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International audience; An elementary kinetic model was developed to predict the electrochemical response of porous LSCF and LSCF-CGO electrodes. The model was validated thanks to experiments performed on symmetrical cells using a three-electrode setup. After the model calibration on polarization curves, it has been shown that the model is able to simulate accurately the experimental impedance diagram at OCP and under polarization without additional fitting. Moreover, the evolution of the electrode polarization resistance with the oxygen partial pressure is well reproduced by the model. The electrodes reaction mechanism was thoroughly analyzed and it has been shown that the transition from the bulk path to the surface path depends on the temperature, the polarization and the oxygen partial pressure. The rate-determining steps for the LSCF electrode have been identified at OCP as function of the oxygen partial pressure. Finally, a sensitivity analysis has been performed to study the impact of LSCF demixing on the electrode performances. For a given decomposition, it has been highlighted that the surface passivation would be more impacting than the decrease of the ionic conductivity. Moreover, the impact of the LSCF decomposition would be more detrimental for the electrode performances evaluated in electrolysis mode.

Background and aim: Obstructive sleep apnea (OSA) is an independent risk factor for dyslipidemia. The current study examined the effects of positive airway pressure (PAP) treatment on lipid status in the European Sleep Apnea Database (ESADA). Methods: The prospective cohort study enrolled 1564 OSA subjects (74% male, mean age 54 ± 11y, body mass index (BMI) 32.7 ± 6.6 kg/m2 and apnea-hypopnea index (AHI) 40.3 ± 24.4 n/h) undergoing PAP therapy for at least three months (mean 377.6 ± 419.5 days). Baseline and follow-up total cholesterol (TC) from nine centers were analyzed. Repeated measures and logistic regression tests (adjusted for age, sex, weight changes, lipid lowering medication, PAP compliance, and treatment duration) were used to compare changes in TC concentration. Incident risk for a coronary heart disease event (CHD) was used to compute a Framingham CHD risk score (estimated from age, BMI, blood pressure, and TC). Results: Adjusted means of TC decreased from 194.2 mg/dl to 189.3 mg/dl during follow-up (p = 0.019). A clinically significant (10%) reduction of TC at PAP follow-up was observed in 422 patients (27%). Duration of PAP therapy was identified as independent predictor for TC reduction, which implies an approximately 10% risk reduction for incident CHD events (from 26.7% to 24.1% in men and from 11.2% to 10.1% in women, p < 0.001 respectively). Conclusion: This observational study demonstrates a reduction of TC after long-term PAP treatment. The close association between TC concentration and cardiovascular (CV) mortality suggests that identification and treatment of OSA may have a beneficial effect on overall CV risk due to this mechanism. This possibility needs to be evaluated in prospective randomized studies. © 2020 Elsevier B.V., ResMed Foundation European Respiratory Society, ERS European Respiratory Society, ERS European Respiratory Society, ERS, The ESADA network has received support from the European Union COST action B26 and the European Respiratory Society (ERS) funded Clinical Research Collaboration (CRC). Unrestricted seeding grants from the ResMed Foundation and the Philips Respironics Foundation for establishment of the database in 2007 and 2011 are gratefully acknowledged. The ESADA network has a scientific collaboration with Bayer AG., Nonfinancial support was provided by the European Sleep Research Society (ESRS) and the European Respiratory Society (ERS) in terms of logistics for communication, meetings and data presentations for the ESADA collaborators., Dr. Verbraecken reports grants and personal fees from ResMed, Bioprojet, Jazz Pharmaceutics; personal fees from Philips, Sanofi, Agfa-Gevaert, grants from AirLiquide; personal fees from Springer, Westfalen Medical, SomnoMed, Vivisol, Total Care, Medidis, Fisher & Paykel, Wave Medical, OSG, Mediq Tefa, NightBalance, Heinen & Löwenstein, AstraZen, Accuramed, Bekaert Deslee Academy and UCB Pharma, outside the submitted work. Dr. Hedner reports grants from ResMed, Philips Respironics, and the European Respiratory Society all related to maintenance of database on behalf of the ESADA group during the conduct of the study. Dr. Grote reports grants from Bayer, Resmed, Respironics/Philips, and from the European Respiratory Society during the conduct of the study; non-financial support and other from Itamar Medical, Resmed, Philips, and Astra Zeneca, outside the submitted work. In addition, Dr. Grote has a patent on sleep apnea therapy licensed. The remaining co-authors have no conflict of interest to declare.

