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Abstract—Powders and ceramic composite materials in an Al2O3–ZrO2system with a concentration of ZrO2of 20 wt % are obtained. The effect of introduction of chromium oxide and yttrium oxide into Al2O3–ZrO2ceramic materials on the phase composition, porosity, microstructure, and mechanical properties is studied. It is shown that the introduction of chromium oxide leads to the improvement of sintering and mechanical properties of the ceramic. Products with the predefined shape of a corresponding computer model are obtained by 3D printing, and also their multistage thermal treatment is carried out. Densely sintered ceramic materials are obtained at 1550 and 1600°C, the open porosity of which is below 1% and microhardness is up to 1646 ± 50 HV. The samples are characterized by a dense microstructure with the grain size of zirconium dioxide from 400 nm to 2 μm and of aluminum oxide from 800 nm to 3 μm. The thickness of the layer formed during 3D printing shows a positive impact of the addition of Cr2O3on the resolution during 3D printing.

Abstract: In this article, we have studied the influence of Mn2+on the properties (phase composition, porosity, microstructure, three-point bending strength, and microhardness) and sintering of the ZrO2–Al2O3–SiO2composite ceramic materials. The ZrO2–Al2O3–SiO2ceramic powder containing 2.5 wt % Al2O3and 0.5 wt % SiO2with specific area of 24.7 m2/g is synthesized through the coprecipitation method. Three concentrations of Mn2+are considered: 0.25, 0.50, and 0.75 mol %. The introduction of Mn2+leads to a significant increase in mechanical properties. The samples are sintered at 1250 and 1300°C for 2 h. The highest value of strength at three-point bending of 761 ± 36 MPa and microhardness of 9.5 ± 0.5 GPa is demonstrated by the material of the composition ZrO2–Al2O3–SiO2containing 0.75 mol % Mn2+sintered at 1300°С. The crack resistance of this material is 7.0 MPa m1/2. At the same time, the highest values of crack resistance of 9.3 ± 0.5 MPa m1/2are shown by materials of the ZrO2–Al2O3–SiO2composition containing 0.75 mol % Mn2+sintered at 1250°C.

Abstract: The paper is devoted to the creation and investigation of the new cement materials formed the new beryite phase (MgHPO4·3H2O) during the setting processes. A cement liquid based on sodium phosphate solution with addition of sodium hyaluronate polymer is used to increase the viscosity and the surface tension in the system and to increase the cohesion of the final product. The effect of cement liquids based on sodium hyaluronate with various concentrations are studied to estimate the phase composition, setting time, pH value, microstructure, injectivity, and strength properties of cement materials.

Abstract: Using inductively coupled plasma atomic emission spectrometry (ICP-AES) and atomic absorption spectroscopy (AAS), we developed methods that allow express determination of impurity elements (Ag, Cu, Fe, and Zn) with good metrological characteristics in a wide range of concentrations from 0.0005 to 10% in medical materials based on calcium phosphate, without preliminary separation of the matrix and without the use of standard composition samples. The relative standard deviation (Sr) is 0.05–0.005 for the element contents from 1 to 10% and does not exceed 0.15 for the element contents from 0.0005 to 0.1%. New methods of analytical control provided research on the development of composite materials based on substituted calcium phosphate for medical purposes which exhibit antibacterial activity.

Abstract: Cement materials based on calcium sulfate into which up to 20 mol % of phosphate groups were introduced were obtained in order to improve their cytocompatibility and solubility. It was found that, during exposure of cement materials on the basis of calcium sulfate containing 0, 5, 10, and 20 mol% phosphate groups in model Kokubo solution (simulated body fluid (SBF) simulating the composition of human blood plasma) and Dulbecco’s phosphate-buffered saline (DPBS), the formation of a calcium phosphate layer on the surface of the samples was observed in dynamics up to 28 days. In this case, the process of recrystallization of sulfate and phosphate phases was more pronounced in SBF than in DPBS. In in vitro studies on the MG-63 human osteosarcoma line cell culture, cement samples showed cytocompatibility with the presence of moderate matrix surface properties.

