Tesauro PLOS
The "Subject Areas" panel on each article page displays a set of terms selected for that article based on its content. The Subject Areas belong to a thesaurus of over 10,000 terms initially built for us over the course of 2012 by Access Innovations, taking into account the controlled vocabulary of classification terms that had been in use in PLOS Editorial Manager. The entire corpus of PLOS articles was analysed to ensure that the thesaurus covers the research domain comprehensively.
Specific terms are associated with articles by Machine Aided Indexing (MAI) which identifies text strings in the articles and matches them to Subject Area terms from the thesaurus. The output ranks the matches in order of frequency of hits within the text of the article and the top eight terms are selected for display. Whereas previously the eight terms were presented in alphabetical order, we are introducing weightings to the Subject Area panel, such that the order of Subject Areas will reflect the frequency of hits in the MAI process. This new presentation will be introduced progressively, beginning with the main Article tab.
The MAI process uses a Rulebase to guide Subject Area selection. Whereas identifying a phrase such as "Retinitis pigmentosa" is relatively straightforward for software, the issue is more complex for a word such as "Sodium" where the relevant Subject Area might be "Voltage-gated sodium channels", any of several sodium compounds or even just "Sodium" the element. The rule for terms such as "Sodium" are therefore compound and include conditional statements to disambiguate these different contexts. While the vast majority of terms are effectively indexed there remain ambiguities for some terms and part of our work is to continue to identify these cases and modify the Rulebase accordingly.
The Subject Area terms are related to each other with a system of broader/narrower term relationships. The thesaurus structure is a polyhierarchy, so for example the Subject Area "White blood cells" has two broader terms "Blood cells" and "Immune cells". At its deepest the hierarchy is ten tiers deep, with all terms tracking back to one or more of the top tier Subject Areas, such as "Biology and life sciences" or "Social sciences".
The Subject Area terms can be used to access PLOS articles via Advanced Search. The MAI Rulebase accommodates synonyms, so a Subject-specific Search for "Highly active antiretroviral therapy" will retrieve articles based on MAI matches to "HAART" (a known synonym) as well as "Highly active antiretroviral therapy" in one step. Additionally, because we select the most frequently MAI-indexed Subject Areas for each article the Search returns articles where the Subject Area in question ranks highly enough to be included in the top eight MAI-retrieved terms, so is of relatively high significance, whereas a query term in an "All fields" search will return every article that contains even a single match to the query term.
The hierarchical nature of the thesaurus also enhances article retrieval in Search. Not only does Search retrieve all articles specifically indexed by MAI with the query Subject Area term in question, but it also retrieves all articles specifically indexed with any Subject Area term that sits deeper into the hierarchy than the query Subject Area term, but on the same broader/narrower term path. Thus, in the "White blood cells" example, queries for either "Blood cells" or "Immune cells" will return all articles indexed with "White blood cells".
The Subject Area terms on all article pages are hyperlinked and following the link returns a listing of all articles to which that Subject Area term applies. Subject Area terms can also be used as the basis for Saved Searches, RSS feeds and PLOS ONE customized Journal Alerts.
The content of the PLOS thesaurus and the Rulebase that governs the application of Subject Areas to the articles is constantly under review. We incorporate analysis of the Subject Area panel "feedback" clicks into this review process, and are always happy to receive specific input on Subject Area terms and their application by email. We update the thesaurus behind the PLOS sites several times each year.
Questions and comments about Subject Areas and the PLOS thesaurus can be sent to subjectareas@plos.org.
