bluuebunny/crossref_metadata_2025_split huggingface dataset:
APPLICATION DIRECT METHOD CALCULUS OF VARIATION FOR KLEIN-GORDON FIELD
Authors: Saiman Saiman , Agustino Rinto , Hamdani Hamdani 
Published: October 2019

Klein-Gordon field is often used to study the dynamics of elementary particles. The Klein–Gordon equation was first considered as a quantum wave equation by Schrödinger in his search for an equation describing de Broglie waves. The equation was found in his notebooks from late 1925, and he appears to have prepared a manuscript applying it to the hydrogen atom. Yet, because it fails to take into account the electron's spin, the equation failed to predict the fine structure of the hydrogen atom, and overestimated the overall magnitude of the splitting pattern energy. This paper will describe in detail using the Direct Method of Calculus Variation as an alternative to solve the Klien-Gordon field equations. The Direct Method simplified the calculation because the variables are calculated and expressed in functional form of energy. The result of the calculation of Klien-Gordon Feld provided the existence of the minimizer, i.e. with and . Explicit form of the minimizer was calculated by the Ritz method through rows of convergent density
AIR POLLUTANT EMISSIONS IN BATAM: AN OVERVIEW
Authors: Triwinarko Andy , Kartikasari Dwi , Istardi Didi , Ghozali Syafei , Mulyaningtyas Dian 
Published: October 2019

This paper aims at providing high quality air pollutant emissions analysis, so that policy makers have reliable information in shaping environmental priorities. The study was conducted in Batam, a special economic zone that is packed by industries.Emissions of NOx, CO, SOx, PM10, and HC were estimated using the 2013 EMEP/EEA methods and those of COx were estimated using the 2006 Intergovernmental Panel on Climate Change (IPCC) guidelines, both were tier 2 methods where applicable. We found that powerplants, large-scale heavy industrymetals and mobile sources were important emission sources, while area sources such ashotels, hospitals, restaurants, universities, banks, malls, vehicle repairs, housings, gas stations, facilities under constructions, landfills, and electronics manufacturing companiescontributed much less significant to the total emissions. By mapping all sources, we found that the air pollution sources densely populated along the main streets. Conclusively, this paper recommends some measures to improve the overall air quality in Batam.
THE PHOTOCHEMISTRY OF CR(CO)6 IN HIGH PRESSURE LOW TEMPERATURE POLYMER MATRIX MONITORED BY FOURIER TRANSFORM INFRARED AND UV-VIS SPECTROSCOPY
Authors: W. Harun Farah 
Published: October 2019

The aim of this work is to develop a new type of polymer matrix which can be used to study the reactive intermediates produced from UV photolysis of metal carbonyl complexes measured with FTIR as well as UV-vis spectroscopy. The photochemistry of Cr(CO)6 impregnated in Teflon-AF polymer with the presence of N2, CH4 and even weak ligand i.e.Xe and He were conducted at extremely low temperature. Photolysis of Cr(CO)6 under N2 environment produces up to four carbonyl groups being replaced with the N2. Meanwhile, the photochemistry of Cr(CO)6 under Xe and CH4 produce the reactive complexes of Cr(CO)5(Xe) and Cr(CO)5(CH4)respectively. Teflon-AF was found to be the suitable matrix material as the –C–F– bond binds very weakly to the metal center.
PURIFICATION AND CHARACTERISATION OF FIBRINOLYTIC ENZYMES FROM ENDOPHYTIC FUNGI AND LIGNOSUS RHINOCERUS
Authors: Mohd Noor Zainon , Ahmad Mohd Sidek , Zainal Ariffin Zaidah 
Published: October 2019

