9,774 research outputs found
Automatic identification of relevant chemical compounds from patents
In commercial research and development projects, public disclosure of new chemical
compounds often takes place in patents. Only a small proportion of these compounds
are published in journals, usually a few years after the patent. Patent authorities make
available the patents but do not provide systematic continuous chemical annotations.
Content databases such as Elsevier’s Reaxys provide such services mostly based on
manual excerptions, which are time-consuming and costly. Automatic text-mining
approaches help overcome some of the limitations of the manual process. Different
text-mining approaches exist to extract chemical entities from patents. The majority
of them have been developed using sub-sections of patent documents and focus on
mentions of compounds. Less attention has been given to relevancy of a compound in a
patent. Relevancy of a compound to a patent is based on the patent’s context. A relevant
compound plays a major role within a patent. Identification of relevant compounds
reduces the size of the extracted data and improves the usefulness of patent resources
(e.g. supports identifying the main compounds). Annotators of databases like Reaxys
only annotate relevant compounds. In this study, we design an automated system
that extracts chemical entities from patents and classifies their relevance. The goldstandard set contained 18 789 chemical entity annotations. Of these, 10% were relevant
compounds, 88% were irrelevant and 2% were equivocal. Our compound recognition
system was based on proprietary tools. The performance (F-score) of the system on
compound recognition was 84% on the development set and 86% on the test set. The
relevancy classification system had an F-score of 86% on the development set and 82% on the test set. Our system can extract chemical compounds from patents and
classify their relevance with high performance. This enables the extension of the Reaxys
database by means of automation
Chemoinformatics Research at the University of Sheffield: A History and Citation Analysis
This paper reviews the work of the Chemoinformatics Research Group in the Department of Information Studies at the University of Sheffield, focusing particularly on the work carried out in the period 1985-2002. Four major research areas are discussed, these involving the development of methods for: substructure searching in databases of three-dimensional structures, including both rigid and flexible molecules; the representation and searching of the Markush structures that occur in chemical patents; similarity searching in databases of both two-dimensional and three-dimensional structures; and compound selection and the design of combinatorial libraries. An analysis of citations to 321 publications from the Group shows that it attracted a total of 3725 residual citations during the period 1980-2002. These citations appeared in 411 different journals, and involved 910 different citing organizations from 54 different countries, thus demonstrating the widespread impact of the Group's work
Comprehensive comparison of in silico MS/MS fragmentation tools of the CASMI contest: database boosting is needed to achieve 93% accuracy.
In mass spectrometry-based untargeted metabolomics, rarely more than 30% of the compounds are identified. Without the true identity of these molecules it is impossible to draw conclusions about the biological mechanisms, pathway relationships and provenance of compounds. The only way at present to address this discrepancy is to use in silico fragmentation software to identify unknown compounds by comparing and ranking theoretical MS/MS fragmentations from target structures to experimental tandem mass spectra (MS/MS). We compared the performance of four publicly available in silico fragmentation algorithms (MetFragCL, CFM-ID, MAGMa+ and MS-FINDER) that participated in the 2016 CASMI challenge. We found that optimizing the use of metadata, weighting factors and the manner of combining different tools eventually defined the ultimate outcomes of each method. We comprehensively analysed how outcomes of different tools could be combined and reached a final success rate of 93% for the training data, and 87% for the challenge data, using a combination of MAGMa+, CFM-ID and compound importance information along with MS/MS matching. Matching MS/MS spectra against the MS/MS libraries without using any in silico tool yielded 60% correct hits, showing that the use of in silico methods is still important
Representation and use of chemistry in the global electronic age.
We present an overview of the current state of public semantic chemistry and propose new approaches at a strategic and a detailed level. We show by example how a model for a Chemical Semantic Web can be constructed using machine-processed data and information from journal articles.This manuscript addresses questions of robotic access to data and its automatic re-use, including the role of Open Access archival of data. This is a pre-refereed preprint allowed by the publisher's (Royal Soc. Chemistry) Green policy. The author's preferred manuscript is an HTML hyperdocument with ca. 20 links to images, some of which are JPEgs and some of which are SVG (scalable vector graphics) including animations. There are also links to molecules in CML, for which the Jmol viewer is recommended. We susgeest that readers who wish to see the full glory of the manuscript, download the Zipped version and unpack on their machine. We also supply a PDF and DOC (Word) version which obviously cannot show the animations, but which may be the best palce to start, particularly for those more interested in the text
Technological change and international competitiveness: the case of Switzerland.
