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Global malalignment in adolescent idiopathic scoliosis: The axial deformity is the main driver
No full textInternational audiencePurpose: To evaluate the global alignment of non-operated subjects with adolescent idiopathic scoliosis.Method: A total of 254 subjects with AIS and 64 controls underwent low dose biplanar X-rays and had their spine, pelvis, and rib cage reconstructed in 3D. Global alignment was measured in the sagittal and frontal planes by calculating the OD-HA angle (between C2 dens to hip axis with the vertical). Subjects with AIS were classified as malaligned if the OD-HA was > 95th percentile relative to controls.Results: The sagittal OD-HA in AIS remained within the normal ranges. In the frontal plane, 182 AIS were normally aligned (Group 1, OD-HA = 0.9°) but 72 were malaligned (Group 2, OD-HA = 2.9°). Group 2 had a more severe spinal deformity in the frontal and horizontal planes compared to Group 1 (Cobb: 42 ± 16° vs. 30 ± 18°; apical vertebral rotation AVR: 19 ± 10° vs. 12 ± 7°, all p < 0.05). Group 2 subjects were mainly classified as Lenke 5 or 6. 19/72 malaligned subjects had a mild deformity (Cobb < 30°) but a progressive scoliosis (severity index ≥ 0.6). The frontal OD-HA angle was found to be mainly determined (adjusted-R2 = 0.22) by the apical vertebral rotation and secondarily by the Lenke type.Conclusions: This study showed that frontal malalignment is more common in distal major structural scoliosis and its main driver is the apical vertebral rotation. This highlights the importance of monitoring the axial plane deformity in order to avoid worsening of the frontal global alignment
Physical limitations induced by a wheat bran-based medium for the production of biopesticides by Bacillus thuringiensis serovar kurstaki
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Optimal sizing and real-time EMS for low carbon emissions of a hybrid islanded microgrid
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Caractérisation des phtalates dans l’atmosphère urbaine de deux sites Est-Méditerranéens
No full textInternational audienceL'incinération sauvage des déchets ménagers libère dans l’atmosphère des polluants gazeux et particulaires nocifs à la santé humaine. Parmi ces polluants, on retrouve les phtalates qui sont présents dans les matières plastiques et peuvent être libérés dans l’air ambiant. Différentes études ont montré que les phtalates sont des perturbateurs endocriniens et peuvent également affecter la santé reproductive et l’intelligence chez les enfants.L’objectif de ce travail est d’étudier les niveaux de concentrations des phtalates dans des échantillons journaliers de particules fines (PM2.5) entre décembre 2018 et octobre 2019 sur deux sites Est-Méditerranéens localisés au Liban : Zouk Mikael (ZK) et Fiaa (FA). Le site de Zouk Mikael abrite la plus grande centrale thermique du pays et utilise comme combustible du fioul lourd. Le site de Fiaa, dans la région de Chekka, est un site plus rural et sous l’influence des émissions des cimenteries et leurs carrières. La composition des PM2.5 a été déterminée en insistant sur les fractions carbonée et organique, les ions hydrosolubles ainsi que les éléments majeurs et traces. La caractérisation de la fraction organique inclue l’étude de composés primaires comme les phtalates et plus spécifiquement le diisobutylphtalate (DIBP), le dibutylphtalate (DBP) et le bis(2-ethylhexyl)phtalate (DEHP), mais aussi les hydrocarbures aromatiques polycycliques (HAP), les alcanes, les acides gras, les hopanes,… Ces composés, quantifiés pour la première fois au Liban, ont montré des concentrations moyennes élevées sur les deux sites (107 ng/m3 à ZK et 98 ng/m3 à FA). Le bis(2-ethylhexyl)phtalate présente les concentrations les plus élevées parmi les 3 espèces. De plus, une attention particulière a été portée aux corrélations entre le DIBP et le DnBP. Les résultats montrent que, sur le site de FA, ces composés sont majoritairement émis de l’incinération non contrôlée des déchets sur toute la période d’échantillonnage. Sur le site de ZK, l'étude du ratio de concentration DIBP/DnBP, suggère pour la période allant de mai à décembre 2019 une source supplémentaire comparé au site de FA
Human health risk assessment for PAHs, phthalates, elements, PCDD/Fs, and DL-PCBs in PM2.5 and for NMVOCs in two East-Mediterranean urban sites under industrial influence
