3,914 research outputs found

    Influencing factors in energy use of housing blocks: a new methodology, based on clustering and energy simulations, for decision making in energy refurbishment projects

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    In recent years, big efforts have been dedicated to identify which are the factors with highest influence in the energy consumption of residential buildings. These factors include aspects such as weather dependence, user behaviour, socio-economic situation, type of the energy installations and typology of buildings. The high number of factors increases the complexity of analysis and leads to a lack of confidence in the results of the energy simulation analysis. This fact grows when we move one step up and perform global analysis of blocks of buildings. The aim of this study is to report a new methodology for the assessment of the energy performance of large groups of buildings when considering the real use of energy. We combine two clustering methods, Generative Topographic Mapping and k-means, to obtain reference dwellings that can be considered as representative of the different energy patterns and energy systems of the neighbourhood. Then, simulation of energy demand and indoor temperature against the monitored comfort conditions in a short period is performed to obtain end use load disaggregation. This methodology was applied in a district at Terrassa City (Spain), and six reference dwellings were selected. Results showed that the method was able to identify the main patterns and provide occupants with feasible recommendations so that they can make required decisions at neighbourhood level. Moreover, given that the proposed method is based on the comparison with similar buildings, it could motivate building occupants to implement community improvement actions, as well as to modify their behaviour

    Patient-Reported Outcomes Measurement Information System physical function correlates with Toronto Extremity Salvage Score in an orthopaedic oncology population

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    Background: The National Institute of Health\u27s Patient-Reported Outcomes Measurement Information System (PROMIS) uses computerised-adaptive testing to reduce survey burden and improve sensitivity. PROMIS is being used across medical and surgical disciplines but has not been studied in orthopaedic oncology. Questions/purposes: The aim of the study was to compare PROMIS measures with upper extremity (UE) and lower extremity (LE) Toronto Extremity Salvage Score (TESS) by assessing the following: (1) responder burden, (2) correlation between scores and (3) floor/ceiling effects. Patients and methods: This cross-sectional trial analysed all 97 adult patients treated surgically for a bone or soft tissue tumour at a tertiary institution between November 2015 and March 2016. TESS (UE or LE) and PROMIS (Physical Function, Pain Interference and Depression) surveys were administered preoperatively. Pearson correlations between each PROMIS domain and TESS were calculated, as were floor/ceiling effects of each outcome measure. Results: (1) Completion of three PROMIS questionnaires required a mean total of 16.8 (+/- 5.8 standard deviation) questions, compared with 31 and 32 questions for the LE and UE TESS questionnaires, respectively. (2) The PROMIS Physical Function scores demonstrated a strong positive correlation with the LE TESS (r = 0.84; 95% confidence interval [CI], 0.72-0.91; p \u3c 0.001) and moderate positive correlation with the UE TESS (r = 0.64; 95% CI, 0.34-0.83; p = 0.055). The PROMIS Depression scores demonstrated a weak negative correlation with both the LE TESS (r = -0.38; 95% CI, -0.61 to -0.10; p = 0.010) and with UE TESS (r = -0.38; 95% CI, -0.67 to -0.01; p = 0.055). The PROMIS Pain Interference scores demonstrated a strong negative correlation with the LE TESS (r = -0.71; 95% CI, -0.83 to -0.52; p \u3c 0.001) and a moderate negative correlation with the UE TESS (r = -0.62; 95% CI, -0.81 to -0.30; p = 0.001). (3) The UE TESS had a range of scores from 16 to 100 with a 27% ceiling effect and no floor effect, and the LE TESS had a range from 10 to 98 with no floor or ceiling effect. There was no floor or ceiling effect for any PROMIS measures. Conclusions: In an orthopaedic oncology population, the PROMIS Physical Function and Pain Interference scores correlate with the TESS and have the benefit of reduced survey burden and ceiling effect. The PROMIS Depression scores may provide additional information regarding patient outcomes not captured by the TESS. Level of Evidence: Level III. The translational potential of this article: Patient reported outcome measures asses patients\u27 symptoms, function and health-related quality of life and are designed to capture more clinical information than can be gathered by objective medial testing alone. As reimbursements and the understanding of patient outcomes are becoming tied to performance on PROMIS measures, it is an important step to establish how PROMIS measures correlate and compare to traditional legacy measures

    Guía para visitar la Catedral de León

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    Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

    Carbon and oxygen in HII regions of the Magellanic Clouds: abundance discrepancy and chemical evolution

