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991.
非洲企鹅(Spheniscus demersus)是一种濒危海鸟,也是动物园展出的重要物种。上海动物园从日本和荷兰引进非洲企鹅,种群不断扩大,并成为国内种群发展的基础。但对其遗传多样性和结构了解很少,无法开展有效的遗传管理。本研究分析了上海动物园39只非洲企鹅的mtDNA D-loop区430 bp序列,并与已发表的日本种群的数据进行比较。结果表明,该片段存在15个变异位点,占分析位点的3.5%;共定义了10个单倍型,其遗传距离为0.002~0.019。日本种群包含A、B两个mtDNA D-loop单倍型世系,上海种群的10个单倍型均属于A世系,且与日本种群有5个共享单倍型,其遗传多样性水平略低于日本种群。上海种群可以进一步分为3个小的世系,但置信度偏低(54%~87%)。上述结果提示,上海种群相对于日本种群的A世系而言有较好涵盖度,但仍有必要进一步引进建群个体,尤其是含有B世系单倍型的个体。 相似文献
992.
加工方式对非发酵面团小麦醇溶蛋白致敏性的影响 总被引:2,自引:2,他引:0
该研究探究了热加工(水煮、烘烤、微波、高温高压)、冷处理(液氮、速冻机速冻)和非热加工(超高静压、辐照、脉冲强光、臭氧和超声波)处理对非发酵面团小麦醇溶蛋白致敏性的影响。利用SDS-PAGE和双抗体夹心ELISA法研究各种加工处理后非发酵面团小麦醇溶蛋白的分子量和致敏性变化。结果表明:200和300 MPa的超高静压处理后,非发酵面团小麦醇溶蛋白的致敏性显著增加(P0.05),均增至125%左右;水煮、微波、高温高压、烘烤、液氮、速冻机处理、超高静压250MPa、辐照(7、13kGy)、臭氧熏蒸、脉冲强光和超声波处理均能显著降低非发酵面团小麦醇溶蛋白的致敏性(P0.05),其中以水煮、高温高压、液氮、臭氧和脉冲强光(PL-1)处理的脱敏效果最显著(P0.01),均降至60%左右。由此可知,加工方式能够显著影响非发酵面团小麦醇溶蛋白的致敏性,可作为食品中过敏原安全控制的有效手段,为脱敏食品的生产提供有效参考。进一步研究需要结合其他体内试验的评估,特别是小麦易敏人群的临床试验。 相似文献
993.
994.
A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible. 相似文献
995.
This research aims to make an analysis of energy use efficiency of apple (‘Starkrimson Delicious’ and ‘Golden Delicious’) production in E?irdir region of Turkey, during the production season of 2012. Production data this research was collected in 2013. In order to determine the energy use efficiency of apple, various surveys have been conducted in 71 apple farms, selected through Simple Random Sampling method, located in E?irdir region of Turkey. The data have been collected through face to face questionnaires and first hand observations. The energy input and output values in apple production have been calculated as 34,703.63 MJ ha?1 and 95,034 MJ ha?1, respectively. Energy inputs consist of diesel fuel energy by 29.04?%, chemical fertilizers energy by 24.28?%, machinery energy by 15.70?%, chemical energy by 9.84?%, human labor energy by 8.54?%, electricity energy by 5.63?%, irrigation energy by 3.97?%, farmyard manure energy by 2.88?% and lime energy by 0.12?%. Energy use efficiency, energy productivity, specific energy and net energy in apple production have been calculated as 2.74, 1.16 kg MJ?1, 0.86 MJ kg?1 and 60,330.36 MJ ha?1, respectively. The total energy input consumed has been classified as direct, by 47.17?%, indirect, by 52.83?%, renewable, by 15.38?% and non-renewable, by 74.62?%. 相似文献
996.
土地采用保护性耕作方法,可有效的防止水土流失,增加土壤蓄水能力,提高雨水利用率,培肥地利,增加土壤有机质,减少耕作次数,降低生产成本,各种农作物增产明显。 相似文献
997.
998.
王顶言 《农业装备与车辆工程》2011,(8):3-5
为促进浙江省农业机械装备产业又好又快发展,在分析浙江省农机装备产业发展的特色和产业发展中存在的问题基础上,根据当今国内外农机装备与技术发展趋势和国内外市场需求,提出了加快浙江省农机装备产业发展的相关措施与建议。 相似文献
999.
Juan Jin Huimei Cui Xinmin Lv Yifan Yang Yi Wang 《The Journal of Horticultural Science and Biotechnology》2017,92(1):98-106
In this study, we investigated the effects of 10 mM CaCl2 on membrane permeability, malondialdehyde (MDA), reactive oxygen species (ROS), and Na+, K+, Ca2+, and Mg2+ concentrations in different organs of sour jujube grown under 150 mM NaCl stress. Our results showed 73% leaf wilting in the Na treatment. The Na treatment significantly increased leaf superoxide (O2.?) production rates, hydrogen peroxide (H2O2) concentrations, cell membrane permeability, MDA concentrations, and Na+ concentrations in roots, stems, and leaves. The Na treatment significantly reduced K+, Ca2+,and Mg2+ concentrations in roots, but increased K+ concentrations in stems. Compared with the Na treatment, 39% of the leaves showed wilting symptoms in the Na+Ca treatment. The Na+Ca treatment significantly decreased leaf O2.? production rates, H2O2 concentrations, cell membrane permeability, and MDA concentrations. Moreover, the Na+Ca treatment (1) significantly reduced Na+ concentrations in roots, stems, and leaves; (2) significantly increased root K+ concentrations; (3) significantly increased K+/Na+ ratios in roots; (4) significantly increased Ca2+ concentrations in stems and leaves, and Mg2+ concentrations in roots. In conclusion, exogenous CaCl2 reduces NaCl stress in sour jujube by reducing Na+ concentrations and increasing K+, Ca2+, and Mg2+ concentrations in various plant organs. 相似文献
1000.