Medial prefrontal cortex and anterior cingulate cortex in the generation of alpha activity induced by transcendental meditation: a magnetoencephalographic study.

Previous EEG studies have shown that transcendental meditation (TM) increases frontal and central alpha activity. The present study was aimed at identifying the source of this alpha activity using magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously on eight TM practitioners before, during, and after TM. The magnetic field potentials corresponding to TM-induced alpha activities on EEG recordings were extracted, and we attempted to localize the dipole sources using the multiple signal classification (MUSIC) algorithm, equivalent current dipole source analysis, and the multiple spatio-temporal dipole model. Since the dipoles were mapped to both the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC), it is suggested that the mPFC and ACC play an important role in brain activity induced by TM.</p

Self-pulsation and excitability of blue-violet InGaN lasers

This article gives a review of our latest results on the self-pulsation and excitability properties of blue-violet lasers. A number of investigations of the phenomena in InGaN lasers with different designs are described. The bifurcations, which are the origin of the phenomena, are identified and the effects of the lasers parameters on device dynamics are discussed. It is shown how different laser structures can be used to control device behaviour and the dependence of self-pulsation and excitability behaviour on laser geometry is discussed. Finally, agreement between the results of numerical calculations and experimental measurements on self-pulsation is demonstrated

Self-pulsation in an InGaN laser - theory and experiment -

Room-temperature operation of self-pulsating InGaN lasers was obtained at a wavelength of 395 nm. The laser structure consists of a multiquantum-well InGaN active layer and a p-type InGaN single-quantum-well saturable absorber. The frequency range of the self-pulsation was from 1.6 to 2.9 GHz. The experimental results were well explained with our theoretical analysis. We found that features of the saturable absorber strongly affect the self-pulsation. Influence of device and material parameters on the laser dynamics was also investigated

The Frizzled 3 gene is associated with methamphetamine psychosis in the Japanese population

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Cancer risk in patients with chronic obstructive pulmonary disease

Purpose: The goal of this study was to compare the risk of developing cancer between patients with or without chronic obstructive pulmonary disease (COPD), and to assess the role of gender as well as the use of respiratory medication on the risk of developing lung cancer in COPD patients.Patients and methods: We used the UK-based General Practice Research Database to conduct a follow-up study with a nested case-control analysis. We identified all patients with a first-time COPD diagnosis aged 40–79 years between 1995 and 2005 and a matched COPD-free comparison group. We then identified all patients who received an incident cancer diagnosis during follow-up. Results: Among 35,772 COPD patients and 35,772 COPD-free patients, we identified 4506 patients with an incident cancer diagnosis, of whom 2585 (57.4%) had a previous COPD diagnosis, yielding a crude incidence rate ratio of 1.64 (95% CI 1.55–1.74). The increased risk was mainly driven by a high lung cancer risk among COPD patients, while other cancers not associated with smoking were not statistically significantly associated with an altered COPD risk. In the nested case-control analysis, the odds ratio (OR) for lung cancer associated with COPD was higher for women (OR 5.26, 95% CI 3.64–7.61) than for men (OR 2.10, 95% CI 1.70–2.60). In the nested case-control analysis, none of the respiratory drugs were associated with a substantially altered risk of developing lung cancer among COPD patients.Conclusion: Our findings provide further evidence that COPD is associated with an elevated lung cancer risk, and that women with COPD may be more susceptible to developing lung cancer than men. Overall, respiratory medication did not have an influence on cancer risk