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1.
土地开发整理前期地形图测绘调研分析   总被引:4,自引:1,他引:3  
田茂强  杨宝佳  方广贺  杨伟 《安徽农业科学》2011,39(27):16946-16947
通过对重庆市彭水县高谷镇共和村土地开发整理测绘项目的实地调研分析,对该项目进行了归纳总结,介绍项目的测绘技术和流程,旨在为今后推进农村土地开发整理测绘提供实践依据。  相似文献   
2.
我国2004-2015年交通事故影响因素实证研究   总被引:2,自引:1,他引:1       下载免费PDF全文
我国每年因交通事故造成巨额生命财产损失,严重危害公民健康,给经济建设和社会和谐稳定带来重要影响.道路交通安全处于动态平衡过程,经济因素对道路交通安全有重要影响.该文研究2004-2015年交通事故伤亡人数变化规律,并运用统计学分析方法,探索GDP、人均可支配收入、汽车拥有量、交通投资、道路通车里程和直接财产损失等因素变化对交通事故伤亡人数变化的影响.结果表明:国内生产总值、汽车拥有量、交通投资、道路通车里程等影响因素变化率与道路交通事故死亡人数增长率有显著相关性,其中国内生产总值、道路交通投资和道路通车里程增长率与道路交通事故死亡人数增长率呈负相关,而汽车拥有量与道路交通死亡人数增长率呈正相关.  相似文献   
3.
为解决土地适宜性评价中因子权重选取的主观性和随意性问题,以夏橙产区为例,引入模糊证据权法.评价结果显示:85%的已知适宜点处于修正后验概率分级图的中等适宜级别以上,表明集数据驱动和知识驱动为一体的模糊证据权法与修正后验概率模型结合可以客观、准确地对土地进行适宜性评价.  相似文献   
4.
Aiming at the problem of reasonable decorate of coal gas extraction drilling, combining with the initial and boundary condition of borehole extraction, the solid and gas coupling mathematical model of gas seepage of borehole extraction is deduced based on established control equations of seepage field and deformation field. Taking gas extraction of stone coal slit as an example, according to the characteristics of coal seam in the research, the numerical simulation method is used to obtain the distribution rule of gas pressure, coalbed gas permeability, and coalbed gas seepage velocity as well as seam deformation. The effective radius of gas extraction drilling of single bedding about mining-coal bed is determined, which provides the basis for optimum arrangement of gas extraction drilling of single bedding. The results show that the effective radius of stone coal is about 4 m. If the prolonging drilling drainage time is less than 20%, the drilling quantities would reduce by about 50%.  相似文献   
5.
低能氮离子注入桔梗种子的生物学效应研究   总被引:1,自引:0,他引:1  
李颖  唐凌  梁国鲁  吴頔  党江波  项萱 《核农学报》2019,33(6):1065-1071
为研究低能氮离子(N+)注入对桔梗种子的生物学效应,以不同氮离子注入能量(25 KeV和35 KeV)和剂量[0(CK)、2×1016、4×1016、6×1016、8×1016、10×1016、12×1016N+·cm-2]对桔梗种子进行处理,通过测定M0存活率探索最佳处理条件,并对桔梗进行形态学性状观察,筛选优异突变株,进一步通过ISSR分子标记分析桔梗突变体突变位点。结果表明,能量为25 KeV,剂量为12×1016 N+·cm-2时,桔梗存活率最高,为77.0%。突变株的花形、花萼结构、花期和株高均发生了变化,主要表现为花萼向类似花瓣结构变化、花期延迟、植株变矮等;突变株的ISSR分析结果显示,20对引物共扩增出250个位点,其中多态性位点共87个,多态率为34.80%,平均每对引物可扩增出4.35条多态性片段。本研究结果为桔梗N+注入诱变育种提供了一定的理论参考。  相似文献   
6.
为了研究Bax可能形成的在细胞凋亡中起作用的蛋白复合体,选择Bcl-2家族中的前凋亡因子Bax作为诱饵蛋白,对17.5 d小鼠cDNA文库进行酵母双杂交筛选和BLAST,找到1个RACK1蛋白。为进一步验证上述酵母中Bax与RACK1的结合,用Bax与RACK1的真核表达载体,以免疫共沉淀和免疫荧光染色验证其相互作用。利用293T细胞过量表达Bax和RACK1蛋白,收获裂解液后进行免疫共沉淀试验,结果表明,Bax和RACK1在体内仍可形成复合体;在293T细胞中共转Bax和RACK1质粒,用各自荧光抗体标记,然后用激光共聚焦显微镜观察,发现Bax和RACK1可以共定位。  相似文献   
7.
