A new plastic correction for the stress intensity factor of an under-clad defect in a PWR vessel subjected to a pressurised thermal shock

For the assessment of an under-clad defect in a vessel subjected to a cold pressurised thermal shock, plasticity is considered through the amplification β of the elastic stress intensity factor K_I in the ferritic part of the vessel. An important effort has been made recently by CEA to improve the analytical tools in the frame of R&D activities funded by IRSN. The current solution in the French RSE-M code has been developed from fitted F.E. calculation results. A more physical solution is proposed in this paper. This takes into account two phenomena: the amplification of the elastic K_I due to plasticity in the cladding and a plastic zone size correction in the ferritic part.     

Expression of genes implicated in multidrug resistance in acute lymphoblastic leukemia in India

A century ago, Camillo Golgi discovered in neurons an intracellular network of anastomosing threads, impregnated by the chromoargentic reaction he had devised to stain the nervous tissue. This structure, designated by Golgi as 'internal reticular apparatus', was soon detected in a wide variety of eukaryotic cells. However, skepticism arose on the existence of the Golgi apparatus in the first decades of this century, when it was fiercely debated whether this structure represented a genuine new cell constituent or an artifact due to the deposit of metallic impregnation on diverse cytoplasmic structures. The reality of the Golgi apparatus became established unequivocally only with the application of electron microscopy; with the visualization of its fine structure, the apparatus finally achieved the status of cytoplasmic organelle, and thus, linked with Golgi's name, entered the modern era of investigation on its components, chemistry and function.     

A fatal low-molecular-weight heparin-associated thrombocytopenia after hip surgery: possible usefulness of PF4-heparin ELISA test

In 37 patients undergoing total hip replacement, a prophylactic treatment by a low-molecular-weight heparin (LMWH) was conducted for 2 weeks. They belonged to a group of 499 patients included in a multicenter clinically controlled trial comparing two LMWHs. Blood was collected 1 day before surgery (D-1) and at D+1 or D+2 and D+5 or D+6 as well as D+10 through D+14 after surgery for determinations of platelets counts and anti-Xa. Bilateral venography was performed between D+10 and D+14. A fatal heparin-associated-thrombocytopenia (HAT) occurred on D+9 in one patient and was associated with a positive platelet aggregation test. This finding was confirmed with a recent ELISA test which evidenced a high concentration of PF4-heparin dependent antibodies 72 h before the detection of thrombocytopenia. This led us to study retrospectively PF4-heparin ELISA results by testing the plasma samples of 36 other surgical patients treated under the same conditions and during the same period (four measurements per patient). Among these patients, seven had a venous thrombotic event as a treatment failure. Although some authors claimed that some post-operative thromboses may be facilitated by the presence of heparin-dependent antibodies associated with or without thrombocytopenia, no thrombocytopenia and no positive PF4-heparin ELISA test was observed in this group. Out of the 144 tests performed in these 36 patients for the detection of PF4-heparin complexes dependent antibodies, 15 results were borderline in ten patients and three results in two patients were positive. No relation was evidenced between a positive ELISA test and the occurrence of venous thrombosis. This study points out the possible usefulness of the PF4-heparin ELISA test for HAT-antibodies detection. A daily platelet count in a postoperative patient under heparin therapy, showing thrombocytopenia associated with the detection of heparin-dependent antibodies could allow an earlier and more reliable diagnosis of HAT.     

Opposite effects of lateral septal LTP and lateral septal lesions on contextual fear conditioning in mice.

The effect of fimbrial high-frequency stimulation (HFS)-induced long-term potentiation (LTP) in the lateral septum (LS) on contextual fear conditioning was studied in mice. Mice were conditioned for fear toward a novel context through the use of footshocks. The 1st experiment showed that pretraining HFS reduced significantly conditional freezing to contextual stimuli. The 2nd experiment was designed to determine whether the reduction of freezing produced by fimbrial HFS resulted from LTP in the LS rather than from LTP in other brain structures. Accordingly, mice with lesions of the LS were used and submitted to the same protocol as in the 1st experiment. Results showed that LS lesions completely abolished the impairing effect of fimbrial HFS and, as a whole, potentiated the freezing response. These data suggest that contextual fear conditioning is strongly modulated by the level of hippocampal–LS synaptic neurotransmission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Metacognitive awareness and prevention of relapse in depression: Empirical evidence.

