营养与衰老关系研究

指出了营养是人在整个生命过程中保持和提高健康状况的重要因素之一,营养的改善有助于降低慢性疾病的患病风险和延长寿命。研究发现卡路里限制能够延长一些生物的寿命,延迟衰老特征的产生,卡路里限制是通过调节表观遗传、细胞生长、衰老信号及细胞间传递信号分子来诱导细胞和整个机体水平上的衰老应答。适应性衰老应答可以使细胞和机体抗年龄有关的机体变化促进长寿。在人体中,卡路里限制能够抵抗癌症、糖尿病、动脉粥样硬化、心血管病和神经组织退化等慢性疾病的发生与发展从而促进人类的长寿。     

改性粘土对天然橡胶／粘土复合材料抗氧老化性能的影响

采用高分子包复剂、硅烷偶联剂、钛酸酯偶联剂，并结合使用氧剂对粘土进行改性处理，制备相应的粘土胶进行热氧老化、光氧老化及臭氧老化性能测试。结果表明，高分子包复剂、抗氧剂及偶联剂产生协同作用；大大提高了粘土胶抗热氧老化及光氧老化性能，而新型胺类防老剂与钛酸酯偶联剂共同使用，可使粘土胶抗臭氧老化性能提高50%。     

Effects of boning method and postmortem aging on meat quality characteristics of pork loin

This work investigated the effects of boning method and postmortem aging on pork loin color, shearing value and sensory attributes. Two experiments were assigned. In Experiment I, 30 Chinese native black pigs were slaughtered and their carcasses were divided into three groups: (i) hot-boning: carcasses were fabricated within 45 min postmortem just after dressing; (ii) cold boning at 24 h: carcasses were fabricated after chilling at 0°C for 24 h; (iii) cold boning at 36 h: carcasses were fabricated after chilling at 0°C for 36 h. In Experiment II, right sides of the second group in Experiment I were used and primal cuts were vacuum packed and aged for 1 day, 8 days and 16 days. Pork loins ( Longissimus lumborum ) were used for color measurement, shearing test, and sensory evaluation. Among three boning methods, cold-boning at 36 h postmortem had the advantages of giving muscles a better color, the lowest cooking loss and cooked shearing value, and the highest sensory tenderness, juiciness, flavor and overall liking. Postmortem aging could improve pork quality characteristics, but it is not the fact that the longer aging time is, the better pork quality would be. Eight days may be enough to obtain an acceptable sensory attribute. These results are meaningful for pork processing and pork consumption.     

The influence of aging and low zinc nutrition on the choroid in the pig: I. The melanocyte

The effects of low zinc nutrition and aging on central choroidal melanocytes were examined in the pig. Three populations of pigs (young, pregnant and aged), were maintained on either control (C) or low zinc (LZ) diets. Twenty-five weanling boars were sacrificed at 2, 4, 8, 10, and 12-month intervals, and nine pregnant sows and eight aged sows were sacrificed after a 6-month interval. Melanocytes of the central choroid were morphologically and morphometrically examined. The melanocyte was found to be conservative in its form, which was mostly elliptical longitudinal profile, throughout the different age populations that were fed the C diet. Morphometric observations revealed that this cell type increased in size in the oldest animals, having been 40% greater than that in the younger two populations. However, the overall percentage area occupied by melanocytes remained the same throughout all age groups. In the animals that were fed the LZ diets, a large subpopulation of choroidal melanocytes was oval to round in shape in the pregnant and aged groups. Many members of this subpopulation possessed less opaque pigment than the elliptically shaped cell. Measurements of the size and percentage area occupied in these oldest groups increased significantly. In addition to the change of size, shape and melanin opaqueness, unusually large melanosomes were consistently observed in the pregnant and aged LZ groups. Low zinc nutrition had a remarkable age-related impact on the usually quiescent melanocyte.     

