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11.
依据信息安全等级保护有关政策和标准,结合费县国土资源局信息化建设中涉密计算机管理工作实际,探讨如何从计算机信息输入和输出2个方面有效预防计算机失窃密。从计算机身份认证与访问控制、网口、UBS口电磁辐射,办公设备5个方面分析泄密隐患,并提出相应的应对措施,强调了在国土资源系统涉密计算机管理方面要加强保密意识,提高防范技能。  相似文献   
12.
对许氏平鲉进行简化基因组测序,设计微卫星引物200对,可稳定扩增的引物190对,占95%。利用一个荣成野生群体对24个多态性较高的微卫星标记进行了评价,每个位点的等位基因数(Na)为2—21个,观测杂合度(Ho)为0.0417—0.9167,期望杂合度(He)为0.0278—0.9722,多态信息含量(PIC)为0.1948—0.9496,结果显示有20个微卫星位点为中高度多态。利用这些引物对荣成野生群体和烟台养殖群体的遗传多样性进行了比较分析,野生和养殖群体的平均等位基因数(Na)分别为8.5000、6.9583,有效等位基因数(Ne)的均值分别为4.5484、3.6365,期望杂合度(He)均值分别为0.6421、0.5840,多态信息含量均值(PIC)分别为0.6088、0.5490,平均香农-威纳指数均值为1.4605、1.2834,但F检验发现无显著差异,发现两个群体的遗传多样性都处于高度多态水平,但养殖群体遗传多样性水平低于野生群体。本研究结果说明许氏平鲉的人工繁育中,通过使用较大数量的亲本进行繁育可有效防止选育群体的遗传多样性降低,但人工定向选育对选育群体的遗传多样性也产生了一定的影响。Bonferroni校正后在两个群体中各有4个位点偏离Hardy-Weinberg平衡。本研究开发的微卫星标记为许氏平鲉遗传图谱构建、分子标记辅助育种等提供了更多标记选择,对野生和养殖群体遗传多样性分析为下一步的遗传育种提供参考。  相似文献   
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Despite great achievements in the origins of domestic pigs made by the methods of zooarchaeology and molecular biology, how to scientifically distinguish the domesticated pigs from wild boars during the early stage of pig domestication is still poorly understood. Compared to wild boar’s diets which come from the natural environment, the diets of domestic pigs are more easily influenced by human feeding activities. Therefore, in principle, exploration of the dietary differences among pigs and under-standing the impact on pig diets fed by humans can have great potential to differentiate between wild boars and domesticated pigs. To reveal dietary differences among pigs and distinguish the domesticated pigs from wild boars based on comparison with the diets of humans and other animals, we analyzed the carbon and nitrogen stable isotopes of human bones from Xiaojingshan Site and animal bones from Yuezhuang Site, both of which belong to Houli Culture in Shandong Province and date to about 8500-7500 years ago. The mean δ13C value ((−17.8 ± 0.3)‰) and δ15N value ((9.0±0.6)‰) in human collagen indicate that although millet agriculture began it was not the main subsistence strategy as millets are typical of C4 plants and that humans made a living mainly by gathering, hunting or raising some domesticated animals. The δ13C value (−16.1‰) and δ15N value (6.9‰) in the bovine suggest that C3 plants were dominant in its diet with some C4 plants complemented. The fish has lower δ13C value (−24.9‰) and higher δ15N value (8.8‰) than the bovine, which is the characteristic of the isotopic values from Eurasian freshwater fish. Based on the differences in carbon and nitrogen isotope values, the pigs can be divided into three groups. A group, composed of two pigs, has low δ13C values (−18.1‰, −20.0‰) and low δ15N values (4.7‰, 6.0‰). B group, only one pig, has the highest δ13C value (−10.6‰) and mediate δ15N value (6.4‰). As for the C group, also only one pig, low δ13C value (−19.0‰) and the highest δ15N value (9.1‰) are observed. Previous studies on the stable isotopes from modern or ancient wild boars’ bones have suggested that C3 plants are predominated in their diets and that their δ15N values are close to those in herbivores and far from those in carnivores. Based on the comparison with the isotope values from humans, the wild boars and the domestic pigs from Xipo Site in Henan 6000-5500 years ago and Kangjia Site in Shaanxi 4500-4000 years ago, we conclude that A pig group belongs to wild boars while B and C groups can be attributed to domesticated pigs. Supported by Max-Planck Society and Chinese Academy of Sciences, Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KJCX3.SYW.N12), National Natural Science Foundation of China (Grant No. 40702003) and President Funding of Graduate University of Chinese Academy of Sciences  相似文献   
15.
青岛浮山野生花卉种质资源   总被引:2,自引:0,他引:2  
本文简要叙述了青岛浮山野生花卉的种类、生长环境、园林用途及开花结果日期,为把这些野生花生花卉引进城市园林提供科学依据。  相似文献   
16.