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    We present C and O abundances in the Magellanic Clouds derived from deep spectra of HII regions. The data have been taken with the Ultraviolet-Visual Echelle Spectrograph at the 8.2-m VLT. The sample comprises 5 HII regions in the Large Magellanic Cloud (LMC) and 4 in the Small Magellanic Cloud (SMC). We measure pure recombination lines (RLs) of CII and OII in all the objects, permitting to derive the abundance discrepancy factors (ADFs) for O^2+, as well as their O/H, C/H and C/O ratios. We compare the ADFs with those of other HII regions in different galaxies. The results suggest a possible metallicity dependence of the ADF for the low-metallicity objects, but more uncertain for high-metallicity objects. We compare nebular and B-type stellar abundances and we find that the stellar abundances agree better with the nebular ones derived from collisionally excited lines (CELs). Comparing these results with other galaxies we observe that stellar abundances seem to agree better with the nebular ones derived from CELs in low-metallicity environments and from RLs in high-metallicity environments. The C/H, O/H and C/O ratios show almost flat radial gradients, in contrast with the spiral galaxies where such gradients are negative. We explore the chemical evolution analysing C/O vs. O/H and comparing with the results of HII regions in other galaxies. The LMC seems to show a similar chemical evolution to the external zones of small spiral galaxies and the SMC behaves as a typical star-forming dwarf galaxy.Comment: Accepted for publication in MNRAS, 17 pages, 11 figures, 8 table

    Effects of a 16-week training program with a pyramidal intensity distribution on recreational male cyclists

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    Different training intensity distributions (TIDs) have been proposed to improve cycling performance, especially for high-competition athletes. The objectives of this study were to analyze the effect of a 16-week pyramidal training intensity distribution on somatic and power variables in recreational cyclists and to explore the training zone with the greatest impact on performance improvement. The sample consisted of 14 male recreational cyclists aged 41.00 ± 7.29 years of age. A number of somatic variables were measured. During an incremental protocol, power at a 4 mMol·L−1 blood lactate concentration (P4), corresponding power to body mass ratio (P/W P4), and heart rate (HR P4) were also measured. Among the somatic variables, the percentage of fat mass showed the greatest improvement between moments (p < 0.001, d = 0.52). Both P4 (p < 0.001, d = 1.21) and P/W P4 (p < 0.001, d = 1.54) presented a significant increase between moments. The relative improvement in P4 (% P4) showed a significant correlation (Rs = 0.661, p = 0.038) and relationship (R2 = 0.61, p = 0.008) mainly with training zone Z2 (blood lactate levels ≥ 2 and <4 mMol·L−1). It seems that spending more time in Z2 promoted an improvement in both somatic and power variables in recreational cyclists.This research was funded by FCT—Portuguese Foundation for Science and Technology, grant number UIDB/DTP/04045/2020.info:eu-repo/semantics/publishedVersio

    Cost-effectiveness of cerebrospinal biomarkers for the diagnosis of Alzheimer’s disease

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    Background: Accurate and timely diagnosis of Alzheimer’s disease (AD) is important for prompt initiation of treatment in patients with AD and to avoid inappropriate treatment of patients with false-positive diagnoses. Methods: Using a Markov model, we estimated the lifetime costs and quality-adjusted life-years (QALYs) of cerebrospinal fluid biomarker analysis in a cohort of patients referred to a neurologist or memory clinic with suspected AD who remained without a definitive diagnosis of AD or another condition after neuroimaging. Parametric values were estimated from previous health economic models and the medical literature. Extensive deterministic and probabilistic sensitivity analyses were performed to evaluate the robustness of the results. Results: At a 12.7% pretest probability of AD, biomarker analysis after normal neuroimaging findings has an incremental cost-effectiveness ratio (ICER) of 11,032perQALYgained.ResultsweresensitivetothepretestprevalenceofAD,andtheICERincreasedtoover11,032 per QALY gained. Results were sensitive to the pretest prevalence of AD, and the ICER increased to over 50,000 per QALY when the prevalence of AD fell below 9%. Results were also sensitive to patient age (biomarkers are less cost-effective in older cohorts), treatment uptake and adherence, biomarker test characteristics, and the degree to which patients with suspected AD who do not have AD benefit from AD treatment when they are falsely diagnosed. Conclusions: The cost-effectiveness of biomarker analysis depends critically on the prevalence of AD in the tested population. In general practice, where the prevalence of AD after clinical assessment and normal neuroimaging findings may be low, biomarker analysis is unlikely to be cost-effective at a willingness-to-pay threshold of $50,000 per QALY gained. However, when at least 1 in 11 patients has AD after normal neuroimaging findings, biomarker analysis is likely cost-effective. Specifically, for patients referred to memory clinics with memory impairment who do not present neuroimaging evidence of medial temporal lobe atrophy, pretest prevalence of AD may exceed 15%. Biomarker analysis is a potentially cost-saving diagnostic method and should be considered for adoption in high-prevalence centers

    A cooling system for a hybrid PV/thermal linear concentrator

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    This paper presents the thermal evaluation of an evacuated PVT collector designed to operate under concentrated radiation (15 suns). Finite volume 3D numerical computations have been carried out in order to study the thermal characteristics of different rectangular cross section aluminium pipes and to test the performance of the PVT collector with several laminar flow rates. Experiments with the same laminar flows show the same behavior than in the numerical results
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