40 research outputs found

    Quantum chemical calculations of X-ray emission spectroscopy

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    The calculation of X-ray emission spectroscopy with equation of motion coupled cluster theory (EOM-CCSD), time dependent density functional theory (TDDFT) and resolution of the identity single excitation configuration interaction with second order perturbation theory (RI-CIS(D)) is studied. These methods can be applied to calculate X-ray emission transitions by using a reference determinant with a core-hole, and they provide a convenient approach to compute the X-ray emission spectroscopy of large systems since all of the required states can be obtained within a single calculation removing the need to perform a separate calculation for each state. For all of the methods, basis sets with the inclusion of additional basis functions to describe core orbitals are necessary, particularly when studying transitions involving the 1s or- bitals of heavier nuclei. EOM-CCSD predicts accurate transition energies when compared with experiment, however, its application to larger systems is restricted by its computational cost and difficulty in converging the CCSD equations for a core-hole reference determinant, which become increasing problematic as the size of the system studied increases. While RI-CIS(D) gives accurate transition energies for small molecules containing first row nuclei, its application to larger systems is limited by the CIS states providing a poor zeroth order reference for perturbation theory which leads to very large errors in the computed transition energies for some states. TDDFT with standard exchange-correlation functionals predicts transition energies that are much larger than experiment. Optimization of a hybrid and short-range cor- rected functional to predict the X-ray emission transitions results in much closer agreement with EOM-CCSD. The most accurate exchange-correlation functional identified is a modified B3LYP hybrid functional with 66% Hartree-Fock exchange, denoted B66LYP, which predicts X-ray emission spectra for a range of molecules including fluorobenzene, nitrobenzene, ace- tone, dimethyl sulfoxide and CF3Cl in good agreement with experiment

    Elite Refereeing in Professional Soccer: A Case Study of Mental Skills Support

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    Refereeing a high-profile soccer game requires a unique blend of sports-specific knowledge, physical abilities, and mental skills. While mental skills instruction has been seen as an integral element of performance enhancement in elite sport, the application of sport psychology intervention for referees and match officials is far less prominent. This case study briefly describes the levels of stress associated with refereeing elite soccer matches and the impact of stress on officiating performance and subsequent self-confidence of soccer referees. The work then outlines the program of mental skills intervention that was delivered to an elite soccer referee working within the Scottish professional soccer leagues. The program of mental skills embraced five stages: (1) Education; (2) Assessment/ profiling; (3) Mental skill learning; (4) Application of mental skills in context; and (5) Evaluation, and this article centers on the way in which each of these stages was carried out. The case study describes how the mental skills instruction program was associated with improved refereeing performance, and provides some tentative advice for sport psychology practitioners who may wish to provide consultancy services within the domain of sports officiating

    A Review of Surgical Informed Consent: Past, Present, and Future. A Quest to Help Patients Make Better Decisions

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    Contains fulltext : 87422.pdf (publisher's version ) (Closed access)BACKGROUND: Informed consent (IC) is a process requiring a competent doctor, adequate transfer of information, and consent of the patient. It is not just a signature on a piece of paper. Current consent processes in surgery are probably outdated and may require major changes to adjust them to modern day legislation. A literature search may provide an opportunity for enhancing the quality of the surgical IC (SIC) process. METHODS: Relevant English literature obtained from PubMed, Picarta, PsycINFO, and Google between 1993 and 2009 was reviewed. RESULTS: The body of literature with respect to SIC is slim and of moderate quality. The SIC process is an underestimated part of surgery and neither surgeons nor patients sufficiently realize its importance. Surgeons are not specifically trained and lack the competence to guide patients through a legally correct SIC process. Computerized programs can support the SIC process significantly but are rarely used for this purpose. CONCLUSIONS: IC should be integrated into our surgical practice. Unfortunately, a big gap exists between the theoretical/legal best practice and the daily practice of IC. An optimally informed patient will have more realistic expectations regarding a surgical procedure and its associated risks. Well-informed patients will be more satisfied and file fewer legal claims. The use of interactive computer-based programs provides opportunities to improve the SIC process.1 juli 201

    Co-producing a Research Agenda for Sustainable Palm Oil

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    The rise of palm oil as the world’s most consumed vegetable oil has coincided with exponential growth in palm oil research activity. Bibliometric analysis of research outputs reveals a distinct imbalance in the type of research being undertaken, notably a disproportionate focus on biofuel and engineering topics. Recognizing the expansion of oil palm agriculture across the tropics and the increasing awareness of environmental, social, and economic impacts, we seek to reorientate the existing research agenda toward one that addresses the most fundamental and urgent questions defined by the palm oil stakeholder community. Following consultation with 659 stakeholders from 38 countries, including palm oil growers, government agencies, non-governmental organizations, and researchers, the highest priority research questions were identified within 13 themes. The resulting 279 questions, including 26 ranked as top priority, reveal a diversity of environmental and social research challenges facing the industry, ranging from the ecological and ecosystem impacts of production, to the livelihoods of plantation workers and smallholder communities. Analysis of the knowledge type produced from these questions underscores a clear need for fundamental science programmes, and studies that involve the consultation of non-academic stakeholders to develop “transformative” solutions to the oil palm sector. Stakeholders were most aligned in their choice of priority questions across the themes of policy and certification related themes, and differed the most in environmental feedback, technology and smallholder related themes. Our recommendations include improved regional academic leadership and coordination, greater engagement with private and public stakeholders in Africa, and Central and South America, and enhanced collaborative efforts with researchers in the major consuming countries of India and China.The online survey and focus groups were funded by the Geran Kursi Endowmen MPOB-UKM Malaysia, and the Royal Geographical Society UK. The residential workshop was supported from by British Council and Academy Science Malaysia via the UK Newton Ungku-Omar Fund. ZD, JB, and MS are supported by the UK Natural Environment Research Council (NE/K016407/1; http://lombok.nerc-hmtf.info/)

    Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

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    Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo
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