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Alkene epoxidation using the Mukaiyama process involving O2 and a sacrificial aldehyde, as the first step of the global alkene oxidative carboxylation, does not necessarily require a metal catalyst.

Ocular lesions in burns are common and diagnosis is often late, leading to functional impairment including loss of vision to these individuals. A retrospective study was conducted to assess ocular lesions in burns during ICU stay (01/01/2013 to 30/09/2020) in a 20-bed burn ICU in Tunis. Twenty-six cases combining burns and ocular lesions were reviewed. The average age was 26, with a sex-ratio 3.3/1. TBSA was 22±13%. Face was affected in 23 patients, and mechanical ventilation was required in 10 cases. Diagnosis of ocular lesion was noted at 4.5 H (1-33 H) after burn injury. Main clinical signs were: eye redness (n=5) and purulent eye discharge (n=5). Lesions were mainly corneal abscess and corneal ulcer. Treatment combined local antibiotics (n=16) associated to systemic antibiotics in 10 cases. Surgery was required in 2 cases. Loss of vision was noted in 2 patients. Risk factors of corneal abscess were: facial burn (p=0,01); burn depth (p=0,02) and mechanical ventilation (p=0,04).

This thesis concerns the experiment design and the identification of non-fractional multi-input-single-output systems (MISO) from a transfer function representation. Concerning the experiment design, a study has been carried out to adapt the excitation signal to the studied system in order to estimate its parameters, one or two parameters of a second kind transfer function, with the best possible accuracy. Concerning the identification of MISO systems, two methods have been mainly developed. One is based on the optimal instrumental variable, which initially allows to estimate only the coefficients, and which has been extended for the estimation of the derivation orders, by integrating the instrumental variable with a nonlinear programming technique. The other method is based on the minimization of the output error which offers the advantage of estimating the coefficients and the derivation orders simultaneously, namely the MISO-oosrivcf and the MISO-oe. A notion of S-commensurability (structured commensurability) has been introduced to limit the number of parameters to be estimated of a multi-input-single-output (MISO) system, thus improving the convergence of identification methods. When the derivation orders are unknown, three variants have been proposed: either a global S-commensurable order is estimated for the whole fractional multi-input-single-output (MISO) system, or local S-commensurable orders are estimated for each subsystem, or all derivation orders are estimated without the S-commensurability constraint. An initialization procedure is proposed, consisting in estimating first a global S-commensurable model, then the local S-commensurable orders, and finally all the derivation orders. Finally, an application to the identification of the Earth's climate system is proposed to predict future temperature evolutions at the end of the thesis., Cette thèse concerne la planification d'expérience et l'identification de systèmes non entiers multi-entrées-mono-sortie (MISO) à partir d'une représentation par fonctions de transfert. Concernant la planification d'expériences, une étude a été menée pour adapter le signal d'excitation au système étudié afin d'estimer ses paramètres avec la meilleure précision possible un ou deux paramètres d'une fonction de transfert de deuxième espèce. Concernant l'identification de systèmes MISO, deux méthodes ont été principalement développées. L'une basée sur la variable instrumentale optimale, qui permet initialement d'estimer uniquement les coefficients, et qui a été étendue pour l'estimation des ordres de dérivation, en intégrant la variable instrumentale avec une technique de programmation non linéaire. L'autre méthode est basée sur la minimisation de l'erreur de sortie qui offre l'avantage d'estimer les coefficients et les ordres de dérivation simultanément, à savoir la MISO-oosrivcf et la MISO-oe. Une notion de S-commensurabilité (commensurabilité structurée) a été introduite pour limiter le nombre de paramètres à estimer d'un système multi-entrées-mono-sortie, ce qui permet d'améliorer la convergence des méthodes d'identification. Lorsque les ordres de dérivation sont inconnus, trois variantes ont été proposées : soit un ordre S-commensurable global est estimé pour l'ensemble du système multi-entrées-mono-sortie non entier, soit des ordres S-commensurables locaux sont estimés pour chaque sous-système, soit encore tous les ordres de dérivation sont estimés sans la contrainte de S-commensurabilité. Une procédure d'initialisation est proposée, consistant à estimer d'abord un modèle S-commensurable global, puis les ordres S-commensurables locaux, et enfin tous les ordres de dérivation. Enfin une application à l'identification du système climatique terrestre est proposée pour prédire les évolutions futures de la température à la fin de la thèse.

