bluuebunny/crossref_metadata_2025 huggingface dataset:
Reference and Limit Governors for Limit Protection of Turbofan Engines
Authors: Xu Wenhao , Pan Muxuan , Qin Jiakun , Huang Jinquan
Published: July 2019

This paper proposes a novel architecture of limit protection including the references governors and limit governors and applies this architecture to limit protection in turbofan engines. References governors are designed as add-on schemes to a pre-stability engine control system that modifies reference commands to avoid constraints violation. Limit governors are proposed as an assistant part for references governors adjusting constraints to prevent references from stopping updates. The use of output admissible sets for a class of variable constraints is exploited to form invariant sets. Simulation results based on a turbofan engine model show that references governors with limit governors can effectively enforce the multiple constraints and provide enhanced engine thrust when steady violation occurs.
Appliance Classification by Power Signal Analysis Based on Multi-Feature Combination Multi-Layer LSTM
Authors: Kim Jin-Gyeom , Lee Bowon
Published: July 2019

The imbalance of power supply and demand is an important problem to solve in power industry and Non Intrusive Load Monitoring (NILM) is one of the representative technologies for power demand management. The most critical factor to the NILM is the performance of the classifier among the last steps of the overall NILM operation, and therefore improving the performance of the NILM classifier is an important issue. This paper proposes a new architecture based on the RNN to overcome the limitations of existing classification algorithms and to improve the performance of the NILM classifier. The proposed model, called Multi-Feature Combination Multi-Layer Long Short-Term Memory (MFC-ML-LSTM), adapts various feature extraction techniques that are commonly used for audio signal processing to power signals. It uses Multi-Feature Combination (MFC) for generating the modified input data for improving the classification performance and adopts Multi-Layer LSTM (ML-LSTM) network as the classification model for further improvements. Experimental results show that the proposed method achieves the accuracy and the F1-score for appliance classification with the ranges of 95–100% and 84–100% that are superior to the existing methods based on the Gated Recurrent Unit (GRU) or a single-layer LSTM.
Development of an Electrostatic Precipitator with Porous Carbon Electrodes to Collect Carbon Particles
Authors: Kawada Yoshihiro , Shimizu Hirotaka
Published: July 2019

Exhaust gases from internal combustion engines contain fine carbon particles. If a biofuel is used as the engine fuel for low-carbon emission, the exhaust gas still contains numerous carbon particles. For example, the ceramic filters currently used in automobiles with diesel engines trap these carbon particles, which are then burned during the filter regeneration process, thus releasing additional CO2. Electrostatic precipitators are generally suitable to achieve low particle concentrations and large treatment quantities. However, low-resistivity particles, such as carbon particles, cause re-entrainment phenomena in electrostatic precipitators. In this study, we develop an electrostatic precipitator to collect fine carbon particles. Woodceramics were used for the grounded electrode in the precipitator to collect carbon particles on the carbon electrode. Woodceramics are eco-friendly materials, made from sawdust. The electrical resistivity and surface roughness of the woodceramics are varied by the firing temperature in the production process. Woodceramics electrodes feature higher resistivity and roughness as compared to stainless-steel electrodes. We evaluated the influence of woodceramics electrodes on the electric field formed by electrostatic precipitators and calculated the corresponding charge distribution. Furthermore, the particle-collection efficiency of the developed system was evaluated using an experimental apparatus.
Free Convection of Hybrid Nanofluids in a C-Shaped Chamber under Variable Heat Flux and Magnetic Field: Simulation, Sensitivity Analysis, and Artificial Neural Networks
Authors: Bagheri Hamed , Behrang Mohammadali , Assareh Ehsanolah , Izadi Mohsen , Sheremet Mikhail A.
Published: July 2019

In the present investigation, the free convection energy transport was studied in a C-shaped tilted chamber with the inclination angle α that was filled with the MWCNT (MultiWall Carbon Nanotubes)-Fe3O4-H2O hybrid nanofluid and it is affected by the magnetic field and thermal flux. The control equations were numerically resolved by the finite element method (FEM). Then, using the artificial neural network (ANN) combined with the particles swarm optimization algorithm (PSO), the Nusselt number was predicted, followed by investigating the effect of parameters including the Rayleigh number (Ra), the Hartmann number (Ha), the nanoparticles concentration (φ), the inclination angle of the chamber (α), and the aspect ratio (AR) on the heat transfer rate. The results showed the high accuracy of the ANN optimized by the PSO algorithm in the prediction of the Nusselt number such that the mean squared error in the ANN model is 0.35, while in the ANN model, it was optimized using the PSO algorithm (ANN-PSO) is 0.22, suggesting the higher accuracy of the latter. It was also found that, among the studied parameters with an effect on the heat transfer rate, the Rayleigh number and aspect ratio have the greatest impact on the thermal transmission intensification. The obtained data also showed that a growth of the Hartmann number illustrates a reduction of the Nusselt number for high Rayleigh numbers and the heat transfer rate is almost constant for low Rayleigh number values.
The Effect of Fiber Orientation on Stochastic Reconstruction and Permeability of a Carbon Paper Gas Diffusion Layer
Authors: Gao Yuan , Jin Teng , Wu Xiaoyan , Zhang Tong
Published: July 2019

