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Regarding the need of developing a low-cost and portable tool for monitoring and tracking fish quality in real time, we successfully developed a portable gas detection system based only on 5 metal oxide chemical sensors for blue fish freshness monitoring. The variability of the sensing features of the 5 sensors towards the analyzed fish samples (Sardines, Chinchard and Mackerel) was coupled to data classification methods in order to discriminate between the different evolution stages of Agadir blue fish freshness during 10 storage days, in accordance with international standards.

International audience; In this paper, a simple home-made Forcespinning system was designed and successfully applied for the production of different metal oxide ultrafine tubes such as SnOx and ZnO. The morphology, purity, crystallinity and porosity of the forcespun samples were investigated by SEM, XRD, and EDS, TGA, and BET analysis. The samples were deposited unto a microsensing platform and their gas-sensing properties against different hazardous vapors such as ethanol, acetone and benzene were studied through preliminary tests at different detection temperatures. The results revealed different sensing behaviors of the prepared sensors towards the different vapors. Interestingly, the gas sensor based on SnO x exhibited a higher and faster sensor response towards ethanol at 180°C as operating temperature. On the other hand, ZnO presented a higher response to acetone at 250°C. The ability of the prepared sensors to discriminate between the different vapors was explored.

Tungsten oxide thin films are grown by DC reactive magnetron sputtering combining glancing angle deposition (GLAD) and reactive gas pulsing process (RGPP). Inclined, zigzag and spiral columnar architectures are produced with various oxygen injections during the growth. The dodecane and ozone sensing properties of these tungsten oxide nanostructured active layers are comparatively studied with that of films deposited by conventional sputtering process. Microstructure, morphologies and electrical behaviors are characterized as a function of the growing conditions. As-deposited films systematically exhibit an amorphous crystal structure with a porous microstructure, which depends on the GLAD architecture. Annealing at 300 °C in air for 12 h leads to a polycrystalline structure keeping voided networks. Dodecane and ozone sensing performances are the most significant for inclined columnar architectures but they also depend on the RGPP sputtering conditions. As a result, the GLAD + RGPP combination proves to be a relevant strategy for the fabricating tungsten oxide nanostructured films as active layers with an attractive potential for gas sensors.

International audience; The aim of this work was to identify a nanoporous material able to trap toluene traces in order to develop a gas detection device for indoor air quality monitoring or biomedical diagnosis. A set of various adsorbents such as zeolites and activated carbon microspheres was studied here. First a detailed characterization of their porous properties was performed by nitrogen adsorption. Then adsorption of toluene and other interfering compounds which can selectively adsorbed with it, such as water and carbon dioxide, was studied in order to select the most suitable material. Results revealed that the activatedcarbon microspheres W5 and the zeolite NaY, which exhibit high specific surface areas and large micropore volumes, are the best adsorbent materials to capture toluene present at very low concentration in the gas phase.

6 Figuras, 3 Tablas.-- Material suplementario disponible en línea en la página web del editor.-- © 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/, Interesting sensing performances of indoor formaldehyde pollution were obtained when small amounts of zinc were introduced in tin oxides. Nanostructured Sn oxide-based porous materials doped with Zn or not, were synthesized using hydrothermal routes. The physicochemical properties of the as-prepared metal-oxide materials were characterized using nitrogen adsorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Gas sensors were prepared using the aforementioned tin oxide materials and they exhibited a high sensitivity to formaldehyde at 230 °C, as well as a good repeatability over the time. Their limit of formaldehyde detection was as low as 8 ppb in dry air and 50 ppb in air with 60% RH at 25 °C. These results were much better that those reported in the open literature and they were attributed to both higher area BET, around 180 m2/g, and smaller crystallite size, 3.1 nm., The IJL research team gratefully acknowledges the financial support of the CPER 2007–2013 “Structuration du Pôle de Compétitivité Fibres Grand’Est” (Competitiveness Fibre Cluster), through local (Conseil Général des Vosges), regional (Région Lorraine), national (DRRT and FNADT) and European (FEDER) funds. Part of this work was also supported by CHEERS and TALiSMAN projects (FEDER funds). Dr. Angela Sanchez - Sanchez acknowledges the University of Lorraine, the Region Lorraine and the CNRS for financing her postdoctoral contract.