This work aims at investigating through a modeling approach the difference in thermal and electrochemical responses between high temperature H 2 O electrolysis and H 2 O+CO 2 co-electrolysis in solid oxide cells. The study has been conducted by considering a typical planar stack configuration with cathode supported cells. The influence of the local temperature on the polarization curve is discussed. Operating maps are simulated for both electrolysis modes depending on cell voltage and inlet gas flow rate, covering a complete range of gas conversion rates. The optimum domains of operating conditions combining high performances and reasonable temperature elevations are identified. In overall, higher performances are found in steam electrolysis. Indeed, the co-electrolysis process is found to be strongly limited by mass transport through the thick cathode. However, co-electrolysis exhibits an easier thermal management. Finally, the composition of the syngas produced by co-electrolysis is found to be highly flexible through adjustments of the operating parameters.

Introduction Sleep Apnea Syndrome (SAS) is largely underdiagnosed due to the cost and availability of Polysomnography (PSG). We aimed at evaluating the diagnosis of SAS with the WITHINGS Sleep Apnea Detector (SAD), a non-intrusive pressure and sound sensor placed under the mattress. Methods 118 patients (67 F, 49 years, BMI 33kg/m²) suspected of SAS had an in-laboratory PSG together with Sleep Apnea Detector. From the pressure signal, Sleep Apnea Detector derives respiratory and cardiac signals and movements. From the microphone, snoring and snorting are detected. These features are used to detect sleep periods with a Random Forest classifier and apnea and hypopnea events with a Convolutional Neural Network. The Total Sleep Time (TST) and Apnea Hypopnea Index (AHI) deduced (TSTsad, AHIsad) are compared with the PSG results scored according to AASM rules (TSTpsg, AHIpsg). AHI and TST were compared using bias and Mean Absolute Error (MAE). Sensitivity, specificity, likelihood ratios (LR) and AUROC were calculated for AHI thresholds of 15 and 30/hr. Results The average (SD) TSTpsg was 367 (61) minutes. Sleep Apnea Detector overestimated TST by 25 minutes, 7.0% of the average duration in the sample. The precision is acceptable, with a MAE=53 minutes. Average AHIpsg was 32.5 (30.1) and AHIsad 32.8 (29.9). The bias was 0.3 (95% CI [-2.7, 3.3]), MAE=10.3. The sensitivity (Se15) and specificity (Sp15) and their 95% confidence intervals were Se15=88.0% [79.0, 94.1] and Sp15=88.6% [73.3, 96.8]. Positive and negative LR were respectively LR+15=7.70 and LR-15=0.136. AUROC15=0.926. At the 30 threshold, Se30=86.0% [73.3, 94.2] and Sp30=91.2% [81.8, 96.7]. Positive and negative LR were LR+30=9.75 and LR-30=0.153. AUROC30=0.954. Conclusion Sleep Apnea Detector has excellent sensitivity and specificity, low bias and good precision. Thus it can be used as an unattended SAS screening device in patients likely to suffer from SAS. Support WITHINGS

This work highlights an experimental and modeling approach devoted to a better understanding of H2O and CO2 co-electrolysis mechanisms at 800 °C. A standard Cathode Supported Cell (CSC) was used in this study. Through numerical adjustments on experimental polarization curves, the cathode microstructural parameters and exchange current densities for H2O and CO2 reductions were determined and subsequently implemented in an in-house co-electrolysis model. Additionally, micro gas chromatography (μGC) analyses were performed in co-electrolysis operating mode for different cell polarizations (from i = 0 to i = −1.75 A cm−2). μGC analyses at Open Circuit Voltage (OCV) were used to validate the kinetic constants of the Water Gas Shift (WGS) reaction implemented in the model. Predictions of both co-electrolysis polarization curves and outlet gas compositions were then compared to the experimental measurements. The good agreement between simulated and experimental data proves the relevance of the macroscopic representation of electrochemical processes through a “surface ratio” that takes into account the H2O and CO2 electrolyzes competition. A sensitivity analysis was performed to ensure a better understanding of co-electrolysis mechanisms and further investigate the influence of the reverse WGS reaction over CO production.

In this work, a comprehensive, predictive and quantitative model of a whole gas analyzer is provided in order to facilitate the design of such high performance devices. All the pre-analytical (gas separation) and analytical (detection and readout) stages have been modeled and experimentally calibrated. Heterogeneous simulations have been used to quantify the impact of the whole architecture on the output characteristic of the gas analyzer. Finally, the model of the NEMS sensor and the chromatography micro-column assembly has been experimentally validated with TEOX (toluene, ethylbenzene, octane, and xylene) gases.

