Test of the QCD vacuum with the sources in higher representations

Recent accurate measurement by G.Bali of static potentials between sources in various SU(3) representations provides a crucial test of the QCD vacuum and of different theoretical approaches to the confinement. In particular, the Casimir scaling of static potentials found for all measured distances implies a strong suppression of higher cumulants and a high accuracy of the Gaussian stochastic vacuum. Most popular models are in conflict with these measurements.Comment: LaTeX, 7 page

Casimir scaling as a test of QCD vacuum

Recent accurate measurements of static potentials between sources in various representations of the gauge group SU(3) performed by G.Bali provide a crucial test of the QCD vacuum models and different approaches to confinement. The Casimir scaling of the potential observed for all measured distances implies strong suppression of higher cumulant contributions. The consequences for the instanton vacuum model and the spectrum of the QCD string are also discussed.Comment: LaTeX, 15 pages, 1 figur

A national appraisal of haemodialysis vascular access provision in Scotland

Purpose: Published registry data demonstrate longstanding variation in the utilisation of different vascular access (VA) modalities between Scottish renal units; this may reflect different clinical processes between centres. A comprehensive appraisal was undertaken to understand the processes underpinning VA creation and maintenance across Scotland. Methods: A mixed methods approach was utilised. Fifty-two semi-structured interviews were conducted with patients and clinicians in all ten, adult and paediatric, Scottish renal units. Interview transcripts were subjected to thematic analysis. Clinical activity data were prospectively collected for six weeks, and correlated with registry data. Results: VA accounts for a large clinical workload. There was significant inter-centre variation in the utilisation of different VA modalities, and patients described frustrating, dissatisfying experiences. VA creation and maintenance pathways functioned best when nephrologists, surgeons and radiologists were co-located on the same campus with close multi-disciplinary working, protected clinical time, and proactive VA maintenance. No unit routinely measured or discussed procedure outcomes or strategic aspects of their service. Conclusions: Varied clinical outcomes reflected varied clinical processes. Optimised clinical pathways, staff education and measurement of clinical outcomes may improve VA service quality and facilitate safer, more effective, patient-centred care

Clergy work-related satisfactions in parochial ministry: the influence of personality and churchmanship

The aim of this study was to test several hypotheses that clergy work-related satisfaction could be better explained by a multidimensional rather than a unidimensional model. A sample of 1071 male stipendiary parochial clergy in the Church of England completed the Clergy Role Inventory, together with the short-form Revised Eysenck Personality Questionnaire. Factor analysis of the Clergy Role Inventory identified five separate clergy roles: Religious Instruction, Administration, Statutory Duties (conducting marriages and funerals), Pastoral Care, and Role Extension (including extra-parochial activities). Respondents also provided an indication of their predispositions on the catholic-evangelical and liberal-conservative dimensions. The significant associations of the satisfactions derived from each of the roles with the demographic, personality, and churchmanship variables were numerous, varied, and, with few exceptions, small in magnitude. Separate hierarchical regressions for each of the five roles indicated that the proportion of total variance explained by churchmanship was, in general, at least as great as that explained by personality, and was greater for three roles: Religious Instruction, Statutory Duties, and Role Extension. It was concluded that clergy satisfactions derived from different roles are not uniform and that churchmanship is at least as important as personality in accounting for clergy work satisfaction

The paracladistic approach to phylogenetic taxonomy

The inclusion of some paraphyletic groups in a temporally and taxonomically comprehensive phylogenetic classification is inevitable because cladistic methodology is incapable of excluding the possibility that a structurally (i.e., based on the branching pattern of a given cladogram) monophyletic group contains the ancestor of another group, i.e., that it is historically paraphyletic. Paracladistics is proposed as a pragmatic synthesis of phylogenetic and evolutionary taxonomy in which true monophyly is distinguished from structural monophyly with historical paraphyly, some structurally paraphyletic groups are retained in the interest of nomenclatorial continuity and stability, and both unranked and suprageneric ranked taxon names are defined phylogenetically. Ancestral groups are structurally paraphyletic or structurally monophyletic but historically paraphyletic sets of species that are believed to contain the ancestor for the most recent common ancestor of a descendent group. Historical paraphyly is determined by considering evidence of nesting in cladistic analyses, timing of first appearances in the fossil record, polarity in character evolution, and taxa that are morphologically intermediate between groups of species. The decision to name an ancestral group is based on the same criteria as the decision to name a clade. Ancestral groups are defined in the same manner as clades, except that their descendent group(s) are designated as external specifiers. Recognizing that two supposedly monophyletic, cladistically defined sister taxa can represent ancestral and descendent groups has implications for inferring their times of origination. To illustrate the advantages of the paracladistic approach to phylogenetic taxonomy, alternative paracladistic and phylogenetic classifications of the crown group families of Nuculanoidea (Mollusca, Bivalvia) are presented

Two-loop amplitudes with nested sums: Fermionic contributions to e+ e- --> q qbar g

We present the calculation of the nf-contributions to the two-loop amplitude for e+ e- --> q qbar g and give results for the full one-loop amplitude to order eps^2 in the dimensional regularization parameter. Our results agree with those recently obtained by Garland et al.. The calculation makes extensive use of an efficient method based on nested sums to calculate two-loop integrals with arbitrary powers of the propagators. The use of nested sums leads in a natural way to multiple polylogarithms with simple arguments, which allow a straightforward analytic continuation.Comment: 31 pages, a file "coefficients.h" with the results in FORM format is include