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91.
利用RACE技术从蚤状溞(Daphnia pulex)中克隆到Hsp90基因cDNA全长为2568bp,开放阅读框为2155bp,编码718个氨基酸残基,Hsp90蛋白中存在GxxGxG、LxxLL模块(亮氨酸拉链)和C末端的MEEVD序列。同源性比对结果显示蚤状溞Hsp90基因与日本对虾和刀额新对虾的同源性最高为85%,与其它甲壳纲物种的同源性保持在79%及以上。进化分析发现,蚤状溞Hsp90基因与剑水蚤、日本沼虾、红螯相手蟹等甲壳纲的亲缘关系最近。用Real Time PCR技术,检测了Hsp90mRNA在蚤状溞不同生殖状态下的表达水平:Hsp90 mRNA在两性溞(带冬卵)中的表达量明显高于孤雌溞(带夏卵)(P0.05),且在冬卵中的表达量最低。推测Hsp90可能参与了蚤状溞的生殖转化调控。Hsp90 mRNA在雄溞中的表达量是孤雌溞的2.4倍,说明Hsp90可能参与了精子的形成过程。  相似文献   
92.
The imposition of exclusive statutory real property rights in or near pastoralists’ areas and their migration corridors permanently excludes and extinguishes pastoralist rights to mobility and access to required resources. Seasonal interactions with non-pastoralist land use actors often occur during pastoralist migrations between rangelands and highlands or dry season grazing areas. In an embedded case study in Northern Kenya, in which interviews based on semi-structured questionnaires were held with pastoralists and non-pastoralists, we investigated how non-pastoralist land use actors manage encounters with migrating pastoralists within the context of the Land Administration system. We found that the majority of non-pastoralist land use actors encounter migrating pastoralists during distinct periods. Most never allow herders access to privately owned land. A small proportion allow access and make temporary verbal or written access agreements containing provisions on grazing fees, grazing regulations and rules to protect private property. The majority of non-pastoralists are unwilling to have access arrangements formalized. We argue that land rights adjudication should identify and confer all existing land rights to all users to avoid obstruction or renegotiation for access, and recommend the inclusion of pastoralists’ access rights as real property rights in the Land Administration system.  相似文献   
93.
The Main Frontal thrust (MFT) uplifts the Himalayan topographic front. Deciphering MFT deformation kinematics is crucial for understanding how the orogen accommodates continuing continental collision and assessing associated hazards. Here, we (a) detail newly discovered fault-zone exposures along the MFT at the Mohand Range front in northwestern India and (b) apply contemporary fault zone theory to show that the MFT is an emergent fault with a well-developed fault zone overlain by uplifted Quaternary gravels over a horizontal length of ∼700 m. Northward from the front, the fault zone grades from a central, gouge-dominated core to a hanging-wall, rock-dominated damage zone. We observed incohesive, non-foliated breccia, fault gouge, and brittle deformation microstructures within the fractured country rocks (Middle Siwaliks) and outcrop scale, non-plunging folds in the proximal hanging wall. We interpret these observations to suggest that (1) elastico-frictional (brittle) deformation processes operated in the fault zone at near surface (∼1–5 km depth) conditions and (2) the folds formed first at the propagating MFT fault tip, then were subsequently dismembered by the fault itself. Thus, we interpret the Mohand Range as a fault-propagation fold driven by an emergent MFT in contrast to the consensus view that it is a fault-bend fold. A fault-propagation fold model is more consistent with these new observations, the modern range-scale topography, and existing erosion estimates. To further evaluate our proposed structural model, we used a Boundary Element Method-based dislocation model to simulate topographic growth from excess slip at a propagating fault tip. Results show that the frontal topography could have evolved by slip along a (a) near-surface fault plane consistent with the present-day MFT location, or (b) blind MFT at ∼3 km depth farther north near the drainage divide. Comparing modelled vs. measured high resolution (∼16 cm) topographic profiles for each case provides permissible end-member scenarios of an either dynamically-evolving, high erosion, northward-migrating frontal scarp or a static, low, and symmetric, MHT-related fold, respectively. Our integrated approach is expected to deliver an improved understanding of coupled fault-generated deformation and topographic growth that may be applied more broadly across the entire Himalayan front.  相似文献   
94.
