20 research outputs found

    Statistical method for the determination of the ignition energy of dust cloud-experimental validation

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    International audiencePowdery materials such as metallic or polymer powders play a considerable role in many industrial processes. Their use requires the introduction of preventive safeguard to control the plants safety. The mitigation of an explosion hazard, according to the ATEX 137 Directive (1999/92/EU), requires, among other things, the assessment of the dust ignition sensitivity. PRISME laboratory (University of Orléans) has developed an experimental set-up and methodology, using the Langlie test, for the quick determination of the explosion sensitivity of dusts. This method requires only 20 shots and ignition sensitivity is evaluated through the E50 (energy with an ignition probability of 0.5). A Hartmann tube, with a volume of 1.3 l, was designed and built. Many results on the energy ignition thresholds of partially oxidised previous termaluminiumnext term were obtained using this experimental device (Baudry, 2007) and compared to literature. E50 evolution is the same as previous MIE but their respective values are different and previous MIE is lower than E50 however the link between E50 and previous MIE has not been elucidated. In this paper, the Langlie method is explained in detail for the determination of the parameters (mean value E50 and standard deviation σ) of the associated statistic law. The ignition probability versus applied energy is firstly measured for Lycopodium in order to validate the method. A comparison between the normal and the lognormal law was achieved and the best fit was obtained with the lognormal law. In a second part, the Langlie test was performed on different dusts such as previous aluminium, cornstarch, lycopodium, coal, and PA12 in order to determine E50 and σ for each dust. The energies E05 and E10 corresponding respectively to an ignition probability of 0.05 and 0.1 are determined with the lognormal law and compared to previous MIE find in literature. E05 and E10 values of ignition energy were found to be very close and were in good agreement with previous MIE in the literature

    Relationship between β-Thalassemia minor and Helicobacter pylori infection

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    Background: Until now, no study has been reported investigating the association between β-thalassemia minor and Helicobacter pylori (H. pylori) infection. This study was designed to compare H. pylori infection rate between β-thalassemia minor patients and healthy controls. Methods: A number of 100 β-thalassemia minor patients (50 males, 50 females) and 100 gender-matched healthy controls were prospectively recruited in this study in a period of 3 months. The study population consisted of the people who referred to a health center in Babol, North of Iran, for premarital counseling. H. pylori status was assessed by measuring the anti-H. pylori IgG antibodies using enzyme-linked immunosorbent assay. Demographic information and informed consent were collected from all participants. Results: The overall H. pylori infection rate was 43%. The infection was significantly more prevalent in thalassemia patients (53%) than in the controls (33%) in both univariate (OR=2.29, 95% CI: 1.3-4.06) and multivariable analyses (OR=2.05, 95% CI: 1.12-3.76). Age was the only significant factor which was positively correlated with the infection in β-thalassemia minor cases (OR=1.11, 95% CI: 1.02-1.2). Gender, blood groups, residency, and education level were not related to the infection. Conclusions: According to the results, it can be concluded that β-thalassemia minor patients are possibly more susceptible to H. pylori infection than healthy people. Further studies are needed to discover more about the exact mechanisms of increased susceptibility to H. pylori infection in β-thalassemia minor patients

    Unraveling the neurophysiology of muscle fatigue

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    Despite 100years of research since the seminal work of Angelo Mosso (1846-1910), our understanding of the interactions between the nervous system and muscle during the performance of fatiguing contractions remains rather rudimentary. Although the nervous system simply needs to provide an activation signal that will elicit the net muscle torque required for a prescribed action, changes in the number and diversity of synaptic inputs that must be integrated by the spinal motor neurons to accommodate the changes in the force-producing capabilities of the muscle fibers complicate the process of generating the requisite activation signal. This brief review examines two ways in which the activation signal can be compromised during sustained contractions and thereby contribute to the rate at which the muscles fatigue. These examples provide insight on the types of adjustments that occur in the nervous system during fatiguing contractions, but emphasize that much remains to be learned about the physiological processes that contribute to the phenomenon known as muscle fatigue.info:eu-repo/semantics/publishe

