality improvement. Several PCR‐based molecular markers to tag‐specific HMW glutenin genes encoding Bx and By subunits have been developed in recent years. This study provides a survey of the molecular markers developed for the HMW‐GS at the Glu‐B1 locus. In addition, a selection of molecular markers was tested on 31 durum and bread wheat cultivars containing the By8, By16, By9, Bx17, Bx6, Bx14 and Bx17 Glu‐B1 alleles, and a new assignation was defined for the ZSBy9_aF1/R3 molecular marker that was specific for the By20 allele. We believe the results constitute a practical guide for results that might be achieved by these molecular markers on populations and cultivars with high variability at the Glu‐B1 locus.     

基于相对熵排序的建筑工程项目投标决策

投标决策是施工企业面对的重要问题．在建筑工程项目投标问题上，先建立风险指标体系，再结合层次分析法和信息熵法求得风险指标的综合权重，然后借助相对熵排序法，对各个方案进行综合评价，得到有效反映各方案差异的评价模型，通过对比可知此法可行有效，且灵敏度高．     

铜仁烤烟单叶重现状与提升烟叶质量对策

根据铜仁烤烟单叶重的调查数据，认真梳理了铜仁烤烟单叶重的现状，分析了铜仁烤烟单叶重存在的问题，从烟叶收购政策和烟叶生产技术两个方面有针对性的提出提升铜仁烟叶质量的对策，为铜仁烤烟产业的持续健康发展提供理论指导。     

茶树小分子量热激蛋白基因CsHSP17.2的克隆与表达分析

[目的]进一步了解茶树小分子量热激蛋白基因CsHSP17.2在逆境胁迫条件下的分子生物学功能.[方法]利用RT-PCR技术从茶树‘迎霜’中克隆得到CsHSP1 7.2基因,运用生物信息学软件分析其核苷酸和编码蛋白,通过Real-timePCR分析其表达模式.[结果]该基因开放阅读框长度为453 bp,编码150个氨基酸,蛋白质相对分子质量为17.2×10a,理论等电点5.56;无信号肽位点,属于非分泌型蛋白;被定位于细胞质中.系统发育树分析表明,茶树CsHSP1 7.2与水稻(GenBank登录号:P27777)和花生(ABC41131)的进化关系较近,属于小分子量热激蛋白基因家族第Ⅰ亚族.qRT-PCR分析发现,茶树CsHSP17.2属于组成型基因;高温(38℃)处理1h能显著提高CsHSP17.2 mRNA的相对表达量(P＜0.05);干旱(100 g·L-1 PEG 6000)、高盐(200 mmol· L-1 NaCl)和外源脱落酸(200 mg· L-1 ABA)处理条件下,该基因的转录水平均出现不同程度的上调.[结论]克隆得到茶树‘迎霜’小分子量热激蛋白基因CsHSP17.2,其在花中表达量最高,且响应高温、干旱、高盐和外源脱落酸胁迫.     

新疆春小麦育成品种耐热性评价

为筛选出耐热性好的小麦种质材料，通过开花期至成熟期人工模拟高温胁迫环境，以千粒重热感指数为主要评价指标，评价了新疆近30年来审定的春小麦品种的相对耐热性，并分析了高温胁迫对小麦籽粒蛋白质、湿面筋含量的影响。结果表明，与自然生长相比，高温胁迫条件下新疆春小麦育成品种的千粒重、籽粒宽度的变化均达到了极显著水平（P<0.01），籽粒长度变化不显著(P>0.05)，不同品种间耐热性存在很大差异。综合三年千粒重热感指数（HSI）分析，耐热性相对较好的品种有17个，连续三年HSI＜1的品种有11个，其中新春37号、新春2号、新春38号在高温胁迫条下千粒重变化较小，产量较稳定，为强耐热品种；对高温敏感品种有26个，连续三年HSI≥1的品种有13个，其中新春13号、新春18号、新春33号耐热性相对较弱。高温胁迫影响小麦籽粒的品质，其中13.95%的品种蛋白质含量降低，6.98%的品种湿面筋含量降低，其他品种高温胁迫后籽粒蛋白质、湿面筋含量均较自然生长有所提高。