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81.
农机安全监理担负着我国数以千万计的农业机械及其驾驶员的行政管理任务,相应的法律法规要求采用计算机管理系统来对此进行处理并能够及时地将有关信息传送到全国农机监理信息系统。由于全国统一的农机监理信息系统尚未建立,因此提出了构建全国农机监理信息系统数据库标准,即采用B/S模式进行应用程序开发,通过多种网络连接全国各地农机监理业务计算机,从而实现信息共享与网上办公的解决方案。 相似文献
82.
基于CLIPS的农业灌溉专家系统研究 总被引:1,自引:0,他引:1
在干旱区高效用水灌溉决策支持系统研究过程中,农业灌溉过程中的很多问题无法用数学模型来求解,而必须使用农业专家的专家知识来对其进行解答。而早期由于专家系统不普及和开发困难等原因,致使农业灌溉专家系统应用不多。在对现行诸多专家系统进行详细了解后,决定采用CLIPS专家系统作为农业灌溉专家系统的支持平台。采用CLIPS组件和Visual C 语言开发出了农业灌溉专家系统,解决了农业灌溉过程中的诸多问题。同时介绍了将CLIPS组件嵌入到Visual C 中的方法。 相似文献
83.
以一台多缸柴油机为例,采用结合有限元法(FEM)的多体系统仿真(MSS)方法,研究了扭转振动减振器振动对曲轴弯曲、纵向振动的影响;实验测量了有无扭振减振器时的曲轴自由端的弯曲和纵向振动,其与计算结果吻合得较好。 相似文献
84.
ZHANG Qiong WAN Chang-wu YU Yan-ni XIA-Bing LIU Jiang-jin ZHANG Qiao-jun LI Zhu WANG Cheng-fei DAI Jia-lin WANG Jie 《园艺学报》2021,36(12):2133-2138
AIM To explore the possible mechanism of cathepsin C (CTSC) and tumor necrosis factor-α (TNF-α) in coronary heart disease (CHD) by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees (P <0.05). The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group (P <0.05). Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group (P <0.05). The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD (r2 =0.743, P <0.05). CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD. 相似文献
85.
Legume–cereal intercropping is increasingly being appreciated in dryland areas, where severe climatic conditions and intensive agricultural practices, generally dominated by continuous cereal cultivation, determine depletion of soil nutrient resources and decline of soil fertility. This research aimed to assess whether and to what extent a newly introduced legume-based intercropping system is able to ameliorate the biological fertility status of an arable soil in a way that is still noticeable during the succeeding durum wheat cropping season in terms of changes in bacterial community structure, soil C and N pools, and crop yield. A field experiment was carried out under rainfed conditions in Southern Italy on a sandy clay loam soil cultivated with durum wheat following in the rotation a recently established grain legume (pea, faba bean)–barley intercropping. Soil chemical, biochemical and eco-physiological variables together with compositional shifts in the bacterial community structure by LH-PCR fingerprinting were determined at four sampling times during the durum wheat cropping season. Soil fertility was estimated by using a revised version of the biological fertility index. Results showed that even though the microbial biomass was significantly altered, the preceding legume intercrops stimulated C-related functional variables thus leading to an increased release of mineral N, which was larger in crop treatments succeeding pea-based than faba bean-based intercropping. The increased N made available in soil enabled the succeeding durum wheat to achieve an adequate grain yield with a reduced N-fertilizer use. Soil type and environmental conditions rather than crop treatments were major determinants of bacterial community structure. The biological fertility status was not varied, suggesting that in intensively managed rainfed areas long-term crop rotations with intercropped legumes are needed to consistently ameliorate it. 相似文献
86.
Martin Körschens 《Archives of Agronomy and Soil Science》2013,59(2):77-92
Im Statischen Düngungsversuch Bad Lauchstädt werden nach Erweiterung der Versuchsfrage seit 1978 die Prüffaktoren: Stalldung (2 Stufen), Corg‐Gehalt im Boden (6 Stufen) und Mineral‐N‐Mengen (5 Stufen) in der Fruchtfolge Kartoffeln, Winterweizen, Zuckerrüben, Sommergerste geprüft. Nur bei Sommergerste konnte eine Ertragswirkung des Stalldungs im Vergleich zu ausschließlicher Mineraldüngung nachgewiesen werden. Die jährlichen Veränderungen der Corg‐ und Nt‐Gehalte im Boden betrugen bei jeweils extremen Änderungen des Düngungsregimes bis zu 0, 012% Corg bzw. 0,0013% Nt. 相似文献
87.
