Propos d’un géographe climatologue sur les changements climatiques. Une approche, des perspectives

On insiste d’abord sur l’importance de l’échelle synoptique, sur les concordances à ce niveau entre la dynamique des masses d’air et l’organisation spatiale (humaine et sociale) des territoires.Dans le cadre des changements climatiques, on présente les deux volets du concept de potentiel climatique (ressources et risques) avec l’exemple de la pratique française de l’assurance solidaire.On revient enfin sur la question des échelles et des modèles (évoquée en exergue).First, we focus on mesoscale connections between climate patterns (such as the dynamics of air masses) and (human and social) spatial and territorial patterns.Then, the concept of climate potentialities is explained in both of it aspects (resources and risks), and is applied to climatic changes, with the example of French public policies of solidarity insurance.The paper concludes in returning to the topic of spatial scales and climate models, seen earlier

Plant Viruses as Nanoparticle-Based Vaccines and Adjuvants.

International audienceVaccines are considered one of the greatest medical achievements in the battle against infectious diseases. However, the intractability of various diseases such as hepatitis C, HIV/AIDS, malaria, tuberculosis, and cancer poses persistent hurdles given that traditional vaccine-development methods have proven to be ineffective; as such, these challenges have driven the emergence of novel vaccine design approaches. In this regard, much effort has been put into the development of new safe adjuvants and vaccine platforms. Of particular interest, the utilization of plant virus-like nanoparticles and recombinant plant viruses has gained increasing significance as an effective tool in the development of novel vaccines against infectious diseases and cancer. The present review summarizes recent advances in the use of plant viruses as nanoparticle-based vaccines and adjuvants and their mechanism of action. Harnessing plant-virus immunogenic properties will enable the design of novel, safe, and efficacious prophylactic and therapeutic vaccines against disease

The papaya mosaic virus (PapMV) nanoparticles; a promising tool in vaccine development.

There is a major need for the development of new technologies that will facilitate the speed of development of vaccine and show a very high safety profile. In the last 10 years, we have developed a new toll like receptor agonist (TLR) that can trigger innate immunity follow by a strong adaptive immune response. This new agonist targets specifically the TLR7/8 in the endosome of the immune cells. It is made of the coat protein (CP) of a plant virus self-assembled around an RNA that forms flexuous rod-shape nanoparticles of 15x100nm. The highly repetitive and crystalline nature of the nanoparticles are attractive to immune cells leading to its internalization into the endosome where the nanoparticles is broken down by the harsh conditions of this compartment which liberate the RNA that trigger TLR7/8 to induce innate immunity. Therefore, we can use those nanoparticles as an adjuvant and improve the immune response to an antigen or as an immune modulator through the trigger of innate immunity that can induce protection to viral infection or improve the immune response to tumour. Finally, we have showed that we can engineered the nanoparticles into a vaccine platform through fusion of B or T cell epitope at its surface and elicits an efficient and protective immune response to the fused epitope. We will discuss the advantage of using this platform in vaccine development or cancer immunotherapy and show several examples where it has been shoed to be efficient and promising

Cross-validation of ELISA and a portable surface plasmon resonance instrument for IgG antibody serology with SARS-CoV-2 positive individuals.

We report on the development of surface plasmon resonance (SPR) sensors and matching ELISAs for the detection of nucleocapsid and spike antibodies specific to the novel coronavirus 2019 (SARS-CoV-2) in human serum, plasma and dried blood spots (DBS)

Requirement of NOX2 and Reactive Oxygen Species for Efficient RIG-I-Mediated Antiviral Response through Regulation of MAVS Expression

