Showing papers by "University of Montpellier published in 1995"
15,729 citations
TL;DR: Ageing of large size plates and millimetric beads showed that devices with dimensions smaller than the thickness of the outer layer should degrade less rapidly than larger ones, and heterogeneously and faster than homogeneously degraded submillimetric films and particles.
852 citations
TL;DR: Different exact tests, appropriate for small sample size and large number of alleles, are proposed in this perspective, and their properties are evaluated by power comparisons.
Abstract: Currently used tests of Hardy-Weinberg proportions do not take into account the nature of the alternative hypothesis, which is generally a heterozygote deficiency. Different exact tests, appropriate for small sample size and large number of alleles, are proposed in this perspective, and their properties are evaluated by power comparisons. Some tests are found to be close to optimal for the detection of inbreeding or heterozygote excess, one of which is a score test closely related to Robertson and Hill's estimator of the inbreeding coefficient. This test is also easily applied to multiple samples. Such tests are not always the most appropriate if alternative hypotheses differ from those considered here.
792 citations
TL;DR: Taking into account the baroprotective effects of some food constituents and the strong resistance of some microbial strains, recent research aims at combined processes in which high pressure is associated with moderate temperature, CO2, other bacteriostatic agents, or to nonthermal physical processes such as ultrasounds, alternative currents, high-voltage electric pulses, and so forth.
Abstract: High pressure (1 to 10 kbars, i.e. 100-1000 MPa) affects biological constituents and systems. Several physicochemical properties of water are modified, such as the density, the ionic dissociation (...
727 citations
TL;DR: In this article, a three-layer model of the continental lithosphere is used to model the subduction process of the Himalayas, and the results of the modelling are tested on the example of the Mt. Kilimanjarvis.
499 citations
TL;DR: In this article, minced beef was packaged under vacuum, air or oxygen, and pressurized at 10°C for 10 min, and the results showed that L* colour values increased significantly in the range 200-350 MPa, the meat becoming pink, while a* values decreased at 400-500 MPa.
Abstract: Minced beef meat was packaged under vacuum, air or oxygen, and pressurized at 10°C for 10 min. L* colour values increased significantly in the range 200–350 MPa, the meat becoming pink, while a* values decreased at 400–500 MPa, the meat becoming grey-brown. Simultaneously, total extractible myoglobin decreased in the range 200–500 MPa, while the proportion of metmyoglobin increased at the expense of oxymyoglobin at 400–500 MPa. Pressurization did not significantly increase the extractibility of heme iron by an acid solution. Packaging of meat under vacuum with an oxygen scavenger partly protected meat colour, since samples processed at 400 MPa became pink, without any change in a* value or metmyoglobin content. Blending chilled minced meat with NaNo 2 (and NaCl) 18 h before processing at 350–500 MPa afforded a similar protection. Cysteine, ascorbic acid, nicotinamide or nicotinic acid had no protective effects. Meat discoloration through pressure processing may result from (1) a whitening effect in the range 200–350 MPa, due to globin denaturation and/or to heme displacement or release, and (2) oxidation of ferrous myoglobin to ferric metmyoglobin, at or above 400 MPa. Only the latter phenomenon is prevented by total oxygen removal or prior formation of nitrosomyoglobin.
312 citations
TL;DR: The Borborema shear zone system is coeval with a high-temperature, medium-to low-pressure metamorphism, partial melting of the crust, and synkinematic magmatism involving both crustal and mantle-derived magmas as discussed by the authors.
287 citations
TL;DR: This investigation leads to revision of the previous modelings based on quasicubic descriptions of the valence-band physics and gives a set of deformation potentials for the hexagonal GaN semiconductor.
Abstract: We report on a quantitative analysis of the band gap of hexagonal GaN epilayers in terms of the joint contributions of the actual wurtzite symmetry on the one hand and of residual strain fields on the other hand. This investigation leads to revision of the previous modelings based on quasicubic descriptions of the valence-band physics and gives ${\mathrm{\ensuremath{\Delta}}}_{1}$=10\ifmmode\pm\else\textpm\fi{}0.1 meV, ${\mathrm{\ensuremath{\Delta}}}_{2}$=6.2\ifmmode\pm\else\textpm\fi{}0.1 meV, and ${\mathrm{\ensuremath{\Delta}}}_{3}$=5.5\ifmmode\pm\else\textpm\fi{}0.1 meV. Last we propose a set of deformation potentials for the hexagonal GaN semiconductor.
