1,748 research outputs found
Practical considerations in the deployment of ground source heat pumps in older properties - a case study
A ground-sourced heat pump (GSHP) was installed in a former Vicarage in Cambridgeshire, with a mix of solid wall structure built in the late 1800s and cavity wall section built in the 2000s, previously heated by oil. This type of building is usually considered unsuitable for heat pumps, unless substantial insulation work and extensive replacement of radiators are undertaken. Although the building had undergone a degree of retrofit to increase insulation, the GSHP was installed with the existing radiators. A detailed thermal model for the house was built in ESP-r and validated against experimental measurements taken from sensors in every room. The expected heating demands were computed from the model based on weather data and the GSHP system was designed accordingly. A compromise was made between minimizing the size of the heat pump and the achievable energy savings, which could have important implications for the way incentives for low-emissions heating systems are set up. Using the initial SAP assessment would have led to a substantial oversizing of the heat pump. The data collected so far show that an SPF of 2.9 has been achieved whilst maintaining comfortable (18 °C) internal temperatures and emissions of CO2 have been reduced by 70%
Native rodent species are unlikely sources of infection for Leishmania (Viannia) braziliensis along the Transoceanic Highway in Madre de Dios, Peru.
An estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. In Peru's Amazon region, the department of Madre de Dios (MDD) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. Leishmania (Viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. However, essentially nothing is known regarding the reservoirs of this vector-borne, zoonotic parasite in MDD. Wild rodents have been suspected, or proven, to be reservoirs of several Leishmania spp. in various ecosystems and countries. Additionally, people who live or work in forested terrain, especially those who are not regionally local and whose immune systems are thus naïve to the parasite, are at most risk for contracting L. (V.) braziliensis. Hence, the objective of this study was to collect tissues from wild rodents captured at several study sites along the Amazonian segment of the newly constructed Transoceanic Highway and to use molecular laboratory techniques to analyze samples for the presence of Leishmania parasites. Liver tissues were tested via polymerase chain reaction from a total of 217 rodents; bone marrow and skin biopsies (ear and tail) were also tested from a subset of these same animals. The most numerous rodent species captured and tested were Oligoryzomys microtis (40.7%), Hylaeamys perenensis (15.7%), and Proechimys spp. (12%). All samples were negative for Leishmania, implying that although incidental infections may occur, these abundant rodent species are unlikely to serve as primary reservoirs of L. (V.) braziliensis along the Transoceanic Highway in MDD. Therefore, although these rodent species may persist and even thrive in moderately altered landscapes, we did not find any evidence to suggest they pose a risk for L. (V.) braziliensis transmission to human inhabitants in this highly prevalent region
Influence of presence and patterns of late gadolinium enhancement on left ventricular remodeling after heart transplantation
Effectiveness of the flipped classroom methodology In the performance of higher education students: systematic review with meta-analysis
Introduction: The methodology Flipped Classroom (FC) consists in individual activities that the student has to do at home through the use of technologies which help the student to prepare for class, and during classes, activities are performed as more dynamic classes centered on the student. Through the years, the success has reached the maximum levels of performance and satisfaction in the teaching sessions in different areas of education compared to the classical methods, and there are no conclusive and considerable studies that compile and analyze this information succinctly. Objective: To analyze experimental and quasi-experimental studies that evaluate the methodology database in FC in performance and student satisfaction in comparison with the expository methodology. Methodology: This article is a systematic review that analyzes the randomized controlled trial (RCT) and Quasi-experimental studies selected with the methodology FC, which measures the efficacy through the results achieved in the realization and evaluation of the students. These articles were found in EBSCOhost and PubMed. Results: We selected 41 articles, that fulfilled all inclusion criteria established by the authors, for the accomplishment of this systematic review. Discussion: The results of our meta-analysis, both RCTs and quasi-experimental studies, point to a better effectiveness of the FC methodology compared to the expository methodology in academic performance. However, there is a heterogeneity in planned and developed activities during class, which means that our conclusions can’t be generalized. The poor methodological quality of the included studies, especially quasi-experimental studies, does not allow our conclusions about efficacy to be vigorous. Nevertheless, based on these first promising data, it seems to us that this methodology offers learning opportunities that aren’t possible in a classroom based on lectures and subject matter exposition. Conclusion: Although the articles selected have poor methodological quality, and it is necessary more rigorous investigations on this methodology, we believe that the FC methodology could revolutionize teaching methods and replace traditional teaching, which is so deeply rooted in today's society and doesn’t seems to favor the achievement of transversal competences.info:eu-repo/semantics/publishedVersio
Optimization of the effect of pineapple by-products enhanced in bromelain by hydrostatic pressure on the texture and overall quality of silverside beef cut
