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1.
The World Wide Web has become an important resource for public awareness and for educating the world’s population, including its political leaders, students, researchers, teachers, and ordinary citizens seeking information. Relevant information on photosynthesis-related web sites is grouped into several categories: (1) group sites, (2) sites by subject, (3) individual researcher’s sites, (4) sites for educators and students, and (5) other useful sites.  相似文献   

2.
For several years now, the World Wide Web (WWW) has left the realm of information technology and represents a fundamental everyday working tool for a wide variety of disciplines. Aerobiology, though a newcomer in this virtual space, is proceeding at a fast pace towards the creation of an easily accessible and effective information network. The web gives access to text, imagery, movie and sound with relatively low-cost and user-friendly interfaces conceived as graphical magazines. A practical way to start navigating and looking for information is to operate a ‘search engine’ which is a large database containing addresses on a wide spectrum of subjects. As an alternative, a few selected sites exist that can initialize your search by providing a thematic list of addresses. After leaving the entry ‘port’ you are directed from site to site and eventually end up with a lot more information than you initially thought. Excerpts: information on public and private institutions, access to databases and image catalogs, bibliographical information, overview of monitoring networks, directions on national and international research programs, news (calendar of meetings, courses, etc.). Information is provided for the non-expert user who asks himself the key questions: ‘Where do I start to browse the net?’ or ‘Can I become a provider of information on the net and, if so, is it terribly difficult?’ The idea is that everybody can in principle become a ‘surfer’ or a ‘provider’ dedicating a reasonable amount of time and effort to the task. What one ends up with is an easy-to-use and powerful tool that is already helping the whole aerobiological community to pursue its goals and reach out for necessary interdisciplinary approaches to unsolved scientific issues. The server AEROBIOLOGY INTERNATIONAL (http://www.fisbat.bo.cnr.it/AERO/) is presented as an example on how to proceed with the creation of a new server and its management.  相似文献   

3.
There is some evidence to suggest that undergraduate biology students need to be given more opportunities for reflection in their education. Some argue that computer-based learning packages may be able to offer such opportunities. This paper presents four different approaches to defining what reflection is and how it can be promoted. These approaches are then used to discuss and review the different ways in which computer-based tutorials can be used to promote lateral thinking. An example of a web-based biology tutorial called ‘How Now Mad Cow’ is described and preliminary evaluation results are presented, in order to illustrate how students may be encouraged to reflect and what factors may influence that. Finally, the role of the tutor in enspiring students to reflect while using computer-based tutorials is discussed. This distinguishes between the role of the tutor in designing a computer-based tutorial, and the role of the tutor in determining and facilitating how a student uses a tutorial once it has been designed.  相似文献   

4.
The NCBI (National Center for Biotechnology Information) at the National Institutes of Health collects a wide range of molecular biological data, and develops tools and databases to analyse and disseminate this information. Many life scientists are familiar with the website maintained by the NCBI (http://www.ncbi.nlm.nih.gov), because they use it to search GenBank for homologues of their genes of interest or to search the PubMed database for scientific literature of interest. There is also a database called the Bookshelf that includes searchable popular life science textbooks, medical and research reference books and NCBI reference materials. The Bookshelf can be useful for researchers and educators to find basic biological information. This article includes a representative list of the resources currently available on the Bookshelf, as well as instructions on how to access the information in these resources.  相似文献   

5.
In 1996, two searchable databases covering insect pathogens were posted on the World Wide Web: the Ecological Database of the World's Insect Pathogens (EDWIP) and the Viral Diseases of Insects in the Literature database (VIDIL). In this paper, we describe the format and contents of EDWIP and VIDIL on the World Wide Web. EDWIP contains over 9,400 pathogen-host association records, 677 negative test result or "no association" records, 4,454 host species, 2,285 pathogen species records, and 2,057 bibliographical references. Species of Coleoptera and Lepidoptera are the best represented groups in EDWIP. Lepidopteran species account for the most associations of any host order in EDWIP, over 2,500, or 27%. Of the pathogen groups, Protozoa (including microsporidia) accounted for nearly 66% of the pathogen species records and over 40% of the association records in EDWIP. Fungi account for only 18% of the pathogen species, but nearly 33% of the association records. Habitats dominated by human activities (e.g., crop, stored product, and human dwelling) account for most of the host habitats recorded in EDWIP. The United States and Japan are the most common locations and the Nearctic and Palearctic are the most common biogeographic regions reported in EDWIP. There are 4,801 annotated bibliographic records in VIDIL.  相似文献   

