Mode fluctuations as fingerprint of chaotic and non-chaotic systems

The mode-fluctuation distribution $P(W)$ is studied for chaotic as well as for non-chaotic quantum billiards. This statistic is discussed in the broader framework of the $E(k,L)$ functions being the probability of finding $k$ energy levels in a randomly chosen interval of length $L$, and the distribution of $n(L)$, where $n(L)$ is the number of levels in such an interval, and their cumulants $c_k(L)$. It is demonstrated that the cumulants provide a possible measure for the distinction between chaotic and non-chaotic systems. The vanishing of the normalized cumulants $C_k$, $k\geq 3$, implies a Gaussian behaviour of $P(W)$, which is realized in the case of chaotic systems, whereas non-chaotic systems display non-vanishing values for these cumulants leading to a non-Gaussian behaviour of $P(W)$. For some integrable systems there exist rigorous proofs of the non-Gaussian behaviour which are also discussed. Our numerical results and the rigorous results for integrable systems suggest that a clear fingerprint of chaotic systems is provided by a Gaussian distribution of the mode-fluctuation distribution $P(W)$.Comment: 44 pages, Postscript. The figures are included in low resolution only. A full version is available at http://www.physik.uni-ulm.de/theo/qc/baecker.htm

Transient jets in V617 Sagittarii

Some of the luminous Compact Binary Supersoft X-Ray sources (CBSS) have shown indications of jets, also called satellites due to their appearance in the spectra. In V Sagittae (V Sge) stars, the galactic counterparts of the CBSS, such features have been reported only for WX Cen. If V Sge stars are indeed the analogs of CBSS, one may expect transient jet emission in other objects of this class. Spectroscopic observations of the V Sge star V617 Sgr have been made, both at high photometric state and at decline. We show that V617 Sgr presents Halpha satellites at high photometric state with velocities of +/-780 km/s. This feature confirms, once more, the CBSS nature of the V Sge stars, however the details of the spectral characteristics also suggest that the two groups of stars display some intrinsic spectroscopic differences, which are likely to be due to a selection effect related to chemical abundance.Comment: Four pages, accepted to be published as a Letter in A&

Anxiety and depression in Nepal: prevalence, comorbidity and associations

BACKGROUND: Anxiety and depression are two important contributors to the global burden of disease. In many developing countries, including Nepal, their prevalences are yet to be assessed. METHODS: A nationwide cross-sectional study was conducted among a representative sample of Nepalese adults aged 18–65 years (N = 2100), selected by multistage random cluster sampling and interviewed at home during unannounced visits. The validated questionnaires included the Hospital Anxiety and Depression Scale (HADS), to detect cases of anxiety (HADS-A), depression (HADS-D) and comorbid anxiety and depression (HADS-cAD), the Eysenck Personality Questionnaire Revised Short Form-Neuroticism (EPQRS-N), and the World Health Organization Quality of Life 8-question scale (WHOQOL-8). Logistic regression analyses were used to explore associations of caseness with four groups of variables: demographic, domicile, substance use, and behavioural and health. RESULTS: Age- and gender-adjusted point prevalences of HADS-A, HADS-D and HADS-cAD were 16.1, 4.2 and 5.9 % respectively. In a multivariate model, HADS-A was positively associated with urban residence (AOR = 1.82; p < 0.001) and neuroticism (AOR = 1.32; p < 0.001), and negatively with alcohol consumption (AOR = 0.71; p = 0.041). HADS-D was positively associated with marijuana use (AOR = 3.61; p = 0.017) and negatively with quality of life (QoL) (AOR = 0.86; p < 0.001). HADS-cAD was positively associated with widowhood (AOR = 2.71; p = 0.002), urban residence (AOR = 2.37; p = 0.001), living at altitude ≥2000 m (AOR = 2.32; p = 0.002) and neuroticism (AOR = 1.26; p < 0.001), and negatively with alcohol use (AOR = 0.56; p = 0.026) and QoL (AOR = 0.79; p < 0.001). CONCLUSION: Depression and anxiety are important mental health conditions in Nepal, and major contributors to public ill health, being very highly prevalent, comorbid and associated with psychosocial burden. They are also linked to the unique topography, habitation and social structure of the country. High prevalence coupled with the disabling nature of these disorders establishes their health-care priority and their importance in national health policy

