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1.
周晴  潘晓云 《植物生态学报》2014,38(10):1093-1098
为了探究凤眼蓝(别名凤眼莲, Eichhornia crassipes)入侵中国南部基塘区的主要原因, 对历史文献与档案资料进行了综合分析, 结果表明: 凤眼蓝在中国大陆的出现早于1930年。1911年后, 凤眼蓝曾入侵浙江省杭嘉湖平原水网河道。凤眼蓝也是1911年以来珠江三角洲地区十分常见的水生植物。1911-1980年, 基塘农业是浙江省的杭嘉湖地区和广东省珠江三角洲地区的典型农业经营模式, 凤眼蓝在这两个地区都曾被用作有机肥。20世纪50年代末至70年代, 长江流域曾推广凤眼蓝栽培技术, 对凤眼蓝进行了大规模的养植, 但1950-1980年的广积肥运动控制了凤眼蓝的繁殖速度和规模。1980年以来, 基塘地区成为长江三角洲和珠江三角洲城镇化与工业化快速发展的区域, 传统的循环农业经营模式普遍被废弃, 同时, 基塘区河网湿地水文生态环境的改变是凤眼蓝入侵中国南部基塘区的主要原因。  相似文献   

2.
Protein identification using MS is an important technique in proteomics as well as a major generator of proteomics data. We have designed the protein identification data object model (PDOM) and developed a parser based on this model to facilitate the analysis and storage of these data. The parser works with HTML or XML files saved or exported from MASCOT MS/MS ions search in peptide summary report or MASCOT PMF search in protein summary report. The program creates PDOM objects, eliminates redundancy in the input file, and has the capability to output any PDOM object to a relational database. This program facilitates additional analysis of MASCOT search results and aids the storage of protein identification information. The implementation is extensible and can serve as a template to develop parsers for other search engines. The parser can be used as a stand-alone application or can be driven by other Java programs. It is currently being used as the front end for a system that loads HTML and XML result files of MASCOT searches into a relational database. The source code is freely available at http://www.ccbm.jhu.edu and the program uses only free and open-source Java libraries.  相似文献   

3.
Oblong, a program with very low memory requirements, is presented. It is designed for parsimony analysis of data sets comprising many characters for moderate numbers of taxa (the order of up to a few hundred). The program can avoid using vast amounts of RAM by temporarily saving data to disk buffers, only parts of which are periodically read back in by the program. In this way, the entire data set is never held in RAM by the program—only small parts of it. While using disk files to store the data slows down searches, it does so only by a relatively small factor (4× to 5×), because the program minimizes the number of times the data must be accessed (i.e. read back in) during tree searches. Thus, even if the program is not designed primarily for speed, runtimes are within an order of magnitude of those of the fastest existing parsimony programs.  相似文献   

4.
Umansky J  Taub P  Lorenz HP  Kawamoto HK 《Plastic and reconstructive surgery》2003,111(3):981-4; discussion 985-6
Plastic surgery residency program directors are frequently interested in predictors of future career direction in their applicants. Many programs strive to train leaders in academic plastic surgery. To determine what factors may predict the ultimate fate of graduating plastic surgery residents, the authors reviewed the application files of 33 former residents from a single, major plastic surgery training program. The data from 29 residents were available for analysis. Nearly half of the residents graduating from the plastic surgery training program went into private practice. Two factors, the number of years taken off for research before entering the plastic surgery residency and the presence of children, were found to be indicative of a candidate's future career path. Of particular note, there was no difference between academic graduates and nonacademic graduates with regard to their intentions in their letters of recommendation and personal statements. This information is useful to both academic program directors and resident applicants.  相似文献   

5.
We report the development of a prototype database that "maps" microbial diversity in the context of the geochemical and geological environment and geographic location. When it is fully implemented, scientists will be able to conduct database searches, construct maps containing the information of interest, download files, and enter data over the Internet.  相似文献   

