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51.
52.
Truong LX Nguyen Chung Kwon Kim Jun-Hee Cho Kyung-Hoon Lee Jee-Yin Ahn 《Experimental & molecular medicine》2010,42(8):583-595
Neurotrophins protect neurons against excitotoxicity; however the signaling mechanisms for this protection remain to be fully elucidated. Here we report that activation of the phosphatidyl inositol 3 kinase (PI3K)/Akt pathway is critical for protection of hippocampal cells from staurosporine (STS) induced apoptosis, characterized by nuclear condensation and activation of the caspase cascade. Both nerve growth factor (NGF) and brain-derived growth factor (BDNF) prevent STS-induced apoptotic morphology and caspase-3 activity by upregulating phosphorylation of the tropomyosin receptor kinase (Trk) receptor. Inhibition of Trk receptor by K252a altered the neuroprotective effect of both NGF and BDNF whereas inhibition of the p75 neurotrophin receptor (p75NTR) had no effect. Impairment of the PI3K/Akt pathway or overexpression of dominant negative (DN)-Akt abolished the protective effect of both neurotrophins, while active Akt prevented cell death. Moreover, knockdown of Akt by si-RNA was able to block the survival effect of both NGF and BDNF. Thus, the survival action of NGF and BDNF against STS-induced neurotoxicity was mediated by the activation of PI3K/Akt signaling through the Trk receptor. 相似文献
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Truong T.K. Wang L.J. Reed I.S. Hsieh W.S. 《IEEE transactions on image processing》2000,9(11):1988-1995
A new cubic convolution spline interpolation (CCSI )for both one-dimensional (1-D) and two-dimensional (2-D) signals is developed in order to subsample signal and image compression data. The CCSI yields a very accurate algorithm for smoothing. It is also shown that this new and fast smoothing filter for CCSI can be used with the JPEG standard to design an improved JPEG encoder-decoder for a high compression ratio. 相似文献
55.
No-reference image quality assessment using structural activity 总被引:2,自引:0,他引:2
Presuming that human visual perception is highly sensitive to the structural information in a scene, we propose the concept of structural activity (SA) together with a model of SA indicator in a new framework for no-reference (NR) image quality assessment (QA) in this study. The proposed framework estimates image quality based on the quantification of the SA information of different visual significance. We propose some alternative implementations of SA indicator in this paper as examples to demonstrate the effectiveness of the SA-motivated framework. Comprehensive testing demonstrates that the model of SA indicator exhibits satisfactory performance in comparison with subjective quality scores as well as representative full-reference (FR) image quality measures. 相似文献
56.
Jürgen Fuhrmann André Fiebach Manfred Uhle Andreas Erdmann Charles R. Szmanda Chi Truong 《Microelectronic Engineering》2009,86(4-6):792-795
Pattern doubling by cross-linking of a spacer triggered by residual acid diffusion from a previously developed primary structure into the spacer is a possible option to create the necessary structure widths for the 32 nm node with current exposure technology by pattern doubling. A particular advantage of this process step would be the self-alignment to the primary structure, which would render a second exposure step unnecessary. In the paper, we present a new prototypical model of the bake step of this process and discuss the dependency of the desired behavior on parameters of the model. 相似文献
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58.
Multi‐Species Multi‐Channel (MSMC): An Ab Initio‐based Parallel Thermodynamic and Kinetic Code for Complex Chemical Systems
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Multi‐Species Multi‐Channel (MSMC) is an ab initio parallel program to calculate thermodynamic quantities (e.g., , , , and , time‐dependent species profiles, and rate coefficients as functions of temperature and pressure for complex chemical reaction systems, which consist of multiple stable species and multiple reaction channels interconnecting them. Thermodynamic properties of the species involved are calculated using statistical mechanics with molecular information from electronic structure calculations. Temperature‐ and pressure‐dependent behaviors are rigorously characterized within the eigenpair master equation/Rice–Ramsperger–Kassel–Marcus (ME/RRKM) framework. Corrections, e.g., for hindered internal rotation and tunneling treatment, are included. With the implementation of an ultra‐high precision package and rigorous matrix setup, MSMC is able to correctly mimic real behaviors of different types of chemical systems. Different eigenpair‐based approaches to extract phenomenological/macroscopic rate coefficients are implemented for different applications. Moreover, a friendly and platform‐independent graphical‐user‐interface (GUI) is provided to facilitate the use of MSMC and the pre‐/postcalculation data visualization/analysis on the fly. The program can be freely downloaded at https://sites.google.com/site/msmccode/ . 相似文献
59.
Hung Truong Ngoc Ádám Adél Varga Gábor Dudás Csilla Kele Zoltán Sipos Pál Pálinkó István 《Structural chemistry》2017,28(2):475-478
Structural Chemistry - 2-Cyano-2-(hydroxyimino)dithioacetic acid was prepared starting from cyanoacetic acid methylester via 2-cyano-2-(hydroxyimino)acetic acid methylester. Before thionation, the... 相似文献
60.
A right R-module M is called simple-direct-injective if, whenever, A and B are simple submodules of M with A?B, and B?⊕M, then A?⊕M. Dually, M is called simple-direct-projective if, whenever, A and B are submodules of M with M∕A?B?⊕M and B simple, then A?⊕M. In this paper, we continue our investigation of these classes of modules strengthening many of the established results on the subject. For example, we show that a ring R is uniserial (artinian serial) with J2(R) = 0 iff every simple-direct-projective right R-module is an SSP-module (SIP-module) iff every simple-direct-injective right R-module is an SIP-module (SSP-module). 相似文献