Three enzymes FH3, S13 and LR1 from three different sources showed fibrinolytic activities. Two were from endophytic fungal cultures and one from the sclerotium of Lignosus rhinocerus mushroom (LR1). FH3, S13 cultures and LR1, the crude extract of the sclerotium were concentrated and purified by ammonium sulphate precipitation, ion-exchange chromatography and gel-filtration. The molecular weights of the FH3, S13 and LR1 purified enzymes were estimated to be approximately 34kDa, 34kDa and 10kDa, respectively. Maximum fibrinolytic activities were observed for FH3 at pH 7 and 30°C, S13 at pH 8 and 40°C and LR1 at pH 6 and 40°C. In our earlier paper we identified FH3 as Fusarium sp. and S13 as Penicilium citrinum.
BODY IMAGE PERCEPTION, BODY SHAPE CONCERN AND BODY SHAPE DISSATISFACTION AMONG UNDERGRADUATES STUDENTS
Authors: K. Kamaria, , M. Vikram, , R. Ayiesah, 
Published: October 2019

There are significant surge on body image concern among young adults globally. The negative body image eventually leads to body shape dissatisfaction (BSD) and consequently would cause unfavorable outcomes such as anxiety, depression, low-self-esteem and poor quality of life. The self-reported body mass index (BMI), Self-rating Body Silhouette and Body Shape Questionnaire (BSQ-16A) were used to identify relationship of body image perception, body shape concern with body shape dissatisfaction (BSD) among undergraduates’ students at Health Science Faculty UiTM, Malaysia. Majority of males and females were in normal category on body image perception with 64.7 % and 61 % respectively. About 79.4 % of male and 82.7 % female perceived their body weight as ideal body weight. On body shape concern, 67.6 % of male and 45.7 % of female were not concerned of their shape. Approximately 48.1 % of females were dissatisfied with their body shape and desire to become thinner contrary 44.1 % of male desire to become heavier. In addition increase in body shape concern lead decrease BSD. In view of their ignorance to achieve the desired body image and body shape concern may raise fear of unhealthy eating practices especially among female’s students. Thus, health awareness programs, health promotion, and health screening are to be necessitated among female university students to alleviate the potential risk of unhealthy eating behaviors.
Numerical Investigations of Pollutant Emissions From Novel Heavy-Duty Gas Turbine Burners Operated With Natural Gas
Authors: Pampaloni Daniele , Nassini Pier Carlo , Andreini Antonio , Facchini Bruno , Cerutti Matteo 
Published: October 2019

Abstract
A numerical investigation of pollutant emissions of a novel dry low-emissions burner for heavy-duty gas turbine applications is presented. The objective of this work is to develop and assess a robust and cost-efficient numerical setup for the prediction of NOx and CO emissions in industrial gas turbines and to investigate the pollutant formation mechanisms, thus supporting the design process of a novel low-emission burner. To this end, a comparison against experimental data, from a recent experimental campaign performed by BHGE in cooperation with University of Florence, has been exploited. In the first part of this work, a Reynolds-averaged Navier–Stokes (RANS) approach on both a simplified geometry and the complete domain is adopted to characterize the global flame behavior and validate the numerical setup. Then, unsteady simulations exploiting the scale adaptive simulation (SAS) approach have been performed to assess the prediction improvements that can be obtained with the unsteady modeling of the flame. For all simulations, the flamelet generated manifold (FGM) model has been used, allowing the reliable and cost-efficient application of detailed chemistry mechanisms in computational fluid dynamics (CFD) simulation. However, FGM typically faces issues predicting flame emissions, such as NOx and CO, due to the wide range of time scales involved, from turbulent mixing to pollutant species oxidation. Specific models are typically used to predict NOx emissions, starting from the converged flow-field and introducing additional transport equations. Also CO prediction, especially at part-load operating conditions could be an issue for flamelet-based model: in fact, as the load decreases and the extinction limit approaches, a superequilibrium CO concentration, which cannot be accurately predicted by FGM, appears in the exhaust gases. To overcome this issue, a specific CO-burn-out model, following the original idea proposed by Klarmann, has been implemented in ANSYS fluent. The model allows to decouple the effective CO oxidation term from the one computed by FGM, defining a postflame zone where the source term of CO is treated following the Arrhenius formulation. In order to support the design process, an indepth CFD investigation has been carried out, evaluating the impact of an alternative burner geometrical configuration on stability and emissions and providing detailed information about the main regions and mechanisms of pollutants production. The outcomes support the analysis of experimental results, allowing an indepth investigation of the complex flow-field and the flame-related quantities, which have not been measured during the tests.
Simple Contact Stiffness Model Validation for Tie Bolt Rotor Design With Butt Joints and Pilot Fits
Authors: Rimpel Aaron M. , Leopard Matthew 
Published: October 2019