Metacognitive awareness is a cognitive set in which negative thoughts/feelings are experienced as mental events, rather than as the self. The authors hypothesized that (1) reduced metacognitive awareness would be associated with vulnerability to depression and (2) cognitive therapy (CT) and mindfulness-based CT (MBCT) would reduce depressive relapse by increasing metacognitive awareness. They found (1) accessibility of metacognitive sets to depressive cues was less in a vulnerable group (residually depressed patients) than in nondepressed controls; (2) accessibility of metacognitive sets predicted relapse in residually depressed patients; (3) where CT reduced relapse in residually depressed patients, it increased accessibility of metacognitive sets; and (4) where MBCT reduced relapse in recovered depressed patients, it increased accessibility of metacognitive sets. CT and MBCT may reduce relapse by changing relationships to negative thoughts rather than by changing belief in thought content. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of dietary protein on the fatty acid composition and Δ6 desaturase activity of rat hepatic microsomes

Recently, significant differences between rats fed a casein diet and rats fed a soybean protein diet have been observed in hepatic phospholipid fatty acid patterns (Sjöblom, L., and Eklund, A.,Biochim. Biophys. Acta 1004, 187–192, 1990). The influence of these two diets on the Δ6 desaturase activity was investigated in the present study because the hepatic desaturase system is a source of unsaturated fatty acids. The rats fed a casein diet showed higher desaturase activity than those fed soybean protein when using either linoleic acid (P<0.005) or oleic acid (P<0.05) as substrates. The phosphatidylcholine fraction of hepatic microsomes showed increases in oleic acid (P<0.005) and 20∶3ω9 (P<0.001) levels as well as decreases in stearic acid (P<0.001), linoleic acid (P<0.005) and arachidonic acid (P<0.005) levels in rats which were fed casein rather than soybean protein. Similar differences between the two groups were also observed in the phosphatidylethanolamine and phosphatidylinositol fractions. These data indicate that the qualitative properties of the dietary protein source may influence the fatty acid pattern of rat hepatic microsomes by interfering with Δ6 desaturase activity.     

Vers les 20 kbit/s en transmission décamétrique ionosphérique : une application du traitement d’antenne sur des capteurs colocalisés

This paper presents an operational system of digital transmission within the h.f. frequency range, aiming at a significant increase of the data transfer rate compared with the current standard (4800 bit/s). Therefore, an array processing algorithm performs with a set of collocated sensors, the spatial responses of which are different one from each other. The dependence of the incoming polarization relatively to the direction of arrival induces a significant decorrelation of the received signals though no geometrical phase exists. Signal processing techniques run at the output of the spatial filter resorting for the synchronisation and the filtering (lms algorithm) to classical and well-tested techniques involving training sequences. An experimental radio link with a 250 km range has been set up to test the sensibility of the performances in reception regarding the choice of waveforms. The operational results reach the expected goal as the data transfer rate increases up to 20 kbit/s in a bandwidth of 6 kHz.     

Effects of double-bond configuration on interaction between a moth sex pheromone component and its receptor

The dependence of the electrophysiological activity on the change of double-bond configuration of (Z)-5-decenyl acetate, a pheromone component of the turnip moth,Agrotis segetum, and a dienic analog, (E)-2,(Z)-5-decadienyl acetate, have been investigated by single-cell measurements and molecular mechanics calculations (MM2). A previously reported model for the interaction between a moth sex pheromone component and its receptor has been refined. This new model gives an essentially quantitative correlation between the measured activities and the calculated conformational energies for a biologically active conformation defined by the model. Previously obtained structure-activity results for chain-elongated analogs of (Z)-5-decenyl acetate are significantly improved by the refined model. The effect of a change of the double-bond configuration on the substrate-receptor interaction is not additive but depends on the conformational properties of the entire molecule.