Dans la recherche épidémiologique, la précision et validité des diagnostics est primordiale, les questionnaires auto-administrés dépendent fortement du patient et les algorithmes issus du Système national des données de santé (SNDS) de la qualité des codages, introduisant un possible biais et affectant la qualité des diagnostics. Cette étude examine d'une part la concordance des données pour quatre cancers (côlon-rectum, poumon, prostate, sein) entre les auto-questionnaires de la Cohorte Constances et les algorithmes SNDS (cartographie Cnam), et d'autre part la validité de chaque source, peu explorée jusqu’à présent.

Abstract: A wide range of compositions of zirconia-based composites containing 0, 5, 10, 20 wt % alumina was studied. The dependences of the formation of microstructure and phase composition on the sintering temperature were established. It was shown that the introduction of additives forming low-temperature melts based on sodium silicates, Na2SiO3and Na2Si2O5, led to a decrease in sintering temperature by 150–200°C. As a result, dense nanocrystalline materials with a crystal size of 50–200 nm, strength of up to 500 MPa, and sintering temperature of 1300–1400°C were obtained.

Prédire l'évolution de la maladie permettrait d'améliorer la prise en charge des patients et de réduire le fardeau de la maladie. La base de données médico-administratives du SNDS pourrait permettre de construire des modèles prédictifs de l'évolution de la sévérité des maladies et d'orienter des politiques de prise en charge des patients.

Les données sur le fardeau de l'asthme en France sont rares et anciennes. A partir de la cohorte Constances portant sur plus de 200 000 volontaires, l'objectif de l'étude était de décrire le fardeau de l'asthme selon le niveau de traitement GINA en France (comorbidités, consommations de soins et coûts).

Polymorphonuclear neutrophils (PMNs) are the primary leukocytes present in the healthy and inflamed oral cavity. While unique PMN activation states have been shown to differentiate health and periodontitis, little is known about the changes in PMN activation states that occur during the transition from periodontal health to gingivitis. The objective of this study was to characterize oral and circulatory PMNs during induction and resolution of experimental gingivitis. Healthy volunteers were recruited to undergo experimental gingivitis. Clinical assessment of pocket depths, bleeding on probing, gingival index, and plaque index, as well as flow cytometric analysis of CD (cluster of differentiation) activation markers on blood and oral PMNs, was performed weekly. All clinical parameters increased significantly during the induction period and returned to baseline levels during the resolution phase. During the induction phase, while oral PMN counts increased, oral PMN activation state based on surface expression of CD63, CD11b, CD16, and CD14 was diminished compared to those seen in health and during the resolution phase. PMNs in circulation during onset showed increased activation based on CD55, CD63, CD11b, and CD66a. Using clinical parameters and oral PMN counts assessed at day 21, we noted 2 unique disease patterns where one-third of subjects displayed an exaggerated influx of oral PMNs with severe inflammation compared to the majority of the population who experienced a moderate level of inflammation and PMN influx. This supports the notion that PMN influx and severe inflammatory changes during gingivitis could identify subjects at risk for the development of severe gingival inflammation and progression toward destructive periodontitis. This study demonstrates that oral PMN activation states are reduced in gingivitis and suggest that only in periodontitis do PMNs become hyperactivated and tissue damaging.Knowledge Transfer Statement:Our article creates a paradigm for future studies of the evolution of essential oral and circulatory biomarkers to identify individuals at risk to develop periodontitis at an early stage of periodontal disease, which is reversible upon proper oral hygiene practices and dental treatments.

