121 research outputs found

    Технология извлечения структур знаний с использованием аппарата расширенных семантических сетей

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    В статье рассматривается задача извлечения из текстов естественного языка структур знаний: информационных объектов («именованных сущностей»), их свойств, связей и фактов участия в действиях. Для этих целей разработан инструментарий: язык представления знаний (расширенные семантические сети – РСС) и их обработки (язык преобразования структур – ДЕКЛ). На этой основе созданы технологии, которые обладают следующими особенностями. Из текстов извлекаются не отдельные объекты (именованные сущности), а структуры знаний, представляющие связи объектов и их участие в действиях и событиях. Для извлечения структур знаний разработан уникальный семантико-ориентированный лингвистический процессор (ЛП), осуществляющий глубинный анализ текстов ЕЯ и выявляющий десятки типов объектов вместе с их структурами. Процессор ЛП управляется лингвистическими знаниями, представляющими собой декларативные структуры и обеспечивающие быструю настройку ЛП на предметную область и язык. Основой лингвистических знаний являются правила, обладающие высокой степенью избирательности при выявлении объектов («сущностей»), средствами устранения коллизий при их применении. Это позволяет минимизировать шумы и потери.У статті розглядається задача знайдення у текстах природної мови структур знань: інформаційних об’єктів («іменованих сутностей»), їх якостей зв’язків і фактів участі у діях. Для цих цілей розроблений інструментарій: мова представлення знань (розширені семантичні мережі – РСМ) та їх обробки (мова перетворення структур – ДЕКЛ). На цій основі створені технології, що мають наступні особливості. З тестів виділяються не окремі об’єкти (іменовані сутності), а структури знань, що представляють зв’язки об’єктів та їх участь у діях та подіях. З метою виділення структур знань розроблений винятковий семантико-орієнтований лінгвістичний процесор (ЛП), що здійснює глибинний аналіз текстів ЕЯ та виявляє десятки типів об’єктів разом з їх структурами. Процесор ЛП керується лінгвістичними знаннями, які представляють собою декларативні структури та забезпечують швидке настроювання ЛП на предметну сферу та мову. Основою лінгвістичних знань є правила, що мають високий ступінь вибірковості при виявленні об’єктів («сутностей»), засобами усунення колізій при їхньому використанні. Це дозволяє мінімізувати шуми та втрати.The paper is devoted to the extracting of knowledge structures from the natural language texts, i.e. information objects (“Named Entities”), their features, relationships, and participation in the actions and events. For this purpose, the language used for knowledge representation (extended semantic networks/ESN) and tools for processing (language for structure conversion LSC) are considered. On this base, the new technologies are proposed. These technologies have the following features: extraction from the texts of knowledge structures that represent the links of named entities and their participation in actions and events. For the knowledge extraction the unique semantic-oriented language processor (LP) are designed. Processor LP provides the deep analysis of NL-texts and revealing set of objects together with their structures. Processor LP is controlled by the linguistic knowledge, which are declarative structures (on ESN) and which provides the quick tuning of LP on subject area and language, both Russian and English

    A functional genomics approach reveals suggestive quantitative trait loci associated with combined TLR4 and BCP crystal-induced inflammation and osteoarthritis

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    Objective: Basic calcium phosphate (BCP) crystals can activate the NLRP3 inflammasome and are potentially involved in the pathogenesis of osteoarthritis (OA). In order to elucidate relevant inflammatory mechanisms in OA, we used a functional genomics approach to assess genetic variation influencing BCP crystal-induced cytokine production. Method: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy volunteers who were previously genotyped and stimulated with BCP crystals and/or lipopolysaccharide (LPS) after which cytokines release was assessed. Cytokine quantitative trait locus (cQTL) mapping was performed. For in vitro validation of the cQTL located in anoctamin 3 (ANO3), PBMCs were incubated with Tamoxifen and Benzbromarone prior to stimulation. Additionally, we performed co-localisation analysis of our top cQTLs with the most recent OA meta-analysis of genome-wide association studies (GWAS). Results: We observed that BCP crystals and LPS synergistically induce IL-1β in human PBMCs. cQTL analysis revealed several suggestive loci influencing cytokine release upon stimulation, among which are quantitative trait locus annotated to ANO3 and GLIS3. As functional validation, anoctamin inhibitors reduced IL-1β release in PBMCs after stimulation. Co-localisation analysis showed that the GLIS3 locus was shared between LPS/BCP crystal-induced IL-1β and genetic association with Knee OA. Conclusions: We identified and functionally validated a new locus, ANO3, associated with LPS/BCP crystal-induced inflammation in PBMCs. Moreover, the cQTL in the GLIS3 locus co-localises with the previously found locus associated with Knee OA, suggesting that this Knee OA locus might be explained through an inflammatory mechanism. These results form a basis for further exploration of inflammatory mechanisms in OA.</p