6.
2019新型冠状病毒信息库   总被引:14,自引:0,他引:14  
2019年12月在中国武汉开始爆发的新型肺炎已造成全球25个国家/地区的31516人感染、638人死亡(截止2020年2月7日16时),引起该肺炎的病毒被世界卫生组织命名为2019新型冠状病毒(2019-nCoV)。为促进2019-nCoV数据共享应用并及时向全球公众提供病毒的相关信息,国家生物信息中心(CNCB)/国家基因组科学数据中心(NGDC)建立了2019新型冠状病毒信息库(2019nCoVR,https://bigd.big.ac.cn/ncov)。该信息库整合了来自德国全球流感病毒数据库、美国国家生物技术信息中心、深圳(国家)基因库、国家微生物科学数据中心及CNCB/NGDC等机构公开发布的2019-nCoV核苷酸和蛋白质序列数据、元信息、学术文献、新闻动态、科普文章等信息,开展了不同冠状病毒株的基因组序列变异分析并提供可视化展示。同时,2019nCoVR无缝对接CNCB/NGDC的相关数据库,提供新测序病毒株系的基因组原始测序数据、组装后序列的在线汇交、管理与共享、国际数据库同步发布等数据服务。本文对2019nCoVR数据汇交、管理、发布及使用等进行全面阐述,以方便用户了解该信息库各项功能及数据状况,为加速开展病毒的分类溯源、变异演化、快速检测、药物研发以及新型肺炎的精准预防与治疗等研究提供重要基础。  相似文献   

7.
Science teachers are on the front lines of the evolution wars, not only in prominent court cases but also in everyday classroom situations. Owing both to religious opposition to and common misconceptions about evolution, science teachers are in need of support and sometimes guidance. Staff from the National Center for Science Education are looking forward to contributing a regular column, “Overcoming obstacles to evolution education,” to Evolution: Education and Outreach, which will discuss a variety of obstacles to effective evolution education and suggest ways of overcoming them.  相似文献   

8.
Dinucleotide frequencies are useful for characterizing consensus elements as a minimum unit of nucleotide sequence because the neighborhood relations of nucleotide sequences are reflected in dinucleotides. Using a consensus score based on dinucleotide frequencies and intra-species codon usage heterogeneity, denoted by the Z1 parameter, we report the relationship between nucleotide conservation at the translation initiation sites of genes in the Escherichia coli K-12 genome (W3110) and codon usage in its downstream genes. Significant positive correlations were obtained in three regions centered at -13, -4, and +7, which correspond to the Shine-Dalgarno element, the A + T element immediately upstream of the translation initiation site, and the downstream box, respectively.  相似文献   

9.
Protein sequence data are as useful and valuable today as was envisioned by pioneering sequencers and by the organizers of the first sequence database. Sequence analysis was first the province of specialists who developed search, comparison, and tree-building methods. Microcomputers, communication satellites, and the Internet have made these methods accessible to any scientist. The rapid increase in the data has driven a succession of changes in how databases are compiled, distributed, and accessed. Large public databases have become international collaborations. Although they need to develop still more efficient ways to accumulate, organize, annotate, and standardize huge amounts of data, inadequate support is available for such efforts. Thus there will be greater reliance on direct input from the scientific community. The World Wide Web is essential but not sufficient for integrated access to related databases.  相似文献   

