Palatini Variational Principle for NN-Dimensional Dilaton Gravity

We consider a Palatini variation on a general $N$-Dimensional second order, torsion-free dilaton gravity action and determine the resulting equations of motion. Consistency is checked by considering the restraint imposed due to invariance of the matter action under simple coordinate transformations, and the special case of N=2 is examined. We also examine a sub-class of theories whereby a Palatini variation dynamically coincides with that of the "ordinary" Hilbert variational principle; in particular we examine a generalized Brans-Dicke theory and the associated role of conformal transformations.Comment: 16 pages, LaTe

Gauged (2,2) Sigma Models and Generalized Kahler Geometry

We gauge the (2,2) supersymmetric non-linear sigma model whose target space has bihermitian structure (g, B, J_{\pm}) with noncommuting complex structures. The bihermitian geometry is realized by a sigma model which is written in terms of (2,2) semi-chiral superfields. We discuss the moment map, from the perspective of the gauged sigma model action and from the integrability condition for a Hamiltonian vector field. We show that for a concrete example, the SU(2) x U(1) WZNW model, as well as for the sigma models with almost product structure, the moment map can be used together with the corresponding Killing vector to form an element of T+T* which lies in the eigenbundle of the generalized almost complex structure. Lastly, we discuss T-duality at the level of a (2,2) sigma model involving semi-chiral superfields and present an explicit example.Comment: 33 page

Hamiltonian BRST Quantization of the Conformal String

We present a new formulation of the tensionless string ($T= 0$) where the space-time conformal symmetry is manifest. Using a Hamiltonian BRST scheme we quantize this {\em Conformal String} and find that it has critical dimension $D=2$. This is in keeping with our classical result that the model describes massless particles in this dimension. It is also consistent with our previous results which indicate that quantized conformally symmetric tensionless strings describe a topological phase away {}from $D=2$. We reach our result by demanding nilpotency of the BRST charge and consistency with the Jacobi identities. The derivation is presented in two different ways: in operator language and using mode expansions. Careful attention is payed to regularization, a crucial ingredient in our calculations.Comment: 33pp (LaTeX), USITP-94-0

Lifshitz fermionic theories with z=2 anisotropic scaling

We construct fermionic Lagrangians with anisotropic scaling z=2, the natural counterpart of the usual z=2 Lifshitz field theories for scalar fields. We analyze the issue of chiral symmetry, construct the Noether axial currents and discuss the chiral anomaly giving explicit results for two-dimensional case. We also exploit the connection between detailed balance and the dynamics of Lifshitz theories to find different z=2 fermionic Lagrangians and construct their supersymmetric extensions.Comment: Typos corrected, comment adde

Experience of violation during the past 3 months, social capital, and self-rated health: A population-based study.

Objective: The objective was to investigate the association between experience of violation during the past 3 months and self-rated health, taking trust (social capital), economic stress, and country of birth and parents' country of birth into account. Design/setting/participants/measurements: The 2008 public health survey in Skåne is a cross-sectional study with 55% response rate. A random sample was approached using a postal questionnaire, and 28,198 persons aged 18-80 responded. Logistic regression models investigated associations between experience of violation during the past 3 months and self-rated health. Results: A 27.4% proportion of the men and 30.0% of the women reported less than good health. Less than good health was significantly higher in older age groups, among persons born outside Sweden, with low education, economic stress, low trust in other people, and experience of violation during the past 3 months. The group with experience of violation at one occasion during the past 3 months had odds ratio 1.76 (95% CI 1.57-1.97) of less than good health among men and odds ratio 1.78 (95% CI 1.62-1.96) among women, while the group with experience of violation two or more times during the past 3 months had odds ratio 4.28 (95% CI 3.36-5.44) among men and 3.54 (95% CI 2.89-4.35) among women in the final multiple analyses. Conclusions: Experience of violation during the past 3 months is significantly associated with less than good health, which is a finding with important policy implications

Long-term increase of fat mass after a four week intervention with fast food based hyper-alimentation and limitation of physical activity

