Modeling and Thermodynamic Study of Water Vapor Desorption Isotherms of Orange Peel and Leaves using Statistical Physics Treatment

The shelf life and safety of food products is related to the water content, in particular to the water activity (aw). This is important to predict the physical, chemical and biological processes that take place during food storage. Analytical expression for modeling water desorption isotherms of food is developed using the grand canonical ensemble in statistical physics. The model is further applied to fit and interpret the desorption isotherms of water vapor on the orange peel and leaves at three different temperatures. In the developed model we introduce essentially six parameters such as the number of adsorbed water molecules per site, the number of adsorbed layers, the energy of desorption and receptor sites density. We interpret the results of fitting then we apply the model to calculate thermodynamic functions which govern the desorption mechanism such as internal energy and entropy

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Electrokinetic behaviour of kaolin-smectite samples

Ce travail de thèse a permis de se focaliser sur le traitement électrocinétique d’un sol argileux. Le but consiste alors à étudier l’évolution de la structure des mélanges de kaolinite + smectite pollués avec du plomb après un traitement électrocinétique. Il s’agit d’appréhender les éventuelles variations des propriétés mécaniques des sols après l’électrocinétique. Du point de vue de la structure, de façon générale de faibles variations de la porosité (porosimétrie au mercure) ont été observées après le traitement électrocinétique.This thesis work focused on the electrokinetic treatment of clay soil. The aim is to study the evolution of the structure of kaolinite + smectite mixtures polluted with lead after an electrokinetic treatment. The aim is to understand the possible variations in the mechanical properties of soils after electrokinetics. From a structural point of view, generally small variations in porosity (mercury porosimetry) were observed after the electrokinetic treatment

Comportement électrocinétique de mélanges kaolinite-smectite

This thesis work focused on the electrokinetic treatment of clay soil. The aim is to study the evolution of the structure of kaolinite + smectite mixtures polluted with lead after an electrokinetic treatment. The aim is to understand the possible variations in the mechanical properties of soils after electrokinetics. From a structural point of view, generally small variations in porosity (mercury porosimetry) were observed after the electrokinetic treatment.Ce travail de thèse a permis de se focaliser sur le traitement électrocinétique d’un sol argileux. Le but consiste alors à étudier l’évolution de la structure des mélanges de kaolinite + smectite pollués avec du plomb après un traitement électrocinétique. Il s’agit d’appréhender les éventuelles variations des propriétés mécaniques des sols après l’électrocinétique. Du point de vue de la structure, de façon générale de faibles variations de la porosité (porosimétrie au mercure) ont été observées après le traitement électrocinétique

Effet d’un traitement électrocinétique sur la structure d’une kaolinite mélangée au carbonate

International audienceThe aim of this work is to study the structure evolution of kaolinite + carbonate mixture after an electrokinetic treatment. The aim is to understand how an electrokinetic treatment can change the mechanical properties of the samples. The X-rays diffraction analysis show that the orientation of the particles and their size depend on the composition of the samples and to the presence of lead. The mercury intrusion tests show that the porosity vary slightly after the electrokinetic treatment.Le but de ce travail est d’étudier l’évolution de la structure de mélange de kaolinite + carbonate après un traitement électrocinétique. Le but étant d’appréhender les éventuelles variations des propriétés mécaniques des sols après l’électrocinétique. La diffraction des rayons X montre que l’orientation des particules et leur taille dépend de la composition du sol et de la présence du plomb. La porosimétrie au mercure a montré une faible variation de la porosité

Effet d’un traitement électrocinétique sur la structure d’une kaolinite mélangée au carbonate

International audienceThe aim of this work is to study the structure evolution of kaolinite + carbonate mixture after an electrokinetic treatment. The aim is to understand how an electrokinetic treatment can change the mechanical properties of the samples. The X-rays diffraction analysis show that the orientation of the particles and their size depend on the composition of the samples and to the presence of lead. The mercury intrusion tests show that the porosity vary slightly after the electrokinetic treatment.Le but de ce travail est d’étudier l’évolution de la structure de mélange de kaolinite + carbonate après un traitement électrocinétique. Le but étant d’appréhender les éventuelles variations des propriétés mécaniques des sols après l’électrocinétique. La diffraction des rayons X montre que l’orientation des particules et leur taille dépend de la composition du sol et de la présence du plomb. La porosimétrie au mercure a montré une faible variation de la porosité

