882 resultados para Royal Observatory, Cape of Good Hope.
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The morphologies and structures for the thin film of blend systems consisting of two asymmetric polystyrene-block-polybutadiene (SB) diblock copolymers induced by annealing in the vapor of different solvents, namely, cyclohexane, benzene, and heptane, which have different selectivity or preferential affinity for a certain block, were investigated by tapping mode atomic force microscopy (AFM) and transmission electron microscopy (TEM). The results revealed that even a slight preferential affinity of good solvent for one block would strongly alter the morphology of the blend thin film.
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Two rare earth heteropolymetalates K9GdW10O36 and K-11[Gd(PW11O39)(2)] have been synthesized and characterized by IR and elemental analysis. Their stability has been studied by TG - DTA. The TG - DTA analysis show that both complexes are of good thermal stability. Their relaxivity in D2O is 6.89 and 5.27 mmol(-1).s(-1) respectively. Interaction with BSA has also been investigated. The results indicate that the two rare earth heteropolymetalate may be potential contrast agent for MRI.
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Self-assembled monolayers(SAMs) of trichlorogermanyl propanoic acid derivatives on hydroxylated silicon substrates are prepared for the first time. Contact angle measurement, ellipsometry and X-ray photoelectron spectrometry(XPS) are used to characterize these SAMs, It is demonstrated that a quasi-2D network is formed on the surface of the substrate after molecules adsorbed on it. The molecular chains have certain tilt angles to the substrate surface, The wettabilities of the SAMs are various,because the molecules adsorbed and liquids used in the experiments are different. It can be concluded that trichlorogermanes have similar self-assembly behavior as trichlorosilanes, Four SAMs are studied together: they are acid, ethyl, butyl and hexyl surfaces whose results are of good consistency.
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Eastman-AQ 55D was coated onto a carbon fiber microelectrode surface, and the resulting modified electrodes exhibited high stability. Substantial improvement in the stability was observed as a result of good adhesion and the strong binding of large hydrophobic cations of Eastman AQ 55D. The electrode reaction of meldola blue bound in the polymer film showed a reversible, one-electron transfer process. The effects of solution pH and influence of supporting electrolyte on the modified carbon fiber microelectrode are discussed. The diffusion coefficient of meldola blue in the AQ polymer film determined by chronoamperometry is 2.3 x 10(-18) cm(2) s(-1), and the heterogeneous rate constant of meldola blue at the AQ polymer film/electrode determined by normal pulse voltammetry is 3.97 x 10(-3) cms(-1).
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Srinivasan, A., King, R. D. and Bain, M.E. (2003) An Empirical Study of the Use of Relevance Information in Inductive Logic Programming. Journal of Machine Learning Research. 4(Jul):369-383
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Urquhart, C., Turner, J., Durbin, J. & Ryan, J. (2006). Evaluating the contribution of the clinical librarian to a multidisciplinary team. Library and Information Research, 30(94), 30-43. Sponsorship: NHS Trusts in North Wales
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Durbin, J., Urquhart, C. & Yeoman, A. (2003). Evaluation of resources to support production of high quality health information for patients and the public. Final report for NHS Research Outputs Programme. Aberystwyth: Department of Information Studies, University of Wales Aberystwyth. Sponsorship: Department of Health
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Urquhart, C., Spink, S. & Thomas, R., Assessing training and professional development needs of library staff. Report for National Library of Health. (2005). Aberystwyth: Department of Information Studies, University of Wales Aberystwyth Sponsorship: National Library for Health (NHS Information Authority)
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The purpose of this Report is to inform discussions, policy formulation, and strategic planning on teacher education in Ireland. The research gives priority to initial teacher education (ITE) and induction, their interface, and implications for the continuum of teacher education, including continuing professional development (CPD). The study involved a two-pronged approach: a narrative review of recent and relevant literature and a cross-national review of teacher education policies in nine countries, namely, Ireland, Northern Ireland, Scotland, England, Finland, USA, Poland, Singapore and New Zealand. Adopting a broad, balanced and comprehensive understanding of the role of the contemporary teacher, it provides a framework for developing quality teacher education in Ireland. The Report incorporates exemplars of good practice and notes their implementation challenges for the Irish context. Chapter One provides a framework for conceptualising quality teacher education and the continuum. Key features that emerge from the literature are discussed: teachers¿ practice, quality teaching, the professional life-cycle, teacher learning and relationships. With