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1.
Gómez  Nora  Bauer  Delia E. 《Hydrobiologia》1998,386(1-3):1-8
Opinion This is a series of contributions, expressing explicit opinions with regard to contemporary topics in limnology. These texts will mostly be based on new books with a large impact, but can also refer to other currently debated topics. Documented reactions to these contributions should be sent to the editor-in-chief; they will be considered for publication in subsequent issues. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

2.
Twitter is an extremely high volume platform for user generated contributions regarding any topic. The wealth of content created at real-time in massive quantities calls for automated approaches to identify the topics of the contributions. Such topics can be utilized in numerous ways, such as public opinion mining, marketing, entertainment, and disaster management. Towards this end, approaches to relate single or partial posts to knowledge base items have been proposed. However, in microblogging systems like Twitter, topics emerge from the culmination of a large number of contributions. Therefore, identifying topics based on collections of posts, where individual posts contribute to some aspect of the greater topic is necessary. Models, such as Latent Dirichlet Allocation (LDA), propose algorithms for relating collections of posts to sets of keywords that represent underlying topics. In these approaches, figuring out what the specific topic(s) the keyword sets represent remains as a separate task. Another issue in topic detection is the scope, which is often limited to specific domain, such as health. This work proposes an approach for identifying domain-independent specific topics related to sets of posts. In this approach, individual posts are processed and then aggregated to identify key tokens, which are then mapped to specific topics. Wikipedia article titles are selected to represent topics, since they are up to date, user-generated, sophisticated articles that span topics of human interest. This paper describes the proposed approach, a prototype implementation, and a case study based on data gathered during the heavily contributed periods corresponding to the four US election debates in 2012. The manually evaluated results (0.96 precision) and other observations from the study are discussed in detail.  相似文献   

3.
The geosciences contribution along the 50 years of the Revista de Biología Tropical had been scarcity and episodic. Until now there are 2374 papers but only 21 (0.88%) have some relation with geological sciences. It's possible to recognize two periods with geological contributions, one between 1963 and 1978. It's appropriate to underline the importance of the biologist L. D. Gómez with his contributions about Costa Rican Paleobotanic in this period. The other period includes from 1988 to the present, and it's typified by an increase of biologist and geologist participation in different topics regarding with geosciences. Foreign and national researches are in the same ratio and belong from several countries like Costa Rica, México and Dominican Republic. The subjects are concerning mainly about fossil taxonomy (Paleontology: 81%), only 19% are related with geological topics. Such distribution could be explained because the affinity between the fossil studies and the biological sciences.  相似文献   

4.
This Special Feature of the Journal of Vegetation Science contains ten contributions from the 56th Symposium of the International Association for Vegetation Science (IAVS), which was held in Tartu, Estonia, 26–30 Jun 2013, and focused on processes underlying vegetation patterns. These contributions give an overview of recent advances in vegetation science, with topics ranging from the introduction of new methods and ideas to comprehensive analysis of vegetation patterns on a global scale. The focus of these Special Feature contributions indicates that vegetation science is becoming more global, more complex and more interdisciplinary. It is likely that progress in methods and accumulation of data have led vegetation science into a ‘new era of discovery’.  相似文献   

5.

Background

This paper summarizes the contributions from the Genome-wide Association Study group (GWAS group) of the GAW20. The GWAS group contributions focused on topics such as association tests, phenotype imputation, and application of empirical kinships. The goals of the GWAS group contributions were varied. A real or a simulated data set based on the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study was employed by different methods. Different outcomes and covariates were considered, and quality control procedures varied throughout the contributions.

Results

The consideration of heritability and family structure played a major role in some contributions. The inclusion of family information and adaptive weights based on data were found to improve power in genome-wide association studies. It was proven that gene-level approaches are more powerful than single-marker analysis. Other contributions focused on the comparison between pedigree-based kinship and empirical kinship matrices, and investigated similar results in heritability estimation, association mapping, and genomic prediction. A new approach for linkage mapping of triglyceride levels was able to identify a novel linkage signal.

