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Abstract: Globally, the production of cold housing is seen as a major energy challenge of this new century. The economic development of developing countries, submitted their majority in hot climates, will lead to a growing demand chilling requirements. Yet currently, the production of cold solutions is mainly based on refrigeration systems major consumers of electrical energy.It is then necessary to prepare socio-economically acceptable solutions tailored to meet those needs without compromising future international commitments on the protection of the environment, particularly for reducing greenhouse gas emissions and better protection of the ozone layer by use of refrigerants neutral. For some years now, because of their impact on the environment, the use of halogenated refrigerants has been progressively subject to quotas. In this context, the use of “natural” refrigerants becomes a possible solution. We introduce in this work the merit of redeploying these natural refrigerants as an alternative solution to replace halogenated refrigerants. The solution to the environmental impacts of refrigerant gases would therefore pass by a gas which contains no chlorine no fluorine and does not reject any CO2 emissions in the atmosphere, in brief a green gas! The aim of our project is to contribute to the protection of our environment. Our motive being to produce cold for freezing foodstuffs and seeds, safeguarding pharmaceuticals and cooling of premises: temperature conditions, air qualities controlling and producing. This work is also concerned by a contribution to the reduction of greenhouse gases and by the replacement of the polluting cooling fluids (HCFC). It is essentially the refrigeration at low temperatures, lower than (-20°C), using the solar thermal energy, in order to improve the quality of life for many people especially in arid and semi arid regions in our country. [Copyright &y& Elsevier]

Abstract: From household refrigerator to cooling chambers and passing by air conditioners of all types, refrigerants are widely used in both industrial and domestic equipments. These fluids, which are henceforth being banned due in particular to their environmental toxicity, are expected to be replaced. Replacing them is a difficult task considering that the only solutions currently available are the so-called “natural” refrigerants, such as ammonia, hydrocarbons and CO2. The disadvantages of these products are mainly toxicity (NH3), flammability (HC) and high pressures (CO2). However, with minimal skills and compliance with safety rules, they do not eventually prove to be more dangerous than other fluids. Our endeavour in this project is intended as a contribution to the protection of our environment. The motive being to produce cold for freezing foodstuffs, preservation of pharmaceuticals and space cooling. We aim in particular at the control of clean (white) rooms. Considering the climate situation in our country, this cold production will be supported by the use of solar energy as a power source, in order to ensure the autonomy of these areas in arid and semi arid regions. An alternative that seems promised to a bright future. [Copyright &y& Elsevier]

COVID-19-associated mold infections have been increasingly reported, and the main entity is COVID-19-associated aspergillosis (CAPA). Similarly, COVID-19-associated mucormycosis has been reported in hematology, and its prevalence is high and has been increasing in the diabetic population in India during the third COVID-19 pandemic wave. Simultaneous infection with Mucorales and Aspergillus is rare and even rarer during COVID-19. Here, we report the case of a previously immunocompetent patient with severe SARS-CoV-2 infection complicated with probable CAPA and mucormycosis co-infection. Specific diagnostic tools for mucormycosis are lacking, and this case highlights the advantages of analyzing blood and respiratory samples using the quantitative polymerase chain reaction to detect these fungi. We further reviewed the literature on mixed Aspergillus /Mucorales invasive fungal diseases to provide an overview of patients presenting with both fungi and to identify characteristics of this rare infection. [ABSTRACT FROM AUTHOR]

Abstract: Résumé: Pour les fluides newtoniens dans des configurations simples, la définition du nombre de Reynolds ne présente aucune difficulté, par contre dans le cas d''écoulement de fluides non newtoniens dans des conduites de formes quelconques, la variation de la viscosité avec la vitesse de cisaillement nécessite une généralisation de ce nombre adimensionnel. Malheureusement plusieurs définitions différentes ont été proposées dans la littérature. Ce travail propose une méthode générale valable pour une large classe de fluides non newtoniens et pour toutes les formes de conduite. Une application est développée pour un fluide viscoélastique s''écoulant dans une conduite de forme rectangulaire. Les résultats obtenus par cette étude sont en bon accord avec les corrélations connues. For Newtonian fluids in simple configurations, the definition of the Reynolds number is quite a standard problem, but for non-Newtonian fluid flows in ducts with arbitrary shape of cross section, the dependence of the viscosity with the shear rate requires a generalization of this dimensionless number, unfortunately several different definitions have been proposed in the literature. This work proposes a general method valid for a large class of non-Newtonian fluids and for all duct shapes. Application is developed for a viscoelastic flow through a rectangular duct. Results obtained in the present investigation are in a good agreement with available correlations. [Copyright &y& Elsevier]

