Showing 4411–4424 of 4,998 results for "A. Vasiliev"

Journals 2017 EN

Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at $$\sqrt{s}=$$ s = 0.9, 7, and 8 TeV

S. Acharya · D. Adamová · Jonatan Adolfsson +1024 more

We present the charged-particle multiplicity distributions over a wide pseudorapidity range (\(-\,3.4<\eta <5.0\)) for pp collisions at \(\sqrt{s}= 0.9, 7\), and 8 TeV at the LHC. Results are based on information from the Silicon Pixel Detector and the Forward Multiplicity Detector of ALICE, extending the pseudorapidity coverage of the earlier publications and the high-multiplicity reach. The measurements are compared to results from the CMS experiment and to PYTHIA, PHOJET and EPOS LHC event generators, as well as IP-Glasma calculations.

Springer Science+Business Media
Conference Proceedings 2017 EN

The QUIC Transport Protocol

Adam Langley · Alistair Riddoch · Alyssa Wilk +18 more
Not Specified
Journals 2017 EN

Membrane lipid rafts are disturbed in the response of rat skeletal muscle to short-term disuse

Alexey M. Petrov · В. В. Кравцова · Vladimir V. Matchkov +5 more

Marked loss of skeletal muscle mass occurs under various conditions of disuse, but the molecular and cellular mechanisms leading to atrophy are not completely understood. We investigate early molecular events that might play a role in skeletal muscle remodeling during mechanical unloading (disuse). The effects of acute (6–12 h) hindlimb suspension on the soleus muscles from adult rats were examined. The integrity of plasma membrane lipid rafts was tested utilizing cholera toxin B subunit or fluorescent sterols. In addition, resting intracellular Ca 2+ level was analyzed. Acute disuse disturbed the plasma membrane lipid-ordered phase throughout the sarcolemma and was more pronounced in junctional membrane regions. Ouabain (1 µM), which specifically inhibits the Na-K-ATPase α2 isozyme in rodent skeletal muscles, produced similar lipid raft changes in control muscles but was ineffective in suspended muscles, which showed an initial loss of α2 Na-K-ATPase activity. Lipid rafts were able to recover with cholesterol supplementation, suggesting that disturbance results from cholesterol loss. Repetitive nerve stimulation also restores lipid rafts, specifically in the junctional sarcolemma region. Disuse locally lowered the resting intracellular Ca 2+ concentration only near the neuromuscular junction of muscle fibers. Our results provide evidence to suggest that the ordering of lipid rafts strongly depends on motor nerve input and may involve interactions with the α2 Na-K-ATPase. Lipid raft disturbance, accompanied by intracellular Ca 2+ dysregulation, is among the earliest remodeling events induced by skeletal muscle disuse.

American Physical Society
Journals 2017 EN

Human APP Gene Expression Alters Active Zone Distribution and Spontaneous Neurotransmitter Release at the Drosophila Larval Neuromuscular Junction

Ekaterina A. Saburova · Alexander N. Vasiliev · Violetta V. Kravtsova +5 more

This study provides further insight into the molecular mechanisms that control neurotransmitter release. Experiments were performed on larval neuromuscular junctions of transgenic Drosophila melanogaster lines with different levels of human amyloid precursor protein (APP) production. To express human genes in motor neurons of Drosophila, the UAS-GAL4 system was used. Human APP gene expression increased the number of synaptic boutons per neuromuscular junction. The total number of active zones, detected by Bruchpilot protein puncta distribution, remained unchanged; however, the average number of active zones per bouton decreased. These disturbances were accompanied by a decrease in frequency of miniature excitatory junction potentials without alteration in random nature of spontaneous quantal release. Similar structural and functional changes were observed with co-overexpression of human APP and β-secretase genes. In Drosophila line with expression of human amyloid-β42 peptide itself, parameters analyzed did not differ from controls, suggesting the specificity of APP effects. These results confirm the involvement of APP in synaptogenesis and provide evidence to suggest that human APP overexpression specifically disturbs the structural and functional organization of active zone and results in altered Bruchpilot distribution and lowered probability of spontaneous neurotransmitter release.

e-Marefa
Journals 2017 EN

Metabolic pathways and genes identified by RNA-seq analysis of barley near-isogenic lines differing by allelic state of the Black lemma and pericarp (Blp) gene

Anastasiya Y. Glagoleva · Nikolay A. Shmakov · O. Y. Shoeva +5 more

Background Some plant species have ‘melanin-like’ black seed pigmentation. However, the chemical and genetic nature of this ‘melanin-like’ black pigment have not yet been fully explored due to its complex structure and ability to withstand almost all solvents. Nevertheless, identification of genetic networks participating in trait formation is key to understanding metabolic processes involved in the expression of ‘melanin-like’ black seed pigmentation. The aim of the current study was to identify differentially expressed genes (DEGs) in barley near-isogenic lines (NILs) differing by allelic state of the Blp (black lemma and pericarp ) locus. Results RNA-seq analysis of six libraries (three replicates for each line) was performed. A total of 957 genome fragments had statistically significant changes in expression levels between lines BLP and BW, with 632 fragments having increased expression levels in line BLP and 325 genome fragments having decreased expression. Among identified DEGs, 191 genes were recognized as participating in known pathways. Among these were metabolic pathways including ‘suberin monomer biosynthesis’, ‘diterpene phytoalexins precursors biosynthesis’, ‘cutin biosynthesis’, ‘cuticular wax biosynthesis’, and ‘phenylpropanoid biosynthesis, initial reactions’. Differential expression was confirmed by real-time PCR analysis of selected genes. Conclusions Metabolic pathways and genes presumably associated with black lemma and pericarp colour as well as Blp -associated resistance to oxidative stress and pathogens, were revealed. We suggest that the black pigmentation of lemmas and pericarps is related to increased level of phenolic compounds and their oxidation. The effect of functional Blp on the synthesis of ferulic acid and other phenolic compounds can explain the increased antioxidant capacity and biotic and abiotic stress tolerance of black-grained cereals. Their drought tolerance and resistance to diseases affecting the spike may also be related to cuticular wax biosynthesis. In addition, upregulated synthesis of phytoalexins, suberin and universal stress protein (USP) in lemmas and pericarps of the Blp carriers may contribute to their increased disease resistance. Further description of the DEGs haplotypes and study of their association with physiological characteristics may be useful for future application in barley pre-breeding. Electronic supplementary material The online version of this article (doi: 10.1186/s12870-017-1124-1) contains supplementary material, which is available to authorized users.

