Search results for " BE"
showing 10 items of 23740 documents
Ar tērauda un polipropilēna šķiedrām stiegrota fibrobetona īpašību izpēte
2015
Šajā darbā izpētīta polipropilēna šķiedru ietekme uz parastu un tērauda šķiedrām stiprinātu betonu, veicot četru punktu lieces un vienas šķiedras izvilkšanas eksperimentus. Papildus tika veikta porainības analīze. Iegūtie eksperimentālie rezultāti uzrāda ievērojamu īpašību uzlabošanos tērauda šķiedrām stiprinātam betonam, pievienojot tam polipropilēna šķiedras. Iepriekš veiktos pētījumos nav dots pārliecinošs skaidrojums procesiem, kas atbildīgi par šķiedru sinerģiju. Šī darba autors piedāvā vienkāršu izskaidrojumu mehānismam, kas atbild par paaugstinātām īpašībām tērauda un polipropilēna šķiedrām stiprinātam betonam.
An arthritogenic alphavirus uses the α1β1 integrin collagen receptor
2005
Ross River (RR) virus is an alphavirus endemic to Australia and New Guinea and is the aetiological agent of epidemic polyarthritis or RR virus disease. Here we provide evidence that RR virus uses the collagen-binding alpha1beta1 integrin as a cellular receptor. Infection could be inhibited by collagen IV and antibodies specific for the beta1 and alpha1 integrin proteins, and fibroblasts from alpha1-integrin-/- mice were less efficiently infected than wild-type fibroblasts. Soluble alpha1beta1 integrin bound immobilized RR virus, and peptides representing the alpha1beta1 integrin binding-site on collagen IV inhibited virus binding to cells. We speculate that two highly conserved regions with…
Polymorphisms at β-defensin genes and mastitis in Valle del Belice dairy sheep: a case control study
2015
Mastitis is the most common and costly pathology affecting dairy animals. The identification of genetic markers that allow the inclusion of mastitis resistance in selection programs would help to reduce the costs due to the disease and the use of antibiotics. In recent years, β-defensin genes have been studied in several domestic species due to their important role in the innate immune response. The aim of this study was to determine whether β-defensin genes variability, β-defensin 1 (SBD1) and β-defensin 2 (SBD2), could distinguish between infected cases and healthy controls in Valle del Belice dairy sheep. Somatic cell count (SCC) is a powerful tool to identify animals with intramammary i…
Monotherapy with indacaterol once daily reduces the rate of exacerbations in patients with moderate-to-severe COPD: Post-hoc pooled analysis of 6 mon…
2014
Summary Background In patients with COPD, exacerbations are associated with poor quality of life and may shorten survival. Prevention of exacerbations is, therefore, a key objective in COPD management. Indacaterol, a once-daily ultra-long-acting β 2 -agonist, has been shown to reduce exacerbations in various studies. This pooled analysis evaluated the effect of indacaterol on exacerbations versus placebo. Methods Six-month data were pooled from three randomized, double-blind, and placebo-controlled studies: indacaterol 300 μg versus placebo (1 year); indacaterol 150 μg and 300 μg versus placebo (6 months); and indacaterol 150 μg versus placebo (6 months). All treatments were administered on…
Late Jurassic (Kimmeridgian–Tithonian) stable isotopes (δ18O, δ13C) and Mg/Ca ratios: New palaeoclimate data from Helmsdale, northeast Scotland
2010
Abstract The data presented here provide the first detailed stable isotope ( δ 18 O, δ 13 C) and geochemical (Mg/Ca) investigation of Kimmeridgian–Tithonian belemnites from the Helmsdale Coast, Scotland, UK. Oxygen and carbon stable isotope values from well preserved specimens range from − 2.8 to + 0.3‰ and from − 2.3 to + 2.8‰ respectively. The oxygen isotope data are consistent with palaeotemperatures of up to 24 °C in the Early Kimmeridgian cymodoce Zone and down to 11 °C in the Mid Tithonian rotunda–fittoni Zones. These estimates are strongly supported by the Mg/Ca data, which also indicate a cooling episode (and very similar palaeotemperatures, 11–22 °C) at this time. The cooling event…
A 2600-year record of past polycyclic aromatic hydrocarbons (PAHs) deposition at Holzmaar (Eifel, Germany)
2014
Polycyclic aromatic hydrocarbons (PAHs) are a proxy for climate- and human-related historical fire activity which has rarely been used beyond 1800 AD. We explored the concentration and composition patterns of PAHs together with other proxies (charcoal, C, N, S, δ13C, δ15N, and δ34S) in a sediment core of Holzmaar as indicators of variations in climate and anthropogenic activity over the past 2600 years. The concentrations of pyrogenic PAHs remained low (< 500 ng g− 1) from the pre-Roman Iron Age (600 BC) until the first significant increases to ca. 1000–1800 ng g− 1 between 1700 and 1750 AD related to regional iron production. The highest increases in pyrogenic PAH concentrations occurred w…
Unraveling environmental histories from skeletal diaries — Advances in sclerochronology
2013
High-resolution proxy archives from aquatic settings are essential to better understand processes and mechanisms of global change. During the last decade, it has become increasingly evident that calcified tissues of bivalve mollusks and cold-water corals, in particular, can significantly increase our knowledge of seasonal to multi-decadal paleoclimate and paleoenvironmental variability in the extratropical oceans and coastal marine settings. Daily, tidal, fortnightly and annual growth patterns of periodically formed skeletal hard parts provide a means to place the proxy record in a precise temporal context. Their extreme longevity coupled with the running similarity between growth increment…
Variation in Sr uptake in the shell of the freshwater gastropod Bithynia tentaculata from Lake Arreo (northern Spain) and culture experiments
2010
The Sr uptake features in Bithynia tentaculata aragonite shells from monthly collections in Lake Arreo (northern Spain) over a two-year period are compared with those from the same species grown in culture experiments with similar waters under controlled temperature. The shell aragonite of B. tentaculata from Lake Arreo formed in isotopic equilibrium with the lake water. A comparison of the stable oxygen isotope values (δ18O) from the shells and waters allowed the selection of suitable shells for Sr uptake studies. The Sr/Ca molar ratio in B. tentaculata shells (Sr/Cashell) from the lake and from the culture experiments positively correlate with some chemical parameters like conductivity an…
Search for scalar leptoquarks in pp collisions at $\sqrt{s}$=13 TeV with the ATLAS experiment
2016
An inclusive search for a new-physics signature of lepton-jet resonances has been performed by the ATLAS experiment. Scalar leptoquarks, pair-produced in pp collisions at s √s = 13 TeV at the large hadron collider, have been considered. An integrated luminosity of 3.2 fb-1, corresponding to the full 2015 dataset was used. First (second) generation leptoquarks were sought in events with two electrons (muons) and two or more jets. The observed event yield in each channel is consistent with Standard Model background expectations. The observed (expected) lower limits on the leptoquark mass at 95% confidence level are 1100 and 1050 GeV (1160 and 1040 GeV) for first and second generation leptoqua…
Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment
2018
A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZH→ℓ+ℓ−c¯c is studied. A data set with an integrated luminosity of 36.1 fb−1 of pp collisions at √s=13TeV recorded by the ATLAS experiment at the LHC is used. The H→c¯c signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σ(pp→ZH)×B(H→c¯c) is 2.7 (3.9+2.1−1.1) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.