Abstract
Tie bolt rotors for centrifugal compressors comprise multiple shaft components that are held together by a single tie bolt. The axial connections of these rotors—including butt joints, Hirth couplings, and Curvic couplings—exhibit a contact stiffness effect, which tends to lower the shaft bending frequencies compared to geometrically identical monolithic shafts. If not accounted for in the design stage, shaft bending critical speed margins can be compromised after a rotor is built. A previous paper had investigated the effect of tie bolt force on the bending stiffness of stacked rotor assemblies with butt joint interfaces, both with and without pilot fits. This previous work derived an empirical contact stiffness model and developed a practical finite element modeling approach for simulating the axial contact surfaces, which was validated by predicting natural frequencies for several test rotor configurations. The present work built on these previous results by implementing the same contact stiffness modeling approach on a real tie bolt rotor system designed for a high pressure centrifugal compressor application. Each joint location included two axial contact faces, with contact pressures up to five times higher than previously modeled, and a locating pilot fit. The free-free natural frequencies for different amounts of tie bolt preload force were measured, and the frequencies exhibited the expected stiffening behavior with increasing preload. However, a discontinuity in the data trend indicated a step-change increase in the contact stiffness. It was shown that this was likely due to one or more of the contact faces becoming fully engaged only after sufficient tie bolt force was applied. Finally, a design calculation was presented that can be used to estimate whether contact stiffness effects may be ignored, which could simplify rotor analyses if adequate contact pressure is used.
Longitudinal Trajectories of Children’s Physical Activity and Sedentary Behaviors on Weekdays and Weekends
Authors: Zhang Peng , Lee Jung Eun , Stodden David F. , Gao Zan 
Published: October 2019

Background: The objective was to examine changes of children’s time spent in sedentary, light physical activity, moderate to vigorous physical activity (MVPA), and estimated energy expenditure (EE) rates during weekdays and weekends across 3 years.Methods: An initial sample of 261 children’s (mean age = 7.81 y) 5-day physical activity and EE were assessed annually via accelerometry across 3 years using repeated-measures multivariate analysis of variance. The outcome variables were time spent in sedentary, light physical activity, MVPA, and kilocalories per day for weekdays and weekends.Results: A significant decrease in MVPA and EE occurred during weekdays across the 3 years (P = .01). Only the second-year data demonstrated an increase (+2.49 min) in weekend MVPA (P = .04). Children’s sedentary time during weekdays increased significantly in years 1 and 2 (P = .01), yet significantly decreased in the third year (−44.31 min). Children’s sedentary time during weekends significantly decreased in the first year (−27.31 min), but increased in the following 2 years (P = .01). Children’s light physical activity demonstrated a statistically significant increase in year 2 (+3.75 min) during weekdays (P = .05).Conclusions: Children’s MVPA and EE generally declined during weekdays but were maintained during weekends across a 3-year time span. Children may benefit most from weekday intervention strategies.
Sensitivity of a western Great Basin terminal lake to winter northeast Pacific storm track activity and moisture transport
Authors: Hatchett Benjamin J. , Boyle Douglas P. , Garner Chris B. , Kaplan Michael L. , Bassett Scott D. , Putnam Aaron E. 
Published: October 2019