Contexto
por
PLOS
Total de términos
14734
Términos con la letra L: 458
- Levodopa
- Lactococcus garvieae
- Leptospira interrogans
- Lactococcus lactis
- Listeria monocytogenes
- L929 cells
- La Nina USE El Niño-Southern Oscillation
- Labour and delivery USE Labor and delivery
- Labour economics USE Labor economics
- Labour history USE Labor history
- Labour market USE Labor markets
- Labour mobility USE Labor mobility
- Labour studies USE Labor studies
- laboratorios biológicos USE Biological laboratories
- Laboratory animals
- Laboratory equipment
- Laboratory medicine USE Pathology and laboratory medicine
- Laboratory tests
- Labrea fever
- Labrocytes USE Mast cells
- Labyrinth supporting cells
- Labyrinthodontia
- lac operon
- Lacazia loboi
- Laccases
- lactancia materna USE Breast feeding
- Lactates
- Lactation
- Lactic acid
- Lactic acid bacteria
- Lactic acidosis
- lactobacilus USE Lactobacillus
- Lactococcus
- Lactones
- Lactose
- Lacunar histiocytes USE Reed-Sternberg cells
- Lady Windermere syndrome
- lagunas USE Lagoons
- Lagovirus
- Laidlow's reticulum staining
- Lakes
- Laminar flow
- Laminectomy
- Laminin binding assay
- Lamins
- Lampreys
- Lancelets USE amfioxiformes
- Lancets
- Landmines
- Land use
- Landform dynamics
- Landform history
- Landforms
- Langerhans cells
- Langhans giant cells
- Language
- Language acquisition
- Language families
- Languages
- Lanthanum
- Lao people
- Laos
- Laparoscopic cholecystectomy
- Laparoscopic fulguration
- Laparoscopic nephrectomy
- Laparoscopy
- Laparotomy
- Large animals
- Large cell lung carcinoma
- Large-insert cloning
- Long-non-coding RNAs USE Long non-coding RNAs
- Large intestine
- Large mononuclear leukocytes USE Monocytes
- Larvae
- Larva migrans
- Larva migrans profundus USE Gnathostomiasis
- Larval metamorphosis USE Insect metamorphosis
- Larvicides
- Laryngectomy
- Laryngology
- Larynx
- Lasagna cells
- Laser beams
- Laser diodes USE Diode lasers
- LASIK
- Laser microsurgery
- Laser resurfacing
- LSCM USE Confocal laser microscopy
- láseres de argón USE Argon lasers
- Lasers
- Lassa fever
- Lassa virus
- Late expression factor
- Late phase III clinical trial
- Latent heat
- Lateral gene transfer USE Horizontal gene transfer
- Lateral roots
- Latex
- Latin-Americans USE Latin Americans
- Latitude
- latón USE Brass
- Latvia
- Latvians
- Laurasia
- Law and legal sciences
- Law enforcement
- Law of large numbers
- Law of the single price USE Law of one price
- Lawrencium
- LBW USE peso al nacer
- Liquid chromatography/tandem mass spectrometry USE Liquid chromatography-tandem mass spectrometry
- Liquid chromatography/mass spectrometry USE Liquid chromatography-mass spectrometry
- Linear discriminant analysis
- Le chatelier-braun principle USE Chemical equilibrium
- Leaching techniques
- Lead (element)
- Lead alloys
- Leadership training
- Leading edges
- Leaves
- Leaf development
- Leaf veins
- Learning
- Learning and memory
- Learning curves
- Learning disabilities
- Least-cost location
- Leather
- Lebanon
- Leber hereditary optic neuropathy
- leche humana
- Lecithin
- Lectin chromatography USE Lectin affinity chromatography
- Lectin affinity electrophoresis
- Lectins
- Lectures
- Light-emitting diodes
- Leeches
- Left hemisphere
- Legionella
- Legionella pneumophila
- Legionnaires' disease USE Legionellosis
- Legislation
- Legs
- Leguminosae USE Fabaceae
- Legumes
- Leigh syndrome
- Leiomyoma cells
- Leiomyosarcoma
- Leishmania
- Leishmania donovani
- Leishmania infantum