By analyzing the three-dimensional digital model of a real carbon paper gas diffusion layer (GDL) reconstructed by X-ray computed tomography (CT), it was found that fibers are not distributed at any angle but within a certain range. The fiber orientation can be represented by fiber pitch (i.e., the angle between a single fiber and the in-plane direction). The effect of fiber orientation on stochastic reconstruction and transport properties (permeability) was investigated in this paper to find which fiber pitch range can achieve a better GDL on fluid flow. First, the actual fiber pitch was measured by analyzing SGL-24BA images obtained by X-ray CT. Also, seven different ranges of fiber pitch were randomly chosen to reconstruct GDL. Then, the permeability of these digital models was calculated using the Lattice Bolzmann Method (LBM) and discussed to obtain the fiber pitch range of the optimal permeability. The results show that the mean fiber pitch of SGL-24BA is 2.40° and the individual values are all less than 6°, also, the permeability of the through-plane direction increases gradually as the range of fiber pitch increases, which can be used for the structural design of carbon paper GDL.
Optimal Scheduling of Distributed Energy Resources in Residential Building under the Demand Response Commitment Contract
Authors: Baek Keon , Ko Woong , Kim Jinho
Published: July 2019

This study proposes optimal day-ahead demand response (DR) participation strategies and distributed energy resource (DER) management in a residential building under an individual DR contract with a grid-system operator. First, this study introduces a DER management system in the residential building for participation to the day-ahead DR market. The distributed photovoltaic generation system (PV) and energy-storage system (ESS) are applied to reduce the electricity demand in the building and sell surplus energy on the grid. Among loads in the building, lighting (LTG) and heating, ventilation, and air conditioning (HVAC) loads are included in the DR program. In addition, it is assumed that a power management system of an electric vehicle (EV) charging station is integrated the DER management system. In order to describe stochastic behavior of EV owners, the uncertainty of EV is formulated based on their arrival and departure scenarios. For measuring the economic efficiency of the proposed model, we compare it with the DER self-consuming operation model without DR participation. The problem is solved using mixed integer linear programming to minimize the operating cost. The results in summer and winter are analyzed to evaluate the proposed algorithm’s validity. From these results, the proposed model can be confirmed as reducing operation cost compared to the reference model through optimal day-ahead DR capacity bidding and implementation.
Digital Commons and Citizen Coproduction in Smart Cities: Assessment of Brazilian Municipal E-Government Platforms
Authors: Rotta Maurício José Ribeiro , Sell Denilson , dos Santos Pacheco Roberto Carlos , Yigitcanlar Tan
Published: July 2019

Good governance practices through electronic government (eGov) platforms can be suitable instruments for strengthening the outcomes of smart city policies. While eGov is the application of information and communication technologies to public services, good governance defines how well public authorities manage public and social resources. Contemporary public management views, such as ‘new public service’, include citizen participation as a critical factor to sustainable government in smart cities. Public services, in the age of digital technology, need to not only be delivered through eGov platforms, but also need to be coproduced with the engagement of social players, e.g., citizens. In this sense, eGov platforms act as digital commons, and conceived as digital spaces, where citizens and public agents interact and collaborate. In this paper, we presented the Municipal eGov Platform Assessment Model (MEPA), which is a model specifically developed to evaluate eGov platforms regarding their potential to promote commons in smart cities. The study applied MEPA to 903 municipal websites across Brazil. The results revealed that the majority of investigated Brazilian eGov platforms have only a low level of digital commons maturity. This finding discloses less citizenship coproduction, and fewer opportunities for city smartness. As the MEPA model offers public authorities an instrument to depict weaknesses and strengths of municipal eGov platforms, its adoption provides an opportunity for authorities to plan and manage their platforms to act as promoters of digital commons and citizen coproduction.
Intelligent Classification Method for Grid-Monitoring Alarm Messages Based on Information Theory
Authors: Sun Guoqiang , Ding Xiaoliu , Wei Zhinong , Shen Peifeng , Zhao Yang , Huang Qiugen , Zhang Liang , Zang Haixiang
Published: July 2019

