bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy Efficiency in K-12 Schools: A Case Study in Florida
Authors: Doiphode Ganesh , Najafi Hamidreza , Favaretto Mariana Migliori 
Published: September 2020

Abstract
Buildings are one of the largest energy consumers in the United States. K-12 schools are responsible for nearly 8% of energy consumption by commercial buildings which is equivalent to 1.44% of total annual energy consumption in the country. Understanding the baseline energy consumption of the schools as well as identifying effective energy efficiency measures (EEMs) that result in significant energy savings without compromising occupant’s comfort in a given climate condition are essential factors in moving towards a sustainable future. In a collaboration between Florida Institute of Technology and Brevard Public Schools, three schools are identified for a test study in Melbourne, FL, representing the humid subtropical climate. Energy audit is conducted for these schools and monthly utility bill data as well as background information, end-user’s data and their associated operating schedules are obtained. A detailed analysis is performed on the utility bill data and energy consumption by each end-user is estimated. Several EEMs are considered and evaluated to achieve an improved energy efficiency for the schools. The implementation cost of each EEM and the associated simple payback period is also determined. A study is also conducted to explore possibility of using solar power to cover 50% of energy requirements of each school and the cost and payback period of the project are evaluated. The results of this paper provide insights regarding prioritizing energy efficiency projects in K-12 schools in humid subtropical climates and particularly the state of Florida and help with decision making regarding investment in on-site power generation using solar energy.
Investigation of Temperature Limitations During Rapid Thermal Cycling of a Micro-Tubular Flame-Assisted Fuel Cell
Authors: Milcarek Ryan J. , Ghotkar Rhushikesh , Ahn Jeongmin 
Published: September 2020

Abstract
Despite many efforts and improvements over the last few decades, two of the major challenges facing Solid Oxide Fuel Cells (SOFCs) are slow heating rates to operating conditions (typically &lt; 5 °C.min−1) and a limited ability to thermal cycle (&lt; 200 cycles). Recently a novel hybridized setup that combines a fuel-rich combustion reformer with a SOFC was developed and utilized to investigate rapid heating, cooling and thermal cycling of a micro-Tubular SOFC. The setup places the SOFC directly in the flame and exhaust of the high temperature combustion of methane, which allows for extremely rapid temperature rise in the SOFC. A SOFC with a (La0.8Sr0.2)0.95MnO3-x cathode was tested in the setup, but limitations on air preheating for the cathode resulted in low SOFC cathode temperatures (∼500°C) and low power density. Thermal insulation improved pre-heating of the air delivered to the cathode, increased the SOFC cathode temperature and, when a (La0.60Sr0.40)0.95Co0.20Fe0.80O3-x cathode was applied to the SOFC, resulted in improved power density. After adjusting the thermal insulation, the air temperature near the cathode exceeded ∼750°C during testing. Over 3,000 thermal cycles were conducted at a heating rate exceeding 900°C.min−1 and a cooling rate that exceeded 300°C.min−1. The open circuit voltage was analyzed over the 150 h test and a low degradation rate of ∼0.0008V per 100 cycles per fuel cell was observed. Unlike the previous test, which was conducted at lower temperatures, significant degradation of the current collector was observed during this test. Electrochemical impedance spectroscopy shows that degradation in the SOFC was due to increases in ohmic losses, activation losses at the cathode and increased concentration losses. The setup demonstrates that rapid thermal cycling of micro-Tubular SOFCs can be achieved, but there are limitations on the maximum temperature that can be sustained depending on the current collector.
Revisiting Theoretical Limits for One-Degree-of-Freedom Wave Energy Converters
Authors: Tom Nathan M. 
Published: September 2020

