2,170 research outputs found

    Application of shock tubes to transonic airfoil testing at high Reynolds numbers

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    Performance analysis of a gas-driven shock tube shows that transonic airfoil flows with chord Reynolds numbers of the order of 100 million can be produced, with limitations being imposed by the structural integrity of the facility or the model. A study of flow development over a simple circular arc airfoil at zero angle of attack was carried out in a shock tube at low and intermediate Reynolds numbers to assess the testing technique. Results obtained from schlieren photography and airfoil pressure measurements show that steady transonic flows similar to those produced for the same airfoil in a wind tunnel can be generated within the available testing time in a shock tube with properly contoured test section walls

    The learning experiences of health and social care paraprofessionals on a foundation degree

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    Foundation degrees have been developed in the UK as a means of meeting the learning needs of paraprofessionals in health and social care and the services within which they work in a cost-effective fashion. Workplace learning is an intrinsic component to these degrees. Taking a socio-cultural perspective, this paper examines how the students' workplaces, life circumstances and sense of career trajectory shaped their learning experience and motivation. A small-scale evaluation study, using semi-structured interviews, focused on the learning experiences of a group of paraprofessionals enrolled in a foundation degree in health and social care. Data revealed fragmented employment patterns, underpinned by consistent vocational drives. While the study resonated with vocation, participants were ambivalent or lacked information about career progression. Workplace conditions, relationships and limited time shaped learning and coping strategies. A strategic and focused approach to student learning is required and includes attention to career pathways, workforce development strategy, the requirements of a range of stakeholders, workplace supervision and support for learning

    Measuring Family Centred Care: Working with Children and Their Parents in a Tertiary Hospital

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    Rationale and aim: Family-centred care (FCC) is widely used in paediatrics, though no rigorous evidence for it exists. A growing body of qualitative research raises concerns about FCC, and health professionals’ attitudes to it. We measured attitudes to working with children and working with parents of hospitalised children held by nurses, doctors, allied health and ancillary staff at an Australian children’s hospital, using a validated questionnaire with two scores, one for working with children, one for working with parents, and demographic characteristics, and compared responses. Method: we recruited a randomized sample, and compared means of working with children and working with parents scores, using a Wilcoxon signed rank test p<0.0001. Mean differences by categories of demographics were estimated using ANOVA and median test compared the median scores.Results: respondents gave significantly more positive scores for working with children than parents. These were influenced by level of education, whether respondents were parents themselves, if they held senior positions, had worked with children for a long time, and held a paediatric qualification. Conclusions: paediatric health professionals view working with children in a more positive light than working with parents. However, if FCC was being implemented effectively, given its empahsis on the whole family as the unit of care, there would be no difference between working with children or their parents. This quantiative study supports the increasing body of qualitative research which highlights problems with this model. In addition, this study provides a way to measure FCC

    Structural properties of epitaxial {\alpha}-U thin films on Ti, Zr, W and Nb

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    Thin layers of orthorhombic uranium ({\alpha}-U) have been grown onto buffered sapphire substrates by d.c. magnetron sputtering, resulting in the discovery of new epitaxial matches to Ti(00.1) and Zr(00.1) surfaces. These systems have been characterised by X-ray diffraction and reflectivity and the optimal deposition temperatures have been determined. More advanced structural characterisation of the known Nb(110) and W(110) buffered {\alpha}-U systems has also been carried out, showing that past reports of the domain structures of the U layers are incomplete. The ability of this low symmetry structure to form crystalline matches across a range of crystallographic templates highlights the complexity of U metal epitaxy and points naturally toward studies of the low temperature electronic properties of {\alpha}-U as a function of epitaxial strain

    ASSEMBLEIA LEGISLATIVA DO PARANÁ: a força das linhagens políticas e das relações de parentesco

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    O presente trabalho tem o objetivo de apresentar a Assembleia Legislativa do Paraná a partir das estruturas de parentesco que marcam sua história desde a primeira legislatura republicana, em 1891. Para tanto, se torna relevante a perspectiva teórico-metodológica da conexão família e política para a compreensão das relações de poder e da dinâmica das instituições no estado do Paraná. Tal mapeamento identificou que 12 famílias possuem significativa presença na ALEP, visto que o tempo de linhagem política de certos grupos demarcam mais de um século. A pesquisa valeu-se da análise prosopográfica e genealógica de deputados que tiveram mandatos entre os anos 1935 a 1962. Dentre esses, muitos sobrenomes estenderam seu poder político pelo fato de familiares continuarem acumulando mandatos parlamentares ao longo do tempo, bem por como estarem presentes desde as atividades iniciais do referido parlamento

    The Efficiency and Fidelity of Translesion Synthesis past Cisplatin and Oxaliplatin GpG Adducts by Human DNA Polymerase β

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    DNA polymerase beta (pol beta) is the only mammalian DNA polymerase identified to date that can catalyze extensive bypass of platinum-DNA adducts in vitro. Previous studies suggest that DNA synthesis by pol beta is distributive on primed single-stranded DNA and processive on gapped DNA. The data presented in this paper provide an analysis of translesion synthesis past cisplatin- and oxaliplatin-DNA adducts by pol beta functioning in both distributive and processive modes using primer extension and steady-state kinetic experiments. Translesion synthesis past Pt-DNA adducts was greater with gapped DNA templates than with single-stranded DNA templates. In the processive mode pol beta did not discriminate between cisplatin and oxaliplatin adducts, while in the distributive mode it displayed about 2-fold increased ability for translesion synthesis past oxaliplatin compared with cisplatin adducts. The differentiation between cisplatin and oxaliplatin adducts resulted from a K(m)-mediated increase in the efficiency of dCTP incorporation across from the 3'-G of oxaliplatin-GG adducts. Rates of misincorporation across platinated guanines determined by the steady-state kinetic assay were higher in reactions with primed single-stranded templates than with gapped DNA and a slight increase in the misincorporation of dTTP across from the 3'-G was found for oxaliplatin compared with cisplatin adducts

    Human prostatic Acid phosphatase: structure, function and regulation.