10.
In the present study, we developed a method for detecting sequences whose similarity to a target sequence is statistically significant and we examined the distribution of these sequences in the E. coli K-12 genome. Target sequences examined are as follows: (i) short repeat: Crossover hot-spot instigator (Chi) sequence, replication termination (Ter) sequence, and DnaA binding sequence (DnaA box); (ii) potential stem-loop structure repeats: palindromic unit (PU), boxC sequences, and intergenic repeat unit (IRU); (iii) potential RNA coding repeats: rRNAs, PAIR, TRIP, and QUAD; and (iv) potential protein coding repeats: insertion elements (ISs) and Long Direct Repeats (LDRs). We also examined the distribution of these sequences on leading and lagging strands. We obtained another four statistically significant LDR sequences with more than 187 bp matched to LDR-A near the LDR loci, suggesting that these regions might be used as high recombination hot spots for LDR. Adaptation of individual LDRs to E. coli genome is also discussed on the basis of codon usage.  相似文献   

11.
王勤花  张志强 《生态学报》2008,28(5):2424-2424~2429
世界自然基金会(WWF)<生命行星报告2006>的最新数据(2003 年)显示,从1961 年以来,人类的\"生态足迹\"已经增长了3倍.目前的生态足迹已经超出地球自身再生能力的25%.报告中的\"生命行星指数\"(LPI)显示出自1970年来脊椎动物的数量减少了大约1/3,生物多样性正快速持续地遭到损失.影响 \"生态足迹\"的最主要因素是生产和使用能源的方式.如生命行星指数所示那样,人类对释放CO2的燃料的需求在不断增长.这些影响气候变化的污染气体占到了生态足迹的48%.将生态足迹与\"人类发展指数\"(HDI)进行对比发现,目前全球的发展还在继续背离可持续发展之路,人类发展的代内不公平、代际不公平还在加剧,人类向可持续发展的转变之路仍遥远而漫长.  相似文献   

12.
13.
Many computer programmes exist for drawing and modelling small and large molecules. Small molecules related to the antitubercular drug ethambutol are discussed. Some specific software problems, with stereochemical representations, are illustrated. Incompatibility of molecular structure files produced by different programmes and different hardware are shown. The need for a standardised file format is stressed. © 1995 Wiley-Liss, Inc.  相似文献   

14.
Variations and similarities in our individual genomes are part of our history, our heritage, and our identity. Some human genomic variants are associated with common traits such as hair and eye color, while others are associated with susceptibility to disease or response to drug treatment. Identifying the human variations producing clinically relevant phenotypic changes is critical for providing accurate and personalized diagnosis, prognosis, and treatment for diseases. Furthermore, a better understanding of the molecular underpinning of disease can lead to development of new drug targets for precision medicine. Several resources have been designed for collecting and storing human genomic variations in highly structured, easily accessible databases. Unfortunately, a vast amount of information about these genetic variants and their functional and phenotypic associations is currently buried in the literature, only accessible by manual curation or sophisticated text text-mining technology to extract the relevant information. In addition, the low cost of sequencing technologies coupled with increasing computational power has enabled the development of numerous computational methodologies to predict the pathogenicity of human variants. This review provides a detailed comparison of current human variant resources, including HGMD, OMIM, ClinVar, and UniProt/Swiss-Prot, followed by an overview of the computational methods and techniques used to leverage the available data to predict novel deleterious variants. We expect these resources and tools to become the foundation for understanding the molecular details of genomic variants leading to disease, which in turn will enable the promise of precision medicine.  相似文献   

15.
In view of the upcoming 2002 World Summit in Johannesburg, sustainable development is a topic of high priority in South Africa. Although the South African competency in Life Cycle Assessment (LCA) and Life Cycle Engineering (LCE) has grown to some extent over the last ten years, South African industry and government have been slow to realise the benefit of LCAs and LCE as tools to support cleaner production and sustainable development. However, the local application of these tools, as well as considerations during their use, differs from practices in developed countries. The applications of LCAs and LCE, the type of organisations involved and the limitations and common problems associated with these tools in South Africa are discussed.  相似文献   

16.
    
