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Tau lepton production in ep collisions at HERA

The production of tau leptons in ep collisions is investigated using data recorded by the H1 detector at HERA in the period 1994-2000. Tau leptons are identified by detecting their decay products, using leptonic and hadronic decay modes. The cross section for the production of tau lepton pairs is measured for the first time at HERA. Furthermore, a search for events with an energetic isolated tau l

Clarithromycin and prednisolone inhibit cytokine production in chronic rhinosinusitis

OBJECTIVES: Long-term, low-dose macrolide therapy is effective in the treatment of chronic rhinosinusitis. The mechanism of its anti-inflammatory effect and how this differs from corticosteroids remains unclear. The effect of clarithromycin and prednisolone on interleukin-5, interleukin-8, and granulocyte-macrophage colony-stimulating factor production by cultured chronic sinusitis nasal mucosa wa

Precautionary defaults - A new strategy for chemical risk management

In order to give adequate support to risk managers, new risk assessment methods should be developed that are (1) scientifically sound, (2) simplified, and (3) suited for precautionary risk management. In this Perspective we propose that the notion of a precautionary default can be a useful tool in the development of such methods. A precautionary default is a cautious or pessimistic assumption that

Frequency of anal sphincter rupture at delivery in Sweden and Finland--result of difference in manual help to the baby's head

BACKGROUND: Anal sphincter rupture is a serious complication of vaginal delivery and almost half the affected women have persistent defecatory symptoms despite adequate primary repair. During the past decade, the incidence of anal sphincter ruptures has been increasing in Sweden and is currently estimated to occur in 2.5% of vaginal deliveries. The aim of the study was to report the frequency of a

A comprehensive and compact n-heptane oxidation model derived using chemical lumping

A detailed reaction mechanism for n-heptane oxidation has been compiled and subsequently simplified. The model is based on a kinetic model for C1-C4 fuel oxidation of Hoyermann et al. [Phys. Chem. Chem. Phys., 2004, 6, 3824] and a detailed mechanism for n-heptane oxidation developed by Curran et al. [Combust. Flame, 1998, 114, 149]. The generated mechanism is kept compact by limiting the applicati

Variations in binding of mammalian fibrinogens to streptococci groups A, B, C, E, G and to Staphylococcus aureus

Twenty-eight beta-hemolytic streptococci of groups A, B, E, G and Streptococcus equisimilis as well as four Staphylococcus aureus strains were tested for their ability to bind fibrinogen preparations from different animal species: homo, baboon, rabbit, rat, guinea-pig, dog, horse, pig, cow and sheep. The patterns of binding indicated differences in the structures of the bacterial fibrinogen recept

Quadruples of Ge dots grown on patterned Si surfaces

In this paper, we present the results of Ge deposition on a pre-pattemed Si surface. By partially overgrowing nanometer-sized electron beam-induced carbon deposits, faceted pits form at the Si surface and well-defined arrays of self-assembled Ge dots can be grown site selectively in and around those. Typically, four closely spaced Ge islands are formed by preferential nucleation around the pits. B

A probabilistic model for the 5k+1 problem and related maps

We construct a probabilistic model which “mimics” the behaviour of a certain number-theoretical algorithm. This model involves study of a binary tree with randomly labelled edges, such that the labels have different distributions, depending on their directions. A number of properties of this tree are rigorously studied. As an application, this study could suggest what one could expect in the origi

A remote sensing-based primary production model for grassland biomes

That data from polar orbiting satellites have detected a widespread increase in photosynthetic activity over the last 20 years in the grasslands of the Sahel is justifies investigating its role in the tropical carbon cycle. But this task is undermined because ground data that are generally used to support the use of primary production models elsewhere are lacking. In this paper, we profile a Light

Is there a need for rescreening of patients treated for genital chlamydial infections?

The present communication reviews reasons to perform rescreening of chlamydia-infected persons. It brings up difficulties to differentiate between relapse and reinfection. Studies on follow-up of chlamydia-positive cases after therapy are reviewed. It also highlights reasons for therapeutic failure, like compliance, pharmacological factors, including poor bioavailability, wrong dose regimens, lack

Monolithic Integrated Oscillators - Phase Noise Analysis and Inductor Modeling

This doctoral dissertation studies voltage controlled oscillators (VCOs) that operate at low supply voltages. Due to smaller transistor sizes and lower supply voltage ratings with every new CMOS technology, voltage headroom is diminishing. Therefore, new ways to build VCOs and quadrature VCOs (QVCOs) have been sought to overcome this smaller headroom, while still maintaining the high performance o

The use of implantable cardioverter defibrillators in Iceland: a retrospective population based study

BACKGROUND: Indications for implantable cardioverter defibrillator (ICD) implantation have expanded considerably in recent years, resulting in steadily growing numbers of ICD recipients worldwide. The aim of this study was to review the overall experience with ICDs in Iceland. METHODS: This was a retrospective single centre study set at the University Hospital in Iceland. Data on all ICD implantat

The structure of sitting-atop complexes of metalloporphyrins studied by theoretical methods

The metallation of tetrapyrroles is believed to proceed via a sitting-atop (SAT) complex, in which some of the pyrrole nitrogen atoms are still protonated and the metal ion resides above the ring plane. No crystal structure of such a complex has been presented, but NMR and extended X-ray absorption fine structure (EXAFS) data has been reported for Cu2+ in acetonitrile. We have used density functio

Respiratory symptoms and lung function in 30-year-old individuals with alpha-1-antitrypsin deficiency.

Introduction: Individuals with severe alpha-1-antitrypsin (AAT) deficiency have a well-known risk of developing emphysema but it is not known at which age the first symptoms occur and lung function declines. The aim of this study was to examine the prevalence of smoking, respiratory symptoms and lung function at the age of 30 in AAT-deficient individuals (PiZ and PiSZ) identified by neonatal scree