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Background: SARS-CoV-2 is described to cause mild to moderate symptoms in children. To date, clinical data and symptoms of the Delta variant in pediatric patients are lacking. Aim: To describe clinical characteristics and outcomes of infants admitted in the pediatric intensive care unit (PICU) during the period of Delta variant predominance. Methods: We performed a retrospective study, between June 23, 2021 and August 16, 2021. We included children aged under 15 years, admitted to PICU with severe and critical form of SARS-CoV-2 infection as confirmed by RT-PCR. We reviewed medical records for all patients. Results: During the study period, 20 infants were included. The median age was 47 days (IQR: 26.5–77). The sex ratio was 0.8 (9 males). No underlying medical conditions were noted. Parents were not vaccinated. Respiratory involvement was the main feature to be observed in our cohort. Eleven patients had pediatric acute respiratory distress (PARDS) with a median oxygen saturation index (OSI) of 9 (IQR: 7–11). PARDS was mild in 4 cases, moderate in 5 cases and severe in 2 cases. Hemodynamic instability was observed in 4 cases. The main radiological finding was ground glass opacities in 11 cases. Seventeen patients were mechanically ventilated and 3 of them were escalated to high-frequency oscillatory ventilation. The median duration of mechanical ventilation was 6 days (IQR 2.5–12.5). The remaining patients were managed with high flow nasal cannula. Four patients died. Conclusion: We report herein a case series of very young infants, with no comorbidities, and with a life-threatening illness due to SARS-CoV-2 Delta variant.

Abstract We report herein a case series of infants, with no comorbidities, who developed a life‐threatening illness due to the SARS‐CoV‐2 Delta variant. We retrospectively reviewed the medical records of children, aged under 15 years, admitted to PICU, during the peak of Delta infection, between June 23 and August 16 2021, with severe and critical forms of SARS‐CoV‐2 infection, confirmed by RT‐PCR. Twenty infants were included, the median age was 47 days (IQR: 26.5–77) and sex ratio was 0.8. No underlying medical conditions were noted. Parents were not vaccinated. Respiratory involvement was the main feature observed. Eleven patients had paediatric acute respiratory distress (PARDS) with a median oxygen saturation index (OSI) of 9 (IQR: 7–11). PARDS was mild in four, moderate in five, and severe in two cases. Hemodynamic instability was observed in 4 cases. The main radiological finding was ground glass opacities in 11 cases. Seventeen patients were mechanically ventilated, and three of them were escalated to high‐frequency oscillatory ventilation. The median duration of mechanical ventilation was 6 days (IQR 2.5–12.5). The remaining patients were managed with high‐flow nasal cannula. Four patients died.

This paper focuses on the 2D visual servo-control of a mobile robot using a neural network (NN) with variable structure. The interaction matrix relating camera movement and changes in visual characteristics requires an estimation phase to determine its parameters as well as a camera calibration phase. It is common in applications related to mobile robotics that the robot model contains uncertainties generated by the sliding phenomenon. We suggest online identification, using NN to avoid this problem. The RBF NN is used to estimate the block formed by the interaction matrix and the reverse robot. Since the number of variables to be estimated is large, this can lead to the use of an excessive number of RBFs. We propose to use a single point of the scene which is sufficient to solve the problem. This problem reduction is possible thanks to flatness theory which allows to reduce the number of NN inputs from 8 inputs (4 image points) -generally used in the literature- to 2 (one image point) only. In order to further reduce the complexity of the proposed algorithm, the number of neurons for each layer and for each iteration is optimized. We use a neural network with variable structure to reach this objective. The very encouraging results obtained validate the proposed approach.

The increasing number of enlistees claiming their right to enroll in the programs of African Universities and the limited number of Higher Education Institutions (HEIs) were the prime reasons of students overcrowding in classes. Massive Open Online Courses (MOOCs) showed a potential to help limiting the challenges of massification in open access HEIs. As the literature review of the MOOC situation in Africa is still nascent, we will qualitatively share the experience of Cadi Ayyad University in Marrakech, Morocco (UCA) in launching a MOOC for its learners as a case study. Created in 2013, this MOOC was entitled UC@MOOC and appeared to respond to the challenges of massification in open access HEIs and the language difficulties faced by students. We will also present an overview of this project, its achievements and the quantity of knowledge delivery it accomplished. This MOOC experience attracted learners from other countries. And we have found that a shortage of MOOCs in Africa drove learners from other African francophone countries to learn from UC@MOOC. Yet a low-cost MOOC with certain limitations such as the weak ICT infrastructure available to the African public will thrive if operated using a MOOC platform and boosted its financial means.

