bluuebunny/crossref_metadata_2025 huggingface dataset:
The Design of a Contactless Unregulated Power Converter for the Separated Modules
Authors: Zhou Yan , Sun Yu , Yang Ziwen
Published: August 2020

In the contactless unregulated power converter application with high output current, optimizing coil structures and using synchronous rectification are important for achieving high efficiency. This paper proposes a separated planar structure of coils to achieve the design goals and gives its equivalent circuit model. On the power transmitting pad, double coils are used to enhance the ability of the output power levels. In order to implement full-wave synchronous rectification (FWSR), the power receiving pad also adopts double coils. The power coils on both sides have similar structures to obtain a balance-induced voltage in each half of the switching period, and the principles of the optimal turn ratio in coils are discussed. Meanwhile, four typical self-driven coil structures are compared and analyzed. The effect of the coupling coefficient and load currents on the loss of the duty cycle is discussed. To satisfy the requirements of output voltage, the rules for selecting the minimum ferrite core are summarized. A 120 W unregulated intermediate bus converter is built. The whole system achieves 90.7% efficiency under all loading ranges, and the maximum efficiency of the system is 94.5% at a 3.5A load current.
Geometrical Optimization of Pump-As-Turbine (PAT) Impellers for Enhancing Energy Efficiency with 1-D Theory
Authors: Wang Longyan , Asomani Stephen Ntiri , Yuan Jianping , Appiah Desmond
Published: August 2020

This paper presents a multi-objective optimization strategy for pump-as-turbines (PAT), which relies on one-dimensional theory and analysis of geometrical parameters. In this strategy, a theoretical model, which considers all possible losses incurred (mainly by the components of pipe inlet, impeller and volute), has been put forward for performance prediction of centrifugal pumps operating as turbines (PAT). With the established mathematical relationship between the efficiency of PAT (both at pump and turbine mode) and the impeller controlling variables, the geometric optimization of the PAT impeller is performed with constant rotational speed. Specifically, the optimization data consist of 50 sets of impellers generated from Latin Hypercube Sampling method with its corresponding efficiencies calculated. Subsequently, the pareto-based genetic algorithm (PBGA) was adopted to optimize the geometic parameters of the impellers through the theoretical model. To validate the theoretical optimization results, the high-fidelity Computational Fluid Dynamics (CFD) simulation and the experimental data are employed for comparison of the PAT performance. The findings show that the efficiencies of both the pump and PAT optimized variables increased by 0.27% and 16.3% respectively under the design flow condition. Based on the one-dimensional theoretical optimization results, the geometry of the impeller is redesigned to suit both pump and PAT mode operations. It is concluded that the chosen design variables (b2, β1, β2, and z) have a significant impact on the PAT efficiency, which demonstrates that the optimization scheme proposed in this study is practicable.
Multi-Step Ahead Short-Term Load Forecasting Using Hybrid Feature Selection and Improved Long Short-Term Memory Network
Authors: Pei Shaoqian , Qin Hui , Yao Liqiang , Liu Yongqi , Wang Chao , Zhou Jianzhong
Published: August 2020

Short-term load forecasting (STLF) plays an important role in the economic dispatch of power systems. Obtaining accurate short-term load can greatly improve the safety and economy of a power grid operation. In recent years, a large number of short-term load forecasting methods have been proposed. However, how to select the optimal feature set and accurately predict multi-step ahead short-term load still faces huge challenges. In this paper, a hybrid feature selection method is proposed, an Improved Long Short-Term Memory network (ILSTM) is applied to predict multi-step ahead load. This method firstly takes the influence of temperature, humidity, dew point, and date type on the load into consideration. Furthermore, the maximum information coefficient is used for the preliminary screening of historical load, and Max-Relevance and Min-Redundancy (mRMR) is employed for further feature selection. Finally, the selected feature set is considered as input of the model to perform multi-step ahead short-term load prediction by the Improved Long Short-Term Memory network. In order to verify the performance of the proposed model, two categories of contrast methods are applied: (1) comparing the model with hybrid feature selection and the model which does not adopt hybrid feature selection; (2) comparing different models including Long Short-Term Memory network (LSTM), Gated Recurrent Unit (GRU), and Support Vector Regression (SVR) using hybrid feature selection. The result of the experiments, which were developed during four periods in the Hubei Province, China, show that hybrid feature selection can improve the prediction accuracy of the model, and the proposed model can accurately predict the multi-step ahead load.
Development and Performance Investigation of an Inflatable Solar Drying Technology for Oyster Mushroom
Authors: Van Hung Nguyen , Fuertes Lei Anne , Balingbing Carlito , Paulo Roxas Ampy , Tala Marvin , Gummert Martin
Published: August 2020

