邻水县农村产业系统模型决策方案

本文从众多方案中选出6个方案,作为邻水县1990、1995和2000年三个年段的系统模型决策方案,并对这些方案进行了多方面的分析,为系统规划设计和领导决策提供科学依据。     

Biflavonoids from Caper (Capparis spinosa L.) fruits and their effects in inhibiting NF-kappa B activation

Caper (Capparis spinosa L.) fruits have been widely used as food and folk medicine in the Mediterranean basin and in central and west Asia. In this study, two biflavonoids, isoginkgetin, and ginkgetin, together with three other flavonoids, were isolated from caper fruits. Their chemical structures were elucidated by spectroscopic analyses and comparison with literature. To our knowledge, isoginkgetin, ginkgetin and sakuranetin were identified in caper for the first time. Notably, it is also the first time that biflavonoids have ever been found in the Capparidaceae. Concentrations of the two biflavonoids were measured in caper fruits collected from four major growing areas in northwest China. The anti-inflammatory effects of the flavonoids from caper fruits were evaluated by secreted placental alkaline phosphatase (SEAP) reporter assay, which was designed to measure nuclear factor-kappa B (NF-κB) activation. Isoginkgetin and ginkgetin showed inhibitory effects in initial screen at 20 μM, while the effect of ginkgetin was much greater than that of isoginkgetin. In a dose-response experiment, the IC(50) value of ginkgetin was estimated at 7.5 μM, suggesting it could be a strong NF-κB inhibitor and worthy of study in vivo.     

我国甜菜育苗移栽机械的研究进展和发展趋势

甜菜育苗移栽是一项高产栽培技术,但我国的推广面积却仅有12%.育苗移栽机械只有与我国甜菜生产相适应,才能促使育苗移栽技术顺利大面积推广.为此,回顾了我国近30多a来所研制的甜菜育苗移栽机械(包括碎筛土机、床土配制机、墩土机和移栽机)的研究进展,详述了各自的结构形式、工作原理和技术参数,分析了工作特点和优缺点;针对我国甜菜育苗移栽机械未能推广应用的现状,分析了存在的问题,提出了相应的建议,并预测了未来的发展趋势.     

牛巨噬细胞天然抗性蛋白Ⅰ基因可变剪接体(NRAMPI-ISO)的克隆及在细胞和组织中的表达

巨噬细胞天然抗性蛋白1 (NRAMP1)可抑制结核分枝杆菌(Mycobacterium)和布氏杆菌(Brucella)等多种胞内寄生病原菌的感染,提高动物机体的抗病能力.本研究从秦川牛脾脏中克隆了NRA MP1基因的一种可变剪接体NRA MPI-ISO,序列分析表明,NRA MPI-ISO比NRAMP1多了第3个内含子,从而导致编码序列提前终止于第3个内含子,NRA MPI-ISO编码200个氨基酸.为了探索可变剪接体NRAMPI-ISO的表达情况,本研究分别构建了原核表达载体pET-41-NRA MPI-ISO和真核表达载体pEGFP-NRA MPI-ISO.原核表达载体pET-41 -NRA MPI-ISO可在不同浓度的IPTG诱导下在大肠杆菌BL21中高效表达.真核表达载体pEGFP-NRA MPI-ISO转染牛成纤维细胞后,EGFP-NRAMP 1-ISO融合蛋白分布在细胞核和细胞质中,而正常的NRAMP1蛋白只分布在细胞质的溶酶体膜周围.半定量RT-PCR检测表明,NRA MPI-ISO基因在心、脾脏、肺脏等组织有较高的表达,而在脑、胰、生殖嵴中的表达量相对较低.本研究为进一步研究NRA MPI-ISO基因生物学功能提供了重要信息.     

Effects of chlorantraniliprole on development and reproduction of beet armyworm, <Emphasis Type="Italic">Spodoptera exigua</Emphasis> (Hübner)

The lethal and sublethal effects of chlorantraniliprole against Spodoptera exigua (Hübner) were evaluated under laboratory conditions by oral exposure of neonate larvae to the compound. The 72 h LC₅₀ value of this insecticide to S. exigua was found to be 12.747 μg l⁻¹. A progressive larval mortality of 24.32% for LC₃₀ treatment and 42.61% for LC₅₀ treatment was observed from 4th to 6th day after exposure, which resulted in the reduced pupation rates in exposure groups. The sublethal effects of this chemical were indicated by prolongation of larval period, the increase of pupal weight and decrease in hatch rate of egg. Chlorantraniliprole at LC₃₀ and LC₅₀ rate significantly delayed larval development; the developmental duration of surviving larvae was extended for 22.5 and 28.6%, respectively, compared with that of control group. LC₃₀ treatment increased the mean weight of pupa and induced to the production of heavier pupa (>150 mg). In LC₅₀ treatment, heavier pupa also showed up but the mean weight of pupa was not influenced. The egg hatch rate in LC₅₀ group was significant lower than that in control and LC₃₀ groups. No significant differences in pupal duration, emergence rate, sex ratio, egg number per female, and longevity of adults were observed among treatments. Chlorantraniliprole had exceptional activity against S. exigua according to concentration–response bioassay in laboratory, and the toxicities were primarily resulted from immediate lethality.     

