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    Since the onset of human societies, settlement patterns and social structures have been shaped by access to water. This review covers historical and recent examples from Cambodia, Central Asia, India, Latin America and the Arabian Peninsula to analyze the role of water resources in determining the rise and collapse of civilizations. Over recent decades increasing globalization and concomitant possibilities to externalize water needs as have obscured global dependence on water resources via telecoupling, but rapid urbanization brings it now back to the political agenda. It is foremost in the urban arena of poorer countries where competing claims for water increasingly lead to scale-transcendent conflicts about ecosystem services. Solutions to the dilemma will require broad stakeholder-based agreements on water use taking into account the available data on water resources, their current and potential use efficiency, recycling of water after effective treatment, and social-ecological approaches of improved governance and conflict resolution.

    Article 2021-04-30

    COMPARISON OF POMELO (

    Pomelo is a member of the genus that is a key contributor to the breeding of modern citrus cultivars. China is the largest producer of pomelo and one of the top five pomelo exporting countries. Pomelos from Thailand are also well-known for their excellent quality and flavor and are ranked in the top ten export countries. This review introduces pomelo planting locations and conditions in China and Thailand. The characteristics and qualities of some commercial pomelo cultivars in China and Thailand are summarized to introduce them to international consumers and to document their similarities and dissimilarities. Data on bioactive compounds and antioxidant capacity are also included for most Chinese and Thai pomelos to highlight how they differ in this aspect because consumers are increasingly interested in healthier foods. In addition, the sensory perception in terms of aroma, flavor, texture and taste attributes, consumer perspective and preferences are discussed.

    It has previously been shown that tryptophan, the biosynthesis precursor of alkaloids, and its derivatives have anti-TMV activity both and . Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of L-tryptophan with triphosgene to produce L-tryptophan- -carboxylic anhydride, which then reacts with -octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a > 40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.

    Wentao XU ,   Hao TIAN   et al.
    Intensive agriculture in China over recent decades has successfully realized food security but at the expense of negative environmental impacts. Achieving green transformation of agriculture in China requires fundamental restructuring of cropping systems. This paper presents a theoretical framework of theory, approaches and implementation of crop diversification schemes in China. Initially, crop diversification schemes require identifying multiple objectives by simultaneously considering natural resources, limiting factors/constraints, and social and economic demands of different stakeholders. Then, it is necessary to optimize existing and/or design novel cropping systems based upon farming practices and ecological principles, and to strengthen targeted ecosystem services to achieve the identified objectives. Next, the resulting diversified cropping systems need to be evaluated and examined by employing experimental and modeling approaches. Finally, a strategic plan, as presented in this paper, is needed for implementing an optimized crop diversification in China based upon regional characteristics with the concurrent objectives of safe, nutritious food production and environmental protection. The North China Plain is used as an example to illustrate the strategic plan to optimize and design diversified cropping systems. The implementation of crop diversification in China will set an example for other countries undergoing agricultural transition, and contribute to global sustainable development.

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