基于数字图像分析法的片烟干燥收缩特性研究

为提升烟叶打叶复烤加工质量、降低复烤过程片烟收缩,以烤烟上部橘黄二级烟叶(B2F)和中部橘黄二级烟叶(C2F)打后片烟为材料,采用机器视觉装置并结合数字图像分析法,对片烟收缩特性进行检测和表征,对干燥过程片烟收缩特性进行分析,并探讨了烟叶原料部位、打后尺寸对片烟干燥收缩特性的影响.结果表明,图像分析法用于片烟收缩特性测试具有较好的精确性,一定条件下片烟收缩率测试结果的相对标准偏差低于6％.干燥过程中片烟收缩形变主要来源于干燥前期的快速脱水阶段,随着干燥过程含水率的降低,片烟收缩率变化趋缓.C2F的收缩率明显高于B2F,实际复烤干燥加工热风温湿度和终点水分下,C2F、B2F收缩率分别达14.3％、11.9％.不同尺寸片烟收缩特性存在差异,B2F片烟收缩率随尺寸增加而明显增大.可见,对于不同等级部位烟叶原料,通过复烤前片烟打叶尺寸的调节和复烤过程适当降低脱水速率,可有效控制收缩形变.     

Determination of equine deep digital flexor muscle volume based on distances between anatomical landmarks

In equine medicine the use of Botox® is experimental. Dosages are determined from human treatment-protocols and limited numbers of equine studies. Determination of target-muscle volume can be helpful to extrapolate human dosages. The aim of the study was to calculate a formula enabling the estimation of the deep digital flexor muscle (DDFM) volume based on distances between anatomical landmarks.     

Comparison of Insulin-Induced Digital Vessel Ring Responses of Laminitic and Clinically Healthy Horses

Hyperinsulinemia leads to insulin resistance of blood vessels and interferes with circulation of laminae of the equine foot. The objective of the study was to compare the digital vessel responses of clinically healthy and laminitic horses with and without experimental induction of insulin resistance. Vessel segments (artery and vein) collected after euthanasia were cut into 3-mm wide rings and were prepared in tissue baths containing Tyrode solution for response studies. Two rings of each vessel type from each horse were used as nonresistant, and two were made insulin resistant. Insulin resistance was induced by incubating the rings with 10-μM bath concentration of insulin. Then, all rings were contracted with phenylephrine (5 μM). When the contraction reached a plateau, insulin (10 μM) was added, and the response monitored for 30 minutes. The response to insulin was calculated as a percentage of the phenylephrine response. The results showed that the responses of the nonresistant rings differed significantly between the groups. However, when all rings were made insulin resistant, the significance between the groups disappeared. In the laminitic group, responses of resistant and nonresistant rings did not differ, whereas in the healthy group, the vessel responses differed significantly. In all experiments, arterial and venous rings followed the same pattern, but the magnitudes were greater in arterial rings. The findings suggest that the vessel responses to insulin are altered in laminitis which could be due to insulin resistance.     

Participatory Rural Appraisal and Compensation Intervention: Challenges and Protocols While Managing Large Carnivore–Human Conflict

When large carnivores cause socioeconomic losses in a community, conflict increases, retaliatory killing of the carnivore can occur, and conservation efforts are undermined. We focused on Participatory Rural Appraisal (PRA) and economic compensation schemes as approaches for managing conflict. PRA is a tool for collecting data on the large carnivore–human conflict and economic compensation schemes for those affected negatively by carnivore presence. We reviewed published papers and reports on large carnivore–human conflicts, PRA, and compensation schemes. This article details insights into common pitfalls, key lessons learned, possible solutions including new approaches for compensation and protocols to be followed while managing large carnivore–human conflict. We hope to contribute to a meaningful dialogue between locals, managers, and researchers and help in effective implementation of conservation programs to mitigate large carnivore–human conflict around the protected areas.     

连续型光谱数据的处理及信息提取试验

应用切比雪夫多项式和傅立叶级数,对连续型光谱数据进行了数据压缩和信息提取的试验,证明切比雪夫多项式和傅立叶级数均能有效地压缩光谱数据和提取光谱信息。     

从我校博士生吸收国外文献的能力看我馆外刊馆藏建设

外文期刊是高等学校科研与教学重要的文献资源，外文期刊的利用率和对科研教学满足率是衡量外文藏刊建设质量的重要指标。本文通过对中国农业大学有代表性的部分专业博士学位论文的引文分析，对馆藏外文期刊的满足和利用情况进行了分析，认为我馆外文期刊的利用率和满足率是比较高的，对外文期刊的馆藏建设提供了一些建设性建议。     

数字图书馆实现电子商务模式

随着电子商务借助Intemet平台的兴起与发展，对数字图书馆也产生了深远影响。本文阐明了数字图书馆实现电子商务方式的现实环境，并介绍了数字图书馆实现电子商务模式。     

中国蜡梅种质资源核心种质的初步构建

该文对中国蜡梅野生资源和品种资源分别构建了核心种质。并按居群进行分组,共分为2大组13个小组。各组内在9个表型性状聚类的基础上,按平方根法取样,并依遗传多样性指数和遗传丰富度进行调整,构建了中国蜡梅种质资源的163份初选核心种质,其中野生初选核心种质77份,占总数的26·9%,几乎覆盖了蜡梅的全部分布区,品种初选核心种质86份,占总数的50·6%。根据对9个性状遗传多样性指数的t检验和观赏性状特征值检验,结果表明,初选种质较好地代表了全部供试种质的遗传变异幅度。     

数字地面模型的建立及应用

数字地面模型为多种地形特征的定量分析与地形图的自动化绘制提供了基本数据，它是建立土建ＣＡＤ和地理信息系统的基础。随着计算机的发展与普及，它越来越受到测绘工作前和工程设计人员的重视。本文简要介绍了数字地面模型的建立过程。文中提出利用公里格网进行坐标转换不仅方便而且可靠；对移动拟合法建立数字地面模型时的定权及采样点密度进行了讨论；对采用三次样条插值方法绘制等值线进行了实验。     

非惯性系中弹性薄板的全局分叉和混沌性质

首先对非惯性参考系中弹性薄板动力学行为进行了奇点分析，进而求出了奇点附近同宿轨与周期轨的参数方程，用Ｍｅｌｎｉｋｏｖ方法研究了同宿轨分叉与周期轨的次谐分叉和混沌，对于各种不同的其振情况，系统将经过无限次奇阶次数谐分叉产生Ｓｍａｌｅ马蹄进入混沌状态，最后利用数值仿真研究了该系统的混沌运动。