- Leishmania major
- Leishmaniasis
- Lemierre's syndrome
- Lemon trees
- Lemons
- Lemurs
- lenguaje ensamblador USE Assembly languages
- lenguas dinámicas USE Dynamic languages
- Lens (anatomy)
- Lens disorders
- Lenticels
- Lentivirus
- Leopards
- Leopardus pardalis USE Ocelots
- Lepidoptera USE Moths and butterflies
- Lepospondyli
- Leprosy
- Leptin
- Leptin signal transduction
- Leptons
- Leptospira
- Leptospirillum
- Leptospirosis
- Lesbians USE Homosexuals
- Lesch-Nyhan syndrome
- Lesions
- Lesotho
- Lethality (bacteriology)
- Lettuce
- leucemia linfoide aguda USE Acute lymphoblastic leukemia
- leucemia mieloide aguda USE Acute myeloid leukemia
- Leucine
- Leukocytes USE White blood cells
- Leukapheresis
- Leukemia cells
- Leukemias
- Leukocyte adhesion
- Leukocyte signaling
- Leukocytosis
- Leukotriene
- Lévy random variables
- Lewy bodies
- Lexical decision tasks
- Lexical semantics
- Lexicography
- Lexicons
- ley administrativa USE Administrative law
- Leydig cells
- Liberia
- Librarians
- Libraries
- Library science
- Library screening
- Libya
- Louse USE Lice
- Lichenology
- Liechtenstein
- Lifecourse epidemiology
- Life cycles
- Life expectancy
- Life support (space travel)
- Lifestyle causes of cancer
- Lift irrigation
- Ligaments
- Ligamenvirales
- Ligand characterization
- Ligand-gated ion channels
- Ligases
- Ligation assay
- Ligation-mediated polymerase chain reaction
- Light
- Light microscopy
- Light pulses
- Light scattering
- Light-gated ion channels
- LSFM USE Light-sheet fluorescence microscopy
- Lightning
- Lignin
- Lily
- Lima beans
- Limb buds
- Limb development
- Limb reduction defects
- Limb regeneration
- Limbic system
- Limbs (anatomy)
- Limestone
- Limited-fluctuation method
- Limited systemic sclerosis USE Scleroderma
- Limnetic ecology USE Freshwater ecology
- Limnetic ecosystems
- Limnogeology
- Limnology
- limpieza con benceno USE Benzene clearing
- Limulus
- Linear algebra
- Linear animals USE Inbred strains
- Linear filters
- Linear programming
- Linear quadratic estimation USE Kalman filter
- Linear regression analysis
- Linear spaces USE Vector spaces
- Lineweaver-Burke plot
- linfocitos B
- linfoma linfocítico crónico de células B USE B-cell chronic lymphocytic lymphoma
- linfoma ocular USE Ocular lymphoma
- Linguistic anthropology
- Linguistic geography
- Linguistic morphology
- Linguistics
- Linkage analysis
- Linkage disequilibrium
- Linkage mapping
- Linker insertion mutagenesis
- Linker-scanning mutagenesis
- Linoleic acid
- lionización USE X chromosome inactivation
- Lions
- Lipases
- Lipid aggregates
- Lipid analysis
- Lipid bilayer
- Lipid bilayer fusion USE Membrane fusion
- Lipid hormones
- Lipid inclusions
- Lipid mediators
- Lipid metabolism
- Lipid peroxidation
- Lipid profiles
- Lipid-protein interactions USE Protein-lipid interactions
- Lipid signaling
- Lipid structure
- Lipids
- Lipocytes USE adipocitos
- Lipodystrophy
- Liposome-mediated transfection
- Lipogenesis
- Lipoic acids
- Lipolysis
- Lipophilia
- Lipoplasty
- Lipopolysaccharide USE Endotoxins
- Lipoprotein metabolism
- Lipoprotein receptors
- Lipoprotein secretion
- Lipoprotein structure
- Lipoproteins
- Liposarcoma
- Liposome delivery
- Liposome synthesis
- Liposomes
- Liposuction
- Lipoylation
- Lips
- Liquid chromatography
- Liquid-liquid extraction
- Liquid nitrogen
- Liquid nitrogen freeze drying USE Cryopreservation
- Liquid scintillation counting
- Liquid-state dynamics
- líquido amniótico