We developed an inflatable solar dryer for mushroom drying, which was adapted from the Solar Bubble DryerTM originally designed for paddy drying. The improved dryer with an added perforated elevated floor ensured the quality without any requirement of mixing or turning of the mushrooms during drying. Its drying performance and economic feasibility were evaluated through determination of the drying parameters including moisture content (MC) reduction, mushroom quality, energy efficiency, greenhouse gas emissions, and cost-benefits ratio. Mushroom MC was reduced from 90% down to 40–60% within 2–4 h, corresponding to the drying rate at this stage of 10–20% h−1. At the next stage, it took about 4–6 h corresponding to a drying rate of 2–10% h−1 to reach the required product MC of 8–10%. The color of the dried mushrooms still remained white-cream. The drying process required 4.57 MJ, emitted 0.33 kg CO2e, and required an input cost of 1.86 $US kg of dry product. For the specific case in the Philippines, this can generate a net profit of 468–1468 $US−1 year−1 and the investment will break even in 1.3–4.0 years corresponding to the selling price of dry mushroom of 10–12 $US kg−1. The study developed a solution to improve the solar bubble dryer and verified its drying process for mushroom drying at farm scale. It would add a significant value to farmers’ income as well as a diversified source of nutrient-rich food.
Voltage Transients Mitigation in the DC Distribution Network of More/All Electric Aircrafts
Authors: Rigogiannis Nick , Voglitsis Dionisis , Jappe Tiago , Papanikolaou Nick
Published: August 2020

The objective of this paper is to present a power conversion system, based on a bidirectional DC/DC converter, along with a supercapacitor bank, that mitigates the voltage transients that occur on the DC distribution network of More/All Electric Aircrafts. These transients, such as voltage sags and swells appear on the DC buses of on-board microgrids, mainly due to load variations and are classified according to the aircrafts electric power system standards. First, we shortly describe an aircraft distribution network, that is applicable to the most common actual aircraft architectures, then we present the proposed system, along with the bidirectional DC/DC converter design, the control technique and the supercapacitor bank sizing. Finally, we present simulation and experimental results that support the effectiveness of the proposed system to effectively compensate voltage transients, supporting the DC buses in dynamic conditions. Concluding, the proposed system provides high power quality and compliance with the respective power quality standards for aircraft microgrids.
Indoor and Outdoor Design in Healthcare Environments: The Employees’ Views in the General University Hospital of Alexandroupolis, Greece
Authors: Karanikola Paraskevi , Andrea Veronika , Tampakis Stilianos , Tsolakidou Anastasia
Published: August 2020

Healthcare environments should be designed and operate as healing places for all their users. Therefore, the design of outdoor and indoor spaces, has to be oriented towards distressing solutions. The employees’ occupational stress affects their feelings and in turn their services they provide. Thus, this study aimed at the evaluation of the General University Hospital of Alexandroupolis, Greece according to its employees’ views. With the use of two step cluster analysis and the hierarchical cluster analysis, important findings were derived, concerning the interior and landscape design of the healthcare environment. The hospital indoor and outdoor spaces were investigated in relation with environmental parameters and psychological effects on their users. The results have shown a lack of the appropriate green spaces—even though their beneficial role was acknowledged—and marginal satisfaction with available spaces. Conclusively, it should be noted that there is still room for improvements in both interior and outdoor premises of the hospital to reduce stress levels, especially for its nursing staff.
The Development and Use of Isoscapes to Determine the Geographical Origin of Quercus spp. in the United States
Authors: Watkinson Charles , Gasson Peter , Rees Gareth , Boner Markus
Published: August 2020

The stable isotope ratios of oxygen, hydrogen, carbon and sulfur from extracted wood of 87 samples of oaks from the United States were analysed. Relationships with climate variables and the stable isotope ratios of the 69 training dataset samples were investigated to a monthly resolution using long-term monthly mean climate data from NASA and the University of East Anglia’s Climate Research Unit, in conjunction with forecast data for hydrogen and oxygen isotope ratios in precipitation. These relationships were used to construct model isoscapes for oxygen, hydrogen, carbon and sulfur for US oak with the aim of using them to forecast isotopic patterns in areas that were not sampled and predict values in samples not used to construct the models. The leading predictors for isoscape generation were oxygen isotope ratios in January precipitation for oak oxygen isotope ratios, hydrogen isotope ratios in July precipitation for oak hydrogen isotope ratios, water vapour in April for carbon isotope ratios, and reflected shortwave radiation in March in combination with sulfate concentration in May for oak sulfur isotopes. The generated isoscapes can be used to show regions an unknown sample may have originated from with a resolution dependent on the rarity of the stable isotope signature within the United States. The models were assessed using the data of 18 samples of georeferenced oak. The assessment found that 100% of oxygen, 94% of hydrogen, 78% of carbon, and 94% of sulfur isotope ratios in the 18 test dataset samples fell within two standard deviations of the isoscape models. Using the results of the isoscapes in combination found that there were 4/18 test samples which did not fall within two standard deviations of the four models, this is largely attributed to the lower predictive power of the carbon isoscape model in conjunction with high local variability in carbon isotope ratios in both the test and training data. The method by which this geographic origin method has been developed will be useful to combat illegal logging and to validate legal supply chains for the purpose of good practice due diligence.
Growth and Nutrient Acclimation of Evergreen Oak Seedlings Infected with Boletus reticulatus in Infertile Colluvial Soil in Warm Temperate Monsoon Asia: Evaluation of Early Growth
Authors: Kayama Masazumi
Published: August 2020