No full textInternational audienceThis study evaluates the carcinogenic and the non-carcinogenic health risks related to non-methane volatile organic compounds (NMVOCs) and elements, dioxins, furans, dioxin-like polychlorobiphenyls, phthalates and polycyclic aromatic hydrocarbons in PM 2.5 samples collected during a one-year field campaign in two urban industrial areas in the East Mediterranean region. The health risk was assessed for the three exposure pathways (ingestion, inhalation and dermal contact) and for different age categories (newborns, children, adolescents, and adults). The non-carcinogenic risk calculated for the different species showed that benzene and n-heptane explained 78-94% of the total hazard index (HI) for NMVOCs at both sites. The total HI for NMVOCs varied between 2.9 and 26.8 at Zouk and between 0.8 and 6.6 at Fiaa for adults and newborns respectively exceeding the recommended USEPA limit of 1 for most age categories. PM 2.5-bound elements had values higher than the recommended USEPA limit for newborns with Mn, Pb, V, and Ni as the major contributors. The other species under study presented moderate risk values. The lifetime cancer risk due only to the exposure to NMVOCs was 170 and 46 times higher than the threshold limit at Zouk and Fiaa, respectively. PM 2.5-bound PAHs, As, Co, Cr (VI), Ni and V concentrations showed lifetime cancer risk exceeding the threshold limit of 10 − 6 with 58 and 28 additional cancer cases per million habitats at Zouk and Fiaa, respectively. To our knowledge, this assessment is a first evaluating the health risk of several classes of compounds from both particulate and gas phases
Characterization of the epithelial responses triggered by Bacillus thuringiensis oral infections in Drosophila
No full textInternational audienceAmong biopesticides, Bacillus thuringiensis (Bt) is the most widely used in agriculture for the control of insect pests and vectors. Bt is a Gram-positive endospore-forming bacterium that produces a wide range of toxins with specific biological targets. Bt strains differ by the production of diverse -endotoxins cocktails, which define potential target hosts. These findings have long motivated the isolation and characterization of new Bt strains for the use as biocontrol agents. However, the inadvertent effects of these bacteria on non-target organisms remain largely unexplored. In this study, we have developed an oral infection model to investigate the putative effects of different Bt strains on Drosophila melanogaster as a non-target host. Taking advantage of the powerful molecular and genetic tools of this model organism, we explore the epithelial reactions triggered upon the ingestion of Bt spores and the relative contribution of epithelial defenses in the fight against the infections. Our data emphasize a toxin-dependent epithelial induced response and highlights the major contribution of the epithelial arm of defense in the control of Bt oral infections
Methods for the assessment of health risk induced by contaminants in atmospheric particulate matter: a review
No full textInternational audienceAir pollution is a major issue for human health with more than 7 million premature deaths per year due to indoor and outdoor air pollution. Exposure to particulate matter is correlated with adverse health effects in the short and long run. Evaluating the health risk from exposure to particulate matter is challenging because particulate matter contains many contaminants and observed diseases result from multiple causes. Here we review advanced methods for the evaluation of cancer and non-cancer risks induced by exposure to contaminants in particulate matter. Contaminants include polycyclic aromatic hydrocarbons, phthalates, dioxins, furans, dioxin-like polychlorobiphenyls, and major and trace elements. We discuss risk assessment by ingestion, inhalation, and dermal contact, and for population age categories. We observe that the highest contributions to cancer risk come from benzo[a]pyrene, indeno[1,2,3-c,d]pyrene, benzo[k]fluoranthene, dibenz[a,h]anthracene, chromium, arsenic, cadmium, and cobalt
The Assessment of Quality of the Root Canal Filling and the Number of Visits Needed for Completing Primary Root Canal Treatment by Operators with Different Experience