more specific reference to the continuum, Chapter Two overviews initial teacher education, induction, learning outcomes and accreditation in the selected countries, including Ireland. Key features of policy in the various countries are summarised. Individual country profiles, incorporating descriptions of socio-political, teaching and teacher education contexts, are further detailed in Appendix A. Chapter Three analyses relevant literature on initial teacher education, induction, learning outcomes/professional standards and accreditation. Along with previous chapters it provides the basis for recommendations for teacher education that are presented in Chapter Four. Chapter Four draws together the findings emerging from the cross-national review in terms of the contemporary context of teacher education in Ireland and identifies key challenges and possible lines of policy development as well as recommendations for the Teaching Council and other teacher education stakeholders. Each generation has an opportunity to provide the vision and resources for renewing teacher education in light of ambitious social, economic and educational aspirations to meet perceived societal and education challenges (as occurred in the 1970s). Despite the publication of two key reviews of initial teacher education a number of years ago, there is considerable scope for further reform of teacher education. However, significant changes have occurred to teacher education course provision and content over the last 100 years. In this report, we have stressed the need for, and called for investment in, greater system and programme coherence, mentoring to support assisted practice, knowledge integration, critical reflective practice, inquiry and the development of vibrant partnerships between higher education institutions and schools as the basis for teacher education reform across the continuum. This Executive Summary presents the Report¿s context, key findings and recommendations emerging from the analysis.
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Wireless Inertial Measurement Units (WIMUs) combine motion sensing, processing & communications functionsin a single device. Data gathered using these sensors has the potential to be converted into high quality motion data. By outfitting a subject with multiple WIMUs full motion data can begathered. With a potential cost of ownership several orders of magnitude less than traditional camera based motion capture, WIMU systems have potential to be crucially important in supplementing or replacing traditional motion capture and opening up entirely new application areas and potential markets particularly in the rehabilitative, sports & at-home healthcarespaces. Currently WIMUs are underutilized in these areas. A major barrier to adoption is perceived complexity. Sample rates, sensor types & dynamic sensor ranges may need to be adjusted on multiple axes for each device depending on the scenario. As such we present an advanced WIMU in conjunction with a Smart WIMU system to simplify this aspect with 3 usage modes: Manual, Intelligent and Autonomous. Attendees will be able to compare the 3 different modes and see the effects of good andbad set-ups on the quality of data gathered in real time.
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The Republic of Ireland became the first European country to implement nationwide smoke-free workplace legislation. Aims: To determine prevalence of smoking among bar workers and estimate the impact of the smoke-free workplace legislation on their smoking behaviour to that of a comparable general population sample. To approximate the influence of tobacco control measures on risk perception of second-hand smoke (SHS) among the general population. To explore the de-normalisation of smoking behaviour and the potential increased stigmatisation of smokers and their smoking. Methods: Prevalence estimates and behavioural changes were examined among a random sample of bar workers before and 1 year after the smoke-free legislation; comparisons made with a general population sub-sample. Changes in risk knowledge related to SHS exposure were based on general population data. Qualitative interviews were conducted among a purposive sample of smokers and non-smokers four years after the implementation of the legislation. Results: Smoking prevalence was extremely high among bar workers. Smoking prevalence dropped in bar workers and significantly among the general population 1 year post ban while cigarette consumption dropped significantly among bar workers. Disparity in knowledge between smokers and non-smoker of risk associated with SHS exposure reduced. Lack of understanding of the risk of ear infections in children posed by SHS exposure was notable. Evidence for advanced de-normalisation of smoking behaviour and intensification of stigma because of the introduction of the legislation was dependent on many factors, quality of smoking facilities played a key role. Conclusions: Ireland’s smoke-free legislation was associated with a drop in prevalence and cigarette consumption. Disparity in knowledge between smokers and non-smokers of the risk posed by SHS exposure reduced however the risk of ear infections in children needs to be effectively disseminated. The proliferation of ‘good’ smoking areas may diminish the potential to reduce smoking behaviour and de-normalise smoking.