Abstract
This work revisits the theoretical limits of one-degree-of-freedom wave energy converters. This paper considers the floating sphere used in the Ocean Energy Systems Task 10 Wave Energy Converter modeling and verification effort for analysis. Analytical equations are derived to determine bounds on the motion amplitude, time-averaged power, and power-take-off (PTO) force. A unique result was found that shows the time-averaged power absorbed by a wave energy converter can be defined solely by the inertial properties and radiation hydrodynamic coefficients. In addition, a unique expression for the PTO force amplitude was derived that has provided upper and lower bounds when resistive control is used to maximize power generation. For complex conjugate control, this same expression can only provide a lower bound, as there is theoretically no upper bound. These bounds are used to compare the performance of a floating sphere if it were to extract energy using surge or heave motion. The analysis shows that because of the differences in hydrodynamic coefficients of each oscillating mode, there will be different frequency ranges that provide better power capture efficiency. The influence of a motion constraint on power absorption while also utilizing a nonideal power take-off is examined and found to reduce the losses associated with bidirectional energy flow. The expression to calculate the time-averaged power with a nonideal PTO is modified by the mechanical-to-electrical efficiency and the ratio of the PTO spring and damping coefficients. The PTO spring and damping coefficients were separated in the expression, which allows for limits to be set on the possible values of PTO coefficients to ensure a net flow of power to the grid.
Design of Fresnel Lens With Constant Height Spherical Facets
Authors: Awasthi Kuldeep , Shashidhar Reddy Desireddy , Khan Mohd. Kaleem 
Published: September 2020

Abstract
In the present work, a ray tracing model based on Snell’s law of refraction is developed using MATLAB for the design of Fresnel lens with spherical facets of equal height. In practice, the facet curvature is approximated by straight line, which causes an increase in spherical aberrations and reduction in concentration ratio. The proposed model takes facet curvature into consideration, which will result in effective utilization of incident solar radiations. Fresnel lenses are available with facets having constant width and facets with constant height. A comparison of spherical aberrations in the two cases has also been presented using different f - numbers (ratio of focal length to aperture diameter). Effect of different parameters like number of facets and refractive index of lens material on concentration ratio is also presented in present study. The proposed ray tracing model is validated with the model developed in SolTrace, an open access software. The predictions from the proposed model are in good agreement with the results of SolTrace model with an average deviations of 6.8% for concentration ratio and 2.2% for focal length.
Improving Next-Generation Falling Particle Receiver Designs Subject to Anticipated Operating Conditions
Authors: Mills Brantley , Shaeffer Reid , Yue Lindsey , Ho Clifford K. 
Published: September 2020

Abstract
The thermal performance of a candidate next-generation falling particle receiver (FPR) is analyzed subject to various expected operating conditions. This receiver design was created from the result of an extensive optimization study and developed to support the Generation 3 Particle Pilot Plant (G3P3) project. Previous analysis demonstrated high thermal efficiencies for the receiver at nominal quiescent conditions, but further analysis was required to demonstrate that the receiver could maintain that thermal performance in a wide range of anticipated environments. In this study, the thermal efficiency was numerically evaluated using a CFD model for different wind conditions and shown to maintain a thermal efficiency above 83% for considered wind conditions. Moreover, the effect of radiative spillage from the incoming concentrated solar beam on the receiver exterior was investigated using ray tracing and CFD models. The exterior wall material temperature limits were not exceeded for the anticipated design power from the heliostats. Additional features were numerically explored including the addition of a chimney to capture particle fines and waste heat and a multi-stage concept to maximize curtain opacity. Particle fines of 10 μm were shown to preferentially flow into this chimney rather than out of the aperture, and the multi-stage design decreased radiative losses and minimized wall temperatures behind the particle curtain.
First-cycle sand supply and the evolution of the eastern Canadian continental margin: Insights from Pb isotopes in the Mesozoic Scotian Basin
Authors: Blowick Aoife , Pe-Piper Georgia , Piper David J.W. , Zhang Yuanyuan , Tyrrell Shane 
Published: September 2020

