果蔬冷链物流保鲜市场现状及发展趋势

冷链物流保鲜在果蔬产业中占有重要地位。在物流链中,大部分果蔬易因贮藏条件不当而变质,造成大量浪费。从整个冷链物流保鲜产业中存在的问题出发,探究果蔬物流保鲜市场现状,探讨未来果蔬产业物流保鲜的趋势以及应用价值。     

基于供应链的乳品质量安全影响因素研究

乳品的质量安全是制约乳品行业健康发展的重要因素,从乳品供应链上原奶的供应、原奶的收购和乳制品的加工、乳品的流通和销售、消费者食用四个环节出发,分析了影响乳品质量安全的因素,并提出了控制和协调乳品供应链中原奶供应、乳品生产、以政府的主体行为来保障乳品的质量和安全的对策。     

汽车发动机正时链系统行走轨迹计算与试验

在已知汽车发动机配气正时机构三轴坐标的基础上,研究了正时链系统几何布局设计及其行走轨迹、约束边界的设计计算方法,依据曲线的内凹量,采用分段圆弧或直线逼近的方式,提出了张紧边和导向边的长度计算准则。通过发动机缸盖反拖系统试验台,在真实模拟正时链系统交变载荷和工作环境的条件下,研究了张紧板在不同转速条件下的横向振动位移的变化规律,以及不同转速条件下的噪声特性变化规律。分析结果表明,所提出的正时链系统行走轨迹计算方法,在保持该系统的适度张紧的前提下,正时链整链磨损伸长与张紧器柱塞探出量之间具有较好的谐应关系,同时,正时链系统在发动机常用转速工况下,张紧边的横向位移波动情况及噪声特性能够满足汽车发动机的动力性能要求。     

活化卵白蛋白对断奶仔猪结肠内SCFA的影响

为了研究活化卵白蛋白对断奶仔猪结肠内短链脂肪酸(short chain fatty acid,SCFA)的影响,选取54头20日龄健康仔猪,随机分为3个处理组。23日龄开始,Ⅰ组饲喂基础日粮+活化卵白蛋白10 mL·d-1·头-1,Ⅱ组饲喂基础日粮+啤酒酵母10 mL·d-1·头-1,Ⅲ组连续饲喂基础日粮10 d,28日龄断奶。仔猪在23,28,35,42日龄时,从每个重复中随机选1头屠宰,迅速结扎结肠两端,无菌收集结肠食糜,利用气相色谱法测定结肠内SCFA含量。试验结果表明: (1)仔猪28日龄时,与Ⅲ组相比,Ⅰ组仔猪结肠内乙酸(P＜001)、丙酸(P＜005)、丁酸(P＜005)和总SCFA(P＜001)含量升高,而异丁酸(P＜001)含量降低;与Ⅱ组相比,Ⅰ组仔猪结肠内乙酸(P＜001)、异丁酸(P＜001)和总SCFA(P＜001)含量升高;(2)仔猪42日龄时,与Ⅱ组、Ⅲ组相比,Ⅰ组仔猪结肠内乙酸、丙酸、丁酸、异戊酸和总SCFA含量显著升高(P＜005);(3)随着仔猪日龄的增加,各组仔猪结肠内总SCFA含量均增加,但Ⅰ组增加最明显。由此看来,活化卵白蛋白可以提高断奶仔猪结肠内SCFA含量。     

区别鹅细小病毒和番鸭细小病毒的PCR-RFLP方法的建立

根据GenBank登录的鹅细小病毒（GPV）和番鸭细小病毒（MDPV）非结构蛋白（NS）基因特征,本研究设计1对特异性引物对GPV和MDPV基因组DNA进行PCR扩增,目的片段大小均为810 bp,并对PCR产物进行切胶回收。用EcoRⅠ酶对GPV和MDPV特异性胶回收产物进行酶切鉴定,结果显示MDPV经EcoRⅠ酶切后琼脂糖凝胶电泳检测片段为2段,大小为530和280 bp;而GPV经EcoRⅠ酶切后琼脂糖凝胶电泳检测片段大小不变。本研究建立了一种快速区别GPV和MDPV感染的检测方法,可对番鸭感染水禽细小病毒的情况进行快速鉴别诊断。     

Systematic position of copepods of the genus Achtheres (Crustacea: Copepoda: Siphonostomatoida) parasitizing perch, Perca fluviatilis L., and zander, Sander lucioperca (L.)