An in-house micro model has been built to describe the electrochemical mechanisms governing both H2 and O2 electrodes operating in SOEC mode. A special attention has been paid to take into account the microstructure properties of the ionic, electronic and gas phases as well as the processes occurring therein. A commercial LSM–YSZ symmetrical cell has been tested at 700, 750 and 850 °C in air. Simulations have been carried out to interpret the experimental data. It is suggested that the kinetic of O2 formation is controlled by a single charge transfer. A sensitivity analysis has been performed using the micro model to quantify the role of the microstructure in the electrode behaviour. Transport of oxygen ions in the functional layer has a strong impact on the cell response since it governs the delocalization of the electrochemical reactions. The density of TPB length is also a key parameter controlling the electrode efficiency. Evolutions of the microstructural parameters in operation have been associated to the degradation of the electrochemical performances. The decrease in TPB length due to Ni agglomeration has a moderate impact whereas the decrease in ionic conductivities of 8YSZ or LSFC could explain a large amount of the cell degradation.

Thalamic ventrobasal (VB) relay neurones express multiple GABA(A) receptor subtypes mediating phasic and tonic inhibition. During postnatal development, marked changes in subunit expression occur, presumably reflecting changes in functional properties of neuronal networks. The aims of this study were to characterize the properties of synaptic and extrasynaptic GABA(A) receptors of developing VB neurones and investigate the role of the alpha(1) subunit during maturation of GABA-ergic transmission, using electrophysiology and immunohistochemistry in wild type (WT) and alpha(1)(0/0) mice and mice engineered to express diazepam-insensitive receptors (alpha(1H101R), alpha(2H101R)). In immature brain, rapid (P8/9-P10/11) developmental change to mIPSC kinetics and increased expression of extrasynaptic receptors (P8-27) formed by the alpha(4) and delta subunit occurred independently of the alpha(1) subunit. Subsequently (> or = P15), synaptic alpha(2) subunit/gephyrin clusters of WT VB neurones were replaced by those containing the alpha(1) subunit. Surprisingly, in alpha(1)(0/0) VB neurones the frequency of mIPSCs decreased between P12 and P27, because the alpha(2) subunit also disappeared from these cells. The loss of synaptic GABA(A) receptors led to a delayed disruption of gephyrin clusters. Despite these alterations, GABA-ergic terminals were preserved, perhaps maintaining tonic inhibition. These results demonstrate that maturation of synaptic and extrasynaptic GABA(A) receptors in VB follows a developmental programme independent of the alpha(1) subunit. Changes to synaptic GABA(A) receptor function and the increased expression of extrasynaptic GABA(A) receptors represent two distinct mechanisms for fine-tuning GABA-ergic control of thalamic relay neurone activity during development.

Gephyrin is a multifunctional protein contributing to molybdenum cofactor (Moco) synthesis and postsynaptic clustering of glycine and GABAA receptors. It contains three major functional domains (G-C-E) and forms cytosolic aggregates and postsynaptic clusters by unknown mechanisms. Here, structural determinants of gephyrin aggregation and clustering were investigated by neuronal transfection of EGFP-tagged deletion and mutant gephyrin constructs. EGFP-gephyrin formed postsynaptic clusters containing endogenous gephyrin and GABAA-receptors. Isolated GC- or E-domains failed to aggregate and exerted dominant-negative effects on endogenous gephyrin clustering. A construct interfering with intermolecular E-domain dimerization readily auto-aggregated but showed impaired postsynaptic clustering. Finally, two mutant constructs with substitution of vertebrate-specific E-domain sequences with homologue bacterial MoeA sequences uncovered a region crucial for gephyrin clustering. One construct failed to aggregate, but retained Moco biosynthesis capacity, demonstrating the independence of gephyrin enzymatic activity and aggregation. Reinserting two vertebrate-specific residues restored gephyrin aggregation and increased formation of postsynaptic clusters containing GABAA receptors at the expense of PSD-95 clusters – a marker of glutamatergic synapses. These results underscore the key role of specific E-domain regions distinct from the known dimerization interface for controlling gephyrin aggregation and postsynaptic clustering and suggest that formation of gephyrin clusters influences the homeostatic balance between inhibitory and excitatory synapses.

The time-frequency characteristics of muscular sounds (phonomyogram) produced by the contraction of the human diaphragm under various contractile states is evaluated with the cone-kernel distribution. The results show that the instantaneous frequency of the phonomyogram of the diaphragm has a high cross-correlation (an average of 0.91 +/- 0.06) with the transdiaphragmatic pressure, with a delay varying between 25 and 35 ms. The instantaneous frequency response of the phonomyogram of the diaphragm shows a behaviour similar to that of the frog muscle; it rapidly rises and then fades out. However, the maximum of the instantaneous frequency of the phonomyogram of the diaphragm is not proportional to the maximum of the transdiaphragmatic pressure. This analysis also demonstrates the usefulness of the cone-kernel distribution for studying frequency-modulated signals like the muscular sound signals.