    Cerebral near-infrared spectroscopy monitoring versus treatment as usual for extremely preterm infants : a protocol for the SafeBoosC randomised clinical phase III trial

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    Background: Cerebral oxygenation monitoring may reduce the risk of death and neurologic complications in extremely preterm infants, but no such effects have yet been demonstrated in preterm infants in sufficiently powered randomised clinical trials. The objective of the SafeBoosC III trial is to investigate the benefits and harms of treatment based on near-infrared spectroscopy (NIRS) monitoring compared with treatment as usual for extremely preterm infants. Methods/design: SafeBoosC III is an investigator-initiated, multinational, randomised, pragmatic phase III clinical trial. Inclusion criteria will be infants born below 28 weeks postmenstrual age and parental informed consent (unless the site is using 'opt-out' or deferred consent). Exclusion criteria will be no parental informed consent (or if 'opt-out' is used, lack of a record that clinical staff have explained the trial and the 'opt-out' consent process to parents and/or a record of the parents' decision to opt-out in the infant's clinical file); decision not to provide full life support; and no possibility to initiate cerebral NIRS oximetry within 6 h after birth. Participants will be randomised 1:1 into either the experimental or control group. Participants in the experimental group will be monitored during the first 72 h of life with a cerebral NIRS oximeter. Cerebral hypoxia will be treated according to an evidence-based treatment guideline. Participants in the control group will not undergo cerebral oxygenation monitoring and will receive treatment as usual. Each participant will be followed up at 36 weeks postmenstrual age. The primary outcome will be a composite of either death or severe brain injury detected on any of the serial cranial ultrasound scans that are routinely performed in these infants up to 36 weeks postmenstrual age. Severe brain injury will be assessed by a person blinded to group allocation. To detect a 22% relative risk difference between the experimental and control group, we intend to randomise a cohort of 1600 infants. Discussion: Treatment guided by cerebral NIRS oximetry has the potential to decrease the risk of death or survival with severe brain injury in preterm infants. There is an urgent need to assess the clinical effects of NIRS monitoring among preterm neonates. Trial registration: ClinicalTrial.gov, NCT03770741. Registered 10 December 2018

    Supramolecular thermoplastics and thermoplastic elastomer materials with self-healing ability based on oligomeric charged triblock copolymers

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    Supramolecular polymeric materials constitute a unique class of materials held together by non-covalent interactions. These dynamic supramolecular interactions can provide unique properties such as a strong decrease in viscosity upon relatively mild heating, as well as self-healing ability. In this study we demonstrate the unique mechanical properties of phase-separated electrostatic supramolecular materials based on mixing of low molar mass, oligomeric, ABA-triblock copolyacrylates with oppositely charged outer blocks. In case of well-chosen mixtures and block lengths, the charged blocks are phase separated from the uncharged matrix in a hexagonally packed nanomorphology as observed by transmission electron microscopy. Thermal and mechanical analysis of the material shows that the charged sections have a T-g closely beyond room temperature, whereas the material shows an elastic response at temperatures far above this T-g ascribed to the electrostatic supramolecular interactions. A broad set of materials having systematic variations in triblock copolymer structures was used to provide insights in the mechanical properties and and self-healing ability in correlation with the nanomorphology of the materials

