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1.
A survey was conducted in eight secondary schools located in two watersheds in Gujarat and Rajasthan (semi-arid region of India) to assess students’ perceptions about groundwater scarcity issues and the impact of the scarcity on their educational opportunities. Survey responses to a detailed questionnaire by a cohort of students in both watersheds; school attendance records of year 8 class students (13–14 years old) and responses gathered via a socio-economic survey involving 500 families in the study area were used in the study. In both watersheds, >90% students identified groundwater scarcity as a major issue. Required to work at home or farm, about 65% students in Gujarat and 60% in Rajasthan missed school for up to 2 days/month; and a smaller proportion (~ 30%) missed schools for 4 or more days/month. School absenteeism was found to be linked with gender; female students missed schools more frequently than their male counterpart. The school attendance records in Rajasthan showed that the frequency of female students missing schools for 5 or more days/month was on an average 2–10 times greater than that for males. The gender difference in absenteeism in all schools was statistically significant (P?<?.018**). The study highlighted that groundwater scarcity in the study area, and consequent demand on their time for household work including fetching drinking water are contributing factors towards limiting their educational and economic opportunities. Groundwater scarcity can be one of the key factors that can limit inclusiveness and empowerment of women and need to be considered in policy-making.  相似文献   
2.
The roots of most land plants establish intimate associations with soil fungi. This association of plant roots with fungi is termed mycorrhiza. It is a marriage between two highly dissimilar organisms based on mutual exchange of nutrients: while the plants provide photosynthetically made carbon compounds to the fungi, the fungi in turn provide to the plants nitrogen and phosphorus scavenged from the breakdown of organic polymers in natural substrates. This mutually beneficial partnership makes possible the green cover on Earth and of all life, ultimately, dependent on plants.  相似文献   
3.
Purpose: The aim of this article to examine key irrigation management issues and their implications for future research and extension developments.

Design/Methodology/Approach: Peri-urban landscapes are important as they supply fresh fruit, vegetables, turf, ornamental plants and other farm products to the cities. In this study, the Hawkesbury–Nepean Catchment (HNC) was used as a case study and a number of farmers were selected to examine how they use the available technologies for irrigation scheduling to make better decisions for developing water management strategies on their farms. The farmers who participated in the study were mainly growing fruit, turf, vegetables, pasture, olive trees and cut flowers.

Findings: It was observed that a range of factors influenced correct irrigation scheduling decisions of farmers, including their limited understanding of the soil-water-plant relationship, costs of implementing soil-moisture monitoring technology and finding a date for irrigation activity that is compatible with their other farm tasks. It was also found that the farmers’ experiential knowledge played an important role in their irrigation scheduling decisions. The study indicated that irrigation scheduling approaches, which have a low labour requirement and are cost effective and easy to use would be helpful to farmers.

Practical Implications: The study highlighted that there are some irrigation management issues for research and extension that are specific to peri-urban farming and as such they need to be addressed to improve irrigation management and to cope with future water scarcity in urban and peri-urban landscapes.

Originality/Value: This is one of few studies that examine irrigation scheduling issues in a peri-urban context. The study has revealed that irrigation scheduling in reality cannot be an exact science, but it needs to accommodate various farmer constraints in field situations and may have implication for extension activities in peri-urban and other regions.  相似文献   

