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Frequency-modulated continuous-wave lidar is evaluated for laser anemometry for helicopter, range finding and velocimetry at long range. Optimized signal processing is described as well as demonstration of range-finding/velocimetry from a few meters up to 10 km.

Throughout the last decades, development of low-temperat- ure detectors focused mainly on the design of high-sensitivity, single-pixel devices. This includes such devices as semiconductor-based photodetectors and bolometers, Magnetic Metallic Calorimeters (MMC), Superconducting Tunnel Junctions (STJ), and Transition Edge Sensors (TES). However, these devices have had limited success in achieving the simultaneous large-scale array sizes and large-bandwidth operation necessary for high-speed, high-resolution detection. To overcome this performance limitation, it is advisable to focus on low-temperature detectors which are intrinsically adapted to giant-array multiplexing and ultra-fast readout. To adopt large scale frequency-domain multiplexing for low-temperature detectors, it is necessary to find detectors which“broadcast” at microwave frequencies. Superconducting microwave resonators naturally lend themselves to this task. One recent demonstration is an implementation known as Kinetic Inductance Detectors (KIDs). This detection mechanism can be adopted for low-energy EM radiation (radio, mm, THz) in continuous mode, or in pulsed mode for higher energy radiation and particles. We present an ongoing development for a KIDs instrument dedicated to millimetric ground-based observations at the 30m IRAM telescope at Pico Veleta. The Neel IRAM KIDs Array (NIKA) project is coordinated in Grenoble and involves groups in Holland (SRON), UK (Cardiff) and Italy (Roma).

Resume Cette etude menee entre 1997 et 2003 en Bretagne sur les pneumocoques responsables d'infections invasives, evalue la sensibilite aux antibiotiques et les serogroupes des souches isolees de bacteriemies, de meningites et d'otites chez les enfants et les adultes. En 2003, 62 % des souches sont de sensibilite diminuee a la penicilline, 11 % sont resistantes. La prevalence des souches resistantes a l'erythromycine atteint 63 %. Ces taux de resistances sont les plus importants dans la population infantile. Les serogroupes 14 et 19 sont les plus frequents, surtout parmi les enfants. L'emergence notable du serogroupe 19 pourrait etre due a l'utilisation du vaccin conjugue heptavalent introduit en France en 2001. La surveillance des pneumocoques reste necessaire pour detecter les serogroupes emergents et les resistances.

Eddy covariance data from four European grassland sites are used to probabilistically invert the CARAIB dynamic vegetation model (DVM) with ten unknown parameters, using the DREAM(ZS) Markov chain Monte Carlo (MCMC) sampler. We compare model inversions considering both homoscedastic and heteroscedastic eddy covariance residual errors, with variances either fixed a~priori or jointly inferred with the model parameters. Agreements between measured and simulated data during calibration are comparable with previous studies, with root-mean-square error (RMSE) of simulated daily gross primary productivity (GPP), ecosystem respiration (RECO) and evapotranspiration (ET) ranging from 1.73 to 2.19 g C m−2 day−1, 1.04 to 1.56 g C m−2 day−1, and 0.50 to 1.28 mm day−1, respectively. In validation, mismatches between measured and simulated data are larger, but still with Nash–Sutcliffe efficiency scores above 0.5 for three out of the four sites. Although measurement errors associated with eddy covariance data are known to be heteroscedastic, we showed that assuming a classical linear heteroscedastic model of the residual errors in the inversion do not fully remove heteroscedasticity. Since the employed heteroscedastic error model allows for larger deviations between simulated and measured data as the magnitude of the measured data increases, this error model expectedly lead to poorer data fitting compared to inversions considering a constant variance of the residual errors. Furthermore, sampling the residual error variances along with model parameters results in overall similar model parameter posterior distributions as those obtained by fixing these variances beforehand, while slightly improving model performance. Despite the fact that the calibrated model is generally capable of fitting the data within measurement errors, systematic bias in the model simulations are observed. These are likely due to model inadequacies such as shortcomings in the photosynthesis modelling. Besides model behaviour, difference between model parameter posterior distributions among the four grassland sites are also investigated. It is shown that the marginal distributions of the specific leaf area and characteristic mortality time parameters can be explained by site-specific ecophysiological characteristics. Lastly, the possibility of finding a common set of parameters among the four experimental sites is discussed.