Dinarides南部是世界上岩溶发育最强烈的地区之一,同时也是欧洲降水量最大的地区。区内碳酸盐岩沉积厚度大于300m,平均岩溶发育深度从250m 至350m,沿断裂发育的岩溶,甚至更深。地下水平均流速变化较大,从0.002 cm/s至55.2cm/s。地下水滞留时间很短,水位变化非常迅速,变幅高达312m。地下水位对强降雨的响应小于4小时。岩溶大泉的主要特征是管道出口深,最大最小流量变化大。区内发育的落水洞有成千上百个,其中一些落水洞排水能力超过100m3/s,规模巨大并被洪水暂时淹没的岩溶坡立谷闻名世界各地。泉水天然流量和野生动物生存环境的改变,特别是当地特有物种的破坏,已经成为新近许多岩溶工程项目的焦点议题。由于该区极其复杂的水文地理和政治环境,不同国度间的跨界含水层似乎是一个非常敏感的问题。  相似文献   
17.
养殖对虾与海捕对虾鉴别方法初探   总被引:1,自引:1,他引:1  
通过对养殖中国对虾(Penaeus orientalis)和海捕中国对虾肌肉煮熟后的失水率,提取物中的甜菜碱和氧化三甲胺含量,以及虾肉脂质中所含脂肪酸组成和含量进行了分析比较,得到下列结果:(1)两类对虾鲜样煮熟后失水率相差6%以上;(2)海捕对虾肌肉中的甜菜碱和氧化三甲胺含量比养殖对虾的高,两者有显著差别;(3)养殖对虾肌肉所含C18:2ω6为17.3±1.5%,海捕对虾为2.0±0.8%。从以上结果本文推荐以脂肪酸C18:2ω6含量来鉴别养殖对虾与海捕对虾。  相似文献   
18.
The wild horse Equus ferus was one of the most frequent species of the Late Pleistocene large ungulate fauna in Eurasia and played an important role in the subsistence of human groups, especially at the end the Late Glacial. It is frequently assumed that E. ferus became extinct in Europe at the beginning of the Holocene because of the development of woodlands and loss of open habitats. Because of its preference for open habitats and in spite of its adaptability, the appearance or disappearance of the wild horse could therefore be a suitable palaeoecological indicator for the opening of the Holocene primeval woodlands. We revised the dating and reliability of the subfossil record and dated several bones by atomic mass spectrometry 14C dating. From the beginning of the Holocene (9600 cal a BC) to the end of the Atlantic Period (3750 cal a BC) there are 207 archaeological sites with wild horse records available in Europe. E. ferus survived the Pleistocene Holocene transition in Europe, but the spatiotemporal dynamics of populations fluctuated remarkably in the early and middle Holocene. Small and sparse populations increasingly became extinct during the early Holocene, until between 7100 and 5500 cal a BC the wild horse was almost absent in central parts of the European Lowlands. Particular conditions in natural open patches in the canopy forests, chalklands and floodplains may have maintained the local survival of the horse in some regions of the Lowlands, however. In the Late Atlantic, between 5500 and 3750 cal a BC the range of the wild horse was again extended. It re‐immigrated into central and western Europe, probably as a consequence of increasing landscape opening by Neolithic peoples. The data presented here may be a valuable part of the debate on the degree of openness of the early and middle Holocene landscape. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
19.
讨论了网箱养殖、工厂化养殖和野生褐牙鲆的外观差异,对比分析了不同生长环境下褐牙鲆的肌肉营养成分和营养学价值。结果显示:网箱养殖的褐牙鲆体形、体色更接近野生褐牙鲆,即有眼侧呈深褐色,无眼侧呈白色;工厂化养殖褐牙鲆有眼侧体色较暗,无眼侧有黑斑。网箱养殖褐牙鲆脂肪含量(2.5%)远低于工厂化养殖的褐牙鲆(4.2%),而接近于野生的褐牙鲆(1.4%);网箱养殖褐牙鲆水分含量比工厂化养殖的高,也更接近野生的褐牙鲆。3种生长环境的褐牙鲆,氨基酸组成是一致的,而且各项比值也都符合FAO/WHO的标准。对比分析必需氨基酸指数(EAAI)和EPA+DPA、SFA、MUFA、PUFA等指标,网箱养殖褐牙鲆均要高于工厂化养殖褐牙鲆,接近而又优于野生的褐牙鲆。在矿物质含量方面,3种生长环境下的褐牙鲆差异不明显。综合各项指标分析,在褐牙鲆的3种生长环境中,网箱养殖的褐牙鲆要优于工厂化养殖的褐牙鲆,而更接近于野生的褐牙鲆。  相似文献   
20.
王灿  吕厚远 《第四纪研究》2012,32(2):269-281
在稻作农业起源和传播的研究中,水稻扇型植硅体对于发现、鉴定水稻遗存起到了重要的作用。目前学术界利用扇型植硅体在区分野生稻和栽培稻,粳稻和籼稻方面建立了诸多判别标准,但这些"标准"并没有得到广泛认可。本文从扇型植硅体的发育机理入手,结合前人对水稻扇型植硅体的研究成果和通过对部分现代野生、栽培水稻扇型植硅体的观察分析,认为尽管现代稻属和粳、籼稻扇型植硅体的鉴定特征是比较明确的,但由于野生稻和栽培稻扇型植硅体的区分存在不确定性,限制了扇型植硅体在早期稻作研究中的应用。本文对目前利用扇型植硅体进行水稻农业考古方面存在的问题进行分析,对如何寻找野生稻和栽培稻扇型植硅体的有效区分标准、如何应用新方法新技术提高鉴定准确性等方面进行了探讨。  相似文献   
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