Literature databases

With the increasing number of publications on block copolymer micelles (a database literature search with these three associated keywords already gives more than 500 references), an exhaustive description of all previous works would not be possible in the framework of the present review. This contribution has rather as its purpose giving a general overview about block copolymer micelles for the nonspecialist and will therefore try to answer such practical questions as how does one prepare block copolymer micelles How does one characterize them What are the different types of structures that can be formed How can we predict them How does one tune the morphology of these micelles These basic questions and the corresponding answers will be illustrated by selected examples. Then, we will focus on the new directions that are currently implemented in this field. 

Value/origin of model parameters Estimated based on data available Estimated using combined datasets or taken from different sources (e.g. databases, literature, own experiments)... 

How Accurate is the Sequence This question is poorly documented in the database literature, but the assumption that the submitted sequence is as accurate as possible usually means at least two-pass coverage (in opposite orientations) on the whole submitted sequence. Equally important is the verification of the final submitted sequence. It should be free of vector contamination (this can be verified with a BLASTN search against the VecScreen database see Chapter 8 and later in this... 

Most database users do not know how the data are organized in a database system (DBS) they depend solely on the application programs. This is sufficient for most database searches where users can receive large amounts of results quickly and easily, e.g., on literature or other information. Nevertheless, a basic knowledge on where and how to find deeper or more detailed information is quite useful. Due to their complex nature, comprehensive searches (e.g., for processes or patents) are not recommended for beginners. However, most local (in-house), online, and CD-ROM databases provide extensive tutorials and help functions that are specific to the database, and that give a substantial introduction into database searching. 

The user is often more interested in the contents than in the technical organization of databases. The wide variety of data allows the classification of databases in chemistry into literature, factual (alphanumeric), and structural types (Figure 5-10) [12, 13). 

Medline covers primarily biomedical literature, containing more than 13 million citations (October, 2002) of articles from more than 4600 journals published since 1958 [18]. The database covers basic biomedical research, clinical sciences, dentistry, pharmacy, veterinary medicine, pre-clinical sciences, and life science. Medline, a subset of PubMed, is a bibliographic database produced by the US Nationcil Library of Medicine (NLM). The database is available free of charge via SciFinder Scholar or PubMed [19]. 

In the mid and late 1990s CAS developed the ChemPort module as a linked gateway to primary literature. The CAS online delivery clients arc able to move into CbemPort to display primaiy literature by presenting stored or dynamically generated URLs to ChemPort. Conversely, ChemPort will link a user to SciFinder to provide access to the CAS databases. 

Thus, if the user wants to look for literature including requested chemicals or reactions, it is possible to query the database by the first option Chemical Substance or Reaction , The compound can be entered as a query in three different ways drawing the chemical structure in a molecule editor (Chemical Structure) searching by names or identification number, such as the CAS Number (Structure Identifier) and searching by molecular formula (Figure 5-12). 

The reinaining five search topics (Research Topic, Author Name, Document Identifier, Company Namc/Organii ation, and Browse Table of Contents arc conducted in a similar fashion, with the input being the only difference between the criteria. Thus, in Research Topic" the entry can be any, or even several, keywords or phrases. In "Author Name", literature written by a specific author will be Found, including alternative spelling, Document Identifier" can also be entered directly in the query. Document identifiers arc CA abstract numbers, patent numbers, patent application numbers, or priority application numbers. The last two search topics (Company Name/Organi2ation, and Browse Table ofContents) allow one to search for literature from specific companies or to view the list of journals which are available in the database. 

Gmelin contains over 800 different chemical and physical property fields, and a detailed index of the original literature. Broad categories of data found in the database include ... 

The CAS Registry contains information on all the chemical compounds published in the literature since 1957. The sources of these 21 million compounds are 9000 international journals containing chemical information. The database includes CAS Registry Numbers, the CAS name (not conforming to the lUPAC convention) with synonyms, and molecular and structural formulas. The CAS provides a weekly update (see Section 5.4). 

Reaction databases contain a wealth of reactions performed in the laboratory and published in the literature, i.c., in contrast to the transform libraries of synthesis design programs they contain raw, uninterpreted reaction information. In Figure 10,3-41 a schematic representation of a reaction in a reaction database is given. 

Comparative QSAR is a field currently under development by several groups. Large databases of known QSAR and 3D QSAR results have been compiled. Such a database can be used for more than simply obtaining literature citations. The analysis of multiple results for the same or similar systems can yield a general understanding of the related chemistry as well as providing a good comparison of techniques. 

ANHBIOHCS - BETA-LACTAMS - CEPHALOSPORINS] (Vol 3) -patent database [PATENTS, LITERATURE] (Vol 18)... 

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