8 research outputs found

    Proposal for a methodology based on XRD and SEM-EDS to monitor effects of lime-treatment on clayey soils

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    The aim of this paper is to present the results of X-ray diffraction (XRD) tests and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analyses on a natural and lime-treated clay, in order to determine the percentage of lime able to stabilize soil. For this reason, XRD test analyses have been conducted on natural soil (TQ0) and on two different mixtures (TQ3 and TQ5): The former with 3% and the latter with 5% by mass of quicklime. These mixtures have been analyzed at different curing times: At the addition of lime (0 d), and after a mellowing period of 7 and 28 d. The obtained results show that 3% of CaO is the percentage of quicklime able to modify the material (initial consumption of lime (ICL) and 5% of CaO is the percentage able to stabilize it (lime stabilization optimum (LSO). Finally, SEM images allowed for the monitoring of the process of reactions between the soil and lime during the mellowing period, while EDS analyses validated the XRD results in terms of chemical composition of the examined soil. For the examined natural clay, statistical analysis of the obtained EDS results identified a linear regression curve between the added quicklime and the after-treatment Ca content. The proposed approach could be adopted to calculate the content of calcium after the treatment and verify the in situ-added CaO during roadworks or at the end of them

    Worldwide Effects of Coronavirus Disease Pandemic on Tuberculosis Services, January–April 2020

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    Coronavirus disease has disrupted tuberculosis services globally. Data from 33 centers in 16 countries on 5 continents showed that attendance at tuberculosis centers was lower during the first 4 months of the pandemic in 2020 than for the same period in 2019. Resources are needed to ensure tuberculosis care continuity during the pandemic

    Congenital Corneal Anesthesia and Neurotrophic Keratitis: Diagnosis and Management

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    Neurotrophic keratitis (NK) is a rare degenerative disease of the cornea caused by an impairment of corneal sensory innervation, characterized by decreased or absent corneal sensitivity resulting in epithelial keratopathy, ulceration, and perforation. The aetiopathogenesis of corneal sensory innervation impairment in children recognizes the same range of causes as adults, although they are much less frequent in the pediatric population. Some extremely rare congenital diseases could be considered in the aetiopathogenesis of NK in children. Congenital corneal anesthesia is an extremely rare condition that carries considerable diagnostic and therapeutic problems. Typically the onset is up to 3 years of age and the cornea may be affected in isolation or the sensory deficit may exist as a component of a congenital syndrome, or it may be associated with systemic somatic anomalies. Accurate diagnosis and recognition of risk factors is important for lessening long-term sequelae of this condition. Treatment should include frequent topical lubrication and bandage corneal or scleral contact lenses. Surgery may be needed in refractory cases. The purpose of this review is to summarize and update data available on congenital causes and treatment of corneal hypo/anesthesia and, in turn, on congenital NK

    Hybridizing CBFM and ray tracing for on-body propagation

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    An extension of the Characteristic Basis Function Method (CBFM) for handling radiating problems involving structures with apertures (slots) is hybridized with a ray tracing based solver to characterize the propagation between a transmitting waveguide antenna and a generic receiver operating at 94 GHz, located in proximity of a human body. Specifically, CBFM is used to estimate the radiation pattern of the transmitter, which provides the radiation pattern model to be employed in the ray tracing solver. © 2013 IEEE

    Prognostic value of interferon-γ release assays and tuberculin skin test in predicting the development of active tuberculosis (UK PREDICT TB): a prospective cohort study.