International audience; The epidemiology of human Salmonella enterica infections in Guadeloupe (French West Indies) appears to be specific, with a higher prevalence of the subspecies enterica serovars Panama and Arechavaleta (Panama and Arechavaleta) than in other regions. A study was performed in Guadeloupe to identify the reservoir of Salmonella serovars by comparing their distribution in warm- and cold-blooded animals and in humans living in Guadeloupe and mainland France. Furthermore, a case-control study was conducted in 2012-2013 to identify the main epidemiologic risk factors for S. enterica infection among children under 15 years of age. Between June 2011 and December 2014, feces from 426 reptiles (322 anoles, 69 iguanas and 35 geckos) and 50 frogs distributed throughout Guadeloupe and nearby islands were investigated. The frequency of S. enterica carriage was 15.0% (n = 64) in reptiles but varied by species. The only significant risk factor for S. enterica infection was a more frequent presence of frogs in the houses of cases than in those of controls (P = 0.042); however, isolates were not collected. Panama and Arechavaleta were the two serovars most often recovered between 2005 and 2014 from humans living in Guadeloupe (24.5% (n = 174) and 11.5% (n = 82), respectively), which is in contrast to the low prevalence in mainland France (0.4%). Their presence at low frequencies in wild reptiles (4.6% (n = 3) and 3.1% (n = 2), respectively) and pigs (7.5% (n = 5) and 1.5% (n = 1), respectively) suggests a broad host range, and humans may be infected by indirect or direct contact with animals. These serovars are probably poorly adapted to humans and therefore cause more severe infections. The unusual subspecies houtenae serovar 43:z4,z32:- was a major subspecies in wild reptiles (24.6%, n = 16) and humans (9.4%, n = 67) but was not recovered from warm-blooded animals, suggesting that reptiles plays a key role in human infection.

The misuse of alcohol has harmful social and health impacts within a population. The French military must be particularly vigilant with alcohol, due to specificities linked with weaponry. This study was designed to explore social representations of alcohol based on a sample of the French Navy in order to prioritize prevention focuses on alcohol misuses in a military environment.A semi-directed interview-based exploratory study was conducted in the south of France at the end of 2015. Data was submitted to manual categorical analysis and textual analysis (Iramuteq software).Sixty-two marines from the French Navy were interviewed including 30 Navy and 32 Marine Firefighters. Data analysis indicated that the motivation to consume alcohol comes more from a social influence (extrinsic motivations) than for pleasure induced by alcohol effects (intrinsic motivations). For Navy personnel, the sense of belonging to the Navy is strengthened by drinking habits with a strong social cohesion. In contrast, the Marine Firefighters had a negative perception of alcohol because of a possible degradation of their professional image for the civilian population.The identification of social representations of alcohol allows for a better apprehension of drinking behavior within a French military population, particularly by focusing on content and organization of discourses about alcohol. Following this survey, a quantitative study is currently being drawn up among military personnel from the French Navy in order to clarify some of the elements identified and presented within this article.

International audience; Matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a clinical microbiology tool for the systematic identification of microorganisms. It has recently been presented as an innovative tool for the rapid and accurate identification of mosquitoes and their blood meal. To evaluate the capacity of this tool to identify mosquitoes collected in a tropical environment and preserved with silica gel, we analyzed 188 mosquitoes of different species collected in Chad, which were preserved with silica gel for 2 months. The MALDI-TOF MS analysis correctly identified 96% of the mosquitoes and 37.5% of their blood meals. Using MALDI-TOF MS and molecular biology, eight mosquito species were identified, including Anopheles gambiae s.l., Anopheles rufipes, Culex quinquefasciatus, Culex neavei, Culex pipiens, Culex perexiguus, Culex rima, and Culex watti. Blood meal identification revealed that mosquitoes fed mainly on humans, birds, and cows. Matrix-assisted desorption/ionization time-of-flight mass spectrometry appears to be a promising, fast, and reliable tool to identify mosquitoes and the origin of their blood meal for samples stored with silica gel.