文卓立  于清 《安徽农业科学》2010,(25):13786-13789
在重庆缙云山选择典型、有代表性的不同演替阶段的植物群落,进行植被调查和土壤抗蚀性分析。通过因子分析,提出了可反映特征根大部分信息(89.2%)的3类公因子,并以3类公因子对应的方差贡献率为权数计算出10个植物群落土壤抗蚀性的综合得分。其中先锋群落的土壤抗蚀性最好,顶级群落和过渡类型后期植物群落的土壤抗蚀性次之,先锋森林的土壤抗蚀性最差。  相似文献   
8.
AIM: In order to investigate the mechanisms involved in the vascular hyporeactivity after hemorrhagic shock, the changes of Ca2+ release from calcium store in vascular smooth muscle cells (VSMCs) with hypoxia were observed and the role of Ca2+ release from calcium store in the occurrence of vascular hyporeactivity to norepinephrine (NE) after hemorrhagic shock in rats was further explored.METHODS: A hemorrhagic shock model (40 mmHg for 2 h) in rats and a VSMCs hypoxic model were established. The changes of intracellular Ca2+ concentration in VSMCs were evaluated by fura3-AM and the role of IP3R and RyR mediated Ca2+ release from calcium store was further observed. The role of IP3R and RyR mediated Ca2+ release from Ca2+ store in the development of vascular hyporeactivity was measured with an isolated organ perfusion system. RESULTS: In the absence of extracellular Ca2+, NE upregulated by mobilizing Ca2+ release through calcium store. Compared to the normal control, the VSMCs had a slight increase when treated with hypoxia and NE-induced intracellular down-regulated, both without significant difference. Compared to the normal control cells, there was a significant change of Ca2+ release from calcium store in hypoxia-treated VSMCs, characterized by the significant increase in triggered by RyR-sensitive Ca2+ releasing activator caffeine. However, the increase in triggered by IP3R-mediated Ca2+ release agonist adenophostin A (10-5 mol/L) and ATP-Na2 (10-4 mol/L) had no significant difference in hypoxic VSMCs. Furthermore, the vascular reactivity to NE decreased in abdominal aorta in hemorrhagic shock (40 mmHg, 2 h) rats. The activation of IP3R mediated Ca2+ release with ATP-Na2 (10-4 mol/L) did not improve the vascular reactivity to NE, while inhibition of IP3R mediated Ca2+ release with heparin (104 U/L) significantly antagonized the vascular reactivity to NE in hemorrhagic shock rats. In addition, in normal K-H solution (with about 2.2 mmol/L) and Ca2+-free K-H solution, RyR antagonist ryanodine (10-5 mol/L) partly restored the vascular reactivity to NE in hemorrhagic shock rats, while RyR agonist caffeine(10-3 mol/L) further decreased the vascular reactivity. CONCLUSION: The over-activation of RyR-mediated Ca2+ release from calcium store is partly involved in the development of vascular hyporeactivity after hemorrhagic shock in rats.  相似文献   
9.
Based on structural deformation analysis, we developed calculation models of externally prestressing tendon stresses increments for simply supported beams on service loads. The Windows program SICPEM for calculating stress increments, based on energy principle, was programmed using the object oriented method. Six beams results, tested by Tan, and the free length of externally straight tendons were recomputed by the program. The ratio of computed results to test results is 0.895, and the standard deviation is 0.013. Furthermore, the free length of externally straight tendons, for which the second order effect can be ignored safely, is ten times beam depth. This coincides with the reference literature.  相似文献   
10.
AIM: To explore whether A3 adenosine receptor plays a role in the modulation of vascular reactivity after hemorrhagic shock in rat, and to find out the prospective drug target to restore the decreased vascular reactivity following hemorrhagic shock. METHODS: The hemorrhagic shock (40 mmHg) model was established in rat, and the reactivity of superior mesenteric artery (SMA) to norepinephrine (NE) was observed. A3AR expression at protein level and mRNA level were measured by Western blotting and RT-PCR respectively. RESULTS: The vascular reactivity of SMA to NE after hemorrhagic shock (40 mmHg) was decreased significantly in a biphasic response manner. The expression of A3AR mRNA in SMA after hemorrhagic shock decreased without significant difference. The expression of A3AR protein has a slight increase without statistical difference after 30 min of hemorrhagic shock and then has a significant decrease (especially at 2 h and 4 h after hemorrhagic shock). The usage of IB-MECA, a selective A3AR agonist, significantly increased the responsiveness of SMA to NE in hemorrhagic shock in rat. MRS1523, the selective A3AR antagonist, significantly abolished the restoration of the vascular reactivity to NE by IB-MECA in hemorrhagic shock in rat. CONCLUSION: A3AR plays a role in the modulation of vascular responsiveness to NE in hemorrhagic shock in rat, and the selective agonist of A3AR could restore the reactivity of SMA to NE in hemorrhagic shock in rat.  相似文献   
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