Parasitic copepods of the genus Achtheres commonly infect perch, Perca fluviatilis, and zander, Sander lucioperca, in Europe. The aim of this study was to verify the specific identity of these copepods. The parasites were examined morphologically, biometrically and genetically. Statistical processing of the biometrical data was based on both empirical measurements and transformed data related to total length and genital trunk width. Principal component analysis was applied to both sets of data. DNA of both parasite 'forms' was amplified using two sets of primers (EU5.8S+EU18S and 18SF1+28SR) and the products were subjected to restriction fragment length polymorphism (RFLP). Morphological differences were found in the overall shape of the copepod bodies as well as in the details of the armament of some appendages. The morphometric study emphasized the importance of second maxillae and genital process as the variables most distinctly distinguishing the two 'forms'. The two 'forms' of Achtheres differed in the DNA sequence amplified by one set of primers. RFLP revealed even more extensive differences between these two copepods. We concluded that the copepods parasitizing perch should be referred to as Achtheres percarum von Nordmann, 1832, whereas a long-forgotten name, A. sandrae Gadd, 1901, should be applied to the copepods from zander.     

顾客价值视角下的林业企业价值链管理

通过建立顾客价值层次结构模型,运用改进的模糊层次分析法,确定林业企业价值链各作业活动的顾客价值贡献度,对林业企业核心竞争力加以识别;依据二维决策支持矩阵,对林业企业的业务流程重组、外包业务等战略问题提供决策支持。     

基于模糊层次分析法的供应商选择

在全面分析和借鉴国内外供应商评价的有关理论和方法成果的基础上,构建基于合作环境下的供应商选择与评价指标体系,从质量、生产能力、技术能力、企业绩效、合作与兼容性五个方面对供应商进行评价,并在模糊层次分析法的基础上结合案例对供应商的选择进行实证分析探讨。     

A decision support approach for cane supply management within a sugar mill area

Increased competition between agri-food supply chains has strained relationships between farmers and processing factories while reducing individual profit margins. Decisions at different levels of the supply chain can no longer be considered independently, since they may influence profitability throughout the supply chain. This paper presents a decision support approach based on the MAGI^® simulation tool, which aims to facilitate discussion and negotiation between stakeholders while collectively exploring satisfactory solutions.The simulation tool helps sugarcane growers and millers in designing and assessing new ways of organizing cane supply management within a mill area. It addresses key issues such as restructuring mill areas or changing cane delivery allocation rules in order to increase total sugar production and total net revenue at the mill area level. This approach has been implemented for two mills in Réunion and one mill in South Africa. Simulations showed that sugar gains may be obtained by rearranging supply scheduling according to quality-based zoning within a mill area. Discussions led to further studies regarding the practicality of the best scenarios. MAGI^® is now available as freeware for testing in different settings.     

信号肽对鸡Igλ轻链绿色荧光蛋白重组分子在COS7细胞上分泌表达的影响

分别将鸡Igλ轻链信号肽、小鼠纤溶酶原信号肽与pEGFP-C1载体的绿色荧光蛋白N端融合,产生带有信号肽的中间载体pEGFP-SPc和pEGFP-SPm。对鸡Igλ轻链基因的定向克隆,构建了带有纯化标签的鸡Igλ轻链绿色荧光蛋白真核表达载体pEGFP-SPc-λ和pEGFP-SPm-λ。转染COS7细胞后,荧光显微镜观察及Western blotting检测融合蛋白的分泌表达,结果显示,鸡Igλ轻链信号肽能引导鸡Igλ轻链绿色荧光蛋白融合分子的分泌表达;而小鼠纤溶酶原信号肽不具备引导该重组蛋白分泌表达的功能。表明信号肽在蛋白分泌表达中的关键作用,重组蛋白的分泌表达要选择合适的信号肽。