Congenital hypogonadotropic hypogonadism (CHH) and its anosmia-associated form (Kallmann syndrome [KS]) are genetically heterogeneous. Among the >15 genes implicated in these conditions, mutations in FGF8 and FGFR1 account for ~12% of cases; notably, KAL1 and HS6ST1 are also involved in FGFR1 signaling and can be mutated in CHH. We therefore hypothesized that mutations in genes encoding a broader range of modulators of the FGFR1 pathway might contribute to the genetics of CHH as causal or modifier mutations. Thus, we aimed to (1) investigate whether CHH individuals harbor mutations in members of the so-called "FGF8 synexpression" group and (2) validate the ability of a bioinformatics algorithm on the basis of protein-protein interactome data (interactome-based affiliation scoring [IBAS]) to identify high-quality candidate genes. On the basis of sequence homology, expression, and structural and functional data, seven genes were selected and sequenced in 386 unrelated CHH individuals and 155 controls. Except for FGF18 and SPRY2, all other genes were found to be mutated in CHH individuals: FGF17 (n = 3 individuals), IL17RD (n = 8), DUSP6 (n = 5), SPRY4 (n = 14), and FLRT3 (n = 3). Independently, IBAS predicted FGF17 and IL17RD as the two top candidates in the entire proteome on the basis of a statistical test of their protein-protein interaction patterns to proteins known to be altered in CHH. Most of the FGF17 and IL17RD mutations altered protein function in vitro. IL17RD mutations were found only in KS individuals and were strongly linked to hearing loss (6/8 individuals). Mutations in genes encoding components of the FGF pathway are associated with complex modes of CHH inheritance and act primarily as contributors to an oligogenic genetic architecture underlying CHH.

Abstract Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic form of isolated gonadotropin‐releasing hormone (GnRH) deficiency caused by mutations in > 30 genes. Fibroblast growth factor receptor 1 (FGFR1) is the most frequently mutated gene in CHH and is implicated in GnRH neuron development and maintenance. We note that a CHH FGFR1 mutation (p.L342S) decreases signaling of the metabolic regulator FGF21 by impairing the association of FGFR1 with β‐Klotho (KLB), the obligate co‐receptor for FGF21. We thus hypothesized that the metabolic FGF21/KLB/FGFR1 pathway is involved in CHH. Genetic screening of 334 CHH patients identified seven heterozygous loss‐of‐function KLB mutations in 13 patients (4%). Most patients with KLB mutations (9/13) exhibited metabolic defects. In mice, lack of Klb led to delayed puberty, altered estrous cyclicity, and subfertility due to a hypothalamic defect associated with inability of GnRH neurons to release GnRH in response to FGF21. Peripheral FGF21 administration could indeed reach GnRH neurons through circumventricular organs in the hypothalamus. We conclude that FGF21/KLB/FGFR1 signaling plays an essential role in GnRH biology, potentially linking metabolism with reproduction.

This paper focuses mainly on investigating the mechanical properties of mortar reinforced with long-unidirectional vegetable fibers such as palm fibers and sisal fibers. The mechanical properties of fibers are also studied by considering fiber tensile test and fiber coupling test to analyze the twist-extension coupling and the tensile strength. Fibers were manually extracted from palm and sisal leaves. Laminated mortar specimens with fibers volume fraction ranging between 0% and 1.95% were prepared. The long unidirectional oriented fibers were placed on the lower part of the mortar. The influence of curing conditions on flexural strength of laminated mortar specimens was analyzed by considering two curing conditions: WCCC (wet chamber curing condition) and LCC (laboratory curing condition). Results confirm that the optimum fiber volume fraction was evaluated as 1.4% for Palm fiber-reinforced mortar. Better mechanical performance was accorded to the Palm fiber reinforced mortar in WCCC case due to the availability of water which is necessary to cement hydratation. Long Sisal fiber submitted to a tensile load shows coupling phenomenon between twist and extension which has a mechanical effect on the matrix behavior.

