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21.
Protected areas are recognized as an essential tool to safeguard habitat integrity and biodiversity in the Anthropocene. Substantial efforts have been made to clarify the conditions under which they deliver conservation outcomes effectively. Location, spatial design, management strategy and threats, have commonly been identified as key factors. The impacts of these factors have, however, often been evaluated independently, and there is limited information on how their combined and interactive effects can improve or hinder protected area effectiveness. Here we develop a framework for understanding the combined effects of these factors. This has important implications for how protected areas are established and maintained.  相似文献   
22.
目的:研究以问题为导向的互动式教学法在普外科临床教学中的应用。方法:选取2010级应用以问题为导向的互动式教学法的普外科学生120名(研究组),另选取2009级之前的传统教学法普外科学生120名(对照组),分析两组的成绩,对学生进行问卷调查,了解学生对两种教学的评价。结果:研究组平均分为(79.8±2.3)分,高于对照组的(77.6±2.1)分,两组比较差异无统计学意义(P0.05);研究组分数≥80分者显著多于对照组,两组比较差异具有统计学意义(P0.05);研究组学生对授课的满意度显著高于对照组,两组比较差异具有统计学意义(P0.05)。结论:以问题为导向的互动式教学法应用于普外科临床教学中具有较好的效果,能提高学生的分数,提高学生的满意度。  相似文献   
23.
In West Africa, policies for prescribed early fire, grazing and selective tree cutting in the savanna-woodlands are rarely based on long-term experimental studies. The purpose of this study was to provide scientific evidence based on field data from two case studies for an informed discussion on the long-term response of herbaceous abundance both at the community and individual species levels to fire, grazing, selective cutting and their interactions. A long-term factorial experiment was established in two State forest reserves in Burkina Faso that mainly differ in their soil attributes. Community abundance data recorded from line intercept sampling over 13 years were analyzed using a multivariate ordination technique known as principal response curves (PRC).  相似文献   
24.
The twentieth century witnessed a dramatic increase in the useof statistics by biologists, including systematists. The modern synthesis and new systematics stimulated thisdevelopment, particularly after World War II. The rise of ``thestatistical frame of mind' resulted in a rethinking of relationship between biological and mathematical points of theview, the roles of objectivity and subjectivity in systematicresearch, the implications of new computing technologies, and theplace of systematics among the biological disciplines.  相似文献   
25.
Interactive playback experiments were used to study the signal value of alternating and overlapping singing in the Yellowhammer Emberiza citrinella. We carried out interactive playback experiments in which 13 males were subjects of two treatments that differed in temporal pattern of playback song delivery (alternating vs overlapping). We measured 12 parameters of males' response, belonging to three categories: song output, call output and mobility (distance from loudspeaker and flights). The results do not confirm the hypothesis that the overlapping pattern is a signal of stronger threat, as compared to the alternating pattern. Overlapping and alternating playbacks generally elicited a similar response, characteristic for highly aroused males. The only significant difference found concerned latency of approach to the loudspeaker during the playback stage. When playback alternated with songs of males, the birds gained higher scores on the axis of that response measure. Such a result was linked to differences in how the alternating and overlapping playbacks affect detection and localisation of simulated rivals, rather than to the signal's threat value itself. The strong response of Yellowhammer males is consistent with the high intrusion rate and possibility of extra-pair copulation in this species, which probably simplifies close-range communication towards more aggressive and unequivocal repelling of rivals irrespective of the temporal patterning of song.  相似文献   
26.
Education and research in the discipline of microbiology is set for change as a result of computers being used as teaching and learning tools. In order to catalyse this change in Nigeria, previous computer experience, knowledge and attitude to computers of Nigerian microbiology students and professionals was determined. Our results indicate the need to increase the awareness of use and potentials of computers in microbiological research and education.  相似文献   
27.
Synopsis Quantification of fish school structure is difficult because of: (1) the large amount of positional data that must be recorded, (2) the fact that schools are moving, and (3) the fact that schools are threedimensional. Computer tools for addressing these problems include x,y digitizing devices interfaced to computers and interactive computer graphics systems. General computer algorithms now exist for 3-D reconstruction of schools given any two 2-D views such as photographs.Our computerized film analyzer, the Galatea system, is described in detail. This system allows for rapid, accurate input of multiple points which can be followed through each frame in a film sequence. Its software packages perform 3-D reconstructions, analyze undulatory motion, and do extensive statistical tests.  相似文献   
28.
The emerging field of synthetic biology has the potential to improve global health. For example, synthetic biology could contribute to efforts at vaccine development in a context in which vaccines and immunization have been identified by the international community as being crucial to international development efforts and, in particular, the millennium development goals. However, past experience with innovations shows that realizing a technology’s potential can be difficult and complex. To achieve better societal embedding of synthetic biology and to make sure it reaches its potential, science and technology development should be made more inclusive and interactive. Responsible research and innovation is based on the premise that a broad range of stakeholders with different views, needs and ideas should have a voice in the technological development and deployment process. The interactive learning and action (ILA) approach has been developed as a methodology to bring societal stakeholders into a science and technology development process. This paper proposes an ILA in five phases for an international effort, with national case studies, to develop socially robust applications of synthetic biology for global health, based on the example of vaccine development. The design is based on results of a recently initiated ILA project on synthetic biology; results from other interactive initiatives described in the literature; and examples of possible applications of synthetic biology for global health that are currently being developed.  相似文献   
29.
目的探讨互动式教学法在医学本科医学微生物学教学中的应用效果。方法从2011级临床专业学生中随机抽取两个班作为实验班和对照班,实验班采用互动式教学法进行授课,对照班采用传统教学法进行授课。学习结束时对两班的学生用同一试卷进行理论考试和问卷调査。结果采用互动式教学法的实验班考试成绩明显高于对照班。结论互动式教学法能够提高学生的学习积极性和独立思考的能力,有利于创新型医学人才的培养。  相似文献   
30.
针对长江中游棉区棉花多虫复合危害问题,设计了6种害虫4种组合的复合危害系统。运用通径分析方法,定量描述了多种害虫对棉花的侵害及其间的互作效应。通过多种害虫对棉花产量和品级的直接影响效应和间接影响效应分析,认为当多虫复合危害时,害虫间的相互作用就其对作物的侵害而言,表现为增强效应和减弱效应。在此基础上,研究并制定了“两红”(棉红铃虫和朱砂叶螨)复合危害动态防治指标,经验证、示范及推广应用,取得了显着的经济、生态和社会效益。  相似文献   
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