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The European corn borer, (Hübner), is the major insect pest of sweet corn in the province of Quebec, Canada, and around the world. The presence of this pest results in substantial yield decreases and profit losses for farmers. Currently, chemical insecticides are the main method used to control this insect pest. Nevertheless, there are some interesting alternatives to chemicals for controlling the European corn borer, in particular the use of predator insects. Many research studies demonstrated the effectiveness of using wasps to successfully control the corn borer. However, this biocontrol method is more expensive and complex than chemical insecticides. The main objective of this research study was to investigate the technical feasibility of spraying pupae to facilitate the implementation of this method and reduce operating costs. For this purpose, many experimental trials using were carried out in the laboratory, with the objective of finding a suitable aqueous solution that both disperses the pupae in the sprayer tank and causes them to adhere to corn leaves once sprayed. A laboratory-scale spraying system was also designed and built to check the viability of T pupae after immersion in the spray solution and spraying. The viability of pupae was investigated further using a field prototype boom sprayer. The results showed that it is possible to spray pupae while preserving their physical integrity. In addition, a mixture of guar gum and xanthan gum was found to be the most suitable for the adhesion of pupae to corn leaves. The system overall decreased the emergence rate of Trichogramma by 10% to 15% which is considered acceptable by the authors. The success of this spraying technique for controlling the European corn borer in corn crops is highly valuable and could be generalized to other predator insects. Keywords: Biocontrol, Emergence rate, European corn borer, Spraying system, Sweet corn, Trichogramma ostriniae.

Obesity epidemic continues to spread and obesity rates are increasing in the world. In addition to public health effort to reduce obesity, there is a need to better understand the underlying biology to enable more effective treatment and the discovery of new pharmacological agents. Abhydrolase domain-containing protein 11 (ABHD11) is a serine hydrolase enzyme, localized in mitochondria, that can synthesize the endocannabinoid 2-arachidonoyl glycerol (2AG) in vitro. In vivo preclinical studies demonstrated that knock-out ABHD11 mice have a similar 2AG level as WT mice and exhibit a lean metabolic phenotype. Such mice resist to weight gain in Diet Induced Obesity studies (DIO) and display normal biochemical plasma parameters. Metabolic and transcriptomic analyses on serum and tissues of ABHD11 KO mice from DIO studies show a modulation in bile salts associated with reduced fat intestinal absorption. These data suggest that modulating ABHD11 signaling pathway could be of therapeutic value for the treatment of metabolic disorders.

We explore two alternative irradiation schemes for the large ('outer') and small ('inner') angle beams that currently illuminate National Ignition Facility (NIF) and Laser Megajoule cavities. In the first, while the outer laser beams enter through the usual end laser entrance holes (LEH), the inner beams enter through slots along the cavity axis wall, illuminating the back wall of the cavity. This avoids the current interaction of the inner laser beams with the gold wall bubbles generated by the outer beams, which leads to large time-dependent changes in drive symmetry. Another scheme potentially useful for NIF uses only the outer beams. The radiative losses through the slots or from the use of outer beams only are compensated by using a smaller cavity and LEH.