Resume Treize laboratoires bretons ont collecte 832 souches de Streptococcus pneumoniae en 1999 chez 312 (37,5 %) femmes et 518 (62,2 %) hommes hospitalises ou consultants. Cette population comprenait 255 (30,6 %) enfants. Cent quatre-vingt-huit (22,6 %) souches ont ete isolees d’hemocultures, 16 (1,9 %) de LCR, 449 (54 %) de prelevements pulmonaires qu’ils soient proteges (8,1 %) ou non (45,9 %) et 88 (10,6 %) de pus d’otite moyenne aigue. La diminution de la sensibilite a la penicilline G (PSDP) a ete mesuree par un disque d’oxacilline 5 μg selon les recommandations du CA-SFM. Les CMI de la penicilline G, de l’amoxicilline et du cefotaxime ont ete mesurees sur une partie des PSDP par la methode de dilution en gelose. Soixante-cinq pour-cent (546/832) des pneumocoques sont des PSDP, 33,5 % des PSDP sont resistants a la penicilline G, 2,2 % sont resistants a l’amoxicilline et 0,2 % au cefotaxime. L’activite de l’erythromycine, de la tetracycline et du cotrimoxazole, determinee par diffusion en gelose, confirme l’association de la resistance a ces antibiotiques aux PSDP. Le serotypage des PSDP retrouve les types predominants 23 (23,7 %), 14 (23,5 %) et souligne l’augmentation de frequence du type 19 (19,1 %). Dans notre region, l’augmentation constante des PSDP (1993–1994 : 28,5 % ; 1997 : 56,4 % ; 1999 : 65,6 %) pourrait peut-etre etre expliquee par l’analyse des donnees sociologiques et demographiques specifiques.

Original waveforms and optimized signal processing are proposed for frequency-modulated continuous-wave lidar for range finding, velocimetry, and laser anemometry. For range finding, the aim of this signal processing is to extend lidar range and reduce ambiguities. Moreover, the effect of moderate atmospheric turbulence on lidar efficiency is analyzed for infinite and finite targets, taking into account wind-induced bistatism. For laser anemometry, the aim is to measure air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter and to avoid parasitic echoes coming from clouds or hard targets in the vicinity of a helicopter.

Frequency-modulated continuous-wave lidar is evaluated for range finding, velocimetry, and laser anemometry. An original signal processing and waveform calibration for range finding leads to a reduction of computational effort while preserving capability for long-range measurement. Multiple target distance measurement is also demonstrated. For laser anemometry, the aim is to avoid parasitic echoes in the vicinity of a helicopter and to measure the air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter. Flight tests of this functionality and vortex ring state warning are demonstrated.

Introduction Trois cas de syndrome hemorragique et uremique (SHU) survenus en 15 jours dans une creche etaient notifies a l’Institut de veille sanitaire (InVS) le 5 novembre 2012 suggerant des cas groupes d’infection a Escherichia coli enterohemorragique (EHEC). Methode Une enquete exploratoire, une enquete de cohorte retrospective aupres de 89/94 enfants (95 %) et de 28/36 (78 %) personnels et une surveillance prospective ont ete realisees pour rechercher une exposition commune et determiner l’ampleur de l’epidemie. Un depistage dans l’entourage familial des cas confirmes et parmi les enfants et personnels a ete realise. Les EHEC ont ete recherches par PCR dans les selles, les echantillons positifs etaient mis en culture pour caracterisation des souches. Un cas confirme etait un enfant ou personnel de la creche ayant presente, entre le 10 octobre 2012 et le 17 janvier 2013, des signes de gastro-enterite et/ou un SHU avec isolement de EHEC O111 ; un cas probable avait presente des selles sanglantes et/ou un SHU et une PCR positive ; un cas possible avait presente une diarrhee avec au moins trois selles liquides en 24 heures et consulte un medecin. Resultats Dix-huit cas (6 confirmes, 1 probable et 11 possibles) ont ete recenses parmi les enfants. La courbe epidemique evoquait une transmission interhumaine. Le taux d’attaque etait de 20,2 %, 6,7 % en considerant uniquement les cas confirmes. La frequentation du groupe A etait associee significativement avec la maladie (RR = 3,1 IC95 % [1,3–7,1]). Parmi les contacts familiaux des cas confirmes, 17 % (3/18) etaient porteurs asymptomatiques. Le depistage a identifie 4 % (3/80) d’enfants porteurs asymptomatiques. Discussion Devant les questions soulevees par la gestion, le Haut Conseil de la sante publique a mis en place en juillet 2013 un groupe d’experts pour elaborer des recommandations et eviter la survenue de cas secondaires d’EHEC dans des collectivites.