ABSTRACT
Shorelines formed by terminal lakes record past changes in regional moisture budgets. In the western Great Basin of North America, winter precipitation accounts for nearly half of the annual total and is well correlated with northeast Pacific storm track activity and moisture transport. We evaluated these relationships and found that historical precipitation between 1910 and 2012 was better correlated to moisture transport (0.78, p &lt; 0.01) than to storm track activity (0.54, p &lt; 0.01) because moisture transport better captures dynamics associated with the Sierra Nevada rain shadow. We derived modern analogs of enhanced and reduced storm track activity and moisture transport from reanalysis products and used associated winter precipitation anomalies with these analogs as inputs to a coupled water balance and lake evaporation model of the Walker Lake basin. Simulated lake-level responses were compared with a radiocarbon-dated lakeshore chronology spanning the past 3700 yr. Wet analogs developed from winters in the 90th and 75th percentiles for storminess and moisture transport produced lake levels that exceeded estimated late Holocene highstands by 50 m. Dry analogs (10th and 25th percentiles) produced lake levels corresponding to Medieval megadrought lowstands. The twentieth century is shown to be as wet as any century in the past 3700 yr. Our results demonstrate the sensitivity of terminal lakes to winter season circulations and highlight the value of using moisture transport as a predictor of cool season precipitation and to evaluate how past or future changes in regional circulations will influence the water balance of dryland regions.
Perspectives on the paleolimnology of the late Eocene Florissant lake from diatom and sedimentary evidence at Clare’s Quarry, Teller County, Colorado, USA
Authors: Benson* Mary Ellen , Smith Dena M. , Spaulding Sarah A. 
Published: October 2019

ABSTRACT
The late Eocene Florissant Formation in central Colorado is a rich and diverse continental Lagerstätte yielding well-preserved fossil assemblages from lacustrine and fluvial facies. This investigation focused on the lacustrine facies at Clare’s Quarry and used biotic and abiotic evidence to characterize aspects of the lake and processes that resulted in the accumulation and preservation of the host rock and its fossils. Autecology of modern analogs representing the fossil diatom taxa was used to augment sedimentary data in characterizing the lake, propose peripheral habitats within the catchment area, and suggest a terrestrial source for mudstone units.
The sedimentary and stratigraphic record at the study site reveals a lake with sufficient depth to allow bottom waters to remain isolated and anoxic for long periods. Sediments that accumulated in the lake produced distinct lacustrine lithofacies that are interpreted as representing at least three modes of origin: stable lake, pyroclastic, and mud turbidite sedimentation. Slow, suspension settling of fine clays and volcanic ash into a moderately deep, stable lake resulted in laminated shales. These laminated shales contain frustules of diatoms from planktic and benthic lake habitats; diatoms transported into the lake from streams and wetlands; fish, mollusks, ostracods, and insects; and plants from marginal and upslope environments. Intermittent volcanic eruptions produced air-fall ash and granular tuff that accumulated as interbeds within the lake shales. Periods of stable lake sedimentation were frequently interrupted by rapid influxes of suspended fine clays, perhaps as mud-dominated turbidites that prograded into the lake at intervals of high runoff triggered by climatic, volcanic, or tectonic events.
A bit or a lot on the side? Observational study of the energy content of starters, sides and desserts in major UK restaurant chains
Authors: Muc Magdalena , Jones Andrew , Roberts Carl , Sheen Florence , Haynes Ashleigh , Robinson Eric 
Published: October 2019

ObjectivesOur objective was to examine the kilocalorie (kcal) content of starters, sides and desserts served in major UK restaurant chains, comparing the kcal content of these dishes in fast-food and full-service restaurants.DesignObservational study.SettingMenu and nutritional information provided online by major UK restaurant chains.MethodDuring October to November 2018, we accessed websites of restaurant chains with 50 or more outlets in the UK. Menu items that constituted starters, sides or desserts were identified and their kcal content was extracted. Accompanying beverages were not included. We used multilevel modelling to examine whether mean kcal content of dishes differed in fast-food versus full-service restaurants.Main outcome measuresThe mean kcal content of dishes and the proportion of dishes exceeding public health recommendations for energy content in a main meal (>600 kcal).ResultsA total of 1009 dishes (212 starters, 318 sides and 479 desserts) from 27 restaurant chains (21 full-service, 6 fast-food) were included. The mean kcal content of eligible dishes was 488.0 (SE=15.6) for starters, 397.5 (SE=14.9) for sides and 430.6 (SE=11.5) for desserts. The percentage of dishes exceeding 600 kcal was 26.4% for starters, 21.7% for sides and 20.5% for desserts. Compared with fast-food chains, desserts offered at full-service restaurants were on average more calorific and were significantly more likely to exceed 600 kcal.ConclusionsThe average energy content of sides, starters and desserts sold in major UK restaurants is high. One in four starters and one in five sides and desserts in UK chain restaurants exceed the recommended energy intake for an entire meal.
Reducing unnecessary vitamin testing in general practice: barriers and facilitators according to general practitioners and patients
Authors: Hofstede H. , van der Burg H.A.M. , Mulder B.C. , Bohnen A.M. , Bindels P.J.E. , de Wit N.J. , de Schepper E.I.T. , van Vugt S.F. 
Published: October 2019