Dehydrated pineapple by-products enriched in bromelain using a hydrostatic pressure treatment (225 MPa, 8.5 min) were added in marinades to improve beef properties. The steaks from the silverside cut (2 ± 0.5 cm thickness and weight 270 ± 50 g), characterized as harder and cheaper, were immersed in marinades that were added to dehydrated and pressurized pineapple by-products that corresponded to a bromelain concentration of 0–20 mg tyrosine, 100 g−1 meat, and 0–24 h time, according to the central composite factorial design matrix. Samples were characterized in terms of marination yield, pH, color, and histology. Subsequently, samples were cooked in a water-bath (80 °C, 15 min), stabilized (4 °C, 24 h), and measured for cooking loss, pH, color, hardness, and histology. Marinades (12–24 h) and bromelain concentration (10–20 mg tyrosine.100 g−1 meat) reduced pH and hardness, increased marination yield, and resulted in a lighter color. Although refrigeration was not an optimal temperature for bromelain activity, meat hardness decreased (41%). Thus, the use of pineapple by-products in brine allowed for the valorization of lower commercial value steak cuts.The first author acknowledges the financial support from Fundação para a Ciência e a Tecnologia (FCT),Portugal, through a doctoral fellowship (SFRH/BD/109124/2015). This work was supported by the national fundingof FCT, under the scope of the strategic funding to the research units LEAF, Linking Landscape, Environment,Agriculture and Food, School of Agriculture, University of Lisbon, 1349-017 Lisbon (UIDP/04129/2020), CIISA,Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon,1300-477, Lisbon (UIDB/00276/2020) FMV and PDR2020-1.0.1-FEADER-031359, funded by the European RegionalDevelopment Fund (ERDF)), QOPNA (UID/QUI/00062/2019), LAQV-REQUIMTE, Department of Chemistry,University of Aveiro, 3810-193 Aveiro (UIDB/50006/2020) and CEB, Centre of Biological Engineering, Departmentof Biological Engineering, University of Minho, 4710–057 Braga (UIDP/04469/2019) through national funds andwhere applicable co-financed by the FEDER, within the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersio
The effect of handlebar height and bicycle frame length on muscular activity during cycling: a pilot study
The cycling literature is filled with reports of electromyography (EMG) analyses for a better understanding of muscle function during cycling. This research is not just limited to performance, as the cyclist’s goal may be rehabilitation, recreation, or competition, so a bicycle that meets the rider’s needs is essential for a more efficient muscular activity. Therefore, the purpose of this study was to understand the contribution of the activity of each of the following muscles: TD (trapezius descending), LD (latissimus dorsi), GM (gluteus maximus), and AD (anterior deltoid) in response to different bicycle-rider systems (handlebar height; bicycle frame length) and intensities in a bicycle equipped with a potentiometer. Surface EMG signals from muscles on the right side of the body were measured. A general linear model test was used to analyze the differences between muscle activation in the test conditions. Effect sizes were calculated using a partial Eta2 (η 2 ). The level of significance was set at 0.05. Muscle activation of different muscles differs, depending on the cycling condition (Pillai’s trace = 2.487; F (36.69) = 9.300; p < 0.001. η 2 = 0.958), mostly during low intensities. In high intensities, one specific pattern emerges, with a greater contribution of GM and TD and weaker participation of LD and AD, enhancing the cycling power output.info:eu-repo/semantics/publishedVersio
Promoting health-related cardiorespiratory fitness in physical education : the role of class intensity and habitual physical activity
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Physical education (PE) has the potential to promote health-related fitness, however, its contribution is still not clear. The aim of this study was to assess whether students' health-related cardiorespiratory fitness (CRF) improved from the beginning to the end of the school year, and to examine the role of PE class intensity and habitual physical activity (PA) in promoting students' CRF. This observational study employed a longitudinal design. Participants were 212 7th and 8th grade students (105 boys), mean age 12.9 years old, followed during one school year, from September 2017 to June 2018. The Progressive Aerobic Cardiovascular Endurance Run (PACER) was used to assess CRF at baseline and follow-up. PA was measured using accelerometers. PE class intensity was assessed using the System for Observing Fitness Instruction Time. Findings indicated that from the beginning to the end of the school year, a greater percentage of participants were in the CRF healthy fitness zone (73.1% to 79.7%, p = 0.022). Among boys, participating in organized sports (B = 4.61, 95% confidence interval [CI]: 0.33, 8.88) and the percentage of PE time being very active (B = 0.90, 95% CI: 0.44, 1.35) were positively associated with the change in PACER laps. Among girls, daily vigorous PA (B = 0.38, 95% CI: 0.15, 0.60) and participating in organized sports (B = 4.10, 95% CI: 0.93, 7.27) were also positively associated with PACER change, while being overweight or obese (B = -5.11, 95% CI: -8.28, -1.93) was negatively associated. In conclusion, PE was demonstrated to have a positive role in the promotion of CRF, especially among boys, while for girls, habitual PA seems to have a greater contribution. Nevertheless, results and conclusions should be considered carefully, taking into account study limitations, such as the non-direct measures of PE class intensity, CRF, and school setting.M.P. is supported by Fundação para a Ciência e a Tecnologia (FCT), grant number SFRH/BD/122219/2016. CIPER is financed by Fundação para a Ciência e a Tecnologia (FCT) within the unit I&D 472, grant number UID/DTP/00447/2019.info:eu-repo/semantics/publishedVersio
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