High hydrostatic pressure treatment is regarded as a possible alternative process for food preservation. One of the primary considerations for industrial applications is the ability of this technique to destroy pathogenic microorganisms. The inactivation of microorganism populations after high pressure treatment is well described, but their residual pathogenicity is less documented. This study compared the virulence of Listeria monocytogenes scott A before and after high pressure treatments. The pressurized samples were composed of 1 ml of Listeria monocytogenes culture diluted into 9 ml of buffer. Two buffers are used: phosphate buffer (pH 7) and citrate buffer (pH 5.6). The virulence of cells is estimated by their association and invasion capacities to Hela cells. These characteristics of pathogenity were compared between untreated and pressurized cells (400 MPa, 10min, in citrate buffer) or (600 MPa, 10min, in phosphate buffer). These results showed that, after treatment in citrate buffer, the...

The existence of a viable but nonculturable (VBNC) state has been described for Campylobacter jejuni as it had been for a number pathogenic bacteria. Three C. jejuni human isolates were suspended in surface water and subsequently entered the VBNC state. After starvation for 30 days, VBNC cells were inoculated in the yolk sacs of embryonated eggs. Culturable cells were detected in a large proportion of the embryonated eggs inoculated with VBNC C. jejuni cells. Recovered cells kept their adhesion properties.

Resume But de l'etude Des spherules de ceramique macroporeuse de phosphate de calcium ont ete evaluees et developpees, avec le double objectif d'obtenir un substitut osseux resorbable et osteoconducteur, et un vecteur d'antibiotiques assurant une delivrance in situ de gentamicine ou de vancomycine. Le but de cette etude est de placer cet implant dans un foyer d'osteomyelite chronique experimental chez le lapin, ce qui permet de s'approcher pour la premiere fois du but de cette experimentation: le comblement des pertes de substance osseuse en milieu septique. Materiel et methode L'experience a ete menee sur 24 lapins et a comporte trois etapes en s'inspirant de la description de Norden. L'induction de l'osteomyelite a ete realisee au niveau de la metaphyse superieure du tibia en injectant un agent sclerosant puis une suspension de Staphylococcus aureus. La maturation ayant ete obtenue en trois semaines, le foyer d'osteomyelite chronique a ete aborde chirurgicalement et curete. Les animaux ont alors ete repartis en trois groupes: un groupe recevant un implant de ceramique chargee en gentamicine; un deuxieme groupe recevant un implant identique, mais sans antibiotique; un troisieme groupe ne recevant aucun implant, considere comme temoin. Les lapins ont ete sacrifies de j2 a j21 de facon a recueillir une information d'ordre cinetique. L'etude a porte sur la colonisation osseuse bacterienne, la concentration osseuse d'antibiotique et la quantite d'antibiotique restant dans l'implant. Les dosages ont ete realises par methode immuno-enzymatique. Resultats L'induction de l'osteomyelite a ete obtenue dans 21 cas sur 24 (87,5 %). La liberation de l'antibiotique a ete totale et precoce (avant le 2 e jour), mais celuici est reste present dans le compartiment intra-osseux jusqu'au 10 e jour. L'etude de la bactericidie a retrouve une efficacite therapeutique probable mais non prouvee. Conclusion Le modele d'osteomyelite experimentale de Norden chez le lapin a permis d'evaluer les traitements par voie generale, mais il est peu adapte a l'etude des biomateriaux. Le protocole experimental le plus interessant serait sans doute l'induction d'un foyer d'osteomyelite chronique chez la brebis, ce qui permettrait de se rapprocher davantage de l'experience humaine.