4.
The water-repellent surface of lotus (Nelumbo nucifera) leaf and flower is due to nanosized wax papillae on the upper side of each epidermal cell. As a result, raindrops make a high contact angle with the papillae and roll off carrying dust and dirt particles, leaving the surface clean. This self-cleaning property of highly hydrophobic surfaces, termed as the lotus effect, has opened the possibilities of fabricating superhydrophobic surfaces for a variety of products.  相似文献   
5.
This essay reflects upon the themes that emerged from the seminar "Teaching and Organization of Studies in the Virtual and Classical University: Conflict and/or Mutual Reinforcement", for which the articles appearing in this issue of Higher Education in Europe were originally prepared. The reflections are organized around four major themes: (i) the acceleration of change in higher education owing mostly to the ICTs; (ii) complementarity and contrast between virtual and classical universities; (iii) institutional responses to change; and (iv) quality issues. Various agendas for further attention are proposed.  相似文献   
6.
Most plants are attached via their roots to specialized fungi. The filamentous hyphae of these fungi extend beyond the nutrient-depleted zone in the soil, absorbing and supplying nutrients to the plants in exchange for photosynthetically-made carbon compounds manufactured by the plant. The hyphae also attach to litter and decompose the organic matter, releasing the mineral ions sequestered in the structural polymers. The mineral ions are absorbed and translocated to the roots. Most plants are so dependent on their fungal partners for supplying nutrients that they languish or die without them. Our understanding of this fascinating interaction, to a large extent, has come from the pioneering work of Sir David J Read, FRS, Emeritus Professor of Plant Sciences at the University of Sheffield, UK. Ramesh Maheshwari is a former Professor and Chairman of the Department of Biochemistry, Indian Institute of Science, Banglaore. This is his sixth article for Resonance.  相似文献   
7.
Amazing microorganisms thrive at high temperatures incompatible with the familiar forms of life. A few species from hot springs or from the vicinity of hydrothermal vents at the floor of the oceans are the basis of a multimillion dollar industry. An entirely new form of animal life has been discovered around the volcanic eruptions from the sea floor. This animal life thrives in the permanently dark environment only because it harbors symbiotic bacteria that synthesize food molecules from inorganic chemicals in the emissions. Thermophilic microorganisms are involved in composting and humification in terrestrial habitats.  相似文献   
8.
9.
The objective of the present study was to evaluate hypolipidemic effect of methanolic extract of Celastrus paniculatus in experimentally induced hypercholesterolemic rats. Hypercholesterolemia was induced by feeding the animals with high fat diet. Oral administration of methanolic seed extract (50%) of Celastrus paniculatus at the optimized dose of 65 mg/kg body weight, substantially reduced the plasma total cholesterol, triglycerides and LDL cholesterol in comparison with induced hypercholesterolemic animal group and the results were comparable with the standard hypocholesterolemic drug and almost similar to the control group. Atherogenic index and liver weight of treated animals also showed significant decrease compared to the hypercholesterolemic animals. It substantially increased the HDL cholesterol level as compared to control group. A significant increase in the activities of lipoprotein lipase and plasma LCAT enhanced hepatic bile acid synthesis and thereby, increased degradation of cholesterol to neutral sterols. Furthermore, the activities of HMG-CoA reductase, glucose 6-phosphate dehydrogenase and malate dehydrogenase were significantly reduced. Histological studies showed less cholesterol deposits in the aorta of animals fed with seed extract of C. paniculatus compared to the induced hypercholesterolemic animals not given C. paniculatus supplement.  相似文献   
10.
评定复杂协调性项目运动员能力的理论依据和测试选择   总被引:1,自引:0,他引:1  
专项运动员协调能力始终是竞技后备人才培养问题的焦点。为了确定协调能力与技/战术能力、调整能力发展水平、青少年运动员和成年运动员心理/生理功能发育之间的相互关系,评定复杂协调性项目运动员能力,利用测试作业对训练过程各个阶段中协调能力的发展动态进行跟踪,比较这些结果,同时对各个运动项目运动员的协调训练程度进行比较分析。测试结果有助于了解青少年运动员协调训练程度的基本概貌,编制针对具体基础性协调能力发展水平的分辨性评定的标尺,同时确定协调训练程度总的水平。结果显示:协调能力作为制约比赛活动效果的因素之一,其意义越来越重要,从而决定了开展针对研制诊断协调训练程度计划的研究的必要性。作为测试作业的基础应当是有科学依据的理论,它不仅使监督性测试具有心理/生理学含义,而且能揭示某一种协调能力发展中存在的个体差异的本质。  相似文献   
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