Soil erosion after harvesting of forest plantations can create infertile colluvial soil, therefore, seedlings used for site reforestation should be equipped against nutrient-poor edaphic conditions. The oak genus is a suitable candidate for such reforestation efforts. Oak is an ectomycorrhizal (ECM) tree genus known to grow under infertile environments. In this study, the initial stage of tree growth in three species of oak seedlings inoculated with a spore suspension of ECM fungus was monitored to evaluate the acceleration of seedling growth and nutrient uptake. I selected Quercus acuta Thunb., Quercus glauca Thunb., and Quercus salicina Blume, as these are common, evergreen, broad-leaved woody species commonly found in Southwestern Japan. The seedlings were inoculated with Boletus reticulatus and planted in infertile colluvial soils collected from a site that had undergone soil erosion. I also compared the ecophysiological characteristics of the potted seedlings planted in colluvial soil and normal forest soil. After six months of cultivation, Q. glauca with the ECM showed the highest growth rate in the fertile forest soil and had leaves with a higher nutrient content. In contrast, root dry mass increased slightly in Q. acuta and Q. salicina planted in colluvial soil. In all species, the seedling’s ECM colonization rate in colluvial soil was lower than that in forest soil, yet the increase in nutrient uptake in the former was not obvious. The contents of K and Ca in the roots of Q. acuta and Q. salicina increased with B. reticulatus infection. I concluded that the inoculation with a B. reticulatus spore suspension effectively accelerated the growths in all three Quercus species. Q. glauca favored a fertile environment, and Q. acuta and Q. salicina suitably acclimated to both soil types. Thus, these species were selected as potential future candidates for reforestation in such eroded sites.
By-Products in the Malting and Brewing Industries—Re-Usage Possibilities
Authors: Karlović Andrea , Jurić Anita , Ćorić Nevena , Habschied Kristina , Krstanović Vinko , Mastanjević Krešimir
Published: August 2020

Beer production includes the formation of different by-products such as wastewater, spent grains, spent hops, and yeast. In addition to these well-known by-products, it is necessary to mention germ/rootlets, which also remain after the malting process. Given that a huge amount of beer is produced annually worldwide, by-products are available in large quantities throughout the year. Spent grains, spent hops, and spent yeasts are high-energy raw materials that possess a great potential for application in the branch of biotechnology, and the food industry, but these by-products are commonly used as livestock feed, disposed of in the fields, or incinerated. Breweries by-products can be utilized for microalgae production, biofuel production, extraction of proteins, polyphenolic, antioxidative substances, etc. This paper aims to address each of these by-products with an emphasis on their possible application in biotechnology and other industries.
Navigating the Wildfire–Pandemic Interface: Public Perceptions of COVID-19 and the 2020 Wildfire Season in Arizona
Authors: Edgeley Catrin M. , Burnett Jack T.
Published: August 2020

COVID-19 has complicated wildfire management and public safety for the 2020 fire season. It is unclear whether COVID-19 has impacted the ability of residents in the wildland–urban interface to prepare for and evacuate from wildfire, or the extent to which residents feel their household’s safety has been affected. Several areas with high wildfire risk are also experiencing record numbers of COVID-19 cases, including the state of Arizona in the southwestern United States. We conducted a mixed-mode survey of households in close proximity to two recent wildfires in rural Arizona to better understand whether residents living in the wildland–urban interface perceive COVID-19 as a factor in wildfire safety. Preliminary data suggest that the current challenges around collective action to address wildfire risk may be further exacerbated due to COVID-19, and that the current pandemic has potentially widened existing disparities in household capacity to conduct wildfire risk mitigation activities in the wildland–urban interface. Proactive planning for wildfire has also increased perceived ability to practice safe distancing from others during evacuation, highlighting the benefits that household planning for wildfire can have on other concurrent hazards. Parallels in both the wildfire and pandemic literature highlight vast opportunities for future research that can expand upon and advance our findings.
Multi-Extraction and Quality of Protein and Carrageenan from Commercial Spinosum (Eucheuma denticulatum)
Authors: Naseri Alireza , Jacobsen Charlotte , Sejberg Jimmy J. P. , Pedersen Tommy Ewi , Larsen Jan , Hansen Karin Meyer , Holdt Susan L.
Published: August 2020