Pulmonary capillary leak syndrome secondary to influenza SARS‐CoV‐2virus infection was not previously reported. We report 2 cases. The diagnosis of non‐cardiogenic pulmonary edema due to pulmonary capillary leak syndrome SARS‐CoV‐2 virus infection was obtained by a medical committee of 6 physicians. The diagnosis of COVID‐19 infection is confirmed by reverse transcription polymerase chain reaction (RT‐PCR) test. Moreover, in this specific endemic situation, and according to the British Society of Thoracic Imaging expert reference group update, we took account of chest CT‐Scan results in the early detection of COVID‐19 pneumonia. Our 2 patients with a confirmed influenza SARS‐CoV‐2virus infection had respiratory distress with lung crackles on auscultation of one or both lungs and with alveolar pulmonary edema on the chest CT‐Scan. The cardiogenic nature of pulmonary edema was ruled out in both cases by a transthoracic echocardiography showing normal systolic and diastolic functions. Our patients were treated by oxygen via face mask in one case and mechanical ventilation as supportive treatment in the other patient. Hydroxychloroquine (600mg/day), Azithromycine, steroids (dexamethasone 20mg/day), vitamin C (3g/day), Zinc, diuretics and Enoxaparine were equally used for the two patients. Evolution was marked by a good outcome in both of them. In summary, acute respiratory failure is a rare but major complication of COVID‐19 virus infection. It is due to pulmonary capillary leak syndrome. Treatment is based on a good oxygenation, intravenous corticosteroids, diuretics, Azithromycine, vitamin C, and other symptomatic treatments. This article is protected by copyright. All rights reserved.

This paper proposes an instrumental variable approach for continuous-time system identification using fractional models with multiple input single output context. This work is an extension of the simplified refined instrumental variable approach (srivcf ) developed for single input-single output fractional model identification (Malti et al. (2008a); Victor et al. (2013)) to the multiple input-single output case. Monte Carlo simulation analysis is used to demonstrate the performance of the proposed approach. A study is then provided to motivate differentiation order estimation, and more specifically, commensurate order estimation.

Supported ruthenium nanoparticles were prepared through the chemical reduction of aqueous Ru(III) species previously loaded (1 or 5 wt%) onto DD3 kaolin through an ion-exchanged pathway. Resulting nanoporous materials were characterized by XRF, XRD, TEM, EDX, and N2 sorption measurements, and then used as catalysts in the liquid phase aerobic oxidation of benzyl alcohol. Benzaldehyde was obtained as the main product with a 97% yield at 100% alcohol conversion at 100 °C in the presence of Ru-DD3 (5%) using 10 mL/min O2 flow and 10 mol% of tert-butyl hydroperoxide with respect to the substrate. Oxidation tests were more efficient in the case of Ru-DD3 (5%) than with other Ru-based solids such as Ru-HZSM-5 (5%). It was also shown that, in the presence of Ru-DD3 (5%), the aerobic oxidation of benylalcohol in the presence of an amine (aniline) gives rise to the imine instead of the aldehyde through a one-pot oxidation and condensation process.

Zusammenfassung Sexueller Missbrauch in Institutionen stellt ein besonders schwerwiegendes Versagen des staatlichen Kinderschutzes dar. Die Folgen für die Betroffenen sind häufig sehr erheblich und bleiben lebenslänglich. Daher ist die Entwicklung von umfassenden Präventions- und Interventionsmaßnahmen und von Aufarbeitungsbemühungen so wie sie in Schutzkonzepten gegen sexualisierte Gewalt in Institutionen konzeptionell angelegt sind, sehr bedeutsam.