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    Human prostatic acid phosphatase (PAcP) is a 100 kDa glycoprotein composed of two subunits. Recent advances demonstrate that cellular PAcP (cPAcP) functions as a protein tyrosine phosphatase by dephosphorylating ErbB-2/Neu/HER-2 at the phosphotyrosine residues in prostate cancer (PCa) cells, which results in reduced tumorigenicity. Further, the interaction of cPAcP and ErbB-2 regulates androgen sensitivity of PCa cells. Knockdown of cPAcP expression allows androgen-sensitive PCa cells to develop the castration-resistant phenotype, where cells proliferate under an androgen-reduced condition. Thus, cPAcP has a significant influence on PCa cell growth. Interestingly, promoter analysis suggests that PAcP expression can be regulated by NF-κB, via a novel binding sequence in an androgen-independent manner. Further understanding of PAcP function and regulation of expression will have a significant impact on understanding PCa progression and therapy

    Probabilistic Estimation of Site Specific Fault Displacements

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    The College of the Redwoods (CR) located near Eureka, California would like to upgrade a series of existing buildings that are unfortunately located on secondary faults associated with the active Little Salmon Fault (LSF) zone. In the early 1990’s a deterministic value of the maximum dip-slip displacement that had occurred on one of these secondary faults located beneath the southeast building corner of the former library was measured to be 1.7 feet. This displacement was resolved into approximately 1.5 feet horizontal offset and 0.8 feet of vertical offset, based on the secondary fault plane dip. Geologically, it has not been possible to establish the actual dates of the occurrence of the displacements on the observed faults, therefore it was assumed that they all had occurred within the last 11,000 years. The structural engineer for the project has indicated that it was not possible to design for the observed ground displacement of 1.7 feet. This limited study was undertaken to assess the variation of ground displacements that were observed over the area of ground occupied by CR’s Administration, Science, and former Library buildings. The purpose of this study was to evaluate the reasonableness of using a deterministically determined maximum value of displacement in estimating, and designing mitigations for, the structural response, or whether a probabilistic approach could be utilized. The only data available within the limited time frame allowed for the study was from a series of trench logs made as part of a project for locating building sites on the campus in the early 1990’s. As a first step the frequency distributions of both horizontal and vertical displacements located in a volume of soil comprising the area occupied by the above buildings to a depth of 14 feet were examined. The 14 feet was the maximum depth of the trenches used to provide data for the study. Probability density functions (PDF) versus displacements were developed based on the frequency distributions. The area under the PDF curves between given displacement intervals represents the probability of occurrence (POC) of that displacement. A cumulative probability of occurrence for a displacement interval can be determined by adding the individual POC’s. Based on this it was estimated that a horizontal displacement of ≤ 1.0 foot has a probability of 89% of occurring in the next 11,000 years at the site. In contrast, a vertical displacement of ≤ 1.0 foot has a probability of 88% probability of occurrence

    Reliability and Validity of the Telephone-Based eHealth Literacy Scale Among Older Adults: Cross-Sectional Survey

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    Background: Only a handful of studies have examined reliability and validity evidence of scores produced by the 8-item eHealth literacy Scale (eHEALS) among older adults. Older adults are generally more comfortable responding to survey items when asked by a real person rather than by completing self-administered paper-and-pencil or online questionnaires. However, no studies have explored the psychometrics of this scale when administered to older adults over the telephone. Objective: The objective of our study was to examine the reliability and internal structure of eHEALS data collected from older adults aged 50 years or older responding to items over the telephone. Methods: Respondents (N=283) completed eHEALS as part of a cross-sectional landline telephone survey. Exploratory structural equation modeling (E-SEM) analyses examined model fit of eHEALS scores with 1-, 2-, and 3-factor structures. Subsequent analyses based on the partial credit model explored the internal structure of eHEALS data. Results: Compared with 1- and 2-factor models, the 3-factor eHEALS structure showed the best global E-SEM model fit indices (root mean square error of approximation=.07; comparative fit index=1.0; Tucker-Lewis index=1.0). Nonetheless, the 3 factors were highly correlated (r range .36 to .65). Item analyses revealed that eHEALS items 2 through 5 were overfit to a minor degree (mean square infit/outfit values <1.0; t statistics less than –2.0), but the internal structure of Likert scale response options functioned as expected. Overfitting eHEALS items (2-5) displayed a similar degree of information for respondents at similar points on the latent continuum. Test information curves suggested that eHEALS may capture more information about older adults at the higher end of the latent continuum (ie, those with high eHealth literacy) than at the lower end of the continuum (ie, those with low eHealth literacy). Item reliability (value=.92) and item separation (value=11.31) estimates indicated that eHEALS responses were reliable and stable. Conclusions: Results support administering eHEALS over the telephone when surveying older adults regarding their use of the Internet for health information. eHEALS scores best captured 3 factors (or subscales) to measure eHealth literacy in older adults; however, statistically significant correlations between these 3 factors suggest an overarching unidimensional structure with 3 underlying dimensions. As older adults continue to use the Internet more frequently to find and evaluate health information, it will be important to consider modifying the original eHEALS to adequately measure societal shifts in online health information seeking among aging populations.Open Access Fundin
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