6.
《Journal of Proteomics》2010,73(2):357-360
We developed a software program (titled Precursor Ion Calibration software for LTQ or, in short, PICsL) that increases the reliability of precursor ion assignations from LC-MS analysis using ultra zoom scanning of LTQ linear ion trap MS and automatically corrects the assignations. Although existing software calculates the theoretical isotopic distribution according to m/z with a computational algorithm, our method simply searches for ions close to the theoretical mass value using both MS/MS raw data and Mascot search result files, followed by a second database search that identifies the proteins using the regenerated peak list files. Our software program mimics the manual inspection of the spectral data of precursor ions and is expected to be applicable not only for low resolution MS, such as LTQ, but also for a wide variety of MS instruments.  相似文献   

7.
Mapping Microbial Biodiversity   总被引:1,自引:1,他引:0       下载免费PDF全文
We report the development of a prototype database that “maps” microbial diversity in the context of the geochemical and geological environment and geographic location. When it is fully implemented, scientists will be able to conduct database searches, construct maps containing the information of interest, download files, and enter data over the Internet.  相似文献   

8.
An open-source tool capable of converting SD files (and virtually any other format through OpenBabel) into MMFF-typed XYZ coordinate files to be used with TINKER is described. SDF2XYZ2SDF allows including the power of TINKER molecular mechanics computations in automated cheminformatics workflows, such as conformational searches and virtual screening protocols.  相似文献   

9.
BioCloneDB     
BioCloneDB is a user-friendly database with a web interface to assist molecular genetics laboratories in managing a local repository of sequence information linked to DNA clones. This tool is designed to assist in high-throughput sequence and gene expression projects, providing a link between both types of information. The unique feature of the application is the automation of batch sequence annotation following BLAST((R)) searches, which is supported by easy-to-use web interfaces. Furthermore, any set of sequences can be annotated against any sequence database. This replaces the need to perform and analyse individual web BLAST((R)) searches or the need to learn how to produce batch searches and perform analysis in a UNIX((R)) operating system. BioCloneDB is open-source software that can be installed on Linux or UNIX((R)) operating systems. To test the application, we used 1400 expressed sequence tags obtained from the filamentous fungus Neurospora crassa. The results were analysed and compared with published results and they show a significant change due to the accumulation of the data in the nr database (ftp://ftp.ncbi.nih.gov/blast/db/). AVAILABILITY: BioCloneDB is available for academic use along with documentation, screenshots, database scheme and readme files at http://bioclonedb.agri.huji.ac.il/ CONTACT: Oded Yarden (Oded.Yarden@huji.ac.il).  相似文献   

10.

Background

The expressed sequence tag (EST) methodology is an attractive option for the generation of sequence data for species for which no completely sequenced genome is available. The annotation and comparative analysis of such datasets poses a formidable challenge for research groups that do not have the bioinformatics infrastructure of major genome sequencing centres. Therefore, there is a need for user-friendly tools to facilitate the annotation of non-model species EST datasets with well-defined ontologies that enable meaningful cross-species comparisons. To address this, we have developed annot8r, a platform for the rapid annotation of EST datasets with GO-terms, EC-numbers and KEGG-pathways.

Results

annot8r automatically downloads all files relevant for the annotation process and generates a reference database that stores UniProt entries, their associated Gene Ontology (GO), Enzyme Commission (EC) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) annotation and additional relevant data. For each of GO, EC and KEGG, annot8r extracts a specific sequence subset from the UniProt dataset based on the information stored in the reference database. These three subsets are then formatted for BLAST searches. The user provides the protein or nucleotide sequences to be annotated and annot8r runs BLAST searches against these three subsets. The BLAST results are parsed and the corresponding annotations retrieved from the reference database. The annotations are saved both as flat files and also in a relational postgreSQL results database to facilitate more advanced searches within the results. annot8r is integrated with the PartiGene suite of EST analysis tools.

