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The hadronic decays of the τ lepton can be used to determine the effective charge ατ(m τ 2,) for a hypothetical τ lepton with a mass in the range 0

Dressed Gluon Exponentiation (DGE) is used to calculate the thrust and the heavy-jet mass distributions in e + e - annihilation in the two-jet region. We perform a detailed analysis of power corrections, taking care of the effect of hadron masses on the measured observables. In DGE the Sudakov exponent is calculated in a renormalization-scale invariant way using renormalon resummation. Neglecting

We investigate the relation between a postulated skeleton expansion and the conformal limit of QCD. We begin by developing some consequences of an Abelian-like skeleton expansion, which allows one to disentangle running-coupling effects from the remaining skeleton coefficients. The latter are by construction renormalon free, and hence hopefully better behaved. We consider a simple ansatz for the e

We calculate the potential between two static quarks in QCD using modified boundary conditions for the perturbative expansion. Through a change of the Feynman prescription we effectively add a "sea" of gluons to the asymptotic states with energies below a given scale A. We find that the standard result for the static potential gets corrections of order A 2/Q 2 both at small and large momentum tran

The thrust distribution in e+e- annihilation is calculated exploiting its exponentiation property in the two-jet region t=1-T≪1. We present a general method (DGE) to calculate a large class of logarithmically enhanced terms, using the dispersive approach in renormalon calculus. Dressed Gluon Exponentiation is based on the fact that the exponentiation kernel is associated primarily with a single gl

We discuss how the renormalization scheme ambiguities in QCD can be fixed, when two observables are related, by requiring the coefficients in the perturbative expansion relating the two observables to have their conformal limit values, i.e., to be independent of the [Formula presented] function of the renormalized coupling. We show how the next-to-leading order BLM automatic scale-fixing method ca

We analyze the lowest spectral moments of the left-right two-point correlation function, using all known short-distance constraints and the recently updated ALEPH V-A spectral function from τ decays. This information is used to determine the low-energy couplings L10 and C87 of chiral perturbation theory and the lowest-dimensional contributions to the operator product expansion of the left-right co

We present a complete set of helicity-dependent 2 → 3 antenna functions for QCD initial- and final-state radiation. The functions are implemented in the Vincia shower Monte Carlo framework and are used to generate showers for hadron-collider processes in which helicities are explicitly sampled (and conserved) at each step of the evolution. Although not capturing the full effects of spin correlatio

Transfusion-related acute lung injury (TRALI) is one of the leading causes of transfusion-related fatalities and is characterized by the onset of acute respiratory distress within 6 hours of a blood transfusion. There are no specific therapies available and the pathogenesis remains unclear. Pre-existing inflammation is a risk factor for TRALI and neutrophils (PMNs) are considered to be the major p

Transfusion-associated circulatory overload (TACO) and Transfusion-related acute lung injury (TRALI) are syndromes of acute respiratory distress which occur within 6 hours of blood transfusion. TACO and TRALI are the leading causes of transfusion-related fatalities and specific therapies are unavailable. Diagnostically, it remains very challenging to distinguish TACO and TRALI from underlying caus

Objective: To examine the performance of ultrasound (US) for the diagnosis of gout using the presence of monosodium urate monohydrate (MSU) crystals as the gold standard. Methods: We analyzed data from the Study for Updated Gout Classification Criteria (SUGAR), a large, multicenter observational cross-sectional study of consecutive subjects with at least 1 swollen joint who conceivably may have go

During the last glacial period, proxy records throughout the Northern Hemisphere document a succession of rapid millennial-scale warming events, called Dansgaard-Oeschger (DO) events. A range of different mechanisms has been proposed that can produce similar warming in model experiments; however, the progression and ultimate trigger of the events are still unknown. Because of their fast nature, th

Probiotics should bring ‘balance’ to the intestinal microbiota by stimulating beneficial bacteria, whilst mitigating adverse ones. Balance can also be interpreted as high alpha-diversity. Contrary, Escherichia coli is often regarded as an adverse component of the resident intestinal microbiota. The aim of the present study was to implement a mouse model for in vivo screening of Lactobacillus-strai

The 1993 Ground-based Cloud Experiment on Great Dun Fell used a wide range of measurements of trace gases, aerosol particles and cloud droplets at five sites to study their sources and sinks especially those in cloud. These measurements have been interpreted using a variety of models. The conclusions add to our knowledge of air pollution, acidification of the atmosphere and the ground, eutrophicat

Single-particle analysis, performed by laser microprobe mass spectrometry and bulk analytical techniques were used to study aerosol-cloud interactions within the third field campaign of the EUROTRAC subproject 'ground-based cloud experiments' at the Great Dun Fell, Cumbria, U.K. in spring 1993. The shape of the ridge made it possible for ground-based instrumentation to sample similar parcels of ai

A technique for the characterisation of droplet aerosols is presented and theoretically evaluated. The system, which finds applications for example in the experimental study of cloud formation and cloud water chemistry, relies on a four-step process. The droplet aerosol is electrically charged in a unipolar charging unit, followed by diffusion drying of the droplets, resulting in charged particles

Based on a novel dataset of about 1150 time series, this study provides monthly economic activity estimates for 28 countries during the Great Depression. Due to their high frequency, the indices reveal that steady growth was far from universal even in the second half of the 1920s. Monetary and financial instability, agricultural crises, and labor conflict continued to plague economies around the g

The recent surge in publications on the history of knowledge may obscure the fact that there are several parallel understandings of what the field is. In this article, I discern five major historiographical directions in contemporary scholarship regarding the history of knowledge. The analytical framework that has so far attracted the most attention is the circulation of knowledge. As productive a