Seaweeds contain many valuable compounds that can be used in the food industry. Carrageenan is a polysaccharide which has been extracted from seaweed for centuries and is used as a texturizer in food and non-food products. However, seaweeds contain compounds other than carrageenan, such as proteins, which could also be extracted. This extraction should be done without compromising the industrial scale carrageenan extraction yield and quality. This study aimed at up-stream protein extraction from red seaweed Eucheuma denticulatum by using of an optimized enzyme-assisted extraction, including of an aqueous/enzymatic treatment followed by alkaline extraction, and then the commercial carrageenan extraction. The protein extraction efficiency of four enzymes was evaluated including Celluclast® 1.5L, Shearzyme® 500 L, Alcalase® 2.4 L FG and Viscozyme® L at a concentration of 0.0, 0.1, 0.2 and 0.4% (w/w). To avoid detrimental effects on carrageenan, all the experiments were performed at pH 7 at room temperature. The results showed that 0.2% w/w Alcalase® or Viscozyme® added individually achieved the highest protein extraction efficiencies (59 and 48%, respectively) at pH 7 and room temperature (p < 0.05). Determination of the most common carrageenan quality parameters indicated that using any of these enzymes had no negative effect on the carrageenan yield and quality.
Development of Dynamic Model for Real-Time Monitoring of Ripening Changes of Kimchi during Distribution
Authors: Kim Ji-Young , Kim Byeong-Sam , Kim Jong-Hoon , Oh Seung-Il , Koo Junemo
Published: August 2020

This study describes the development of a method for predicting the ripening of Kimchi according to temperature to provide information on how the ripening of Kimchi changes during distribution. Various Kimchi quality factors were assessed according to temperature and time. The acidity (lactic acid %) was selected as a good freshness index, as it is dependent on temperature and correlates strongly with the sensory quality evaluation. Moreover, it is easy to measure and reproducible in the field. The maximum value of acidity in the stationary phase was observed to increase with the storage temperature. A predictive model was developed using the Baranyi and Roberts and Polynomial models to mathematically predict the acidity. A method using the mean kinetic temperature (MKT) was proposed. The accuracy of the model using the MKT was high. It was confirmed that there is no great variation in the maximum acidity, as MKT does not change much if the temperature changes in the stationary phase where the maximum acidity is constant. This study provides important information about the development of models to predict changes in food quality index under fluctuating temperature environments. The developed kinetic model uniquely treated the quality index at the stationary phase as a function of MKT. The predictions using the food temperature histories could help suppliers and consumers make a reasonable decision on the sales, storage, and consumption of foods. The developed model could be applied to other products such as beef for which the quality index at the stationary phase also changes with temperature histories.
X-ray Flux and Spectral Variability of Blazar H 2356-309
Authors: Wani Kiran A. , Gaur Haritma
Published: August 2020

We present the results of timing and spectral analysis of the blazar H 2356-309 using XMM-Newton observations. This blazar is observed during 13 June 2005–24 December 2013 in total nine observations. Five of the observations show moderate flux variability with amplitude 1.7–2.2%. We search for the intra-day variability timescales in these five light curves, but did not find in any of them. The fractional variability amplitude is generally lower in the soft bands than in the hard bands, which is attributed to the energy dependent synchrotron emission. Using the hardness ratio analysis, we search for the X-ray spectral variability along with flux variability in this source. However, we did not find any significant spectral variability on intra-day timescales. We also investigate the X-ray spectral curvature of blazar H 2356-309 and found that six of our observations are well described by the log parabolic model with α = 1.99–2.15 and β = 0.03–0.18. Three of our observations are well described by power law model. The break energy of the X-ray spectra varies between 1.97–2.31 keV. We investigate the correlation between various parameters that are derived from log parabolic model and their implications are discussed.
Carrot Anthocyanins Genetics and Genomics: Status and Perspectives to Improve Its Application for the Food Colorant Industry
Authors: Iorizzo Massimo , Curaba Julien , Pottorff Marti , Ferruzzi Mario G. , Simon Philipp , Cavagnaro Pablo F.
Published: August 2020

Purple or black carrots (Daucus carota ssp. sativus var. atrorubens Alef) are characterized by their dark purple- to black-colored roots, owing their appearance to high anthocyanin concentrations. In recent years, there has been increasing interest in the use of black carrot anthocyanins as natural food dyes. Black carrot roots contain large quantities of mono-acylated anthocyanins, which impart a measure of heat-, light- and pH-stability, enhancing the color-stability of food products over their shelf-life. The genetic pathway controlling anthocyanin biosynthesis appears well conserved among land plants; however, different variants of anthocyanin-related genes between cultivars results in tissue-specific accumulations of purple pigments. Thus, broad genetic variations of anthocyanin profile, and tissue-specific distributions in carrot tissues and organs, can be observed, and the ratio of acylated to non-acylated anthocyanins varies significantly in the purple carrot germplasm. Additionally, anthocyanins synthesis can also be influenced by a wide range of external factors, such as abiotic stressors and/or chemical elicitors, directly affecting the anthocyanin yield and stability potential in food and beverage applications. In this study, we critically review and discuss the current knowledge on anthocyanin diversity, genetics and the molecular mechanisms controlling anthocyanin accumulation in carrots. We also provide a view of the current knowledge gaps and advancement needs as regards developing and applying innovative molecular tools to improve the yield, product performance and stability of carrot anthocyanin for use as a natural food colorant.
Retrospective Analysis Shows That Most RHDV GI.1 Strains Circulating Since the Late 1990s in France and Sweden Were Recombinant GI.3P–GI.1d Strains
Authors: Abrantes Joana , Lopes Ana M. , Lemaitre Evelyne , Ahola Harri , Banihashem Fereshteh , Droillard Clément , Marchandeau Stéphane , Esteves Pedro J. , Neimanis Aleksija , Le Gall-Reculé Ghislaine
Published: August 2020

