Databases Specialised

Recapitulating, large search engines are useful to obtain a fast ovemew of search terms. To get more detailed information one has to enter qualified, specialised portals or even utilize databases (see above). 

Since the first edition of this book, developments have continued in this area, particularly with respect to computerised databases as a source of detailed and reliable data for use in the pharmacoeconomic assessment of new drugs. The creation of specialised databases, such as IT IV Insight, which contains the detailed clinical records of about 2500 patients who are either... 

HIV seropositive or have the disease AIDS, has been very successful and plans are being made to develop other specialised databases in diabetes, oncology, Alzheimer s, osteoporosis and other similar chronic diseases. 

The high-throughput production of data at each level of the combinatorial loop enforces an automated flow of data, which requires automated acquisition and retrieval. Since no database adapted to the specific case of heterogeneous catalysis is currently available (except those included in soft- and hardware packages provided by specialised companies, but at prices that academic groups cannot afford), the only solution was to develop an in-house database that fitted exactly the laboratory requirements. 

Accurate self-consistent thermochemical data for the copper chlorides up to 200°C are required, in order to improve solubility calculations and electrochemical modelling capabilities for Aspen Plus and OLI software. Experimental work has been initiated at the University of Guelph, Canada and UOIT to determine a comprehensive thermochemical database, for solubility limits of OMIT, and aqueous cupric chloride versus chloride concentration and temperature using UV-VIS spectroscopy (Suppiah, 2008). The chloride ion is obtained by adding LiCl OMIT. The conditions of tests are primarily 25-200°C, up to 20 bars. Specialised equipment for this task is needed to reach elevated temperatures and pressures, because cupric chloride is chemically aggressive, and because changes in the solution concentrations must be made precisely. A titanium test cell has been custom made, including a UV-VIS spectrometer with sapphire windows, HPLC pumps and an automated injection system. The data acquired will be combined with past literature data for the cuprous chloride system to develop a self-consistent database for the copper (I) and copper (II) chloride-water systems. 

The development of algorithms for the handling of chemical structures and data, and the application of artificial intelligence to property prediction, etc., led to the emergence of companies specialising in chemical software applications, now known as chem(o)informatics. Ideally such enterprises should couple with large dictionary databases. 

There are many methods used to produce ions in the MS ion source, with the electron impact (El) process being the most widely used. Databases containing standard 70 eV El spectra for over 140000 compounds are available. Chemical ionisation (Cl) and field ionisation (FI) have attracted a specialised interest. 

Depending on the instrument manufacturer a number of smaller specialised mass spectra databases are being made available, either as standard or as optional extras with the spectrometer data systems. A few of the more frequently found libraries are given below as well as collections of more unusual mass spectrometry techniques. Also included are a few references to data collection activities by some concerned organisations. 

One of the smaller databases commonly delivered as standard with many GC/MS spectrometers is the PMW or Pfleger/Maurer/Weber. This database of about 4300 spectra is also pubhshed in book form with the 4th part bringing the database up to some 6300 spectra [10]. This is a good collection for those specialising in, for example, clinical toxicology, pharmacology, environmental chemistry and food analysis. 

Note that many features of a chemical database system could not be reasonably duplicated with a commercial DBMS. One reason was that general DBMS s were designed to treat numbers, text, dates and money data types, but not abstract data types such as chemical structures. This allowed DBMS vendors to tune the performance of their product to the needs of the general business community, a vast market place, and to avoid specialisation in narrower markets such as the chemical/pharmaceutical industry. 

The data for the ECDIN databank are collected by specialised research institutions working under contract to the Commission. The contractors scan the published and unpublished literature and extract data for ECDIN. Information about the source for the individual data items is stored in the databank together with the extracted data. The data collection is supervised by a group of the Commission s scientific staff working at the Ispra Establishment of JRC. The ECDIN group in Ispra also takes care of the loading of the data into the database and of the general maintenance of the databank. 

Figure 12. Schematic View for Generation of a Specialised Database.

The main goal for the software system under development is to make available in machine-readable form all the information contained in Cheminform. In this way different kinds of indexes may be produced as well as data deaUng with selected parts of chemistry for specialised information services, either printed or on computer-readable media. But the most important fact is that the information in Cheminform contains all the data needed for a reaction database. 

Based on these formulated tasks, the system is divided into specialised, stand-alone blocks for solving each task (Fig. 4). Each block, in accordance with its function, possesses and uses the necessary databases that consist of dimensions, co-ordinates along the work axes and tolerances of... 

Structured alphanumeric data. These data types consist of mixed letters and numbers in a highly structured format of records and fields. Database programs accept these data types, including the specialised database programs used for specific purposes such as accident and incident recording. 

We will instead start with the most frequently observed nets, based on two surveys of the Cambridge Structural Database, [3,5] dubbed the default nets , [6] and then move on to a connectivity based approach. However, we will in general refrain from extensive discussion of hypothetical nets that have not been observed. Not because these are uninteresting, on the contrary they could be important synthetic targets, but because in principle there is an infinite number of these nets. We refer the reader to the growing literature specialising in this area [7-9] and to the RCSR database [4]. 

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