International audience; Tungsten oxide thin films exhibiting an oriented columnar architecture were prepared by reactive co-sputtering. Two opposite W and WO3 targets focused on the center of the substrate were simultaneously sputtered using opposite and oblique angles of 80° from the substrate normal. The reactive gas pulsing process was used to adjust the films electrical resistivity. Different inclined columnar structures were produced and applied as gas sensors for dodecane detection. Morphology, structure and resistivity of the films were investigated and connected to the sensing performances measured from 373 to 773 K.

International audience; Background: Public health is a multidisciplinary activity whose fields of action are acquiring an increasingly broad. The Service de santé des armées (SSA) has always had a culture of public health problems thanks to doctors specialized in the treatment of major diseases. Often involved in public health activities, health professionals nevertheless have a fragmented vision. The objective was to describe the social representations of public health of military healthcare workers.Method: The responders were doctors, nurses, veterinarians and pharmacists practicing in different areas of SSA (caregivers, administrators, policy makers) and were interviewed by telephone. A question of spontaneous evocation on the representations of public health in the army was asked. The overall lexical analysis was performed according to the method of rank-frequency. Categorical analysis was conducted to better understand the whole lexical field use.Results: There were 90 responders. The most salient terms were “prevention, epidemiological surveillance and vaccination”. The categorical analysis showed that doctors used a lexical field primarily focused on diseases and risk behaviors, nurses on the specifics of military surveillance and policy makers about the cross-discipline.Conclusion: Public health in the army is mainly represented by epidemiological surveillance and prevention. Given the non-mentioned fields, a strengthening of communication on the current challenges of public health would probably improve adherence of healthcare professionals since public health takes on more and more importance in the development of the national health policy and management of health crises.; Position du problème: La santé publique est une activité multidisciplinaire dont les champs d’action sont de plus en plus nombreux. Le Service de santé des armées (SSA) a toujours eu une culture de la santé publique grâce notamment aux médecins des grandes endémies. Souvent impliqués dans des activités de santé publique les professionnels de santé en ont pourtant une vision parcellaire. L’objectif était de décrire les représentations sociales de la santé publique des professionnels de santé militaires.Méthode: Les répondants étaient des médecins, infirmiers, vétérinaires et pharmaciens exerçant dans les différents domaines du SSA (soignants, administratifs, décideurs) et ont été interrogés par téléphone. Une question d’évocations spontanées portant sur les représentations de la santé publique dans les armées leur a été posée. L’analyse lexicale globale a été effectuée selon la méthode des rang-fréquence. Une analyse catégorielle a été réalisée pour mieux appréhender l’ensemble du champ lexical utilisé.Résultats: Le nombre de répondants a été de 90. Les termes les plus saillants étaient « prévention, surveillance épidémiologique et vaccination ». L’analyse catégorielle a montré que les médecins des forces avaient un champ lexical principalement axé sur les maladies et les conduites à risque, les infirmiers sur les spécificités de la surveillance militaire et les décideurs sur la politique de santé et l’organisation des systèmes.Conclusion: L’image de la santé publique dans les armées est représentée essentiellement par la surveillance et la prévention. Compte tenu des champs d’activités non évoqués, un renforcement de la communication sur les défis actuels et la valorisation des activités de la santé publique permettrait sans doute d’améliorer l’adhésion des acteurs à leur mission de santé publique, au moment où elle revêt une importance majeure dans le développement des politiques de santé et dans la gestion des crises sanitaires.

International audience; The analysis of exhaled volatile organic compounds (VOCs) related to lung cancer is a very promising wayin medical diagnosis because it is non-invasive and much less expensive than traditional medical analysisused so far. In that sense, a silicon micro-analytical platform consisting of a micro-preconcentrator cou-pled to a silicon spiral gas chromatographic micro-column was built, and a metal oxide-based gas sensorwas used as a miniaturized gas detector. This micro-fabricated device was successfully tested to selec-tively detect low concentrations of VOCs considered as lung cancer biomarkers, within a few minuteseven in presence of high concentrations of water vapor and carbon dioxide.