In this dissertation, we are concerned with the role of the local energy inequalities in the theory of the partial regularity of the weak solutions of the Navier-Stokes equations in the direction of the Theorem of Caffarelli, Kohn and Nirenberg.We distinguish three parts. The first part of the thesis deals essentially with the announcement by the Korean mathematician Choe at Waseda in 2013 of the demonstration of a new local energy inequality which applies to any weak solution of the Navier-Stokes equations without any hypothesis on the pressure, and which allowed to extend the results of partial regularity of Caffarelli, Kohn and Nirenberg to all weak solutions and not only to the suitable one.A rigorous study of the proof of Choe's inequality allowed us to conclude that this proof was false a priori for the case of a general solution, and Choe's main theorem (which was supposed to give us a regularity in time and space variables outside of an extremely small set of singularity) was contradicted by a counter-example of Serrin that linked the regularity in time to the assumptions on the pressure.In this first part, we have drafted a conscientious proof of the inequality introduced by Choe by adding an extra hypotheses that had to be introduced in order to demonstrate it. However, the new energy inequality (which did not involve the pressure) did not serve to extend Choe's assertions, but we were able to identify a new variable inspired by Choe's proof that allowed us to introduce our main result.The second part of the thesis is devoted to deeply studying the new variable suggested by a part of Choe's work. Indeed, we could assimilate a new variable $\vv$ linked to the curl of the solution $\vu$, and by studying $\vv $, using a mixture of the Serrin theory and that of Caffarelli, Kohn and Nirenberg we obtained a partial regularity result which does not apply to any weak solution (contrary to Choe's statement) but to a wider class than the suitable solutions (in the sense of Caffarelli, Kohn and Nirenberg): the notion of dissipative solutions was introduced following the work of Duchon and Robert done in 2000 and this allows us to positively include the counter example of Serrin in our new theory.The third and last part is intended for the study of the stability of dissipative solutions by weak-*convergence. Indeed, we consider a bounded sequence $\vu_{n}$ in $L^{\infty}_t L^2_x\cap L^{2}_t H^1_x$, a bounded force $\vf_{n}$ in $L^{\frac{10}{7}}_t L^{\frac{10}{7}}_x$ and a pressure $p_{n}\in \mathcal{D}'(Q)$. We also suppose that $\vu_{n}$ is dissipative in the sense of the definition given in the second part and we will prove that the limit $\vu$ of a subsequence $\vu_ {n_ {k}}$ is a solution of the Navier-Stokes equations and is dissipative., Cette thèse est consacrée au rôle des inégalités d'énergie locales dans la théorie de la régularité partielle des solutions faibles des équations de Navier-Stokes dans le sens du Théorème de Caffarelli, Kohn et Nirenberg.Nous distinguons trois parties. La première partie de la thèse traite essentiellement l'annonce faite par le mathématicien coréen Choe à Waseda en $2013$ d'une nouvelle inégalité d'énergie locale qui s'applique à toute solution faible des équations de Navier-Stokes, sans aucune hypothèse sur la pression, et qui permettait d'étendre les résultats de régularité partielle de Caffarelli, Kohn et Nirenberg à toutes les solutions faibles et pas seulement aux solutions adaptées.Une étude de la preuve de l'inégalité de Choe nous permettait de conclure que cette preuve était fausse a priori pour le cas d'une solution générale, et le théorème principal de Choe (qui était sensé nous donner une régularité en temps et en espace en dehors d'un ensemble de singularité extrêmement petit) était contredit par un contre exemple de Serrin qui liait la régularité en temps à des hypothèses sur la pression.Dans cette première partie on a rédigé une preuve rigoureuse de l'inégalité introduite par Choe en rajoutant des hypothèses supplémentaires qu'il fallait introduire pour la démontrer. Néanmoins, cette nouvelle inégalité d'énergie (qui ne fait pas intervenir la pression) nous ne sert pas à prolonger les affirmations de Choe, mais on a pu identifier une nouvelle variable, inspirée de la preuve de Choe, qui nous a permit d'introduire notre résultat principal.En effet, la deuxième partie de la thèse est consacrée à étudier profondément la nouvelle variable suggérée par une partie du travail de Choe. On a pu assimiler une nouvelle variable $\vv$ liée au rotationel de la solution $\vu$ et en étudiant $\vv$, à l'aide d'un mélange de la théorie de Serrin et celle de Caffarelli, Kohn et Nirenberg on a obtenu un résultat de régularité partielle qui ne s'applique pas à toute solution faible (contrairement à l'énoncé de Choe) mais à une classe plus large que les solutions adaptées (au sens de Caffarelli, Kohn et Nirenberg): la notion de solution dissipative a été introduite en suivant les travaux de Duchon et Robert fait en 2000 et cette notion nous permet d'inclure positivement le contre exemple de Serrin dans notre nouvelle théorie.La troisième et dernière partie de cette thèse est destinée à l'étude de la stabilité des solutions dissipatives par convergence *-faible. En effet, on considère une suite $\vu_{n}$ qui converge faiblement dans $L^{\infty}_t L^2_x\cap L^{2}_t H^1_x$, une force extérieure $\vf_{n}$ qui converge faiblement dans $L^{\frac{10}{7}}_t L^{\frac{10}{7}}_x$ à divergence nulle et une pression $p_{n}\in \mathcal{D}'(Q)$. On suppose aussi que $\vu_{n}$ est dissipative au sens de la définition donnée dans la deuxième partie et on va prouver que la limite $\vu$ d'une sous suite $\vu_{n_{k}}$ est une solution des équations de Navier-Stokes et elle est dissipative.