    Obesity in adult patients with inflammatory bowel disease: Clinical features and impact on disability. A cross-sectional survey from the GETAID

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    International audienceBackground: In recent years, an increasing prevalence of obesity in inflammatory bowel disease (IBD) has been observed. However, only a few studies have focused on the impact of overweight and obesity on IBD-related disability.Aims: To identify the factors associated with obese and overweight patients with IBD, including IBD-related disability.Patients and methods: In this cross-sectional study, we included 1704 consecutive patients with IBD in 42 centres affiliated with the Groupe d'Etude Therapeutique des Affections Inflammatoires du tube Digestif (GETAID) using a 4-page questionnaire. Factors associated with obesity and overweight were assessed using univariate and multivariate analyses (odds ratios (ORs) are provided with 95% confidence intervals).Results: The prevalence rates of overweight and obesity were 24.1% and 12.2%, respectively. Multivariable analyses were stratified by age, sex, type of IBD, clinical remission and age at diagnosis of IBD. Overweight was significantly associated with male sex (OR = 0.52, 95% CI [0.39-0.68], p < 0.001), age (OR = 1.02, 95% CI [1.01-1.03], p < 0.001) and body image subscore (OR = 1.15, 95% CI [1.10-1.20], p < 0.001) (Table 2). Obesity was significantly associated with age (OR = 1.03, 95% CI [1.02-1.04], p < 0.001), joint pain subscore (OR = 1.08, 95% CI [1.02-1.14], p < 0.001) and body image subscore (OR = 1.25, 95% CI [1.19-1.32], p < 0.001) (Table 3).Conclusion: The increasing prevalence of overweight and obesity in patients with IBD is associated with age and poorer body image. A holistic approach to IBD patient care should be encouraged to improve IBD-related disability and to prevent rheumatological and cardiovascular complications

    Effectiveness and Safety of Vedolizumab Induction Therapy for Patients with Inflammatory Bowel Disease

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    International audienceBackground & aims - Phase 3 trials have shown the efficacy of vedolizumab, which binds to integrin α4β7, in patients with Crohn's disease (CD) or ulcerative colitis (UC). We investigated the effectiveness and safety of vedolizumab in patients who failed anti-tumor necrosis factor therapy. Methods - From June through December 2014, there were 173 patients with CD and 121 patients with UC who were included in a multicenter nominative compassionate early access program granted by French regulatory agencies. This program provided patients with access to vedolizumab before it was authorized for marketing. Vedolizumab (300 mg) was administered intravenously at weeks 0, 2, and 6, and then every 8 weeks. Disease activity was assessed using the Harvey-Bradshaw Index for CD and the partial Mayo Clinic score for UC. We report results obtained after the 14-week induction phase. Results - Among the 294 patients treated with vedolizumab (mean age, 39.5 ± 14.0 y; mean disease duration, 10.8 ± 7.6 y; concomitant steroids, 44% of cases), 276 completed the induction period, however, 18 discontinued vedolizumab because of a lack of response (n = 14), infusion-related reaction (n = 2), or infections (n = 2). At week 14, 31% of patients with CD were in steroid-free clinical remission and 51% had a response; among patients with UC, 36% were in steroid-free clinical remission and 50% had a response. No deaths were reported. Severe adverse events occurred in 24 patients (8.2%), including 15 (5.1%) that led to vedolizumab discontinuation (1 case of pulmonary tuberculosis and 1 rectal adenocarcinoma). Conclusions - In a cohort of patients with CD or UC who failed previous anti-tumor necrosis factor therapy, approximately one third of patients achieved steroid-free clinical remission after 14 weeks of induction therapy with vedolizumab. This agent had an acceptable safety profile in these patients
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