范喜秋 《山东地质》2010,(12):43-45
国家出台的房地产紧缩政策,有效遏制了一线城市房地产市场的过热势头,但同时也制约了诸如烟台市这样的三线城市的市场交易,尤其是一些合理的改善型需求也得到遏制,导致房地产交易明显下降。该文通过对近几年烟台市房地产市场的的量化对比和综合分析,提出加强房地产用地调控力度的重要性以及对策措施,对新形势下如何协调国家房地产紧缩政策与房地产市场的平稳健康发展具有良好的借鉴价值。  相似文献   
95.
张先  虎喜凤 《地震研究》1995,18(1):63-67
依据频率域磁化强度反演方法和程序,对唐山滦县震区航磁资料进行了数据处理,求取了该区视磁化强度的水平分布。反演结果反映了震区地壳内不同规模、不同物性的地壳岩体在平面上的投影。本文结合唐山滦县震区地震的时空分布及破裂方向,对该区地震的孕育及发生过程进行了探讨。  相似文献   
96.
山东省区域经济发展状况GIS评价   总被引:1,自引:0,他引:1  
肖燕  孙壮 《测绘科学》2012,37(5):145-147
本文利用山东省2003年-2009年县市人均生产总值等经济数据,借助SuperMap的GIS空间分析功能进行山东省区域经济发展状况分析。方法上将单纯的统计数据与实际地理位置相关联。结果表明:山东省近7年间县域人均收入分布明显不均匀,呈现不利于经济长期持续发展的单峰分布状态;区域间的人均生产总值差距逐渐增加;人均生产总值与地理区位、资源分布和交通线路的分布有较大相关性。  相似文献   
97.
何谷先 《湖南地质》1990,9(2):74-76
工业指标是矿床勘探、开发的依据,是矿床经济评价、矿山生产调节和取得最好经济效益的基本因素。因此,在地质勘探、矿山开发的各个阶段,最需选择最佳工业指标,以保证资源的合理开发利用。笔者通过湘西某矿山的各项技术经济指标的实施情况,按收支平衡法计算了金、锑、钨的最低工业品位,不但扩大了矿山保有储量,而且找出了生产管理上的弊病,从而保证了矿山最好的经济效益。  相似文献   
98.
Forecasting of ocean wave heights, with warning time of a few hours or days, is necessary in planning many operation-related activities in the ocean. Such information is currently derived by numerically solving the differential equation representing wave energy balance. The solution procedure involved is extremely complex and calls for very large amounts of meteorological and oceanographic data. This paper presents a complementary and simple method to make a point forecast of waves in real time sense based on the current observation of waves at a site. It incorporates the technique of neural networks. The network involved is first trained by different algorithms and then used to forecast waves with lead times varying from 3 to 24 h. The results of different training algorithms are compared with each other. The neural output is further compared with the statistical AR models.  相似文献   
99.
城市交通与房地产开发的关联与协调——以广州市为例   总被引:2,自引:0,他引:2  
李文翎 《热带地理》2003,23(4):354-358
分析广州市房地产开发与交通发展的特征和城市交通与房地产开发间的相互关系,论述了房地产开发对交通的诱导作用和交通对房地产开发的影响.在此基础上,提出城市交通与房地产业开发协调发展的策略.  相似文献   
100.
烟台市不动产数据整合建库关键技术研究   总被引:1,自引:0,他引:1  
通过全面收集土地、房屋、林业、海域登记图形、属性和档案数据,实施清理、外业核查、信息补录等工作,得到完整、齐全的数据。按照建库标准和入库要求,对所有数据进行统一转换,分别对土地和房屋的图形数据、属性数据及档案数据建立一一对应关系,并开展关联校验工作。将土地和房屋各自关联后的数据成果进行空间逻辑组建及权属关联,实现"房地合一"。按照不动产数据库设计规范要求,将已整理完备的不动产数据统一入库,为不动产相关业务系统提供基础数据资源。  相似文献   
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