Recombination is one of the major sources of genetic variation in viruses. RNA viruses, such as rabbit hemorrhagic disease virus (RHDV), are among the viruses with the highest recombination rates. Several recombination events have been described for RHDV, mostly as a consequence of their genomic architecture. Here, we undertook phylogenetic and recombination analyses of French and Swedish RHDV strains from 1994 to 2016 and uncovered a new intergenotypic recombination event. This event occurred in the late 1990s/early 2000s and involved nonpathogenic GI.3 strains as donors for the nonstructural part of the genome of these recombinants, while pathogenic GI.1d strains contributed to the structural part. These GI.3P–GI.1d recombinant strains did not entirely replace GI.1d (nonrecombinant) strains, but became the dominant strains in France and Sweden, likely due to a fitness advantage associated with this genomic architecture. GI.3P–GI.1d (P stands for polymerase) strains persisted until 2013 and 2016 in Sweden and France, respectively, and cocirculated with the new genotype GI.2 in France. Since strains from the first GI.2 outbreaks were GI.3P–GI.2, we hypothesize that GI.3P–GI.1d could be the parental strain. Our results confirm the outstanding recombination ability of RHDV and its importance in the evolution of lagoviruses, which was only revealed by studying complete genomic sequences.
Centromeres under Pressure: Evolutionary Innovation in Conflict with Conserved Function
Authors: Balzano Elisa , Giunta Simona
Published: August 2020

Centromeres are essential genetic elements that enable spindle microtubule attachment for chromosome segregation during mitosis and meiosis. While this function is preserved across species, centromeres display an array of dynamic features, including: (1) rapidly evolving DNA; (2) wide evolutionary diversity in size, shape and organization; (3) evidence of mutational processes to generate homogenized repetitive arrays that characterize centromeres in several species; (4) tolerance to changes in position, as in the case of neocentromeres; and (5) intrinsic fragility derived by sequence composition and secondary DNA structures. Centromere drive underlies rapid centromere DNA evolution due to the “selfish” pursuit to bias meiotic transmission and promote the propagation of stronger centromeres. Yet, the origins of other dynamic features of centromeres remain unclear. Here, we review our current understanding of centromere evolution and plasticity. We also detail the mutagenic processes proposed to shape the divergent genetic nature of centromeres. Changes to centromeres are not simply evolutionary relics, but ongoing shifts that on one side promote centromere flexibility, but on the other can undermine centromere integrity and function with potential pathological implications such as genome instability.
Combined Use of 3D Metric Survey and GPR for the Diagnosis of the Trapezophoros with Two Griffins Attacking a Doe of Ascoli Satriano (Foggia, Italy)
Authors: Cozzolino Marilena , Di Meo Andrea , Gentile Vincenzo , Mauriello Paolo , Zullo Enza
Published: August 2020

Protection and conservation are not feasible without a deeper knowledge of the cultural heritage of the subject of intervention. A careful analysis of documentation, a detailed visual inspection of surfaces, and a systematic diagnosis of the inner properties are the basis for planning preventive strategies of restoration. Digital noninvasive techniques represent an advantageous tool with useful outputs to estimate the state of health of cultural heritage in order to minimize the progress of degradation. This paper deals with a 3D metric survey through photogrammetry and ground-penetrating radar (GPR) tests applied to the study of the trapezophoros with two griffins attacking a doe of Ascoli Satriano, a masterpiece of ancient art that needs to be protected. This work provided information on both visible and hidden defects, such as numerous cracks that affect the sculpture.
Innovative Characterization of Particulate Matter Deposited on Urban Vegetation Leaves through the Application of a Chemical Fractionation Procedure
Authors: Ristorini Martina , Baldacchini Chiara , Massimi Lorenzo , Sgrigna Gregorio , Calfapietra Carlo
Published: August 2020

In this study, we have evaluated the efficiency of a chemical fractionation procedure for the characterization of both the water-soluble and the insoluble fraction of the main elemental components of particulate matter (PM) deposited on urban leaves. The proposed analytical approach is based on the chemical analysis of leaf washing solutions and membrane filters used for their filtration. The ionic concentration of leaf washing solutions was compared with their electrical conductivity, making it a valuable proxy for the quantification of the water-soluble and ionic fraction of leaf deposited PM. The chemical composition of both the water-soluble and the insoluble fraction of PM, resulting from this fractionation procedure, was compared with results obtained by scanning electron microscopy coupled with energy-dispersed X-Rays spectroscopy (SEM/EDX) and processed through chemometrics. Results obtained proved that the proposed approach is able to provide an estimation of total leaf deposited PM and it is highly reliable for the evaluation of the emission impact of different PM sources, being able to increase the selectivity of PM elemental components as specific source tracers; consequently providing useful information also for the assessment of human health risks.
Risk Perception and Depression in Public Health Crises: Evidence from the COVID-19 Crisis in China
Authors: Ding Yubin , Xu Junling , Huang Sisi , Li Peipei , Lu Cuizhen , Xie Shenghua
Published: August 2020

