新合院生活的景观体验——黄骅新城家园景观设计     

褚天骄  赵文斌  陆潇潇 《农业科技与信息》2010,(3)

文章从分析现状入手,依据建筑规划所形成的空间提出了新合院的景观设计理念,并通过对道路系统、出入口、水系、植物、老年儿童活动空间等景观空间的精心组织,形成小区一心、二街、三轴、四院的景观骨架,再结合对景、框景等造园手法来打造一个简洁朴实又不失特色的小区景观。  相似文献   

农业机械手钳的人机安全设计     

楚杰 《农机化研究》2010,32(3)

分析了应用较为普遍的农业机械工具—农业手钳的人机安全学设计因素,并通过实验计算得出以人机工程学为基础的手钳的参数设计。主要从人机工程学的角度出发,通过分析手钳在使用时的舒适度和把手尺寸,以评估设计的合理性。同时,分别针对男女群体正态分布的第5百分位、第5 0百分位和第9 5百分位的测量数据进行手柄设计和尺寸评估,得出农业机械手钳的科学合理性尺寸设计。  相似文献   

Establishment of Efficient Regeneration System of Populus×euramericana cl.‘Bofeng’     

Cui Xudong  Su Xiaohua  Zhang Bingyu  Chu Yanguang  Huang Qinjun  Zhang Weixi  Liu Boyang 《中国林业科技(英文版)》2012,(3):54-55

Compared with the species of Leuce section,the difficulty in plant regeneration during tissue culture for the species of Aigeiros section is a key limiting factor for their application in genetic engineering of forest trees.In this study,the plant growth regulators combination,copper concentration,light intensity,and the selection pressures of kanamycin were investigated using leaves of Populus×euramericana cl.’Bofeng’ as explants,and a stable and high efficient regeneration system was established.Using this system,both the shoot regeneration rate and rooting rate were up to 100%,and the average number of differentiated shoots in each leaf explant was up to 20,and the survival rate of seedlings reached 98%.The optimal selection pressure of kanamycin in shoot inducement for leaf-explant was 40 mg·L^-1,and the optimal selection pressure of kanamycin in root inducement of adventitious bud was 20 mg·L^-1.The authors also found that differentiation rate of adventitious buds of P.×euramericana cl.’Bofeng’ could be significantly promoted by increased copper concentration,and this is the first report about the key role of copper（Cu） in explant regeneration of Poplars.This regeneration system with high frequency which was established by the authors was as good as that of species of Leuce section,and it provides a good technological platform for genetic engineering of forest tree which uses the species of Aigeiros section as model materials.  相似文献   

西洋参韧皮坏死病与类菌原体     

逯弘捷  孟光  刘亚杰  初振仁  李北辰  史淑琴  朱平 《植物病理学报》1988,18(2):85-88

 西洋参(Panax quinquefolium)罹病表现为花变叶和韧皮坏死症状.根部韧皮组织超薄切片观察,发现大量具单位膜而无细胞壁,形态各异的类菌原体。存在于筛管分子及其周围伴胞中.类菌原体大小为90—950nm,外膜厚度8—9nm.以50单位/ml四环素三次喷洒植株地上部,能显著降低根部块死的病情指数.初步认为西洋参韧皮组织坏死,是由类菌原体引起的病害。  相似文献   

水稻品种苗期阶段对白叶枯病的抗性研究   总被引：1，自引：0，他引：1  

褚菊征 Miw  T.W. 《植物病理学报》1990,20(4):281-286

 根据水稻品种各叶期对白叶枯病的抗性表现和强弱程度可分为四类:(1)全期抗病型;(2)全期中抗型;(3)苗感成株抗病型;和(4)全期感病型。可以看出,水稻品种除少数苗感成抗型外,其余三种抗性类型苗期与成株期的抗性反应是一致的。由于中抗、成抗和感病品种各叶期的抗性有随着叶位的升高而抗性增强的趋势,不同抗性品种在苗期阶段抗感对比均较成株期明显。因此,水稻品种对白叶枯病的抗性鉴定采用苗期鉴定方法是可行的。影响水稻品种苗期抗性的因素是:苗龄(叶期)、观察时期、品种与菌株的组合等。  相似文献   

甘肃省干旱半干旱地区降水的研究   总被引：1，自引：1，他引：1  

谭启后  褚友余 《干旱区资源与环境》1991,5(2):50-59

本文通过对甘肃省降水资料的具体分析,指出了在干旱、半干旱地区降水的主要特征,如暴雨的特殊性、固体降水与海拔关系、降水量与海拔关系、降水量与作物产量关系等,并对如何提高降水利用率,发展农业生产等问题进行了探讨。  相似文献   

