测定豆腐产量微量方法的研究

本文的豆腐产量微量测定方法是在单株或单粒的基础上测定豆腐产量，试验处理的样品用量分别为１粒，２粒，４粒，６粒，８粒和１０粒种子，用以制务和测定干，湿豆腐产量，以常规方法作为对照。     

低盐锻炼提高水稻幼苗耐盐性及其与活性氧毒害的关系

 研究了幼苗期低盐锻炼对水稻耐盐能力的影响。中国91和83-51幼苗经低盐(0.1% NaCl)锻炼后可降低盐处理(0.3% NaCl)对其生长的抑制; 低盐刺激叶片超氧化物歧化酶和过氧化氢酶活性升高,从而在盐胁迫时保持较高活性;虽然低盐也使过氧化物酶活性、丙二醛含量以及Na+含量有一定程度的增加,但在盐胁迫时其增加速率明显减慢而低于未经低盐锻炼的苗株；相反，低盐锻炼时K+含量有所下降，但在盐胁迫时其下降幅度低于未经低盐锻炼的植株，至处理结束,两者水平接近。结果表明,幼苗期采用低盐锻炼的方法可以增强水稻的耐盐能力, 这与低盐锻炼可在一定程度上增强地上部组织内清除活性氧的防护系统能力, 使其在随后的盐胁迫过程中由活性氧诱导脂质过氧化作用产生的盐渍伤害减轻有关     

内蒙古汗马国家级自然保护区冬季有蹄类种群数量调查

[目的]明确内蒙古汗马国家级自然保护区冬季有蹄类种群数量,完善保护区内动物分布种类与种群数据。[方法]2012年12月末至2013年1月,应用大样方法对内蒙古汗马国家级自然保护区冬季有蹄类动物种群数量进行调查。[结果]共记录到有蹄类动物3种,隶属于1目2科。其中原麝(Moschus moschiferus sibiricus)属于国家I级保护动物,驼鹿(Alces alces)属于国家II级保护动物,狍(Capreolus pygargus)属于国家"三有"动物。保护区内分布的驼鹿种群数量为242(93~504)只;狍的种群数量为485(167~759)只。由于原麝仅在1个样方内出现,所以无法对其种群数量进行合理评估。[结论]研究结果为内蒙古汗马国家级自然保护区动物保护提供了参考。     

农药的绿色分析方法研究Ⅰ.聚乙二醇辛基苯基醚水溶液作为农药前处理试剂的研究

为了避免检测农药残留试样前处理过程中有毒有机溶剂的使用，用聚乙二醇辛基苯基醚（OP）水溶液作为提取蔬菜样品中甲氰菊酯、功夫菊酯和氯氰菊酯农药残留物的萃取剂，采用固相萃取方法（SPE）对萃取液中农药进行富集。通过改变OP水溶液浓度和有机添加剂种类，研究了萃取和富集的条件：以5％OP＋2％尿素作提取液，过SPE小柱，乙腈洗脱。所研究的样品前处理方法用于蔬菜样品中几种菊酯类农药的检测，与液液萃取方法相比，本试验结果相对偏差为2．7％～7．7％。     

A combined model of dissolved oxygen prediction in the pond based on multiple-factor analysis and multi-scale feature extraction

As dissolved oxygen (DO) is an important indicator of water quality in aquaculture, an accurate prediction for DO can effectively improve quantity and quality of product. Accordingly, a novel hybrid dissolved oxygen prediction model, which combines the multiple-factor analysis and the multi-scale feature extraction, is proposed. Firstly, considering that dissolved oxygen is affected by complex factors, water temperature and pH are chosen as the most relevant environmental factors for dissolved oxygen, using grey relational degree method. Secondly, the ensemble empirical mode decomposition (EEMD) is adopted to decompose the dissolved oxygen, water temperature and pH data into several sub-sequences, respectively. Then, the sample entropy (SE) algorithm reconstructs the sub-sequences to obtain the trend component, random component and detail component. Lastly, regularized extreme learning machine (RELM), a currently effective and stable artificial intelligent (AI) tool, is applied to predict three components independently. The prediction models of random component, detail component and trend component are RELM1, RELM2 and RELM3 respectively. The dissolved oxygen, water temperature and pH of the random component forms the input layer of RELM1, and predicted value of dissolved oxygen in the random component is the output layer of RELM1. The input and output of RELM2 and RELM3 are similar to that of RELM1. Final prediction results are obtained by superimposing three components predicted values. One of the main features of the proposed approach is that it integrates the multiple-factor analysis and the multi-scale feature extraction using grey correlation analysis and EEMD. Its performance is compared with several outstanding algorithms. Results for experiment show that the proposed model has satisfactory performance and high precision.     

γ能谱分析中不同形状体源的探测效率研究

利用天然铀粉末和铀镭平衡粉末分别制作了用4种模拟土壤基质体源,并封装在4种不同几何形状的样品杯中,通过HPGeγ谱仪分析比较了63～1847keV能量范围内不同几何形状体源的效率,分析了效率差异的原因,并对在实际样品测量中选取合适样品杯提出了建议。     

基于SCoT标记分析紫花苜蓿遗传多样性的取样数量

本研究采用目标起始密码子多态性(Start codon targeted,SCoT)标记,对600份不同紫花苜蓿(Medicago sativa L.)材料(共6个种质)的基因组DNA进行扩增,分析了不同取样数量下(10,15,20,30,40,50,60,70,80,90和100)紫花苜蓿的遗传多样性,旨在筛选出代表紫花苜蓿种群遗传多样性的最佳取样单株数。结果发现,6条SCoT引物共扩增出80个条带,平均每条引物的扩增条带数为13.3个,多态性条带百分率为100%。在评价不同取样梯度下的紫花苜蓿遗传多样性覆盖度时发现,当取样数量增加至40时,6个供试紫花苜蓿种质的遗传多样性覆盖率均达到95%以上。此外,本试验采用UPGMA与STRUCTURE聚类分析方法,分析了不同取样梯度下紫花苜蓿的遗传结构。结果表明,样本量为40时能够有效反映紫花苜蓿群体间差异。     

小麦幼胚培养研究进展

以幼胚为外植体进行小麦组织培养的方法越来越受到人们的重视.为了了解小麦幼胚培齐研究进展,针对我国小麦幼胚组织培养研究现状,着重综述了小麦胚龄、培养基、生长调节物质、预处理等对小麦幼胚离体培养的影响.     

A practical approach to calculate sample size for herd prevalence surveys

When designing a herd-level prevalence study that will use an imperfect diagnostic test, it is necessary to consider the test sensitivity and specificity. A new approach was developed to take into account the imperfections of the test. We present an adapted formula that, when combined with an existing piece of software, allows improved planning. Bovine paratuberculosis is included as an example infection because it originally stimulated the work. Examples are provided of the trade-off between the benefit (low number of herds) and the disadvantage (large number of animals per herd and exclusion of small herds) that are associated with achieving high herd-level sensitivity and specificity. We demonstrate the bias in the estimate of prevalence and the underestimate of the confidence range that would arise if we did not account for test sensitivity and specificity.