Clinical and Epidemiological Profile of Reversible Acute Kidney Injury with Full Recovery: Experience of a Nephrology Department

Purpose: Acute kidney injury (AKI) is a real public health problem due to its severity and gravity. In a 2013 meta-analysis, Susantitaphong, et al. estimated the incidence of AKI worldwide at between 10% and 20%. In the latter study, no African studies were included, given the lack of data in the literature. Our objective was to identify the clinical and paraclinical epidemiological characteristics of patients with AKI.Patients and methods: We conducted a retrospective study including patients who had AKI with recovery of normal renal function hospitalized in a nephrology service between 2002 and 2015.Results: Our population consisted of 107 men and 107 women with a median age of 61 years (IQR 43-73.25) of which 42.1% were multitargeted. Functional AKI represented the predominant mechanism of AKI retained in our study with a rate of 53.2% with dehydration as the main etiology for 108 patients (50.46%). Organic cause was retained in 38.8% of patients, with acute tubular necrosis (ATN) as the most frequent etiology (37.35%). Kidney disease improving global outcomes (KDIGO) stage 3 was the stage retained for 115 patients included in our series, 31 of whom required extra renal purification. During their hospitalization, 78.5% of the patients presented a persistent AKI (duration of the episode > 7 days). A glomerular filtration rate (GFR) lower than 60 ml/min/1.73 m² at discharge was found in 119 patients and 10 patients had a GFR higher than 90 ml/min/1.73 m². After 3 months from discharge, 77.5% of patients had a GFR between 60 and 90 ml/min/1.73 m².Conclusion: Our results give us an idea of the epidemiological and clinical characteristics of patients who have had acute renal failure with recovery of normal renal function and enable us to better recognize patients at risk in order to avoid such complications. AKI remains a major issue and knowing its epidemiological and clinical characteristics will allow its prevention

The Clinical Features and Outcomes of Renal Amyloidosis in Tunisia

Systemic amyloidosis is a rare disease characterized by clinical polymorphism. Indeed, the kidney is the most common organ involved and represents a real turning point in the disease. We aimed to determine the clinicopathological prognostic factors of renal amyloidosis (RA). We conducted a retrospective study including 40 cases with biopsy-proven RA collected in our department over a period of 10 years. Biochemical, demographic, and clinicopathological findings at diagnosis, as well as the follow-up data, were evaluated for each patient. The prevalence of amyloidosis was 2.7 per 100 nontransplant renal biopsies. The mean age at presentation was 55.5 ± 15.6 years with a male-to-female ratio of 1.85. The diagnosis of RA was confirmed by a renal biopsy in 85% of cases. Amyloid A (AA) amyloidosis was the most common type of amyloidosis (65%), and chronic infections ranked first in the panel of etiologies (41%). Amyloid light chain amyloidosis was mainly associated with multiple myeloma (57%). The median patient survival was 59 months versus 12 months for kidney survival. Age and extrarenal localization were independent predictors of mortality, whereas renal failure at presentation significantly influenced renal survival. The results of our study emphasize the rarity but also the severity of RA. AA amyloidosis was the most common type identified, which was mainly caused by chronic infections. Prevention remains the best solution until we can achieve therapeutic advances in inflammatory diseases

Date Fiber Concentrate: Chemical Compositions, Functional Properties and Effect on Quality Characteristics of Beef Burgers

Chemical composition of second-grade dates (with hard texture) from Tunisian Deglet Nour cultivar was similar to that of commercial dates. Date fiber concentrate (DFC) was extracted and characterized in terms of chemical composition and techno-functional properties. DFC showed interesting functional properties. In fact, it presented high water binding capacities (WBC) and oil binding capacities (OBC) reaching 15.82 g/g and 11.31 g/g, respectively. These Values were higher than those reported for the most fruits and vegetable fiber concentrates. The use of DFC in beef burger formulations improves cooking properties, e.g. increase cooking yield and decrease shrinkage and minimize production Cost Without negatively affecting their sensory properties. Results indicate the potentially functional and economic utility Of Phoenix L. Flesh from dry dates as new source of dietary fiber