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71.
为了解橄榄(Canarium album)果实质地差异形成的原因,以鲜食型橄榄‘清榄1号’和加工型橄榄‘长营’为材料,对果实发育过程中细胞壁物质含量和相关酶活性进行了测定。结果表明,随着橄榄果实的成熟,‘清榄1号’较‘长营’维持较高的果胶甲酯酶(PME)活性,促进了果胶的水解,离子型果胶(ISP)含量较高而共价型果胶(CSP)含量较低。2个橄榄品种纤维素含量均较高,‘清榄1号’果实的半纤维素含量低于‘长营’。‘清榄1号’木质素含量低于‘长营’,较高的苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)活性促进了木质素含量的增加。因此,ISP、CSP、半纤维素和木质素含量的不同可能是2个橄榄品种果实质地差异形成的原因。 相似文献
72.
城市热岛(UHI)不仅直接关系到城市人居环境质量和居民健康状况,同时还对城市能源消耗、生态系统过程演变、生物物候以及城市经济可持续发展有着深远的影响。以北京市朝阳区2002—2017年夏季4期Landsat系列遥感影像为数据,采用大气反演法,对15年间朝阳区城市地表温度(LST)时空变化进行分析,发现15年间朝阳区城市热岛比例指数上升迅速,热岛效应逐年加剧。进一步研究表明,城市地表温度与归一化植被指数(NDVI)及归一化建筑指数(NDBI)密切相关:地表温度与NDBI正相关,NDBI指数每升高0.1,地表升温0.79~2.37°C;与NDVI指数负相关,NDVI指数每提高0.1,地表降温0.4~0.77°C。本研究可为城市规划建设与城市绿地营建提供科学具体的参考指导依据,并促进生态可持续发展与人居环境改善。 相似文献
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【背景】黑色素具有抗肿瘤、抗辐射等多种生物活性,在生产和生活中具有巨大的应用潜力,通过真菌生产是获取黑色素的一条重要途径,它与动植物相比具有更短的生产周期和更高的产量,并且易于实现商业应用。【目的】揭示真菌黑色素的生产及应用发展情况和创新趋势,为致力于真菌黑色素产业的科研人员和企业提供参考。【方法】基于Inco Pat科技创新情报平台,通过对全球真菌黑色素相关专利进行检索统计,从专利涉及的菌株、专利技术构成、申请人专利价值等多维度对真菌黑色素相关专利进行深入分析。【结果】真菌黑色素在生产制备领域申请专利数量最多(50.56%),作为化工染料和化妆品原料应用的专利申请数量最少(13.48%),涉及的真菌菌属主要有层孔菌属、短梗霉属、木耳属、纤孔菌属、粒毛盘菌属、灵芝属和曲霉属。目前真菌黑色素专利技术申请的热点领域主要在C12 (微生物发酵、培养基、突变或遗传工程)类和A61 (医学)类,并且在未来一段时间内,C12和A61将继续作为热点技术申请领域。中国申请的真菌黑色素专利数量最多,但拥有的高价值专利比例较低,较国外仍具有一定差距。【结论】我国科研人员需要加强在医药和化工领域核心专利技术的创新应用与海外布局,增强与企业的合作研发和技术转移,以抢占真菌黑色素在这些领域的应用市场,并推动真菌黑色素相关专利向高质量发展。 相似文献
75.
