1,081 research outputs found
(g0, g1, …, gk)-trees and unary OL systems
No full textAbstractIn this paper we extend the notion of (2, 3)-trees and AVL trees to (g0, g1,…, gk)-trees and (g1, g2,…,gk)-AVL trees, respectively, where 1⩽g0<g1<g2<…<gk. Complete characterization of these two classes of trees in terms of their generators g0, g1,…, gk is given and the connection between (g0, g1,… gk)-trees and unary OL systems is mentioned
Patient enablement requires physician empathy: a cross-sectional study of general practice consultations in areas of high and low socioeconomic deprivation in Scotland
Get PDF<b>Background</b> Patient 'enablement' is a term closely aligned with 'empowerment' and its measurement in a general practice consultation has been operationalised in the widely used patient enablement instrument (PEI), a patient-rated measure of consultation outcome. However, there is limited knowledge regarding the factors that influence enablement, particularly the effect of socio-economic deprivation. The aim of the study is to assess the factors influencing patient enablement in GP consultations in areas of high and low deprivation.<p></p>
<b>Methods</b> A questionnaire study was carried out on 3,044 patients attending 26 GPs (16 in areas of high socio-economic deprivation and 10 in low deprivation areas, in the west of Scotland). Patient expectation (confidence that the doctor would be able to help) was recorded prior to the consultation. PEI, GP empathy (measured by the CARE Measure), and a range of other measures and variables were recorded after the consultation. Data analysis employed multi-level modelling and multivariate analyses with the PEI as the dependant variable.<p></p>
<b>Results</b> Although numerous variables showed a univariate association with patient enablement, only four factors were independently predictive after multilevel multivariate analysis; patients with multimorbidity of 3 or more long-term conditions (reflecting poor chronic general health), and those consulting about a long-standing problem had reduced enablement scores in both affluent and deprived areas. In deprived areas, emotional distress (GHQ-caseness) had an additional negative effect on enablement. Perceived GP empathy had a positive effect on enablement in both affluent and deprived areas. Maximal patient enablement was never found with low empathy.<p></p>
<b>Conclusions</b> Although other factors influence patient enablement, the patients' perceptions of the doctors' empathy is of key importance in patient enablement in general practice consultations in both high and low deprivation settings
GROWTH AND STRUCTURAL CHARACTERISTICS OF SEMICONDUCTOR SEMIMETAL SUPERLATTICES - CDTE-BI, PBTE-BI, SNTE-SB
No full textThis work was supported under the NSF—MRL program through the Materials Research Center of Northwestern University (Grant No. DMR82-16972) and by the Office of Naval
Research (Grant No. N00014-82-K-0598)
The onset of large-scale turbulence in the interstellar medium of spiral galaxies
No full textDFG thanks the European Research Council (ADG-2011 ECOGAL), and Brazilian agencies CAPES (3400-13-1) and FAPESP (no.2011/12909-8) for financial support. IB acknowledges the European Research Council (ADG-2011 ECOGAL) for financial support. GK acknowledges support from FAPESP (grants no. 2013/04073-2 and 2013/18815-0).Turbulence is ubiquitous in the interstellar medium (ISM) of the Milky Way and other spiral galaxies. The energy source for this turbulence has been much debated with many possible origins proposed. The universality of turbulence, its reported large-scale driving, and that it occurs also in starless molecular clouds, challenges models invoking any stellar source. A more general process is needed to explain the observations. In this work, we study the role of galactic spiral arms. This is accomplished by means of three-dimensional hydrodynamical simulations which follow the dynamical evolution of interstellar diffuse clouds (similar to 100 cm-3) interacting with the gravitational potential field of the spiral pattern. We find that the tidal effects of the arm's potential on the cloud result in internal vorticity, fragmentation and hydrodynamical instabilities. The triggered turbulence results in large-scale driving, on sizes of the ISM inhomogeneities, i.e. as large as similar to 100 pc, and efficiencies in converting potential energy into turbulence in the range similar to 10-25 per cent per arm crossing. This efficiency is much higher than those found in previous models. The statistics of the turbulence in our simulations are strikingly similar to the observed power spectrum and Larson scaling relations of molecular clouds and the general ISM. The dependence found from different models indicate that the ISM turbulence is mainly related to local spiral arm properties, such as its mass density and width. This correlation seems in agreement with recent high angular resolution observations of spiral galaxies, e.g. M51 and M33.Peer reviewe
Experimental studies on isolated supersonic air-intake models of a typical air-breathing launch vehicle
No full textThe performance of two supersonic air-intake configurations, S1 and S2, has been extensively analyzed through qualitative and quantitative measurements at Mach numbers in the range 1.8 to 3.0. The exit area of the intake was varied during the tests using a butterfly valve, which was controlled using a PC. The performance of S2 was found to be comparable with that of a standard supersonic intake, with characteristic features of supercritical and subcritical behavior, whereas S1 configuration did not indicate any critical condition. The critical condition for S2 was found to occur when the exit area was about 1.24 times the throat area at M = 3.0. The measured total pressure recovery with S2 was found to be marginally higher than that for S1, whereas the mass flow rate through the intake showed considerable improvement (e.g., 11 percent at M = 3.0 and 19 percent at M = 2.0 at maximum pressure recovery condition). Similar improvements were found with the S2 configuration at other Mach numbers also. It is proposed that an Intake Performance Index (product of the pressure recovery and mass flow efficiencies), as a function of the back-pressure, may be used to compare the efficiencies of different intake configurations. (Author
PRECISION MEASUREMENT OF THE IONIZATION ENERGY OF THE STATE OF MOLECULAR HYDROGEN.