BACKGROUND: A diaphragmatic phonomyogram (PMG) evoked by maximal phrenic nerve stimulation at end expiratory lung volume (FRC) has been previously described as a good index of changes in diaphragmatic contractility with fatigue. A study was undertaken to assess whether this conclusion could be extended to different lung volumes. METHODS: Diaphragmatic compound motor action potentials (CMAPs) were recorded on each side of the chest by the means of surface electrodes placed over the eight intercostal spaces in five healthy subjects. Diaphragmatic PMGs from both sides were recorded with condenser microphones fixed to the skin close to the CMAP recording electrodes. Oesophageal and gastric balloon tipped catheters were employed to measure transdiaphragmatic pressure twitches (TwPDI) which served as the standard measure of changes in diaphragmatic contractility. PMG and TwPDI responses were compared at different lung volumes over inspiratory capacity both before and after fatiguing inspiratory resistive loading. RESULTS: No consistent relationship was found in different subjects or on different days in the same subject between PMG and lung volume or between PMG and TwPDI. However, the PMG:CMAP ratio from both sides at any given lung volume decreased after fatigue in roughly the same proportion as the TwPDI. CONCLUSIONS: These results show that, although PMG can detect changes in diaphragmatic contractility caused by fatigue in normal subjects, lung volume changes need to be controlled and each subject should serve as his or her own control.

The ref(2)P gene of Drosophila melanogaster interferes with sigma rhabdovirus multiplication. This gene is highly variable, and the different alleles are considered permissive or restrictive according to their effects on virus replication. In all cases, the mechanisms involve intracellular interactions between the sigma virus and Ref(2)P proteins. We showed that the N-terminal domain of the Ref(2)P protein was required for its activity in vivo. The protein was inactive in the null p(od)2 mutant when its first 82 amino acids were deleted. The p delta n gene was constructed so that the first 91 amino acids coded for by the restrictive alleles could be expressed in vivo. It was active in a transformed line. This sequence was sufficient to impart a restrictive phenotype to an adult D. melanogaster fly after it was injected with the virus. However, the truncated protein expressed by p delta n did not have an effect on the hereditary transmission of the sigma virus to the offspring of the infected flies, even though it contained the restriction site. The native Ref(2)P protein has been previously shown to have conformation-dependent epitopes common with some of those of the viral N protein. We demonstrated the following. (i) These epitopes were found in a domain of the Ref(2)P protein distinct from the site involved in restriction. (ii) They were modified in the N protein of the haP7 sigma virus mutant selected as being adapted to the restrictive alleles of the ref(2)P gene; only one mutation in the N gene, leading to an amino acid substitution, distinguished the haP7 mutant from the original virus. (iii) The virus strains partially or totally adapted to the effects of the full restrictive protein expressed by pp were always found to multiply to a lesser extent in the presence of the protein expressed by p delta n. These data suggest that two distinct domains of the Ref(2)P protein are involved in the control of sigma virus multiplication.

ISBN: 978-1-4577-0506-9; International audience; This work demonstrates for the first time a VLSI-compatible nano/microfabricated, high-performance, portable multi-gas analyzer associating gas chromatography and NEMS resonators.

We report on silicon oxide deposited by direct photolysis at 185 nm of an N2OSiH4 mixture. Films are deposited at 250°C under a 665 Pa pressure on indium phosphide (InP). To determine the best insulator in terms of physico-chemical and electrical properties, the ratio R = SiH 4 N 2 O has been varied. A quasi-stoichiometric silicon oxide is obtained for R = 2% (O/Si = 1·87 instead of 2), the hydrogen and the nitrogen contents being, respectively, ≈15% and ≈5%. Electrical characterization has been done on Metal Insulator Semiconductor (MIS) diodes. After dipping InP in an (NH4)2SX solution, and after an appropriate annealing procedure, the density of states Nss is of the order of 1011 eV−1 cm−2. A quite good resistivity of 1015 ohm.cm is observed. Simple depletion mode Field Effect Transistors (MISFETs) are then made, and present a transconductance gm of 63 mS/mm and an Fmax of 20 GHz.

