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Carbonyl oxides ("Criegee intermediates"), formed in the ozonolysis of alkenes, are key species in tropospheric oxidation of organic molecules and their decomposition provides a non-photolytic source of OH in the atmosphere (Johns...
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Carbonyl oxides ("Criegee intermediates"), formed in the ozonolysis of alkenes, are key species in tropospheric oxidation of organic molecules and their decomposition provides a non-photolytic source of OH in the atmosphere (Johnson and Marston, Chem. Soc. Rev., 2008, 37, 699, Harrison et al., Sci. Total Environ., 2006, 360, 5, G?b et al., Nature, 1985, 316, 535, ref. 1–3). Recently it was shown that small Criegee intermediates, C.I.'s, react far more rapidly with SO_2 than typically represented in tropospheric models, (Welz, Science, 2012, 335, 204, ref. 4) which suggested that carbonyl oxides could have a substantial influence on the atmospheric oxidation of SO_2. Oxidation of SO_2 is the main atmospheric source of sulphuric acid (H_2SO_4), which is a critical contributor to aerosol formation, although questions remain about the fundamental nucleation mechanism (Sipil? et al., Science, 2010, 327, 1243, Metzger et al., Proc. Natl. Acad. Sci. U. S. A., 2010 107, 6646, Kirkby et al., Nature, 2011, 476, 429, ref. 5–7). Non-absorbing atmospheric aerosols, by scattering incoming solar radiation and acting as cloud condensation nuclei, have a cooling effect on climate (Intergovernmental Panel on Climate Change (IPCC), Climate Change 2007: The Physical Science Basis, Cambridge University Press, 2007, ref. 8). Here we explore the effect of the Criegees on atmospheric chemistry, and demonstrate that ozonolysis of alkenes via the reaction of Criegee intermediates potentially has a large impact on atmospheric sulphuric acid concentrations and consequently the first steps in aerosol production. Reactions of Criegee intermediates with SO_2 will compete with and in places dominate over the reaction of OH with SO_2 (the only other known gas-phase source of H_2SO_4) in many areas of the Earth's surface. In the case that the products of Criegee intermediate reactions predominantly result in H_2SO_4 formation, modelled particle nucleation rates can be substantially increased by the improved experimentally obtained estimates of the rate coefficients of Criegee intermediate reactions. Using both regional and global scale modelling, we show that this enhancement is likely to be highly variable spatially with local hot-spots in e.g. urban outflows. This conclusion is however contingent on a number of remaining uncertainties in Criegee intermediate chemistry.
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We propose a universal transformation from a many-boson state to a corresponding many-fermion state in the lowest-Landau-level approximation of rotating many-body systems, inspired by the Laughlin wave function and by the Jain com...
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We propose a universal transformation from a many-boson state to a corresponding many-fermion state in the lowest-Landau-level approximation of rotating many-body systems, inspired by the Laughlin wave function and by the Jain composite-fermion construction. We employ the exact-diagonalization technique for finding the many-body states. The overlap between the transformed boson ground state and the true fermion ground state is calculated in order to measure the quality of the transformation. For very small and high angular momenta, the overlap is typically above 90%. For intermediate angular momenta, mixing between states complicates the picture and leads to small ground-state overlaps at some angular momenta
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Avitinib (AC0010) is a third generation inhibitor of the EGFR (epidermal growth factor receptor) that was permitted parallel phase I clinical trials in the US and in 2014. It is estimated to enter in market within two years. In th...
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Avitinib (AC0010) is a third generation inhibitor of the EGFR (epidermal growth factor receptor) that was permitted parallel phase I clinical trials in the US and in 2014. It is estimated to enter in market within two years. In the current study, eight in vitro metabolites were detected and their chemical structures were postulated. The main in vitro phase-I metabolic reaction was N-oxidation in piperazine moiety. The generation of reactive metabolites in avitinib metabolism was investigated using rat liver microsomes while adding capturing agents, viz potassium cyanide for reactive iminium intermediates, GSH for iminoquinones and methoxylamine for aldehyde forming stable adducts which are identifiable by LC-MS/MS. Ten reactive intermediates (four iminoquinones, three iminium and three aldehydes) were characterized. The three capturing agents used resulted in proposing four different bioactivation pathways. Upon literature examination, no former articles were found for avitinib metabolism including the produced reactive metabolites. (C) 2018 Elsevier B.V. All rights reserved.
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We consider a set of equations governing the behavior of a polymer melt which is modeled as a viscoelastic fluid possessing a natural, or stress-free state. The natural configuration is characterized through a symmetric, proper or...
