New calcium carbonate-based cements for bone reconstruction

The feasibility of calcium carbonate-based cements involving the re-crystallization of metastable calcium carbonate varieties has been demonstrated. Two cement compositions were obtained by mixing either calcium carbonate phases (cement A) or a calcium carbonate and a calcium phosphate phase (cement B) with an aqueous media. These cements set and hardened after 30 minutes and 90 minutes respectively. The final composition of cement A was calcite and aragonite whereas cement B lead to a carbonated apatite analogous to bone mineral. Despite poor mechanical properties the presence of a high carbonate content in the final phase might be of interest to increase the cement resorption rate and to favour its replacement by bone tissue. First assays of implantation performed on fresh anatomical pieces (fresh cadavers) at 37°C revealed important advantages of such cement compositions: easiness of use, rapid setting, good adhesion to bone, very good homogeneity and stability of the cement

Language and Proofs for Higher-Order SMT (Work in Progress)

Satisfiability modulo theories (SMT) solvers have throughout the years been able to cope with increasingly expressive formulas, from ground logics to full first-order logic modulo theories. Nevertheless, higher-order logic within SMT is still little explored. One main goal of the Matryoshka project, which started in March 2017, is to extend the reasoning capabilities of SMT solvers and other automatic provers beyond first-order logic. In this preliminary report, we report on an extension of the SMT-LIB language, the standard input format of SMT solvers, to handle higher-order constructs. We also discuss how to augment the proof format of the SMT solver veriT to accommodate these new constructs and the solving techniques they require.Comment: In Proceedings PxTP 2017, arXiv:1712.0089

Efficiency of an inexpensive liquid-based cytology performed by cytocentrifugations: a comparative study using the histology as reference standard

BACKGROUND: Although liquid-based cytology (LBC) is now recommended for cervical cancer screening, it requires expensive automated devices and materials. To evaluate the efficiency of inexpensive LBC methods relying on an inexpensive fixative liquid, Easyfix(®), we compared the results obtained by the liquid-based cytology (LBC) diagnoses performed by cytocentrifugations (Papspin(® )and Turbitec(®)) with those obtained by histology. Furthermore, we evaluated the efficiency of the fixative liquid, Easyfix(®), to preserve HPV DNA in the collected samples. METHOD: 266 LBC were compared with 174 colposcopies and 91 Loop Electrosurgical Excision Procedure (LEEP). Among the LBC, 51 were performed using the Papspin(® )system and 215 were performed using the Turbitec(® )system. To control the quality of the preservation liquid, Easyfix(®), we correlated the results of HCII assays with those of HPV PCR. RESULTS: For Papspin(® )and Turbitec(® )systems, the sensitivities were respectively 82.6% (95% CI: 61.2–95.0%, p < 0.001) and 75.0% (95% CI: 64.4–89.8%, p < 0.001) and the specificities were 92.6% (95%CI: 76.5–99.1%, p < 0.001) and 96.2% (95% CI: 91.3–98.7%, p < 0.001). We find no statistical difference between the results of the both systems (p = ns). The sensitivity of the HCII was 86.4% (95% IC: 77.4–92.8%, p < 0.001) and the specificity was 39.4% (95% CI: 31.2–48.1%, p < 0.001). The comparison between HCII and HPV-PCR shows a good correlation: the kappa was 0.89. CONCLUSION: LBC performed by cytocentrifugations are inexpensive, reduce inadequate smears, show excellent efficiency and allow HPV detection by molecular biology

Homogeneous light in shade-house experiment overestimates carbon gains in Norway maple seedlings

We set up a shade-house experiment with Norway maple growing at two light intensities typical of a disturbed and undisturbed forest canopy from either a homogeneous or a dynamic regime that mimics sunflecks. We show that although horticultural-grade shade-cloths can be finely tuned to provide daily averages of any light intensity, they do not appropriately mimic natural forest understories which are characterized by dynamic light environments composed of intense but short direct light events interspaced with prolonged period of low diffuse light. The results suggest that replicating the dynamic light environment of forests could be very important in experiments aimed at identifying the traits responsible for invasiveness in exotic species in forest understories, such as Norway maple in North America

Semi-automated stereoradiographic upper limb 3D reconstructions using a combined parametric and statistical model: a preliminary study

PURPOSE: Quantitative assessment of 3D clinical indices may be crucial for elbow surgery planning. 3D parametric modeling from bi-planar radiographs was successfully proposed for spine and lower limb clinical investigation as an alternative for CT-scan. The aim of this study was to adapt this method to the upper limb with a preliminary validation. METHODS: CT-scan 3D models of humerus, radius and ulna were obtained from 20 cadaveric upper limbs and yielded parametric models made of geometric primitives. Primitives were defined by descriptor parameters (diameters, angles...) and correlations between these descriptors were found. Using these correlations, a semi-automated reconstruction method of humerus using bi-planar radiographs was achieved: a 3D personalized parametric model was built, from which clinical parameters were computed [orientation and projections on bone surface of trochlea sulcus to capitulum (CTS) axis, trochlea sulcus anterior offset and width of distal humeral epiphysis]. This method was evaluated by accuracy compared to CT-scan and reproducibility. RESULTS: Points-to-surface mean distance was 0.9 mm (2 RMS = 2.5 mm). For clinical parameters, mean differences were 0.4-1.9 mm and from 1.7° to 2.3°. All parameters except from angle formed by CTS axis and bi-epicondylar axis in transverse plane were reproducible. Reconstruction time was about 5 min. CONCLUSIONS: The presented method provides access to morphological upper limb parameters with very low level of radiation. Preliminary in vitro validation for humerus showed that it is fast and accurate enough to be used in clinical daily practice as an alternative to CT-scan for total elbow arthroplasty pre operative evaluation

