Octacalcium phosphate crystals directly stimulate expression of inducible nitric oxide synthase through p38 and JNK mitogen-activated protein kinases in articular chondrocytes

Basic calcium phosphate (BCP) crystals, including hydroxyapatite, octacalcium phosphate (OCP) and carbonate-apatite, have been associated with severe osteoarthritis and several degenerative arthropathies. Most studies have considered the chondrocyte to be a bystander in the pathogenesis of calcium crystal deposition disease, assuming that synovial cell cytokines were the only triggers of chondrocyte activation. In the present study we identified direct activation of articular chondrocytes by OCP crystals, which are the BCP crystals ith the greatest potential for inducing inflammation. OCP crystals induced nitric oxide (NO) production and inducible nitric oxide synthase (NOS) mRNA expression by isolated articular chondrocytes and cartilage fragments, in a dose-dependent manner and with variations over time. OCP crystals also induced IL-1β mRNA expression. Using pharmacological and cytokine inhibitors, we observed that OCP crystals induced NO production and inducible NOS mRNA activation were regulated at both the transcriptional and the translational levels; were independent from IL-1β gene activation; and involved p38 and c-Jun amino-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) pathways, as further confirmed by OCP crystal-induced p38 and JNK MAPK phosphorylation. Taken together, our data suggest that the transcriptional inducible NOS response to OCP crystals involved both the p38 and the JNK MAPK pathways, probably under the control of activator protein-1. NO, a major mediator of cartilage degradation, can be directly produced by BCP crystals in chondrocytes. Together with synovial activation, this direct mechanism may be important in the pathogenesis of destructive arthropathies triggered by microcrystals

Résilience systémique d’un territoire composé d’activités essentielles suite à une perturbation majeure – Approches systémique et spatiale

Too many dramatic events occurred over the last ten years have demonstrated the severity and extent of impacts that territories may be confronted with. Damages to critical infrastructures may have a variety of downfall disturbing effects, which can lead territories and society into a huge crisis. Interdependency between these essential activities on the one hand, and between these activities and the population on the other hand, increases their vulnerability. This thesis presents a methodology to better assess direct and indirect impacts of a major disturbance. The issue is addressed from a multi-activity perspective, to take into account territories complexity.In the first stage, a territory is modeled using existing interdependency links between essential activities and the population. The methodology then identifies, based on a defined initial event, possible propagation scenarios and their consequences on services “users”. Finally, this simulation gives an assessment of the territory stakes resilience. This works provides a decision-making tool for the development of activity continuity plans, or risk assessment and mitigation policies.De trop nombreux évènements survenus la décennie passée illustrent la gravité et l’étendue des impacts auxquels les territoires peuvent être confrontés. L'atteinte aux infrastructures critiques peut induire de très nombreux dysfonctionnements en cascade pouvant plonger ce territoire et sa société dans une crise de grande ampleur. Les interdépendances entre ces activités essentielles et celles avec la population accentuent leur fragilité. Afin d'évaluer les impacts directs et indirects d'une perturbation majeure, la méthodologie développée étudie la problématique sous un angle multisectoriel répondant ainsi à une prise en compte de la complexité des territoires. Dans un premier temps, le territoire via ses activités essentielles et sa population est modélisé en s'appuyant sur les liens d'interdépendance existants. Sur la base d'un évènement initial donné, la méthode identifie les scénarios de propagation possibles et leurs conséquences sur les "usagers" concernés par la délivrance des services touchés. Cette simulation permet ainsi d'apprécier la résilience systémique des enjeux du territoire. Basé sur une approche systémique et spatiale, ce travail a pour objectif de fournir une aide à la décision à la planification des mesures de continuité et de rétablissement d'activité ou à la mise en place de mesures de traitement des risques

Artificial Neural Network (ANN) in a Small Dataset to determine Neutrality in the Pronunciation of English as a Foreign Language in Filipino Call Center Agents

Artificial Neural Networks (ANNs) have continued to be efficient models in solving classification problems. In this paper, we explore the use of an ANN with a small dataset to accurately classify whether Filipino call center agents’ pronunciations are neutral or not based on their employer’s standards. Isolated utterances of the ten most commonly used words in the call center were recorded from eleven agents creating a dataset of 110 utterances. Two learning specialists were consulted to establish ground truths and Cohen’s Kappa was computed as 0.82, validating the reliability of the dataset. The first thirteen Mel-Frequency Cepstral Coefficients (MFCCs) were then extracted from each word and an ANN was trained with Ten-fold Stratified Cross Validation. Experimental results on the model recorded a classification accuracy of 89.60% supported by an overall F-Score of 0.92

