University of Perpignan

ABSTRACT This narrative review assesses the effects of repeated sprint training (RST) in hypoxia (RSH) and blood flow restriction (BFR) methods on skeletal muscle adaptations and performance. Current literature suggests that RSH promotes metabolic modifications in muscle cells, especially driven by reactive oxygen species production, HIF-1α stabilization, and changes in metabolism. Training with BFR promotes metabolite accumulation in working muscles due to limited blood flow, however, cellular mechanisms affected by BFR during RST are less explored. Data highlight that RSH improves repeated sprint ability (RSA) in several sport disciplines (e.g. rugby, tennis, soccer, cross-country skiing). However, recent studies showed that addition of hypoxia or BFR during RST did not promote supplementary benefits on aerobic performance, force-velocity power profile, and V ˙ O 2 max . Nonetheless, gains in V ˙ O 2 max were observed during sprint interval training protocols when BFR was applied during recovery between sets. Finally, recent studies highlighted that RSH can improve RSA in a short period. Thus, RSH and sprint training with BFR may be useful for sports disciplines requiring high glycolytic demand and can promote gains in RSA in a short window. Further studies must be encouraged to better understand the biological consequences of adding such stimuli to exercise, especially BFR, on long-term adaptation.

By basing on the same physical model and treatment method, as used in our recent works (Van Cong, 2024; 2023; 2023), we investigate the critical impurity density in the metal-insulator transition (MIT), obtained in the n(p)-type degenerate Si1−xGex- crystalline alloy, 0≤x≤1, and also applied to determine the optical band gap, being due to the effects of the size of donor (acceptor) d(a)-radius, rd(a), the x-Ge concentration, the temperature T, and finally the high d(a)-density, N, assuming that all the impurities are ionized even at T=0 K. In such the n(p)-type degenerate Si1−xGex- crystalline alloy, we will determine: (i)-the critical impurity density

Seedling root traits impact plant establishment under challenging environments. Pearl millet is one of the most heat and drought tolerant cereal crops that provides a vital food source across the sub-Saharan Sahel region. Pearl millet's early root system features a single fast-growing primary root which we hypothesize is an adaptation to the Sahelian climate. Using crop modeling, we demonstrate that early drought stress is an important constraint in agrosystems in the Sahel where pearl millet was domesticated. Furthermore, we show that increased pearl millet primary root growth is correlated with increased early water stress tolerance in field conditions. Genetics including genome-wide association study and quantitative trait loci (QTL) approaches identify genomic regions controlling this key root trait. Combining gene expression data, re-sequencing and re-annotation of one of these genomic regions identified a glutaredoxin-encoding gene PgGRXC9 as the candidate stress resilience root growth regulator. Functional characterization of its closest Arabidopsis homolog AtROXY19 revealed a novel role for this glutaredoxin (GRX) gene clade in regulating cell elongation. In summary, our study suggests a conserved function for GRX genes in conferring root cell elongation and enhancing resilience of pearl millet to its Sahelian environment.

We investigated the evolutionary history of the grey reef shark (Carcharhinus amblyrhynchos) in the Indo-Pacific (IP) by harnessing the power of thousands of RAD-seq loci sequenced in 175 individuals across its range. We bring strong evidences of the occurrence of a range expansion (RE) originating close to the Indo-Australian Archipelago (IAA) from which two stepping-stone waves (east and westward) started, colonizing almost the entire IP. Consequently, the demographic history of C. amblyrhynchos is best explained by a meta-population model, for which we estimated a homogenous connectivity throughout its range (Nm~10 per generation) by means of coalescent modeling coupled with an Approximate Bayesian Computation framework. An isolation by distance model further highlights the absence of either genetic barriers or preferential migration corridors, despite the dependency of C. amblyrhynchos from coral reefs occurrence. This is consistent with the long-distance swims observed, suggesting that the strong genetic structure at the IP scale (F~0.56 between its ends) is rather the consequence of its large current distribution. We contrasted these results with those previously obtained for the sympatric but strictly lagoon-associated Carcharhinus melanopterus, a species well known for its restricted dispersal ability. While C. melanopterus exhibits a similar RE dynamic, it is characterized by stronger genetic structure and a non-homogeneous connectivity largely dependent on local coral reefs availability. The comparison between the two species sheds new light on shark evolution, emphasizing the role of IAA as source of biodiversity and of dispersal ability in shaping the extent of population structure and genetic diversity.

International audience

S’està acabant aquests dies “l’any Badia”, any del centenari del seu naixement a Barcelona, allà on va estudiar, ensenyar, investigar i publicar i on es va morir amb 94 anys, deixant una petjada majúscula en el món universitari i fins i tot a la ciutadania de Catalunya i dels Països Catalans. Jo, com a sociolingüista que mai el va conèixer en vida, però que va descobrir els seus escrits els anys 80 del segle passat, no cal dir com em plau de participar a aquesta Jorn

In the n + (p + ) − p(n) crystalline ( X ≡Ge, GaSb, CdTe or CdSe)-junction solar cells at 300K, due to the effects of impurity size, temperature, heavy doping, and photovoltaic conversion, we show that, with an increasing donor (acceptor)-radius r d a , both the relative dielectric constant and photovoltaic conversion factor decrease, and the intrinsic band gap (IBG) increases, according to the increase in photovoltaic efficiency, as observed in Tables 1-5 , being in good accordance with an important result obtained by Shockley and Queisser [10], stating that for an increasing IBG the photovoltaic efficiency increases. Further, for highest values of r d a , the limiting highest efficiencies are found to be given in Tables 2.2, 3.2, 4.2, and 5.2, as: 14.82 %, 12.16 %, 26.55 %, and 23.69 %,), obtained in such n + (p + ) − p(n) crystalline (Ge, GaSb, CdTe, or CdSe)-junction solar cells at the open circuit voltage =0.33 V, 0.355 V, 0.82 V, and 0.89 V, respectively, and at T=300 K. Furthermore, from the well-known Carnot-efficiency theorem, as given in Eq. ( 46), being obtained from the second principle of the thermodynamics, and from the above results of limiting highest efficiencies, the corresponding highest hot reservoir temperatures, T H =352.2 K, 341.5 K, 408.4 K, and 393.1 K, respectively. Thus, as noted above, η max. and T H both increase with an increasing IBG, for each (X≡Ge, GaSb, CdTe, or CdSe)-crystal at T=300 K≡ T C .