We have studied the mechanical and pharmacokinetic characteristics of an industrially-prepared bone cement containing 3 g of vancomycin per 60 g cement. A low viscosity cement was selected, to increase contact between the antibiotic and the infected surfaces. Resistance of compression (95 mPa) was well above the required standard (70 mPa) and similar to that of other cements with or without gentamicin. The concentrations in blood, urine and bone were measured in mg/l and mg/kg, and compared to the break point (BP) of susceptibility tests, which must be obtained to achieve control of infection. Diffusion tests were conducted in vitro (elution in saline from rods), and in 30 sheep femora implanted with the cement in vivo. In the animal study, bone levels during the first three months were three-fold higher than the BP (i.e., wereor = 12 mg/l) in 92% of specimens from all areas of bone studied and at all times since implantation; they exceeded five times the BP in 56% of specimens and were never lower than twice the BP. The mean level was four times the BP after six months and fell sharply during the next six months. A pharmacokinetic study in ten patients who had a primary total hip arthroplasty with vancomycin-loaded cement as prophylactic antibiotic therapy showed that blood levels were lower than 3 micrograms/ml, i.e., 30 times lower than the toxic threshold (90 micrograms/ml). Vancomycin was undetectable in urine after the tenth day. The levels in drainage fluids were five times the BP after 24 h and equal to it after four days. None of the ten patients treated prophylactically with vancomycin-loaded cement developed evidence of allergy, toxicity, intolerance or loosening during a two year period. No adverse events were recorded in 17 other patients treated with a vancomycin (2 g) plus gentamicin (0.8 g) loaded cement as adjuvant therapy for severe prosthetic infection.

The read-out electronics of the EDELWEISS-II experiment is presented. Its implementation has been guided by two important design choices. The first one is putting cold electronics far from the detectors in order to attenuate possible background sources from electronic components. It implies strong constraints on noise optimization, line stray capacitance and thermal load. The second one is acquisition of fully digitized signals to minimize the E.M. noises and to take full advantage of digital processing possibilities for filtering and triggering. The resulting amplification scheme is presented for both ionization and heat channel, as well as performances of the full read-out scheme. Future prospects about the coming EDELWEISS-III experiment electronics are also discussed. This updated design takes advantage of the experience gained in previous steps of the experiment while aiming at fulfilling specific constraints of a future ton-scale experiment.

Resume L'evolution de la diminution de sensibilite de Streptococcus pneumoniae aux β-lactamines est suivie, en France, par le Centre National de Reference du Pneumocoque (CNRP). Les resultats d'une enquete regionale retrospective, effectuee dans 13 Centres hospitaliers, ont ete compares aux donnees nationales du CNRP, puis analyses par centre. Le taux moyen de resistance a la penicilline du pneumocoque dans cette region est comparable aux donnees du CNRP (13 %). L'etude montre egalement une nette difference de sensibilite selon que les souches sont considerees invasives (5,5 % de PRP) provenant d'hemocultures, LCR, prelevement bronchique protege ou non-invasives (18,6 %). Une relation entre PRP et recrutement pediatrique est mise en evidence (33 % de PRP chez les enfants). Une heterogeneite de resultats est constatee dans les differents centres incitant a discuter des biais possibles tels que le type des prelevements recus, le recrutement de patients et les methodes d'etude de la sensibilite. Les resultats de cette etude devraient inciter a un suivi epidemiologique homogene local afin de guider les choix therapeutiques.

