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Evaluation and comparison of satellite precipitation estimates with reference to a local area in the Mediterranean Sea
Precipitation is one of the major variables for many applications and disciplines related to water resources and the geophysical Earth system. Satellite retrieval systems, rain-gauge networks, and radar systems are complementary to each other in terms of their coverage and capability of monitoring precipitation. Satellite-rainfall estimate systems produce data with global coverage that can provide information in areas for which data from other sources are unavailable. Without referring to ground measurements, satellite-based estimates can be biased and, although some gauge-adjusted satellite-precipitation products have been already developed, an effective way of integrating multi-sources of precipitation information is still a challenge.In this study, a specific area, the Sicilia Island (Italy), has been selected for the evaluation of satellite-precipitation products based on rain-gauge data. This island is located in the Mediterranean Sea, with a particular climatology and morphology, which can be considered an interesting test site for satellite-precipitation products in the European mid-latitude area. Four satellite products (CMORPH, PERSIANN, PERSIANN-CCS, and TMPA-RT) and two GPCP-adjusted products (TMPA and PERSIANN Adjusted) have been selected. Evaluation and comparison of selected products is performed with reference to data provided by the rain-gauge network of the Island Sicilia and by using statistical and graphical tools. Particular attention is paid to bias issues shown both by only-satellite and adjusted products. In order to investigate the current and potential possibilities of improving estimates by means of adjustment procedures using GPCC ground precipitation, the data have been retrieved separately and compared directly with the reference rain-gauge network data set of the study area.Results show that bias is still considerable for all satellite products, then some considerations about larger area climatology, PMW-retrieval algorithms, and GPCC data are discussed to address this issue, along with the spatial and seasonal characterization of results. Š 2013 Elsevier B.V
Shear transfer in bolted side-plated reinforced concrete beams
Reinforced concrete (RC) beams strengthened with bolted steel plates on their vertical faces are known as bolted side-plated (BSP) beams. The behaviour and performance of BSP beams are controlled by the arrangement of the steel plates and the interfacial slips caused by the shear deformation of anchor bolts due to shear force transfer. In this study, a nonlinear finite element model validated by available experimental results has been used to investigate the shear stress transfer in BSP beams. The effects of loading arrangements and the stiffnesses of RC beams, steel plates and bolt connections were investigated in detail by a parametric study. The results of this study shed light on the basic understanding of the internal shear transfer mechanism between steel plates and RC beams. A new design approach is also provided to help structural engineers in the determination of the shear transfer profile and the critical bolt shear force in the design of BSP beams.postprin
Design of bolted side-plated reinforced-concrete beams with partial interaction
Existing reinforced-concrete (RC) beams can be effectively strengthened by anchoring steel plates to the side faces of the beams using bolts, which is known as the bolted side-plating (BSP) technique. Previous studies have found that the performance of BSP beams is primarily controlled by the degree of partial interaction at the steel-RC interface, which can be conveniently quantified by the strain and curvature factors. In this paper, a new simplified flexural design procedure for BSP beams taking into account partial interaction is presented. Some optimum ranges of strain and curvature factors are first introduced to the flexural design of BSP beams. By ensuring the flexural capacity of a BSP beam is higher than the design moment, the preliminary size of steel plates and the arrangement of bolts can be determined. Following this, the maximum design slips and minimum design strain and curvature factors are calculated and back-checked to ensure the target flexural capacity of the BSP beam has been achieved. An example is presented to illustrate the effectiveness of the optimised design method for BSP beams, considering the effect of partial interaction under realistic loading conditions.published_or_final_versio
Lowered Immune Cell Function in Liver Recipients Recovered From Posttransplant Lymphoproliferative Disease Who Developed Graft Tolerance
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Epidemiology of human parechovirus, Aichi virus and salivirus in fecal samples from hospitalized children with gastroenteritis in Hong Kong
