668 research outputs found
QCD corrections to longitudinal spin asymmetries in -boson production at RHIC
The polarized antiquark distributions in the proton can be measured by
studying spin asymmetries in vector boson production in longitudinally
polarized proton-proton collisions. The STAR and PHENIX experiments at BNL RHIC
have reported first observations of single spin asymmetries in
-production most recently. We compute the QCD corrections to single and
double spin asymmetries, taking account of the leptonic decay of the
boson and of restrictions on the kinematical acceptance of the detectors. The
QCD corrections have only a small impact on the asymmetries, such that a
reliable extraction of the polarized antiquark distributions can be envisaged
once more precise measurements are made.Comment: LaTeX, 12 pages, typos corrected, references adde
Endoscopic endodontic microsurgery: 2-year evaluation of healing and functionality.
This prospective clinical study aimed to evaluate the benefits of the endoscope as an aid to root-end management, and to assess the treatment outcome during 2 years following surgery. Forty-three endodontic surgical procedures in 30 patients were performed with the aid of an endoscope and followed for a period of 2 years. Radiographic criteria and clinical evaluation were used to assess the outcome. All cases were evaluated in terms of healing and functionality. 91.1% and 90.7% of the teeth evaluated after 1 and 2 years, respectively, were classified as successful. We found no statistically significant differences for both healing and functionality between the 1- and 2-year evaluations. No difference related to tooth type or tooth location was found at the 2-year follow-up. Fisher's exact test was used to statistically assess the difference between successful and unsuccessful cases for each of the variables considered. The endoscope can be an aid for endodontic surgical procedures in terms of both periapical healing and functionality up to 2 years follow-up
Variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets in type 2 diabetes in general practice and characteristics associated with risk factor control.
Aims
To identify population, general practitioner, and practice characteristics associated with the achievement of HbA1c, blood pressure and LDL cholesterol targets, and to describe variation in the achievement of risk factor control.
Methods
We conducted a crossâsectional survey of 9342 people with type 2 diabetes, 281 general practitioners and 77 general practices in Norway. Missing values (7.4%) were imputed using multiple imputation by chained equations. We used threeâlevel logistic regression with the achievement of HbA1c, blood pressure and LDL cholesterol targets as dependent variables, and factors related to population, general practitioners, and practices as independent variables.
Results
Treatment targets were achieved for HbA1c in 64%, blood pressure in 50%, and LDL cholesterol in 52% of people with type 2 diabetes, and 17% met all three targets. There was substantial heterogeneity in target achievement among general practitioners and among practices; the estimated proportion of a GPs diabetes population at target was 55â73% (10â90 percentiles) for HbA1c, 36â63% for blood pressure, and 47â57% for LDL cholesterol targets. The models explained 11%, 5% and 14%, respectively, of the total variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets. Use among general practitioners of a structured diabetes form was associated with 23% higher odds of achieving the HbA1c target (odds ratio 1.23, 95% confidence interval (CI) 1.02â1.47) and 17% higher odds of achieving the LDL cholesterol target (odds ratio 1.17, 95% CI 1.01â1.35).