This prospective study aimed to determine the prevalence of Helicobacter pylori infection in relation to the occurrence and severity of NSAIDs induced gastropathy. A total of 111 patients were studied-66 were taking NSAIDs and 45 were control patients. All patients underwent endoscopy during which antral biopsy specimens were taken to determine H pylori status (Gram and Giemsa staining, urease test, and cultures). The NSAID group comprised: group I, patients without mucosal damage (n = 28); group II, patients with gastropathy (n = 26); and group III, patients with bleeding associated with NSAID induced gastropathy (n = 12). Control patients had neither dyspeptic symptoms nor endoscopic lesions. There were no differences in age, sex ratio, or presence of H pylori (26% v 24%) between the NSAID and the control groups. Among patients taking NSAIDs, H pylori infection was more frequently (p < 0.02) diagnosed in those who presented with gastropathy (groups II and III: 37%) than in those without lesions (group I: 11%). The frequency of H pylori infection increased significantly with the severity of gastropathy (group I = 11%; group II = 31%; group III = 50%; p < 0.03). H pylori infection was associated with chronic active gastritis (group I = 21%; group II = 35%; group III = 67%; p < 0.05). These data suggest that H pylori may be a risk factor of NSAID induced gastropathy.

Low-temperature physics and astronomy have traditionally focused on developing exquisitely sensitive single‐pixel detectors. While this has yielded considerable results, these technologies almost uniformly suffer from an inability to scale to large array sizes. In order to circumvent this barrier, frequency-multiplexing techniques have recently emerged as a suitable solution. Here we present a detailed description of a measurement platform based on frequency-multiplexed superconducting resonators along with the results from two distinct measurements that leverage this nascent technology to achieve multiple-device readout. The first application discussed is a seven-pixel array sensor of the permittivity of liquid helium suitable for quantum hydrodynamic experiments. The second implementation described is a prototype 16-channel mm-wavelength detector optimized for ground-based astronomical detection at the 30 meter Institute for Millimeter-Wave Radio Astronomy (IRAM) telescope in Pico Veleta, Spain.

Zirconia matrix composites, prepared by chemical vapor infiltration (CVI) from preforms (alumina or carbon fibers) having a two- (or pseudo-three-) dimensional character, were studied from a thermal behavior and resistance to oxidation standpoint. The zirconia volume fraction and residual porosity were within the 0.30–0.75 and 0.10–0.25 ranges, respectively. The experiments were carried out up to 1500°C. Thermal expansion is low and almost reversible for the C-ZrO 2 composites whereas it is more significant and partly irreversible for the Al 2 O 3 -ZrO 2 composites. The Al 2 O 3 -ZrO 2 composites exhibit an insulating character above 1000°C, comparable to that of sintered ZrO 2 , whereas the C-ZrO 2 composites have a thermal conductivity equal to that of sintered alumina at T > 1000°C. Finally, the resistance to oxidation by air is acceptable at moderate temperatures and for short exposures. In contrast, under more severe conditions, damaging phenomena occur (i.e. grain growth, oxidation of the carbon preform or BN interphase) which are detrimental to the mechanical behavior.

On the basis of an experimental approach, new ceramic-ceramic composites have been prepared by the CVI of ZrO2 within the pore network of various fibrous preforms. The optimization of the CVI parameters has been carried out on the basis of: (i) a kinetic study (overall mass of deposited zirconia), (ii) mercury porosimetry (actual infiltration ratio, τ i ) and (iii) microprobe analysis (ZrO2 distribution profiles) utilizing mainly transition alumina fiber based substrates. SEM observations of failure surfaces provide evidence of a strong adhesion between alumina and zirconia in alumina fiber composites, and of weak adhesion with delaminations between pyrocarbon and zirconia in two-dimensional carbon-carbon/zirconia composites. From a kinetic point of view, the variation of residual porosity with densification time follows an exponential law. The behavior of different preforms towards the same CVI conditions has been shown to be strongly dependent on the features of the pore network. A low porosity and a low mean pore size are unfavorable to good densification.