No full textThe main goal of root canal treatment (RCT) is to eradicate or essentially diminish the microbial population within the root canal system and to prevent reinfection by a proper chemo-mechanical preparation and hermetic final obturation of the root canal space. The aim of this study was to assess the quality of the root canal filling and the number of visits needed for completing RCT by operators with different experience, including dentistry students (4th and 5th year), general dental practitioners (GDPs), and endodontists. Data from medical records of 798 patients were analyzed, obtaining 900 teeth and 1773 obturated canals according to the inclusion and exclusion criteria. A similar number of teeth was assessed in each group in terms of density and length of root canal filling and number of visits. The larger number of visits and the lower quality of treatment was observed for 4th year students than for other groups (p < 0.05); in contrast, the endodontists needed the lowest number of visits to complete RCT and more often overfilled teeth than other operator groups (p < 0.05). Interestingly, no statistical difference in quality of root canal filling was noted between 5th year students, GPDs and endodontists. The treatment of lower teeth demanded statistically more visits than that of upper teeth (p < 0.05). The results of the study emphasize that most of the root canal filling performed by operators was considered adequate, regardless of tooth type, files used and number of visits. Keywords: endodontists; general practicing dentists; root canal treatment; quality; undergraduate student
Euclid: Forecasts from redshift-space distortions and the Alcock-Paczynski test with cosmic voids
No full text15 pages, 7 figures. Accepted in A&AInternational audienceEuclid will survey galaxies in a cosmological volume of unprecedented size, providing observations of more than a billion objects distributed over a third of the full sky. Approximately 20 million of these galaxies will have spectroscopy available, allowing us to map the three-dimensional large-scale structure of the Universe in great detail. This paper investigates prospects for the detection of cosmic voids therein, and the unique benefit they provide for cosmology. In particular, we study the imprints of dynamic and geometric distortions of average void shapes and their constraining power on the growth of structure and cosmological distance ratios. To this end, we make use of the Flagship mock catalog, a state-of-the-art simulation of the data expected to be observed with Euclid. We arrange the data into four adjacent redshift bins, each of which contains about 11000 voids, and estimate the void-galaxy cross-correlation function in every bin. Fitting a linear-theory model to the data, we obtain constraints on and , where is the linear growth rate of density fluctuations, the galaxy bias, the comoving angular diameter distance, and the Hubble rate. In addition, we marginalize over two nuisance parameters included in our model to account for unknown systematic effects in the analysis. With this approach Euclid will be able to reach a relative precision of about 4% on measurements of and 0.5% on in each redshift bin. Better modeling or calibration of the nuisance parameters may further increase this precision to 1% and 0.4%, respectively. Our results show that the exploitation of cosmic voids in Euclid will provide competitive constraints on cosmology even as a stand-alone probe. For example, the equation-of-state parameter for dark energy will be measured with a precision of about 10%, consistent with earlier more approximate forecasts
Impacts of Resveratrol and Pyrogallol on Physicochemical, Mechanical and Biological Properties of Epoxy-Resin Sealers
No full textThis study aimed at evaluating the physicochemical and biological properties of experimen- tal epoxy-resin sealers containing polyphenols such as resveratrol and pyrogallol. A conventional epoxy resin (OB) was modified by adding different concentrations of resveratrol (RS) or pyrogallol (PY) to its composition. Antibacterial and antioxidant activities, mechanical properties, along with wettability and morphological changes were investigated. The results were statistically analyzed using ANOVA and multiple comparison tests (α = 0.05). The incorporation of the tested polyphenols into the epoxy resin enhanced its mechanical properties. PY demonstrated much better antioxidant and antibacterial activities than RS, which were associated with a higher release of PY. In contrast, PY showed a higher cytotoxicity than OB and OB doped with RS. OB containing PY presented a rougher surface and higher water absorption than OB doped with RS. Both tested polyphenols caused no notable changes to the overall porosity of OB. Resveratrol and pyrogallol may not only influence the morphology and mechanical properties of epoxy-resin sealers, but could also enhance antioxidant activity and antibacterial effects against Enterococcus faecalis. Most epoxy-resin sealers currently avail- able in the market can be considered as “passive” materials. Thus, doping their composition with specific polyphenols may be a suitable strategy to confer some antibacterial properties, antioxidant potential, along with improvement of some mechanical properties. Keywords: endodontic sealer; polyphenols; resveratrol; pyrogallol; biological activit