263 citations
TL;DR: The synthesis, in vitro anti-HIV-1 activity, and decomposition pathways of several mononucleoside phosphotriester derivatives of 3'-azido-2',3'-dideoxythymidine incorporating a new kind of carboxylate esterase-labile transient phosphate-protecting group, namely, S-acyl-2-thioethyl are reported.
Abstract: The synthesis, in vitro anti-HIV-1 activity, and decomposition pathways of several mononucleoside phosphotriester derivatives of 3'-azido-2',3'-dideoxythymidine (AZT) incorporating a new kind of carboxylate esterase-labile transient phosphate-protecting group, namely, S-acyl-2-thioethyl, are reported. All the described compounds showed marked antiviral activity in thymidine kinase-deficient CEM cells in which AZT was virtually inactive. The results strongly support the hypothesis that such pronucleotides exert their biological effects via intracellular delivery of the 5'-mononucleotide of AZT. This point was corroborated by decomposition studies in cell extracts and culture medium.
258 citations
249 citations
TL;DR: RLI appears as the first described and potentially important mediator of the 2-5A/RNase L pathway, a new type of endoribonuclease inhibitors of interferon (IFN) action.
TL;DR: It is shown that steroid saponins enhance food consumption and motivation to eat, and reduce plasma cholesterol levels in rats, which resulted in a progressive weight gain in these animals, in contrast to untreated diabetic controls.
TL;DR: In this paper, the effects of protein concentration, pH, temperature and storage time before casting on the apparent viscosity of the film forming solution (FFS) were evaluated using experimental design methodology.
Abstract: Biopackaging materials based on fish myofibrillar proteins have been developed. The effects of protein concentration, pH, temperature and storage time before casting on the apparent viscosity of the film forming solution (FFS) were evaluated using experimental design methodology. The first objective was to determine a feasible experimental range for film-forming. The pH and protein concentration had strong interactive effects on FFS viscosity. During FFS storage before casting, partial degradation of high molecular weight protein components led to decreased viscosity, allowing thin layer casting. In the experimental range for film-forming, none of the conditions affected film functional properties. Standard conditions were determined at: pH 3.0, 2.0g protein/100g FFS, 25°C and 6 hr storage. The functional properties of the standard biopackaging were slightly better than those that determined for known protein-based films, with tensile strength close to those of low density polyethylene films.
TL;DR: It is shown, that a purified N‐terminal glutathione S‐transferase (GST) fusion protein of ezrin still has retained the capacity to interact with PIP2‐containing liposomes, whereas a C-terminal fusion protein has lost this ability.
TL;DR: Recent information on molluscs and crustaceans is presented, concerning both hemocyte studies and cellular defence functions and humoral effectors, with special reference to their application to selection of pathogen-resistant animals.
TL;DR: Although the environmental conditions of the specific area of cultivation seem to play a role in the formation of fumonisin in maize, further investigations are needed to thoroughly establish the genotype-area-season interaction.
Abstract: The natural occurrence of fumonisin B-1 (FB1) and fumonisin B-2 (FB2) has been investigated in 26 maize inbred lines grown in Italy and in 72 maize hybrids grown in Croatia (19), Poland (7), Portugal (9), Romania (6), Benin (9), and Zambia (20). The incidence and levels of fumonisin contamination resulted in two major groups of countries. The first with high contamination included Italy, Portugal, Zambia, and Benin, with incidence of 100, 100, 100, and 82%, and fumonisin (FB1 + FB2) levels up to 2850, 4450, 1710, and 3310 ng/g, respectively. The second group, including Croatia, Poland, and Romania, showed very low levels of contamination (less than or equal to 70 ng/g) with 50% incidence of positive samples. A general trend for higher contamination levels was observed in maize genotypes with higher FAO maturity class or dent-type endosperm. Although the environmental conditions of the specific area of cultivation seem to play a role in the formation of fumonisin in maize, further investigations are needed to thoroughly establish the genotype-area-season interaction.
TL;DR: This article focuses on the hypertext 1 design task itself as a computer-supported activity and provides guidelines for developers of hypermedia design environments to facilitate the user's design process.
TL;DR: The development of class climate scales in French and English for use in physical education classes was shown to be satisfactory, including adequate factorial structure assessed by exploratory and confirmatory factor analysis (CFA), and good internal and test-retest reliability.