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Lysosomal acidification dysfunction in microglia: an emerging pathogenic mechanism of neuroinflammation and neurodegeneration
Microglia are the resident innate immune cells in the brain with a major role in orchestrating immune responses. They also provide a frontline of host defense in the central nervous system (CNS) through their active phagocytic capability. Being a professional phagocyte, microglia participate in phagocytic and autophagic clearance of cellular waste and debris as well as toxic protein aggregates, which relies on optimal lysosomal acidification and function. Defective microglial lysosomal acidification leads to impaired phagocytic and autophagic functions which result in the perpetuation of neuroinflammation and progression of neurodegeneration. Reacidification of impaired lysosomes in microglia has been shown to reverse neurodegenerative pathology in Alzheimer's disease. In this review, we summarize key factors and mechanisms contributing to lysosomal acidification impairment and the associated phagocytic and autophagic dysfunction in microglia, and how these defects contribute to neuroinflammation and neurodegeneration. We further discuss techniques to monitor lysosomal pH and therapeutic agents that can reacidify impaired lysosomes in microglia under disease conditions. Finally, we propose future directions to investigate the role of microglial lysosomal acidification in lysosome-mitochondria crosstalk and in neuron-glia interaction for more comprehensive understanding of its broader CNS physiological and pathological implications
Cross-sections for heavy atmospheres: HâO continuum
Most of the exoplanets detected up to now transit in front of their host stars, allowing for the generation of transmission spectra; the study of exoplanet atmospheres relies heavily upon accurate analysis of these spectra. Recent discoveries mean that the study of atmospheric signals from low-mass, temperate worlds are becoming increasingly common. The observed transit depth in these planets is small and more difficult to analyze. Analysis of simulated transmission spectra for two small, temperate planets (GJ 1214 b and K2-18 b) is presented, giving evidence for significant differences in simulated transit depth when the water vapor continuum is accounted for when compared to models omitting it. These models use cross-sections from the CAVIAR lab experiment for the water self-continuum up to 10,000 cmâ1; these cross-sections exhibit an inverse relationship with temperature, hence lower-temperature atmospheres are the most significantly impacted. Including the water continuum strongly affects transit depths, increasing values by up to 60 ppm, with the differences for both planets being detectable with the future space missions Ariel and JWST. It is imperative that models of exoplanet spectra move toward adaptive cross-sections, increasingly optimized for H2O-rich atmospheres. This necessitates including absorption contribution from the water vapor continuum into atmospheric simulations
From caution to urgency: the evolution of HIV testing and counselling in Africa.
OBJECTIVE: To describe recent changes in policy on provider-initiated testing and counselling (PITC) for human immunodeficiency virus (HIV) infection in African countries and to investigate patients' experiences of and views about PITC. METHODS: A review of the published literature and of national HIV testing policies, strategic frameworks, plans and other relevant documents was carried out. FINDINGS: Of the African countries reviewed, 42 (79.2%) had adopted a PITC policy. Of the 42, all recommended PITC for the prevention of mother-to-child HIV transmission, 66.7% recommended it for tuberculosis clinics and patients, and 45.2% for sexually transmitted infection clinics. Moreover, 43.6% adopted PITC in 2005 or 2006. The literature search identified 11 studies on patients' experiences of and views about PITC in clinical settings in Africa. The clear majority regarded PITC as acceptable. However, women in antenatal clinics were not always aware that they had the right to decline an HIV test. CONCLUSION: Policy and practice on HIV testing and counselling in Africa has shifted from a cautious approach that emphasizes confidentiality to greater acceptance of the routine offer of HIV testing. The introduction of PITC in clinical settings has contributed to increased HIV testing in several of these settings. Most patients regard PITC as acceptable. However, other approaches are needed to reach people who do not consult health-care services
Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species
Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, LeuâGluâLeuâGlu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether LeuâGluâLeuâGlu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species. Š 2015, MDPI AG. All rights Reserved.published_or_final_versio
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