BioMed Central
Journals 2017 EN

Suboptimal control of lipid levels: results from the non-interventional Centralized Pan-Russian Survey of the Undertreatment of Hypercholesterolemia II (CEPHEUS II)

S. А. Boytsov · Наталья Анатольевна Логунова · Yua Khomitskaya +77 more

Background Elevated levels of low-density lipoprotein cholesterol (LDL-C) and glycosylated hemoglobin (HbA1c) are risk factors for cardiovascular complications. This study evaluated LDL-C goal attainment in Russian clinical practice among patients with moderate to very high cardiovascular risk. The study also assessed LDL-C goal attainment in patients prescribed lipid-lowering therapy for primary compared with secondary cardiovascular disease (CVD) prevention, predictors of LDL-C goal attainment, and the proportion of individuals with diabetes mellitus who achieved HbA1c < 7%. Methods The Centralized Pan-Russian Survey on the Undertreatment of Hypercholesterolemia in Russia II (CEPHEUS II) was a multicenter, non-interventional, cross-sectional study conducted in the Russian Federation from September 2014 to November 2015. Participants were aged ≥ 18 years, were receiving a stable dose of lipid-lowering medication and had a moderate to very high cardiovascular risk. The primary variable was the proportion of patients reaching LDL-C goals established by the Fifth Joint European Task Force guidelines. Secondary analyses used McNemar and χ 2 tests. Results Data from 2703 patients were analyzed; 91.2% had a very high cardiovascular risk and 24.0% had been diagnosed with diabetes mellitus. Overall, 17.4% of patients (95% confidence interval [CI] 15.9–18.8%) achieved LDL-C goals. Investigators estimated this proportion at 21.8% (95% CI 20.3–23.4%). LDL-C goals were achieved by more patients in the primary CVD prevention subgroup than in the secondary CVD prevention subgroup (19.7% vs 16.1%, p = 0.017). Patient-related factors associated with a decreased likelihood of achieving LDL-C goals included having ischemic heart disease or a family history of premature coronary heart disease, forgetting to take hypercholesterolemia treatment or considering it acceptable to miss prescribed doses more than once per week, and dissatisfaction with or concern about lipid-lowering therapy. Overall, 367/593 (61.9%) patients with diabetes mellitus and interpretable HbA1c results achieved HbA1c < 7%. Conclusions Hypercholesterolemia management is suboptimal in patients with moderate to very high cardiovascular risk in Russian clinical practice. Substantial opportunity remains to improve treatment target attainment and reduce the risk of cardiovascular complications. Lipid-modifying strategies may need to be intensified to reduce CVD risk in this setting. Trial registration ClinicalTrials.gov: NCT02230241 (registered 26 August 2014) Electronic supplementary material The online version of this article (10.1186/s12933-017-0641-4) contains supplementary material, which is available to authorized users.

BioMed Central
Journals 2017 EN

Quantum reflection of antihydrogen from a liquid helium film

P. -P. Crépin · E. A. Kupriyanova · R. Guérout +5 more

We study the quantum reflection of ultracold antihydrogen atoms bouncing onthe surface of a liquid helium film. The Casimir-Polder potential and quantumreflection are calculated for different thicknesses of the film supported bydifferent substrates. Antihydrogen can be protected from anni- hilation for aslong as 1.3s on a bulk of liquid 4He, and 1.7s for liquid 3He. These largelifetimes open interesting perspectives for spectroscopic measurements of thefree fall acceleration of antihydrogen. Variation of the scattering length withthe thickness of a film of helium shows interferences which we interpretthrough a Liouville transformation of the quantum reflection problem.

Institute of Physics
Journals 2017 EN

High-performance RF-sputtered Bi-substituted iron garnet thin films with almost in-plane magnetization

Mohammad NurEAlam · Mikhail Vasiliev · Kamal Alameh

Bismuth-substituted iron garnet thin films of high quality are prepared by using RF magnetron sputtering technique in pure argon (Ar) plasma. All the developed garnet films show high magneto-optic (MO) response after being optimally annealed across the visible range wavelengths. The garnet films display almost in-plane magnetization component with adequate Faraday rotation and relatively low optical absorption over a wide spectral range of frequencies from visible to the infrared. These garnet-type thin films demonstrate excellent MO properties together with very low coercive field of about 30 Oe, and can be used in a wide range of magneto optical applications, especially in magneto-plasmonic/magneto-photonic crystal based microdevices.

Optica Publishing Group