1,097 research outputs found

    Fusing Data with Correlations

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    Many applications rely on Web data and extraction systems to accomplish knowledge-driven tasks. Web information is not curated, so many sources provide inaccurate, or conflicting information. Moreover, extraction systems introduce additional noise to the data. We wish to automatically distinguish correct data and erroneous data for creating a cleaner set of integrated data. Previous work has shown that a na\"ive voting strategy that trusts data provided by the majority or at least a certain number of sources may not work well in the presence of copying between the sources. However, correlation between sources can be much broader than copying: sources may provide data from complementary domains (\emph{negative correlation}), extractors may focus on different types of information (\emph{negative correlation}), and extractors may apply common rules in extraction (\emph{positive correlation, without copying}). In this paper we present novel techniques modeling correlations between sources and applying it in truth finding.Comment: Sigmod'201

    Aggregation Of Chlorophyll a Probed By Resonance Light Scattering Spectroscopy

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    We report the resonance light scattering (RLS) spectra of chlorophyll a aggregated in a 9:1 solution of formamide and pH 6.8 phosphate buffer. The aggregate formed after 2 h of mixing, referred to as Chl(469), shows a strong scattering feature at 469 nm (Soret band) and a much weaker feature at 699 nm (Q(y) band). A kinetic investigation confirmed that the aggregation process is cooperative, and also detected one intermediate (Chl(458)) with a strong RLS spectrum but only a weak CD spectrum. We propose that aggregation proceeds via at least three steps: 1) formation of a nucleating species, probably a dimer of chlorophylls; 2) formation of large aggregates with little or no secondary structure (e.g., Chl(458)); and 3) conformational change to form helical aggregate (Chl(469))

    Krooninen väsymysoireyhtymä : Etiologia, diagnostiikka, hoito sekä kuntoutusinterventiot

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    Tämän kroonisen väsymysoireyhtymän (KVO) diagnostiikkaa, etiologiaa ja hoitokeinojen vaikuttavuutta koskevan selvityksen menetelminä ovat systemaattinen kirjallisuuskatsaus ja kysely. Aiheen laajuuden vuoksi liikkeelle lähdettiin julkaistuista systemaattisista kirjallisuuskatsauksista, ja näistä saatavaa tietoa täydennettiin uusilla alkuperäistutkimuksilla. Katsausten ja hoitotutkimusten laatu arvioitiin ja näytönaste arvioitiin lopputulosmuuttujittain. Suomen hoitokäytännöistä haettiin lisätietoa KVO-potilaille sekä heitä hoitaville lääkäreille suunnatulla kyselyllä. Työ on tehty elokuun 2015 ja marraskuun 2016 välisenä aikana. Kroonisen väsymysoireyhtymän riskitekijöitä ovat traumaattiset kokemukset, aiempi masennus, yliaktiivinen elämäntapa ja täydellisyyden tavoittelu mutta toisaalta myös passiivisuus tai liikunnan välttely. Immuunijärjestelmä, neuroendokriininen järjestelmä ja autonominen hermosto ovat osallisia oireyhtymän patofysiologiassa. Pitkäkestoisella stressillä näyttää olevan tärkeä välittävä rooli. Kroonisen väsymysoireyhtymän diagnostiikassa oleellista on muiden väsymystä aiheuttavien, mahdollisesti henkeä uhkaavien, sairauksien poissulku. Erotusdiagnostiikkaa tehdään myös muiden väsymyksenä ilmenevien oireyhtymien tunnistamiseksi. Taudinmääritykseen on käytettävissä useita erilaisia kansainvälisiä diagnostisia kriteeristöjä. Kansallisia hoitosuosituksia tarvittaisiin yhdenmukaistamaan KVO-potilaiden nykyisellään kirjavaa diagnostiikkaa ja hoitoa Suomessa. Porrastettu fyysinen harjoittelu ja kognitiivis-behavioraalinen terapia ovat pitkään olleet ainoita hoitoja, joiden vaikuttavuudesta on kohtalaista näyttöä. Käytössä on myös lääkkeitä ja terapioita, joita on tutkittu vain hyvin vähän tai ei ollenkaan. Rintatolimodi ja rituksimabi ovat laskimonsisäisesti annosteltavia lääkeaineita, joilla näyttö KVO-potilaiden fyysisen toimintakyvyn parantajina on heikko. Sama pätee muun muassa suun kautta annosteltuun hydrokortisoniin, yrttilääkkeisiin ja ravintolisiin.peerReviewedVertaisarvioit