Abstract: Motivational research in the classroom has adopted a social cognitive perspective but has mainly been restricted to the study of individual achievement cognitions. In addition to this, there is a need to study and assess the perception children have of the class climate. Using social cognitive theory as a base, this research reports the development of class climate scales in French and English for use in physical education classes. Psychometric development with the French scale was shown to be satisfactory, including adequate factorial structure assessed by exploratory and confirmatory factor analysis (CFA), and good internal and test-retest reliability. A parallel English scale demonstrated a less adequate fit to the proposed model when using CFA, but shortened scales assessing just mastery and performance dimensions of climate were shown to predict important motivational measures in a structural equation modelling analysis.
TL;DR: In this article, the authors used in-situ-produced 10 Be to calculate minimum ages for alluvial surfaces misaligned by movement along a major active fault in the Gobi-Altai (western Mongolia).
Abstract: Dating morphological features displaced along active faults presents a major difficulty in evaluation of slip rates. We used in-situ–produced 10 Be to calculate minimum ages for alluvial surfaces misaligned by movement along a major active fault in the Gobi-Altai (western Mongolia). The maximum slip rate of ≈1.2 mm/yr suggested by this method contrasts strongly with rates of ≈20 mm/yr that we estimated by correlation of alluvial deposition with warm humid periods associated with the last glacial termination estimated to have occurred about 12 ka in western Tibet. The 10 Be-based slip rate indicates that strong earthquakes can occur along faults with low slip rates and demonstrates the contribution of cosmic-ray–exposure dating in Quaternary tectonic analyses.
TL;DR: Data suggest that the rapidity of flavonoid formation plays an important role in the resistance of V. rotundifolia to P. viticola, and the formation of resveratrol, flavonoids and lignin in the intermediate resistant species probably restricts the development of this pathogen.
Journal Article•
TL;DR: In this paper, the acoustic properties of cylindrical silica aerogels in both ultrasonic and audible range are presented. But neither the classical theory of propagation in a homogeneous material nor the Biot theory for porous materials can explain the results.
Abstract: Acoustic properties of cylindrical silica aerogels in both ultrasonic and audible range are presented. Velocity measurements for low ultrasonic frequencies show that the low-density aerogels can exhibit unexpected attenuation for well-defined frequency bands. Measurements of the acoustical impedance of samples in the audible range show that the results depend dramatically on the geometry and/or the boundary conditions imposed to the samples. The ‘attenuation’ bands in which the samples present an unexpected high attenuation are related to the aerogel density. These particular results are discussed in two ways; first for application purposes and second in terms of a possible theoretical explanation. Neither the classical theory of propagation in a homogeneous material nor the Biot theory for porous materials can explain the results.
TL;DR: Results demonstrate that the implantation of a microdialysis probe in the ventral funiculus, close to a potential target of monoaminergic projections, is a suitable technique for the collection of neuromediators released during spontaneous running.
TL;DR: In this paper, it was shown that the relative loss of variability estimated by the number of alleles is smaller in inbreeders than in outbreede species, assuming populations with the same number of individuals.
Abstract: A loss of neutral genetic polymorphism is theoretically expected for many reasons in inbreeding organisms when compared to outbreeders. The first reason derives from the decrease of the effective population size, down to a halving, in purely selfing species. Other genetical reasons include hitchhiking and background selection. A loss can also be caused by ecological processes, that is by any kind of process provoking a genetic bottleneck. These theoretical expectations have been empirically confirmed in hermaphroditic plants for which selfing species exhibit both a lower gene diversity and number of alleles per population. Here I extend the analysis to hermaphroditic animals, mainly terrestrial and freshwater snails. The decrease of variability in selfers is far greater than what is expected under the halving of the effective size of populations only. Hitchhiking and background selection certainly cannot be rejected as causes of this extra loss. Bottlenecks can clearly be invoked in tropical freshwater snails. However a crude theoretical analysis using Ewens's sampling formulae shows that the relative loss of variability estimated by the number of alleles is smaller in inbreeders than in outbreeders assuming populations with the same number of individuals. This suggests that bottlenecks contribute less to the loss in selfers than in outcrossers. Variability lost within selfing populations of hermaphroditic animals is also lost at the level of a group of populations (metapopulation). This is theoretically not always expected. Indeed, I calculate the ratio of the effective size of a selfing metapopulation to be greater than that of an outcrossing one using previously derived equations. The large variation of this ratio which depends on both migration and effective size of subpopulations prevents prediction of the relative amount of genetic variability stored by selfing and outcrossing metapopulations.