Alarm messages for grid monitoring are an important way to supervise the operation of power grids. Since the use of alarm messages is increasing exponentially due to the continuous expansion of the scale of power grids, a processing method for alarm messages based on statistics is proposed in this study. Entropy theory in information theory is introduced into the calculation of information value in power-grid alarming. By means of multiple entropy definitions, an evaluation index system for information value is constructed. Based on the analytic hierarchy process (AHP), various alarm-message entropies are used as indices to comprehensively assess the information value and level of each alarm message. Finally, an example is given to illustrate the effectiveness and practicality of the proposed method. This study provides a new idea for the intelligent classification of alarm messages.
Stochastic Evaluation of Landscapes Transformed by Renewable Energy Installations and Civil Works
Authors: Sargentis G.-Fivos , Dimitriadis Panayiotis , Ioannidis Romanos , Iliopoulou Theano , Koutsoyiannis Demetris
Published: July 2019

Renewable energy (RE) installations and civil works are beneficial in terms of sustainability, but a considerable amount of space in the landscape is required in order to harness this energy. In contemporary environmental theory the landscape is considered an environmental parameter and the transformation of the landscape by RE works has received increasing attention by the scientific community and affected societies. This research develops a novel computational stochastic tool the 2D Climacogram (2D-C) that allows the analysis and comparison of images of landscapes, both original and transformed by RE works. This is achieved by a variability characterization of the grayscale intensity of 2D images. A benchmark analysis is performed for art paintings in order to evaluate the properties of the 2D-C for image analysis, and the change in variability among images. Extensive applications are performed for landscapes transformed by RE works. Results show that the 2D-C is able to quantify the changes in variability of the image features, which may prove useful in the landscape impact assessment of large-scale engineering works.
Observer-Based Sliding Mode FTC for Multi-Area Interconnected Power Systems against Hybrid Energy Storage Faults
Authors: Yang Weilin , Yu Dong , Xu Dezhi , Zhang Yiwei
Published: July 2019

An observer-based sliding mode fault-tolerant controller is developed in this paper, which is applied to an interconnected power system with a hybrid energy storage system (HESS). The model of the interconnected power system with HESS is introduced first. An observer is then proposed to estimate the unknown but bounded load disturbances and the actuator fault. The sliding mode fault-tolerant controller is further designed based on the observer ensuring that the area control error of the interconnected power system asymptotically converges to zero. The stability and the convergence of the whole system are proven based on the Lyapunov stability theory. Finally, the effectiveness of the proposed fault-control scheme is demonstrated through simulations.
The Self-Degradation Mechanism of Polyvinyl Chloride-Modified Slag/Fly Ash Binder for Geothermal Wells
Authors: Tan Huijing , Zheng Xiuhua , Chen Long , Liu Kang , Zhu Wenxi , Xia Bairu
Published: July 2019

Polyvinyl chloride (PVC) releases hydrochloric acid (HCl) during its thermal degradation, and hydrochloric acid can react with hydration products of alkali-activated binders. According to this characteristic of PVC and the temperature change that occurs during the development of a geothermal well, the PVC was added into slag/fly ash binder to develop self-degradable materials. The thermal degradation properties of PVC, compressive strength, hydration products, and microstructure of binders at different stages were tested, in order to study the degradation mechanism of the material. It was found that 20% PVC reduced the compressive strength, decreasing the level of binder from 13.95% to 76.63%. The mechanism of PVC promoting the material degradation mainly includes the following: (1) the thermal degradation of PVC increases the number of multiple damage pores in the material, at a high temperature; (2) HCl generated by the PVC thermal degradation reacts with the binder gels, and breaks them into particles; and (3) HCl also reacts with other substances in the binder, including CaCO3 and NaOH in the pore solution.
Estimation of the Biot Number Using Genetic Algorithms: Application for the Drying Process
Authors: Górnicki Krzysztof , Winiczenko Radosław , Kaleta Agnieszka
Published: July 2019