Tractable term-structure models and the zero lower bound

We greatly expand the space of tractable term-structure models. We consider one example that combines positive yields with rich volatility and correlation dynamics. Bond prices are expressed in closed form and estimation is straightforward. We find that the early stages of a recession have distinct effects on yield volatility. Upon entering a recession when yields are far from the lower bound, (i) the volatility term structure becomes flatter, (ii) the level and slope of yields are nearly uncorrelated, and (iii) the second principal component of yields plays a larger role. However, these facts are significantly different when yields are close to the lower bound. Entering a recession in such a setting, (i) the volatility term structure instead steepens, (ii) the level and slope factors are strongly correlated, and (iii) the second principal component of yields plays a smaller role. Existing dynamic term-structure models do not capture the changes in the cyclical responses of the volatility term structure near the lower bound

Major accidents scenarios used for LUP and off-site emergency planning : importance of kinetic description

International audienceThe European States, France in particular, faced with several industrial accidents, like one of the most serious one, the AZF explosion in Toulouse (France) in 2001, which created the trauma of the stakeholders concerned by the chemical risk (industry, authorities and citizen). Learning from this experience, the French Ministry in charge of the Environment, with the help of INERIS, worked on upgrading its chemical risks knowledge and studied to improve new methods on risk assessment. In 2004, INERIS was in charge of developing a new approach to classify accidental scenarios in terms of probability, severity and response time. In this paper, INERIS proposes a prioritisation based on time of occurrence, of development of hazardous phenomena and of effects on targets. Then, INERIS shows a method enabling to integrate, as a second prioritisation criteria, the on-site and off-site response capabilities/abilities as well as the means for population protection in terms of time allowed

Forestry plantations as a pathway for invasive alien plants in the National Park at Réunion island

Identifying pathways of introduction remains a major priority to prevent future plant invasions into natural areas. In this study, we assessed whether forestry plantations favor alien plant dissemination into the National Park of Reunion. Results showed significant decrease in the percentage of alien plant biomass from the forestry plantations to the undisturbed areas. At one site, a significant difference was also found for the mean alien species number and the mean alien plant abundance. In both sites, numerous alien species were present in the understorey of Cryptomeria plantations only, with some already escaping and occurring at the entrance of the National Park. This study recommends strengthening early detection and rapid response of alien plants and suggests alternative management approaches in forestry plantations, including the use of community-based restoration programmes.Une des priorités pour contrôler les futures invasions floristiques est d’identifier les voies d’introduction aux abords des aires naturelles. Dans cette étude, nous avons testé si les forêts cultivées peuvent favoriser l’envahissement par les plantes exotiques à l’intérieur du Parc national de la Réunion. Les résultats montrent une diminution significative du pourcentage de la biomasse végétale des plantes exotiques des forêts cultivées vers le milieu naturel. Les différences sont également significatives au niveau d’un des deux sites étudiés concernant les moyennes du nombre de plantes exotiques et de la somme de l’abondance des plantes. Dans les deux cas, de nombreuses espèces sont présentes seulement en sous-bois de forêts cultivées ou également à l’entrée du Parc national. Cette étude préconise de renforcer les actions de détection précoce et de réponse rapide. Les auteurs proposent également la mise en place de méthodes de gestion alternatives de ces habitats incluant une approche participative de la population dans des programmes de restauration

Forestry plantations as a pathway for invasive alien plants in the National Park at Réunion island

Identifying pathways of introduction remains a major priority to prevent future plant invasions into natural areas. In this study, we assessed whether forestry plantations favor alien plant dissemination into the National Park of Reunion. Results showed significant decrease in the percentage of alien plant biomass from the forestry plantations to the undisturbed areas. At one site, a significant difference was also found for the mean alien species number and the mean alien plant abundance. In both sites, numerous alien species were present in the understorey of Cryptomeria plantations only, with some already escaping and occurring at the entrance of the National Park. This study recommends strengthening early detection and rapid response of alien plants and suggests alternative management approaches in forestry plantations, including the use of community-based restoration programmes.Une des priorités pour contrôler les futures invasions floristiques est d’identifier les voies d’introduction aux abords des aires naturelles. Dans cette étude, nous avons testé si les forêts cultivées peuvent favoriser l’envahissement par les plantes exotiques à l’intérieur du Parc national de la Réunion. Les résultats montrent une diminution significative du pourcentage de la biomasse végétale des plantes exotiques des forêts cultivées vers le milieu naturel. Les différences sont également significatives au niveau d’un des deux sites étudiés concernant les moyennes du nombre de plantes exotiques et de la somme de l’abondance des plantes. Dans les deux cas, de nombreuses espèces sont présentes seulement en sous-bois de forêts cultivées ou également à l’entrée du Parc national. Cette étude préconise de renforcer les actions de détection précoce et de réponse rapide. Les auteurs proposent également la mise en place de méthodes de gestion alternatives de ces habitats incluant une approche participative de la population dans des programmes de restauration