2,564 research outputs found

    A comparative study of benchmarking approaches for non-domestic buildings: Part 1 – Top-down approach

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    Benchmarking plays an important role in improving energy efficiency of non-domestic buildings. A review of energy benchmarks that underpin the UK’s Display Energy Certificate (DEC) scheme have prompted necessities to explore the benefits and limitations of using various methods to derive energy benchmarks. The existing methods were reviewed and grouped into top-down and bottom-up approaches based on the granularity of the data used. In the study, two top-down methods, descriptive statistics and artificial neural networks (ANN), were explored for the purpose of benchmarking energy performances of schools. The results were used to understand the benefits of using these benchmarks for assessing energy efficiency of buildings and the limitations that affect the robustness of the derived benchmarks. Compared to the bottom-up approach, top-down approaches were found to be beneficial in gaining insight into how peers perform. The relative rather than absolute feedback on energy efficiency meant that peer pressure was a motivator for improvement. On the other hand, there were limitations with regard to the extent to which the energy efficiency of a building could be accurately assessed using the top-down benchmarks. Moreover, difficulties in acquiring adequate data were identified as a key limitation to using the top-down approach for benchmarking non-domestic buildings. The study suggested that there are benefits in rolling out of DECs to private sector buildings and that there is a need to explore more complex methods to provide more accurate indication of energy efficiency in non-domestic buildings

    Quality of life and cognitive function in patients with pituitary insufficiency

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    This review is concerned with the psychosocial functioning and the quality of life in patients with pituitary insufficiency who are receiving conventional hormone replacement therapy. The possible negative effects of pituitary surgery, treatment with irradiation, and suboptimal replacement regimens with hormones other than growth hormone on mood, behaviour and cognitive functioning are discussed. The influence of growth hormone deficiency per se, and the outcome of growth hormone therapy in adult patients are addressed in detail. A possible mechanism for a direct effect of growth hormone on the brain is presented

    The influence of pre-experimental experience on social discrimination in rats (Rattus norvegicus)

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    The authors used laboratory rats (Rattus norvegicus) of known relatedness and contrasting familiarity to assess the potential effect of preexperimental social experience on subsequent social recognition. The authors used the habituation-discrimination technique, which assumes that multiple exposures to a social stimulus (e.g., soiled bedding) ensure a subject discriminates between the habituation stimulus and a novel stimulus when both are introduced simultaneously. The authors observed a strong discrimination if the subjects had different amounts of preexperimental experience with the donors of the 2 stimuli but a weak discrimination if the subjects had either equal amounts of preexperimental experience or no experience with the stimuli. Preexperimental social experience does, therefore, appear to influence decision making in subsequent social discriminations. Implications for recognition and memory research are discussed

    Study protocol: Delayed intervention randomised controlled trial within the Medical Research Council (MRC) Framework to assess the effectiveness of a new palliative care service

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    Background: Palliative care has been proposed to help meet the needs of patients who suffer progressive non-cancer conditions but there have been few evaluations of service development initiatives. We report here a novel protocol for the evaluation of a new palliative care service in this context. Methods/Design: Using the MRC Framework for the Evaluation of Complex Interventions we modelled a new palliative care and neurology service for patients severely affected by Multiple Sclerosis (MS). We conducted qualitative interviews with patients, families and staff, plus a literature review to model and pilot the service. Then we designed a delayed intervention randomised controlled trial to test its effectiveness as part of phase II of the MRC framework. Inclusion criteria for the trial were patients identified by referring clinicians as having unresolved symptoms or psychological concerns. Referrers were advised to use a score of greater than 8 on the Expanded Disability Scale was a benchmark. Consenting patients newly referred to the new service were randomised to either receive the palliative care service immediately (fast-track) or after a 12-week wait (standard best practice). Face to face interviews were conducted at baseline (before intervention), and at 4–6, 10–12 (before intervention for the standard-practice group), 16– 18 and 22–24 weeks with patients and their carers using standard questionnaires to assess symptoms, palliative care outcomes, function, service use and open comments. Ethics committee approval was granted separately for the qualitative phase and then for the trial. Discussion: We publish the protocol trial here, to allow methods to be reviewed in advance of publication of the results. The MRC Framework for the Evaluation of Complex Interventions was helpful in both the design of the service, methods for evaluation in convincing staff and the ethics committee to accept the trial. The research will provide valuable information on the effects of palliative care among non-cancer patients and a method to evaluate palliative care in this context

    A Cut Finite Element Method with Boundary Value Correction

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    In this contribution we develop a cut finite element method with boundary value correction of the type originally proposed by Bramble, Dupont, and Thomee. The cut finite element method is a fictitious domain method with Nitsche type enforcement of Dirichlet conditions together with stabilization of the elements at the boundary which is stable and enjoy optimal order approximation properties. A computational difficulty is, however, the geometric computations related to quadrature on the cut elements which must be accurate enough to achieve higher order approximation. With boundary value correction we may use only a piecewise linear approximation of the boundary, which is very convenient in a cut finite element method, and still obtain optimal order convergence. The boundary value correction is a modified Nitsche formulation involving a Taylor expansion in the normal direction compensating for the approximation of the boundary. Key to the analysis is a consistent stabilization term which enables us to prove stability of the method and a priori error estimates with explicit dependence on the meshsize and distance between the exact and approximate boundary

    A cut finite element method for a model of pressure in fractured media

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    We develop a robust cut finite element method for a model of diffusion in fractured media consisting of a bulk domain with embedded cracks. The crack has its own pressure field and can cut through the bulk mesh in a very general fashion. Starting from a common background bulk mesh, that covers the domain, finite element spaces are constructed for the interface and bulk subdomains leading to efficient computations of the coupling terms. The crack pressure field also uses the bulk mesh for its representation. The interface conditions are a generalized form of conditions of Robin type previously considered in the literature which allows the modeling of a range of flow regimes across the fracture. The method is robust in the following way: (1) Stability of the formulation in the full range of parameter choices; and (2) Not sensitive to the location of the interface in the background mesh. We derive an optimal order a priori error estimate and present illustrating numerical examples

    Predictors and rates of treatment-resistant tumor growth in acromegaly

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    Background: Multimodal therapy for acromegaly affords adequate disease control for many patients; however, there remains a subset of individuals that exhibit treatment-resistant disease. The issue of treatment-resistant pituitary tumor growth remains relatively under-explored. Methods: We assessed the literature for relevant data regarding the surgical, medical and radio-therapeutic treatment of acromegaly in order to identify the factors that were predictive of aggressive or treatment-resistant pituitary tumor behavior in acromegaly and undertook an assessment of the rates of failure to control tumor progression with available treatment modalities. Results: Young age at diagnosis, large tumor size, high growth hormone secretion and certain histological markers are predictors of future aggressive tumor behavior in acromegaly. Significant tumor regrowth occurs in less than 10% of cases thought to be cured surgically, whereas failure to control tumor growth is seen in less than 1% of patients receiving radiotherapy. Somatostatin analogs induce a variable degree of tumor shrinkage in acromegaly but up to 2.2% of somatostatin analog-treated tumors continue to grow. Relative to other therapies, limited data are available for pegvisomant, but these indicate that persistent tumor growth occurs in 1.6-2.9% of cases followed up regularly with serial magnetic resonance imaging scans. Conclusions: Treatment-resistant tumor progression occurs in a small minority of patients with acromegaly, regardless of treatment modality. Young patients with large tumors or those with high pre-treatment levels of growth hormone particularly warrant close monitoring for continued tumor progression during treatment for acromegaly
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