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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.
Hagen J 《Journal of the history of biology》2003,36(2):353-384
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.
Tomasz?S.?OsiejukEmail author Katarzyna?Ratyńska Jakub?P.?Cygan 《Journal of Ethology》2004,22(1):55-61
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.
Isokpehi R.D. Thomas B.N. Ojo A.K. Sofoluwe A.B. Coker A.O. 《World journal of microbiology & biotechnology》2000,16(5):423-424
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.
A. Wieke Betten Anneloes Roelofsen Jacqueline E. W. Broerse 《Systems and synthetic biology》2013,7(3):127-138
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
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