分析了焊接温度对焊接质量的重要影响,应用传感器技术、温度数据采集技术和计算机通信技术,设计了一种基于AT89C52单片机的温度检测系统。实验结果显示,该系统能够很好地对焊接温度进行采集与处理,为实现研究焊接过程温度场的测量打下了良好的基础。 相似文献
88.
Shingo Mitsui Sueo Aso Kiyoshi Tensho Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(1):17-18
The Foliar Uptake by Squash Plant The radioactive ash for experimental use, hereafter referred to as “Bikini ash”, was prepared by igniting the heavily contaminated substances on board No. 5 Fukuryu Maru at about 650°C, followed by sifting through a 100 mesh sieve. On ignition some parts of the fission products, particularly iodine, ruthenium and tellurium would have possibly been lost to the air. 相似文献
89.
HOU Xiao-min ZHANG Ming-sheng ZHAO Liang-yuan QI Ding-ming QIN Xiao-jiang 《园艺学报》2017,33(10):1801-1805
AIM: To investigate the mechanism of quercetin improving rat coronary artery myogenic response under high glucose (HG) by measuring muscle tension of coronary arterial ring and recording voltage-gated K+ channel (Kv) current of coronary artery smooth muscle cells by whole cell patch clamp. METHODS: The coronary rings from the normal SD rats were acutely isolated, and then divided into 6 groups: (1) control group; (2) HG group; (3) HG+low dose (3 μmol/L) of quercetin group; (4) HG+moderate dose (10 μmol/L) of quercetin group; (5) HG+high dose (30 μmol/L) of quercetin group; (6) HG+C6303 (PKC inhibitor)+high dose of quercetin group. Determinations of coronary artery response to vasoconstrictor (60 mmol/L KCl or 0.1 mmol/L U46619) or vasodilator (ACh at 10-9~10-5 mol/L) were performed, and the percentage of coronary ring tension was calculated using the contraction as 100% caused by 60 mmol/L KCl. The rat coronary artery smooth muscle cells were acutely isolated for recording the Kv current using whole cell patch clamp. RESULTS: Compared with control group, the contraction amplitudes to 60 mmol/L KCl or 0.1 mmol/L U46619 were significantly increased under HG incubation. Quercetin intervention concentration-dependently reduced the coronary artery contraction amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, the diastolic amplitude to ACh decreased significantly in HG group, and quercetin intervention concentration-dependently increased the coronary artery diastolic amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, HG incubation inhibited Kv current of coronary artery vascular smooth muscle cells significantly, and quercetin intervention attenuated the inhibitory effect of HG on Kv current intensity. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. CONCLUSION: Quercetin has a protective effect on myogenic response of coronary artery under HG and the effects is related to the increase in Kv current and the activation of PKC in vascular smooth muscle cells. 相似文献
90.
AIM: To detect the hepatitis C virus (HCV) at early stages by the technique of baculovirus surface display. METHODS: We constructed the recombinant baculoviruses vAc-Flag-HCV C-GP64, vAc-Flag-HCV E-GP64 and vAc-Flag-CE-GP64, which displayed HCV-related structural proteins by the technique of baculovirus surface display. RESULTS: Western blotting results showed that the core (C), envelope (E) and core-envelope (CE) proteins of HCV were expressed in Sf9 cells after the infection of recombinant baculoviruses. We also observed by confocal microscopy that the C, E and CE proteins of HCV presented and were anchored on the plasma membrane of Sf9 cells after infection. In addition, the results of immunogold electron microscopy demonstrated that the 3 recombinant baculoviruses displayed the C, E and CE proteins of HCV on the viral surface, respectively. To further define the role of these recombinant baculoviruses in detecting HCV at early stages, we applied time-resolved fluoroimmunoassay (TRFIA) to detect HCV samples after purification and concentration of the recombinant baculoviruses. The results showed that the positive rate of vAc-Flag-CE-GP64 was up to 80.2%. CONCLUSION: vAc-Flag-CE-GP64 is useful for detecting the hepatitis C virus at early stages. 相似文献