High quality silicon nitride films are deposited at low temperature on InP substrates by direct photolysis at 185 nm of a NH3-SiH4 gas mixture. The composition of the films is measured by nuclear analysis. The thickness and refractive index are obtained by ellipsometry at 632.8 nm. As-deposited and post annealed samples are electrically characterized: quasi-static I(V) at 5×10−4 Hz and C(V) characteristics at 1 MHz are performed on InP MIS diodes structures in order to optimize bulk and interface properties. At 250° C and 4 Torr, it is found that the highest critical field (measured for a leakage current density of 10−9 A/cm2) is obtained for the injected ratio [SiH4]/[NH3]=2%. For these conditions, the film is stoichiometric, the critical field is 4 MV/cm and the resistivity is 6×1015 Ω cm. The interface state density (Nss) on InP is deduced from Terman analysis. The annealing conditions and the surface cleaning of InP have been optimized in order to reduce the Nss which is, for our best conditions, as low as 2×1011 eV−1 cm−2.

Thalamic ventrobasal (VB) relay neurones express multiple GABA(A) receptor subtypes mediating phasic and tonic inhibition. During postnatal development, marked changes in subunit expression occur, presumably reflecting changes in functional properties of neuronal networks. The aims of this study were to characterize the properties of synaptic and extrasynaptic GABA(A) receptors of developing VB neurones and investigate the role of the alpha(1) subunit during maturation of GABA-ergic transmission, using electrophysiology and immunohistochemistry in wild type (WT) and alpha(1)(0/0) mice and mice engineered to express diazepam-insensitive receptors (alpha(1H101R), alpha(2H101R)). In immature brain, rapid (P8/9-P10/11) developmental change to mIPSC kinetics and increased expression of extrasynaptic receptors (P8-27) formed by the alpha(4) and delta subunit occurred independently of the alpha(1) subunit. Subsequently (or = P15), synaptic alpha(2) subunit/gephyrin clusters of WT VB neurones were replaced by those containing the alpha(1) subunit. Surprisingly, in alpha(1)(0/0) VB neurones the frequency of mIPSCs decreased between P12 and P27, because the alpha(2) subunit also disappeared from these cells. The loss of synaptic GABA(A) receptors led to a delayed disruption of gephyrin clusters. Despite these alterations, GABA-ergic terminals were preserved, perhaps maintaining tonic inhibition. These results demonstrate that maturation of synaptic and extrasynaptic GABA(A) receptors in VB follows a developmental programme independent of the alpha(1) subunit. Changes to synaptic GABA(A) receptor function and the increased expression of extrasynaptic GABA(A) receptors represent two distinct mechanisms for fine-tuning GABA-ergic control of thalamic relay neurone activity during development.

Ref(2)P has been described as one of the Drosophila proteins that interacts with the sigma virus cycle. We generated alleles to identify critical residues involved in the restrictive (inhibiting viral multiplication) or permissive (allowing viral multiplication) character of Ref(2)P. We demonstrate that permissive alleles increase the ability of the sigma virus to infect Drosophila when compared to null alleles and we confirm that restrictive alleles decrease this capacity. Moreover, we have created alleles unfunctional in viral cycling while functional for Ref(2)P fly functions. This type of allele had never been observed before and shows that fly- and virus-related activities of Ref(2)P are separable. The viral status of Ref(2)P variants is determined by the amino-terminal PB1 domain polymorphism. In addition, an isolated PB1 domain mimics virus-related functions even if it is similar to a loss of function toward fly-related activities. The evolutionary tree of the Ref(2)P PB1 domain that we could build on the basis of the natural allele sequences is in agreement with an evolution of PB1 domain due to successive transient selection waves.

Asthma affecting elite athletes has been studied mainly in subjects practicing winter sports. The aim of our study was to test the pulmonary function in order to evaluate bronchial hyper-responsiveness prevalence in a team of 25 male professional cyclists (27.9+/-3.9 years old with a VO(2max) equal to 69.9+/-6.6 mL.min(-1) x kg(-1)).Using a questionnaire that queried the presence or absence of asthma history or common symptoms of exercise induced bronchospasm, 72% of the subjects had upper airway or bronchial symptoms. Using a pneumotachograph, we recorded a forced flow-volume curve at rest, after a maximal exercise test with ambient air, and after beta2-agonist inhalation, then during a methacholine challenge.In our study, 52% of the subjects showed clinical symptoms associated with bronchial responsiveness during methacholine test, a proportion which is much higher than the average population (3-20%). However, ERS-ATS pulmonary function testing criteria at rest (reduced FEV1, FEV1/FVC, FEF25-75%) were not fulfilled by any of them. In the asthmatic group, O2max was significantly higher (70.5+/-6 vs 68.6+/-8.2 mL.min-1.kg-1, P0.05). This remained true for submaximal loads suggesting that ventilation energy cost related to bronchial hyper-responsiveness was also higher.We have reported in this study that professional cyclists have a far higher prevalence of bronchial hyper-responsiveness than the average population, which can be regarded as a real health issue.