ObjectiveThere has been an increase in testing of vitamins in patients in general practice, often based on irrational indications or for non-specific symptoms, causing increasing healthcare expenditures and medicalisation of patients. So far, there is little evidence of effective strategies to reduce this overtesting in general practice. Therefore, the aim of this qualitative study was to explore the barriers and facilitators for reducing the number of (unnecessary) vitamin D and B12laboratory tests ordered.Design and settingThis qualitative study, based on a grounded theory design, used semistructured interviews among general practitioners (GPs) and patients from two primary care networks (147 GPs, 195 000 patients). These networks participated in the Reducing Vitamin Testing in Primary Care Practice (REVERT) study, a clustered randomized trial comparing two de-implementation strategies to reduce test ordering in primary care in the Netherlands.ParticipantsTwenty-one GPs, with a maximum of 1 GP per practice who took part in the REVERT study, and 22 patients (who were invited by their GP during vitamin-related consultations) were recruited, from which 20 GPs and 19 patients agreed to participate in this study.ResultsThe most important factor hampering vitamin-test reduction programmes is the mismatch between patients and medical professionals regarding the presumed appropriate indications for testing for vitamin D and B12. In contrast, the most important facilitator for vitamin-test reduction may be updating GPs’ knowledge about test indications and their awareness of their own testing behaviour.ConclusionTo achieve a sustainable reduction in vitamin testing, guidelines with clear and uniform recommendations on evidence-based indications for vitamin testing, combined with regular (individual) feedback on test-ordering behaviour, are needed. Moreover, the general public needs access to clear and reliable information on vitamin testing. Further research is required to measure the effect of these strategies on the number of vitamin test requests.Trial registration numberWAG/mb/16/039555.
Web-based support for self-management strategies versus usual care for people with COPD in primary healthcare: a protocol for a randomised, 12-month, parallel-group pragmatic trial
Authors: Stenlund Tobias , Nyberg André , Lundell Sara , Wadell Karin 
Published: October 2019

IntroductionThe use of adequate self-management strategies for people with chronic obstructive pulmonary disease (COPD) may increase the level of physical activity (PA), improve health-related quality of life (HRQoL) and reduce healthcare use. Whether web-based support in addition to prompts (email and SMS) could be used to promote self-management strategies to facilitate behaviour change in people with COPD is not clear. This clinical trial aims to generate evidence on the effect of a web-based solution, the COPD Web, in a cohort of people with COPD in a primary healthcare context.Methods and analysisThe overall design is a pragmatic randomised controlled trial with preassessments and postassessments (3 and 12 months) and an implementation and user experience evaluation. People with a diagnosis of COPD, treated in primary healthcare will be eligible for the study. A total of 144 participants will be enrolled through advertisment or by healthcare professionals at included primary healthcare units and, after fulfilled baseline assessment, randomised to either control or intervention group. All participants will receive usual care, a pedometer and a leaflet about the importance of PA. Participants in the intervention will, in addition, get access to the COPD Web, an interactive self-managed website that aims to support people with COPD in self-management strategies. They will also continuously get support from prompts with a focus on behaviour change.The effect on participants’ PA, dyspnoea, COPD-related symptoms, HRQoL and health economics will be assessed using accelerometer and questionnaires. To identify enablers and barriers for the use of web-based support to change behaviour, semistructured interviews will be conducted in a subgroup of participants at the 3 months follow-up.Ethics and disseminationEthical approval has been received from the Regional Ethical Review Board in Umeå, Sweden. Dnr 2018-274 and dnr 2019-05572. Findings will be presented at conferences, submitted for publication in peer-reviewed journals and presented to the involved healthcare professionals, participants and patient organisations.Trial registration numberNCT03746873