198 research outputs found

    Two-Dimensional Spectroscopy of Extended Molecular Systems: Applications to Energy Transport and Relaxation in an α-Helix

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    A simulation study of the coupled dynamics of amide I and amide II vibrations in an α-helix dissolved in water shows that two-dimensional (2D) infrared spectroscopy may be used to disentangle the energy transport along the helix through each of these modes from the energy relaxation between them. Time scales for both types of processes are obtained. Using polarization-dependent 2D spectroscopy is an important ingredient in the method we propose. The method may also be applied to other two-band systems, both in the infrared (collective vibrations) and the visible (excitons) parts of the spectrum.

    The effect of specific learning difficulties on general practice written and clinical assessments

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    Background Substantial numbers of medical students and doctors have specific learning difficulties (SpLDs) and failure to accommodate their needs can disadvantage them academically. Evidence about how SpLDs affect performance during postgraduate general practice (GP) specialty training across the different licencing assessments is lacking. We aimed to investigate the performance of doctors with SpLDs across the range of licencing assessments. Methods We adopted the social model of disability as a conceptual framework arguing that problems of disability are societal and that barriers that restrict life choices for people with disabilities need to be addressed. We used a longitudinal design linking Multi-Specialty Assessment (MSRA) records from 2016 and 2017 with their Applied Knowledge Test (AKT), Clinical Skills Assessment (CSA), Recorded Consultation Assessment (RCA) and Workplace Based Assessment (WPBA) outcomes up to 2021. Multivariable logistic regression models accounting for prior attainment and demographics were used to determine the SpLD doctors' likelihood of passing licencing assessments. Results The sample included 2070 doctors, with 214 (10.34%) declaring a SpLD. Candidates declaring a SpLD were significantly less likely to pass the CSA (OR 0.43, 95% CI 0.26, 0.71, p = 0.001) but not the AKT (OR 0.96, 95% CI 0.44, 2.09, p = 0.913) or RCA (OR 0.81, 95% CI 0.35, 1.85, p = 0.615). Importantly, they were significantly more likely to have difficulties with WPBA (OR 0.28, 95% CI 0.20, 0.40, p < 0.001). When looking at licencing tests subdomains, doctors with SpLD performed significantly less well on the CSA Interpersonal Skills (B = −0.70, 95% CI −1.2, −0.19, p = 0.007) and the RCA Clinical Management Skills (B = −1.68, 95% CI −3.24, −0.13, p = 0.034). Conclusions Candidates with SpLDs encounter difficulties in multiple domains of the licencing tests and during their training. More adjustments tailored to their needs should be put in place for the applied clinical skills tests and during their training

    Síntese e caracterização de Nanocompósitos Esfoliados de Poliestireno: Hidróxido Duplo Lamelar via polimerização in situ

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    Nanocompósitos Esfoliados de Poliestireno (PS) e Hidróxido Duplo Lamelar (HDL) composto por zinco, alumínio e dodecil sulfato de sódio, como ânion interlamelar, foram sintetizados via polimerização in situ. O efeito de diferentes composições de HDL (0,5, 1, 3 e 5% em massa) foi avaliado. Os nanocompósitos obtidos foram caracterizados através de ensaios de Difração de Raios X (DRX), Espectroscopia no Infravermelho por Transformada de Fourier (FTIR), Microscopia Eletrônica de Transmissão (MET) e Análise Termogravimétrica (TGA). Os resultados obtidos através das análises de DRX e MET mostraram que todos os nanocompósitos produzidos apresentaram morfologia esfoliada. Os resultados das TGA, quando se utilizam 50% de perda de peso como ponto para comparação, apresentaram ganhos significativos de estabilidade térmica para todas as composições dos nanocompósitos em comparação ao poliestireno puro. Este comportamento possibilita uma vasta gama de aplicação destes novos materiais em diversos campos da indústria e pesquisa.</jats:p

    Design, fabrication, and characterization of new materials based on zirconia doped with mixed rare earth oxides: Review and first experimental results