<p>Abstract</p> <p>Background</p> <p>A sedentary lifestyle and increased consumption of energy dense food have become more common in many parts of the world. The aim of this study was to study long term effects on body composition after a four week intervention with fast food based hyper-alimentation and limited physical activity in young normal weight subjects.</p> <p>Methods</p> <p>Eighteen subjects, mean age 26 (6.6) years, increased their energy intake with in average 70% and physical activity were not to exceed 5000 steps/day. Body composition was measured by Dual energy x-ray (DXA) at baseline, after the intervention and after 12 months. A matched control group was also included. ANOVA and Student's paired and unpaired t-test were used.</p> <p>Results</p> <p>During the intervention body weight increased with 6.4 (2.8) kg and DXA measurements showed increases of both fat free mass and fat mass. Six months after the intervention the subjects had lost most of the weight gain, - 4.7 (3.1) kg. Twelve months after the intervention body weight had increased with 1.5 (2.4) kg compared to baseline (p = 0.018). DXA measurements at 12 months showed unchanged fat free mass compared to baseline but higher fat mass, + 1.4 (1.9) kg (p = 0.01). After 2.5 years the increase of body weight was 3.1 (4.0) kg (p = 0.01) while there was no change in controls compared to baseline, + 0.1(2.5) kg (p = 0.88).</p> <p>Conclusion</p> <p>One year after a short term intervention with increased fast food based hyper-alimentation there was an increase of fat mass but unchanged fat free mass. As the change of fat mass was larger than expected from prospective epidemiological studies and as there was no increase of body weight in controls it raises the issue whether there is a long-term effect to increase fat mass of a short period of hyper-alimentation.</p

Design and Tests of the Silicon Sensors for the ZEUS Micro Vertex Detector

To fully exploit the HERA-II upgrade,the ZEUS experiment has installed a Micro Vertex Detector (MVD) using n-type, single-sided, silicon micro-strip sensors with capacitive charge division. The sensors have a readout pitch of 120 micrometers, with five intermediate strips (20 micrometer strip pitch). The designs of the silicon sensors and of the test structures used to verify the technological parameters, are presented. Results on the electrical measurements are discussed. A total of 1123 sensors with three different geometries have been produced by Hamamatsu Photonics K.K. Irradiation tests with reactor neutrons and Co-60 photons have been performed for a small sample of sensors. The results on neutron irradiation (with a fluence of 1 x 10^{13} 1 MeV equivalent neutrons / cm^2) are well described by empirical formulae for bulk damage. The Co-60 photons (with doses up to 2.9 kGy) show the presence of generation currents in the SiO_2-Si interface, a large shift of the flatband voltage and a decrease of the hole mobility.Comment: 33 pages, 25 figures, 3 tables, accepted for publication in NIM

Electronic hand hygiene monitoring: accuracy, impact on the Hawthorne effect and efficiency

Objectives: To evaluate a type five electronic monitoring system (EMS) for hand hygiene (HH) adherence with respect to accuracy and ability to avoid the Hawthorne effect. Design: HH events were observed manually and electronically. The agreement between the two observation methods was evaluated. Continuous electronic measurement was made throughout the study. Setting: An acute 31-bed medical ward in a National Health Service trust in London, United Kingdom. Participants: Staff working or attached to the ward. Intervention: A newly developed type five EMS that can measure disinfectant dispenser usage as well as continuous movements of health workers throughout the ward with arm-length precision and analyse HH adherence was installed at the ward. Results: A total of 294 HH events were observed in five sessions by an observer previously unknown to the ward. There was concordance between HH adherence assessed by manual observer and the EMS on 84% (79.1%–89.9%) of the occasions. During the five observation sessions, the observed HH adherence increased from 24% to 76% while the EMS measurements immediately before the arrival of the observer remained constant for all sessions. Conclusion: The 84% agreement between the EMS and the manual observation suggest a high level of precision for the evaluated system. The Hawthorne effect (higher rate of HH performance) was clearly seen in the increase by a factor of three in the manually observed adherence from session to session as the health workers became more aware of them being observed. The EMS was able to avoid the Hawthorne effect when the observer was not present

Radiation hardness of CMS pixel barrel modules

Pixel detectors are used in the innermost part of the multi purpose experiments at LHC and are therefore exposed to the highest fluences of ionising radiation, which in this part of the detectors consists mainly of charged pions. The radiation hardness of all detector components has thoroughly been tested up to the fluences expected at the LHC. In case of an LHC upgrade, the fluence will be much higher and it is not yet clear how long the present pixel modules will stay operative in such a harsh environment. The aim of this study was to establish such a limit as a benchmark for other possible detector concepts considered for the upgrade. As the sensors and the readout chip are the parts most sensitive to radiation damage, samples consisting of a small pixel sensor bump-bonded to a CMS-readout chip (PSI46V2.1) have been irradiated with positive 200 MeV pions at PSI up to 6E14 Neq and with 21 GeV protons at CERN up to 5E15 Neq. After irradiation the response of the system to beta particles from a Sr-90 source was measured to characterise the charge collection efficiency of the sensor. Radiation induced changes in the readout chip were also measured. The results show that the present pixel modules can be expected to be still operational after a fluence of 2.8E15 Neq. Samples irradiated up to 5E15 Neq still see the beta particles. However, further tests are needed to confirm whether a stable operation with high particle detection efficiency is possible after such a high fluence.Comment: Contribution to the 11th European Symposium on Semiconductor Detectors June 7-11, 2009 Wildbad Kreuth, German