We present experimental measurements of resistivity and thermoelectric power of liquid alloys, Al 1−x –Mn x , (x = 0.12, 0.14, 0.16, 0.18, 0.20). The resistivity increases from 28.88 μΩ cm for pure aluminum to 123.3 μΩ cm for the alloy. No resistivity extremum is observed near the Mn concentration x = 0.14, in contrast to that observed in the quasi-crystalline state. At 1323 K. The temperature coefficient of the experimental resistivity is found to have a minimum value in the near vicinity of x = 0.16. For all these five compositions the thermoelectric power is negative and does not display any anomaly. Also we have proposed theoretical model, based on Faber Ziman formalism, to calculate both resistivity and the thermoelectric power. The neutron scattering experiment on Al 0.80 Mn 0.20 liquid alloy confirmed that the effective spin of Manganese atoms had a mean value around 1 and that the Manganese could exist in two states of different magnetic moments. By minimizing the energy of the spin flip, we demonstrated the fact that Manganese appears in Al 1−x Mn x alloys as a mixture of Manganese atoms of spin 1/2 and 3/2 in proportions equal to 7/12 and 5/12, respectively. The Manganese atoms with one spin value different of zero may be considered as a binary alloy (B. Grosdidier, A. Ben Abdellah, K. Bouziane, S. M. Mujibur Rahman and J. G. Gasser, Phil. Mag. 93 no 26 (2013) p.3576.) owing to the spin dependence of the exchange and correlation. In this work, we treated Manganese with its two spin values as a quaternary alloy. Consequently, in our calculations, we treated Al–Mn as five component alloys. This allowing us to extend the Faber Ziman formalism originally designed for a binary alloy to a five-component formalism. Our theoretical results are in fairly good agreement with our experimental values which validates the assumptions of our model.

International audience; We have investigated the electrical properties of the BiMn alloy by measuring experimentally The resistivity and thermoelectric power(TEP) of liquid alloys xx1MnBi− (x=0.10, 0.20, 0.30, 0.40, 0.45). We have observed that The resistivity increases from cm⋅Ωμ52.169at 1050°C for pure Bismuth to cm⋅Ωμ67.221for the alloy; while the thermoelectric power is negative and does not present any anomalies. In this work, we have been able to demonstrate that Manganese appears under a mixture of atoms of spin 1/2 and 3/2 states in the liquid alloy. During our resistivity calculation, xx1MnBi−was treated as a 5-components alloy, this allowed us to use an extended Faber-Ziman formalism. Mentioning that our theoretical model was based on two types of muffin tin potentials in the t-matrix, that is spin up and spin down. The resistivity is treated as the result the interferences between the two spin states of each electron with coherent and incoherent contributions. The calculated values are compared to our experimental values and give good results for xx1MnBi−alloy.

This paper deals with the problem of experiment design in system identification using elementary fractional models of the second type. It is based on a frequency domain approach and answers the question what is the best sine input signal maximizing D-optimality criterion of the Fisher Information Matrix. A single parameter is assumed to be unknown: gain, pseudo-damping factor, natural frequency, or the commensurate differentiation order. Analogy with second order systems, with the differentiation order equal to one, is pointed out. This work extends the previous one (Abrashov et al., 2017) which dealt with elementary fractional systems of the first kind.

