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

Compensation of Beer-Lambert attenuation using non-diffracting Bessel beams

We report on a versatile method to compensate the linear attenuation in a medium, independently of its microscopic origin. The method exploits diffraction-limited Bessel beams and tailored on-axis intensity profiles which are generated using a phase-only spatial light modulator. This technique for compensating one of the most fundamental limiting processes in linear optics is shown to be efficient for a wide range of experimental conditions (modifying the refractive index and the attenuation coefficient). Finally, we explain how this method can be advantageously exploited in applications ranging from bio-imaging light sheet microscopy to quantum memories for future quantum communication networks

Abnormal small heat shock protein interactions involving neuropathy-associated HSP22 (HSPB8) mutants

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154632/1/fsb2fj065911fje.pd

Selective separation and preconcentration of Th(IV) using organo-functionalized, hierarchically porous silica monoliths

The potential application of thorium (Th) as nuclear fuel, as well as the environmental and public health concerns associated with it, promotes the development of economic and sustainable materials for the separation and removal of Th(IV) from minerals and environmental samples. In this work, centimeter-size, porous silica monoliths exhibiting hierarchical macroporosity-mesoporosity -and a robust silica skeleton were prepared using a sol−gel process combined with post-synthetic hydrothermal treatment in ammonium hydroxide. Upon functionalization with diglycolamide (DGA), the monolithic silica was used as a column-type fixed bed sorbent for continuous flow extraction. An enhanced Th(IV) uptake from aqueous solution was achieved with high enrichment factor and selectivity in the presence of competitive ions such as rare earth elements (REEs) and uranium (U). Systematic mechanistic studies show that the hierarchical pore system is crucial for enhanced adsorption kinetics and capacity. Two mineral leachates were used to assess the performances of the hybrid material, and despite the complex ion matrix and high ionic composition, the sorbent shows highly efficient recovery of Th(IV). The material was able to undergo 10 extraction-stripping-regeneration cycles, which bode well for potential industrial applications

Polar cap arcs from the magnetosphere to the ionosphere: kinetic modelling and observations by Cluster and TIMED

On 1 April 2004 the GUVI imager onboard the TIMED spacecraft spots an isolated and elongated polar cap arc. About 20 min later, the Cluster satellites detect an isolated upflowing ion beam above the polar cap. Cluster observations show that the ions are accelerated upward by a quasi-stationary electric field. The field-aligned potential drop is estimated to about 700 V and the upflowing ions are accompanied by a tenuous population of isotropic protons with a temperature of about 500 eV. <br><br> The magnetic footpoints of the ion outflows observed by Cluster are situated in the prolongation of the polar cap arc observed by TIMED GUVI. The upflowing ion beam and the polar cap arc may be different signatures of the same phenomenon, as suggested by a recent statistical study of polar cap ion beams using Cluster data. <br><br> We use Cluster observations at high altitude as input to a quasi-stationary magnetosphere-ionosphere (MI) coupling model. Using a Knight-type current-voltage relationship and the current continuity at the topside ionosphere, the model computes the energy spectrum of precipitating electrons at the top of the ionosphere corresponding to the generator electric field observed by Cluster. The MI coupling model provides a field-aligned potential drop in agreement with Cluster observations of upflowing ions and a spatial scale of the polar cap arc consistent with the optical observations by TIMED. The computed energy spectrum of the precipitating electrons is used as input to the Trans4 ionospheric transport code. This 1-D model, based on Boltzmann's kinetic formalism, takes into account ionospheric processes such as photoionization and electron/proton precipitation, and computes the optical and UV emissions due to precipitating electrons. The emission rates provided by the Trans4 code are compared to the optical observations by TIMED. They are similar in size and intensity. Data and modelling results are consistent with the scenario of quasi-static acceleration of electrons that generate a polar cap arc as they precipitate in the ionosphere. The detailed observations of the acceleration region by Cluster and the large scale image of the polar cap arc provided by TIMED are two different features of the same phenomenon. Combined together, they bring new light on the configuration of the high-latitude magnetosphere during prolonged periods of Northward IMF. Possible implications of the modelling results for optical observations of polar cap arcs are also discussed

Effects of Single-Gender and Coeducational Learning Environments on Middle School Mathematics Achievement

As a result of the increased number of schools failing to meet adequate yearly progress (AYP), school districts are searching for innovative ways to raise student achievement and meet the rigorous performance standards set by state governments. Using the theoretical framework provided by brain research and the theory of multiple intelligences, the purpose of this quantitative study was to compare 2 middle school classroom structures for differences in mathematics achievement among students. The study examined whether a significant difference existed in mathematics achievement scores on the state-mandated mathematics test for 2 groups (single gender classes versus coeducational classes) in 6 middle schools during a 3-year period. Mean scores from the Palmetto Assessment of State Standards (PASS) performance statistics in mathematics were used to determine achievement levels of single-gender and coeducational instruction. Study results indicated a statistically significant difference in academic performance for students in single-gender mathematics classes compared with academic performance for students in coeducational mathematics classes. Further, girls outperformed boys. These findings led to a project consisting of implementing a professional learning community and a series of professional development sessions for Algebra I teachers. The results of this study may contribute to social change by identifying an academic program structure in which all students can be supported academically while providing teachers with ongoing opportunities to collaborate and build their capacities with the goal of improving student performance

Getting off on the right foot: Integration of spatial distribution of genetic variability for aquaculture development and regulations, the European perch case

International audienceKnowledge of spatial genetic variability patterns allows improving conservation actions, translocation regulations, and farming productivity. However, these genetic variability patterns are often considered after issues are observed, long after the beginning of production. By taking into account lessons from other species, we investigate the genetic variability of Perca fluviatilis, a species at a nascent stage of production. The genetic variability has been previously studied but, due to discrepancies between conclusions and methodological limits, the spatial distribution of genetic variability in P. fluviatilis has not been demonstrated conclusively. Here, we characterise the genetic variability across 84 West-Palaearctic sampling sites using mitochondrial and microsatellite markers. We aim to provide (i) a genetically-based population structure that could act as an impetus for further production improvement and (ii) guidelines for translocation regulations. Our analyses show an uneven distribution of genetic variability. Based on inter-populational genetic differentiation, we identify five large geographic scale clusters which are further divided into several subgroups. Local genetic diversity mapping highlights a spatial pattern with several hotspots, which has serious implications in the development of appropriate regulations of translocations. Moreover, we here report an association between genetic differentiations and previously reported zootechnical performances. We ultimately propose guidelines for further investigations of population-specific performances in aquaculture and potentially efficient regulations for policy-makers