1,313 research outputs found

    Hybrid Search: Effectively Combining Keywords and Semantic Searches

    Get PDF
    This paper describes hybrid search, a search method supporting both document and knowledge retrieval via the flexible combination of ontologybased search and keyword-based matching. Hybrid search smoothly copes with lack of semantic coverage of document content, which is one of the main limitations of current semantic search methods. In this paper we define hybrid search formally, discuss its compatibility with the current semantic trends and present a reference implementation: K-Search. We then show how the method outperforms both keyword-based search and pure semantic search in terms of precision and recall in a set of experiments performed on a collection of about 18.000 technical documents. Experiments carried out with professional users show that users understand the paradigm and consider it very powerful and reliable. K-Search has been ported to two applications released at Rolls-Royce plc for searching technical documentation about jet engines

    mGlu5-mediated signalling in developing astrocyte and the pathogenesis of autism spectrum disorders.

    Get PDF
    Astrocytes, the largest glial population in human and murine brains, are crucial to the regulation of synaptic connectivity. During the first three weeks of postnatal development, immature astrocytes express mGlu5 and expands several fold while undergoing a transition towards their mature phase. Although mGlu5-mediated signalling in astrocyte functions has been extensively studied in the last decades, whether this signalling is implicated in the mechanisms governing their development, as well as the effects of dysregulated astrocytic development on neurodevelopmental disorders, are still unclear. The aim of this review is to examine what is known about the mGlu5-mediated signalling in the developing astrocytes and its possible contribution to the pathophysiology of autism spectrum disorders

    Astrocytes and Microglia and Their Potential Link with Autism Spectrum Disorders.

    Get PDF
    The cellular mechanism(s) underlying autism spectrum disorders (ASDs) are not fully understood although it has been shown that various genetic and environmental factors contribute to their etiology. As increasing evidence indicates that astrocytes and microglial cells play a major role in synapse maturation and function, and there is evidence of deficits in glial cell functions in ASDs, one current hypothesis is that glial dysfunctions directly contribute to their pathophysiology. The aim of this review is to summarize microglia and astrocyte functions in synapse development and their contributions to ASDs

    Numerical simulation of 3D free surface flows in time dependent curvilinear coordinates

    Get PDF
    We propose a three dimensional non-hydrostatic shock-capturing numerical model for the simulation of wave propagation, transformation and breaking, which is based on an original integral formulation of the contravariant Navier-Stokes equations, devoid of Christoffel symbols, in general time-dependent curvilinear coordinates

    Colloidal CuFeS2 Nanocrystals: Intermediate Fe d-Band Leads to High Photothermal Conversion Efficiency

    Get PDF
    We describe the colloidal hot-injection synthesis of phase-pure nanocrystals (NCs) of a highly abundant mineral, chalcopyrite (CuFeS2). Absorption bands centered at around 480 and 950 nm, spanning almost the entire visible and near infrared regions, encompass their optical extinction characteristics. These peaks are ascribable to electronic transitions from the valence band (VB) to the empty intermediate band (IB), located in the fundamental gap and mainly composed of Fe 3d orbitals. Laser-irradiation (at 808 nm) of an aqueous suspension of CuFeS2 NCs exhibited significant heating, with a photothermal conversion efficiency of 49%. Such efficient heating is ascribable to the carrier relaxation within the broad IB band (owing to the indirect VB-IB gap), as corroborated by transient absorption measurements. The intense absorption and high photothermal transduction efficiency (PTE) of these NCs in the so-called biological window (650-900 nm) makes them suitable for photothermal therapy as demonstrated by tumor cell annihilation upon laser irradiation. The otherwise harmless nature of these NCs in dark conditions was confirmed by in vitro toxicity tests on two different cell lines. The presence of the deep Fe levels constituting the IB is the origin of such enhanced PTE, which can be used to design other high performing NC photothermal agents.Comment: 12 pages, Chemistry of Materials, 31-May-201

    Tratamiento quirúrgico vs terapia periodontal básica: estudios longitudinales en periodoncia clínica