Le Système national d’information inter-régimes de l’assurance maladie (Sniiram) est une base de données particulièrement précieuse pour l’épidémiologie, l’économie de la santé, l’évaluation en santé, la surveillance ou la santé publique. Elle est cependant complexe et nécessite d’importants moyens et compétences pour son utilisation. C’est pourquoi la décision de mettre en place un réseau consacré à une meilleure coordination des travaux sur l’utilisation du Sniiram a été prise. L’objectif général du réseau REDSIAM est de favoriser par le partage d’expérience et l’interaction entre équipes le développement, la validation et la promotion des méthodes d’analyse des données médico-administratives à des fins de recherche, de surveillance, d’évaluation et de santé publique. Il est consacré au partage d’expérience, à la mutualisation et la capitalisation des connaissances dans le champ de l’identification des pathologies. Les activités du réseau concernent le développement et la validation des qualités métrologiques d’algorithmes spécifiques de pathologies à partir des données du Sniiram. Sa gouvernance comprend un comité directeur composé de représentants des principaux organismes producteurs et/ou utilisateurs de données du Sniiram, un bureau et un comité technique. Le réseau est organisé en groupes de travail thématiques par domaines pathologiques. Son fonctionnement est défini par une charte qui fixe les règles de participation au réseau, de fonctionnement des groupes de travail thématiques, les règles de publication et de mise à disposition des algorithmes. Les articles qui composent ce numéro spécial de la RESPprésentent les premiers résultats de certains des groupes de travail thématiques.

Parmi les méthodes d’évaluation des risques de TMS, et pour quantifier les expositions biomécaniques en lien avec le travail, l’observation par un expert et/ou des enregistrements en temps réel peuvent être considérés comme des méthodes de référence ; interroger les personnes concernées sur leurs expositions présentes ou passées est aussi classiquement utilisé. Ces dernières années, des Matrices Emplois-Expositions (MEX, ou JEM comme Job Exposure Matrix) ont aussi été développées pour évaluer les expositions biomécaniques. L’objectif de cette présentation est de faire connaître et de discuter les possibilités apportées par les MEX, à partir de la littérature scientifique existante et des projets en cours :

La vitesse de marche (VM) est un marqueur de santé et l'un des critères de fragilité chez les personnes âgées. Simple à mesurer et reproductible, elle est aujourd'hui couramment utilisée en recherche et clinique. Il n'existe pas de normes françaises de VM or elles permettraient l'identification précoce d'individus avec de moins bonnes performances motrices, permettant la mise en place d'un suivi adapté et de mesures de prévention. Notre objectif est d’établir des normes de VM représentatives de la population française affiliée au Régime général (sens large) de la Sécurité Sociale âgée de 45-69 ans.

The objective of this clinical trial was to evaluate the long-term effect of endothelin receptor antagonism with bosentan on the morbidity and mortality of patients with severe chronic heart failure.

Background:While many studies have shown associations between obesity and increased risk of morbidity and mortality, little comparable information is available on how body mass index (BMI) impacts health expectancy. We examined associations of BMI with healthy and chronic disease-free life expectancy in four European cohort studies.Methods:Data were drawn from repeated waves of cohort studies in England, Finland, France and Sweden. BMI was categorized into four groups from normal weight (18.5–24.9 kg m−2) to obesity class II (⩾35 kg m−2). Health expectancy was estimated with two health indicators: sub-optimal self-rated health and having a chronic disease (cardiovascular disease, cancer, respiratory disease and diabetes). Multistate life table models were used to estimate sex-specific healthy life expectancy and chronic disease-free life expectancy from ages 50 to 75 years for each BMI category.Results:The proportion of life spent in good perceived health between ages 50 and 75 progressively decreased with increasing BMI from 81% in normal weight men and women to 53% in men and women with class II obesity which corresponds to an average 7-year difference in absolute terms. The proportion of life between ages 50 and 75 years without chronic diseases decreased from 62 and 65% in normal weight men and women and to 29 and 36% in men and women with class II obesity, respectively. This corresponds to an average 9 more years without chronic diseases in normal weight men and 7 more years in normal weight women between ages 50 and 75 years compared to class II obese men and women. No consistent differences were observed between cohorts.Conclusions:Excess BMI is associated with substantially shorter healthy and chronic disease-free life expectancy, suggesting that tackling obesity would increase years lived in good health in populations.

