Article history: Received 18 September 2007 Received in revised form 27 June 2008 Accepted 21 September 2008 Available online 2 October 2008

Studying the thermoelectric effect in DNA is important for unravelling charge transport mechanisms and for developing relevant applications of DNA molecules. Here we report a study of the thermoelectric effect in single DNA molecules. By varying the molecular length and sequence, we tune the charge transport in DNA to either a hopping- or tunnelling-dominated regimes. The thermoelectric effect ...

This paper extends existing models of frequency-dependent diet selection by considering the optimal diet selection of a predator feeding upon prey populations which can be depleted but are also capable of renewal (e.g. immigration, growth, or reproduction). This model and existing models which include prey depletion, predict partial-preference and a generic diet preference for the commonest pre...

Mixed models are widely used to analyze longitudinal data. In their conventional formulation as linear mixed models (LMMs) and generalized LMMs (GLMMs), a commonly indispensable assumption in settings involving longitudinal non-Gaussian data is that the longitudinal observations from subjects are conditionally independent, given subject-specific random effects. Although conventional Gaussian...

Background and Objective: Today, opioids are used to control and relieve acute and chronic pain. However, the incidence of both tolerance and dependence phenomena for these drugs is a major problem. So, in this study, the combination effect of haloperidol and methadone on the acquisition and expression of morphine dependence and tolerance was examined.    Materials and Methods: Ninety-eight mic...

Introduction: Nicotine is the psychoactive substance responsible for establishing and maintaining smoking dependence. CYP2A6 is the primary enzyme that inactivates nicotine to cotinine .Genetic variation in CYP2A6 accounts for some of the inter-individual variability in nicotine metabolism and has been indicated to influence smoking behavior and dependence. Therefore, the aim of this study was ...

Objectives: Dependence and tolerance are major restricting factors in the clinical use of opioid analgesics. In the present study, the effects of thymoquinone, the major constituent of Nigella sativa seeds, on morphine dependence and tolerance were investigated in mice. Materials and Methods: Male adult NMRI mice were made tolerant and dependent by repeated injections of morphine (50, 50, and 7...

Abstract Background: Opium-dependence having different effects on the nervous system is a common problem, especially in the Middle East and Iran. The aim of this study is evaluating the effects of opium-dependence on visual evoked potential (VEP) in men. Methods: Thirty subjects with both chronic cigarette smoking and opium-dependence (group 1) and 30 subjects with only chronic ciga...

Abstract Background and Objective: According to the issue of dependence and tolerance in addicted patients, the inefficiency of existing treatments and the new recommendation for drug combination therapy for diseases in modern pharmacology, the present study examined the effect of methadone and valproate combination on morphine dependence and tolerance. Materials and Methods: Ninety-eight male ...