The Biot number informs researchers about the controlling mechanisms employed for heat or mass transfer during the considered process. The mass transfer coefficients (and heat transfer coefficients) are usually determined experimentally based on direct measurements of mass (heat) fluxes or correlation equations. This paper presents the method of Biot number estimation. For estimation of the Biot number in the drying process, the multi-objective genetic algorithm (MOGA) was developed. The simultaneous minimization of mean absolute error (MAE) and root mean square error (RMSE) and the maximization of the coefficient of determination R2 between the drying model and experimental data were considered. The Biot number can be calculated from the following equations: Bi = 0.8193exp(−6.4951T−1) (and moisture diffusion coefficient from D/s2 = 0.00704exp(−2.54T−1)) (RMSE = 0.0672, MAE = 0.0535, R2 = 0.98) or Bi = 1/0.1746log(1193847T) (D/s2 = 0.0075exp(−6T−1)) (RMSE = 0.0757, MAE = 0.0604, R2 = 0.98). The conducted validation gave good results.
Reducing Computational Load for Mixed Integer Linear Programming: An Example for a District and an Island Energy System
Authors: Kannengießer Timo , Hoffmann Maximilian , Kotzur Leander , Stenzel Peter , Schuetz Fabian , Peters Klaus , Nykamp Stefan , Stolten Detlef , Robinius Martin
Published: July 2019

The complexity of Mixed-Integer Linear Programs (MILPs) increases with the number of nodes in energy system models. An increasing complexity constitutes a high computational load that can limit the scale of the energy system model. Hence, methods are sought to reduce this complexity. In this paper, we present a new 2-Level Approach to MILP energy system models that determines the system design through a combination of continuous and discrete decisions. On the first level, data reduction methods are used to determine the discrete design decisions in a simplified solution space. Those decisions are then fixed, and on the second level the full dataset is used to ex-tract the exact scaling of the chosen technologies. The performance of the new 2-Level Approach is evaluated for a case study of an urban energy system with six buildings and an island system based on a high share of renewable energy technologies. The results of the studies show a high accuracy with respect to the total annual costs, chosen system structure, installed capacities and peak load with the 2-Level Approach compared to the results of a single level optimization. The computational load is thereby reduced by more than one order of magnitude.
Optimal Investment Strategies for Solar Energy Based Systems
Authors: Song Yuchen , Hu Weihao , Xu Xiao , Huang Qi , Chen Gang , Han Xiaoyan , Chen Zhe
Published: July 2019

Solar energy, as an inexhaustible renewable energy, can be used to produce heat and electricity. It is of great importance to examine the strategy for investment on solar energy technology. In response to varying electricity price in the electricity market, the battery energy storage system (BESS) can be used to get price arbitrage. This paper proposes an optimal configuration model for a photovoltaic (PV) system, solar heating system, and BESS in order to obtain maximum profit for investors. The investment potential of these systems is compared and analyzed based on return on investment (ROI) index which is defined to evaluate economic profitability. A bi-level programming is adopted to optimize the operation strategy of batteries (inner layer), the size of PV system and solar heating system, and the size of batteries (outer layer) including their maximum discharge/charge power and capacity. Sequential quadratic programming (SQP) method and particle swarm optimization (PSO) are used as optimization methods. In the case study, five investment strategies are investigated in order to decide how to invest in PV modules, batteries, and solar thermal collectors. The results show that the BESS may be a preferable choice for the investors if the investment cost of BESS goes down a lot in the future. Investing in solar energy for both heat and power may be not reasonable because the ROI of this strategy is always higher than either investing in heat or in power. The optimal strategy may be changed with the fluctuation of heat and electricity prices.
Maximum Power Point Tracker Based on Fuzzy Adaptive Radial Basis Function Neural Network for PV-System
Authors: Bouarroudj Noureddine , Boukhetala Djamel , Feliu-Batlle Vicente , Boudjema Fares , Benlahbib Boualam , Batoun Bachir
Published: July 2019

In this article, a novel maximum power point tracking (MPPT) controller for a photovoltaic (PV) system is presented. The proposed MPPT controller was designed in order to extract the maximum of power from the PV-module and reduce the oscillations once the maximum power point (MPP) had been achieved. To reach this goal, a combination of fuzzy logic and an adaptive radial basis function neural network (RBF-NN) was used to drive a DC-DC Boost converter which was used to link the PV-module and a resistive load. First, a fuzzy logic system, whose single input was based on the incremental conductance (INC) method, was used for a variable voltage step size searching while reducing the oscillations around the MPP. Second, an RBF-NN controller was developed to keep the PV-module voltage at the optimal voltage generated from the first stage. To ensure a real MPPT in all cases (change of weather conditions and load variation) an adaptive law based on backpropagation algorithm with the gradient descent method was used to tune the weights of RBF-NN in order to minimize a mean-squared-error (MSE) criterion. Finally, through the simulation results, our proposed MPPT method outperforms the classical P and O and INC-adaptive RBF-NN in terms of efficiency.
Removing the Scaling Error Caused by Allometric Modelling in Forest Biomass Estimation at Large Scales
Authors: Zhou Carl , Zhou Xiaolu
Published: July 2019

