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711.
712.
Viet Hung Nguyen Jérôme Saint-Martin Damien Querlioz Fulvio Mazzamuto Arnaud Bournel Yann-Michel Niquet Philippe Dollfus 《Journal of Computational Electronics》2013,12(2):85-93
By means of numerical simulation based on the Green’s function formalism on a tight binding Hamiltonian, we investigate different possibilities of achieving a strong effect of negative differential resistance in graphene tunnel diodes, the operation of which is controlled by the interband tunneling between both sides of the PN junction. We emphasize on different approaches of bandgap nanoengineering, in the form of nanoribbons (GNRs) or nanomeshes (GNMs), which can improve the device behaviour. In particular, by inserting a small or even zero bandgap section in the transition region separating the doped sides of the junction, the peak current and the peak-to-valley ratio (PVR) are shown to be strongly enhanced and weakly sensitive to the length fluctuations of the transition region, which is an important point regarding applications. The study is extended to the tunneling FET which offers the additional possibility of modulating the interband tunneling and the PVR. The overall work suggests the high potential of GNM lattices for designing high performance devices for either analog or digital applications. 相似文献
713.
Viet Dung Le Michel Gratton Michaël Caliez Arnaud Frachon Didier Picart 《Journal of Materials Science》2010,45(21):5802-5813
This article deals with the characterization of the static mechanical behavior of an energetic material. Due to its constituents (crystals and a polymeric binder), the behavior is complicated to model. A specific experimental protocol has been proposed in this article. It involves uniaxial tensile and compressive tests, compression under confinement and dynamic mechanical analysis. A constitutive law has been developed. The behavior is described using a Maxwell’s model, in which all the components are influenced by an isotropic damage. The first component takes into account an elasto-plastic behavior. The yield stress evolution is described using a parabolic criterion and an isotropic hardening law. The plastic flow rule is non-associated. A linear visco-elastic behavior is used for the other components. Numerical simulations show that experimental data are quite well reproduced. The last part of the article is devoted to a discussion highlighting the future improvements. 相似文献
714.
Initially described as lytic bodies due to their degradative and recycling functions, lysosomes play a critical role in metabolic adaptation to nutrient availability. More recently, the contribution of lysosomal proteins to cell signaling has been established, and lysosomes have emerged as signaling hubs that regulate diverse cellular processes, including cell proliferation and cell fate. Deciphering these signaling pathways has revealed an extensive crosstalk between the lysosomal and cell cycle machineries that is only beginning to be understood. Recent studies also indicate that a number of lysosomal proteins are involved in the regulation of embryonic and adult stem cell fate and identity. In this review, we will focus on the role of the lysosome as a signaling platform with an emphasis on its function in integrating nutrient sensing with proliferation and cell cycle progression, as well as in stemness-related features, such as self-renewal and quiescence. 相似文献
715.
Elodie Hedou Sara Douceau Arnaud Chevilley Alexandre Varangot Audrey M. Thiebaut Hortense Triniac Isabelle Bardou Carine Ali Mike Maillasson Tiziana Crepaldi Paolo Comoglio Eloïse Lemarchand Vronique Agin Benoit D. Roussel Denis Vivien 《International journal of molecular sciences》2021,22(24)
Tissue-type plasminogen activator (tPA) plays roles in the development and the plasticity of the nervous system. Here, we demonstrate in neurons, that by opposition to the single chain form (sc-tPA), the two-chains form of tPA (tc-tPA) activates the MET receptor, leading to the recruitment of N-Methyl-d-Aspartate receptors (NMDARs) and to the endocytosis and proteasome-dependent degradation of NMDARs containing the GluN2B subunit. Accordingly, tc-tPA down-regulated GluN2B-NMDAR-driven signalling, a process prevented by blockers of HGFR/MET and mimicked by its agonists, leading to a modulation of neuronal death. Thus, our present study unmasks a new mechanism of action of tPA, with its two-chains form mediating a crosstalk between MET and the GluN2B subunit of NMDARs to control neuronal survival. 相似文献
716.