The author interviewed Glenn Nierman on the occasion of the recent conclusion of his term as National Association for Music Education (NAfME) president. Topics included the current state of music education and advocacy of music education in the United States, the role of NAfME, and the recently revised national music education standards.  相似文献   

17.
In 1971, first bone bank was established at the Department of Orthopaedic Surgery in Catholic University of Korea. The first clinical case was reported at the Journal of Korean Orthopaedic Association in 1973. Subsequently, more than 60 surgical bone banks were established in the university and teaching hospitals throughout country. In 1990, the Korea Biomaterial Research Institute (KBRI) organised the IAEA/RCA training course on tissue banking. In this course students from 17 countries participated. In 1994 the first collaboration for cadaver tissue recovery was performed. It is important to single out that the various religious groups in Korea have favourable attitudes towards tissue donation, which contributes to the success of the tissue banking programs in the country. The demands of allograft were getting increased in the Korean medical and dental society. Currently, 62 hospital based bone banks, 5 processing tissue banks, 1 regional tissue bank and more than 30 tissue distributors are working in Korea. Based on the U.S.A. usage of more than 1,000,000 grafts per year, 100,000–200,000 grafts will be needed in Korea. Those findings indicate a greatly increased need for training of tissue bank operators. The Korean society will need at least 20–30 tissue bank operators for training in every year. The National Training Centre (NTC) for tissue bank operators and medical personal using the IAEA Curriculum in the Korean languages was established in 2003. From 2004 to 2006, NTC have been trained 40 tissue bank operators. They have produced at least 10,000 tissues per year. These figures indicate a cost saving of US$ 10 million. Within 5 years, NTC will train 100 tissue bank operators. These individuals and their respective banks will provide an increasing number of high quality grafts to the communities they serve at a cost far less than if they were acquired from abroad.  相似文献   

18.
19.

Twenty-five newly bred improved cassava cultivars, twenty-three improved from the International Institute of Tropical Agriculture and two local cultivars were evaluated for their relative resistance to African cassava mosaic begomovirus disease (ACMD) at Ibadan, in an area of high disease pressure representative of the forest/savanna transition zone of Nigeria. These cultivars were exposed to natural infection by the viruliferous whiteflies ( Bemisia tabaci Gennadius) and the disease incidence (DI) and index of symptom severity (ISS) were assessed for all clones. Results for the Rank-sum (i.e., sum of ranks for DI and ISS for each cultivar) and the area under the disease progress curve (AUDPC) were used to assess the relative resistance of the cassava clones. Those that showed low Rank-sum and AUDPC values were rated 'moderately resistant (MR)', 'resistant ( R )', and 'highly resistant (HR)' to ACMD depending on their respective values and deviation from the mean distribution curve. Clones M94/0121 and 94/0239 were rated HR under the two methods. Clone M94/0583 was rated HR under the AUDPC with a deviation from the mean distribution curve of m 2.00 while it was rated R under the Rank-sum method with a deviation from the mean distribution of m 1.99. Also plants of clones ISU and TMS 30572 were rated highly susceptible (HS) under both methods. Clone TME-1 was intermediate between Moderately resistant (MR) and Moderately susceptible (MS) under the AUDPC method with a deviation from the mean distribution of 0.00 but observed to be MS under the Rank-sum method with a deviation of + 0.2. The two methods of evaluation gave similar results as revealed by Spearman rank correlation ( r equals; 0.99, P <0.01). However, the AUDPC method is less cumbersome compared to the Rank-sum method. None of the clones was observed to be immune to the disease.  相似文献   

20.
The dramatic growth of distributed computing applications is creating both an opportunity and a daunting challenge for users seeking to build applications that will play critical roles in their organization. Here, we discuss the use of a new system, Astrolabe, to automate self-configuration, monitoring, and to control adaptation. Astrolabe operates by creating a virtual system-wide hierarchical database, which evolves as the underlying information changes. Astrolabe is secure, robust under a wide range of failure and attack scenarios, and imposes low loads even under stress. To focus the discussion, we structure it around a hypothetical Web Services scenario. One of the major opportunities created by Astrolabe is to allow Web Services client systems to autonomically adapt when a data center becomes slow or unreachable. The authors were supported by Intel Corporation, DARPA/AFRL grant RADC F30602-99-1-0532, by AFOSR/MURI grant F49620-02-1-0233, Microsoft Research BARC and the Cornell/AFRL Information Assurance Institute.  相似文献   

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