No full textAuthor Institution: ETH Zurich, Laboratorium fur Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Zurich, SwitzerlandThe ionization energy of the state of ortho H has been determined at a precision of 1.2~MHz by near-infrared laser spectroscopy. The measurement was performed by first exciting molecular hydrogen from the state to the state in a resonant two-photon process via the state and then measuring the frequency of the transition between the state and the 56p~ Rydberg state belonging to the series converging on the ground state of ortho H. The ionization energy of the state was obtained by adding this frequency to the binding energy of the 56p~ Rydberg state which has been determined previously by millimeter-wave spectroscopy and multichannel quantum-defect theory \textbf{121} (23), 11810 (2004).} \textbf{150}, 51 (2011).}. For the measurement we used a homebuilt pulsed NIR laser with Fourier-transform-limited linewidth and adjustable pulse duration. To reach the desired accuracy, systematic errors originating from ac and dc Stark shifts, from pressure shifts, and from the frequency shifts and chirps accompanying the generation of the NIR laser pulses were quantified. The ionization energy of the state will be compared with earlier results \textbf{93} (4), 2289 (1990).} \textbf{108} (7-9), 827 (2010).}. New attempts of measuring the binding energy of the state will also be mentioned
Identification and Visualization of Functionally Important Domains and Residues in Herpes Simplex Virus Glycoprotein K(gK) Using a Combination of Phylogenetics and Protein Modeling
Get PDF© 2019, The Author(s). Alphaherpesviruses are a subfamily of herpesviruses that include the significant human pathogens herpes simplex viruses (HSV) and varicella zoster virus (VZV). Glycoprotein K (gK), conserved in all alphaherpesviruses, is a multi-membrane spanning virion glycoprotein essential for virus entry into neuronal axons, virion assembly, and pathogenesis. Despite these critical functions, little is known about which gK domains and residues are most important for maintaining these functions across all alphaherpesviruses. Herein, we employed phylogenetic and structural analyses including the use of a novel model for evolutionary rate variation across residues to predict conserved gK functional domains. We found marked heterogeneity in the evolutionary rate at the level of both individual residues and domains, presumably as a result of varying selective constraints. To clarify the potential role of conserved sequence features, we predicted the structures of several gK orthologs. Congruent with our phylogenetic analysis, slowly evolving residues were identified at potentially structurally significant positions across domains. We found that using a quantitative measure of amino acid rate variation combined with molecular modeling we were able to identify amino acids predicted to be critical for gK protein structure/function. This analysis yields targets for the design of anti-herpesvirus therapeutic strategies across all alphaherpesvirus species that would be absent from more traditional analyses of conservation
On Type IIA AdS3 solutions and massive GK geometries
No full textWe give necessary and sufficient conditions for warped AdS3 (and Mink3) solutions of Type II supergravities to preserve N= (2, 0) supersymmetry, in terms of geometric conditions on their internal space M7. Such solutions possess a canonical ten-dimensional Killing vector that can be either time-like or null. In this work we classify the null case in massive Type IIA supergravity which necessitates that M7 decomposes as a circle fibration over a six-dimensional base with orthogonal SU(2)-structure containing a complex four-manifold. We narrow our focus to solutions for which M7 becomes T2 fibred over a foliation of a Kähler manifold over an interval. We find a class of solutions which are the massive Type IIA version of GK geometries and present an extremal problem which computes the central charge of the solution using just topology. Finally, we present geometric conditions for AdS3 solutions to preserve arbitrary extended chiral supersymmetry. © 2022, The Author(s)
Regional regulation of transcription in the chicken genome
No full textAbstract Background Over the past years, the relationship between gene transcription and chromosomal location has been studied in a number of different vertebrate genomes. Regional differences in gene expression have been found in several different species. The chicken genome, as the closest sequenced genome relative to mammals, is an important resource for investigating regional effects on transcription in birds and studying the regional dynamics of chromosome evolution by comparative analysis. Results We used gene expression data to survey eight chicken tissues and create transcriptome maps for all chicken chromosomes. The results reveal the presence of two distinct types of chromosomal regions characterized by clusters of highly or lowly expressed genes. Furthermore, these regions correlate highly with a number of genome characteristics. Regions with clusters of highly expressed genes have higher gene densities, shorter genes, shorter average intron and higher GC content compared to regions with clusters of lowly expressed genes. A comparative analysis between the chicken and human transcriptome maps constructed using similar panels of tissues suggests that the regions with clusters of highly expressed genes are relatively conserved between the two genomes. Conclusions Our results revealed the presence of a higher order organization of the chicken genome that affects gene expression, confirming similar observations in other species. These results will aid in the further understanding of the regional dynamics of chromosome evolution. The microarray data used in this analysis have been submitted to NCBI GEO database under accession number GSE17108. The reviewer access link is: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?token=tjwjpscyceqawjk&acc=GSE17108</p
Novel mutations involving βI-, βIIA-, or βIVB-tubulin isotypes with functional resemblance to βIII-tubulin in breast cancer
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