Electrochemical performances of vitreous materials in the system Li2O–V2O5–P2O5 as electrode for lithium batteries

International audienceGlass composition 25Li2O–50V2O5–25P2O5 has been investigated as a potential material for electrode. Electrical properties as well as electrochemical performances of this glass composition have been characterized and results show a capacity less than 80mAhg−1 when tested in the [3–4.5V] potential window. To the best of our knowledge, this is the first lithiated amorphous material reported as a potential positive electrode material. Glasses, due to their wide available compositions in a given system and their easy processing, pave the way to new type of electrode material

Time-restricted feeding improves adaptation to chronically alternating light-dark cycles

Disturbance of the circadian clock has been associated with increased risk of cardio-metabolic disorders. Previous studies showed that optimal timing of food intake can improve metabolic health. We hypothesized that time-restricted feeding could be a strategy to minimize long term adverse metabolic health effects of shift work and jetlag. In this study, we exposed female FVB mice to weekly alternating light-dark cycles (i.e. 12 h shifts) combined with ad libitum feeding, dark phase feeding or feeding at a fixed clock time, in the original dark phase. In contrast to our expectations, long-term disturbance of the circadian clock had only modest effects on metabolic parameters. Mice fed at a fixed time showed a delayed adaptation compared to ad libitum fed animals, in terms of the similarity in 24 h rhythm of core body temperature, in weeks when food was only available in the light phase. This was accompanied by increased plasma triglyceride levels and decreased energy expenditure, indicating a less favorable metabolic state. On the other hand, dark phase feeding accelerated adaptation of core body temperature and activity rhythms, however, did not improve the metabolic state of animals compared to ad libitum feeding. Taken together, restricting food intake to the active dark phase enhanced adaptation to shifts in the light-dark schedule, without significantly affecting metabolic parameters

The Cryptosporidium parvum Kinome

<p>Abstract</p> <p>Background</p> <p>Hundreds of millions of people are infected with cryptosporidiosis annually, with immunocompromised individuals suffering debilitating symptoms and children in socioeconomically challenged regions at risk of repeated infections. There is currently no effective drug available. In order to facilitate the pursuit of anti-cryptosporidiosis targets and compounds, our study spans the classification of the <it>Cryptosporidium parvum </it>kinome and the structural and biochemical characterization of representatives from the CDPK family and a MAP kinase.</p> <p>Results</p> <p>The <it>C</it>. <it>parvum </it>kinome comprises over 70 members, some of which may be promising drug targets. These <it>C. parvum </it>protein kinases include members in the AGC, Atypical, CaMK, CK1, CMGC, and TKL groups; however, almost 35% could only be classified as OPK (other protein kinases). In addition, about 25% of the kinases identified did not have any known orthologues outside of <it>Cryptosporidium spp</it>. Comparison of specific kinases with their <it>Plasmodium falciparum </it>and <it>Toxoplasma gondii </it>orthologues revealed some distinct characteristics within the <it>C. parvum </it>kinome, including potential targets and opportunities for drug design. Structural and biochemical analysis of 4 representatives of the CaMK group and a MAP kinase confirms features that may be exploited in inhibitor design. Indeed, screening <it>Cp</it>CDPK1 against a library of kinase inhibitors yielded a set of the pyrazolopyrimidine derivatives (PP1-derivatives) with IC₅₀values of < 10 nM. The binding of a PP1-derivative is further described by an inhibitor-bound crystal structure of <it>Cp</it>CDPK1. In addition, structural analysis of <it>Cp</it>CDPK4 identified an unprecedented Zn-finger within the CDPK kinase domain that may have implications for its regulation.</p> <p>Conclusions</p> <p>Identification and comparison of the <it>C. parvum </it>protein kinases against other parasitic kinases shows how orthologue- and family-based research can be used to facilitate characterization of promising drug targets and the search for new drugs.</p

Le frittage flash (SPS) (de la réactivité à l'assemblage de batteries "tout solide")

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Structural investigation in monolithic silica aerogels and thermal properties

International audienceThe influence, of the number of water molecules (n*) used to synthesize polyethoxydisiloxane (PEDS-Px) silica precursors, on the internal structure of aerogels made with those precursors in ethylacetoacetate (etac) under HF conditions and dried under CO2 supercritical conditions was studied. Gas adsorption, water thermoporometry and mercury porosimetry were used to characterize specific area and pore size distribution. The results were used to interpret the evolution of the apparent thermal conductivity of those aerogels with n*. Optical transmission was also measured to estimate optical quality of the aerogels prepared

The negative effect of wood ant presence on tick abundance

Abstract Background Ticks and tick-borne pathogens are a global problem for the health of humans and their livestock. Wood ants are important ecosystem engineers in forests worldwide. Although both taxa are well studied, little is known about their interactions under natural conditions. The purpose of the present field study was to test whether European red wood ants (Formica polyctena) influence the abundance of Ixodes tick populations in temperate forests. Methods Data collection took place in 130 sampling plots located at 26 ant nest sites paired with 26 control sites in northwestern Switzerland. At each sampling plot, tick abundance, ant abundance, ant nest volume and habitat variables (describing litter, vegetation and microclimate) were measured. We used linear mixed-effect models to analyze the abundance of questing ticks as a function of ant abundance and habitat variables. Results Ant nest volume, rather than the presence of ants, had a significant negative effect on tick abundance. The number of ticks decreased from 11.2 to 3.5 per 100 m2 if the volume of the adjacent ant nest increased from 0.1 m3 to 0.5 m3. Additionally, high vegetation cover and litter depth had negative and positive relationships with tick abundance, respectively. Conclusions We showed that the number of questing ticks was negatively correlated with the size of red wood ant nests. Further studies are needed to identify the mechanisms that drive the relationship. Possible mechanisms include the repellent effect of ant formic acid, and the predatory behavior of wood ants. The present field study suggests that red wood ants provide a new ecosystem service by reducing the local abundance of Ixodes ticks

Élaboration d'aérogels monolithiques de silice et étude des relations entre leur structure et leur conductivité thermique équivalente mesurée en régime transitoire par la méthode de la sonde à choc

International audienc

Elaboration et étude des relations entre la structure et les propriétés thermiques d'aérogels monolithiques de silice

National audienc