The aggression of erythrocytes by an oxidative stress induces hemolysis. This paper aims to valid a model of erythrocytes in terms of composition of the phosphate buffer solution and of concentration of a well-known oxidant, AAPH. Three compositions of phosphate buffer solution are mixed with three concentrations of oxidant. The influence of these two parameters on hemolysis is independently studied by a variance analysis and a Kruskal-Wallis test when ANOVA is not available. The hemolysis rate increases with time at fixed oxidant concentration, but is not influenced by the composition of the buffer solution. The highest hemolysis rate, 90%, was only measured within 2 h with the highest oxidant concentration. If we retain this concentration of oxidant, the lower concentration of the buffer can by eliminated by a significant less hemolysis and the highest concentration of the buffer can by chosen in regard of the better precision for a similar hemolysis compared to the mean buffer. We hope to study the effect of anti-oxidant agent with such a model of erythrocytes.

The preparation of high quality silicon nitride films by direct photolysis of NH/sub 3/-SiH/sub 4/ at low temperature and their deposition onto InP substrates are discussed. The atomic composition of the films is determined by nuclear analysis. In order to optimise bulk and interface properties quasi-static I(V) and C(V) characteristics measurements were performed on MIS diodes at 1 MHz. At 250 degrees C, a critical field of 4 MV/cm and a resistivity of 6*10/sup 15/ Omega -cm are observed. For annealed samples. a density of states of 4*10/sup 11/ cm/sup -2/ eV/sup -1/ is determined by Terman analysis. The fabrication of a preliminary InP depletion mode MISFET without a recess and N/sup +/ contact layer is described. >

SiNH and SiOH have been deposited on InP by ultraviolet chemical vapor deposition (UVCVD), distributed electronic cyclotronic resonance (DECR) plasma-enhanced chemical vapor deposition (PECVD), and pulsed 13.56 MHz PECVD at 250 degrees C. A comparison between deposition techniques is presented in terms of interface composition (XPS), defect creation in InP (ETOCAPS), and secondary ion mass spectrometry (SIMS) profiles on metal-insulator-silicon diodes. >

The ref(2)P gene is involved in the control of sigma rhabdovirus multiplication in Drosophila melanogaster. ref(2)P activity is also necessary for male fertility. However, in one-third of laboratory strains tested, males that lacked ref(2)P activity were fertile. In all such strains studied, the male sterility phenotype was abolished due to the presence of a particular allele at the Su(P) locus, at 73B1–2. These spontaneous suppressor alleles were dominant. We were able to induce dominant suppressor alleles at the Su(P) locus by X-ray mutagenesis and hybrid dysgenesis, suggesting that null alleles of Su(P) confer the dominant suppressor phenotype. The Su(P) gene was cloned by P element tagging. The P element-tagged alleles identified a Su(P) transcript as a 1.4-kb mRNA produced in the soma of both males and females, which is also abundant in ovaries.

Diaphragmatic phonomyogram (PMG) evoked by maximal bilateral phrenic nerve stimulation has previously been described as a good index of contractility of fresh and fatigued diaphragm. In the present study we hypothesized that diaphragmatic contractility changes could be even more simply evaluated by recording the relationship between the PMG and the compound motor action potential (CMAP) amplitudes during graded submaximal unilateral phrenic nerve stimulation at various intensities. Relationships between CMAPs and PMGs from left and right hemidiaphragms were recorded by means of surface electrodes and miniature microphones placed over the lower rib cage (eighth intercostal space) in five healthy subjects before and after a diaphragmatic fatigue task. These relationships in each subject were linear. The slope of these relationships decreased by 61.1 +/- 20.7% and by 70.4 +/- 14.6% on the right and left side respectively, but the intercepts did not change significantly. By comparison, transdiaphragmatic twitch pressure during maximal bilateral stimulation (PdiT) declined by 49.4 +/- 15%. We conclude that PMG during submaximal unilateral phrenic nerve stimulation is a reliable index of diaphragm contractility changes caused by fatigue. Using this method we have shown that all diaphragmatic motor units can be affected by fatigue.