في إطار سياسة التنويع الاقتصادي في الجزائر، تتطور صناعة السيارات ، بعد تنفيذ مجموعة رينو في عام 2014، تليها عمليات وحدة التجميع الأخرى. منذ تأسيسها، ترغب شركات تصنيع السيارات في زيادة طاقتها الإنتاجية وتخطط لتصدير الفائض من إنتاجها، والذي يتماشى مع تطوير التعاقد من الباطن، من أجل تقليل فاتورة الواردات من المكونات وقطع الغيار في قطاع السيارات، والتي أصبحت مكلفة بشكل متزايد للسلطات العامة. Dans le cadre de la politique de diversification économique en Algérie, on assiste à un développement de l’industrie automobile, suite à l’implantation du Groupe Renault en 2014 suivi par d’autres implantations d’unités d’assemblage. Depuis leurs implantations, les constructeurs automobiles désirent augmenter leur capacité de production et envisagent d’exporter l’excédent de leur production, ce qui va avec le développement de la sous-traitance, afin de réduire la facture des importations des composants et pièces de rechange dans le secteur automobile, qui coûtent de plus en plus chers aux pouvoirs publics. In the policy of diversification of the Economy in Algeria, we assist of development of the automobile industry, after the implantation of Renault group in 2014 followed by other implantations of assembly units. Since their establishment, the car manufacturers wish to increase their production capacity and plan to export the surplus of their production, which goes with the development of the outsourcing, to reduce the invoice of the imports of the components and parts of spare parts in the automotive sector, which are becoming increasingly expensive for the public authorities.

SARS-CoV-2 is described to cause mild to moderate symptoms in children. To date, clinical data and symptoms of the Delta variant in pediatric patients are lacking. To describe clinical characteristics and outcomes of infants admitted in the pediatric intensive care unit (PICU) during the period of Delta variant predominance. We performed a retrospective study, between June 23, 2021 and August 16, 2021. We included children aged under 15 years, admitted to PICU with severe and critical form of SARS-CoV-2 infection as confirmed by RT-PCR. We reviewed medical records for all patients. During the study period, 20 infants were included. The median age was 47 days (IQR: 26.5–77). The sex ratio was 0.8 (9 males). No underlying medical conditions were noted. Parents were not vaccinated. Respiratory involvement was the main feature to be observed in our cohort. Eleven patients had pediatric acute respiratory distress (PARDS) with a median oxygen saturation index (OSI) of 9 (IQR: 7–11). PARDS was mild in 4 cases, moderate in 5 cases and severe in 2 cases. Hemodynamic instability was observed in 4 cases. The main radiological finding was ground glass opacities in 11 cases. Seventeen patients were mechanically ventilated and 3 of them were escalated to high-frequency oscillatory ventilation. The median duration of mechanical ventilation was 6 days (IQR 2.5–12.5). The remaining patients were managed with high flow nasal cannula. Four patients died. We report herein a case series of very young infants, with no comorbidities, and with a life-threatening illness due to SARS-CoV-2 Delta variant. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell, with low polluting emissions, is a great alternative to replace the traditional electrical power sources for automotive applications or for small stationary consumers. This paper presents a numerical method, for the fuel cell modelling, based on moving least squares (MLS). Experimental data have been used for developing an approximated model of the PEMFC function of the current density, air inlet pressure and operating temperature of the fuel cell. The method can be applied for modelling others fuel cell sub-systems, such as the compressor. The method can be used for off-line or on-line identification of the PEMFC stack.

The thermal effect of CO2 high-power laser cutting on cut surface of steel plates is investigated. The effect of the input laser cutting parameters on the melted zone depth (MZ), the heat affected zone depth (HAZ), and the microhardness beneath the cut surface is analyzed. A mathematical model is developed to relate the output process parameters to the input laser cutting parameters. Three input process parameters such as laser beam diameter, cutting speed, and laser power are investigated. Mathematical models for the melted zone and the heat affected zone depth are developed by using design of experiment approach (DOE). The results indicate that the input laser cutting parameters have major effect on melted zone, heat affected zone, and microhardness beneath cut surface. The MZ depth, the HAZ depth, and the microhardness beneath cut surface increase as laser power increases, but they decrease with increasing cutting speed. Laser beam diameter has a negligible effect on HAZ depth but it has a remarkable effect on MZ depth and HAZ microhardness. The melted zone depth and the heat affected zone depth can be reduced by increasing laser cutting speed and decreasing laser power and laser beam diameter.