The innate immune response is essential to the host defense against viruses, through restriction of virus replication and coordination of the adaptive immune response. Induction of antiviral genes is a tightly regulated process initiated mainly through sensing of invading virus nucleic acids in the cytoplasm by RIG-I like helicases, RIG-I or Mda5, which transmit the signal through a common mitochondria-associated adaptor, MAVS. Although major breakthroughs have recently been made, much remains unknown about the mechanisms that translate virus recognition into antiviral genes expression. Beside the reputed detrimental role, reactive oxygen species (ROS) act as modulators of cellular signaling and gene regulation. NADPH oxidase (NOX) enzymes are a main source of deliberate cellular ROS production. Here, we found that NOX2 and ROS are required for the host cell to trigger an efficient RIG-I-mediated IRF-3 activation and downstream antiviral IFNβ and IFIT1 gene expression. Additionally, we provide evidence that NOX2 is critical for the expression of the central mitochondria-associated adaptor MAVS. Taken together these data reveal a new facet to the regulation of the innate host defense against viruses through the identification of an unrecognized role of NOX2 and ROS

Climatologie et environnement

Cet article donne un aperçu actuel des données et des méthodes de recherche en climatologie tropicale. Les données météorologiques s’appliquent à la climatologie “actuelle”. Les données utilisées pour l’étude des paléoenvironnements sont d’une autre nature. Dans la zone intertropicale, les données les plus importantes sont les données pluviométriques et les données radiatives (fournies par les radiomètres infrarouges des satellites météorologiques géostationnaires). Les régimes pluviométriques, la nébulosité (convective), sont liés à des échelles spatiales différentes. Ensuite est abordé le problème de la variabilité climatique, spécialement dans l’optique “actualiste”, rendue nécessaire par les besoins économiques à court terme dans de nombreux pays tropicaux (Sahel). Les apports récents de la climatologie dynamique satellitaire et de la climatologie “diagnostique” sont discutés.This paper is an updated view on data and methods in tropical climatology. First, the difference must he made between meteorological data (for present climatology) and proxy data (for palaeoenvironments). In the Tropics, the most important data are rainfall data and energy data (from satellite infrared radiometers). Rainfall rhythms, (convective) cloud patterns are influenced by different spatial scales. Second, climatic variability is shown, in the long term and in the short term. Rural poverty in numerous tropical countries (Sahel) needs precise seasonal weather forecast. But weather and climate are not the same. Results of satellite methods and "diagnostic" global climatology and modelling are discussed

Ambiguïtés tropicales (Tropical ambiguities)

Abstract. - "Tropical ambiguities" appear, when common notions are discussed, as the Climatic Tropical Zone (which puzzles physical geography), or Humid Tropics (a human geographical point of view). Southern China, a region between tropical and temperate areas, is used as sample for the method named "climatic geography", based on climatical potentiality concept.Résumé. - Des «ambiguïtés tropicales» apparaissent en discutant de notions convenues, telles que la zone climatique intertropicale (qui met la géographie physique dans l'embarras) ou les Tropiques humides (issus de la géographie humaine). La Chine du sud, région de transition entre climats tropical et tempéré, sert d'exemple pour un aperçu de «géographie climatique», méthode fondée sur le concept de potentiel climatique.Lamarre Denis. Ambiguïtés tropicales (Tropical ambiguities). In: Bulletin de l'Association de géographes français, 79e année, 2002-4 ( décembre). Villes chinoises. Géoclimatologie, sous la direction de Yves Boquet et Jean-Pierre Vigneau. pp. 450-461

Terroirs et “pays” : Le Bassigny

L’auteur, après avoir décrit l’organisation du relief, examine les évolutions dans la répartition des terroirs et il constate une uniformisation dans l’utilisation du sol.Lamarre Denis. Terroirs et “pays” : Le Bassigny. In: Cahiers du Centre nantais de recherche pour l'aménagement régional, n°43, 1995. Terroirs et Territoires - Travaux de la Commission de Géographie Rurale du Comité National de Géographie. pp. 67-71

Propos d’un géographe climatologue sur les changements climatiques. Une approche, des perspectives

First, we focus on mesoscale connections between climate patterns (such as the dynamics of air masses) and (human and social) spatial and territorial patterns.Then, the concept of climate potentialities is explained in both of it aspects (resources and risks), and is applied to climatic changes, with the example of French public policies of solidarity insurance.The paper concludes in returning to the topic of spatial scales and climate models, seen earlier