- líquidos corporales
- Liquids
- Lissamphibia
- Listeria
- Listeriosis
- Literacy
- Lithic technology
- Lithium
- Lithium chloride
- Lithofacies
- Lithosphere
- Lithostratigraphy
- Lithuania
- Lithuanians
- Live-cell imaging USE In vivo imaging
- Liver
- Liver and spleen scan
- Liver cancer USE Hepatocellular carcinoma
- Liver development
- Liver disease and pregnancy
- Liver diseases
- Liver fibrosis
- Liver function tests
- Liver resection USE Hepatic resection
- Liver rot USE Fascioliasis
- Liver transplantation
- Livermorium
- Livestock
- Livestock treatment USE Livestock care
- Living-related liver transplantation
- Lizards
- Loa loa
- lobectomía temporal anterior USE Anterior temporal lobectomy
- Lobectomy
- Lobstein syndrome USE Osteogenesis imperfecta
- Lobsters
- lóbulo occipital USE Occipital lobe
- Local anesthesia USE Local and regional anesthesia
- Local bifurcations USE Bifurcation theory
- Local government
- Locked nucleic acids
- Locked-in syndrome
- Lockjaw
- locomoción biológica USE Biological locomotion
- Locomotion on the water surface
- Locomotor system USE Musculoskeletal system
- Locus coeruleus
- Locus control region
- Locusts
- Loess
- Log dose-response method
- Logic gates USE Logic circuits
- Logopedics USE Speech-language pathology
- Loiasis
- Lolium USE Ryegrass
- London dispersion forces
- Long-term care
- Longterm potentiation USE Long-term potentiation
- Longtailed macaque USE Macaca fascicularis
- Long-term memory
- Longitude
- Longitudinal studies
- Lotus
- Lou Gehrig's disease USE Amyotrophic lateral sclerosis
- Loudspeakers
- Louis-bar syndrome USE Ataxia-telangiectasia
- Louisiana
- Lower back pain
- Low blood pressure USE Hypotension
- Low density
- Low-dose adrenocorticotropic hormone stimulation test USE Low dose ACTH stimulation test
- Low-temperature phenomena
- LUV USE Low ultraviolet
- Low-voltage transmission electron microscopy USE Low voltage transmission electron microscopy
- Lower respiratory tract infections
- Lowry assay USE Colorimetric protein concentration assays
- Lubrication
- Lucerne USE alfalfa
- Lucifer Yellow staining
- Luciferase
- Luciferase assay
- Luciferin
- Lucite USE Plexiglas
- Ludwigs angina USE Ludwig's angina
- Lujo virus
- Lumbar plexus block
- Lumbar vertebrae
- Luminance
- Luminescence
- Luminescent proteins
- Lumpectomy
- Lundayeh USE Lun people
- luna terrestre USE Earth's moon
- Lunar exploration
- Lung and intrathoracic tumors
- Lung development
- Lung resection
- Lung scan USE Pulmonary imaging
- Lung transplantation
- Lung volume reduction surgery
- Lungfish
- Lungs
- Lupinus
- Lupus erythematosus
- Lupus nephritis
- Lutein cells
- Luteinizing hormone
- Lutetium
- Lutz-Splendore-de Almeida disease USE Paracoccidioidomycosis
- Luxembourg
- luz diurna USE Daylight
- Lyases
- Lyme disease
- Lymph
- Lymph node dissection
- Lymph nodes
- Lymphadenectomy
- Lymphatic philariasis USE Lymphatic filariasis
- Lymphatic mapping
- Lymphatic system
- Lymphedema
- Lymphoblastic leukemia
- Lymphocyte activation
- Lymphocyte proliferation
- Lymphocytes
- Lymphocytic choriomeningitis
- Lymphocytic choriomeningitis virus
- Lymphocytic leukemia
- Lymphopenia
- Lymphoid follicles
- Lymphoid organ development
- Lymphoid organs
- Lymphoid tissue
- Lymphoma cells
- Lymphomas
- Lymphomas of the head and neck
- Lymphoscintigraphy
- Lyophilization
- Lysine
- Lysine Sepharose chromatography USE Lysine chromatography
- Lysis (medicine)
- Lysogeny
- Lysosomes
- Lyssavirus
- Lytic cycle