108 research outputs found

    Shock models governed by an inverse gamma mixed Poisson process

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    We study three classes of shock models governed by an inverse gamma mixed Poisson process (IGMP), namely a mixed Poisson process with an inverse gamma mixing distribution. In particular, we analyze (1) the extreme shock model, (2) the delta-shock model, and the (3) cumulative shock model. For the latter, we assume a constant and an exponentially distributed random threshold and consider different choices for the distribution of the amount of damage caused by a single shock. For all the treated cases, we obtain the survival function, together with the expected value and the variance of the failure time. Some properties of the inverse gamma mixed Poisson process are also disclosed

    ON-LINE CONSISTENCY TESTS FOR BAR DETECTORS

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    In order to detect gravitational wave signals with resonant bar detectors using Wiener–Kolmogorov (WK) filters, both a model for the power spectrum density (PSD) of the noise and a signal template should be provided. As the analysis is not meant to handle non-gaussian data, we have to discriminate (and constrain to) time periods where the noise follows a quasi-stationary gaussian model. Within these periods, candidate events are selected in the WK filter output, and their fundamental parameters (time of arrival and amplitude) are computed. A necessary and sufficient condition for the reliability of such estimates is the consistency of the signal shape with the template. This is done performing a goodness-of-the-fit test

    Testing of optimal filters for gravitational wave signals: An experimental implementation

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    We have implemented likelihood testing of the performance of an optimal filter within the online analysis of AURIGA, a sub-Kelvin resonant-bar gravitational wave detector. We demonstrate the effectiveness of this technique in discriminating between impulsive mechanical excitations of the resonant-bar and other spurious excitations. This technique also ensures the accuracy of the estimated parameters such as the signal-to-noise ratio. The efficiency of the technique to deal with non-stationary noise and its application to data from a network of detectors are also discussed

    Initial operation of the International Gravitational Event Collaboration

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    The International Gravitational Event Collaboration, IGEC, is a coordinated effort by research groups operating gravitational wave detectors working towards the detection of millisecond bursts of gravitational waves. Here we report on the current IGEC resonant bar observatory, its data analysis procedures, the main properties of the first exchanged data set. Even though the available data set is not complete, in the years 1997 and 1998 up to four detectors were operating simultaneously. Preliminary results are mentioned.Comment: 8 pages, 2 figures, 3 tables; Proceeding of the GWDAW'99. Submitted to the International Journal of Modern Physic

    Base-editing-mediated dissection of a Îł-globin cis-regulatory element for the therapeutic reactivation of fetal hemoglobin expression

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    : Sickle cell disease and β-thalassemia affect the production of the adult β-hemoglobin chain. The clinical severity is lessened by mutations that cause fetal γ-globin expression in adult life (i.e., the hereditary persistence of fetal hemoglobin). Mutations clustering ~200 nucleotides upstream of the HBG transcriptional start sites either reduce binding of the LRF repressor or recruit the KLF1 activator. Here, we use base editing to generate a variety of mutations in the -200 region of the HBG promoters, including potent combinations of four to eight γ-globin-inducing mutations. Editing of patient hematopoietic stem/progenitor cells is safe, leads to fetal hemoglobin reactivation and rescues the pathological phenotype. Creation of a KLF1 activator binding site is the most potent strategy - even in long-term repopulating hematopoietic stem/progenitor cells. Compared with a Cas9-nuclease approach, base editing avoids the generation of insertions, deletions and large genomic rearrangements and results in higher γ-globin levels. Our results demonstrate that base editing of HBG promoters is a safe, universal strategy for treating β-hemoglobinopathies

    Status report of the gravitational wave detector AURIGA

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    We present the status of the ultracryogenic gravitational wave detector AURIGA, which is taking data since may 1997 with an energy sensitivity in the mK range and bandwidth greater than 1 Hz. The typical detector output is summarized in daily reports which are important tools for detector diagnostic and for checking the vetoes of periods of unsatisfactory operation of the detector

    Younger age at onset and sex predict celiac disease in children and adolescents with type 1 diabetes: an Italian multicenter study