The ref(2)P gene of Drosophila melanogaster was identified by the discovery of two alleles, Po and Pp, respectively, permissive and restrictive for sigma rhabdovirus multiplication. A surprising variability of this gene was first noticed by the observation of size differences between the transcripts of permissive and restrictive alleles. In this paper, another restrictive allele, Pn, clearly distinct from Pp, is described: it exhibits a weaker antiviral effect than Pp and differs from Pp by its molecular structure. Five types of alleles were distinguished on the basis of their molecular structure, as revealed by S1 nuclease analysis of 17 D. melanogaster strains; three alleles were permissive and two restrictive. Comparison of the sequences of four haplotypes revealed numerous point mutations, two deletions (21 and 24 bp) and a complex event involving a 3-bp deletion, all affected the coding region. The unusual variability of the ref(2)P locus was confirmed by the high ratio of amino acid replacements to synonymous mutations (7:1), as compared to that of other genes, such as the Adh (2:42). Nevertheless, nucleotide sequence comparison with the Drosophila erecta ref(2)P gene shows that selective pressures are exerted to maintain the existence of a functional protein. The effects of this high variability on the ref(2)P protein are discussed in relation to its specific antiviral properties and to its function in D. melanogaster, where it is required for male fertility.

Subjects with chronic alcoholism are associated with a higher prevalence of bone fractures, compared with age-matched controls. However, the pathogenesis of alcoholic osteopathy remains poorly understood. In this study, the bone cells activities and the bone matrix were studied using different techniques such as bone morphometry, scanning electron microscopy and computer reconstruction. Male patients (N = 20), aged 59.1 +/- 10.1 years, presenting a chronic decompensated alcoholic cirrhosis, were admitted into this study. A histomorphometric analysis of a transiliac bone biopsy was done after a double tetracycline labeling of the bone. A scanning electron microscopy (SEM) study was performed on eight out of the 20 patients on an additional biopsy. The bone mass was significantly decreased in cirrhotic patients. A marked defect in the osteoblastic function was observed with reduced osteoid parameters, lower mean wall thickness, and slower bone formation rate leading to a thinning of bone trabeculae. Conversely, trabecular resorption surfaces were markedly increased. SEM examination of bone biopsies was also consistent with delayed and impaired osteoblastic activity leading to extended and scalloped resorption surfaces covered by unusually thin layers of calcified collagen fibers. The reduced osteoblastic activity associated with normal osteoclastic function appears to play a major role in the pathogenesis of alcoholic osteoporosis leading to decreased bone mass with thinner trabeculae.

We present in this article a simple and economic gas line designed for low vapor pressure metalorganic sources introduced into a chemical beam epitaxy chamber without carrier gas. This gas line was tested with triethylgallium and trimethylindium for the growth of GaAs and InP layers. The high conductance of the line allowed minimizing the heating of the source and reaching growth rate as high as 12 μm/h for GaAs. The lower InP growth rate was attributed to the higher viscosity of trimethylindium compared to triethylgallium.

Fresh liver slices were shock-frozen in liquid nitrogen at −196°C, then powdered in a kitchen-mixer at the boiling temperature of the liquid nitrogen. The powdered liver was given to the larvae of a cyprinid hybrid fish (bighead carp × silver carp) in open-flow containers at 26–27°C. During the 3 weeks of feeding, growth and survival of the larvae were comparable with those of sibs fed living zooplankton.

The ref(2)P gene of Drosophila melanogaster has two common alleles, ref(2)Po which permits the infection of flies by the rhabdovirus sigma (sigma), and ref(2)Pp which is restrictive for sigma infection. This gene has been cloned by P element tagging and shown to code for two RNAs in adult flies. These RNAs are expressed in both males and females, but only the larger is expressed in ovaries. Both transcripts are shorter, by about 50 nucleotides, in flies carrying the ref(2)Pp allele than in those carrying ref(2)Po. The dominance relationships of these two alleles, and the fact that ref(2)Pnull alleles are permissive to sigma infection, suggest that the ref(2)Po product is antimorphic to that of the ref(2)Pp allele.

Die partielle Entwasserung von Hydrargillit-Kristallen sowie von mikrokristallinen Bohmit-Gelen fuhrt zu festen Substanzen mit absorbierenden Eigenschaften. Die thermische Stabilitat des kristallinen Bohmits ist zu gros, um entsprechende thermische Spaltungsprodukte zu geben. Die durch nahezu vollstandige Entwasserung entstehenden festen Substanzen haben je nach den Ausgangshydraten verschiedene kristalline Strukturen. Die katalytische Aktivitat wird durch diese Unterschiede beeinflust. Thermogravimetrisch, rontgenographisch sowie durch Untersuchungen der spezifischen Oberflache und der Porositat konnen die fur Adsorption und Katalyse aktiven Phasen erfast und ihr Bildungsmechanismus beschrieben werden.

Sigma virus has been concentrated by means of polyethylene-glycol and diafiltration; the latter method is more efficient in preserving infectivity. When purified on sucrose gradient, sigma banded in a sharp peak without any polydispersion. We are now able to label sigma genome with 3H-uridine in Drosophila cell cultures.

