La réputation sociale de l'enfant en milieu scolaire.

Studied the social reputations of elementary school children. Ss were 76 2nd-grade (mean age 7.5 yrs), 71 3rd-grade (mean age 8.5 yrs), and 83 4th-grade students (mean age 9.7 yrs). Using the peer nomination technique, Ss were assessed collectively on 8 dimensions requiring both social and academic judgments. A cluster analysis was performed to identify groups with different sociometric profiles. Correlations between peer evaluations and teacher evaluations of Ss' social reputations were determined. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The bioavailability of raspberry anthocyanins and ellagitannins in rats

The fate of anthocyanins and ellagitannins in rats was monitored following ingestion of raspberry juice. After 1 h low nM concentrations of unmetabolised anthocyanins were present in plasma but these declined by 2 h and after 4 h they were no longer detectable. For the first 2 h there was an almost full recovery of anthocyanins as they passed from the stomach through the duodenum/jejunum and into the ileum. After 3 h less than 50% were recovered, and the levels declined rapidly thereafter. Excretion of raspberry anthocyanins in urine over a 24 h period was equivalent to 1.2% of the amount ingested. Trace quantities of anthocyanins were detected in the caecum, colon and faeces and they were absent in extracts of liver, kidneys and brain. Urine also contained a number of phenolic acids but most were present in quantities well in excess of the 918 nmol of anthocyanins present in the ingested juice. These findings indicate that raspberry anthocyanins per se are poorly absorbed, probably prior to reaching the ileum, and that substantial amounts pass from the small to the large intestine where they are degraded by colonic bacteria. Ellagitannins disappeared in the stomach without accumulation of ellagic acid.     

Analysis of improved positioning in five-axis ruled surface milling using envelope surface

This article covers side milling of ruled surfaces using a milling cutter. Flank milling is useful for machining objects such as impellers, turbine blades, fan vanes and all workpieces defined by non-developable, ruled surfaces. In the present article, we first introduce two types of positioning on ruled surfaces developed within the Toulouse Mechanical Engineering Laboratory. The positioning studied is taken from the geometric situation not taking the instantaneous speed of rotation of the milling cutter into account. The swept profile of the tool is then determined based on the tool motion. Having defined the envelope surface, we seek to analyse improved and standard positioning errors comparing envelope surfaces with the ruled surface. We then introduce an example to illustrate positioning developed through a first theoretical study before experimentation including machining and measurement of the test piece. Finally, we give our conclusions as to the validity of improved positioning without taking the instantaneous speed of rotation of the milling cutter into account.     

Phenolics from purple grape, apple, purple grape juice and apple juice prevent early atherosclerosis induced by an atherogenic diet in hamsters

Knowledge of the effects of processing on the antioxidant properties of fruits is limited. We investigated the processing of apple (A) and purple grape (PG) and their juices (AJ and PGJ) in hypercholesterolemic hamsters. Five groups of eight hamsters each were fed an atherogenic diet for 12 wk. They received daily by gavage either 7.14 mL/(kg x day) of mashed A or PG, or the same volume of AJ or PGJ, or water as control. Plasma cholesterol, non-HDL cholesterol, liver superoxide dismutase and glutathione peroxidase activities, and thiobarbituric acid reactive substances were efficiently reduced by the fruits and their juices compared with controls, whereas plasma antioxidant capacity was increased and aortic fatty streak area was decreased from 48 to 93%. For each of these parameters, the efficacy was PGJ > PG > AJ > A. The results show for the first time that long-term consumption of antioxidants supplied by apple and purple grape, especially phenolic compounds, prevents the development of atherosclerosis in hamsters, and that processing can have a major impact on the potential health benefits of a product. The underlying mechanism is related mainly to increased antioxidant status and improved serum lipid profile.     

Characterisation of the workpiece dilatation phenomenon during machining using the neural network method. Application to NC turning

Dilatation of workpieces during machining is a major source of defects. With the current trend for re-treatment of cutting and cleaning fluids becoming compulsory, lubrication by a stream of oil and dry machining are becoming more widely used in aluminium alloy machining. Indeed, this makes it easier to recycle chippings and greatly simplifies the cleaning and grease removal phases for workpieces that are compulsory before any finishing surface treatment. However, the workpiece’s deformation during machining must be taken into account. This is especially true for NC turning of machining diameters with very tight tolerances. Here we propose a method based on the use of a neural network intended to model changes in the workpiece’s dimensions to correct tool paths. This study covered machining of workpieces made of 2017 T4 aluminium alloy during the turning phase. We first conducted preliminary tests on a workpiece to highlight workpiece dilatation. We then implemented a neural network to predict this deformation to be able to compensate for it. The results of a first test campaign gave us knowledge of the network then a second test campaign was used to validate that network. To finish off, we machined a test workpiece in order to test and analyse network performance.     