Dynamic scaling and universality in evolution of fluctuating random networks

We found that models of evolving random networks exhibit dynamic scaling similar to scaling of growing surfaces. It is demonstrated by numerical simulations of two variants of the model in which nodes are added as well as removed [Phys. Rev. Lett. 83, 5587 (1999)]. The averaged size and connectivity of the network increase as power-laws in early times but later saturate. Saturated values and times of saturation change with paramaters controlling the local evolution of the network topology. Both saturated values and times of saturation obey also power-law dependences on controlling parameters. Scaling exponents are calculated and universal features are discussed.Comment: 7 pages, 6 figures, Europhysics Letters for

Primakoff Physics for CERN COMPASS Hadron Beam: Hadron Polarizabilities, Hybrid Mesons, Chiral Anomaly, Meson Radiative Transitions

We describe a hadron physics program attainable with a partially instrumented CERN COMPASS spectrometer, involving tracking detectors and moderate-size ECAL2/HCAL2 calorimeters. COMPASS can realize a state-of-the-art hadron beam physics program based on hadron polarizability, hybrid mesons, chiral anomaly, and meson radiative transition studies. We review here the physics motivation for this hadron beam program. We describe the beam, detector, trigger requirements, and hardware/software requirements for this program. The triggers for all this physics can be implemented for simultaneous data taking. The program is based on using a hadron beam (positive/negative pion, kaon, proton) in COMPASS.Comment: Contribution to the Proceedings of the Charles U./JINR and International U. (Dubna) CERN COMPASS Summer School, Charles University, Prague, Czech Republic, August 1997, Eds. M. Chavleishvili and M. Finger Tel Aviv U. Preprint TAUP TAUP-2473-98. 26 pages, 11 figures, late

Comorbidities of psychiatric and headache disorders in Nepal: implications from a nationwide population-based study

Background Headache disorders, anxiety and depression – the major disorders of the brain – are highly comorbid in the western world. Whether this is so in South Asia has not been investigated, but the question is of public-health importance to countries in the region. We aimed to investigate associations, and their direction(s), between headache disorders (migraine, tension-type headache [TTH] and headache on ≥15 days/month) and psychiatric manifestations (anxiety, depression and neuroticism), and how these might affect quality of life (QoL). Methods In a nationwide, cross-sectional survey of the adult Nepalese population (N = 2100), trained interviewers applied: 1) a culturally-adapted version of the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire to diagnose headache disorders; 2) a validated Nepali version of the Hospital Anxiety and Depression Scale (HADS) to detect anxiety (HADS-A), depression (HADS-D) and comorbid anxiety and depression (HADS-cAD); 3) a validated Nepali version of the Eysenck Personality Questionnaire Revised Short Form-Neuroticism (EPQRS-N); and 4) the World Health Organization Quality of Life 8-question scale (WHOQOL-8). Associations with headache types were analysed using logistic regression for psychiatric caseness and linear regression for neuroticism. Adjustments were made for age, gender, household consumption, habitat, altitude and use of alcohol and marijuana. Results HADS-A was associated with any headache (p = 0.024), most strongly headache on ≥15 days/month (AOR = 3.2) followed by migraine (AOR = 1.7). HADS-cAD was also associated with any headache (p = 0.050, more strongly among females than males [p = 0.047]) and again most strongly with headache on ≥15 days/month (AOR = 2.7), then migraine (AOR = 2.3). Likewise, neuroticism was associated with any headache (p < 0.001), most strongly with headache on ≥15 days/month (B = 1.6), followed by migraine (B = 1.3). No associations were found between HADS-D and any headache type, or between TTH and any psychiatric manifestation. Psychiatric caseness of any sort, when comorbid with migraine or TTH, aggravated the negative impact on QoL (p < 0.001). Conclusion Headache disorders are highly comorbid with anxiety and show associations with neuroticism in Nepal, with negative consequences for QoL. These findings call for reciprocal awareness, and a holistic coordinated approach to management and in the health service. Care for common headache and common psychiatric disorders should be integrated in primary care.publishedVersion© 2016 Risal et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/

Employment Effects of Publicly Financed Training Programs The East German Experience

We analyze the effectiveness of publicly financed training and retraining programs in east Germany as measured by their effects on individual re-employment probabilities after training. These are estimated by discrete hazard rate models on the basis of individual-level panel data. We account for unobserved individual heterogeneity in both the training participation and outcome equation. The latter differentiates between transitions into "stable" and "unstable" employment after the completion of a training program. Our findings are that in the first phase of the east German transition process, when the institutions delivering the training programs were being set up, there are no positive effects of training on the probability to find stable employment. For the period of September 1992 to November 1994, when the institutional structure for the programs was in place, we find positive effects of both on?the?job and off?the?job training for women, and positive effects of off?the?job training for men. --publicly financed training,evaluation studies,employment effects,sample selection,east Germany