Conclusions

This summary paper reports on promising statistical approaches and findings of the members of the GWAS group applied on real and simulated data which encompass the current topics of epigenetic and pharmacogenomics.
  相似文献   

6.
Spoken language communication is arguably the most important activity that distinguishes humans from non-human species. This paper provides an overview of the review papers that make up this theme issue on the processes underlying speech communication. The volume includes contributions from researchers who specialize in a wide range of topics within the general area of speech perception and language processing. It also includes contributions from key researchers in neuroanatomy and functional neuro-imaging, in an effort to cut across traditional disciplinary boundaries and foster cross-disciplinary interactions in this important and rapidly developing area of the biological and cognitive sciences.  相似文献   

7.
Biology and law     
《Ethology and sociobiology》1986,7(3-4):167-173
The terms “biology” and “biological” are widely used in ways that confuse and denigrate possible contributions of biologists to human self-understanding. As with social scientists, biologists deal with learning, developmental plasticity, and strategizing in virtually all species they study. It is from theories about how human strategizing is molded by selection that biologists can contribute to understanding topics like law.  相似文献   

8.
Traditionally, Russian physiologists have been much concerned with topics at the borders between physiology and psychology, in particular the function of the special senses ("analyzers," in Pavlovian terminology), the central nervous system, and the neuromuscular apparatus. The psychophysiology of movement and the psychophysiology of the sensory organs have come to represent areas in which major contributions have been made.  相似文献   

9.
民族昆虫学简介   总被引:1,自引:0,他引:1  
梁宏斌  张润志 《昆虫知识》2001,38(4):314-319
民族昆虫学是研究在非工业化社会中人与昆虫关系的科学。民族昆虫学的研究内容包括 :昆虫的食用、药用、观赏 ,利用昆虫娱乐和装饰 ,有害昆虫防治 ,昆虫崇拜和关于昆虫的神化传说等。研究民族昆虫学的方法有查阅文献和实地调查 ,两种方法相互补充。中国有许多民族处于偏远封闭的环境里 ,研究和挖掘他们与昆虫的相对独特的关系 ,吸收其成功的昆虫利用或防治经验 ,对促进各民族间交流和发展具有重要意义  相似文献   

10.
Abstract

A survey of all the 154 scientific publications of Emilio Battaglia (1917–2011) is presented, grouped in three main research interests – plant embryology, cytogenetics in plants and cytological terminology – plus other less relevant contributions. Battaglia's past and present role in these disciplines is briefly discussed, in the light of current research on these topics, partly reviewed also in other contributions of the present Plant Biosystems issue.  相似文献   

11.
This commentary' calls for an appreciative but rigorous, critical analysis of three pioneering figures in the anthropology of human movement and visual aspects of human communication. I maintain that their many theoretical and methodological contributions require historical contextualization, taking into account earlier paradigms, subsequent developments, and alternative approaches. The essay makes a number of suggestions for developing a more satisfying historical framework and raises topics for further discussion.  相似文献   

12.
Inorganic and bioinorganic chemistry have made important contributions to medical science and human health in the past half century. Today, metal-containing imaging agents and therapeutics constitute a multi-billion dollar industry. Recent discoveries in bioinorganic chemistry of potential biomedical importance include the use of metal ions as synthetic scaffolds for the preparation of small molecule therapeutics, which opens up a new route to molecular structure and diversity, as well as the examination of metal-organic frameworks as biological imaging and drug delivery agents. These areas represent some of the most recent and still relatively unexplored themes in inorganic and bioinorganic chemistry that might be exciting and fruitful topics of study for the community interested in 'metals in medicine'.  相似文献   

13.
It has been postulated many times that different scientific topics and strategies often encounter each other, which create cutting edge research field resulting in further significant progresses of science. This was also a lesson bestowed by Prof. Raymond Wegmann where he created innovative research field for biology, molecular biology and biochemistry-biophysics. Progresses of developmental biology were boosted by molecular biology and reproductive engineering where ES cells and embryonic manipulation are necessary. There are no questions about the utility of their technologies. Reviews on their contributions with respect to the condition of genome manipulation are addressed.  相似文献   

14.
This paper explores the origins and content of neurocybernetics and its links to artificial intelligence, computer science and knowledge engineering. Starting with three remarkable pieces of work, we center attention on a number of events that initiated and developed basic topics that are still nowadays a matter of research and inquire, from goal directed activity theories to circular causality and to reverberations and learning. Within this context, we pay tribute to the memory of Prof. Ricciardi documenting the importance of his contributions in the mathematics of brain, neural nets and neurophysiological models, computational simulations and techniques.  相似文献   

15.
Fruehauf S  Ho AD 《Cytotherapy》2005,7(3):301-308
The call for the meeting which took place in Heidelberg 13 January 2005, resulted in a high number of contributions covering a diversity of topics: embryonal stem cell research; molecular signaling pathways; assay systems for primitive, mesenchymal and epithelial stem cells; markers for transdifferentiation; and theoretical considerations including biomathematical modeling of stem cell development. The program was rounded off by pre-clinical and clinical applications of stem cell therapies, including new mobilization agents, treatment of myocardial infarction and chemoprotective gene transfer to stem cells.  相似文献   