This study is the first reported ion mobility detection of ethyl centralite and diphenylamine (DPA) smokeless gunpowder stabilizers, together with the nitroso and nitro derivatives of diphenylamine. First, the applicability of the ion mobility spectrometry (IMS) for the substances of interest was determined. The existence of numerous peaks, both in positive and negative modes, clearly demonstrates the success of these experiments. All mono and di-nitro derivatives of DPA tested were detected with this method. Unfortunately, many of the ions generated were not accurately identified. However, reduced mobility constants representative of each ion generated under defined operating conditions could be used for purpose of compound identification. The method was then successfully tested on real gunpowder samples. By the use of IMS, we managed to establish a rapid, simple and sensitive screening method for the detection and identification of smokeless gunpowder organic components. # 2006 Elsevier Ireland Ltd. All rights reserved.

At this time, many antibiotics have decreased activity against Streptococcus pneumoniae, a major agent of infectious disease. In this study, we evaluated antibiotic susceptibility and serogroups of strains isolated from bacteraemia, meningitis and acute otitis media in adults and children over the 1997-2003 period in Brittany, France. In 2003, 62% of the isolates were not susceptible to penicillin and 11% were fully resistant. The prevalence of erythromycin resistance was 63%. Resistance rates were higher among isolates recovered from children than adults. Serogroups 19 and 14 were the most frequently isolated, especially the 19 one among children. The emergence of this serogroup might be a consequence of the use of heptavalent conjugate vaccine introduced in 2001 in France. Future surveillance after vaccination will be needed to detect emerging serogroups and resistance among S. pneumoniae.

Vibrio hollisae is a pathogenic Vibrio species known to cause gastroenteritis in humans after the consumption of shellfish. All cases of infection reported previously were restricted to the Atlantic and Pacific coasts of the United States. A case of gastroenteritis and bacteremia in a previously healthy 76-year-old man who ate cockles from the Quiberon Bay in Brittany, France, is described. This is the first report of Vibrio hollisae infection in Europe.

Throughout 1999, clinical microbiology laboratories of 13 hospitals in Brittany have recovered Streptococcus pneumoniae isolates in 832 patients, 312 (37.5%) female and 518 (62.2%) male. Two hundred fifty five of them (30.6%) were children. One hundred eighty eight isolates were recovered from blood cultures (22.6%), 16 from CSF (1.9%), 449 from lungs (54%), and 88 from ear exsudates (10.6%).A 5 microgram oxacillin-disk test was used to detect isolates with reduced susceptibility to penicillin G. Determination of MICs of penicillin G, amoxicillin and cefotaxime were then performed by agar dilution method on 402 strains previously categorized resistant or intermediate. Five hundred forty six isolates were PSDP, 33.5% of them were resistant to penicillin G, 2.2% to amoxicillin and 0.2% to cefotaxime. As expected, a decreased susceptibility to beta-lactamins was frequently associated with resistance to macrolides, cotrimoxazole and tetracycline. Among PSDP, the most prevalent serotypes were 23 (23.7%), 14 (23.5%) and 19 (19.1%). In Brittany, the constant rise of PSDP (1993-1994: 28.5%; 1997: 56.4%; 1999: 65.6 %) could be perhaps explain by analysis of social and demographic data.

Erysipleas, also known as Saint Anthony's fire, is an acute infection of the skin caused, in most of cases, by group A streptococci. In the past, the most common site of involvement was the face and, in the pre-antibiotic era, mortality was high. In this retrospective study, we highlight the clinical and bacteriological features and report follow-up in 92 patients hospitalized in an internal medicine unit between 1st March 1992 and 31st December 1996 for 94 episodes of erysipelas. The involvement of the lower limbs predominated as involvement of the face is becoming very rare. Streptococci from others groups and Staphylococcus aureus have been implicated on occasions. Recovery is usual even if this infection may greatly weaken these often fragilized patients. In this paper, antibiotic treatment as well as the place of anticoagulants and Doppler ultrasound are discussed. Hospitalization is often necessary but it must not be systematic.