Ultrastructural study of the differentiation of mammary buds during the fetal life of female mice

On mouse female fetuses, mammary gland bud development was studied ultrastructurally. This development is characterized by: - primary bud dichotomization into two secondary ductules, - lumen formation in the primary bud and in the secondary ductules. The lumen is formed by necrosis of central cells and around it cells are organized in an epithelium.     

Antioxidant capacity and angiotensin I converting enzyme inhibitory activity of a melon concentrate rich in superoxide dismutase

Antioxidant capacity and angiotensin 1-converting enzyme (ACE) inhibitory activity of a melon concentrate rich in superoxide dismutase (SOD-MC) were investigated in vitro. The total antioxidant capacity (TAC) was measured by the Trolox equivalent antioxidant capacity assay (TEAC), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, and the ferric reducing antioxidant power assay (FRAP). The ability of the extract to scavenge three specific reactive oxygen species (superoxide radical anion (O(2)(-)), hydroxyl radical (HO()) and hydrogen peroxide (H(2)O(2))) was also investigated in order to better evaluate its antioxidant properties. Even if the measures of TAC were relatively low, results clearly established an antioxidant potential of SOD-MC that exhibited the highest radical-scavenging activity towards O(2)(-), with a IC(50) 12-fold lower than that of H(2)O(2) or HO(). This lets hypothesis that the antioxidant potential of SOD-MC could be mainly due to its high level of SOD. Moreover, for the first time, an ACE inhibitory activity of SOD-MC (IC(50)=2.4±0.1mg/mL) was demonstrated, showing that its use as a functional food ingredient with potential preventive benefits in the context of hypertension may have important public health implications and should be carefully considered.     

Raspberry juice consumption, oxidative stress and reduction of atherosclerosis risk factors in hypercholesterolemic golden Syrian hamsters

The effects of raspberries on early atherosclerosis in Syrian hamsters were investigated using three juices prepared from var. Cardinal, Glen Ample and Tulameen berries. The hamsters received an atherogenic diet for 12 weeks and at the same time a juice at a daily dose corresponding to the consumption of 275 ml by a 70 kg human. A control group received the same diet with water instead juice. The principal polyphenolic compounds in the juices were anthocyanins and ellagitannins, which were present at concentrations of 218-305 μg mL(-1) and 45-72 μg mL(-1), respectively. The three juices had similar but not identical effects. They all inhibited cardiac and aortic production of superoxide anion and increased hepatic glutathione peroxidase activity although only Tulameen juice brought about a significant increase in superoxide dismutase activity. Glen Ample was the only juice to significantly increase plasma paraoxonase activity. All the juices lowered plasma triglyceride level while consumption of Tulameen and Cardinal, but not Glen Ample, significantly lowered plasma total cholesterol and LDL-cholesterol. Cardinal was the sole juice to significantly increase HDL-cholesterol and likewise it also significantly reduced body weight. These findings suggest that moderate consumption of raspberry juices can help to prevent the development of early atherosclerosis, with the underlying mechanisms related to improved antioxidant status and serum lipid profiles.     

A moderate consumption of Côtes du Rhône red wines affects the progression of aortic lesions,and reduces oxidative stress and p22<Superscript>phox</Superscript>NADPH oxidase activation in an experimental model of diet-induced atherosclerosis,according to the vinification process

Côtes du Rhône red wines prepared from both different types of grape and processing were tested in hamsters receiving an atherogenic diet for 12 weeks and a daily gavage with 12% ethanol, red wines from vinification by flash release (GRE FD, SYR FD and BLEND FD), by tanisage (BLEND TAN), by traditional vinification (BLEND), or water as control. Except BLEND TAN, consumption of wines lowered plasma total and LDL-cholesterol. Aortic lipid deposits were reduced by ethanol (30%), wines (54% on average) or BLEND TAN (65%). Cardiac production of superoxide anion decreased from 20% (BLEND and BLEND TAN) to 33% (SYR FD and BLEND FD). The expression of NAD(P)H oxidase decreased by 44% (SYR FD), 26% (BLEND), 47% (BLEND FD) and 44% (BLEND TAN). Except ethanol and GRE FD, wines increased uricemia by 15% on average. These findings indicate that chronic consumption of red wine has potential beneficial effects to prevent the development of atherosclerosis. Prevention of NAD(P)H oxidase induction and preservation of aortic lipids oxidation likely contribute to this effect.