普洱茶茶褐素的制备工艺、组成结构与生理功效研究进展

茶褐素是能溶于水而不溶于氯仿、乙酸乙酯、正丁醇和乙醇的一类褐色色素，由茶黄素和茶红素进一步氧化聚合而成，具有较强的降血脂、降血糖、抗氧化等药理活性。综述了茶褐素的制备工艺、组成结构和功能活性，以表格的形式清晰的展示出不同制备工艺所得茶褐素的组成结构的区别；在结尾部分分析目前茶褐素研究面对的困难，并进行了展望。     

环境异质性对红砂叶片功能性状的影响

为探究红砂(Reaumuria soongorica)生态适应过程中环境和遗传变异之间的相对关系，本研究采用野外调查及同质园栽培试验的方法，测定红砂叶片形态和化学计量指标，分析比较了野外和同质园叶片功能性状的差异。结果表明：同一种源同质园红砂叶组织密度、肉质化程度、含水量均低于野外，且同质园红砂叶组织密度、肉质化程度、含水量在不同种源地与野外表现出相似的变化趋势，比叶面积表现为相反的变化趋势。野外种源红砂生长受氮和磷共同限制，而同质园红砂只受氮限制，红砂叶片含水量与肉质化程度、组织密度与比叶面积、氮含量与比叶面积、氮含量与N/P在同质园与野外相关性表现一致，但同质园碳、氮、磷与其它性状之间的相关性与野外不同，且微量元素钠、镁、铁、锌含量在野外与同质园间具有显著性差异。综上所述，红砂叶组织密度、肉质化程度、含水量及部分性状间权衡关系受遗传影响较高，在环境改变时也存在适应性分化，遗传因素对红砂叶化学计量特征影响较小，且环境变化会导致红砂对氮和磷元素利用方式发生改变。     

干果强化牦牛酸奶的功能性及研究进展

牦牛乳营养价值丰富,其脂肪(5.5%~7.5%)、蛋白质(4.0%~5.9%)和乳糖(4.0%~5.9%)含量均高于普通牛乳,其含脂率较高、风味独特、品质优良,是生产加工保健功能产品的优质原料。同时,干果作为一种天然的生物活性成分,富含不饱和脂肪酸、优质植物蛋白、纤维、矿物质、生育酚、植物甾醇和酚类化合物等生物活性化合物,可为人体健康提供诸多重要营养物质,还是一种不被消化的碳水化合物的益生元来源,适合作为强化剂添加到酸奶中,强化理化性质和营养品质,制备功能性酸奶。本文论述了干果作为强化剂添加到牦牛酸奶中制备功能性酸奶的益处,包括改善理化性质、丰富酸奶的生物活性成分及增添膳食纤维和蛋白质等益生元成分。同时指出了当前功能性酸奶研发及消费市场中存在的一些问题,如:功能性酸奶强化剂的应用短缺、国民对功能性酸奶的消费意识薄弱和企业规模小、设备制造技术落后等,旨在为开拓功能性酸奶市场提供助力,为国民体质的改善和健康水平的提高发挥作用。     

Multifunctionality in practice: Measuring differences in urban woodland ecosystem properties via functional traits

The ability of urban woodlands to regenerate and provide ecosystem services depends on the maintenance of a range of ecosystem functions and processes (i.e. multifunctionality). Many conservation decisions are made by local land stewards and rely on taxonomic characterization of woodlands to infer ecosystem properties, but there is reason to doubt this approach. Can functional traits provide better information on ecosystem multifunctionality? We compare three methods for capturing differences in urban woodland multifunctionality. We ask whether differences in (1) species composition, (2) traits associated with urbanization (urbanization markers) or (3) traits associated with specific ecosystem properties (functional markers) best capture actual differences in colonisation, water infiltration and decomposition in woodlands across a rural-urban gradient (Montreal, Canada). We use Procrustes superimposition and Mantel tests to compare the fit of each method. We propose the functional Mahalanobis distance to measure the distance of an urban woodland from a reference range of multifunctionality.All three methods were significantly congruent with actual differences in ecosystem multifunctionality, but the strength of the rank-order correlations varied widely. Species composition and urbanization markers had a similar but weak correlation with differences in multifunctionality. Importantly, the mismatch between species composition and multifunctionality increased with urbanization. Functional markers captured ecosystem multifunctionality better than either species composition or urbanization markers.Commonly used species- and general trait-based approaches were poor measures for multifunctionality in our urban woodlands. Functional markers rely on vegetation inventories already routinely collected by land stewards and openly available trait information: they may provide a cost-effective way of capturing multifunctionality in urban systems. More broadly, the functional Mahalanobis distance provides a quantitative measure of site-level multifunctionality that allows land stewards to compare woodlands with a reference range of variability in a format that can directly inform conservation decisions.     

放牧强度对半干旱草地优势植物赖草功能性状的影响

放牧是草原生态系统中草地利用的主要方式，研究草地植物功能性状对长期放牧干扰的响应策略具有重要意义。本文以晋北农牧交错带半干旱草地为例，研究优势植物赖草(Leymus secalinus)功能性状在不同放牧强度下的变化，结果表明：放牧显著降低了赖草株高等形态结构性状以及茎叶比等生产力性状(P<0.05)，中度放牧与不放牧的差异最小；整株干重(地上部分)的变异系数(52.92%)和可塑性指数(93.17%)最大；生产力性状、光合生理性状和化学计量3类性状内部指标之间的相关性均为极显著正相关(P<0.01)；茎氮磷比等性状是赖草响应放牧干扰的主要功能性状。本研究表明，中度放牧下，赖草具有补偿性生长的能力，矮化型变特征和非对称性响应机制是赖草在放牧干扰下的主要适应方式。     

Effect of non-conventional modified atmosphere packaging on fresh cut watercress (Nasturtium officinale R. Br.) quality

In recent years, the minimally processed food industry has increased due to a consumer trend toward healthier eating. Among these products, watercress represents an interesting alternative due to its high content of functional compounds. The aim of this study was to investigate the effect of non-conventional modified atmosphere packaging (nitrogen (89.7% N₂, 10.3% O₂), argon (89.9% Ar, 10.1% O₂), helium (90.1% He, 9.9% O₂), nitric dioxide (89.3% N₂O, 10.7% O₂) and air (0.03% CO₂, 21% O₂)) on fresh-cut watercress leaves preserved for 13 days at 5 °C. The respiratory rate was reduced by the non-conventional atmosphere up to 3 days of storage, and no significant effects were observed on C₂H₄ production. In addition, mesophilic microbial growth was reduced up to 3 days of storage, and no effect was observed on psychrotrophic and Enterobactericeae counts. He and N₂O atmospheres increased the antioxidant activity of watercress at the end of the storage period. Nevertheless, there was no clear effect of non-conventional gases on the color parameters, polyphenol contents and sensory parameters of fresh-cut watercress.     

东亚钳蝎对小菜蛾的捕食效应

在实验室条件下，研究东亚钳蝎对小菜蛾的捕食效应。结果表明，东亚钳蝎对小菜蛾3~4龄幼虫及成虫的捕食功能反应属于Holling 功能反应模型Ⅱ型，对幼虫和成虫的瞬间攻击力分别为0.661和0.687，最大捕食量则分别为36.36头和125头。东亚钳蝎有较强的种内干扰作用，随着捕食者密度的增大，捕食作用率相应降低。猎物和天敌相互干扰会降低东亚钳蝎对3~4龄小菜蛾幼虫的寻找效应，但对其捕食量影响不大。在小菜蛾幼虫和成虫的混合种群中东亚钳蝎偏嗜小菜蛾成虫。