    A search strategy for occupational health intervention studies

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    Background: As a result of low numbers and diversity in study type, occupational health intervention studies are not easy to locate in electronic literature databases. Aim: To develop a search strategy that facilitates finding occupational health intervention studies in Medline, both for researchers and practitioners. Methods: A gold standard of articles was created by going through two whole volumes of 19 biomedical journals, both occupational health specialty and non-occupational health journals. Criteria for occupational health intervention studies were: evaluating an intervention with an occupational health outcome and a study design with a control group. Each journal was searched independently by two of the authors. Search terms were developed by asking specialists and counting word frequencies in gold standard articles. Results: Out of 11 022 articles published we found 149 occupational health intervention studies. The most sensitive single terms were work*[tw] (sensitivity 71%, specificity 88%) and effect*[tw] (sensitivity 75%, specificity 63%). The most sensitive string was (effect*[tw] OR control*[tw] OR evaluation*[tw] OR program*[tw]) AND (work*[tw] OR occupation*[tw] OR prevention*[tw] OR protect*[tw]) (sensitivity 89%, specificity 78%). The most specific single terms were "occupational health"[tw] (sensitivity 22%, specificity 98%) and effectiveness[tw] (sensitivity 22%, specificity 98%). The most specific string was (program[tw] OR "prevention and control"[sh]) AND (occupational[tw] OR worker*[tw]) (sensitivity 47%, specificity 98%). Conclusion: No single search terms are available that can locate occupational health intervention studies sufficiently. The authors' search strings have acceptable sensitivity and specificity to be used by researchers and practitioners respectively. Redefinition and elaboration of keywords in Medline could greatly facilitate the location of occupational health intervention studies

    Differentiation of Murine C2C12 Myoblasts Strongly Reduces the Effects of Myostatin on Intracellular Signaling

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    Alongside in vivo models, a simpler and more mechanistic approach is required to study the effects of myostatin on skeletal muscle because myostatin is an important negative regulator of muscle size. In this study, myostatin was administered to murine (C2C12) and human (CHQ) myoblasts and myotubes. Canonical and noncanonical signaling downstream to myostatin, related ligands, and their receptor were analyzed. The effects of tumorkines were analyzed after coculture of C2C12 and colon cancer-C26 cells. The effects of myostatin on canonical and noncanonical signaling were strongly reduced in C2C12 cells after differentiation. This may be explained by increased follistatin, an endogenous blocker of myostatin and altered expression of activin receptor ligands. In contrast, CHQ cells were equally responsive to myostatin, and follistatin remained unaltered. Both myostatin administration and the coculture stimulated pathways associated with inflammation, especially in C2C12 cells. In conclusion, the effects of myostatin on intracellular signaling may be cell line- or organism-specific, and C2C12 myotubes seem to be a nonoptimal in vitro model for investigating the effects of myostatin on canonical and noncanonical signaling in skeletal muscle. This may be due to altered expression of activin receptor ligands and their regulators during muscle cell differentiation.Peer reviewe

    Skill and added value of the MiKlip regional decadal prediction system for temperature over Europe

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    In recent years, several decadal prediction systems have been developed to provide multi-year predictions of the climate for the next 5–10 years. On the global scale, high decadal predictability has been identified for the North Atlantic sector, often extending over Europe. The first full regional hindcast ensemble, derived from dynamical downscaling, was produced within the German MiKlip project (‘decadal predictions’). The ensemble features annual starting dates from 1960 to 2017, with 10 decadal hindcasts per starting year. The global component of the prediction system uses the MPI-ESM-LR and the downscaling is performed with the regional climate model COSMO-CLM (CCLM). The present study focusses on a range of aspects dealing with the skill and added value of regional decadal temperature predictions over Europe. The results substantiate the added value of the regional hindcasts compared to the forcing global model as well as to un-initialized simulations. The results show that the hindcasts are skilful both for annual and seasonal means, and that the scores are comparable for different observational reference data sets. The predictive skill increases from earlier to more recent start-years. A recalibration of the simulation data generally improves the skill further, which can also be transferred to more user-relevant variables and extreme values like daily maximum temperatures and heating degree-days. These results provide evidence of the potential for the regional climate predictions to provide valuable climate information on the decadal time-scale to users
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