W–S–N-tri-doped TiO 2 photocatalysts (WSNTiO 2 ) were prepared by a simple sol–gel method. Tungstic acid, sodium sulfate and urea were used as tungsten, sulfur and nitrogen sources, respectively. The morphology and microstructure characteristics of the photocatalysts were evidenced by means of XRD, BET, TEM, SEM and UV–vis DRS techniques. The XRD results show that the main crystal phase of samples is anatase. It was also found that the tri-doping of TiO 2 increases its BET specific surface area from 95 to 121 m 2 ·g −1 . Besides, it was shown that tri-doping narrows the band gap of TiO 2 effectively, which has greatly improved the photocatalytic activity in the visible light region. The photocatalytic activity of tri-doped TiO 2 powders was compared to that of bi-doped ones through the degradation of Congo Red (CR) under visible irradiation. Thus, the prepared 0.5% W–N–S–TiO 2 heat treated at 450 °C showed the best photocatalytic activity compared to the prepared pure TiO 2 , Degussa P25, and co-doped samples (WNTiO 2 and WSTiO 2 ). In particular, a Congo Red degradation rate of approximately 99% was reached after only 35 min of visible light irradiation in the presence of 0.5% of WNSTiO 2 . Total organic carbon (TOC) removal of CR was up to 72% and confirmed its significant mineralization in the presence of 0.5% of WNSTiO 2 photocatalyst.

Anatase TiO 2 nanorod photocatalysts were prepared following a two-step procedure, consisting first in the alkaline hydrothermal treatment at 150 °C for 24 h of commercial Aeroxide TiO 2 P25, and a subsequent calcination at a temperature between 350 °C and 700 °C. The final calcination led to the transformation of dried TiO 2 (B) nanotubes into pure anatase TiO 2 nanorods, together with a decrease in surface area as well as with the maintain of both one-dimensional morphology and anatase phase with the temperature increase. In the case of the methanol degradation, an optimum in terms of performances was obtained for TiO 2 nanorods calcined at 500 °C, with a surface area of 122 m 2 /g. This resulted from balanced physicochemical properties with increasing the temperature, with the increase in TiO 2 crystallinity, beneficial for lowering the recombination rate, and the decrease in surface area, associated to the increase in the anatase crystallite size, that lower both adsorption capacity of TiO 2 nanorods and ability to produce OH radicals. By contrast, the optimum in terms of conversion or sulfur removal rate was observed for nanorods calcined at 380 °C in the more rarely studied photocatalytic oxidation of H 2 S, for which the accumulation at the surface of sulfates as ultimate reaction products deactivates the photocatalyst. Indeed, TiO 2 nanorods calcined at a lower temperature of 380 °C suffered from a strongly less marked deactivation than the Aeroxide TiO 2 P25 reference and nanorods calcined at lower as well as at higher temperatures. They might take advantage of a higher surface area of 219 m 2 /g for overcoming their detrimental lower crystallinity and thus improving their resistance to deactivation, by allowing the storage of larger amounts of poisoning sulfates.

A series of W-modified TiO2 (W–TiO2) photocatalysts were synthesized by a simple sol–gel method. The new photocatalysts were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis-diffuse reflectance spectroscopy (DRS), and Brunauer, Emmett and Teller (BET) surface area analyzer. The photoactivity of the W–TiO2 photocatalysts was evaluated by the photocatalytic oxidation of Congo red (CR) dye. It was found that the average size of the prepared photocatalysts is 10 nm. Moreover, they have high surface areas (∼ 216 m2 g−1) and their light-absorption extends to the visible region compared to pure TiO2. The effects of W-loading and of the calcination temperature of the prepared photocatalysts on their photocatalytic activity were also studied. The obtained results show that the W0.5–TiO2 photocatalyst calcined at 350 °C is much highly photoactive than non-doped or highly doped TiO2. The enhanced photocatalytic activity of the weakly doped TiO2 may be attributed to the increase in the charge separation efficiency and the presence of surface acidity on the W0.5–TiO2 photocatalyst.

Hybrid TiO2–hydroxypropyl methyl cellulose (TiO2–HPMC) nanophotocatalysts were prepared by a simple in situ synthesis. The weight ratios of HPMC-to-TiO2 were 5, 10 and 20%, respectively. The as-prepared nanocomposites were characterized by XRD, XPS, UV–vis DRS, ATG and BET surface area analysis. Surface morphology was assessed by the means of SEM. The photocatalytic degradation of 4-nitrophenol (4-NP) in neutral aqueous solution under visible light irradiation was examined to evaluate the efficiency of the hybrids in comparison to pure TiO2. The results indicated that the in situ hybridization of TiO2 with HPMC significantly increases its specific surface area and extends its light absorption range to the visible region. Consequently, TiO2–HPMC nanocomposites were photocatalytically much more active than pure TiO2. Moreover, the TiO2–HPMC hybrids were found to be sufficiently photostable after five experimental runs.

International audience