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541.
This article discusses the insufficient consideration of the role of state practice in the interpretation and implementation of Article 121(3) of the UNCLOS by the Arbitral Tribunal in the South China Sea Arbitration Case. The article argues that the Tribunal's view on the “threshold” established and its conclusion that there was no evidence that an agreement existed based upon state practice on the interpretation of Article 121(3) are open to question.  相似文献   
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介绍“半自助式”教学模式提出的背景、涵义和研究理念,明晰该模式的实施方案和考核评分体系.以《生物工艺学》课程的教学组织为典型案例,分四个阶段介绍如何通过实践题目的布置引出课程内容体系,如何安排基础知识学习,如何将基础知识应用于具体生物工程产品生产以及如何做生产工艺的工厂设计,分析成效,以期为生物工程类课程教学提供一种新型教学模式,提高学生工程实践能力.  相似文献   
543.
The purpose of this study was to measure both summer and winter nutrient mitigation efficiencies of three aquatic plants found in agricultural drainage ditches in the lower Mississippi River Basin. Mesocosms (1.25 × 0.6 × 0.8 m) were filled with sediment and planted with monocultures of one of three obligate wetland plant species, Typha latifolia, Thalia dealbata, and Sagittaria latifolia, or left nonvegetated to serve as controls. Mesocosms were amended with nitrate, ammonium, and phosphate over a 4-h hydraulic retention time, followed by an 8-h flushing with nonamended water to assess residual nutrient leaching in both summer and winter exposures. Significant interactions between vegetation type and season were noted for both nitrate and total inorganic phosphorus concentrations and loads. Future research will focus on altering hydraulic retention time for improved efficiency, as well as the specific contribution of microbial activity to nutrient mitigation.  相似文献   
544.
There are very few studies on Tuber melanosporum associated with Cistus populations. In central Spain, we confirm that C. laurifolius shows carpophore production of Tuber melanosporum. This study demonstrates a correlation between T. melanosporum production and the size of the 41 burns, with burn size explaining 26 % of the variability in carpophore production. However, statistical analysis of the results indicates that average production of 21 burns with Cistus laurifolius is 73 % lower than the production of 20 burns associated with Quercus/Corylus without Cistus laurifolius in this zone, respectively. C. laurifolius develops small burns, which has an impact on their carpophore production, and their soils have 92 % less active carbonate than the burns associated with Quercus/Corylus in this zone, respectively. The low levels of active carbonate allow Cistus laurifolius to grow, but impair Tuber melanosporum production. We thus provide a mechanism, based on the inability of Cistus laurifolius to grow in highly carbonated soils, which contradicts the well-known fact that C. laurifolius might act as a transmitter of Tuber melanosporum mycorrhizae. These results indicate that this rockrose can not be considered a useful species for truffle culture. We thus recommend that particular attention should be given to the concentration of active carbonate present in the soil in future studies on the relationship between Cistus species and truffles.  相似文献   
545.
Temporal organization in phototactic rhythm in male Clarias batrachus was studied in a choice chamber consisting of a photic zone and an aphotic zone. Results indicate that most of the fishes exhibited a statistically significant 24-h variation in the frequency of visits to the photic zone with a peak frequency at late night or early morning. Cosinor analysis of phototactic index (PI) values also yielded comparable results. This behaviour of C. batrachus shows similarity with its other activities, like air gulping, surfacing, foraging or predation that occur chiefly at night. The light intensity at the surface of a natural water body is more than at the bottom, even at night. Therefore, the peak phototactic activity observed in C. batrachus in the night or early morning could be attributed to its daily migration from the bottom to the surface of the water bodies. The results of the present study might be useful in aquaculture practice and inland fishing.  相似文献   
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Instructors can deliberately design for equity, diversity, and inclusion, including for large first‐year classes, and now instructors have added challenges given COVID‐19. Our paper explores the question: How do we integrate equity, diversity, and inclusion and universal design for learning (UDL) into first‐year, undergraduate ecology and evolution introductory lessons given the COVID‐19 pandemic? Given the large field exploring equity, diversity, and inclusion, we chose to focus on developing reflective practice question rubrics for before, during, and after lessons to encourage UDL for instructors, teaching assistants, and learners. We conducted a focus group within our team and discussed ideas related to online learning, including related pitfalls and solutions. Lastly, we created a figure to illustrate ideas and end with a general discussion. Our reflective practice questions for UDL rubrics, figure, focus group, and discussion aim to increase positive action for equity, diversity, and inclusion in the classroom and beyond.  相似文献   
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Plant and soil nematodes significandy impact our lives. Therefore, we must understand and manage these complex organisms so that we may continue to develop and sustain our food production systems, our natural resources, our environment, and our quality of life. This publication looks specifically at soil and plant nematology. First, the societal impact of nematodes and benefits of nematology research are briefly presented. Next, the opportunities facing nematology in the next decade are outlined, as well as the resources needed to address these priorities. The safety and sustainability of U.S. food and fiber production depends on public and administrative understanding of the importance of nematodes, the drastic effects of nematodes on many agricultural and horticultural crops, and the current research priorities of nematology.  相似文献   
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