重组M蛋白间接ELISA检测猪繁殖与呼吸综合征病毒抗体

用纯化的猪繁殖与呼吸综合征病毒重组M蛋白作包被抗原,建立了检测猪繁殖与呼吸综合征病毒抗体的间接ELISA方法,并确立了ELISA最佳工作条件:抗原包被浓度为3.5μg/mL,37℃1h加4℃过夜,血清(1:40)和酶标SPA(1:80)分别在37℃温育1h,加底物溶液常温显色5min。经重复性试验、交叉试验、阻断试验等试验结果表明该方法重复性好、特异性强、敏感度高;与美国IDEXX公司试剂盒相比较,特异性和敏感性分别为96.3%和93.5%,无显著性差异。用建立的方法检测临床血清样品168份,总阳性率为39.9%。     

Synthesis,fungicidal activity,and 3D-QSAR of pyridazinone-substituted 1,3,4-oxadiazoles and 1,3,4-thiadiazoles

A series of novel 5-[1-aryl-1,4-dihydro-6-methylpyridazin-4-one-3-yl] -2-arylamino-1,3,4-oxadiazoles, fungicidally active, were synthesized based on bioisosterism and tested in vivo against wheat leaf rust, Puccinia recondita. These compounds were shown to be fungicidally active, and their activity was influenced by the nature of the substituents. By using the three-dimensional quantitative structure-activity relationships (3D-QSAR) method of comparative molecular field analysis (CoMFA), we have studied the structure and activity relationship of the compounds containing both pyridazinone-substituted 1,3,4-thiadiazoles and pyridazinone-substituted 1,3,4-oxadiazoles. The 3D-QSAR modes gave good correlation between the variations on percent inhibition and the steric-electrostatic properties. The results are consistent with a common mode of action for the pyridazinone-substituted 1,3,4-thiadiazoles and the pyridazinone-substituted 1,3,4-oxadiazoles, which further confirms that the 1,3,4-oxadiazole ring is a bioisosteric analogue of the 1,3,4-thiadiazole ring. These offer important structural insights into designing highly active compounds prior to their synthesis.     

珠江流域1960―2012年降雨侵蚀力时空变化特征

降雨侵蚀力反映了降雨对土壤侵蚀的潜在能力,研究其时空变化特征对流域土壤侵蚀监测、评估、预报和治理等工作具有重要意义。根据珠江流域43个气象站1960-2012年逐日降雨资料计算各站点降雨侵蚀力,采用线性回归,Mann-Kendall方法,小波分析和Kriging插值等方法对流域降雨侵蚀力进行了时空变化分析。结果表明:珠江流域多年平均降雨侵蚀力值的分布范围为1 858.0~14 656.6 MJ·mm/(hm2·h),平均值为7 177.1 MJ·mm/(hm2·h),与多年平均降雨量极显著相关(相关系数0.952,P0.01),空间分布规律与多年平均降雨基本一致,即总体上均呈从东到西逐渐递减的规律,被统计站点的降雨侵蚀力随着经度增加而增加,但随纬度增加而减少;流域年、季节、汛期和非汛期降雨侵蚀力变化趋势均不显著,均没有发生显著的突变,其中春、秋两季降雨侵蚀力呈下降趋势,其余时间段呈上升趋势;珠江流域大部分地区年降雨侵蚀力呈上升的趋势,其中韶关站点上升显著,沾益站、风山站、河池站、百色站、柳州站、融安站和桂林站的冬季降雨侵蚀力同样上升显著,这些地区面临的水土保持压力较大;流域年均降雨侵蚀力变化主周期为3.8 a,且存在2.0~7.0 a的振荡周期。研究结果可为珠江流域的水土保持、农业和生态保护,灾害控制等工作提供科学决策依据。     

Stages in the History of China's Acid Rain Control Strategy in the Light of China-Japan Relations

We analyze the history of acid rain in China over the last three decades in the light of the relationship between China and Japan. China has been aware of the problem of acid rain and has been conducting scientific research since the late 1970s. However, little effort has been put into practical countermeasures. In the early 1990s, acid rain was re-evaluated as an international environmental problem. Meanwhile, Japan became concerned about trans-boundary air pollution from China. What is important is that Japan's concern strongly influences China's acid rain policy. In the context of growing international concern for environmental problems, China has taken remarkable steps to control acid rain. In this respect, dealing with acid rain is an issue of national pride for China.     

Monitoring lipase-catalyzed interesterification for bulky fat modification with FT-IR/NIR spectroscopy

This work demonstrates the application of FT-IR and FT-NIR spectroscopy to monitor the enzymatic interesterification process for bulky fat modification. The reaction was conducted between palm stearin and coconut oil (70:30, w/w) with the catalysis of Lipozyme TL IM at 70 degrees C in a batch reactor. The blends and interesterified fat samples in liquid form were measured by attenuated total reflectance based FT-IR (spectra region, 1516-781 cm(-1)) and transmission mode based FT-NIR (spectra region, 5369-4752 cm(-1)) with the temperature of both controlled at 70 degrees C. The samples in solid form were also measured by reflectance-based FT-NIR (spectra regions, 7037-6039 and 5995-5612 cm(-1)) at room temperature. Calibrations of FT-IR and FT-NIR for conversion degrees (evaluated by triglyceride profile), solid fat contents (SFC), and dropping points of interesterified products were carried out by using partial least-squares regression. High correlations (r > 0.96) were obtained from cross validations of the data estimated by FT-IR, FT-NIR, and the above-mentioned conventional analytical methods, except for correlations (r = 0.90-0.95) between FT-IR and SFC profiles. Overall, FT-NIR spectroscopy coupled with transmission mode measured at 70 degrees C had the highest correlations, which also had the closest conditions to the sampled products in the process, indicating a great potential for implementation as an on-line control for monitoring the enzymatic interesterification process.