Mating behaviour and maternal care in the tropical savanna funnel-web spider Aglaoctenus lagotis Holmberg (Araneae: Lycosidae)

Despite their abundance and diversity, Neotropical spiders have been the subject of relatively few studies of behavioural ecology. The sexual behaviour and maternal care of the spider Aglaoctenus lagotis (Lycosidae) is described here. We performed experimental manipulations to test the hypothesis that males are attracted by female cues in the web. Two predictions were tested: (a) webs used by a virgin female will attract more males than webs used by an inseminated female; (b) the main cue in the web is chemical, so webs recently used by virgin females will attract more males than those that are not recently used. Additionally, we tested the hypothesis that maternal care increases offspring survivorship. Results showed that males are attracted by recently used webs (z = 0.0015; p = 0.037; z-test) and webs of virgin females (z = 0.041; p = 0.036, z-test). Male sexual behaviour presented three different categories: court, pre-mate and mate. After the mating, the females built a cocoon that was transported adhered to the spinnerets and held by the last pair of legs. After the hatching of the eggs, the young migrated to the dorsal region of the mother's body for 5 days. During maternal care the mother eliminates a yellowish drop from its oral cavity, which is collected by the young. During the development of the young until adulthood, the offspring that have their mother present in the first stages of life have greater survival compared with those without maternal care. Our results make it possible to perform comparative analyses between a South American Lycosidae species and other species distributed worldwide.     

食品双螺杆挤出机温控系统的模糊免疫PID控制

食品双螺杆挤出机机筒温度对挤压产品产量和质量影响很大,实现对机筒温度的有效控制是一项重要工作.建立控制对象的数学模型,借鉴生物体免疫机理,设计出模糊免疫PID控制器,并进行了仿真研究.结果表明,该温控系统鲁棒性强,响应速度快,动态误差小,性能优于单一的PID控制,能满足食品加工工艺的要求.     

二次微分电位溶出法测定食品中镉、锌含量

建立了二次微分电位溶出法测定食品中镉、锌含量的方法.优化了试验条件如pH值、电沉积电位、平衡电位等,线性范围:镉0～16 ng,锌0～800 ng;检出限分别为0.24 ng/mL、0.71 ng/mL,RSD<2.5%(n=7).该法测定食品样品结果与石墨炉原子吸收法一致.     

可持续发展的食品体系及绿色消费体系构建研究

构建可持续发展的区域食品体系,是促进我国可持续发展的现实选择。它不仅能促进区域经济繁荣和区域自然资源的保持,缩短食品流通距离,降低流通成本,而且还可以创造更多的就业机会来提高农民的收益。建立可持续发展的区域食品体系,关键在于持续生产模式、健康消费模式和食品安全保证体系及绿色销售渠道的构建。     

一类食物链模型的周期解

讨论了一类复杂食物链模型的全局性质,应用Gaines-Mawhin's叠合度理论,得到了该类食物链模型正周期解全局存在的充分条件.     

PDCA循环在食品化学与理化检验课程教学环节中的应用

文章将PDCA循环法引入食品化学与理化检验教学环节中,从可行性、具体运用以及教学中运用PDCA循环的优势几方面论述,以期有效提高高校食品化学与理化检验教学质量,培养更多高素质食品人才。     

高钙食品中痕量铅的极谱测定

建立了在0.6%碘化钾-0.8%酒石酸钾钠-0.36 mol/L盐酸-0.14 mol/L磷酸-0.6%三乙醇胺-0.1%抗坏血酸底液条件下,用单扫描极谱法测定高钙食品中痕量铅的方法.试验表明,本法的线性范围为5～800 ng/mL,检出限为1.5 ng/mL,样品加标回收率为95%～107%,相对标准偏差为4.3%～8.5%.     

电位溶出分析法同时测定罐头食品中痕量铅锡

利用不除氧电位溶出分析法成功地测定了溶出电位相近的Ｐｂ、Ｓｎ两元素。以０．０５ｍｏｌ／Ｌ草酸为介质，调节溶液ＰＨ＝１．０，以溶解氧做氧化剂，静止溶出，两元素均有分高清晰的平台出现。Ｐｂ、Ｓｎ的线性范围分别为：２．０×１０－９～２．０×１０－７ｍｏｌ／Ｌ和２．０×１０－８～２．０×１０－６ｍｏｌ／Ｌ。当富集时间为４ｍｉｎ时，Ｐｂ、Ｓｎ的检测限分别为５．０×１０－１０ｍｏｌ／Ｌ和５．０×１０－９ｍｏｌ／Ｌ。此法已成功地应用于测定罐头食品中的痕量Ｐｂ、Ｓｎ。     

开发食疗宝库,发展中国特色的功能食品

功能食品是当代食品研究和开发的世界性潮流，它被称之为２１世纪的食品，这类食品不仅具有一般食品具备的营养和感官功能，还具一般食品所没有的调节人体生理的功能，该文论述了功能食品的定义，特征，产生的历史背景及存在的问题，也提出了功能性食品今后的发展方向。     

几种腌薰食品中亚硝酸盐及其含量的调查分析

本文报导了吉首市5种传统腌熏食品中亚硝酸盐含量的调查结果。结果表明，这类食品中都含有亚硝酸盐。其亚硝酸盐含量的均值（24.5mg/kg）高于其鲜类食品。通过比较分析，亚硝酸盐的形成及含量与腌熏类食品的制作技术及环境有关。