Vesicular stomatitis virus (VSV) establishes a non-cytopathic persistent infection in Drosophila melanogaster cells. The synthesis of the viral glycoprotein G was specifically inhibited during a post-transcriptional step, whereas the synthesis and turnover of its mRNA were not modified compared with the other viral mRNAs. Another viral glycoprotein, migrating slightly faster than G protein on an SDS-polyacrylamide gel, was detected in infected Drosophila cells. This protein showed most of the characteristics of the intracellular Gs protein found in infected vertebrate cells. The amounts of G protein integrated into mature virions and of soluble Gs protein secreted into the culture medium were reduced greatly during VSV infection in Drosophila cells.

Vesicular stomatitis virus RNA synthesis was investigated during the establishment of persistent infection in Drosophila melanogaster cells. The transcription rate declined as early as 5 h after infection and was strongly inhibited after 7 h, leading to a decrease in viral mRNA levels and in viral protein synthesis rates. Full-length plus-strand antigenomes and minus-strand genomes were detected after a 3-h lag time and accumulated until 15 h after infection. Short encapsidated plus-strand molecules were also generated corresponding to the 5' end of viral defective antigenomes. Assembly and release of virions were not restricted, but their infectivity was extremely reduced. In persistently infected cells, an equilibrium was reached where the level of intracellular genomes maintained was constant and maximal even after the rate of all viral syntheses had decreased. These results are discussed with regard to the establishment of persistent infection.

In cultured Drosophila melanogaster cells, vesicular stomatitis virus (VSV) establishes a persistent, noncytopathic infection. No inhibition of host macromolecular synthesis occurs. We studied the synthesis of VSV plus-strand leader RNA, which may be directly involved in vertebrate host synthesis shut-off. Leader RNA accumulated in Drosophila cell cytoplasm, but in low amounts, it was either free or associated to structures larger than the leader RNA-N protein complexes found in vertebrate cells. Only a few leader RNA copies migrated into the cell nucleus; no increase of this transport was observed at any time during the virus cycle. Viral RNAs complementary to the 3' end of the genome and ranging in size from the leader to several hundred nucleotides were found to accumulate in Drosophila cell cytoplasm. Their synthesis was inhibited in the presence of cycloheximide, which blocks all protein synthesis and VSV replication. Correlation between the absence of VSV cytopathogenicity in Drosophila cells and the lack of leader RNA transport into their nuclei is discussed, as well as the possible relationship between the restriction of viral synthesis and the frequent initiation of an abortive replication step.

Deux cent cinquante-six coqs des génotypes Na Na, Na na’ et na’ na’ ont été comparés pour leurs performances de croissance, leur consommation alimentaire et des caractéristiques morphologiques et physiologiques, soit à la température ambiante de 18 °C à partir de l’âge de 9 semaines, soit à 30 °C. Au total, la température de 30 °C, par comparaison à 18 °C, diminue la consommation alimentaire, le poids vif, le rythme respiratoire, l’hématocrite, et augmente la croissance des os en longueur, la température interne et superficielle, la surface de la crête et des barbillons. Parmi les effets associés au gène Na, certains apparaissent aux 2 températures : accroissement de consommation alimentaire, du rythme respiratoire, de l’hématocrite, légère diminution de la température interne et superficielle, réduction de la longueur des tarses, augmentation de la taille des barbillons. Le poids vif ne montre pas, au total, d’effet significatif lié au génotype au locus Na ; cependant, les données aux divers âges suggèrent que ce génotype l’affecte en sens contraire aux 2 températures. L’hétérozygote Na na+ est généralement intermédiaire entre les 2 homozygotes., Two hundred and fifty six cockerels of the genotypes Na Na, Na n+ a and n+ a n+ a were compared for their growth performance, feed consumption and morphological and physiological traits, either at 18 °C from the age of 9 weeks or at 30 °C. On the whole, the temperature of 30 °C, as compared to 18 °C, decreased feed intake, body weight, respiration rate, packed cell volume and increased length of long bones, internal and surface body temperature, comb and wattle area. Some effects associated with the Na gene appeared at both ambient temperatures : increase of feed consumption, of respiration rate and packed cell volume, slight decrease of internal and surface body temperature, reduction of shank length, increase of wattle size. Body weight on the whole did not show any significant genotype effect ; however, the data at various ages suggest that it is affected by the genotype at the Na locus in opposite directions at the 2 ambient temperatures. The Na na+ heterozygote is generally intermediate between the two homozygotes.