Conclusion

annot8r is a tool that assigns GO, EC and KEGG annotations for data sets resulting from EST sequencing projects both rapidly and efficiently. The benefits of an underlying relational database, flexibility and the ease of use of the program make it ideally suited for non-model species EST-sequencing projects.  相似文献   

11.
12.
Amplified fragment length polymorphism (AFLP), a widely used method for DNA fingerprinting, has shifted from polyacrylamide gel to capillary electrophoresis over the last years. Currently, most AFLP data are generated in a computer-readable format, and several programs are available that automatically score raw data into binary profiles. Good scoring parameters are the key to good AFLP profiles. optiFLP is the first open source program for automatic optimization of AFLP scoring parameters. It searches parameter space to maximize the contrast among groups of AFLP profiles, with the allocation of profiles to groups in either a supervised or an unsupervised mode. The software produces output files ready for use in a range of downstream applications.  相似文献   

13.
Shared ecological data have the potential to revolutionize ecological research just as shared genetic sequence data have done for biological research. However, for ecological data to be useful, it must first be discoverable. A broad-scale research topic may require that a researcher be able to locate suitable data from a variety of global, regional and national data providers, which often use different local languages to describe their data. Thus, one of the challenges of international sharing of long-term data is facilitation of multilingual searches. Such searches are hindered by lack of equivalent terms across languages and by uneven application of keywords in ecological metadata. To test whether a thesaurus-based approach to multilingual data searching might be effective, we implemented a prototype web-services-based system for searching International Long-Term Ecological Research Network data repositories. The system builds on the use of a multilingual thesaurus to make searches more complete than would be obtained through search term-translation alone. The resulting system, when coupled to commodity online translation systems, demonstrates the possibility of achieving multilingual searches for ecological data.  相似文献   

14.
MOTIVATION: The large and growing body of experimental data on biomolecular binding is of enormous value in developing a deeper understanding of molecular biology, in developing new therapeutics, and in various molecular design applications. However, most of these data are found only in the published literature and are therefore difficult to access and use. No existing public database has focused on measured binding affinities and has provided query capabilities that include chemical structure and sequence homology searches. METHODS & RESULTS: We have created Binding DataBase (BindingDB), a public, web-accessible database of measured binding affinities. BindingDB is based upon a relational data specification for describing binding measurements via Isothermal Titration Calorimetry (ITC) and enzyme inhibition. A corresponding XML Document Type Definition (DTD) is used to create and parse intermediate files during the on-line deposition process and will also be used for data interchange, including collection of data from other sources. The on-line query interface, which is constructed with Java Servlet technology, supports standard SQL queries as well as searches for molecules by chemical structure and sequence homology. The on-line deposition interface uses Java Server Pages and JavaBean objects to generate dynamic HTML and to store intermediate results. The resulting data resource provides a range of functionality with brisk response-times, and lends itself well to continued development and enhancement.  相似文献   

15.
Expressed sequence tags (ESTs) are generated and deposited in the public domain, as redundant, unannotated, single-pass reactions, with virtually no biological content. PipeOnline automatically analyses and transforms large collections of raw DNA-sequence data from chromatograms or FASTA files by calling the quality of bases, screening and removing vector sequences, assembling and rewriting consensus sequences of redundant input files into a unigene EST data set and finally through translation, amino acid sequence similarity searches, annotation of public databases and functional data. PipeOnline generates an annotated database, retaining the processed unigene sequence, clone/file history, alignments with similar sequences, and proposed functional classification, if available. Functional annotation is automatic and based on a novel method that relies on homology of amino acid sequence multiplicity within GenBank records. Records are examined through a function ordered browser or keyword queries with automated export of results. PipeOnline offers customization for individual projects (MyPipeOnline), automated updating and alert service. PipeOnline is available at http://stress-genomics.org.  相似文献   

16.
The Flora North America Program will create a computer data bank of taxonomic information about the vascular plants of North America north of Mexico. The system, which will serve a broad range of users, will provide for the acquisition, editing, and storage of data and the preparation of a variety of products. It will grow and evolve over a long period of time, continually incorporating changes to data and new categories of information as they become available. The system will utilize an existing computer program package, the IBM Generalized Information System (GIS), for creating, maintaining, querying, and generating reports from its files of data. In addition to a file of taxonomic, ecological, and geographic data about each taxon, the system will build and maintain a series of authority or dictionary files to control system content. The first major system product will be a published flora, generated by computer. Many other catalogs and indexes will be prepared and specific questions may be asked of the data bank to meet individual user needs for information.  相似文献   

