Negative Wigner function at telecommunication wavelength from homodyne detection

Quantum states of light having a Wigner function with negative values represent a key resource in quantum communication and quantum information processing. Here, we present the generation of such a state at the telecommunication wavelength of 1550nm. The state is generated by means of photon subtraction from a weakly squeezed vacuum state and is heralded by the `click' of a single photon counter. Balanced homodyne detection is applied to reconstruct the Wigner function, also yielding the state's photon number distribution. The heralding photons are frequency up-converted to 532nm to allow for the use of a room-temperature (silicon) avalanche photo diode. The Wigner function reads W(0,0)=-0.063 +/- 0.004 at the origin of phase space, which certifies negativity with more than 15 standard deviations

Relationship between activity in human primary motor cortex during action observation and the mirror neuron system

The attenuation of the beta cortical oscillations during action observation has been interpreted as evidence of a mirror neuron system (MNS) in humans. Here we investigated the modulation of beta cortical oscillations with the viewpoint of an observed action. We asked subjects to observe videos of an actor making a variety of arm movements. We show that when subjects were observing arm movements there was a significant modulation of beta oscillations overlying left and right sensorimotor cortices. This pattern of attenuation was driven by the side of the screen on which the observed movement occurred and not by the hand that was observed moving. These results are discussed in terms of the firing patterns of mirror neurons in F5 which have been reported to have similar properties

Conceptual Challenges of a Tentative Model of Stress-Induced Depression

Extent: 2p.Bernhard Baun

New developments in the management of major depressive disorder and generalized anxiety disorder: role of quetiapine

Quetiapine has demonstrated efficacy in schizophrenia, bipolar disorder and in the treatment of specific symptom clusters such as agitation and sleep problems in mood disorders. In this review, randomized controlled studies demonstrating efficacy, safety and tolerability of quetiapine in major depressive disorder (MDD) and general anxiety disorder (GAD) are evaluated. The results show that quetiapine monotherapy and quetiapine augmentation of antidepressant treatment in MDD and GAD are efficacious for short-term and maintenance treatment at a dose range between 50 and 300 mg/day. Quetiapine appears to have a specific but overall mild side-effect profile, though, some adverse effects such as sedation and somnolence may lead to withdrawal from treatment in some patients. Overall, the available evidence suggests that there is a significant role for quetiapine in the treatment of MDD and GAD

The association of psychological stress and health related quality of life among patients with stroke and hypertension in Gaza Strip

BACKGROUND: The study was performed to investigate the association of psychological stress and quality of life (QOL) among patients with the cardiovascular disease (CVD) of hypertension plus stroke or hypertension only. METHODS: The WHOQOL-BREF questionnaire was applied to 112 hypertensive patients with hypertension plus stroke and 224 hypertensive patients without stroke. Psychological stress was assessed with SCL-90. Means scale scores were compared using student-t-test and predictors of QOL were calculated with covariance analysis. RESULTS: Patients with stroke had a significant lower QOL than patients without stroke and a significantly higher level of stress (p < 0.01). In analyses of covariance psychological stress was significantly correlated to all domains of QOL among non-stroke patients. The same psychological and sociodemographic factors showed little impact on the stroke patients in these multivariable analyses. In these models psychological stress had a significant impact on the global domain of QOL among stroke patients. Income and gender were the only sociodemographic factors being significantly associated with the physical (education) and social (gender) domains of QOL in stroke patients. CONCLUSION: Psychological stress was strongly correlated with all domains of QOL in patients without stroke and was only partly associated with QOL among patients with stroke. Future studies should investigate if psychological stress is a factor suitable for educational and psychological interventions aiming at stress reduction in CVD patients which might substantially contribute to better health related quality of life in these patients

A KLT-like construction for multi-Regge amplitudes

Inspired by the calculational steps originally performed by Kawai, Lewellen and Tye, we decompose scattering amplitudes with single-valued coefficients obtained in the multi-Regge-limit of N=4 super-Yang-Mills theory into products of scattering amplitudes with multi-valued coefficients. We consider the simplest non-trivial situation: the six-point remainder function complementing the Bern-Dixon-Smirnov ansatz for multi-loop amplitudes. Utilizing inverse Mellin transformations, all single-valued amplitude components can indeed be decomposed into multi-valued amplitude components. Although the final expression is very similar in structure to the Kawai-Lewellen-Tye construction, moving away from the highly symmetric string scenario comes with several imponderabilities, some of which become more pronounced when considering more than six external legs in the remainder function.Comment: 39 pages, 11 figures, 3 appendice

Astrocytic tumour necrosis factor underlies neuron function in cognition

Pro-inflammatory cytokines have been demonstrated to have a diverse range of actions on the functioning of the CNS, and in particular learning and memory behaviours. Details of the mechanisms of action of cytokines are still to be determined. Purpose: This study uses immunohistochemistry techniques (IHC) to investigate cellular changes present in the hippocampal formation as a result of up-regulation of astrocyte-produced tumour necrosis factor (TNF)α (GFAP-TNFα+/+), prior to onset of behavioural deficits. These findings are compared directly to the hippocampal formation of a TNFα knock-out model (TNFα-/-) in which marked alterations in learning and memory are observed at the same time-point (12 wks) and to age-match wild-type mice (WT). This time period is of critical importance for further elucidating the role of TNFα in hippocampal dependent learning and memory. Methods: Hippocampi from TNFα-/-, GFAP-TNFα+/+ and WT (n = 5) were subjected to indirect IHC for the analysis of TNFα levels and distribution in regions CA1, CA3 and the dentate gyrus (DG). Results: In GFAP-TNFα+/+ there was a demonstrated accumulation of TNFα in hippocampal neurons prior to the onset of hippocampal-dependent behavioural deficits. GFAP-TNFα+/+ mice also showed a significant increase in TNFα in regions CA3 and the DG (p = <0.05) when compared to WT and TNFα-/- mice. WT mice demonstrated immunoreactivity of TNFα in regions CA1 and the DG. Conclusion: These findings suggest that astrocyte-produced TNFα is essential for normal development and functioning of the CA1 region of the hippocampus in cognitive processes. However, an overproduction of astrocytic TNFα accumulates in the neurons of the CA3 and DG regions and likely produces functional deficits, as seen in 6 months plus mice, through these regions