Macroporous beta tricalcium phosphate ceramic beads were elaborated to be a resorbable bone substitute and a drug delivery system carrying gentamicin or vancomycin. The aim of this study was to evaluate this implant into a rabbit experimental osteomyelitis.Experimentation included 24 rabbits and was performed in three stages, according to Norden's description. Induction of osteomyelitis was obtained by injection of a sclerosing agent and of Staphylococcus aureus through the lateral side of the metaphysis of the proximal tibia. Three weeks after inoculation, animals were randomly dispatched to one of the three treatment groups. After surgical debridment (to collect cinetics data), the first group received no further treatment and was considered as a control; the second group received a ceramic implant; the third group received a gentamicin-loaded ceramic implant. Euthanasia occurred between 2 days and 21 days after the debridment. Bone samples were obtained to quantify the bacterial and gentamicin bone concentrations. Gentamicin level was also measured inside the ceramic implant. Antibiotic concentration was assessed by a immunoenzymatic method.Osteomyelitis was obtained in 21 of the 24 animals (87.5%). Antibiotic release was early and complete (before the third day) but gentamicin still remained in the bone for 10 days. Bacterial concentration suggested an antimicrobial activity of the implant, but not a full sterilisation of the osteomyelitis.Norden's experimental osteomyelitis model with rabbit was proposed to assess the therapeutic activity of systemic antibiotics, but not to evaluate biomaterials. Therefore we have shifted for experimental evaluation of biomaterials to a metaphyseal osteomyelitis in the sheep, the patterns of which are close from those of the human disease.

At elevated osmolarity of the mineral medium M63, marine macroalgae constitute important osmoprotectants and nutrients sources for Escherichia coli. Growth of bacterial population (16 strains) was improved by supplementing M63 salts medium with either aqueous or ethanolic algal extracts obtained from Ascophyllum nodosum, Fucus serratus, Enteromorpha ramulosa, Ulva lactuca, and Palmaria palmata. In their presence, growth was still observed even at 1.02 M NaCl. Furthermore, the E. coli ZB400 growth in presence of whole macroalgae thalli in M63/0.85 M NaCI reached its maximum within 24 h (5 × 10(7) - 5 × 10(8) colony-forming units [CFU] per milliliter). In the presence of A. nodosum, bacterial growth was inhibited. In the same experimental conditions, ethanolic extracts improved E. coli growth significantly, because the yield reached 10(11) CFU per milliliter. Ulva lactuca and P. palmata allowed the better growth. The Dragendorff-positive compounds extracted from bacterial cells growing on each ethanolic extract exhibited an osmoprotective effect as proved by a disk-diffusion assay. On the other hand, the -onium compounds (quaternary ammonium [betaines] and tertiary sulphonium) and total free amino acid contents of U. lactuca ethanolic extracts were higher than in others. Fucaceae extracts demonstrated especially high protein content. Algal extracts constitute not only an appreciable osmoprotection source for E. coli but also nutrient sources.

A fifteen-month-old child was admitted with a week history of isolated fever. On CSF (Cerebral Spinal Fluid) examination, hyperproteinorachy, hyperglycorachy and hypochlorurachy were found. The diagnosis of tuberculosis meningitis was suspected but usual tests were unable to find Mycobacterium tuberculosis in CSF, urine and sputum. Only the Polymerase Chain Reaction detected the Mycobacterium tuberculosis genome in the CSF. A specific treatment was started immediately. Apyrexia was obtained within 2 days; the outcome was favorable, without sequelae.

The authors have evaluated the risk of neonatal infection (NNI) by materno-fetal contamination when a rise in temperature occurs in labour and they have worked out the prophylactic measures that should be taken. This has been the results of a prospective study carried out on 6305 deliveries. Any significant conditions associated with NNI are stained liquor and a low Apgar score at birth. When high temperature develops in labour it is important to deliver the infant as quickly as possible particularly if the labour is a premature one. Prevention carried out by very early diagnosis of amniotic fluid infection in pregnancy and by careful attention to the high risk conditions of: early rupture of the membranes, a high level of vaginal infection particularly with Beta streptococci.

The microhemagglutination-Treponema pallidum (MHA-TP) was automated with the Biomek 1000 workstation (Beckman). 3,000 serum specimens were studied with manual and automated procedures. Thirty nine serum specimens were found positive by both techniques, neither false positive nor false negative results were observed with the Biomek 1000 workstation. The statistical analyse showed no differences between the two procedures, variations were observed only with low titer sera. In conclusion, time saving and augmentation of productivity obtained by automation of this method could be interesting for a microbiology laboratory.

