50 research outputs found
Відділення фізики і астрономії Національної академії наук України
Developmental changes in myofibrillar protein composition were investigated in the myotomal muscle of the African catfish, Heterobranchus longifilis (Clariidae), by several electrophoretic techniques. The main muscle fibres of larvae and the fast-white muscle fibres of juvenile and adult fish were found to express distinct myosin heavy chain and myosin light chain 2 (LC2) isoforms. Three myosin LC2 chains were successively detected, differing by their isoelectric points. In contrast, the alkali light chains remained qualitatively and quantitatively unchanged during fish growth. Actin, α-tropomyosin, and troponin-C (TN-C) were also similar in larval, juvenile, and adult white muscle, but an additional larval tropomyosin isoform was found in the first developmental stages. Two isoforms of troponin-T (TN-T) and troponin-I (TN-I) were synthesised in the course of fish growth. Transition from the larval to the adult isoform was much faster for TN-T than for TN-I. Slow-red muscle myofibrils from adult H. longifilis showed no common component (except actin) with larval, juvenile, or adult fast-white muscle myofibrils. Red myofibrils displayed a single TN-T and a single TN-I isoform, but two isoforms of TN-C. The myofibrillar protein isoforms synthesised at any given developmental stage almost certainly reflect changes in the functional requirements of swimming muscles in the course of fish development
Forces Generated by the Free Fall of DEMICHAIN
The free fall of an array of heavy chains (360 kg/sq m) generates extensive pressure in the depth of the ground. These pressures have been measured and compared to the threshold pressures that trigger anti-personnel landmines. When dropped from moderate heights (1 m), chains can generate enough pressure to set off active landmines buried 20 cm, provided that the area of their pressure plates is larger than a few square centimeters
Kinetics of adsorption of linear and branched C6 alkanes onto ZSM-5 zeolite - experiments and molecular simulations: Kinetics of adsorption of linear and branched C6 alkanes ontoZSM-5 zeolite - experiments and molecular simulations
Main Recent Contributions to SHS from France
International audienceBoth in situ TRXRD and IR thermography, on the one hand, and different levels of modeling, on the other, have generated a strong progress in the knowledge and control of numerous SHS reactions. The SHS of simple binary materials, such as intermetallics (FeAl, MoSi2, NbAl3, etc.), oxides (e.g. ZrO2), carbides (e.g. SiC) or nitrides, more complex materials, such as mullite, SiAlONs, MAX phases, composites (SiO2-Al2O3, NiAl-ZrO2 ), powders in their more complicated states, such as well controlled microstructures, fully densified intermetallics, smart composites, and hard coatings carried out by GFA researchers greatly contributed to the worldwide competition to harness the potential of SHS. On the occasion of the 40th anniversary of SHS, this paper is giving an overview of the main results obtained by GFA over the last ten years
Lattice Gas Automata for Reactive Systems
Reactive lattice gas automata provide a microscopic approachto the dynamics
of spatially-distributed reacting systems. After introducing the subject within
the wider framework of lattice gas automata (LGA) as a microscopic approach to
the phenomenology of macroscopic systems, we describe the reactive LGA in terms
of a simple physical picture to show how an automaton can be constructed to
capture the essentials of a reactive molecular dynamics scheme. The statistical
mechanical theory of the automaton is then developed for diffusive transport
and for reactive processes, and a general algorithm is presented for reactive
LGA. The method is illustrated by considering applications to bistable and
excitable media, oscillatory behavior in reactive systems, chemical chaos and
pattern formation triggered by Turing bifurcations. The reactive lattice gas
scheme is contrasted with related cellular automaton methods and the paper
concludes with a discussion of future perspectives.Comment: to appear in PHYSICS REPORTS, 81 revtex pages; uuencoded gziped
postscript file; figures available from [email protected] or
[email protected]
SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues
Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to
genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility
and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component.
Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci
(eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene),
including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform
genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer
SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the
diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types