拟垫跗螋生物学特性的研究     

王宗典  帅先福  龚秧初  王大智  王浩毅  周文豹 《中国生物防治》1994,(2)

拟垫跗螋是为害造纸原料荻和芦的害虫（蚜虫、蓟马、螨等）的重要捕食性天敌。在湖南洞庭湖区一年发生２代，以成虫和若虫在残杆、渣叶和土缝中越冬。成虫寿命第１代约４个月，第２代连越冬达１０个月。雌雄性比约５４。雌雄均可多次交尾，有的雌虫产卵后又可交尾。每头雌虫的产卵量平均３９．３粒。卵期平均６．５天。若虫期第１代近４个月，第２代连越冬约９个月。大田消长主要受地势高低、洪水、农药、食物等因素影响。并对保护利用跗螋控制害虫的措施进行了讨论  相似文献   

The effect of cyclopiazonic acid on the development of pale, soft, and exudative pork from pigs of defined malignant hyperthermia genotype     

Byrem TM  Booren AM  Hill GM  Chu FS  Strasburg GM 《Journal of animal science》1999,77(1):166-172

Malignant hyperthermia (MH) and the mycotoxin cyclopiazonic acid (CPA) are each associated with abnormal calcium homeostasis in skeletal muscle, a key underlying factor in the development of pale, soft, and exudative (PSE) pork. To determine whether the natural presence of CPA in livestock feed ingredients contributes to the varying incidence of PSE in the pork industry, various levels of CPA (.1 to 50 mg/kg of diet) were included in the diets of market weight hogs (n = 52) of defined malignant hyperthermia genotype (NN = normal, Nn = a MH carrier, and nn = MH-positive). Animals with two copies of the MH mutation (nn) displayed improved live animal performance compared with NN and Nn animals (increased feed intake, average daily gain, and feed efficiency) but yielded lower quality loin chops as indicated by lower 45-min pH (P<.01), higher Commission Internationale de l'Eclairage (CIE) L* color coordinate values (P<.05), and higher drip losses (P<.01). The effects of CPA varied. In the first feeding trial, conducted under normal outside temperatures (2 degrees C), CPA had no effect (P> .2) on either live animal performance or meat quality. During the second trial, conducted under extreme outside temperatures (-18 degrees C), CPA-dependent reductions (P<.05) in feed intake, average daily gain, and 45-min pH in nn hogs support the possibility of interactions between malignant hyperthermia and dietary CPA on skeletal muscle calcium homeostasis and the development of PSE pork. These results suggest that this interaction may require stressful environmental conditions or the ingestion of CPA doses much higher than occur under natural conditions.  相似文献   

北京栽培白蘑菇病害的研究   总被引：3，自引：0，他引：3  

朱慧贞 《植物病理学报》1982,12(3):54-58

 1979~1980年进行箱式栽培白蘑菇的试验,并同时调查对比病害发生情况,和采用各种措施的效果。  相似文献   

Recombinant equine growth hormone administration: effects on synovial fluid biomarkers and cartilage metabolism in horses     

Dart AJ  Little CB  Hughes CE  Chu O  Dowling BA  Hodgson DR  Rose RJ  Johnson KA 《Equine veterinary journal》2003,35(3):302-307

REASONS FOR PERFORMING STUDY: Recombinant equine growth hormone (reGH) has recently been evaluated for effects on body condition and wound healing. It has the potential to influence articular cartilage via stimulation of IGF-1. OBJECTIVES: To investigate effects of administration on synovial joint metabolism. METHODS: Six mature horses were given 20 microg/kg bwt reGH daily for 8 weeks by i.m. injection. Three control horses were injected with sterile water. Serum and synovial fluid samples were collected at 6, 8, 11 and 16 weeks for GH and IGF-1 assays. Articular cartilage harvested at week 16 was evaluated by Western analysis using monoclonal antibodies BC-13, BC-4, 8-A-4 and CH-3. RESULTS: Concentrations of IGF-1 in serum and synovial fluid were significantly elevated (P < 0.05) at 6 and 8 weeks in the reGH group. Glycosaminoglycan concentrations in synovial fluid were significantly less than controls at these time points, suggesting that reGH may modulate proteoglycan metabolism in articular cartilage. In the reGH group, there were not any alterations in synovial fluid content of 3B3(-) epitope or aggrecan metabolite, or in aggrecan or link protein catabolites retained within cartilage, that might be expected with development of osteoarthritis. CONCLUSIONS: Intramuscular administration of reGH may be a more efficient means of delivery of IGF-1 to joints for cartilage resurfacing initiatives. POTENTIAL RELEVANCE: We found no alterations in cartilage metabolism indicative of development of osteoarthritis.  相似文献