Quertle
Encyclopedia
Quertle is a semantic
search engine for life and chemical science literature and information. It covers a wide variety of information sources.
-based linguistics
to automatically extract subject–verb–object relationships asserted by the author(s) of each document. The identification of these assertions uses several methods including natural language processing
. For full-text documents, Quertle includes only the main content, not, for example, the references.
The subject–verb–object relationships are stored in a metadatabase
and the user's query is matched against that metadata
. This identifies documents based on meaning and context and generally provides fewer, but more relevant, hits than a traditional keyword search. Thus, Quertle is fundamentally different from search sites such as PubMed
. Nonetheless, Quertle does simultaneously search a keyword index to find documents based on inclusion of the search terms. These are presented on a separate tab in the results.
An ontology
covering genes, proteins, chemicals, diseases, cell types, and other life, chemical, and biomedical science nomenclature
is used to automatically search for all variants of a term in the user's query. For example, a search for "aspirin
" will find asserted relationships that mention "acetylsalicylic acid". The ontology also is used to find members of a class of entities, such as "neurotransmitter
s".
, full-text articles from BioMed Central
and PubMed Central
(open access subset), NIH
grants, the US National Library of Medicine
TOXNET database, and biomedical news.
Semantics
Semantics is the study of meaning. It focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for, their denotata....
search engine for life and chemical science literature and information. It covers a wide variety of information sources.
How Quertle Works
Quertle uses semanticSemantics
Semantics is the study of meaning. It focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for, their denotata....
-based linguistics
Linguistics
Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....
to automatically extract subject–verb–object relationships asserted by the author(s) of each document. The identification of these assertions uses several methods including natural language processing
Natural language processing
Natural language processing is a field of computer science and linguistics concerned with the interactions between computers and human languages; it began as a branch of artificial intelligence....
. For full-text documents, Quertle includes only the main content, not, for example, the references.
The subject–verb–object relationships are stored in a metadatabase
Metadatabase
Metadatabase is a database model for metadata management, global query of independent databases, and distributed data processing.This term is an addition to the dictionary. Originally, metadata is only a common term referring simply to "data about data", such as tags, keywords, and markup headers...
and the user's query is matched against that metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
. This identifies documents based on meaning and context and generally provides fewer, but more relevant, hits than a traditional keyword search. Thus, Quertle is fundamentally different from search sites such as PubMed
PubMed
PubMed is a free database accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintains the database as part of the Entrez information retrieval system...
. Nonetheless, Quertle does simultaneously search a keyword index to find documents based on inclusion of the search terms. These are presented on a separate tab in the results.
An ontology
Ontology
Ontology is the philosophical study of the nature of being, existence or reality as such, as well as the basic categories of being and their relations...
covering genes, proteins, chemicals, diseases, cell types, and other life, chemical, and biomedical science nomenclature
Nomenclature
Nomenclature is a term that applies to either a list of names or terms, or to the system of principles, procedures and terms related to naming - which is the assigning of a word or phrase to a particular object or property...
is used to automatically search for all variants of a term in the user's query. For example, a search for "aspirin
Aspirin
Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...
" will find asserted relationships that mention "acetylsalicylic acid". The ontology also is used to find members of a class of entities, such as "neurotransmitter
Neurotransmitter
Neurotransmitters are endogenous chemicals that transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles clustered beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to...
s".
Content
Quertle indexes MEDLINEMEDLINE
MEDLINE is a bibliographic database of life sciences and biomedical information. It includes bibliographic information for articles from academic journals covering medicine, nursing, pharmacy, dentistry, veterinary medicine, and health care...
, full-text articles from BioMed Central
BioMed Central
BioMed Central is a UK-based, for-profit scientific publisher specialising in open access journal publication. BMC, and its sister companies Chemistry Central and PhysMath Central, publish over 200 scientific journals. Most BMC journals are now published only online. BMC describes itself as the...
and PubMed Central
PubMed Central
PubMed Central is a free digital database of full-text scientific literature in biomedical and life sciences. It grew from the online Entrez PubMed biomedical literature search system. PubMed Central was developed by the U.S. National Library of Medicine as an online archive of biomedical journal...
(open access subset), NIH
National Institutes of Health
The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...
grants, the US National Library of Medicine
United States National Library of Medicine
The United States National Library of Medicine , operated by the United States federal government, is the world's largest medical library. Located in Bethesda, Maryland, the NLM is a division of the National Institutes of Health...
TOXNET database, and biomedical news.