ObjectivesOccupational exposure to disinfectants is associated with work-related asthma, especially in healthcare workers. However, little is known about the specific products involved. To evaluate disinfectant exposures, we designed job-exposure (JEM) and job-task-exposure (JTEM) matrices, which are thought to be less prone to differential misclassification bias than self-reported exposure. We then compared the three assessment methods: self-reported exposure, JEM and JTEM.MethodsDisinfectant use was assessed by an occupational questionnaire in 9073 US female registered nurses without asthma, aged 49–68 years, drawn from the Nurses' Health Study II. A JEM was created based on self-reported frequency of use (1–3, 4–7 days/week) of 7 disinfectants and sprays in 8 nursing jobs. We then created a JTEM combining jobs and disinfection tasks to further reduce misclassification. Exposure was evaluated in 3 classes (low, medium, high) using product-specific cut-offs (eg, <30%, 30–49.9%, ≥50%, respectively, for alcohol); the cut-offs were defined from the distribution of self-reported exposure per job/task.ResultsThe most frequently reported disinfectants were alcohol (weekly use: 39%), bleach (22%) and sprays (20%). More nurses were classified as highly exposed by JTEM (alcohol 41%, sprays 41%, bleach 34%) than by JEM (21%, 30%, 26%, respectively). Agreement between JEM and JTEM was fair-to-moderate (κ 0.3–0.5) for most disinfectants. JEM and JTEM exposure estimates were heterogeneous in most nursing jobs, except in emergency room and education/administration.ConclusionsThe JTEM may provide more accurate estimates than the JEM, especially for nursing jobs with heterogeneous tasks. Use of the JTEM is likely to reduce exposure misclassification.

Effect of ripening in the mother liquor on the degree of crystallinity and dispersity of mixed powders of calcium and magnesium phosphates is studied as a function of magnesium content with the elemental composition such that (Ca + Mg)/P = 2. Ripening is found to have a positive effect on crystallinity of the apatite phase of powders. Nanocrystals with lowered tendency to aggregation are formed during the ripening period, which affords the powders with specific surface area as high as 80 m2/g. The morphology of the constituent particles depends on the magnesium content. Crystallization processes are essentially completed by the 21st day of ripening.

Les données sur le fardeau de l’asthme en France sont rares et anciennes. À partir de la cohorte Constances portant sur plus de 200 000 volontaires, l’objectif de l’étude était de décrire le fardeau de l’asthme selon le niveau de traitement GINA en France (comorbidités, consommations de soins et coûts).

Le Système national d’information inter-régimes de l’assurance maladie (SNIIRAM) comporte des données d’hospitalisation et de consommation de soins concernant plus de 60 millions de personnes. Bien qu’elles n’informent pas sur de nombreuses données personnelles et environnementales, les données du SNIIRAM ont un intérêt majeur pour l’épidémiologie, la surveillance et la santé publique. Une de ses utilisations particulièrement intéressante est l’appariement avec des données d’enquêtes recueillant des informations directement auprès des personnes. D’accès encore relativement restreint, son ouverture va être largement facilitée par les prochaines évolutions législatives, réglementaires et organisationnelles. Son utilisation nécessite cependant un important travail technique et méthodologique, de contrôle et de validation, du fait qu’il s’agit d’une base de données gigantesque et d’une très grande complexité, qui concerne trois aspects principaux : la volumétrie, l’architecture des données et l’interprétation de celles-ci.

A thermohydrolysis process is considered for aluminum chloride hexahydrate as one of repartition stages for a hydrochloric acid technology of alumina production from Russian high-silicon raw materials. A physicochemical study is performed for the burning of AlCl3· 6H2O, and the temperature ranges for the removal of water and chloride ions are determined. It is shown that chloride ion is released mainly as HCl. The effect of burning temperature on the phase composition and the basic physical properties of the alumina powder (specific surface area, porosity, and average particle size) is studied. The results of optical and electron microscopy showed that the alumina particles retain the hexagonal structure of the source of aluminum chloride hexahydrate. It is established that ultrasonic treatment affects the dispersion level of the aluminum oxide powder. The data obtained allow one to produce metallurgical alumina of “sandy” type which can be used to prepare aluminum metal by means of electrolysis.