Twenty four strains of coagulase-negative staphylococci from clinically significant blood cultures were separated in four groups on the basis of oxacillin susceptibility and phenotype of resistance to aminoglycoside antibiotics. Susceptibility testing included disk diffusion testing, M.I.C. and M.B.C. determinations and finally, measurements, at sequential times (from 0 to 6 hours), of the bactericidal effect of aminoglycosides alone or combined with oxacillin or vancomycin. Aminoglycosides clinical use (gentamicin, netilmicin, tobramycin and amikacin) exhibited an efficient early bactericidy over the sensitive strains to any tested aminoglycosides and to oxacillin (group 1, 13 strains). When strains having a phenotype of resistance to kanamycin and neomycin (group 2, 4 strains) or kanamycin and tobramycin (group 3, 2 strains) were considered, amikacin inefficiency was assessed by time-killing assay even though disk diffusion testing as well as M.I.C. and M.B.C. determinations failed to demonstrate it. In the same way, only bactericidy measurements indicated the lack of activity of amikacin or netilmicin over strains exhibiting a phenotype of resistance to gentamicin plus kanamycin and tobramycin (group 4, 5 strains). Netilmicin appeared as the most active aminoglycoside over the strains studied. Crude results of disk diffusion testing might appear as an oversimplification, especially when coagulase-negative staphylococci are considered; the early-bactericidy assay findings were stressing for the need of interpreting the results of antibiotic testing on the ground of resistance mechanisms.

Journal de Gynecologie Obstetrique et Biologie de la Reproduction - Vol. 33 - N° 4 - p. 352

Chemical vapour deposition (CVD) of zirconia, from a ZrCl4H2CO2Ar gas mixture, has been studied experimentally. On the basis of a kinetic approach, the deposition process is shown to be governed by chemical reactions (probably water formation) with an apparent activation energy of about 100 kcal mol−1. With an increase in the total gas flow rate and the total pressure, the occurrence of an important homogeneous nucleation in the gas phase (“soot” formation) cannot be prevented. The deposited zirconia films are found to be polycrystalline. A structural analysis by X-ray diffraction shows the possibility of depositing both monoclinic and tetragonal modifications of zirconia; such a mixture remaining stable down to room temperature. By Raman spectroscopic analysis, a small amount of weakly graphitized free carbon can be detected in the deposited films, depending on the deposition parameters. The stabilization of the tetragonal phase, at room temperature, can be explained on the basis of the effect of grain size, which has been thermodynamically studied by Lange et al..

Chemical vapour deposition of zirconia from the ZrCl4CO2H2Ar system is investigated, from a thermodynamic point of view, as a function of initial gas composition, total pressure and temperature, including the influence of the nature of the substrate. On an inert substrate, pure zirconia is deposited with a 100% yield when water is in excess at equilibrium and carbon-zirconia codeposition can be obtained for hydrogen-rich initial compositions. Under conditions for ZrO2 yields close to 100%, a carbon substrate is found to be oxidized while a mullite one is thermodynamically stable.

The mechanical behavior of various zirconia-based fibrous composites has been studied at ambient and high temperatures. The composites were prepared by ZrO2-CVI densification, from preforms made of alumina or carbon fibers consolidated with a small amount of alumina, pyrocarbon or hex-BN. When loaded under compression at room temperature, 2D-C-C/ZrO2 composites exhibit mechanical behavior similar to that already reported for the related 2D-C-C/SiC, 2D-C-C/B4C, 2D-C-C/TiC or 2D-C-C/BN materials with: (i) a linear elastic domain, (ii) a damaging domain prior to failure and (iii) an anisotropy which decreases as V(ZrO2) is raised. Under three-point bending, the alumina-zirconia composites behave, at room temperature, in a non-brittle manner when the preform has been consolidated by BN, with crack deviation and pull-out phenomena. The variations of the stiffness and strength versus V(ZrO2) obey exponential laws at room temperature. Finally, the alumina-zirconia composites keep their strength and rigidity up to about 1000°C under an atmosphere of argon/hydrogen.