Des essais preliminaires industriels de forgeage et de nettoyage du lubrifiant a la soude caustique effectues sur des lopins coule-homogeneise avaient souleve certaines interrogations sur la resistance a la corrosion de ce nouveau materiau comparativement au materiel extrude traditionnellement utilise. Cette etude en corrosion a pour objectif principal d'assurer la qualite et la possibilite d'utiliser ce materiel comme base pour l'industrie du forgeage. Le comportement en corrosion de l'alliage d'aluminium AA6082 a ete etudie par l'utilisation de methodes comparatives entre le materiel coule-forge et extrude-forge dans differents etats metallurgiques (-T6). La conclusion majeure de cette etude revele que la difference de susceptibilite en corrosion des deux materiaux n'est pas suffisamment significative pour favoriser un impact negatif sur les produits finaux de forgeage. Une investigation metallurgique avant et apres le forgeage a permis d'identifier des patrons specifiques de microstructures et des differences chimiques entre les materiaux de base. Cette analyse microstructurale met en perspective deux materiaux qui pourraient avoir des affinites differentes pour le forgeage et leur comportement en corrosion, surtout avec la presence de couches speciales en surface. Le materiel coule presente une structure ayant des grains equiaxes et une couche de segregation enrichie d'elements d'alliages tandis que le materiel extrude expose une structure fibreuse ayant une couche peripherique de gros grains recristallises. La texture microstructurale allongee pour le materiel coule-forge se transforme en une fine microstructure apres le traitement thermique -T6. Cette meme etape produit des resultats opposes pour le materiel extrude-forge en revelant une recristallisation statique qui engendre une structure grossiere a gros grains. Les trois essais caracteristiques en corrosion sur l'alliage d'aluminium AA6082 ont demontre de legeres variations concernant les resultats de degradation mais pas suffisamment pour distinguer un materiel plus resistant que l'autre. L'acquisition des courbes electrochimiques OCP a montre que le temps necessaire pour atteindre l'etat d'equilibre dans le domaine passif du materiel coule-forge etait plus long que celui extrude- forge apres 24 heures d'immersion dans une solution de 3.5% m/v de NaCI. Des essais de polarisation anodique ont permis d'identifier un potentiel de piquration (Epit) entre -0.63 a -0.54 V/SCE pour toutes les conditions metallurgiques. Le materiel coule a affiche un phenomene de piquration continu apres avoir atteint le potentiel critique Epit. Par contre, ce meme materiel semblait avoir une resistance legerement superieure a la piquration en affichant un potentiel plus noble equivalent a -0.54 V/SCE. Les analyses de microscopie optique sur les specimens corrodes ont devoile un patron de petites piqures de forme ronde et uniforme pour le materiel coule-forge et un aspect asymetrique avec quelques larges piqures de corrosion pour le materiel extrude-forge. L'analyse d'image quantitative par le logiciel CLEMEX sur les specimens corrodes par brouillard salin a revele une surface moins affectee du materiel extrude-forge sans traitement thermique comparativement a celui coule-forge (13.46% coule-forge vs 6.77% extrude-forge). Apres traitement -T6, les deux materiaux de base ont obtenu des resultats similaires du pourcentage d'aire corrode (3.62% vs 3.68%). Aucune variation significative en resistance a la fatigue-corrosion n'a ete decelee sur les deux types de materiel de base. Dans l'air, les courbe S-N ont affiche deux tendances qui caracterisent chacun des materiaux. Le materiel coule- forge a obtenu une meilleure resistance a la fatigue avec de faibles contraintes appliquees, tandis que le materiel extrude-forge a revele une resistance accrue a la fatigue durant l'imposition de contraintes severes. L'ajout d'un environnement corrosif autour des specimens a eu comme effet d'abaisser la duree de vie en fatigue d'un facteur 1x10^3 pour les deux materiaux. L'analyse macroscopique des ruptures a revele un facies granuleux et plat pour les echantillons appartenant au materiel coule-forge comparativement a d'importantes zone de clivage pour les surfaces du materiel extrude-forge. Plusieurs specimens de fatigue corroboraient la presence d'un mecanisme de propagation par striation avec bandes de cisaillement persistantes. Le facteur additif de corrosion a joue un role d'adoucissement des stries de fatigue pour les deux materiaux de forgeage.

The clinical diagnosis of deep-vein thrombosis (DVT) and pulmonary embolism (PE) is known to be unreli able. Until now, no biological marker has been found to con firm thrombosis, but help can be gained from a biological marker ruling out the diagnosis of DVT or PE, i.e., the sensitive measurement of D-dimer (DD) species. This article summa rizes our experience in introducing a rapid D-dimer test (ELISA VIDAS D-dimères test, bioMérieux) in a collaborative strategy for thrombosis diagnosis during 9 consecutive months involving 1,131 measurements. The efficacy of the DD test was very different according the type of patient, and departments where the DD test provides a real diagnostic benefit were iden tified. High clinical probability for thrombosis was encountered in 32 patients and radiology was carried out, although D-dimer was negative: none of these patients was found to have a throm bosis after radiologic examination. However, extensive prog ress must be made in test prescription to reduce the excessive rate of positive D-dimer tests (78%) and positive measurements that are not followed up by radiology (42%).