【背景】动物体定殖有多种共生微生物,这些共生微生物严重影响着宿主生理和病理,日益成为研究热点之一。【目的】分离与鉴定黑腹果蝇共生菌,探究表皮葡萄球菌对黑腹果蝇的发育影响和潜在作用机制。【方法】用CEM培养基(Carotenoid expression medium)从果蝇肠道内分离细菌,通过16SrRNA基因序列比对鉴定菌株;以发育时间和幼虫表面积检测果蝇的发育时期和生长速率;利用实时定量PCR检测果蝇促前胸腺激素与胰岛素通路的激活。【结果】从果蝇体内分离到的菌株为表皮葡萄球菌,该菌可以有效定殖于果蝇的肠道。表皮葡萄球菌通过提高果蝇生长速率而显著促进其发育。在分子水平上,表皮葡萄球菌激活PTTH和胰岛素信号以刺激宿主的生长发育。【结论】表皮葡萄球菌是果蝇的一种共生菌,可以通过调控PTTH和胰岛素信号而刺激果蝇生长发育。 相似文献
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The concentrations of airborne fungal spores were measured during 2001–2002 in two sites in Poland—one in the city and the other in the countryside. The sites differed in habitat characteristics, such as urbanisation level, vegetation and microclimate. The aim of the study was to determine if, and in which way, land use type would affect spore occurrence. The volumetric method was used, and ten easily identifiable spore types were sampled and anyalysed: Alternaria, Botrytis, Cladosporium, Epiccocum, Ganoderma, Pithomyces, Polythrincium, Stemphylium, Torula and Drechslera. The season of spore occurrence was determined using the 90% method. The fungal spores studied were very frequent in the air (in most instances at a frequency higher than 50%). The most common spores were those of Cladosporium, with a frequency range of 83.1–90.5%. In both years the proportion of Cladosporium spores was statistically significantly higher in the city. In both 2001 and 2002 the total seasonal sum of all the spores was higher in the countryside than in the city as was the Seasonal Fungal Index (SFI) values and average concentrations of Botrytis, Ganoderma and Torula. These latter three genera are usually represented as pathogens of plants. The mean spore concentrations of most taxa were significantly higher in the rural environment. Correlation coefficients between daily concentrations at both sites for most of the taxa studied were significant, but with lower correlation values between variables. Such results indicate that the values from the sites are weakly interdependent. The study confirms that land use type may very likely have an impact on the course of spore occurrence, the mean daily concentrations of spores as well as SFI values. 相似文献
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79.
Ecology is being introduced to Evolutionary Developmental Biology to enhance organism-, population-, species-, and higher-taxon-level
studies. This exciting, bourgeoning troika will revolutionise how investigators consider relationships among environment,
ontogeny, and phylogeny. Features are studied (and even defined) differently in ecology, development, and evolution. Form
is central to development and evolution but peripheral to ecology. Congruence (i.e., homology) is applied at different hierarchical
levels in the three disciplines. Function is central to ecology but peripheral to development. Herein, the supercategories
form (‘isomorphic’ or ‘allomorphic’), congruence (‘homologous’ or ‘homoplastic’), and function (‘adaptive’ or ‘nonadaptive’)
are combined with two developmental mode (i.e., growth) categories (‘conformational’ or ‘nonconformational’) to provide a
16-class system for analysing features in studies in which ecology, development, and evolution are integrated. 相似文献
80.
Swimming performance of hatchling green turtles is affected by incubation temperature 总被引:3,自引:0,他引:3
In an experiment repeated for two separate years, incubation temperature was found to affect the body size and swimming performance of hatchling green turtles (Chelonia mydas). In the first year, hatchlings from eggs incubated at 26°C were larger in size than hatchlings from 28 and 30°C, whilst in the second year hatchlings from 25.5°C were similar in size to hatchings from 30°C. Clutch of origin influenced the size of hatchlings at all incubation temperatures even when differences in egg size were taken into account. In laboratory measurements of swimming performance, in seawater at 28°C, hatchlings from eggs incubated at 25.5 and 26°C had a lower stroke rate frequency and lower force output than hatchlings from 28 and 30°C. These differences appeared to be caused by the muscles of hatchlings from cooler temperatures fatiguing at a faster rate. Clutch of origin did not influence swimming performance. This finding that hatchling males incubated at lower temperature had reduced swimming ability may affect their survival whilst running the gauntlet of predators in shallow near-shore waters, prior to reaching the relative safety of the open sea. 相似文献