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361.
Kyungreem HanHyun Woong Kwon Hyuk KangJinwoong Kim Myung-Shik LeeM.Y. Choi 《Physica A》2012,391(3):686-692
We propose a model for macroautophagy and study the resulting dynamics of autophagy in a system isolated from its extra-cellular environment. It is found that the intracellular concentrations of autophagosomes and autolysosomes display oscillations with their own natural frequencies. Such oscillatory behaviors, which are interrelated to the dynamics of intracellular ATP, amino acids, and proteins, are consistent with the very recent biological observations. Implications of this theoretical study of autophagy are discussed, with regard to the possibility of guiding molecular studies of autophagy. 相似文献
362.
DoYong Kwon 《Acta Mathematica Hungarica》2012,134(4):472-480
We derive sufficient conditions under which all but two zeros of reciprocal polynomials lie on the unit circle, and specify
the location of the remaining two zeros. 相似文献
363.
G. L. Zhang C. L. Zhang H. Q. Zhang C. J. Lin D. Y. Pang X. K. Wu H. M. Jia G. P. An Z. D. Wu X. X. Xu F. Yang Z. H. Liu S. Kubono H. Yamaguchi S. Hayakawa D. N. Binh Y. K. Kwon N. Iwasa M. Mazzocco M. La Commara M. Romoli C. Signorini 《The European Physical Journal A - Hadrons and Nuclei》2012,48(5):1-7
The quasi-elastic scattering angular distribution of the proton drip line nucleus 17F on a 12C target was measured at 60 MeV. The experimental data have been compared with the theoretical analysis based onto optical model and continuum discretized coupled channels (CDCC). The couplings between breakup and elastic scattering channels, and between inelastic and elastic scattering channels resulted very weak. In order to explore the breakup effects the total reaction cross-section was deduced from the angular distribution of the quasi-elastic scattering data, and then compared with the existing data for the other weakly and tightly bound nuclei on 12C target using a universal function. From this comparison, we concluded that the breakup effect is not important for weakly bound projectiles on the light target as obtained also with the CDCC analysis. 相似文献
364.
We investigated tunable gigahertz-resonators, which is based on the application of a telescoped double-walled carbon-nanotube that can be used repeatedly and operate at a single frequency or have a relatively narrow frequency range, via classical molecular dynamics simulations of a double-walled carbon-nanotube. Two types of telescoped double-walled carbon-nanotube resonators were compared with each other; one was bridge-type and another was cantilever-type, and one side was connected to a position controller in order to achieve a telescoped carbon-nanotube. The frequency bandwidth of our cantilevered type design can exceed that of the bridged type. Our simulations showed that such a system can tune it up its resonance frequency by controlling the length of oscillating carbon-nanotube resonator. 相似文献
365.
Effects of post-annealing on electrical properties of amorphous Ga-doped Zn–Sn–O semiconductor films
Dong-Ho Kim Hye-Ri Kim Jung-Dae Kwon Gun-Hwan Lee Juyun Park Yong-Cheol Kang 《Journal of Non》2012,358(18-19):2616-2619
We investigated the effect of post-annealing on the electrical properties of amorphous gallium-zinc-tin oxide (a-GZTO) films with different Ga contents. The films were deposited at room temperature by sputtering and annealed in air for 1 h. It was found that the doping with Ga, which acts as the carrier suppressor, contributes to the thermal stability of characteristic properties of a-GZTO thin films. The film with a small amount of Ga showed significant variations in carrier concentration according to the annealing temperature. Increases in carrier concentration and mobility can be ascribed to the reduction of subgap density of states by annealing. After annealing at 400 °C, however, the enrichment of Zn cations in surface region resulted in considerable changes in chemical bonding states and consequently, the carrier concentration decreased by two orders of magnitude for the low Ga-doped ZTO film. 相似文献
366.
Lee D Kwon D Ko W Joo J Seo H Lee SS Jeon S 《Chemical communications (Cambridge, England)》2012,48(57):7182-7184
A rapid and facile signal enhancement method for detecting alpha-fetoprotein (AFP) was developed using the magnetic agglomeration of ferromagnetic nanoparticles and microcantilever sensors. The resonance frequency and deflection of the cantilevers were found to be more than 10-fold greater than that before physical agglomeration of the free nanoparticles around the magnetized nanoparticles. 相似文献
367.
(Bio)degradation in response to external stimuli (stimuli-responsive degradation, SRD) is a desired property in constructing novel nanostructured materials. For polymer-based multifunctional drug delivery applications, the degradation enables fast and controlled release of encapsulated therapeutic drugs from delivery vehicles in targeted cells. It also ensures the clearance of the empty device after drugs are delivered to the body. This review summarizes recent development of various strategies to the design and synthesis of self-assembled micellar aggregates based on novel amphiphilic block copolymers having different numbers of stimuli-responsive cleavable elements at various locations. These cleavable linkages including disulfide, acid-labile, and photo-cleavable linkages are incorporated into micelles, and then are cleaved in response to cellular triggers such as reductive reaction, light, and low acid. The well-designed SRD micelles have been explored as controlled/enhanced delivery vehicles of drugs and genes. For future design and development of effective stimuli-responsive degradable micelles toward tumor-targeting delivery applications in vivo, a high degree of control over degradation for tunable release of encapsulated anticancer drugs as well as bioconjugation for active tumor-targeting is required. 相似文献
368.
Cho KJ Ryu DW Kwak HY Lee JW Lee WR Lim KS Koh EK Kwon YW Hong CS 《Chemical communications (Cambridge, England)》2012,48(59):7404-7406
A tetranuclear Fe(III)(2)Mn(III)(2) compound was prepared using highly blocked precursors. The well-isolated molecular entity associated with appropriate magnetic anisotropy allows for single-molecule magnet behavior. 相似文献
369.
J Shin NS Kang KH Kim TW Lee JI Jin M Kim K Lee BK Ju JM Hong DH Choi 《Chemical communications (Cambridge, England)》2012,48(68):8490-8492
A new anthracene-based X-shaped conjugated molecule, HBTATHT, was synthesized. Thin film transistors based on unannealed HBTATHT showed a carrier mobility of 0.15 cm(2) V(-1) s(-1) (I(on/off) = 7.9 × 10(6)). Further, a solution processed solar cell made of HBTATHT exhibited promising power conversion efficiencies of 4.84% and 4.70% with PC(61)BM (1?:?0.8 wt ratio) and PC(71)BM (1?:?0.6 wt ratio), respectively. 相似文献
370.
An array of N-tosylated α-aminoalkylallenic esters was prepared and their cyclization under the influence of nucleophilic phosphine catalysts was explored. The α-aminoalkylallenic esters were prepared through aza-Baylis-Hillman reactions or novel DABCO-mediated decarboxylative rearrangements of allenylic carbamates. Conversion of these substrates to 3-carbethoxy-2-alkyl-3-pyrrolines was facilitated through Ph(3)P-catalyzed intramolecular γ-umpolung addition. 相似文献