Composites in the MoSi2+ Si3N4system containing 1.0, 2.5, and 5.0 wt % Si3N4were synthesized by hot pressing at the temperature of 1650°C and the pressure of 30 MPa. Silicon nitride powders of two types of were used as reinforcing additives: one with isometric equiaxed crystals and one with fibrous structure. The samples were characterized by microstructural and phase analyses; the relative density and the flexural strength were determined. Composites with the flexural strength of up to 410 MPa were synthesized. The resistance to low-temperature oxidation of MoSi2+ Si3N4composites in air at the temperature of 750°C was studied. The increase in the resistance to oxidation of composites with silicon nitride in air compared to pure molybdenum disilicide for both types of silicon nitride powders was established. For all the composites obtained, the parabolic oxidation rate constants were calculated.

The influence of the size and number of calcium carbonate granules introduced to the cement matrix of an alpha-tribasic calcium phosphate–orthophosphoric acid solution on the compression strength of the composite material was studied. A potential increase in strength by a factor of six by the introduction of an optimal amount of granules into the matrix was determined.

Examiner l'association prospective entre la consommation de tabac, d'alcool et de cannabis et l'obtention d'un emploi chez les demandeurs d'emploi.

Nanoscale and microscale surface layers of Ta, Ti, Cu, and Sn on flat and wire NiTi, Cu, Ti, and SiO2substrates were produced by vacuum magnetron sputtering. The structure and the composition of samples were determined by SEM, AES, Auger spectroscopy, and X-ray diffractometry. The thickness and the structure of surface layers were affected by the sputtering distance and power and the bias voltage at the substrate.

The dependence of the sintering of zirconium dioxide on the aluminum oxide content and the use of additives forming the liquid phase during sintering is studied. Dense nanostructured ceramic materials based on zirconium dioxide containing aluminum oxide are synthesized. It is shown that the use of additives based on sodium silicate contributes to the sintering and the formation of a nonporous structure at 1330°C. It is revealed that aluminum oxide in the amount of 1 and 5 wt % increases the density of materials, while at the content of 16 wt % the sintering until the dense state does not occur even at temperatures up to 1550°C.

Bien que la sévérité de la rhinite ait des impacts non-négligeables sur la qualité de vie des patients, aucune étude n’a décrit la rhinite suivant l’intensité de sa sévérité en population générale française. Notre objectif était de décrire les caractéristiques de la rhinite selon le score de sévérité construit sur la base de quatre de ses principaux symptômes parmi les adultes de l’étude épidémiologique en population générale Constances.

Les données sur les consommations de soins et les coûts de l’asthme dans la population française sont rares et anciennes. La cohorte Constances est une cohorte prospective en population portant sur plus de 200 000 volontaires bénéficiant d’un bilan de santé standardisé. L’objectif de cette étude était, à partir de cette cohorte, de décrire l’impact de l’asthme en France en termes de comorbidités, de consommations de soins et de coûts.

Prédire l’évolution de la maladie permettrait d'améliorer la prise en charge des patients et de réduire le fardeau de la maladie. La base de données médico-administratives du SNDS pourrait permettre de construire des modèles prédictifs de l’évolution de la sévérité des maladies et d'orienter des politiques de prise en charge des patients.

A study was carried out on effect of the conditions of physicochemical conversion of a porous gypsum intermediate product to calcium phosphates. Depending on the initial conditions of sample preparation, the materials around hydroxyapatite and dicalcium phosphate were obtained. The conducted thermal analysis and dilatometric studies made it possible to propose the conditions of thermal treatment preventing shrinkage and deformation of samples. After thermal treatment at 1000°C, fine crystalline porous materials were obtained with crystal size between 0.5 and 2 μm and pore size up to 50 μm on the basis of β-tricalcium phosphate with strength up to 2.8 MPa. The developed pore structure and fairly high strength make it possible to use the developed materials based on tricalcium phosphate to obtain biomaterials for the replacement of defects in bone tissue.

Chronic occupational solvent exposure is associated with long-term cognitive deficits. Cognitive reserve may protect solvent-exposed workers from cognitive impairment. We tested whether the association between chronic solvent exposure and cognition varied by educational attainment, a proxy for cognitive reserve.