Conclusions
Clinical diabetes management is difficult, and few people meet all three risk factor control targets. The proportion of people reaching target varied among general practitioners and practices. Several population, general practitioner and practice characteristics only explained a small part of the total variation. The use of a structured diabetes form is recommended.publishedVersio
Regularization in quantum field theory from the causal point of view
The causal approach to perturbative quantum field theory is presented in
detail, which goes back to a seminal work by Henri Epstein and Vladimir Jurko
Glaser in 1973. Causal perturbation theory is a mathematically rigorous
approach to renormalization theory, which makes it possible to put the
theoretical setup of perturbative quantum field theory on a sound mathematical
basis. Epstein and Glaser solved this problem for a special class of
distributions, the time-ordered products, that fulfill a causality condition,
which itself is a basic requirement in axiomatic quantum field theory. In their
original work, Epstein and Glaser studied only theories involving scalar
particles. In this review, the extension of the method to theories with higher
spin, including gravity, is presented. Furthermore, specific examples are
presented in order to highlight the technical differences between the causal
method and other regularization methods, like, e.g. dimensional regularization.Comment: 75 pages, 8 figures, style file included, some comments and
references adde
Guided tissue regeneration using a barrier membrane in endodontic surgery
Endodontic surgery aims at the resolution of a periapical inflammatory process by surgical access followed by enucleation of the lesion and root-end filling to curb any potentially noxious agent within the physical confines of the affected root. Guided bone regeneration could be associated to endodontic surgery aiming to enhance periradicular tissue regeneration. The objective of this paper was to review the scientific literature about guided bone regeneration in endodontic surgery, evaluating the effects on periapical lesion healing process. The included articles are classified considering the anatomical characteristics of the lesion. Fourteen articles were included in the review after abstract and title selection. Eight articles were on studies on lesions affecting only the periapical region (three about through-and-through lesions) while six were about the treatment of apico-marginal lesions. On the basis of the currently available literature, there is a low scientific evidence of a benefit related. to the use of guided bone regeneration procedure in endodontic surgery
Dominant negative effect of cytoplasmic actin isoproteins on cardiomyocyte cytoarchitecture and function.
Hudson '70 : gravity observations 62.9SÌ - 57.5NÌ along 150WÌ
To provide geoidal topography over the world oceans, a radar altimeter carried by earth satellite is planned. Ground truth calibration will be provided by a grid comprised of the equatorial belt and meridional traverses along the 30°W and 150°W meridians. Ground truth topography is derived from gravity values measured along these traverses. This report presents the free air gravity values and the computed free air anomalies obtained from 62.9°S to 57.5°N along the 150°W meridian.Supported by the Office of Naval Research under Contract N00014-66-C0241; NR 083-004
Fate of charge order in overdoped La-based cuprates
In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in LaSrCuO and LaEuSrCuO. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes. Long-range temperature-dependent stripe order is only found below optimal doping. At higher doping, short-range temperature-independent correlations are present up to the highest doping measured. This transformation is distinct from and preempts the pseudogap critical doping. We argue that the doping and temperature-independent short-range correlations originate from unresolved electronâphonon coupling that broadly peaks at the stripe ordering vector. In LaSrCuO, long-range static stripe order vanishes around optimal doping and we discuss both quantum critical and crossover scenarios
Identification of Colletotrichum species associated with anthracnose disease of coffee in Vietnam
Colletotrichum gloeosporioides, C. acutatum, C. capsici and C. boninense associated with anthracnose disease on coffee (Coffea spp.) in Vietnam were identified based on morphology and DNA analysis. Phylogenetic analysis of DNA sequences from the internal transcribed spacer region of nuclear rDNA and a portion of mitochondrial small subunit rRNA were concordant and allowed good separation of the taxa. We found several Colletotrichum isolates of unknown species and their taxonomic position remains unresolved. The majority of Vietnamese isolates belonged to C. gloeosporioides and they grouped together with the coffee berry disease (CBD) fungus, C. kahawae. However, C. kahawae could be distinguished from the Vietnamese C. gloeosporioides isolates based on ammonium tartrate utilization, growth rate and pathogenictity. C. gloeosporioides isolates were more pathogenic on detached green berries than isolates of the other species, i.e. C. acutatum, C capsici and C. boninense. Some of the C. gloeosporioides isolates produced slightly sunken lesion on green berries resembling CBD symptoms but it did not destroy the bean. We did not find any evidence of the presence of C. kahawae in Vietnam
Uniaxial pressure induced stripe order rotation in La1.88Sr0.12CuO4
Static stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult. From a strong-coupling perspective, transverse stripe fluctuations are realized in the form of dynamic âkinksââsideways shifting stripe sections. Here, we show how modest uniaxial pressure tuning reorganizes directional kink alignment. Our starting point is La1.88Sr0.12CuO4 where transverse kink ordering results in a rotation of stripe order away from the crystal axis. Application of mild uniaxial pressure changes the ordering pattern and pins the stripe order to the crystal axis. This reordering occurs at a much weaker pressure than that to detwin the stripe domains and suggests a rather weak transverse stripe stiffness. Weak spatial stiffness and transverse quantum fluctuations are likely key prerequisites for stripes to coexist with superconductivity
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