In this paper, we consider a Kirchhoff-type visco elastic equation with nonlinear damping and source terms involving variable exponents. We establish results on the blow-up and exponential growth of solutions corresponding to negative initial energy.
Tyrosinase, a copper-containing enzyme with broad biological and industrial applications, occurs widely in nature but remains underexplored in edible mushrooms such as Agaricus bisporus. This study reports the extraction, purification, and biochemical characterization of tyrosinase from A. bisporus fruiting bodies. The enzyme was purified via ammonium sulfate precipitation (60
We consider a smooth pessimistic bilevel optimization problem, where the lower-level problem is convex and satisfies the Slater constraint qualification. These assumptions ensure that the Karush-Kuhn-Tucker (KKT) reformulation of our problem is well-defined. We then introduce and study the (i) Scholtes, (ii) Lin and Fukushima, (iii) Kadrani, Dussault and Benchakroun, (iv) Steffensen and Ulbrich, and (v) Kanzow and Schwartz relaxation methods for the KKT reformulation of our pessimistic bilevel program. These relaxations have been extensively studied and compared for mathematical programs with complementarity constraints (MPCCs). To the best of our knowledge, such a study has not been conducted for the pessimistic bilevel optimization problem, which is completely different from an MPCC, as the complementarity conditions are part of the objective function, and not in the feasible set of the problem. After introducing these relaxations, we provide convergence results for global and local optimal solutions, as well as suitable versions of the C- and M-stationarity points of our pessimistic bilevel optimization problem. Numerical results are also provided to illustrate the practical implementation of these relaxation algorithms, as well as some preliminary comparisons.
Abstract Background Parkinson’s disease (PD), a complex neurodegenerative disorder, is increasingly prevalent, with a strong genetic component. While environmental factors contribute, the exact cause remains elusive. Understanding PD’s genetic basis is vital for advancing research and treatment. This study seeks to investigate the genetic diversity of Parkinson’s disease in the Algerian population using whole exome sequencing (WES), with the goal of identifying rare variants across genes potentially associated with the disease. Methods Whole exome sequencing (WES) was performed on a cohort of 19 Algerian patients with clinically confirmed Parkinson’s disease, including 8 patients with a positive family history. Variant annotation and functional effect prediction were performed using SnpEff, in conjunction with multiple reference genomic databases. Variant calling results were stored in Variant Call Format (VCF). Variants were classified according to their minor allele frequency (MAF): rare variants were defined as those with a MAF between 0.1% and 1%, while novel variants were defined as those with a MAF ≤ 0.1% or absent from all queried reference databases. Results Whole exome sequencing analysis identified 73 variants distributed across 22 genes in 19 Algerian patients with Parkinson’s disease. Following prioritization, nine variants were detected across six candidate genes ( DDOST , AUP1 , SNORD66 , TRPM7 , ORC6 , and GLUD2 ), whose association with Parkinson’s disease had not been previously reported in North African populations. These genes are involved in several cellular functions, including protein homeostasis, DNA repair, cellular metabolism, and oxidative stress response. Among them, GLUD2 emerges as a particularly compelling candidate requiring functional validation for future investigations. Conclusion This preliminary study highlights the genetic diversity of Parkinson’s disease in the Algerian population and underscores the value of whole exome sequencing for the identification of rare variants in underrepresented populations. The findings suggest potential novel research avenues that may contribute to expanding knowledge of the genetic architecture of the disease. Replication studies and functional validation will be required to confirm the biological and clinical relevance of the identified variants.
Introduction Les pathologies émergentes constituent un défi croissant pour les systèmes de santé, en lien avec les transformations rapides des environnements professionnels, sociaux et environnementaux. En Algérie, les mutations industrielles, l’urbanisation, les changements climatiques et l’introduction de nouvelles technologies exposent les populations à des risques émergents insuffisamment documentés. L’identification précoce de ces pathologies représente un enjeu majeur de santé publique et de médecine du travail. Méthodologie Une analyse descriptive et synthétique a été réalisée à partir de données issues de la littérature scientifique, de rapports institutionnels et d’observations de terrain en santé publique et en santé au travail en Algérie. Les pathologies émergentes ont été abordées selon une approche intégrée tenant compte des risques environnementaux, professionnels, technologiques et organisationnels. Résultats Les principales pathologies émergentes identifiées concernent les maladies respiratoires liées à la pollution atmosphérique, les troubles musculosquelettiques associés aux nouvelles organisations du travail, les pathologies psychosociales liées à l’intensification du travail, ainsi que certaines affections chroniques liées aux expositions chimiques et physiques émergentes. Parallèlement, de nouveaux risques professionnels ont été mis en évidence, notamment ceux liés aux nanomatériaux, aux agents chimiques de substitution, aux technologies numériques et aux contraintes climatiques extrêmes. Discussion Ces résultats traduisent une transition des risques vers des expositions plus diffuses, cumulatives et évolutives, souvent mal prises en compte par les dispositifs classiques d’évaluation. Le caractère non spécifique et parfois différé des pathologies émergentes complique leur détection précoce. En Algérie, cette situation est accentuée par l’hétérogénéité des secteurs d’activité et l’introduction progressive de nouvelles technologies sans anticipation suffisante de leurs impacts sanitaires. Le développement de la veille sanitaire, le renforcement de la surveillance épidémiologique et une meilleure articulation entre santé publique et santé au travail apparaissent essentiels, notamment pour adapter les politiques de prévention aux réalités locales et aux transformations rapides des environnements de travail. Conclusion En Algérie, les pathologies et risques émergents imposent une adaptation des stratégies de prévention, de surveillance et de formation en santé publique et en santé au travail. Le renforcement de la recherche, la structuration de systèmes de veille et l’approche pluridisciplinaire constituent des leviers majeurs pour répondre à ces nouveaux enjeux sanitaires.