Research on bone and teeth mineralization in animal models is critical for understanding human pathologies. Genetically modified mice represent highly valuable models for the study of osteo/dentinogenesis defects and osteoporosis. Current investigations on mice dental and skeletal phenotype use destructive and time consuming methods such as histology and scanning microscopy. Micro-CT imaging is quicker and provides high resolution qualitative phenotypic description. However reliable quantification of mineralization processes in mouse bone and teeth are still lacking. We have established novel CT imaging-based software for accurate qualitative and quantitative analysis of mouse mandibular bone and molars. Data were obtained from mandibles of mice lacking the Fibromodulin gene which is involved in mineralization processes. Mandibles were imaged with a micro-CT originally devoted to industrial applications (Viscom, X8060 NDT). 3D advanced visualization was performed using the VoxBox software (UsefulProgress) with ray casting algorithms. Comparison between control and defective mice mandibles was made by applying the same transfer function for each 3D data, thus allowing to detect shape, colour and density discrepencies. The 2D images of transverse slices of mandible and teeth were similar and even more accurate than those obtained with scanning electron microscopy. Image processing of the molars allowed the 3D reconstruction of the pulp chamber, providing a unique tool for the quantitative evaluation of dentinogenesis. This new method is highly powerful for the study of oro-facial mineralizations defects in mice models, complementary and even competitive to current histological and scanning microscopy appoaches.

Our previous work characterizing the biogenesis and structural integrity of the nuclear envelope and nuclear pore complexes (NPCs) has been based on amphibian material but has recently progressed into the analysis of tissue-culture cells. This protocol describes methods for the high resolution visualization, by field-emission scanning electron microscopy (FESEM), of the nucleus and associated structures in tissue culture cells. Imaging by fluorescence light microscopy shows general nuclear and NPC information at a resolution of approximately 200 nm, in contrast to the 3–5 nm resolution provided by FESEM or transmission electron microscopy (TEM), which generates detail at the macromolecular level. The protocols described here are applicable to all tissue culture cell lines tested to date (HeLa, A6, DLD, XTC and NIH 3T3). The processed cells can be stored long term under vacuum. The protocol can be completed in 5 d, including 3 d for cell growth, 1 d for processing and 1 d for imaging.

This protocol details methods for the generation of cell-free extracts and DNA templates from the eggs and sperm chromatin, respectively, of the clawed toad Xenopus laevis. We have used this system with scanning electron microscopy (SEM), as detailed herein, to analyze the biochemical requirements and structural pathways for the biogenesis of eukaryotic nuclear envelopes (NEs) and nuclear pore complexes (NPCs). This protocol requires access to female frogs, which are induced to lay eggs, and a male frog, which is killed for preparation of the sperm chromatin. Egg extracts should be prepared in 1 d and can be stored for many months at −80 °C. Demembranated sperm chromatin should take only approximately 2–3 h to prepare and can be stored at −80 °C almost indefinitely. The time required for assembly of structurally and functionally competent nuclei in vitro depends largely on the quality of the cell-free extracts and, therefore, must be determined for each extract preparation.

This protocol details methods for the isolation of oocyte nuclear envelopes (NEs) from the African clawed toad Xenopus laevis, immunogold labeling of component proteins and subsequent visualization by field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). This procedure involves the initial removal of the ovaries from mature female X. laevis, the dissection of individual oocytes, then the manual isolation of the giant nucleus and subsequent preparation for high-resolution visualization. Unlike light microscopy, and its derivative technologies, electron microscopy enables 3–5 nm resolution of nuclear structures, thereby giving unrivalled opportunities for investigation and immunological characterization in situ of nuclear structures and their structural associations. There are a number of stages where samples can be stored, although we recommend that this protocol take no longer than 2 d. Samples processed for FESEM can be stored for weeks under vacuum, allowing considerable time for image acquisition.

Le syndrome d’interruption de la tige pituitaire (SITP) est défini morphologiquement par une tige pituitaire fine ou absente, une posthypophyse ectopique et/ou une antéhypophyse hypoplasique ou absente. L’objectif est de décrire le développement pubertaire, la fertilité et l’évolution de la fonction gonadotrope de femmes adultes atteintes d’un SITP.