Abstract: The temporal stability of a Carreau fluid flowing down an inclined porous substrate is considered. A reduced model is derived under the assumption of small permeability which decouples the flow in the liquid layer from the filtration flow in the porous medium and incorporates the effect of the porous medium by means of an effective slip condition at the liquid–solid interface. The slip coefficient in the effective slip condition is a function of the structure, permeability of the porous medium and the rheology of the fluid saturating the porous medium. The effects of shear-thinning rheology and permeability of the substrate on the stability of the film flow system are investigated. This problem gives rise to a generalized eigenvalue formulation which is solved through two approaches. The problem is solved analytically for long waves in the limiting cases of weakly and strongly non-Newtonian behaviors (power-law limit). A numerical investigation is carried out in the general case. The results are shown to agree well for the weakly non-Newtonian limit. Further, the power-law model and the Carreau model agree on a wide range of shear-thinning parameter values for a thin film over a rigid substrate. However, when considering a porous medium, this trend is not observed. The Carreau model gives valid results for the entire range of shear-thinning parameter values for a film over a rigid/porous substrate. The novelty of the present investigation lies in the inclusion of both the effects of bottom permeability and shear-thinning rheology. Both permeability and shear-thinning rheology have a destabilizing effect on the film flow system. The numerical results indicate the correlation between the effects due to shear-thinning properties and permeability. An energy balance analysis performed on the perturbation fields shows that destabilization induced by both shear-thinning and permeability is linked to the viscous shear work rate on the free surface. [Copyright &y& Elsevier]

Abstract: An acoustic Strouhal number is introduced to demonstrate that the viscosity of fluid can be ignored in the process of sound propagation and acoustic streaming is independent on the frequency of the acoustic wave. Furthermore, acoustic force based on the periodic velocity fluctuation caused by standing acoustic wave is introduced into Navier–Stokes equation in order to describe the fluid flow in the acoustic boundary layer. The numerical results show that the predicted results are consistent with the analytic solution. And the effect of the nonlinear terms cannot be ignored so the analytic solution derived by boundary-velocity condition is only an approximation for acoustic streaming. [Copyright &y& Elsevier]

Abstract: Aim of the study: An important goal for EEG-based functional brain studies is to estimate the location of brain sources that produce the scalp-recorded signals. Such source localization requires locating precisely the position of the EEG sensors. This review describes and compares different methods that are used for localizing EEG sensors. Results: Five different methods have been described in literature. Manual methods consist in manual measurements to calculate the 3D coordinates of the sensors. Electromagnetic and ultrasound digitization permit localization by using trade devices. The photogrammetry system consists in taking pictures of the patient''s head with the sensors. The last method consists in directly localizing the EEG sensors in the MRI volume. Discussion and conclusions: The spatial localization of EEG sensors is an important step in performing source localization. This method should be accurate, fast, reproducible, and cheap. Currently, electromagnetic digitization is the most currently used method but MRI localization could be an interesting way because no additional method or device needs to be used to locate the EEG sensors. [Copyright &y& Elsevier]

Abstract: Numerical experiments have been performed in order to investigate the convection in an enclosure of aspect ratios 5:1:1.3 subject to a horizontal temperature gradient and a longitudinal sound field. The governing equations are solved by a spectral element method. Different flow structures appear when increasing (or decreasing) the Grashof number. Without acoustic field (acoustic Froude number Fr =0), a hysteresis occurs connected to a first steady bifurcation with breaking of symmetry, but for Fr ≠0, no hysteresis is observed as this symmetry is no more effective. The further transition to oscillatory flow is found to be stabilized by the acoustic field. Depending on Fr, this transition can occur with or without the breaking of the left–right symmetry. [Copyright &y& Elsevier]