1,797 research outputs found
Interventions for smoking cessation and reduction in individuals with schizophrenia
Background Patients with schizophrenia smoke more heavily than the general population and this contributes to their higher morbidity and mortality from smoking‐related illnesses. It remains unclear what interventions can help them to quit or reduce smoking. Objectives To evaluate the benefits and harms of different treatments for nicotine dependence in schizophrenia. Search methods We searched the Cochrane Tobacco Addiction Group Specialized Register and electronic databases including MEDLINE, EMBASE and PsycINFO from inception to April 2010. Selection criteria We included randomized trials for smoking cessation or reduction, comparing any pharmacological or non‐pharmacological intervention with placebo or with another therapeutic control in adult smokers with schizophrenia or schizoaffective disorder. Data collection and analysis Two reviewers independently assessed the eligibility and quality of trials and extracted data. Outcome measures included smoking abstinence, reduction in the amount smoked and any change in mental state. We extracted abstinence and reduction data at the end of treatment and at least six months after the intervention. We used the most rigorous definition of abstinence or reduction and biochemically validated data where available. Any reported adverse events were noted. Where appropriate, we pooled data using a random effects model. Main results We included 21 trials (11 trials of smoking cessation; four trials of smoking reduction; one trial for relapse prevention; five trials reported smoking outcomes for interventions aimed at other purposes). Seven trials compared bupropion with placebo; meta‐analysis showed that smoking cessation rates after bupropion were significantly higher than placebo at the end of treatment (seven trials, N=340; risk ratio [RR] 2.84; 95% confidence interval [CI] 1.61 to 4.99) and after six months (five trials, N=214, RR 2.78; 95% CI 1.02 to 7.58). Expired carbon monoxide (CO) level and the number of cigarettes smoked daily were significantly lower with bupropion at the end of therapy but not after six months. There were no significant differences in positive, negative and depressive symptoms between bupropion and placebo group. There was no report of major adverse event such as seizures with bupropion. Contingent reinforcement (CR) with money may increase smoking abstinence rates and reduce the level of smoking in patients with schizophrenia. However, it is uncertain whether these benefits are maintained in the longer term. There was no evidence of benefit for the few trials of other pharmacological therapies (including nicotine replacement therapy (NRT)) and psychosocial interventions in helping smokers with schizophrenia to quit or reduce smoking. Authors' conclusions Bupropion increases smoking abstinence rates in smokers with schizophrenia, without jeopardising their mental state. Bupropion may also reduce the amount these patients smoke. CR may help this group of patients to quit and reduce smoking. We failed to find convincing evidence that other interventions have a beneficial effect on smoking behaviour in schizophrenia
Antiferromagnetic spintronics
Antiferromagnetic materials could represent the future of spintronic
applications thanks to the numerous interesting features they combine: they are
robust against perturbation due to magnetic fields, produce no stray fields,
display ultrafast dynamics and are capable of generating large
magneto-transport effects. Intense research efforts over the past decade have
been invested in unraveling spin transport properties in antiferromagnetic
materials. Whether spin transport can be used to drive the antiferromagnetic
order and how subsequent variations can be detected are some of the thrilling
challenges currently being addressed. Antiferromagnetic spintronics started out
with studies on spin transfer, and has undergone a definite revival in the last
few years with the publication of pioneering articles on the use of spin-orbit
interactions in antiferromagnets. This paradigm shift offers possibilities for
radically new concepts for spin manipulation in electronics. Central to these
endeavors are the need for predictive models, relevant disruptive materials and
new experimental designs. This paper reviews the most prominent spintronic
effects described based on theoretical and experimental analysis of
antiferromagnetic materials. It also details some of the remaining bottlenecks
and suggests possible avenues for future research
How branching can change the conductance of ballistic semiconductor devices
We demonstrate that branching of the electron flow in semiconductor
nanostructures can strongly affect macroscopic transport quantities and can
significantly change their dependence on external parameters compared to the
ideal ballistic case even when the system size is much smaller than the mean
free path. In a corner-shaped ballistic device based on a GaAs/AlGaAs
two-dimensional electron gas we observe a splitting of the commensurability
peaks in the magnetoresistance curve. We show that a model which includes a
random disorder potential of the two-dimensional electron gas can account for
the random splitting of the peaks that result from the collimation of the
electron beam. The shape of the splitting depends on the particular realization
of the disorder potential. At the same time magnetic focusing peaks are largely
unaffected by the disorder potential.Comment: accepted for publication in Phys. Rev.
Current induced switching of magnetic domains to a perpendicular configuration
In a ferromagnet--normal-metal--ferromagnet trilayer, a current flowing
perpendicularly to the layers creates a torque on the magnetic moments of the
ferromagnets. When one of the contacts is superconducting, the torque not only
favors parallel or antiparallel alignment of the magnetic moments, as is the
case for two normal contacts, but can also favor a configuration where the two
moments are perpendicular. In addition, whereas the conductance for parallel
and antiparallel magnetic moments is the same, signalling the absence of giant
magnetoresistance in the usual sense, the conductance is greater in the
perpendicular configuration. Thus, a negative magnetoconductance is predicted,
in contrast with the usual giant magnetoresistance.Comment: 4 pages, 3 figures, major rewriting of the technical par
Recommended from our members
2D Visualization of the Psoriasis Transcriptome Fails to Support the Existence of Dual-Secreting IL-17A/IL-22 Th17 T Cells.
The present paradigm of psoriasis pathogenesis revolves around the IL-23/IL-17A axis. Dual-secreting Th17 T cells presumably are the predominant sources of the psoriasis phenotype-driving cytokines, IL-17A and IL-22. We thus conducted a meta-analysis of independently acquired RNA-seq psoriasis datasets to explore the relationship between the expression of IL17A and IL22. This analysis failed to support the existence of dual secreting IL-17A/IL-22 Th17 cells as a major source of these cytokines. However, variable relationships amongst the expression of psoriasis susceptibility genes and of IL17A, IL22, and IL23A were identified. Additionally, to shed light on gene expression relationships in psoriasis, we applied a machine learning nonlinear dimensionality reduction strategy (t-SNE) to display the entire psoriasis transcriptome as a 2-dimensonal image. This analysis revealed a variety of gene clusters, relevant to psoriasis pathophysiology but failed to support a relationship between IL17A and IL22. These results support existing theories on alternative sources of IL-17A and IL-22 in psoriasis such as a Th22 cells and non-T cell populations
- …