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1.
The effect of duty cycle of pulsed dc currents on the critical length-current density product, (jlc), was measured using the Blech-Kinsbron edge-displacement technique [Thin Solid Films 25, 327 (1975)]. Unencapsulated Al edge-displacement segments mere stressed at various duty cycles and the critical lengths, the so-called “Blech lengths”, were measured. It was found that jlc increased with decreasing duty cycle. We measured a factor of 2.6 increase in jlc for the 25% duty cycle as compared to dc. This duty cycle dependence of Blech length implies that electromigration resistance for an integrated circuit would be increased for small duty cycle operation by increasing the fraction of interconnects which are sub-Blech-length and are not susceptible to EM damage 相似文献
2.
Quinine and quinidine are reported to potentiate the behavioural effects of serotonergic agents and monoamine uptake inhibitors. We have therefore investigated the presynaptic actions of quinine and quinidine on monoamine uptake and release in rat brain tissue in vitro. Quinidine evoked the release of [3H]5-HT, [3H]noradrenaline and [3H]dopamine from pre-loaded rat brain slices in a concentration dependent manner with EC50 values of 175, 486 and 150 microM, respectively. Quinine induced [3H]monoamine release with similar potencies. Both quinine and quinidine also inhibited the active uptake of [3H]5-HT, [3H]noradrenaline and [3H]dopamine into rat brain synaptosomes with IC50 values in the range 0.13-12.4 microM. The potency of each drug to inhibit [3H]5-HT uptake was significantly higher than that for [3H]noradrenaline or [3H]dopamine. The relative potency of quinidine compared to quinine was more marked in the case of [3H]5-HT (58-fold) than for [3H]noradrenaline (3-fold) or [3H]dopamine (4-fold). The inhibition of [3H]5-HT uptake by quinine and quinidine was competitive in nature and corresponded with the potencies of these drugs to inhibit [3H]paroxetine binding. No correlation was observed between the potencies of quinine and quinidine to induce the release of [3H]monoamines and to inhibit their uptake, suggesting that these effects are mediated by two distinct mechanisms. We conclude that the presynaptic actions of quinine and quinidine on monoamine uptake and release may be implicated in their potentiation of the effects of serotonergic agents and uptake blockers. 相似文献
3.
Clement Ampadu 《Quantum Information Processing》2012,11(6):1921-1929
In this paper we consider the model with decoherence operators introduced by Brun et?al. (Phys Rev A 67:032304, 2003) which has recently been considered in the two-dimensional setting by Ampadu (Commun Theor Phys, 2011) to obtain the limit of the decoherent quantum walk. 相似文献
4.
A Moise R Salamon M Raissis P Nanopoulos B Clement 《Computers and biomedical research》1986,19(4):379-389
Adjustment for covariates (or poststratification) is frequently used in the analysis of randomized clinical trials. The purpose of such analysis is mainly to eliminate some residual bias resulting from any imbalance between treatment groups for some important covariates. Usually, covariate effect is modeled with the data at hand. In this paper, we present a new method of poststratification ("constrained poststratification") which consists of estimating the prognostic significance of covariates in a large historical data base, transferring the model's coefficients into the (smaller) randomized trial data set, and estimating treatment effects conditional on this a priori information. In a simulated experiment, constrained poststratification allowed not only reduction of the bias but also enhancement of the efficiency of the estimation of treatment effect. 相似文献
5.
The microfluidics of controlled nanodrug delivery to living cells in a representative, partially heated microchannel was analyzed,
using a validated computer model. The objective was to achieve uniform nanoparticle exit concentrations at a minimum microchannel
length with the aid of simple static mixers, e.g., a multi-baffle-slit or perforated injection micro-mixer. A variable wall
heat flux, which influences the local nanofluid properties and carrier-fluid velocities, was added to ensure that mixture
delivery to the living cells occurred at the required (body) temperature of 37°C. The results show that both the baffle-slit
micro-mixer and the perforated injection micro-mixer aid in decreasing the microchannel length while achieving uniform nanoparticle
exit concentrations. The injection micro-mixer not only decreases best the system’s dimension, but also reduces the system
power requirement. The baffle-slit micro-mixer also decreases the microchannel length; however, it may add to the power requirement.
The imposed wall heat flux aids in enhanced nanoparticle and base-fluid mixing as well. 相似文献
6.
Suresh Kumar S. Ashwin Clement H. Karthik R. 《Journal of Failure Analysis and Prevention》2017,17(4):780-787
Journal of Failure Analysis and Prevention - In the present work, mixed-mode stress intensity factor (SIF) of multiple cracks in a riveted lap joint has been determined, with and without the... 相似文献
7.
Wuller Charles E. Nielsen L. Carlisle Clement David M. 《IEEE transactions on nuclear science》1978,25(4):1061-1067
Cable response to X-rays is linear with incident fluence, provided the deposited charge in cable dielectrics is directly proportional to the X-ray flux. To estimate the level at which the linear region ends, we discuss three nonlinear processes that modify the deposited charge profile in a hypothetical cable model: field-limiting in vacuum gaps, ionization effects in air-filled gaps, and radiation-induced dielectric conductivity. The exact level at which limiting of the Norton driver in an elemental length of cable begins depends on the cable geometry and the X-ray source. Estimates of the onset of nonlinearities caused by field-limiting and by dielectric conductivity are found in terms of cable and source parameters. With air-filled gaps, the Norton driver is always nonlinear. In addition to limiting of the Norton drivers, the load response of a long cable may be limited because propagating currents are attenuated by the induced conductivity of the bulk of the dielectric. 相似文献
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