    Molecular evolution of the LNX gene family

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    <p>Abstract</p> <p>Background</p> <p>LNX (Ligand of Numb Protein-X) proteins typically contain an amino-terminal RING domain adjacent to either two or four PDZ domains - a domain architecture that is unique to the LNX family. LNX proteins function as E3 ubiquitin ligases and their domain organisation suggests that their ubiquitin ligase activity may be targeted to specific substrates or subcellular locations by PDZ domain-mediated interactions. Indeed, numerous interaction partners for LNX proteins have been identified, but the <it>in vivo </it>functions of most family members remain largely unclear.</p> <p>Results</p> <p>To gain insights into their function we examined the phylogenetic origins and evolution of the <it>LNX </it>gene family. We find that a <it>LNX1/LNX2</it>-like gene arose in an early metazoan lineage by gene duplication and fusion events that combined a RING domain with four PDZ domains. These PDZ domains are closely related to the four carboxy-terminal domains from multiple PDZ domain containing protein-1 (MUPP1). Duplication of the <it>LNX1/LNX2</it>-like gene and subsequent loss of PDZ domains appears to have generated a gene encoding a LNX3/LNX4-like protein, with just two PDZ domains. This protein has novel carboxy-terminal sequences that include a potential modular LNX3 homology domain. The two ancestral <it>LNX </it>genes are present in some, but not all, invertebrate lineages. They were, however, maintained in the vertebrate lineage, with further duplication events giving rise to five LNX family members in most mammals. In addition, we identify novel interactions of LNX1 and LNX2 with three known MUPP1 ligands using yeast two-hybrid asssays. This demonstrates conservation of binding specificity between LNX and MUPP1 PDZ domains.</p> <p>Conclusions</p> <p>The <it>LNX </it>gene family has an early metazoan origin with a LNX1/LNX2-like protein likely giving rise to a LNX3/LNX4-like protein through the loss of PDZ domains. The absence of LNX orthologs in some lineages indicates that LNX proteins are not essential in invertebrates. In contrast, the maintenance of both ancestral <it>LNX </it>genes in the vertebrate lineage suggests the acquisition of essential vertebrate specific functions. The revelation that the LNX PDZ domains are phylogenetically related to domains in MUPP1, and have common binding specificities, suggests that LNX and MUPP1 may have similarities in their cellular functions.</p

    Organization of multiprotein complexes at cell–cell junctions

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    The formation of stable cell–cell contacts is required for the generation of barrier-forming sheets of epithelial and endothelial cells. During various physiological processes like tissue development, wound healing or tumorigenesis, cellular junctions are reorganized to allow the release or the incorporation of individual cells. Cell–cell contact formation is regulated by multiprotein complexes which are localized at specific structures along the lateral cell junctions like the tight junctions and adherens junctions and which are targeted to these site through their association with cell adhesion molecules. Recent evidence indicates that several major protein complexes exist which have distinct functions during junction formation. However, this evidence also indicates that their composition is dynamic and subject to changes depending on the state of junction maturation. Thus, cell–cell contact formation and integrity is regulated by a complex network of protein complexes. Imbalancing this network by oncogenic proteins or pathogens results in barrier breakdown and eventually in cancer. Here, I will review the molecular organization of the major multiprotein complexes at junctions of epithelial cells and discuss their function in cell–cell contact formation and maintenance

    Tight junctions: from simple barriers to multifunctional molecular gates

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    Epithelia and endothelia separate different tissue compartments and protect multicellular organisms from the outside world. This requires the formation of tight junctions, selective gates that control paracellular diffusion of ions and solutes. Tight junctions also form the border between the apical and basolateral plasma-membrane domains and are linked to the machinery that controls apicobasal polarization. Additionally, signalling networks that guide diverse cell behaviours and functions are connected to tight junctions, transmitting information to and from the cytoskeleton, nucleus and different cell adhesion complexes. Recent advances have broadened our understanding of the molecular architecture and cellular functions of tight junctions

    Reinhardt domains and the Gleason problem

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    let A(V) be the uniform algebra consisting ofthe functions which are holomorphic on a domain V, and continuous up to its boundary, and let H(V)H^{\infty}(V) be the set of bounded holomorphic functions on V.Throughout this paper V will be a bounded Reinhardt domain in C^2 with C2C^{2}-boundary.We show that the maximal ideal (both in A(V) and H(V))H^{\infty}(V)), consisting of functions vanishingat p in V, is generated by the functions (z_1 - p_1), (z_2 - p_2), at first for the case that V is pseudoconvex, then without this condition

    League tables of breast cancer screening units: worst-case and best-case scenario ratings helped in exposing real differences between performance ratings.

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    Contains fulltext : 79989.pdf (publisher's version ) (Closed access)OBJECTIVES: Data on the performance of health boards, hospitals and medical specialists, etc., are being collected at various levels in the health-care system and are often presented as league tables. These tables ignore natural variation and/or confounders, and this introduces uncertainty about their interpretation. The purpose of this study was to devise and illustrate a method to expose the real difference between the ratings in league tables. METHODS: Two values per rating were added to the league tables: the best-case scenario and the worst-case scenario. True performance will lie somewhere between these two values. The method is illustrated using data from the Dutch breast cancer screening programme. RESULTS: By focusing on one performance indicator and one confounder, it was possible to show shifts in the rating order of breast cancer screening units and thus expose the uncertainty about the true performance of each screening unit. CONCLUSIONS: The worst-case and best-case scenario ratings demonstrated the uncertainty within the ratings of a league table. League tables should therefore only be used with great caution and after providing the public with sufficient information
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