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In rats exposed to 400 revolutions (during 6 min and 40 sec) in rotating Noble-Collip drums essentially the same increase of the active form of hepatic glycogen phosphorylase as in animals studied 6 min and 40 sec after epinephrine (50 microgram/kg) or glucagon (100 microgram/kg), both i.v., was observed. However, in rats injured daily for 6 days, on day 7 this enzyme response was substantially blunted.  相似文献   
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This paper presents a front-end circuit for optical rotary encoders. The light pulses modulated by the encoder disc are transduced into current signals, which are pre-processed and converted into digital waveforms related to the disc angular position information. The proposed front-end circuit is compensated against temperature drifts. Digitally programmable calibration is provided to account for spreads in impinging light pulse power. Measurement results on integrated prototypes are shown, demonstrating correct operation of the front-end with an optical input power from 0.5 W to 3 W up to a signal frequency of 500 kHz in a temperature range from 0 °C to 80 °C.  相似文献   
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Objective: To determine the efficacy of a peer-led social support intervention involving support groups and telephone contacts compared with standard clinical care to enhance antiretroviral medication adherence. Design: Randomized controlled trial with follow-up. Participants were 136 HIV-positive indigent mainly African American and Puerto Rican men and women recruited from an outpatient clinic in the Bronx, New York. The 3-month intervention was delivered by other HIV-positive clinic patients trained in addressing barriers to adherence and sensitively providing appraisal, spiritual, emotional, and informational adherence-related social support. Main outcome measures: Medical chart-abstracted HIV-1 RNA viral load, antiretroviral adherence according to electronic drug monitoring and participant self-report, and social support and depressive symptomatology. All assessments conducted at baseline, 3 months, and 6 months. Results: Intent-to-treat and as-treated analyses indicated no between-conditions intervention effects on the primary outcome of HIV-1 RNA viral load or any of the secondary outcomes at immediate postintervention or follow-up. Post hoc analyses within the intervention condition indicated greater intervention exposure was associated with higher self-reported adherence, higher social support, and lower depressive symptomatology at follow-up, even after controlling for baseline adherence. Conclusion: Null findings, consistent with the limited literature on efficacious highly active antiretroviral therapy (HAART) adherence interventions, may be due to insufficient exposure to the intervention, its low intensity, or the nature of the sample-a heterogeneous HAART-experienced group of patients with high levels of substance use and multiple other competing stressors. Overall, findings highlight the need for more comprehensive and intensive efforts to battle nonadherence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The multidisciplinary nature of e-government demands a research agenda that includes issues related to social inclusion, universal accessibility, interoperability, privacy, security, and citizen participation, to name a few. Understanding the underlying cultural context, the involvement of citizens in the proposal and evaluation of services, and the promotion of quality in use are aspects that need special consideration in the development of systems to support government. This paper provides an outline for a process model for promoting the identification and specification of accessible e-government services with the participation of the interested parties. A socially shared perspective is adopted toward the comprehension of the involved problems and the elaboration of potential solutions. The proposed model is a result of practice in the domain, using organizational semiotics artifacts to stimulate participation and discussion.  相似文献   
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Canister integrity and radionuclides retention is of prime importance for assessing the long term safety of nuclear waste stored in engineered geologic depositories. A comparative investigation of the interaction of uranyl ion with three different mineral surfaces has thus been undertaken in order to point out the influence of surface composition on the adsorption mechanism(s). Periodic DFT calculations using plane waves basis sets with the GGA formalism were performed on the TiO2(110), Al(OH)3(001) and Ni(111) surfaces. This study has clearly shown that three parameters play an important role in the uranyl adsorption mechanism: the solvent (H2O) distribution at the interface, the nature of the adsorption site and finally, the surface atoms’ protonation state.  相似文献   
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