International audience; In the last decade, the Chikungunya and Zika virus outbreaks have turned public attention to the possibility of the expansion of vector-borne infectious diseases worldwide. Medical entomology is focused on the study of arthropods involved in human health. We review here some of the research approaches taken by the medical entomology team of the University Hospital Institute (UHI) Mediterranee Infection of Marseille, France, with the support of recent or representative studies. We propose our approaches to technical innovations in arthropod identification and the detection of microorganisms in arthropods, the use of arthropods as epidemiological or diagnostic tools, entomological investigations around clinical cases or within specific populations, and how we have developed experimental models to decipher the interactions between arthropods, microorganisms, and humans.

Introduction During the 2014-15 Ebola virus disease (EVD) outbreak in West Africa, French armed forces were involved in the treatment and management of Ebola patients in Guinea. The constant flow of military personnel returning from their deployment posed a risk of secondary dissemination of the Ebola virus. Our objective was to describe the follow-up of returning service members that was implemented to prevent this risk of dissemination in France. Method For the French military, a specific complementary follow-up was added to the national monitoring to take into account the need for a detailed record for follow-up of returning military personnel and to keep the military chain of command informed. Results All the 410 service members deployed in Guinea underwent monitoring among whom 22 were suspected of EVD. Three of them were considered as possible EVD cases but none of them was tested positive for EVD. Conclusion The monitoring organized for French service members deployed in Guinea made it possible to follow all exposed military personnel after their return, know their health status on a near real-time basis and be aware of all alerts. To reach this goal the collaboration with French national health agencies was necessary and should be improved in the future.

A silicon micro-analytical platform consisting of a micro-preconcentrator based on a hydrophobic zeolite, coupled to a silicon spiral micro-column was built. A chemical gas sensor acted as a miniaturized gas detector. This system allowed selective detection of orthonitrotoluene (ONT), an explosive-related compound at the sub-ppm level (365 ppb) in the presence of toluene and moisture.

In this paper, we investigate the feasibility of La1-xAgxCoO3-α nanowires by reactive magnetron sputtering. After a short description of the experimental and hydrocarbon sensing bench devices, a first part will be dedicated to the chemical, microstructural and structural characterization (SEM, XRD,...) of the coatings. As deposited coatings are amorphous and a post heat-treatment under air at 873 K is necessary to crystallise them in the perovskite structure. Finally, the performance as dodecane-sensors of these coatings with amorphous and crystalline structures will be discussed depending on dodecane concentrations and sensitive surfaces temperature and will be compared to those of La0.40Sr0.15Ag0.45CoO3-α nanowires.

The detection of explosives and explosive-related compounds is of major importance for the monitoring of explosive- contaminated sites. Current methods need to become cheaper and portable while maintaining a high sensitivity and selectivity level. In that sense, a silicon micro-analytical platform consisting of a three-dimensional micro-preconcentrator based on a hydrophobic zeolite, coupled to a silicon spiral micro-column was built. A chemical gas sensor acted as a miniaturized gas detector. This system allowed selective detection of orthonitrotoluene (ONT), an explosive-related compound at the sub-ppm level in the presence of toluene and moisture.

Tungsten oxide WO 3 thin films were prepared by dc reactive magnetron sputtering. The GLancing Angle Deposition (GLAD) technique was implemented to transform the typical dense microstructure into an inclined columnar and porous architecture. The incident angle α of the sputtered particles was 0° and 70° leading to a column tilt angle β of 0° and 40°, respectively. Conventional and inclined WO 3 films were sputter deposited on a commercial hotplate system. Ozone gas was periodically injected from 0 to 220 ppb and the variation of electrical conductance of the system was measured vs. time at 250 °C. The conventional WO 3 films exhibited a significant change of electrical conductance as a function of the ozone injection. GLAD WO 3 films with a columnar angle β =40° were even more sensitive to the ozone pulses and the speed of response or recovery was significantly enhanced. This ozone detection improvement was mainly attributed to the more porous structure of WO 3 films produced by the GLAD method.

