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61.
This study characterized farmer users and nonusers of mass media as channels of agricultural information. A structured interview was used to obtain data from 316 randomly selected farmers in Benue State, Nigeria. The data were subjected to discriminant analysis and the following socioeconomic characteristics significantly differed at a 5% level of probability between users and nonusers of mass media (and their F-ratio values): education (6.30), income (5.12), gender (4.84), and socioeconomic status (4.83). Farmer users of mass media are therefore those who have good level of education, belong to a relatively high income bracket, and are typically male and of a relatively high socioeconomic status. Farmers’ socioeconomic characteristics should be considered in planning mass media usage in agricultural information dissemination.  相似文献   
62.
对发酵工程实验课进行改革,以提高学生在实验课中的主体地位。  相似文献   
63.
钱达 《北方园艺》2012,(3):82-85
通过对欧美和日本等国景观规划控制的总结和我国景观规划控制现状的分析,促使在借鉴他国先进经验的基础上,结合我国实际情况,提出相应的手段与方法以提升我国景观规划控制水平,并展望新的目标,以有效保护和构建有特色的城市形象。  相似文献   
64.
黄婷  刘俭 《江西农业学报》2013,(12):148-150
总结了宁夏农民专业合作组织的发展现状,并从农民专业合作组织对宁夏农产品的质量保证、品牌创新、市场拓展等方面论述了农民专业合作组织对宁夏农产品品牌推广的促进作用。  相似文献   
65.
以‘鸭梨’为材料,用RT-PCR及RACE技术克隆CaM,并借助实时定量PCR技术分析‘鸭梨’花、叶及果实不同发育时期的表达模式,获得了2个长度为764和801bp的CaM cDNA序列,分别命名为PbCaM1和PbCaM2,二者均含有450bp完整开放阅读框,编码149个氨基酸,且氨基酸序列相同。‘鸭梨’CaM在系统进化上具有高度保守性,与苹果相比,两者氨基酸序列为100%一致性。PbCaM1和PbCaM2具有时空表达特异性,它们在成叶、盛花期花瓣和幼果期表达量较高。本研究表明CaM具有高度保守性,PbCaM1和PbCaM2在‘鸭梨’果实早期生长发育过程中起着非常重要的作用。  相似文献   
66.
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   
67.
农民工随迁子女教育问题是当前一个亟待解决的社会难题。由于国家实施"两为主"政策,致使流入地政府承受着巨大的财政压力,在解决农民工随迁子女教育问题上心有余而力不足。而近年来引进的"教育券"制度,在实际工作中也存在一定的局限性。基于由国家、流出地政府、流入地政府按一定比例共同承担农民工随迁子女义务教育经费的理论,提出的"教育卡"新构想,则可以从操作层面较好地解决教育经费承担的一系列问题。  相似文献   
68.
通过对某专业院校图书馆文献借阅情况调查,就改进院校图书馆管理,优化读者服务谈了一些看法。侧重于研究教学型的专业院校图书馆作讨论。  相似文献   
69.
The social background, farm characteristics, indicators of income and self-evaluation returns of 96 randomly selected users of a Basic Animal Health Service (BAHS) programme in northern Malawi were compared with those of 96 matched past-users and 96 non-users, respectively. All 288 farms were visited between July and October 1997. Data analysis was performed using univariate and multivariate techniques. The results showed that, on average, BAHS users had larger cattle herds (16.3) than part-users (14.7) or non-users (12.4). Similarly, the annual yields of crops were higher for users compared to either of the other groups. Users occupied better houses and owned a larger number of farm and household items than did part-users or non-users. A third of all farmers were engaged in additional income generation to lessen the risk of poverty. However, analysis of the livestock management and the educational background of the farmers suggested that usage of the BAHS programme was not only determined by already existing `wealth'. Improved livestock husbandry and management measures, which do not require capital investment, were more frequently applied by users compared to either of the other groups. Non-users and part-users had attained a lower level of education, were less open towards improved farming methods and felt less knowledgeable than BAHS users. The average straight-line distances from farms using BAHS to their respective village animal health worker (2.2 km) or veterinary assistant (2.9 km) were similar but varied according to ecological zone. Intensified extension and awareness meetings in villages will be required to get more non-users involved in BAHS.  相似文献   
70.
国外土地整理实践对我国土地整理的启示   总被引:1,自引:0,他引:1  
土地整理在我国起步较晚,很多理论还不成熟。采用文献参阅法,从土地整理的发展阶段、内容和特点等方面介绍了德国、俄国和荷兰等国外土地整理的基本情况,并由此得出其对我国土地整理的启示:建立健全土地整理法律政策,重视土地整理的权属调整,拓宽土地整理融资渠道,重视土地整理中的生态环境保护,积极推动土地整理公众参与和高度重视土地整理规划等。  相似文献   
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