INFLUENCE DU TRAITEMENT THERMIQUE ET MECANIQUE SUR LES PROPRIETES MECANIQUES ET STRUCTURALES DES ACIERS AU MANGANESE MOULES.

Molded Steel with manganese have approximately 1,2% C and 12% Mn, this high proportion of manganese gives to this alloy a stable austenitic structure on a room temperature. The experimental methods used for metallurgical studies are spark optical emission spectroscopy, optical microscopy, scanning electron microscopy, micro-hardness and hardnesss test. Steel 1 is heat-treated constitued by 15,516 % of manganese, 2,677 % of chromuim and 1,286 % of carbon. Steel 2 is mechanically treated contains 13,454 % of manganese, 1,721 % of chromuim and 1,213 % of carbon . Steel 1 has sustained quench at 1070°C, for two differents maintaining times on oven 30 and 50 minutes for a thickness of 150 millimeters then for two differents thickness 100 and 150 millimeters for a time of 50 minutes. When maintaining time on the oven increase for low dimension, surface’s alloy become more ductile. We have applied a mechanical treatement manually on steel 2 surface, his hardness increase significantly

Hadron calorimeter with MAPD readout in the NA61/SHINE experiment

The modular hadron calorimeter with micro-pixel avalanche photodiodes readout for the NA61/SHINE experiment at the CERN SPS is presented. The calorimeter consists of 44 independent modules with lead-scintillator sandwich structure. The light from the scintillator tiles is captured by and transported with WLS-fibers embedded in scintillator grooves. The construction provides a longitudinal segmentation of the module in 10 sections with independent MAPD readout. MAPDs with pixel density of $~10^{4}$/mm$^2$ ensure good linearity of calorimeter response in a wide dynamical range. The performance of the calorimeter prototype in a beam test is reported

Impact of hyperhomocysteinemia on histo-morphometry and histochemistry of pancreas in sand rat, Psammomys obesus

Introduction. The sand rat, Psammomys obesus, a diurnal rodent, which lives in the south-east of the Algerian Sahara, is an excellent animal model for the study of diabetes, atherosclerosis, and metabolic syndrome. Hyperhomocysteinemia (Hhcy), defined by high plasma homocysteine level, is associated with many diseases affecting various organs (heart, blood vessels, liver…). Objectives. The objective of this study was to determine the effect of Hhcy on the sand rats pancreas. Material and methods. The rats were divided into two groups: a control group received its natural diet with halophile plant of the Chenopodiacae family (Suaedamollis), and an experimental group received the same diet associated with an intraperitoneal administration of methionine (150 mg/kg body weight/day) during 6 months. Histological and histochemical analysis of Psammomys pancreas were realized and completed by a morphometric study. Results. The methionine excess led to a hyperhomocysteinemia in Psammomys obesus. Several alterations were observed in pancreas extracellular matrix of hyperhomocysteinemic rats, marked by an accumulation of fibrillar collagens, and glycoproteins leading to a fibrosis. This accumulation was observed in the Langerhans islets, and in the exocrine pancreas (interstitial tissue, around blood vessels, and excretory channels). A disorganization of the vascular wall, and a micro- and macrovesicular steatosis were also observed in the pancreas of hyperhomocysteinemic rats. Conclusion. The hyperhomocysteinemia, generated by the methionine excess, leads to a pancreatic extracellular matrix remodeling in Psammomys obesus

Advanced Technologies for Oral Controlled Release: Cyclodextrins for oral controlled release

Cyclodextrins (CDs) are used in oral pharmaceutical formulations, by means of inclusion complexes formation, with the following advantages for the drugs: (1) solubility, dissolution rate, stability and bioavailability enhancement; (2) to modify the drug release site and/or time profile; and (3) to reduce or prevent gastrointestinal side effects and unpleasant smell or taste, to prevent drug-drug or drug-additive interactions, or even to convert oil and liquid drugs into microcrystalline or amorphous powders. A more recent trend focuses on the use of CDs as nanocarriers, a strategy that aims to design versatile delivery systems that can encapsulate drugs with better physicochemical properties for oral delivery. Thus, the aim of this work was to review the applications of the CDs and their hydrophilic derivatives on the solubility enhancement of poorly water soluble drugs in order to increase their dissolution rate and get immediate release, as well as their ability to control (to prolong or to delay) the release of drugs from solid dosage forms, either as complexes with the hydrophilic (e.g. as osmotic pumps) and/ or hydrophobic CDs. New controlled delivery systems based on nanotechonology carriers (nanoparticles and conjugates) have also been reviewed