Background: Scant attention has been paid to how risk perceptions of public health crises may affect people’s mental health. Aims: The aims of this study are to (1) construct a conceptual framework for risk perception and depression of people in public health crises, (2) examine how the mental health of people in the crisis of Coronavirus Disease 2019 (COVID-19) is affected by risk perception and its associated factors, including distance perception of the crisis and support of prevention and control policies, and (3) propose policy recommendations on how to deal with psychological problems in the current COVID-19 crisis. Methods: Online questionnaire survey was implemented. A total of 6373 people visited the questionnaire online, 1115 people completed the questionnaire, and the number of valid questionnaires was 1081. Structural equation modeling was employed for data analysis. Results: Risk perception and its associated factors significantly affect the mental health of people in public health crises. Specifically, (1) distance perception of public health crises is negatively associated with depression among people, (2) affective risk perception is positively associated with depression of people in public health crises, (3) cognitive risk perception is negatively associated with depression of people in public health crises, and (4) support of prevention and control policies is negatively associated with depression of people in public health crises. Conclusion: The findings of this study suggest that risk perception plays an important role in affecting the mental health of people in a public health crisis. Therefore, health policies aiming to improve the psychological wellbeing of the people in a public health crisis should take risk perception into consideration.
Is Exercise the Best Medicine during a COVID-19 Pandemic? Comment on Constandt, B.; Thibaut, E.; De Bosscher, V.; Scheerder, J.; Ricour, M.; Willem, A. Exercising in Times of Lockdown: An Analysis of the Impact of COVID-19 on Levels and Patterns of Exercise among Adults in Belgium. Int. J. Environ. Res. Public Health 2020, 17, 4144
Authors: Hew-Butler Tamara , Smith-Hale Valerie , Van Sumeren Matthew , Sabourin Jordan , Levy Phillip
Published: August 2020

From Constandt et al.’s survey of 13,515 Belgium respondents, regular physical activity can be successfully initiated and sustained during a lockdown, with appropriate social distancing measures. Documentation that 77% of highly active people and 58% of low active people exercised as much or more following the institution of a nationwide lockdown was impressive, given that the cases of COVID-19 were accelerating at that time. The Belgian government’s central promotion of exercise, to boost both the mental and physical health of the population, likely contributed to the health, tolerance, and ultimate success of lockdown. In this commentary, we wish to pose a follow-up query which highlights the potential detrimental effects of intense exercise (competition) performed without social distancing measures. The proposed graphical abstract elucidates these possible risks, in contrast to the favorable results outlined in Constandt et al.’s study.
Challenges in Navigating the Health Care System: Development of an Instrument Measuring Navigation Health Literacy
Authors: Griese Lennert , Berens Eva-Maria , Nowak Peter , Pelikan Jürgen M. , Schaeffer Doris
Published: August 2020

Due to their rapid expansion and complexity, it is increasingly difficult for patients to orient themselves in health care systems. Therefore, patients require a high degree of health literacy, or more precisely, navigation health literacy (HL-NAV). The actual extent of HL-NAV of patients and citizens is still largely unknown due to the lack of adequate measurement instruments. Thus, within the new international Health Literacy Population Survey 2019 (HLS19), one aim was to develop a suitable instrument for measuring HL-NAV in the HLS19 the HL-NAV-HLS19. The item development was conducted by an international working group within the HLS19 Consortium led by the first and last authors. Methodologically, it is based on a scoping literature review, development of a conceptual framework for HL-NAV, and first item formation, as well as an evaluation by experts, stakeholders, focus groups, pre-test interviews, and continuously feedback from the HLS19 Consortium. HL-NAV was defined as the ability to access, understand, appraise, and apply information on navigational issues, drawing on ten selected publications and the health literacy definition of the HLS-EU Consortium. Main tasks of HL-NAV at the system, organization, and interaction level were identified, to which first related items were assigned. Based on the feedback from experts, the focus group discussions, and the HLS19 Consortium, the instrument was slightly revised. Finally, twelve items proved to be feasible in the pre-test. The instrument will be used for the first time in the HLS19 survey and will provide first data on HL-NAV in general populations for the countries participating in HLS19. It is suited for cross-country comparisons and monitoring, as well as for intervention development. However, the instrument should be translated into and validated in further languages and countries for population samples.
The Motor and Leisure Time Conditioning of Young Table Tennis Players’ Physical Fitness
Authors: Pluta Beata , Galas Szymon , Krzykała Magdalena , Andrzejewski Marcin
Published: August 2020