Integrated spatial multiplexing of heralded single photon sources

The non-deterministic nature of photon sources is a key limitation for single photon quantum processors. Spatial multiplexing overcomes this by enhancing the heralded single photon yield without enhancing the output noise. Here the intrinsic statistical limit of an individual source is surpassed by spatially multiplexing two monolithic silicon correlated photon pair sources, demonstrating a 62.4% increase in the heralded single photon output without an increase in unwanted multi-pair generation. We further demonstrate the scalability of this scheme by multiplexing photons generated in two waveguides pumped via an integrated coupler with a 63.1% increase in the heralded photon rate. This demonstration paves the way for a scalable architecture for multiplexing many photon sources in a compact integrated platform and achieving efficient two photon interference, required at the core of optical quantum computing and quantum communication protocols.Comment: 10 pages, 3 figures, comments welcom

Technical validation and a comparison of two methods to quantify individual levels of glucocorticoids in Alpine marmot hair

Quantification of cortisol concentration in hair has become a promising conservation tool for non-invasive monitoring of “stress” in wild populations, yet this method needs to be carefully validated for each species. The goals of the study were: • Immunologically validate two methods (study 1 and 2 respectively) to extract and quantify cortisol in the hair of wild Alpine marmots. • Compare the amount of cortisol extracted from hair samples using two methods i.e. cut into fine pieces (study 1) and hair samples pulverized using a ball mill (study 2). • Determine the extent to which methods in study 2 could provide individual specific hair cortisol (HC) measures when samples were taken from the same body location. Within and between individual variations in HC levels were examined from multiple hair samples from 14 subjects in study 2. We evaluated if inter-individual variations in HC levels could be explained by sex and age. At least twice the amount of cortisol was obtained per g/hair when samples were pulverized in a ball mill prior to extraction compared to when cut into pieces. Our methods demonstrated intra-individual consistency in HC at a given time point: inter-individual variation in HC was three times larger than within individual variance. Sex and age did not impact HC levels

Modelling and simulation of heat and mass transfer for liquid type foods under high pressure processes

High Pressure (HP) Processing has turned out to be very effective in order to prolong the shelf life of some foods. This paper deals with the modelling and simulation of the effect of the combination of high pressure with thermal treatments on food. The behaviour and stability of this model are checked by various numerical examples. Furthermore, a simplified version of the model is presented and compared with the full model in terms of accuracy and computational time. The models developed provide a useful tool to design suitable industrial equipments and optimize the processes

Artificial Neural Network (ANN) in a Small Dataset to determine Neutrality in the Pronunciation of English as a Foreign Language in Filipino Call Center Agents

Artificial Neural Networks (ANNs) have continued to be efficient models in solving classification problems. In this paper, we explore the use of an A NN with a small dataset to accurately classify whet her Filipino call center agents’ pronunciations are neutral or not based on their employer’s standards. Isolated utterances of the ten most commonly used words in the call center were recorded from eleven agents creating a dataset of 110 utterances. Two learning specialists were consulted to establish ground truths and Cohen’s Kappa was computed as 0.82, validating the reliability of the dataset. The first thirteen Mel-Frequency Cepstral Coefficients (MFCCs) were then extracted from each word and an ANN was trained with Ten-fold Stratified Cross Validation. Experimental results on the model recorded a classification accuracy of 89.60% supported by an overall F-Score of 0.92

Freeze-casting for PLGA/carbonated apatite composite scaffolds: structure and properties

This paper focuses on the fabrication of three-dimensional porous PLGA-biomimetic carbonated apatite composite scaffolds by freeze-casting and using dimethyl carbonate as a solvent. Several charge/polymer ratios were tested in order to finely understand the influence of the filler rate on the scaffold porosity and mechanical and degradation properties using complementary characterization techniques (SEM, mercury porosimetry and X-ray microtomography). It was demonstrated that the apatite ratio within the composite scaffold has a strong influence in terms of architecture, material cohesion, mechanical properties and in vitro degradation properties. An optimum biomimetic apatite ratio was reached to combine good mechanical properties (higher rigidity) and material cohesion. In vitro degradation studies showed that higher apatite filler rates limited PLGA degradation and enhanced the hydrophilicity of the scaffolds which is expected to improve the biological properties of the scaffolds in addition to the bioactivity related to the presence of the apatite analogous to bone mineral