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We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of taxonomic systems in these taxa. Establishing phylogenetic hypotheses using DNA sequences, from which an understanding of the natural evolutionary relationships amongst clades may be derived, requires a robust dataset. It has been recognized that single-gene phylogenies may not truly represent organismal phylogenies, but the concordant phylogenetic genealogies from multiple-gene datasets can resolve this problem. The genes commonly used in mushroom phylogenetic research are summarized.  相似文献   
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This paper discusses the evaluation of scientific activity with the help of some scientometric indices, in particular, a citation index. The information massif of the bibliographic database of citations to domestic publications of Kazakh authors is statistically described.  相似文献   
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The necessity for publishing a separate abstract journal on spintronics, which is a new, rapidly developing branch of physics, is substantiated. The interest in spintronics, which is the study of fundamental processes involving the simultaneous transport of both electron charge and electron spins in solids, as well as the interaction of electrons with a magnetic grating, is determined not only by its fascinating prospects but also the results that have already achieved. The spin and charge “degrees of freedom” open possibilities for the creation of semiconducting devices with parameters that are much superior to the existing ones and also the construction of devices that do not have analogues at present. First of all, this will permit problems of information transmission and processing to be solved in a new way. A detailed rubrication on spintronics is given in order to discuss the possibility of publishing a separate edition of an abstract journal devoted to spintronics.  相似文献   
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Conclusions Palestinian teachers at the pre-collegiate level who participate in the CEEPAT programme will, it is hoped, learn to place new emphasis on enhancement of their students' analytical skills and discourage an identification of knowledge with memorisation. For their part, Palestinian professors who have been trained to teach in the programme will presumably constitute a growing reservoir of talent which may be expected to raise the quality of Palestinian university education. Plans are now under way to give all Palestinians teaching under the auspices of CEEPAT an opportunity to attend an annual, three-week winter seminar in Gaza and/or a summer seminar in the United States, both of which will focus on issues of pedagogy and methodology. Such professors can be expected to pass on their new understanding of teaching via discussion to their colleagues and to their university students, thereby spreading an important pedagogical method to other segments of the Palestinian... community. 7 CEEPAT clearly has the potential to make a significant contribution to the elevation of educational standards in Palestine at a time of major historical change.In Palestine, higher education of quality is obviously a very serious business. It is understood that it underlies any possibility of individual betterment, economic development, or the evolution of an independent Palestinian state. If ever the Israeli occupation is completely terminated and the present financial crisis of the universities is solved, Palestinian university and post-baccalaureate training may reasonably be expected to become fully competitive on an international scale.  相似文献   
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The purpose of the study was to identify the pattern of publication about women and AIDS in scientific journals. Bradford zones were identified in each of six databases. The study determined that journal scatter for this subset of AIDS literature differed from the scatter in the general literature; further, the information indexed in the six electronic sources demonstrated little overlap. Consequently, key journal and newsletter titles identified by this study should form the core of any collection focusing on women and AIDS. The assurance of quality patient care management demands that librarians consult multiple resources for information retrieval that can assist health care providers, patients, and caregivers to enhance quality of life as well as to provide optimum care.  相似文献   
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