To estimate the responses of forest ecosystems, most relationships in biological systems are described by allometric relationships, the parameters of which are determined based on field measurements. The use of existing observed data errors may occur during the scaling of fine-scale relationships to describe ecosystem properties at a larger ecosystem scale. Here, we analyzed the scaling error in the estimation of forest ecosystem biomass based on the measurement of plots (biomass or volume per hectare) using an improved allometric equation with a scaling error compensator. The efficiency of the compensator on reducing the scaling error was tested by simulating the forest stand populations using pseudo-observation. Our experiments indicate that, on average, approximately 94.8% of the scaling error can be reduced, and for a case study, an overestimation of 3.6% can be removed in practice from a large-scale estimation for the biomass of Pinus yunnanensis Franch.
Effect of Co-Inoculation with Pichia fermentans and Pediococcus acidilactici on Metabolite Produced During Fermentation and Volatile Composition of Coffee Beans
Authors: da Silva Vale Alexander , de Melo Pereira Gilberto Vinícius , de Carvalho Neto Dão Pedro , Rodrigues Cristine , Pagnoncelli Maria Giovana B. , Soccol Carlos Ricardo
Published: July 2019

Removal of the mucilage layer of coffee fruits by a fermentation process has became an interesting strategy to improve coffee quality, which is able to assist the formation of flavored molecules. In this study, four sets of inoculation protocols were evaluated using ripe and immature coffee fruits, respectively, including (i) pure culture fermentation with Pichia fermentans, (ii) pure culture fermentation with Pediococcus acidilactici, (ii) combined fermentation with P. fermentans and P. acidilactici, and (iv) spontaneous, non-inoculated control. The initial pulp sugar concentration of ripe coffee fruits (0.57 and 1.13 g/L glucose and fructose content, respectively) was significantly higher than immature coffee pulp (0.13 and 0.26 g/L glucose and fructose content, respectively). Combined inoculation with P. fermentans and P. acidilactici of ripe coffee beans increased pulp sugar consumption and production of metabolites (lactic acid, ethanol, and ethyl acetate), evidencing a positive synergic interaction between these two microbial groups. On the other hand, when immature coffee fruits were used, only pure culture inoculation with P. fermentans was able to improve metabolite formation during fermentation, while combined treatment showed no significant effect. Altogether, 30 volatile compounds were identified and semi-quantified with HS- solid phase microextraction (SPME)-gas chromatography coupled to mass spectrophotometry (GC/MS) in fermented coffee beans. In comparison with pure cultures and spontaneous process, combined treatment prominently enhanced the aroma complexity of ripe coffee beans, with a sharp increase in benzeneacetaldehyde, 2-heptanol, and benzylalcohol. Consistent with the monitoring of the fermentation process, only P. fermentans treatment was able to impact the volatile composition of immature coffee beans. The major impacted compounds were 2-hexanol, nonanal, and D-limonene. In summary, this study demonstrated the great potential of the combined use of yeast and lactic acid bacteria to improve fermentation efficiency and to positively influence the chemical composition of coffee beans. Further studies are still required to investigate the mechanisms of synergism between these two microbial groups during the fermentation process and influence the sensory properties of coffee products.
Maternal and Child Nutrition and Oral Health in Urban Vietnam
Authors: Huang Debbie , Sokal-Gutierrez Karen , Chung Kenny , Lin Wenting , Khanh Linh Ngo , Chung Raymond , Hoang Hung Trong , Ivey Susan L.
Published: July 2019