17.
MOTIVATION: The program MBBC 2.0 clusters time-course microarray data using a Bayesian product partition model. RESULTS: The Bayesian product partition model in Booth et al. (2007) simultaneously searches for the optimal number of clusters, and assigns cluster memberships based on temporal changes of gene expressions. MBBC 2.0 to makes this method easily available for statisticians and scientists, and is built with three free computer language software packages: Ox, R and C++, taking advantage of the strengths of each language. Within MBBC, the search algorithm is implemented with Ox and resulting graphs are drawn with R. A user-friendly graphical interface is built with C++ to run the Ox and R programs internally. Thus, MBBC users are not required to know how to use Ox, R or C++, but they must be pre-installed. AVAILABILITY: A self-extractable zip file, MBBC20zip.exe, is available at the MBBC webpage www.stat.ufl.edu/~casella/mbbc/, which contains MBBC.exe, source files, and all other related files. The current version works only in the Windows operating system. A free installation program and overview for Ox is available at www.doornik.com. A detailed installation guide for Ox is provided by MBBC, and is accessible without installing Ox. R is available at www.r-project.org/.  相似文献   

18.
A computer program has been designed to aid development of synthetic strategies for oligonucleotides produced by solid-phase chemical techniques. The program reduces the time required to develop a strategy and a data file from hours to minutes. The program contains inventories, provides cost analyses, and generates and stores other associated data. The program searches an inventory of sequences for that sequence to avoid duplicate synthesis. If the sequence is not in the inventory the program devises a synthetic strategy, calculates the amounts of reagents and labor costs necessary to complete the synthetic oligonucleotide. The program also deducts the reagents from inventory files. Physical data is also calculated. A file is generated in a sequence inventory for storage of the data as well as other data that will be generated during the purification processes. All variable parameters can be easily edited. The programs were designed to provide a cross-referencing feature for data analysis and can use several parameters as a constant.  相似文献   

19.
Knowledge discovery from the exponentially growing body of structurally characterised protein-ligand complexes as a source of information in structure-based drug design is a major challenge in contemporary drug research. Given the need for powerful data retrieval, integration and analysis tools, Relibase was developed as a database system particularly designed to handle protein-ligand related problems and tasks. Here, we describe the design and functionality of the Relibase core database system. Features of Relibase include, e.g. the detailed analysis of superimposed ligand binding sites, ligand similarity and substructure searches, and 3D searches for protein-ligand and protein-protein interaction patterns. The broad range of functions provided in Relibase and its high level of data integration, along with its flexible and intuitive interface, makes Relibase an invaluable data mining tool which can significantly enhance the drug development process. An example, illustrating a 3D query for quarternary ligand nitrogen atoms interacting with aromatic ring systems in proteins, a pattern found in pharmaceutically relevant target proteins such as, e.g. acetylcholine-esterase, is discussed.  相似文献   

20.
MOSIX is a cluster management system that supports preemptive process migration. This paper presents the MOSIX Direct File System Access (DFSA), a provision that can improve the performance of cluster file systems by allowing a migrated process to directly access files in its current location. This capability, when combined with an appropriate file system, could substantially increase the I/O performance and reduce the network congestion by migrating an I/O intensive process to a file server rather than the traditional way of bringing the file's data to the process. DFSA is suitable for clusters that manage a pool of shared disks among multiple machines. With DFSA, it is possible to migrate parallel processes from a client node to file servers for parallel access to different files. Any consistent file system can be adjusted to work with DFSA. To test its performance, we developed the MOSIX File-System (MFS) which allows consistent parallel operations on different files. The paper describes DFSA and presents the performance of MFS with and without DFSA.  相似文献   

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