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    OBJECTIVE— To estimate the prevalence of biopsy-confirmed celiac disease in Italian children and adolescents with type 1 diabetes and to assess whether age at onset of type 1 diabetes is independently associated with diagnosis of celiac disease. RESEARCH DESIGNANDMETHODS— The study group was a clinic-based cohort of children and adolescents with type 1 diabetes cared for in 25 Italian centers for childhood diabetes. Yearly screening for celiac disease was performed using IgA/IgG anti-gliadin and IgA anti-endomysium antibodies. RESULTS— Of the 4,322 children and adolescents (age 11.8 4.2 years) identified with type 1 diabetes, biopsy-confirmed celiac disease was diagnosed in 292 (prevalence 6.8%, 95% confidence interval [CI] 6.0 –7.6), with a higher risk seen in girls than in boys (odds ratio [OR] 1.93, 1.51–2.47). In 89% of these, diabetes was diagnosed before celiac disease. In logistic regression analyses, being younger at onset of diabetes, being female, and having a diagnosis of a thyroid disorder were independently associated with the risk of having diabetes and celiac disease. In comparison with subjects who were older than 9 years at onset of diabetes, subjects who were younger than 4 years at onset had an OR of 3.27 (2.20–4.85). CONCLUSIONS— We have provided evidence that 1) the prevalence of biopsy-confirmed celiac disease in children and adolescents with type 1 diabetes is high (6.8%); 2) the risk of having both diseases is threefold higher in children diagnosed with type 1 diabetes at age 4 years than in those age 9 years; and 3) girls have a higher risk of having both diseases than boys

    Understanding eating choices among university students: A study using data from cafeteria cashiers’ transactions

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    Objective: To illustrate the use of automatically collected data from cashier transactions to understand eating habits among university students using cafeteria and to identify individual characteristics associated with the diverse behaviors. Methods: The study was carried out at a large university located in Pisa, central Italy, using data about meals automatically recorded from cashier transaction meals during the academic year 2015−16 as well as data from the administrative archive of the university. A model-based clustering relying on multivariate beta distribution was used to cluster eating choices while multivariate multinomial logistic regressions were applied to identify variables associated to diverse clusters identified. Results: Considering 4643 students and about 200,000 meals consumed, results suggest that healthy eaters represented a minority (11.2 %) of the study population while the large part of students composed their meals combining grains with processed food or proteins (32.7 %) and limiting the choice of fruit (42.9 %). Male gender and younger age were associated with eating behavior not in line with recommendations for a healthy diet. Conclusions: Eating choice resulted to be “compromised” in most of students and specific characteristics associated with unhealthy choice were also identified that can help inform and target specific policy. The use of routinely collected data gives the opportunity to both cafeterias and university to take an active role in policy development

    The pharmacokinetics of ilaprazole for gastro-esophageal reflux treatment

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    Introduction: Approximately 20% of the Western population is affected by gastro-esophageal reflux disease (GERD). To date, proton pump inhibitors (PPIs) represent the mainstay of GERD medical treatment. However, despite their undoubted benefit, about 40% of GERD patients display an inadequate response to these drugs. Recently, a new PPI, ilaprazole , at oral doses of 10 mg has shown higher suppression of gastric acid secretion, more prolonged plasma half-life, and similar safety compared to 20 mg omeprazole. Areas covered: This review provides an update on the following points: pharmacokinetic profile and metabolism of ilaprazole in relation to its pharmacodynamic properties; comparative data on the pharmacokinetics and pharmacodynamics of ilaprazole with currently available PPIs; and implications for studies on the therapeutic efficacy of ilaprazole in GERD. Expert opinion: Different studies show that ilaprazole, a benzimidazole derivative, has an extended plasma half-life in comparison with all other approved PPIs. In addition, ilaprazole metabolism is not significantly influenced by CYP2C19, compared to the available PPIs. Furthermore, the pharmacological characteristics of ilaprazole confer theoretical advantages that are expected to translate into an improved acid control, particularly at night time. However, studies comparing the clinical pharmacokinetics and pharmacodynamics of ilaprazole with those of second-generation PPIs are insufficient. Moreover, further investigations assessing the efficacy of ilaprazole in the management of GERD are required. In healthy volunteers, as well as in patients with gastric or duodenal ulcers, ilaprazole has not shown clinically relevant changes in hematology and biochemistry testing, nor significant treatment-related adverse symptoms
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