The purpose of the study was to assess the association between physical fitness and the lifestyle determinants of elite junior table tennis players. The basic anthropometric characteristics (body height and body weight) were collected of 87 Polish table tennis players (girls, n = 38 and boys, n = 49, at different stages of sport training, targeted and specialized) aged 11–17 years. The level of special fitness tests from the Table Tennis Specific Battery Test were used, assessing reaction speed and displacement speed. All eight International Physical Fitness Test trials were also used to determine the level of general fitness of the participants. Selected questions from the Health Behaviour in School-Aged Children questionnaire were asked to measure factors associated with leisure time. The findings confirm a relationship between sedentary forms of leisure time activity and the training of young players at the targeted stage (Z = −2.93, p = 0.003 school days and Z = −2.12, p = 0.034 days off). Moreover, competitors with longer training experience more often chose active forms of spending free time. Knowledge of the global physical activity undertaken by young athletes during their leisure time provides a better understanding of their individual needs and may help young table tennis players to succeed at a world-class level in the future.
Selfitis Behavior: Assessing the Italian Version of the Selfitis Behavior Scale and Its Mediating Role in the Relationship of Dark Traits with Social Media Addiction
Authors: Monacis Lucia , Griffiths Mark D. , Limone Pierpaolo , Sinatra Maria , Servidio Rocco
Published: August 2020

Research on selfie-related behavior has recently flourished. The present study expands theoretical and empirical work on phenomenon by assessing the psychometric properties of the Selfitis Behavior Scale among an Italian sample and by examining its unexplored mediating role in the relationships between dark triad traits and social media addiction. A total of 490 participants (53.1% females) completed a self-report survey including socio-demographics, the Selfitis Behavior Scale (SBS), the Short Dark Triad Scale (SD3), and the Bergen Social Media Addiction Scale (BSMAS). Results showed the SBS had a five-factor structure with good psychometrics properties in terms of reliability coefficients and measurement invariance across gender. In addition, findings from the path model supported the mediating role of selfitis behavior in the relationships of narcissism and psychopathy with social media addiction. Machiavellianism was found to be unrelated to selfitis behavior and social media addiction. The model shed light into the previous inconsistent findings on the associations between dark triad traits and social media addiction by taking into account the key role of selfitis behavior as an underlying mechanism. The findings may explain individual differences in personality traits associated with co-dependence (i.e., the combination of the dependence on self and others and social media addiction).
Exercise- and Cold-Induced Human PGC-1α mRNA Isoform Specific Responses
Authors: Larson Camille , Opichka Megan , McGlynn Mark L. , Collins Christopher W. , Slivka Dustin
Published: August 2020

Cold exposure in conjunction with aerobic exercise stimulates gene expression of PGC-1α, the master regulator of mitochondrial biogenesis. PGC-1α can be expressed as multiple isoforms due to alternative splicing mechanisms. Among these isoforms is NT-PGC-1α, which produces a truncated form of the PGC-1α protein, as well as isoforms derived from the first exon of the transcript, PGC-1α-a, PGC-1α-b, and PGC-1α-c. Relatively little is known about the individual responses of these isoforms to exercise and environmental temperature. Therefore, we determined the expression of PGC-1α isoforms following an acute bout of cycling in cold (C) and room temperature (RT) conditions. Nine male participants cycled for 1h at 65% Wmax at −2 °C and 20 °C. A muscle biopsy was taken from the vastus lateralis before and 3h post-exercise. RT-qPCR was used to analyze gene expression of PGC-1α isoforms. Gene expression of all PGC-1α isoforms increased due to the exercise intervention (p < 0.05). Exercise and cold exposure induced a greater increase in gene expression for total PGC-1α (p = 0.028) and its truncated isoform, NT-PGC-1α (p = 0.034), but there was no temperature-dependent response in the other PGC-1α isoforms measured. It appears that NT-PGC-1α may have a significant contribution to the reported alterations in the exercise- and temperature-induced PGC-1α response.
A System Dynamics Simulation Applied to Healthcare: A Systematic Review
Authors: Davahli Mohammad Reza , Karwowski Waldemar , Taiar Redha
Published: August 2020

In recent years, there has been significant interest in developing system dynamics simulation models to analyze complex healthcare problems. However, there is a lack of studies seeking to summarize the available papers in healthcare and present evidence on the effectiveness of system dynamics simulation in this area. The present paper draws on a systematic selection of published literature from 2000 to 2019, in order to form a comprehensive view of current applications of system dynamics methodology that address complex healthcare issues. The results indicate that the application of system dynamics has attracted significant attention from healthcare researchers since 2013. To date, articles on system dynamics have focused on a variety of healthcare topics. The most popular research areas among the reviewed papers included the topics of patient flow, obesity, workforce demand, and HIV/AIDS. Finally, the quality of the included papers was assessed based on a proposed ranking system, and ways to improve the system dynamics models’ quality were discussed.
Gender Differences in Kinematic Parameters of Topspin Forehand and Backhand in Table Tennis
Authors: Bańkosz Ziemowit , Winiarski Sławomir , Malagoli Lanzoni Ivan
Published: August 2020