AbstractProvenance analysis provides a powerful means to understand, connect, and reconstruct source-to-sink systems and Earth surface processes, if reliable toolkits can be developed, refined, and applied. Deciphering sediment routing to the Scotian Basin, offshore eastern Canada, is marred by sedimentary recycling but is critical to understanding the evolution of the Canadian margin in response to the evolving Labrador rift. In this study, Pb isotopes in detrital K-feldspars were fingerprinted in 13 wells across the Scotian Basin to track first-cycle sand supply. Unlike previous approaches, which utilized less labile proxies such as zircon, detrital K-feldspars are unlikely to survive multiple sedimentary cycles.The Pb-isotopic data reveal a dynamic seesaw effect between hinterland sources across the Jurassic-Cretaceous boundary, reflecting the complex interplay between the northward propagation of uplift along the rising Labrador rift flank and the reactivation of fault systems in the lower drainage basin. Pb isotopes in K-feldspar record progressively increasing long-distance supply from eastern Labrador, as early as the Callovian in the central basin, alongside diminishing but persistent local sourcing from adjacent Appalachian terranes. Comparison with more resilient mineral proxies, notably zircon, appears to confirm recycling in the lower drainage basin and highlights the limitations of using a single mineral proxy in isolation.This case study serves as an example of the growing potential of multiproxy provenance toolkits not only to decipher sediment-routing corridors in paleodrainage systems, but to better define and connect the drivers, mechanisms, and spatial and temporal ranges of Earth surface processes and tectonic events.
Influence of corneal guttae and nuclear cataract on contrast sensitivity
Authors: Augustin Victor A , Weller Julia M , Kruse Friedrich E , Tourtas Theofilos 
Published: September 2020

AIMSTo evaluate the contrast sensitivity in patients with nuclear cataract and corneal guttae compared to patients with nuclear cataract without guttae.METHODSIn this retrospective, single-centre case series, 50 eyes of 50 patients fulfilling the inclusion criteria were enrolled. Patients with corneal guttae and nuclear cataract (n=25, study group) underwent triple Descemet membrane endothelial keratoplasty (DMEK). Patients with nuclear cataract and healthy corneas underwent cataract surgery (n=25, control group). Inclusion criteria were preoperative best-corrected visual acuity ≥20/40, no corneal oedema and similar lens opacity (nuclear opalescence 2.0–2.9). Outcome measures included MARS letter and OPTEC 6500P contrast sensitivity test, corneal volume, central corneal thickness and anterior and posterior corneal densitometry.RESULTSPreoperative MARS letter and OPTEC 6500P contrast sensitivity was significantly worse in the study group (MARS: p<0.001; OPTEC 6500P: p<0.007 at low spatial frequencies in daylight with and without glare and nightlight without glare). After surgery, there was no significant difference in MARS letter contrast sensitivity between groups (p=0.225). OPTEC 6500P contrast sensitivity remained significantly lower in the study group in daylight and nightlight with and without glare at most spatial frequencies (p<0.01) postoperatively. Preoperative and postoperative corneal volume, central corneal thickness and anterior corneal densitometry were equal in both groups (p>0.05). Posterior densitometry was significantly higher in the study group than in the control group preoperatively (p<0.001) but turned into equal values postoperatively (p=0.07).CONCLUSIONSCorneal guttae cause an additional significant decrease in contrast sensitivity in eyes with nuclear cataract. This is in favour of performing a triple DMEK even in eyes with a visual acuity of ≥20/40.
Effectiveness of a high volume injection as treatment for chronic Achilles tendinopathy: randomised controlled trial
Authors: van der Vlist Arco C , van Oosterom Robert F , van Veldhoven Peter L J , Bierma-Zeinstra Sita M A , Waarsing Jan H , Verhaar Jan A N , de Vos Robert-Jan 
Published: September 2020

AbstractObjectiveTo study whether a high volume injection without corticosteroids improves clinical outcome in addition to usual care for adults with chronic midportion Achilles tendinopathy.DesignPatient and assessor blinded, placebo controlled randomised clinical trial.SettingSports medicine department of a large district general hospital, the Netherlands.Participants80 adults (aged 18-70 years) with clinically diagnosed chronic midportion Achilles tendinopathy and neovascularisation on ultrasonography. 39 were randomised to a high volume injection without corticosteroids and 41 to placebo.InterventionsParticipants were instructed to perform an exercise programme for 24 weeks (usual care) combined with one 50 mL high volume injection of saline and lidocaine (intervention group) or one 2 mL placebo injection of saline and lidocaine (placebo group) at baseline.Main outcome measuresPrimary outcome was pain and function assessed using the validated Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire at 24 weeks (analysed using a generalised estimation equations model). Secondary outcomes were patient satisfaction, return to sport, degree of ultrasonographic Doppler flow, visual analogue scale on 10 hop test, power and flexibility of the gastrocnemius and soleus muscles, pain detect questionnaire for neuropathic pain, and pain coping inventory. Participants were evaluated at baseline and at 2, 6, 12, and 24 weeks.ResultsOnly one participant (1%) was lost to follow-up. The estimated mean VISA-A score improved significantly, from 40.4 (95% confidence interval 32.0 to 48.7) at baseline to 59.1 (50.4 to 67.8) at 24 weeks in the high volume injection group and from 36.9 (27.1 to 46.8) to 58.5 (47.9 to 69.1) in the placebo group. The VISA-A score over time did not differ between the groups (adjusted between group difference at 24 weeks 0.5 points, 95% confidence interval −17.8 to 18.8). No significant between group differences were found for patient satisfaction (21/37 (57%)v19/39 (49%) patients, P=0.50) and return to desired sport (15/29 (52%)v19/31 (61%) patients active in sports, P=0.65) at 24 weeks. None of the other secondary outcomes differed between the two groups.ConclusionsA high volume injection without corticosteroids in addition to usual care is not effective for symptom reduction in patients with chronic midportion Achilles tendinopathy. On the basis of our findings, we cannot recommend the use of a high volume injection in this patient group.Trial registrationClinicalTrials.govNCT02996409
Sex-specific trends in smoking prevalence over seven years in different Austrian populations: results of a time-series cross-sectional analysis
Authors: Dorner Thomas Ernst , Brath Helmut , Kautzky-Willer Alexandra 
Published: September 2020

