The three-loop beta-fuction of QCD with the clover action

We calculate, to 3 loops in perturbation theory, the bare $\beta$-function of QCD, formulated on the lattice with the clover fermionic action. The dependence of our result on the number of colors $N$, the number of fermionic flavors $N_f$, as well as the clover parameter $c_{SW}$, is shown explicitly. A direct outcome of our calculation is the two-loop relation between the bare coupling constant $g_0$ and the one renormalized in the MS-bar scheme. Further, we can immediately derive the three-loop correction to the relation between the lattice $\Lambda$-parameter and $g_0$, which is important in checks of asymptotic scaling. For typical values of $c_{SW}$, this correction is found to be very pronounced.Comment: 14 pages, 2 eps figure

Testing perturbation theory on the nf=0 static quark potential

The perturbative expansion of static force and potential is reanalyzed concerning its practical applicability. A well behaved perturbative prediction is given by the integration of the renormalization group equation for the coupling $\alpha_{qq}(\mu=1/r)=(C_f)^{-1} r^2 F(r)$. Since the Lambda-parameter of the \nf=0 theory is known from previous work, the perturbative prediction contains no free parameter. It is confronted with recent non-perturbative results. For $\alpha < 0.3$ where the truncation error of the perturbative expression is naively estimated to be moderate, it is really quite accurate and large ``non-perturbative terms'' are excluded.Comment: Added comment on known alpha^4 log(alpha) term (page 8), References and acknowledgemen

Two Loop Computation of the Schroedinger Functional in Lattice QCD

We compute the Schroedinger functional (SF) for the case of lattice QCD with Wilson fermions (with and without SW improvement) at two-loop order in lattice perturbation theory. This allows us to extract the three-loop beta-function in the SF-scheme. These results are required to compute the running coupling, the Lambda-parameter and quark masses by finite size techniques with negligible systematic errors. In addition our results enable the implementation of two-loop O(a) improvement in SF-simulations.Comment: 30 pages, numerical changes in eqs.(A.9), (A.10), (5.6), (5.9), (5.12) due to the revision of hep-lat/9801007v2 (Christou et al.

Schr"odinger functional at negative flavour number

The scaling of the Schr"odinger functional coupling is studied numerically and perturbatively for an SU(3) lattice gauge field coupled to an O(a) improved bosonic spinor field. This corresponds to QCD with minus two light flavours and is used as a numerically less costly test case for real QCD. A suitable algorithm is developed, and the influence of the matter fields on the continuum limit and the lattice artefacts are studied in detail.Comment: 24 pages, 7 figures, small textual change

Investing in the future - identifying participants in an educational program for middle-aged and older adults

With the aging of societies, gerontological issues have become increasingly relevant. Within health education research, however, issues related to aging remain underrepresented. It is not yet understood whether and by what means people prepare for their aging. This article seeks to identify those who invest in the future by examining the reach of the educational program ‘In anticipation of the golden years’. We studied what motivated participants to enroll, and collected demographic, psychological and social network characteristics from the 158 individuals (mean age 61.5 years) who had signed up for the program. These data were compared with data from large-scale surveys of the aging population in order to examine the representativeness of program participants. The majority of participants' motives corresponded very well with the aims of the program. Comparison of demographic, psychological and social characteristics revealed that, in general, participants enjoyed greater psychological resources than in the population, while they were less advantaged with respect to their personal situation (predominantly household composition and subjective health) and social relationships. Our findings suggest that future investment in relation to aging is a well-accepted idea that appeals to individuals who exhibit a specific combination of resources and risk factors

Limited results of group self-management education for rheumatoid arthritis patients and their partners: explanations from the patient perspective

This study aimed to identify the reasons for limited results of group self-management for RA patients and their partners from the patient perspective. Semi-structured interviews with ten male and ten female patients who had participated in group self-management with or without their partner were content analyzed with respect to motivation to participate and the effects of the program on them. The limited effects of the self-management program appear to be linked with low motivation to participate and to change health behavior. The data show that a decline in health and also stressful life events might be associated with the disappointing effects of the program. Three strategies were proposed for improving the program’s effects: (a) provide information about the program in advance to ensure that patients have appropriate expectations. (b) Enhance intrinsic motivation to change health behavior by counseling techniques. (c) Tailoring with respect to motivation and current concerns could help to form more homogeneous groups or could be the basis for a tailored online intervention

The Capacity Catalogue: Enabling Open Society Grantees to Achieve More

This digital booklet is designed to help Open Society grantees and prospective grantees in Europe strengthen their organisations.Like any for-profit company or public institution, civil society organisations must be competent in several areas to function well under pressure, and with few resources. Their capacity to do their work depends on their performance in many areas: governance, strategy, work planning, communication, fundraising, and several others. The Capacity Catalogue helps civil society organisations recognise these areas, assess how they currently perform, and find the help they need. Its aim is to help civil society leaders identify their organisations' strengths, their weaknesses, and think critically about where and how to improve. This document is a joint publication with ODS, with the support of the Open Society Initiative for Europe.Resources are included at the end

HR Del remnant anatomy using 2-D spectral data and 3-D photoionization shell models

The HR Del nova remnant was observed with the IFU-GMOS at Gemini North. The spatially resolved spectral data cube was used in the kinematic, morphological and abundance analysis of the ejecta. The line maps show a very clumpy shell with two main symmetric structures. The first one is the outer part of the shell seen in H-alpha, that forms two rings projected in the sky plane. These ring structures correspond to a closed hourglass shape, first proposed by Harman and O'Brien (2003). The equatorial emission enhancement is caused by the superimposed hourglass structures in the line of sight. The second structure seen only in the [OIII] and [NII] maps is located along the polar directions inside the hourglass structure. Abundances gradients between the polar caps and equatorial region were not found. However, the outer part of the shell seems to be less abundant in Oxygen and Nitrogen than the inner regions. Detailed 2.5D photoionization modeling of the 3D shell was performed using the mass distribution inferred from the observations and the presence of mass clumps. The resulting model grids are used to constrain the physical properties of the shell as well as the central ionizing source. A sequence of 3D clumpy models including a disk shaped ionization source is able to reproduce the ionization gradients between polar and equatorial regions of the shell. Differences between shell axial ratios in different lines can also be explained by aspherical illumination. A total shell mass of 9 x 10-4 Msun is derived from these models. We estimate that 50% to 70% of the shell mass is contained in neutral clumps with density contrast up to a factor of 30.Comment: 31 pages 12 figures 4 tables title correcte

Impact of large cutoff-effects on algorithms for improved Wilson fermions

As a feasibility study for a scaling test we investigate the behavior of algorithms for dynamical fermions in the N_f=2 Schroedinger functional at an intermediate volume of 1 fm^4. Simulations were performed using HMC with two pseudo-fermions and PHMC at lattice spacings of approximately 0.1 and 0.07 fm. We show that some algorithmic problems are due to large cutoff-effects in the spectrum of the improved Wilson-Dirac operator and disappear at the smaller lattice spacing. The problems discussed here are not expected to be specific to the Schroedinger functional.Comment: 19 pages, 12 figures, Sec. 2 extended, few references added. Accepted for publication in Comp. Phys. Com