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    BACKGROUND: Tackling tuberculosis requires testing and treatment of latent tuberculosis in high-risk groups. The aim of this study was to estimate the predictive values of the tuberculin skin test (TST) and two interferon-γ release assays (IGRAs) for the development of active tuberculosis in high-risk groups-ie, people in recent contact with active tuberculosis cases and from high-burden countries. METHOD: In this prospective cohort study, we recruited participants from 54 centres (eg, clinics, community settings) in London, Birmingham, and Leicester in the UK. Participants were eligible if they were aged 16 years or older and at high risk for latent tuberculosis infection (ie, recent contact with someone with active tuberculosis [contacts] or a migrant who had arrived in the UK in the past 5 years from-or who frequently travelled to-a country with a high burden of tuberculosis [migrants]). Exclusion criteria included prevalent cases of tuberculosis, and participants who were treated for latent tuberculosis after a positive test result in this study. Each participant received three tests (QuantiFERON-TB Gold-In Tube, T-SPOT.TB, and a Mantoux TST). A positive TST result was reported using three thresholds: 5 mm (TST-5), 10 mm (TST-10), and greater than 5 mm in BCG-naive or 15 mm in BCG-vaccinated (TST-15) participants. Participants were followed up from recruitment to development of tuberculosis or censoring. Incident tuberculosis cases were identified by national tuberculosis databases, telephone interview, and review of medical notes. Our primary objective was to estimate the prognostic value of IGRAs compared with TST, assessed by the ratio of incidence rate ratios and predictive values for tuberculosis development. The study was registered with ClinicalTrials.gov, NCT01162265, and is now complete. FINDINGS: Between May 4, 2010, and June 1, 2015, 10 045 people were recruited, of whom 9610 were eligible for inclusion. Of this cohort, 4861 (50·6%) were contacts and 4749 (49·4%) were migrants. Participants were followed up for a median of 2·9 years (range 21 days to 5·9 years). 97 (1·0%) of 9610 participants developed active tuberculosis (77 [1·2%] of 6380 with results for all three tests). In all tests, annual incidence of tuberculosis was very low in those who tested negatively (ranging from 1·2 per 1000 person-years, 95% CI 0·6-2·0 for TST-5 to 1·9 per 1000 person-years, 95% CI 1·3-2·7, for QuantiFERON-TB Gold In-Tube). Annual incidence in participants who tested positively were highest for T-SPOT.TB (13·2 per 1000 person-years, 95% CI 9·9-17·4), TST-15 (11·1 per 1000 person-years, 8·3-14·6), and QuantiFERON-TB Gold In-Tube (10·1 per 1000 person-years, 7·4-13·4). Positive results for these tests were significantly better predictors of progression than TST-10 and TST-5 (eg, ratio of test positivity rates in those progressing to tuberculosis compared with those not progressing T-SPOT.TB vs TST-5: 1·99, 95% CI 1·68-2·34; p<0·0001). However, TST-5 identified a higher proportion of participants who progressed to active tuberculosis (64 [83%] of 77 tested) than all other tests and TST thresholds (≤75%). INTERPRETATION: IGRA-based or BCG-stratified TST strategies appear most suited to screening for potential disease progression among high-risk groups. Further work will be needed to assess country-specific cost-effectiveness of each screening test, and in the absence of highly specific diagnostic tests, cheap non-toxic treatments need to be developed that could be given to larger groups of people at potential risk. FUNDING: National Institute for Health Research Health Technology Assessment Programme 08-68-01

    Polythiophenes inhibit prion propagation by stabilizing PrP aggregates

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    LCPs interact with ordered protein aggregates and sensitively detect amyloids of many different proteins, suggesting that they may possess antiprion properties. Here we show that a variety of anionic, cationic and zwitterionic LCPs reduced the infectivity of prion-containing brain homogenates and of prion-infected cerebellar organotypic cultured slices COCS, and decreased the amount of PrP(Sc) oligomers that could be captured in an avidity assay. Paradoxically, treatment enhanced the resistance of PrP(Sc) to proteolysis, and triggered the compaction and enhanced the resistance to proteolysis of recombinant mPrP(23-231) fibers. These results suggest that LCPs act as antiprion agents by transitioning PrP aggregates into structures with reduced frangibility. Moreover, ELISA on COCS and in vitro conversion assays with mPrP(23-231) indicated that PTAA may additionally interfere with the generation of PrP(Sc) by stabilizing the conformation of PrP(C) or of a transition intermediate. Therefore, LCPs represent a novel class of antiprion agents whose mode of action appears to rely on hyperstabilization, rather than destabilization, of PrP(Sc) deposits
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