This paper reports results of dodecane-sensing studies with double-substituted LaCoO3perovskite oxide nanowires. La0.40Sr0.15Ag0.45CoO3-αnanowires were co-sputtered from metallic La, Sr, Ag and Co targets in the presence of a reactive argon-oxygen gas mixture. As deposited coatings are amorphous and crystallise in the perovskite structure after annealing at 873 K for 2 hours under air. Electrical response of the La0.40Sr0.15Ag0.45CoO3-αnanowires was measured at different temperature under air and under air containing 1 to 100 ppm (v) of dodecane vapour. The electrical signal of the nanowires was found to be high and it was possible to detect low concentrations of dodecane (under 5 ppm (v) ) at 573 K.

This paper deals with the development of SnO 2 -based thin sensitive layers dedicated to ozone detection at ambient temperature. Working at ambient temperature drastically differs from the results reported in literature concerning the need of working at high temperature (about 350 °C) for achieving the detection of ozone using tin-dioxide-based gas sensors. The sensitive layers developed in the framework of this study were elaborated using the sol–gel process following aqueous or organic way. Compared to those obtained from the aqueous way, the layers synthesized following the alcoholic way showed high response to O 3 (58 ppb) when the detection was performed at ambient temperature. The results of the physico-chemical characterization and ozone detection using both layers led to the proposition of an ozone detection mechanism using tin dioxide-based gas sensors.

FONDECYT FONDECYT

International audience; A metal-containing polymer has been prepared by electropolymerization of an homoleptic Ru(II)-terpyridine complex bearing pyrrole heterocycles. The polymer is obtained as a thinfilm at the surface ofelectrodes, and has been characterized by electrochemical measurements, XPS and microscopy. It hasbeen shown that this polymer acts as an active gas sensitive layer since it enables the detection of anammonia gasflow through layer’s resistivity measurements.

In the present study, we present the first steps of the development of a low power consumption GC microsystem for the analysis of benzene in the presence of butadiene, involved in petrochemical industrial applications. This system is made by coupling a low power consumption planar microhotplate based on a preconcentrator with good preconcentration capability and a spiral microchromatographic column that presents a separation capability of both compounds at room temperature, when tested in front of a gas sensor. The first characterization results of the device showed a successful injection of benzene and butadiene when placed in front of the micro-separation module.

International audience; To strengthen active dengue surveillance in Saint Martin and Saint Barthélemy, two French Caribbean islands, we evaluated the epidemiological usefulness of collecting blood samples from NS1-positive dengue patients on filter paper to identify the dengue serotypes circulating in these regions during a 27-month period. This approach allowed dengue serotypes to be identified by reverse transcriptase-polymerase chain reaction in 90.1% of the total set of 666 samples analyzed and, in 95.5% of the samples collected during the acute phase of the disease. This prospective virological surveillance using blood samples absorbed onto filter paper, which were stored at 4°C and shipped at ambient temperature to a specialized laboratory for analysis, allowed us to avoid the logistic and financial costs associated with shipping frozen venous blood samples. This surveillance system offers a low-cost alternative for reinforcing dengue prevention in areas where specialized laboratories do not exist, notably by facilitating the early detection of potentially new dengue serotypes.

International audience; Tin dioxide-based gas sensors are very efficient devices for the detection of hydrogen fluoride in trace levels since amounts lower than 50 ppb can be detected. Considering the working temperatures of tin dioxide-based gas sensors which are included between 25 and 500 ◦C, the best sensitivity was obtained when the sensor's temperature was maintained at 380 ◦C. In order to explain why high sensitivity is obtained for this temperature and then to understand the reactional mechanism between HF molecules and tin dioxide surfaces, X-ray photoelectron spectroscopy investigations were performed on tin dioxide samples treated with HF vapors at temperatures ranging from 200 to 500 ◦C. For this temperature range, the comparison between the electrical response curves and the XPS characterization, led to the consideration of two separate temperature ranges, where the interaction mechanism between HF and SnO2 can be explained. For temperature lower than 380 ◦C, the adsorption of HF induces the formation of surface hydroxyl groups and SnF4 species. In that case, the electrical conductance of the sensitive material gradually increases. Beyond this temperature, water vapors desorb from tin dioxide surfaces and then the electrical conductance is lowered. Finally, for both ranges of temperatures, the interaction mechanism occurring at the gas/detector interface is proposed.

