7 research outputs found
Nonlinear Analysis of Cable Structures with Geometric Constraints
International audienceThe purpose of this paper is the modelling in large displacement of systems composed of a rigid platform suspended by flexible cables, as can be observed in lifting systems of a construction crane or in cable-driven parallel robots (CDPRs). A recent approach has been proposed in the literature to model the nonlinear behavior of a cable element based on three dimensional catenary elastic modelling and the general displacement control method (GDCM) as solver. In this paper, two modifications of this method are proposed to take into account the geometric constraints coupling the large displacements of the cable extremities. The first approach is to consider these constraints using penalty functions thus modifying the tangent stiffness matrix and the second method by adding external explicit elastic forces. These two methods are tested and compared by using numerical examples. The first method is numerically safer because it is not dependent on the poor numerical conditioning of the cable’stiffness matrix encountered when internal cable’s tension cannot balance the external forces
[78] Idiopathic hypercalciuria complicated by polyuropolydipsic syndrome during pregnancy
Objective: To report on a case of idiopathic hypercalciuria complicated by polyuropolydipsic syndrome during pregnancy. Idiopathic hypercalciuria is most often manifested by urinary lithiasis and/or nephrocalcinosis. The polyuropolydipsic syndrome is a rare complication of this condition and exposes the patient to the risk of hydroelectrolytic disorders. Thiazide diuretics are indicated during this syndrome in the absence of a contraindication. Methods: We report the case of pregnancy during idiopathic hypercalciuria complicated by polyuropolydipsic syndrome. Results: A 33-year-old woman, with no personal or familial pathological history, was referred for polyuropolydipsic syndrome. She had no extra-renal manifestations and her clinical examination was normal. Her diuresis was 6 L/24 h and the biological assessment showed a hypercalciuria at 17.5 mmol/24 h persisting after adjusting the intakes of salts and proteins. Calcium, phosphataemia, 25-OH vitamin D, and parathyroid hormone were normal. The patient was put on thiazide diuretic and the evolution was marked by the normalisation of diuresis and a decrease in calciuria. Before conception the treatment was stopped, and the patient had a pregnancy without complications Conclusion: Pregnancy during idiopathic hypercalciuria with polydipsic polyuria syndrome was completed without complications in this case. The literature is poor regarding this affliction in the pregnant woman
Eccentricity Faults Diagnosis in Permanent Magnet Synchronous Motors: a Finite Element-Based Approach
International audienc
Incidence and challenges in management of hemodialysis catheter-related infections
Abstract Catheter-related infections (CRI) are a major cause of morbidity and mortality in chronic hemodialysis (HD) patients. In this paper, we share our experience with CRI in HD patients. We recorded 49 cases of CRI among 167 patients during a period of 40 months (January 2018–April 2021). The incidence of CRI was 3.7 per 1000 catheter-days. The revealing symptoms were dominated by fever or chills (90%). Inflammatory signs were observed in 74% of cases with respectively concurrent exit-site (51%) and tunnel infection (6%). The biological inflammatory syndrome was found in 74% of patients (average CRP level = 198.9 mg/l). Blood cultures were performed in all cases and were positive in 65% of cases. Thirteen patients have been diagnosed with Infection complications, which were respectively infective endocarditis in 7 cases, septic arthritis in 3 cases, infective myositis in one case, cerebral thrombophlebitis in 1 case and mediastinitis in 1 case. The death occurred in eleven patients, it was due to septic shock in 9 cases, pulmonary embolism in one case and neurologic alterations related to cerebral thrombophlebitis. The mean seniority in HD was 16.5 months in the group with CRI and 3.7 months in the group without CRI (p < 0.04). We did not notice significant difference in mortality between tunnelled and non-tunnelled catheters. CRI does not seem to be more severe in patients with diabetes. Duration of use of the HD catheter (p < 0.007) and ferritin level (p < 0.0001) were independent factors that predispose to CRI in our population
Analysis of the Cultivable Endophytic Bacterial Diversity in the Date Palm (Phoenix dactylifera L.) and Evaluation of Its Antagonistic Potential against Pathogenic Fusarium Species that Cause Date Palm Bayound Disease
International audienceBiological control still remains an unexploited issue in southern countries such as Tunisia. Thus, the present study focused on the diversity of cultivable endophytic bacteria in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera L.). In order to assess their antagonistic potential towards date palm pathogens, particularly Fusarium. Indeed, the Genus Fusarium includes the causative agent of the Bayound disease, Fusarium oxysporum, a major treat for date production North Africa. Twenty two bacterial isolates presenting distinct colony morphology on TSA media were selected. The latter were characterized using Gram staining, biochemical tests, and molecular identification techniques based on 16S rRNA gene sequencing. Cultivable endophytic isolates were assigned into seven distinct groups. The species Arthrobacter agilis and Bacillus subtilis exhibited lasting antagonistic properties against a range of Fusarium species including the causing agent of the Bayoud disease, thus demonstrating their strong potential for future applications in the inoculation of date palm trees for biocontrol purposes. The isolates showed extracellular enzymatic activity including cellulase (76, 92%), protease (69, 23%) and amylase (38, 46%). This study thus demonstrates for the first time that the diversity of endophytic bacteria is abundant in date palm trees (Phoenix dactylifera L.) and could present varying biotechnological applications and particularly disease control