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    Monazite is one of the most valuable natural resources for rare earth oxides (REOs) used as dopants with high added value in ceramic materials for extreme environments applications. The complexity of the separation process in individual REOs, due to their similar electronic configuration and physical–chemical properties, is reflected in products with high price and high environmental footprint. During last years, there was an increasing interest for using different mixtures of REOs as dopants for high temperature ceramics, in particular for ZrO2‐based thermal barrier coatings (TBCs) used in aeronautics and energy co‐generation. The use of mixed REOs may increase the working temperature of the TBCs due to the formation of tetragonal and cubic solid solutions with higher melting temperatures, avoiding grain size coarsening due to interface segregation, enhancing its ionic conductivity and sinterability. The thermal stability of the coatings may be further improved by using rare earth zirconates with perovskite or pyrochlore structures having no phase transitions before melting. Within this research framework, firstly we present a review analysis about results reported in the literature so far about the use of ZrO2 ceramics doped with mixed REOs for high temperature applications. Then, preliminary results about TBCs fabricated by electron beam evaporation starting from mixed REOs simulating the real composition as occurring in monazite source minerals are reported. This novel recipe for ZrO2‐based TBCs, if optimized, may lead to better materials with lower costs and lower environmental impact, as a result of the elimination of REOs extraction and separation in individual lanthanides. Preliminary results on the compositional, microstructure, morphological, and thermal properties of the tested materials are reported

    Candidate perceptions of the UK Recorded Consultation Assessment: cross-sectional data linkage study

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    The Recorded Consultation Assessment (RCA) was rapidly developed to replace the Clinical Skills Assessment (CSA) for UK general practice licencing during COVID-19. We aimed to evaluate candidate perceptions of the RCA and relationships with performance. We conducted a cross-sectional survey of RCA candidates with attitudinal, demographic, and free text response options, undertaking descriptive and factor analysis of quantitative data with qualitative thematic analysis of free text. Binomial regression was used to estimate associations between RCA pass, candidate characteristics and questionnaire responses. 645 of 1551 (41.6%) candidates completed a questionnaire; 364 (56.4%) responders permitted linkage with performance and demographic data. Responders and non-responders were similar in exam performance, gender and declared disability but were significantly more likely to be UK graduates (UKG) or white compared with international medical (IMG) or ethnic minority graduates. Responders were positive about the digital platform and support resources. A small overall majority regarded the RCA as a fair assessment; a larger majority reported difficulty collecting, selecting, and submitting cases or felt rushed during recording. Logistic regression showed that ethnicity (white vs minority ethnic: odds ratio [OR] 2.99,95% confidence interval [CI] 1.23, 7.30, p = 0.016), training (UK vs IMG: OR 6.88, 95% CI 2.79, 16.95, p < 0.001), and English as first language (OR 5.11, 0% CI 2.08, 12.56, p < 0.001) were associated with exam success but questionnaire subscales, consultation type submitted, or extent of trainer review were not. The RCA was broadly acceptable but experiences were variable. Candidates experienced challenges and suggested areas for improvement

    Trait phenomenological control predicts experience of mirror synaesthesia and the rubber hand illusion

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    In hypnotic responding, expectancies arising from imaginative suggestion drive striking experiential changes (e.g., hallucinations) — which are experienced as involuntary — according to a normally distributed and stable trait ability (hypnotisability). Such experiences can be triggered by implicit suggestion and occur outside the hypnotic context. In large sample studies (of 156, 404 and 353 participants), we report substantial relationships between hypnotisability and experimental measures of experiential change in mirror-sensory synaesthesia and the rubber hand illusion comparable to relationships between hypnotisability and individual hypnosis scale items. The control of phenomenology to meet expectancies arising from perceived task requirements can account for experiential change in psychological experiments

    A liquid profession: An ecological approach to the theory and knowledge that underpin the practice of public relations

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    This is a conceptual essay that explores the concept of knowledge as it relates to PR. It suggests an ecological knowledge architecture as a lens through which to understand the theories and concepts that support practice. It does so by drawing on the work of Zygmunt Bauman and his reflections on liquid modernity to inform and shape thinking and uses it as a thread to help synthesise scholarship from PR literature, knowledge and career scholarship and debates around professionalisation. It argues that by sub-dividing knowledge into explanatory, interventionist and practice principles greater clarity can be given to the know-how (functional skills) and know-that (theoretical knowledge) of PR. Additionally, by overlaying a postmodernist and liquid concept to this tripartite division of knowledge PR can be well placed to take advantage of the change in careers and capabilities necessary for work in the twenty-first century
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