Background: The identification of gender differences in kinematics and coordination of movement in different body segments in sports may improve the training process by emphasizing the necessity of its differentiation, and consequently individualization, developing, and improving the technique in women and men. Indicating differences can also help in determining the risk of injury in order to prevent from them by diversifying training programs. However, there is no information regarding this problem in the existing literature pertaining to table tennis. Therefore, the aim of the study was to evaluate the differences in the values of selected angular and kinematic parameters during topspin forehand and topspin backhand shots between male and female table tennis players. Methods: Six male and six female advanced table tennis players performed topspin forehand and topspin backhand shots, both receiving a backspin ball. The angular parameters in four events (ready position, backswing, maximum acceleration, and forward) at chosen joints as well as the maximal acceleration of the playing hand were measured, using the myoMotion system, and were compared between male and female players. Results: Significant differences (p ≤ 0.05) were found in the magnitude of angular parameters and maximum hand acceleration between men and women. The movement pattern of topspin strokes performed by men takes into account, more than that in the case of women, movements that use large muscle groups and large joints (hip joints, trunk joints, shoulder joints in extension, and flexion). The difference in the values of maximal acceleration reached almost 50 m/s2 in topspin forehand (p < 0.01) and 20 m/s2 in backhand (p < 0.01). Conclusions: Differentiation of movement patterns can be a manifestation of movement optimization due to anthropological differences and limitations. The differences in the values of maximal acceleration suggest that women could use both sides to perform a topspin attack against the backspin ball, while men should seek opportunities to make a stronger shot with a forehand topspin.
Influence of a Six-Week Swimming Training with Added Respiratory Dead Space on Respiratory Muscle Strength and Pulmonary Function in Recreational Swimmers
Authors: Szczepan Stefan , Danek Natalia , Michalik Kamil , Wróblewska Zofia , Zatoń Krystyna
Published: August 2020

The avoidance of respiratory muscle fatigue and its repercussions may play an important role in swimmers’ health and physical performance. Thus, the aim of this study was to investigate whether a six-week moderate-intensity swimming intervention with added respiratory dead space (ARDS) resulted in any differences in respiratory muscle variables and pulmonary function in recreational swimmers. A sample of 22 individuals (recreational swimmers) were divided into an experimental (E) and a control (C) group, observed for maximal oxygen uptake (VO2max). The intervention involved 50 min of front crawl swimming performed at 60% VO2max twice weekly for six weeks. Added respiratory dead space was induced via tube breathing (1000 mL) in group E during each intervention session. Respiratory muscle strength variables and pulmonary and respiratory variables were measured before and after the intervention. The training did not increase the inspiratory or expiratory muscle strength or improve spirometric parameters in any group. Only in group E, maximal tidal volume increased by 6.3% (p = 0.01). The ARDS volume of 1000 mL with the diameter of 2.5 cm applied in moderate-intensity swimming training constituted too weak a stimulus to develop respiratory muscles and lung function measured in the spirometry test.
Knowledge and Practices Related to Salt Intake among Saudi Adults
Authors: Hanbazaza Mahitab A. , Mumena Walaa A.
Published: August 2020

In Saudi Arabia, data regarding salt-related knowledge and practices are still lacking. This cross-sectional study aimed to investigate salt-related knowledge and practices and associated factors in Saudi adults. Data on the following variables were collected from 467 participants living in Madinah or Jeddah via face-to-face interviews: demographics, anthropometrics (height and weight), blood pressure (assessed using a digital sphygmomanometer), salt-related knowledge, and practices related to salt intake. Salt-related knowledge and practices were limited among the study participants; however, they were not correlated (rs = 0.10). Multiple linear regression analysis revealed that salt-related practices were negatively associated with sodium intake and positively associated with body mass index (BMI) (p < 0.001 and p = 0.001, respectively), whereas salt-related knowledge was not associated with sodium intake, blood pressure, or BMI. Salt-related knowledge is limited and not linked to practices related to salt intake in Saudi adults. Interventions are needed to increase the accessibility of low-sodium food options and improve practices limiting sodium intake to prevent the occurrence of salt-related diseases among adults in Saudi Arabia.
Effects of Carrying Police Equipment on Spatiotemporal and Kinetic Gait Parameters in First Year Police Officers
Authors: Kasović Mario , Štefan Lovro , Borovec Krunoslav , Zvonař Martin , Cacek Jan
Published: August 2020

The main purpose of the study was to explore the effects of carrying police equipment on spatiotemporal and kinetic gait parameters. Two-hundred and seventy-five healthy men and women attending police academy (32% women) were randomly recruited. Gait analysis without and with a police equipment load (≈3.5 kg) was analyzed using the Zebris pressure platform. Differences and effect sizes were calculated using a Student t-test and Wilcoxon test for dependent samples and Cohen’s D statistics. In both men and women, carrying police equipment significantly increased the foot rotation (effect size 0.13–0.25), step width (0.13–0.33), step time (0.25), stride time (0.13–0.25) and peak plantar pressure beneath the forefoot (0.16–0.30), midfoot (0.15–0.32) and hindfoot (0.13–0.25) region of the foot. Significant reductions in the step length (0.12–0.25), stride length (0.14–0.23), cadence (0.15–0.28) and walking speed (0.20–0.22) were observed in both sexes. Although significant, the effect sizes were mostly trivial in men and small in women. Our study shows significant changes in the spatiotemporal and kinetic gait parameters when carrying police equipment for both men and women. Although the effect sizes are trivial to small, carrying police equipment of ≈3.5 kg may have a negative impact on gait characteristics in first-year police officers.