ObjectivesAim of this study was to examine trends over time in smoking status in men and women, and in subgroups, in Austria, a country with poor smoking regulation policies.Design and participantsTwo cross-sectional surveys (Austrian Health Interview Surveys for 2007 and 2014), each with more than 15 000 participants from the general population, aged ≥15 years.Outcome measuresPrevalence of self-reported daily smoking. ORs for daily smoking in subgroups, presented as results of logistic regression models, adjusted for sociodemographic variables and presence of chronic diseases.ResultsPrevalence of daily cigarette smoking was 26.0% for men in both years, and increased from 19.1% to 22.0% (p<0.001) in women from 2007 to 2014. Smoking prevalence increased especially in female patients with diabetes mellitus (from 9.9% to 16.4%, p=0.005), obesity (from 17.1% to 21.6%, p=0.010) and hypertension (from 11.2% to 14.2%, p=0.010). Smoking prevalence increased significantly in unemployed men (from 43.6% to 57.1%, p<0.001). In women, smoking prevalence increased in those aged 30–64 years (from 21.9% to 26.3%, p<0.001) and 65+ (from 3.9% to 6.2%, p=0.002), with primary (from 17.2% to 24.4%, p<0.001) and secondary education (from 21.4% to 23.4%, p=0.021), and with a European (from 16.6% to 26.1%, p<0.001) and non-European migration background (from 25.0% to 32.8%, p=0.003). In the adjusted analysis for women in 2014, there was a higher likelihood of smoking (OR 1.22, 95% CI 1.12 to 1.32, p<0.001) compared with 2007, and for those affected by a chronic disease (OR 1.15, 95% CI 1.06 to 1.25, p=0.002).ConclusionsThere has been a remarkable increase in smoking prevalence over the 7-year period in women in Austria, especially for those with chronic diseases, higher age, lower education and a migration background. Better political and clinical efforts are needed to reduce the high tobacco use in Austria.
Impact of a national primary care pay-for-performance scheme on ambulatory care sensitive hospital admissions: a small-area analysis in England
Authors: Grigoroglou Christos , Munford Luke , Webb Roger , Kapur Navneet , Doran Tim , Ashcroft Darren , Kontopantelis Evangelos 
Published: September 2020