International audience; Background: The use of 2 live attenuated vaccines (LAV) is recommended to be simultaneous or after an interval of at least four weeks between injections. The primary objective of this study was to compare the humoral response to yellow fever (YF) and measles vaccines among children vaccinated against these two diseases, either simultaneously or separated by an interval of 7-28 days. Subjects and methods: A prospective, multicenter observational study was conducted among children aged 9-15 months. The primary endpoint was the occurrence of positive yellow fever antibodies after YF vaccine by estimating the titers of neutralizing antibodies from venous blood samples. Children vaccinated against YF 7-28 days after receiving the vaccine against measles (test group) were compared with children vaccinated the same day against these two diseases (referent group). Results: Analysis was performed on 284 children. Of them, fifty-four belonged to the test group. Measles serology was positive in 91.7% of children. Neutralizing antibodies against YF were detected in 90.7% of the test group and 92.9 of the referent group (p =0.6). In addition, quantitative analysis of the immune response did not show a lower response to YF vaccination when it took place 1-28 days after measles vaccination. Discussion: In 1965, Petralli showed a lower response to the smallpox vaccine when injected 4-20 days after measles vaccination. Since then, recommendations are to observe an interval of four weeks between LAV not injected on the same day. Other published studies failed to show a significant difference in the immune response to a LAV injected 1-28 days after another LAV. These results suggest that the usual recommendations for immunization with two LAV may not be correct. Conclusion: In low income countries, the current policy should be re-evaluated. This re-evaluation should also be applied to travelers to yellow fever endemic countries.

International audience; The analysis of volatile organic compounds (VOCs) that are linked to lung cancer is a very promising way in medical diagnostics because it is non-invasive and potentially inexpensive. In that sense, a silicon micro-analytical platform consisting of a three-dimensional micro-preconcentrator coupled to a silicon spiral gas chromatographic micro-column was built. A metal oxide-based gas sensor acted as a miniaturized gas detector. This system allowed selective detection of VOCs at the sub-ppm level. The present study is focused first on the chromatographic air analyzer fabrication and second on the selection of an appropriate adsorbent. Various adsorbents such as activated carbon microspheres and zeolites were then studied in order to identify the best material for the concentration of one representative lung cancer biomarker: toluene.

This paper deals with the detection of dimethyl methylphosphonate (DMMP), using tin dioxide-based gas sensors. One of the characteristics of this device is the functioning temperature, which ranges between 25 and 500 °C. The results presented in the first part of this paper concern the study of the thermal degradation of DMMP vapours, in particular the identification and quantification of light and heavy degraded compounds by several analysis techniques (IR, NMR, GC). The second part of this paper is dedicated to the interpretation of the gas sensor's responses during the detection of DMMP and the determination of the origin of the electrical response of the sensor. Finally in the third part of this paper, we propose a reactional mechanism which describes the interactions between DMMP vapours and SnO2 surface, that occurs during the detection of this phosporous compound.

This research concentrates on the sensitivity of a tin dioxide-based gas sensor semiconductor with respect to hydrogen fluoride in the atmosphere. This paper is focused on the development of a separation micro-system, which will be positioned in front of the gas sensor, for the potential use in a complex atmosphere. This study deals with the use of traditional techniques of micro-machining on silicon substrates to manufacture chromatographic micro-columns. The manufacture of the micro-channels and formulation of the stationary phase are discussed. Infrared spectroscopy allows following the evolution of the stationary phase with respect to time. We evaluate the thickness of the stationary phase deposited on the GC micro-channel's internal walls close to the micrometer. A solvent extraction test was performed in order to illustrate the use of the device considered.