Influence of ecological cultivation on virgin olive oil quality 总被引:1,自引:1,他引:0
Francisca Gutiérrez Teresa Arnaud Miguel A. Albi 《Journal of the American Oil Chemists' Society》1999,76(5):617-621
The quality of oil extracted from ecologically cultivated olives of the Picual variety was compared with oil extracted from
Picual olives cultivated using conventional methods. Olive trees were grown in a two-section plot. Fruits from each plot were
harvested at various stages of ripeness, and acidity value, peroxide index, ultraviolet absorption at 232 and 270 nm, stability
to oxidation, sensory analysis, fatty composition, and contents of tocopherols, phenolic compounds, and sterols were determined
on oil extracted from each treatment. The results showed that the organic virgin olive oil was of a superior quality to the
conventional virgin olive oil in all the quality parameters analyzed. 相似文献
717.
D. Montet F. Servat M. Pina J. Graille P. Galzy A. Arnaud H. Ledon L. Marcou 《Journal of the American Oil Chemists' Society》1990,67(11):771-774
Chemical synthesis of N-ε-acyllysines on an industrial scale corresponds to new requirements in the surfactant field; only
one chemical synthesis process is currently known for this type of molecule. A number of organic synthesis conducted in the
laboratory so far have not made it possible to consider industrial development. However, biotechnologically, it has been shown
that this molecule is easily accessible using a commercially available fixed lipase. Synthesis is carried out by causing a
triglyceride to react with the lysine either with or without a solvent. The latter method gives the best results at the current
stage of research. Given the availability of at least one fixed lipase on the market today, and the possibility of directly
applying the reaction using oils, this reaction could be scaled up rapidly for industrial development. 相似文献
718.
Update on peptidylarginine deiminases and deimination in skin physiology and severe human diseases 总被引:2,自引:0,他引:2
719.
D Blum Y Wu MF Nissou S Arnaud Alim-Louis-Benabid JM Verna 《Canadian Metallurgical Quarterly》1997,751(1):139-142
We report a patient with Sj?gren's syndrome and multiple gastrointestinal manifestations who successfully responded to therapy with ursodeoxycholic acid. Our patient had sialoadenitis with dry mouth, dry eyes, arthralgia, chronic pancreatitis, sclerosing cholangitis, and pulmonary infiltrations. The first signs of disease were the symptoms of chronic pancreatitis followed by icterus, caused by extrahepatic bile duct obstruction. Sclerosing cholangitis was diagnosed by liver biopsy and endoscopic retrograde cholangiography. Sialoadenitis, causing dry mouth, was verified by buccal biopsy. Pulmonary infiltrations were seen on standard chest x-ray, and also shown by high-resolution computed tomography examination. Obstructive icterus and even pulmonary infiltration responded successfully to treatment with ursodeoxycholic acid. 相似文献
720.
The relative biologic activities of native human parathyroid hormone, hPTH (1-84), native bovine parathyroid hormone, bPTH (1-84), and their respective synthetic, NH2-terminal, biologically-active (1-34) fragments were compared in vitro using adenylate cyclase preparations from human, chicken, and rat renal cortex. The concentrations of the hormones required for half-maximal stimulation of the enzymes were determined from dose response curves. bPTH (1-84) had greater apparent activity than hPTH (1-84), using rat or chicken renal adenylate cyclase, but, with human renal adenylate cyclase, the apparent activities of the two hormones were equal. Synthetic hPTH (1-34) possessed about 1/10 of the apparent activity of hPTH (1-84) in all three adenylate cyclase systems. However, (GLU22)bPTH (1-34) was about equal inapparent activity to bPTH (1-84) in the three systems. We propose that different rates of hormone degradation at or near renal receptor sites may be responsible for the dependence of the relative biologic activity on the assay system used. In the case of hPTH a peptide chain longer than (1-34) may be required for the full biologic activity of the hormone... 相似文献