ObjectiveWe aimed to spatially describe hospital admissions for ambulatory care sensitive conditions (ACSC) in England at small-area geographical level and assess whether recorded practice performance under one of the world’s largest primary care pay-for-performance schemes led to reductions in these potentially avoidable hospitalisations for chronic conditions incentivised in the scheme.SettingWe obtained numbers of ACSC hospital admissions from the Hospital Episode Statistics database and information on recorded practice performance from the Quality and Outcomes Framework (QOF) administrative dataset for 2015/2016. We fitted three sets of negative binomial models to examine ecological associations between incentivised ACSC admissions, general practice performance, deprivation, urbanity and other sociodemographic characteristics.ResultsHospital admissions for QOF incentivised ACSCs varied within and between regions, with clusters of high numbers of hospital admissions for incentivised ACSCs identified across England. Our models indicated a very small effect of the QOF on reducing admissions for incentivised ACSCs (0.993, 95% CI 0.990 to 0.995), however, other factors, such as deprivation (1.021, 95% CI 1.020 to 1.021) and urbanicity (0.875, 95% CI 0.862 to 0.887), were far more important in explaining variations in admissions for ACSCs. People in deprived areas had a higher risk of being admitted in hospital for an incentivised ACSC condition.ConclusionSpatial analysis based on routinely collected data can be used to identify areas with high rates of potentially avoidable hospital admissions, providing valuable information for targeting resources and evaluating public health interventions. Our findings suggest that the QOF had a very small effect on reducing avoidable hospitalisation for incentivised conditions. Material deprivation and urbanicity were the strongest predictors of the variation in ACSC rates for all QOF incentivised conditions across England.
Association of occupational dust exposure with combined chronic obstructive pulmonary disease and pneumoconiosis: a cross-sectional study in China
Authors: Fan Yali , Xu Wenjing , Wang Yuanying , Wang Yiran , Yu Shiwen , Ye Qiao 
Published: September 2020

ObjectivesOccupational dust exposure may induce various lung diseases, including pneumoconiosis and chronic obstructive pulmonary disease (COPD). The features of combined COPD and pneumoconiosis have not been well described, and this may hamper the management. This study aimed to describe the prevalence and characteristics as well as the risk factors of the combined diseases.DesignA cross-sectional study.Setting and participants758 patients with pneumoconiosis were recruited at a single-medical centre. Of these, 675 patients with pneumoconiosis, including asbestosis, silicosis, coal workers’ pneumoconiosis and other pneumoconiosis, was eligible for analysis.Primary outcome measuresCOPD was diagnosed based on clinical features and/or history of exposure to risk factors and post bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio <0.7. Clinical data were collected from predesigned medical reports. The patients underwent both chest radiograph and high-resolution CT scans. Risk factors for combined COPD and pneumoconiosis were analysed using regression analysis.ResultsCOPD prevalence overall was 32.7% (221/675) and was the highest in silicosis (84/221) and coal workers’ pneumoconiosis (100/221). COPD prevalence increased with smoking pack-years, dust exposure duration and pneumoconiosis stage. Patients with combined diseases had lower body mass index, higher smoking index and worse pulmonary function. Risk factors for combined diseases included heavy smoking, silica or coal exposure and advanced pneumoconiosis. The interaction between dust exposure and smoking in COPD was also identified. The risk of combined COPD significantly increased with heavy smoking and silica or coal exposure (OR 5.49, 95% CI 3.04 to 9.93, p<0.001).ConclusionsCOPD is highly prevalent in patients with pneumoconiosis, especially patients with silicosis and coal workers’ pneumoconiosis. Occupational dust exposure as well as heavy smoking is associated with an increased risk of combined COPD and pneumoconiosis, which demands an effective preventive intervention.
Vacant lot to community garden conversion and crime in Milwaukee: a difference-in-differences analysis
Authors: Beam David R , Szabo Aniko , Olson Jared , Hoffman Lawrence , Beyer Kirsten M M 
Published: September 2020

BackgroundVacant lots generate the perception of neglect and are often opportunistic locations for crime. Evidence is building to suggest that greening vacant lots, especially through community engaged approaches, is associated with reductions in some types of crime.MethodsUsing a retrospective quasi-experimental approach, we compared the conversion of vacant lots into community gardens (n=53) with a group of matched control lots (n=159) to examine the effect of this intervention on police reported theft, violent and nuisance crime in Milwaukee, Wisconsin. Conversions often involved the addition of planter boxes to create a garden, and sometimes included benches, paths, works of art or other landscaping features. Public crime data were used to generate crime rates within 100 m and 250 m around each lot.ResultsViolent and nuisance crime rates are lower near treatment lots based on an unadjusted difference-in-differences analysis of means and two Poisson regression models. While no substantial effects were observed among theft crimes, the most consistent crime rate reductions were found among violent crime within 250 m, ranging between 3.7% and 6.4% across analyses.ConclusionsDespite the small number of interventions, community-driven vacant lot to garden conversions were associated with slight reductions in crime. Urban greening initiatives may be a promising strategy to reduce urban crime and warrant further study.