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We describe a general technique for determining upper bounds on maximal values (or lower bounds on minimal costs) in stochastic dynamic programs. In this approach, we relax the nonanticipativity constraints that require decisions to depend only on the information available at the time a decision is made and impose a "penalty" that punishes violations of nonanticipativity. In applications, the hope is that this relaxed version of the problem will be simpler to solve than the original dynamic program. The upper bounds provided by this dual approach complement lower bounds on values that may be found by simulating with heuristic policies. We describe the theory underlying this dual approach and establish weak duality, strong duality, and complementary slackness results that are analogous to the duality results of linear programming. We also study properties of good penalties. Finally, we demonstrate the use of this dual approach in an adaptive inventory control problem with an unknown and changing demand distribution and in valuing options with stochastic volatilities and interest rates. These are complex problems of significant practical interest that are quite difficult to solve to optimality. In these examples, our dual approach requires relatively little additional computation and leads to tight bounds on the optimal values. © 2010 INFORMS.
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The highest rates of fetal alcohol syndrome worldwide can be found in South Africa. Particularly in impoverished townships in the Western Cape, pregnant women live in environments where alcohol intake during pregnancy has become normalized and interpersonal violence (IPV) is reported at high rates. For the current study we sought to examine how pregnancy, for both men and women, is related to alcohol use behaviors and IPV. We surveyed 2,120 men and women attending drinking establishments in a township located in the Western Cape of South Africa. Among women 13.3% reported being pregnant, and among men 12.0% reported their partner pregnant. For pregnant women, 61% reported attending the bar that evening to drink alcohol and 26% reported both alcohol use and currently experiencing IPV. Daily or almost daily binge drinking was reported twice as often among pregnant women than non-pregnant women (8.4% vs. 4.2%). Men with pregnant partners reported the highest rates of hitting sex partners, forcing a partner to have sex, and being forced to have sex. High rates of alcohol frequency, consumption, binge drinking, consumption and binge drinking were reported across the entire sample. In general, experiencing and perpetrating IPV were associated with alcohol use among all participants except for men with pregnant partners. Alcohol use among pregnant women attending shebeens is alarmingly high. Moreover, alcohol use appears to be an important factor in understanding the relationship between IPV and pregnancy. Intensive, targeted, and effective interventions for both men and women are urgently needed to address high rates of drinking alcohol among pregnant women who attend drinking establishments.
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Low molecular weight opioid peptide esters (OPE) could become a class of analgesics with different side effect profiles than current opiates. OPE may have sufficient plasma stability to cross the blood brain barrier (BBB), undergo ester hydrolysis and produce analgesia. OPE of dipeptides, tyr-pro and tyr-gly conjugated to ethanol have a structure similar to the anesthestic agent, etomidate. Based upon the analgesic activity of dipeptide opioids, Lipinski's criteria, and permeability of select GABA esters to cross the BBB, opioid peptides (OP) conjugated to ethanol, cholesterol or 3-glucose are lead recommendations. Preliminary animal data suggests that tyr-pro-ethyl ester crosses the BBB and unexpectedly produces hyperalgesia. Currently, there are no approved OP analgesics available for clinical use. Clinical trials of good manufacturing practice OP administered to patients suffering from chronic pain with indwelling intrathecal pumps could resolve the issue that OP may be superior to opiates and may redirect research.
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During mitotic cell cycles, DNA experiences many types of endogenous and exogenous damaging agents that could potentially cause double strand breaks (DSB). In S. cerevisiae, DSBs are primarily repaired by mitotic recombination and as a result, could lead to loss-of-heterozygosity (LOH). Genetic recombination can happen in both meiosis and mitosis. While genome-wide distribution of meiotic recombination events has been intensively studied, mitotic recombination events have not been mapped unbiasedly throughout the genome until recently. Methods for selecting mitotic crossovers and mapping the positions of crossovers have recently been developed in our lab. Our current approach uses a diploid yeast strain that is heterozygous for about 55,000 SNPs, and employs SNP-Microarrays to map LOH events throughout the genome. These methods allow us to examine selected crossovers and unselected mitotic recombination events (crossover, noncrossover and BIR) at about 1 kb resolution across the genome. Using this method, we generated maps of spontaneous and UV-induced LOH events. In this study, we explore machine learning and variable selection techniques to build a predictive model for where the LOH events occur in the genome.
Randomly from the yeast genome, we simulated control tracts resembling the LOH tracts in terms of tract lengths and locations with respect to single-nucleotide-polymorphism positions. We then extracted roughly 1,100 features such as base compositions, histone modifications, presence of tandem repeats etc. and train classifiers to distinguish control tracts and LOH tracts. We found interesting features of good predictive values. We also found that with the current repertoire of features, the prediction is generally better for spontaneous LOH events than UV-induced LOH events.