    Get PDF
    Las enfermedades periodontales son unas graves infecciones bacterianas que destruyen las fibras de inserción y el hueso de soporte que mantienen los dientes en la boca. Sin tratar, esta enfermedad puede llevar a la pérdida dental (Medical Dictionary). Los estudios longitudinales han centrado su atención hacia la periodontitis crónica. Se ha documentado el decisivo papel de la placa bacteriana en la iniciación y en el mantenimiento de la gingivitis, y que, los efectos dañinos sobre los tejidos y la gravedad de estos efectos están regulados por una compleja interacción entre el parásito y huésped. El tratamiento de la lesión periodontal cumple, para el tratamiento periodontal básico, con el propósito de eliminar y prevenir la recurrencia de los depósitos bacterianos localizados en las superficies dentarias supragingivales y subgingivales y, para el tratamiento quirúrgico con el objetivo de crear acceso para el desbridamiento profesional correcto de las superficies radiculares infectadas y establecer una morfología gingival adecuada que facilite el autocontrol de la placa por parte del paciente. Diferentes técnicas se han utilizado para alcanzar el objetivo de mejorar el pronóstico de los dientes a largo plazo. Desafortunadamente no son muchos los estudios que consiguen demostrar la efectividad de las técnicas utilizadas, con una evolución a lo largo del tiempo dejando entonces algunas incertidumbres. Periodontal diseases are bacterial infections that destroy the attachment fibres and supporting bone that hold the teeth in the mouth. Left untreated, these diseases can lead to tooth loss (Medical Dictionary). Longitudinal studies centred their attention on chronic periodontitis. It has been documented the decisive role played by microbiological plaque in the initiation of gingivitis and that, the harmful effect on the tissues and its severity, are controlled by the complex host-parasite interaction. Treatment of periodontal lesion can be carried out either by non-surgical treatment, to eliminate and prevent the recurrence of bacterial deposits, or by surgical treatment, to create access for professional debridment of infected root surface and establish adequate gingival morphology to facilitate self plaque control. Different techniques are used to achieve the objective to improve teeth long term prognosis. Unfortunately no many studies have been able to demonstrate the effectiveness of the used technique in a long term intervals leaving unclear some questions

    Lipomatous hypertrophy: an accidental finding in heart

    Get PDF
    Lipomatous hypertrophy is an uncommon benign lesion of the atrium, generally asymptomatic, characterized by unencapsulated accumulation of adipose tissue entrapping cardiomyocytes. This pathology generally remains unnoticed and often emerges as an occasional finding. Here, we report two cases from our hospital including a review of the available literature

    A metanalysis on cabozantinib and bone metastases: True story or commercial gimmick?

    Get PDF
    Is it true that cabozantinib should be the preferred option treating patients with bone metastases? Are there any reliable comparisons between this drug and other standard options in this subgroup? To address the issue, we performed a systematic review and metanalysis of randomized trials with cabozantinib, to assess its effectiveness, in terms of overall survival, according to the presence of bone metastases. We included (a) randomized controlled trials; (b) any solid tumors and therapeutic line; and (c) overall survival data available according to the site of disease. Cabozantinib improved overall survival both for the group with bone metastases, with risk of death decreased by 53% (hazard ratio, 0.47; 95% confidence interval, 0.26–0.87; P=0.02) and for the group without bone metastases, decreasing the risk of death by 44% (hazard ratio, 0.56; 95% confidence interval, 0.40–0.79; P=0.001) over the standard of care. The difference was not significantly different between the two groups. Despite cabozantinib can be undoubtedly listed as a good therapeutic option for cancer patients with bone metastases, it seems that its preclinical profile against bone remodeling does not translate into an actual clinical relevance, preventing from considering the presence of bone metastases as principal criterion for the choice of this drug

    Active dumbbells: dynamics and morphology in the coexisting region

    Full text link
    With the help of molecular dynamics simulations we study an ensemble of active dumbbells in purely repulsive interaction. We derive the phase diagram in the density-activity plane and we characterise the various phases with liquid, hexatic and solid character. The analysis of the structural and dynamical properties, such as enstrophy, mean square displacement, polarisation, and correlation functions, shows the continuous character of liquid and hexatic phases in the coexisting region when the activity is increased starting from the passive limit
    corecore