Tin dioxide-based gas sensors were laid out at the exit of a chromatographic column for the selective detection of hydrogen fluoride in the atmosphere. After having selected a stationary phase adapted to this particular molecule, the sensor's signals were studied using various experimental parameters. In this paper a complete description of the experimental device and of the electrical responses is given. For the experiment, the gas sample was formed by a gas mixture of HF, O2 and N2. It was found that the optimal mode of detection corresponds to the sensitive element (SnO2) having a temperature near to 500 °C with a carrier gas of oxidising nature (synthetic air). Moreover, it was found that with this experimental configuration, a minimum concentration of about 0.8 ppm was detectable.

An Antopol-Goldman lesion or subepithelial pelvic hematoma of the kidney is a rare cause of hematuria. We described a 26 year-old man hospitalized for macroscopic hematuria associated with a subepithelial hematoma whose development might have been favored by arterial hypertension secondary to a renal artery stenosis.

This research concentrates on the sensitivity of semiconductor tin dioxide-based gas sensors to hydrogen fluoride in air. After evaluating the characteristic detection temperature, the sensor's signals were studied for different HF concentrations. Despite the corrosive effects of hydrogen fluoride, a reproducibility of the signal was found. Likewise, we did not observe any long-term degradation to the sensor. For the experiment, the sensor was exposed to a gas mixture formed by HF, O 2 , N 2 with a constant flow rate of 150 ml min −1 . The semiconductor gas sensor reached maximum sensitivity near 380 °C, and a minimum concentration was detected approximately 50 ppb. Moreover, the detection phenomenon appears to be reversible when considering the electrical response under a constant air flow.

Tin dioxide-based gas sensors make it possible to detect diethyl methyl phosphonate vapors (DEMP). However, the responses present drifts that can be observed vs. time. Such a problem raises the question of the reliability of these devices. The results presented in this article are two-fold: first, they are concerned with the study of the thermal degradation of DEMP by thermal degradation in an oxidizing atmosphere, and second, they are involved in the characterization of the chemical degradation on the tin dioxide-based gas sensors. Gas chromatography and infrared spectroscopy shows that, from 300 °C on, the thermal degradation of DEMP leads to the formation of ethylene (gas phase) and ethyl methyl phosphonic acid (condensed phase). Given that thermal degradation may occur at the sensor's surface, which can reach temperatures as high as 500 °C, these results showed that responses obtained using the DEMP vapors are principally due to ethylene and the drift in the responses vs. time is probably due to the adsorption of phosphorous compounds to the sensor's surface. The aim of this article is to describe the reactional mechanism of the DEMP interaction at the surfaces of tin dioxide-based sensors for temperatures ranging from 200 to 500 °C.

Dear Sir We have read with interest the article by Bricknell et al [1][1] previously published in this journal and we would like to continue this debate by reporting the French Defense Medical Service (DMS) experience in a similar position in Guinea and the role of Force Health Protection (FHP).

This paper deals with the detection of an organosulphur compound, the thiodiglycol (TDG), using tin dioxide-based gas sensors. This compound is thermally unstable. The fact that tin dioxide-based gas sensors have working temperatures that can reach 600°C could be the cause of misinterpretations concerning the response obtained during the detection of TDG vapours. The results presented in the first part of this paper concern the study of the thermal degradation of TDG vapours with, in particular, the precise identification and quantification of light degraded compounds by gas chromatography. Next, the results are linked to the interpretation of the gas sensor’s electrical response during the detection of TDG. In order to understand this response, each degraded compound must be analysed in order to obtain its contribution to the overall electrical response.