16.
Plankton population dynamics: food web interactions and abiotic constraints   总被引:1,自引:0,他引:1  
1. In this introduction, I try to follow some developments in plankton ecology, how they have led to current research topics, and how the contributions in this issue of Freshwater Biology are related to these fields of research.
2. Due to several favourable features, such as small size, short generation time and a relatively homogeneous habitat, planktonic organisms remain ideal subjects for theoretical and experimental population ecology.
3. Important current research topics involve: (1) the control of plankton communities by external abiotic factors; (2) bottom-up (limitation by resources) and top-down (control by predators) effects in the food web; (3) the importance of dormant resting stages and benthic–pelagic coupling in plankton dynamics; (4) costs and benefits of the mixotrophic strategy, i.e. the ability to combine a phototrophic and a phagotrophic mode of nutrition.  相似文献   

17.
This work presents some of the author's reflections, the purpose of which is to give an orientation on the present stage and recent developments in the investigations of the theory of homogeneous structures and their applications. This survey appears to be desirable at this time because a number of research workers in mathematical and theoretical biology are becoming interested in making contributions in the theory of homogeneous structures and their applications. It is hoped that this survey will provide a stimulus and some introduction to the subject. The choice of topics is dictated largely by my predilections, and in no way shall I attempt to illustrate the vast and rapidly increasing field of applications of mathematical techniques or even, more generally, the mathematical mode of thinking in the enormous variety of problems in the theory of homogeneous structures and its applications, including biology. Indeed, to present anything like a comprehensive picture would require bulky and manifold volumes of very heterogeneous contributions. However, I shall list a number of biological and engineering fields where techniques of homogeneous structures have been employed and give the reader a short indication of selected bibliographic aids.  相似文献   

18.
This article starts from the assumption that there are various innate contributions to our view of the world and explores the epistemological implications that follow from this. Specifically, it explores the idea that if certain components of our worldview have an evolutionary origin, this implies that these aspects accurately depict the world. The simple version of the argument for this conclusion is that if an aspect of mind is innate, it must be useful, and the most parsimonious explanation for its usefulness is that it accurately depicts the world. There are a number of important criticisms of this argument. These include the idea that evolutionary justifications are circular, that evolved mental content and principles are not necessarily accurate, and that, if the argument is taken seriously, it has some highly dubious consequences. These criticisms necessitate various qualifications to the initial argument. Nonetheless, it is argued that, in some cases, important conclusions can be drawn about the world from an analysis of evolved contributions to our view of the world. An evolutionary approach cannot provide an ultimate justification for any belief; however, in certain circumstances, it supports the conclusion that a given belief is a reasonable first approximation. To the extent that innate content and principles pertain to topics in metaphysics, they can be viewed as a naturalistic source of metaphysical knowledge.  相似文献   

19.
Circumventricular organs (CVO) play a critical role as transducers of information between the blood, neurons and the cerebral spinal fluid (CSF). They permit both the release and sensing of hormones without disrupting the blood-brain barrier (BBB) and as a consequence of such abilities the CVOs are now well established to have essential regulatory actions in diverse physiological functions. The sensory CVOs are essential signal transducers located at the blood-brain interface regulating autonomic function. They have a proven role in the control of cardiovascular function and body fluid regulation, and have significant involvement in central immune response, feeding behavior and reproduction, the extent of which is still to be determined. This review will attempt to summarize the research on these topics to date. The complexities associated with sensory CVO exploration are intense, but should continue to result in valuable contributions to our understanding of brain function.  相似文献   

20.
Professor de Wilde's scientific contributions can be divided into two separate areas based on the applied methods: induction and deduction. The first method is used in the investigation of the finger ridge pattern and the second in that of the branching of bloodvessels. It is shown that with induction alternative classifications and explanations remain always possible and that the ultimate choice of the classification depends on supposed biological meanings or practical applicability. In the case of the finger ridge patterns the latter criterion is decisive. With the deductive method a sufficient logical explanation within the boundary conditions can be reached. Alternatives can be presented if the boundary conditions are changed or the functional parameters have to be chosen differently, which is necessary when direct observation (induction) "shows" that other functions are involved. A number of advantages and problematic points in both methods are analysed and their relationship and function in morphology are demonstrated in the mentioned research topics.  相似文献   

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