The influence of aging and low zinc nutrition on the choroid in the pig: II. The melanosome

The effects of low zinc nutrition and aging on central choroidal melanosomes were examined in the pig. Melanosomes of central choroidal melanocytes were morphologically and morphometrically examined in three populations of pigs (young, pregnant and aged), that were maintained on either control (C) or low zinc (LZ) diets. In C groups, the typical melanosomes decreased in size with age, although a subpopulation of larger melanosomes occurred in the oldest group. In contrast, the melanosomes of the animals on LZ diets increased in size significantly in the adult groups. The melanosomes in the pregnant and aged groups were 65% and 30–40% greater than those of the age-matched C groups. Extremely large melanosomes were frequently encountered in adult LZ choroidal melanocytes. Melanogenesis of these large bodies included the formation of one or more outer shells. Fusion of adjacent large melanosomes was also observed. Melanolysosomal-like bodies were observed, particularly among the pigmented cells in the large blood vessel region of C and LZ adults. Melanin dynamics, i.e. its production and breakdown, occurred within choroidal melanocytes throughout much of the lifespan of the pig. This dynamic was greatly influenced by low zinc nutrition, resulting in unusual and aberrant melanin activity.     

积极老龄化背景下安徽省养老服务政策研究——基于2002—2022年政策文本的分析

在积极老龄化背景下,推动养老服务政策优化升级是新时代老龄社会治理的迫切需要。运用文献计量法和内容分析法,从外部要素和内在属性两方面,对安徽省2002-2022年39份政策文本进行综合量化研究发现,养老服务政策发展历经三个时期;发文主体之间是跟随型府际关系与协作型府际关系并存的合作模式;养老服务政策可执行性和可操作性有待加强;“老有所养”“老有所医”是养老服务政策核心;养老服务政策工具使用结构失衡。未来制定养老服务政策要坚持问题导向,加强协作配合;强化需求认识,拓展需求空间;健全政策工具协调网络,规划合理工具组合方式。     

对当前农村养老问题的思考

论述了我国农村养老面临的诸多挑战,根据当前农村养老的实际状况,提出了改善我国农村养老保障的对策和建议。     

罗布麻种子老化过程中的生理生化特性

罗布麻（Apocynum venetum）集中成片分布于盐碱、沙荒地区,耐寒耐旱,耐盐碱耐风沙。自然严酷条件下,罗布麻种子活力变化对其种群的环境适应性具有重要影响,因此采用人工老化的方法,研究其在逆境条件下的生理变化,可探明罗布麻种子活力的劣变规律、种群的扩繁机制以及罗布麻种子的贮藏特性和寿命。在相对湿度100%、温度分别为35 ℃和50 ℃的条件下,对罗布麻种子处理84 h,测定其生理生化指标。结果表明,在相同温度下,随着老化时间延长,种子电导率在初期先下降后升高,脱氢酶、过氧化物酶逐渐降低,浸出液可溶性糖逐渐升高。老化温度越高,对种子造成的影响越大。罗布麻种子对高温逆境在生理上有响应,种子抗热性较强。     

EVA的老化机理及其对眼镜镜片的影响

论述了EVA(乙烯和醋酸乙烯酯的共聚物)的热老化机理和其老化现象,分析了老化现象对眼镜镜片质量的影响,总结了EVA作为眼镜生产用密封圈材料的改进方法。     

微生物在烟叶发酵过程中的作用

目的微生物在提高烟叶品质和生产天然香精香料中均具有重要的意义。本研究探究了烟叶中分离出的产香菌株的产香特性,以及菌株的应用特征。以期为该菌株的应用提供研究基础。方法应用烟叶浸提物培养基对醇化初期的烟叶表面细菌进行了分离,并通过发酵产香筛选得到1株具有明显香味的细菌M-5,采用分子生物学方法对产香菌株M-5进行了初步鉴定,并利用气相色谱—质谱(GC-MS)联用技术分析了发酵液的香气成分。结果菌株M-5被初步鉴定为蜡样芽孢杆菌(Bacillus cereus),进一步分析菌株M-5利用烟叶发酵液的香气成分,其所产生的香气物质较多,主要有2,3-丁二醇(23.89%)、苯乙酮(9.04%)、苯乙醇(8.13%)、丁酸乙酯(6.07%)、乙酸丁酯(4.46%)和棕榈酸(2.82%),这些物质在改善烟叶品质和香精香料中都有应用。结论M-5菌株不仅在烟叶醇化中被用于提高烟叶香气、改善烟叶吸味等,还在制备烟叶香料香精方面有着潜在的应用前景。