University of California, Santa Cruz1, University of Texas at Austin2, Lamont–Doherty Earth Observatory3, University of Tsukuba4, Indiana Geological Survey5, University of Hawaii6, University of Montpellier7, University of Kiel8, École Normale Supérieure9, University of Tokyo10, Ocean Drilling Program11, Woods Hole Oceanographic Institution12, University of Minnesota13, University of California, San Diego14, University of Technology, Sydney15, Aberystwyth University16, University of Birmingham17, University of Missouri18, Florida State University19
TL;DR: In this paper, the authors measured density in situ, through the accretionary prism and decollement zone of the northern Barbados ridge, and derived void ratio (derived from density) to effective stress and predict a fluid pressure profile, assuming that the upper 100 m of the prism is at a hydrostatic pressure.
Abstract: Logs collected while drilling measured density in situ, through
the accretionary prism and decollement zone of the northern Barbados
Ridge. Consolidation tests relate void ratio (derived from
density) to effective stress and predict a fluid pressure profile, assuming
that the upper 100 m of the prism is at a hydrostatic pressure
gradient. The calculated fluid pressure curve rises to >90% of
lithostatic below thrusts in the prism, presumably due to the increase
in overburden and lateral tectonic loading. Thin (0.5–2.0 m)
intervals of anomalously low density and resistivity in the logs
through the basal decollement zone suggest dilation and perhaps
hydrofracturing. A peak in hydraulic head in the upper half of the
decollement zone requires lateral influx of fluid, a conclusion consistent
with previous geochemical studies. Although the calculated
fluid-pressure profile is model dependent, its inherent character
ties to major structural features.
TL;DR: The capacity of a retro-inverso form of a 16-residue peptide from the Antennapedia homeodomain to be taken up by cultured neurones was tested, and like its homologue made of L-amino acids, it was rapidly internalised and distributed throughout the cytoplasm and even the cell nucleus.
TL;DR: In this review, recent results obtained in the shrimp Penaeus japonicus are presented and discussed with reference to the Crustacea and other arthropods.
TL;DR: In this article, the size of the D = 4 to 9 condensates was estimated by fitting a fitting procedure without invoking stability criteria, using a τ-like inclusive process and QCD spectral sum rules.
Journal Article•
TL;DR: An up-regulation of NMDA and metabotropic glutamate receptors in the primary auditory neurons occurred during this process of recovery and probably accounts for restoring hearing after temporary losses due to excitotoxic-related pathologies.
Abstract: Cochlear ischemia and acoustic trauma result in an immediate hearing loss accompanied by the complete disruption of the terminal dendrites of primary auditory neurons postsynaptic to the sensory inner hair cells (IHCs) This synaptic uncoupling, due to an acute glutamate (IHC neurotransmitter) excitotoxicity process, can be mimicked by glutamate agonists Thus, we have followed over a 5-day period the responses of guinea-pig cochleas to a local application of 200 microM AMPA This application immediately results in a destruction of all postsynaptic endings of the auditory nerve, resulting in a total loss of cochlear potentials Twenty-four hours after this excitotoxic injury, the inner hair cells were contacted by repaired postsynaptic dendrites and the cochlear potential had partially recovered This process of neo-synaptogenesis was completed and the potentials were fully restored at 5 days post exposure As shown by in situ hybridization, an up-regulation of NMDA and metabotropic glutamate receptors in the primary auditory neurons occurred during this process of recovery This process of neo-synaptogenesis and functional recovery probably accounts for restoring hearing after temporary losses due to excitotoxic-related pathologies
TL;DR: In this article, the Raman and IR spectra of poly(L-lactic acid) in amorphous and semicrystalline states were recorded from 3600 to 100 cm−1.
Abstract: The Raman and IR spectra of poly(L-lactic acid) in the amorphous and semicrystalline states were recorded from 3600 to 100 cm−1. Complete vibrational assignments are proposed. In the Raman spectra, the splittings of the vC=O stretching and the δCCO bend are characteristic of the crystalline phase and the presence of the two lines at 923 and 520 cm−1 indicates a 103 helical conformation.