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We consider a set of equations governing the behavior of a polymer melt which is modeled as a viscoelastic fluid possessing a natural, or stress-free state. The natural configuration is characterized through a symmetric, proper orthogonal intermediate deformation tensor, analogous to the left CauchyGreen deformation tensor in continuum mechanics. This tensor is required to satisfy an evolution equation. It is shown that the constraint that the intermediate tensor be proper orthogonal is satisfied provided that its initial value satisfies this constraint. Local existence and uniqueness of solutions to the initial boundary value problem of the resulting viscoelastic fluid system are established. It is also shown that the local solutions can be extended globally provided that the data are small enough.
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Olmutinib (Olita (TM)) is an orally bioavailable third generation epidermal growth factor receptor tyrosine kinase inhibitor. Olmutinib was approved in South Korea in May 2016 for the treatment of patients suffering from locally a...
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Olmutinib (Olita (TM)) is an orally bioavailable third generation epidermal growth factor receptor tyrosine kinase inhibitor. Olmutinib was approved in South Korea in May 2016 for the treatment of patients suffering from locally advanced or metastatic epidermal growth factor receptor T790M mutation-positive non-small cell lung cancer. Reactive olmutinib intermediates may be responsible for the severe side effects associated with the treatment. However, literature review revealed no previous reports on the structural identification of reactive olmutinib metabolites. In this work, the formation of reactive olmutinib metabolites in rat liver microsomes was investigated. Methoxylamine, glutathione, and potassium cyanide were used as capturing agents for aldehyde, iminoquinones, and iminium intermediates, respectively. The stable complexes formed were identified using liquid chromatography-tandem mass spectrometry. The major phase I metabolic pathway observed in vitro was hydroxylation of the piperazine ring. Seven potential reactive intermediates were characterized, including three iminium ions, three iminoquinones, and one aldehyde. Based on the findings, various bioactivation pathways were postulated. Hence, identifying the reactive intermediates of olmutinib that may be the cause of severe side effects can provide new insights, leading to improved treatments for patients.
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BACKGROUND. To validate and further improve the stratification of intermediate risk prostate cancer into favorable and unfavorable subgroups for patients undergoing radical prostatectomy.
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This article offers an overview of the development of the interdisciplinary study of the interrelations of the arts and media during the past one-hundred years. From a focus on the binary relations of literature and the visual art...
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This article offers an overview of the development of the interdisciplinary study of the interrelations of the arts and media during the past one-hundred years. From a focus on the binary relations of literature and the visual arts, music, and film these investigations turned into what came to be called “Interarts Studies” with a new tendency to include the interrelations of non-verbal arts and also to study configurations of a decidedly non-artistic nature. In the 1990s this would lead to the reconception of the arts as well as the applied arts and some non-artistic genres as media and their interrelations as intermediality. Simultaneously there began full-fledged attempts to construct a theoretical foundation for the study of intermediality (and transmediality) as a humanistic field, emphasizing media combination, intermedial reference, and intermedial transposition, especially adaptation. This article highlights developments in the German- and English-language discourse on these matters.
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In-situ observations of a moderately strong midlatitude sporadic-E layer show a separation in altitude between distinct sublayers composed of Fe+, Mg+, and NO+. From these observations it is possible to estimate the zonal wind fie...
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In-situ observations of a moderately strong midlatitude sporadic-E layer show a separation in altitude between distinct sublayers composed of Fe+, Mg+, and NO+. From these observations it is possible to estimate the zonal wind field consistent with diffusive equilibrium near the altitude of the layer. The amplitude of the zonal wind necessary to sustain the layer against diffusive effects is less than 10 mis, and the vertical wavelength is less than 10 km. [References: 12]
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This research aims to study the sera evaluation of the interference between maternal derived antibodies and IBD vaccines which are given lately. This research experienced a group of chicks taken from old aged breeders and another ...
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This research aims to study the sera evaluation of the interference between maternal derived antibodies and IBD vaccines which are given lately. This research experienced a group of chicks taken from old aged breeders and another young ones. These were divided into groups, each one contains 30 chicks. These groups were given (Intermediate and Intermediate plus) IBD vaccines when They were 21 day. Before vaccination The MDA were examined as well as the levels of the antibodies which were produced fromthe vaccination. There were found that the late Gumboro vaccination would risk the Birds by Disease, There we also found That the intermediate plus vaccination would stimulate higher immune respone than the intermediate one, but it will cause a great damage in Bursa tissues.
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Low-temperature transport has been studied in steady and pulsed magnetic field on a single crystal of SmB6. Measurements in the range of intrinsic conduction allowed us to determine the indirect gap E-g approximate to 20 meV and m...
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Low-temperature transport has been studied in steady and pulsed magnetic field on a single crystal of SmB6. Measurements in the range of intrinsic conduction allowed us to determine the indirect gap E-g approximate to 20 meV and microscopic parameters of carriers. The results obtained in the region of extrinsic conduction are discussed within the Kikoin-Mishchenko polaron-exciton model of charge fluctuations with short-range excitonic states E-ex approximate to 3.5 meV, R-ex approximate to 6 Angstrom. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 8]
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