Infection is a major complication associated with combat-related injuries. Beside immobilization, wound irrigation, surgical debridement and delayed coverage, post-injury antimicrobials contribute to reduce combat-related infections, particularly those caused by bacteria of the early contamination flora. In modern warfare, bacteria involved in combat-related infections are mainly Gram-negative bacteria belonging to the late contamination flora. These bacteria are frequently resistant or multiresistant to antibiotics and spread through the deployed chain of care. This article exposes the principles of war wounds antimicrobial prophylaxis recommended in the French Armed Forces and highlights the need for high compliance to hygiene standard precautions, adapted contact precautions and judicious use of antibiotics in French deployed military medical treatment facilities (MTF).

A copolymer of polyethylene–polypropylene (PP/EPR) was irradiated using alpha particles under three different atmospheres. First, samples were irradiated by alpha particles (4.3 MeV) in a gas-tight chamber under either dry or moist air. Next, irradiation was carried out under a 4×10−4 Pa vacuum. Pristine and treated sample surfaces were studied by Attenuated Total Reflectance infrared spectroscopy (FT-IR/ATR). It was possible to ascertain that the chemical modifications produced differ according to the atmosphere during irradiation. Under vacuum, vinylic bonds were created. In moist air, carbonyl bonds were formed; and in dry air, both kinds of bonds were produced. In each case, a decrease in the number of CH bonds after irradiation was noted. As polypropylene is widely used in the automobile industry for parts like dashboards and bumpers, this study could be useful for many of the industry's applications. Indeed, it has been determined that, along with chemical modifications generated from the surface of the irradiated copolymer, an increase in its surface free energy results in greater wettability to certain liquids, such as water, formamide and diiodomethane.

The appearance of white deposits on some ceramic products is known as efflorescence. In this study, efflorescence is principally made up of hydrated calcium sulphate. This salt is mainly formed during the firing of the material and is affected by various parameters: firing cycle, material texture and mineralogical and chemical composition of the raw materials. Evidence for this formation is found by analyzing gases evolved during firing: SO2 (from pyrite oxidation) and CO2 (from decomposition of CaCO3). The retention of SO2 is essential in the CaSO4 formation. Fourier transform infrared (FTIR) analysis of CaCO3 reacting with SO2, as a function of time and temperature, has allowed to determine the formation mechanism. Determination of the pore size distribution of the ware during the firing has revealed that porosity is a crucial property for the oxidation of pyrite. This detailed analysis has finally led to recommendations to limit the formation of CaSO4 during the firing cycle.

The degradation of a paint coating applied to the backs of mirrors was studied using infrared spectroscopy during a standard test. This analytical tool showed that the protective coating is subject to alterations within a thickness ranging from the surface to at least 7.65 μm. The effects of the normalized test lead to the dissolution of the calcium carbonate extenders and to chemical modifications of the paint binder. These phenomena are responsible for the progressive erosion of the paint coating surface and for a weakening of its protective properties. The paint film's degradation lead to random corrosion of the metallic layers that make up the mirror backs. ©

This paper deals with the study of the adsorption of sulfur dioxide on tin dioxide surfaces. First, using the method proposed by Walling, we studied surface acidity in order to show the effects of sulfur dioxide treatment. The results obtained were compared with those of a previous infrared analyses on sulfate formed during SO 2 treatment. At the same time, we also studied the effects of tin dioxide hydration. We demonstrated that sulfur dioxide is adsorbed to form sulfate groups on basic OH groups. This was performed by blocking the acidic and basic sites of the tin dioxide surface via the use of ammonia and boron trifluoride acid, respectively. The analysis of the results obtained have enabled us to propose a reactional mechanism for the formation of sulfate groups and the increase in surface acidity depending on experimental conditions.

In studying tin dioxide-based gas sensors under sulphur dioxide, we have confirmed phenomena at the gas/semi-conductor interface during the first and subsequent detections. According to Lalauze et al. [1] , the tin dioxide gas sensor is modified by the first SO 2 exposure. It appears that modification is due to the adsorption of sulphite and sulphate on the semi-conductor surface. After the first detection, the gas sensor response peaks at 200°C. We have shown that this peak is connected with quantity of SO 2 adsorbed during detection at high temperatures (>200°C), and not low ones. Finally, we propose two mechanisms to explain these results.