The paper presents the preliminary results of a research project on the relationship between technological and trade performance with a special focus on Switzerland. The analysis is based on two sources of data: a dataset based on patent applications by firms from major industrialized countries to the European Patent Office (EPO) and a data set on export flows of OECD countries (IMPEX database). For both datasets, the period of time is 1980-1992. The analysis is carried out both for the whole aggregate of manufacturing sectors (WS49) and for a subsample of high-tech sectors (HT49). In the first part of the paper, the relationship between trade and technological variables is analyzed descriptively using indexes of technological (RTA) and trade specialization (RCA). Then, in the second part of the paper, the relationship between trade and technological specialization is analyzed using econometric techniques and exploiting the information contained in the datasets along three dimensions: country, sector, time. Finally, sectoral and geographical patterns of innovative activities are analyzed for the case of Switzerland. The paper broadly confirms the existence of a positive relationship between technological and trade specialization. Such relationship is also stable over time. However, the relationship is not very strong and it holds differently across countries.
Information retrieval and text mining technologies for chemistry
Efficient access to chemical information contained in scientific literature, patents, technical reports, or the web is a pressing need shared by researchers and patent attorneys from different chemical disciplines. Retrieval of important chemical information in most cases starts with finding relevant documents for a particular chemical compound or family. Targeted retrieval of chemical documents is closely connected to the automatic recognition of chemical entities in the text, which commonly involves the extraction of the entire list of chemicals mentioned in a document, including any associated information. In this Review, we provide a comprehensive and in-depth description of fundamental concepts, technical implementations, and current technologies for meeting these information demands. A strong focus is placed on community challenges addressing systems performance, more particularly CHEMDNER and CHEMDNER patents tasks of BioCreative IV and V, respectively. Considering the growing interest in the construction of automatically annotated chemical knowledge bases that integrate chemical information and biological data, cheminformatics approaches for mapping the extracted chemical names into chemical structures and their subsequent annotation together with text mining applications for linking chemistry with biological information are also presented. Finally, future trends and current challenges are highlighted as a roadmap proposal for research in this emerging field.A.V. and M.K. acknowledge funding from the European
Community’s Horizon 2020 Program (project reference:
654021 - OpenMinted). M.K. additionally acknowledges the
Encomienda MINETAD-CNIO as part of the Plan for the
Advancement of Language Technology. O.R. and J.O. thank
the Foundation for Applied Medical Research (FIMA),
University of Navarra (Pamplona, Spain). This work was
partially funded by Consellería
de Cultura, Educación e Ordenación Universitaria (Xunta de Galicia), and FEDER (European Union), and the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic
funding of UID/BIO/04469/2013 unit and COMPETE 2020
(POCI-01-0145-FEDER-006684). We thank Iñigo Garciá -Yoldi
for useful feedback and discussions during the preparation of
the manuscript.info:eu-repo/semantics/publishedVersio
A survey of chemical information systems
A survey of the features, functions, and characteristics of a fairly wide variety of chemical information storage and retrieval systems currently in operation is given. The types of systems (together with an identification of the specific systems) addressed within this survey are as follows: patents and bibliographies (Derwent's Patent System; IFI Comprehensive Database; PULSAR); pharmacology and toxicology (Chemfile; PAGODE; CBF; HEEDA; NAPRALERT; MAACS); the chemical information system (CAS Chemical Registry System; SANSS; MSSS; CSEARCH; GINA; NMRLIT; CRYST; XTAL; PDSM; CAISF; RTECS Search System; AQUATOX; WDROP; OHMTADS; MLAB; Chemlab); spectra (OCETH; ASTM); crystals (CRYSRC); and physical properties (DETHERM). Summary characteristics and current trends in chemical information systems development are also examined
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