The global nutrition transition has contributed to child obesity and dental caries in developing countries, including Vietnam. Few studies have described the nutrition and oral health of mothers and children. This a descriptive study of the nutrition and oral health characteristics of a convenience sample of 571 children aged 2 to 5 years and their mothers from 5 urban preschools in Central and South Vietnam. The mothers completed a written survey, and the children received dental exams and weight/height measurements. High rates of bottle-feeding and the consumption of sweets were reported. One in 4 children were overweight/obese. Dental caries increased in prevalence and severity by age—at 5 years, 86.7% of children had tooth decay in an average of 8.5 teeth, and 70.9% experienced mouth pain. Most mothers and children suffered from untreated dental disease. Public health programs should focus on nutrition and oral health promotion, as well as dental treatment from pregnancy and birth onward.
Assessment of a Voluntary Non-Profit Health Insurance Scheme for Migrants along the Thai–Myanmar Border: A Case Study of the Migrant Fund in Thailand
Authors: Pudpong Nareerut , Durier Nicolas , Julchoo Sataporn , Sainam Pigunkaew , Kuttiparambil Beena , Suphanchaimat Rapeepong
Published: July 2019

Access to health care and financial protection for migrants can be promoted through diverse health insurance schemes, designed to suit migrants’ needs within a specific context. The Migrant Fund (M-Fund) is a voluntary, non-profit health insurance scheme operating along the Thai–Myanmar border in Thailand since 2017 and aims to protect the health of migrants uncovered by existing government insurance schemes. A qualitative evaluation was conducted between December 2018 and March 2019 to determine M-Fund’s operational impacts, provide recommendations for improvement, and draw suggestions about its role in protecting migrant health. In-depth interviews with 20 individuals and 5 groups were conducted in three categories: (1) International, national, and local partners; (2) M-Fund clients; and (3) M-Fund staff. Interview information was triangulated with findings from other informants, a document review, and researchers’ observations. Despite covering a small number of 9131 migrants, the M-Fund has contributed to improving access to care for migrants, raised awareness about migrant health protection, and reduced the financial burden for public hospitals. The M-Fund acts as a safety-net initiative for those left behind due to unclear government policy to protect the health of undocumented/illegal migrants. Despite clear merits, the issue of adverse selection to the scheme is a critical challenge. Evidence from this evaluation is useful to inform the future design of government insurance schemes for migrants.
Epidermal Growth Factor is Effective in the Treatment of Diabetic Foot Ulcers: Meta-Analysis and Systematic Review
Authors: Bui Thien Quoc , Bui Quoc Van Phu , Németh Dávid , Hegyi Péter , Szakács Zsolt , Rumbus Zoltán , Tóth Barbara , Emri Gabriella , Párniczky Andrea , Sarlós Patricia , Varga Orsolya
Published: July 2019

Diabetic foot ulcers (DFUs) are one the common complications of diabetes mellitus. Many trials were performed to evaluate the effect of recombinant human epidermal growth factor (rhEGF) in healing DFUs. This meta-analysis was performed to synthesize the evidence of rhEGF treatment in DFUs in comparison to placebo. Databases included for the search were PubMed, EMBASE, the Cochrane Library, Web of Science, EBSCOhost, ScienceDirect, and Scopus (up to January 2019). The outcome of interest was the complete healing rate of DFUs. We performed random effects meta-analysis stratified by the types of administration route (intralesional injection and topical apply) by calculating the odds ratios (OR) and 95% confidence interval (95% CI). A total of six studies involving 530 patients were eligible for analysis. The combined OR (intralesional injection and topical apply) was 4.005 (95% CI: (2.248; 7.135), p < 0.001). The ORs for intralesional injection and topical application were 3.599 (95% CI: (1.213; 10.677), p = 0.021) and 4.176 (95% CI: (2.112; 8.256), p < 0.001), respectively. Statistical heterogeneity might not be important in overall treatment (I2 = 15.17, p = 0.317) and both of the subgroups (I2: 24.56, p = 0.25 and I2: 33.26, p = 0.213, respectively). Our results support the use of rhEGF in the treatment of DFUs.
Contributions of Indoor and Outdoor Sources to Ozone in Residential Buildings in Nanjing
Authors: Huang Yu , Yang Zhe , Gao Zhi
Published: July 2019

Ozone has become one of the most serious air pollutants in China in recent years. Since people spend most of their time indoors, the ozone in the indoor environment could be a major factor affecting the occupants’ health. The indoor ozone in residential buildings mainly comes from two sources: outdoor atmosphere and indoor ozone produced by electrical devices. In this study, a typical residence in Nanjing was taken as an example to calculate and compare the contributions of indoor and outdoor sources to ozone in the building. A questionnaire survey about the type, the placement, and the frequency of use of the ozone emission devices was performed to provide the basis for the settings of indoor ozone sources. The multi-zone software CONTAM was used hourly to simulate the ozone concentration in summer and in winter with inner doors either closed or open, and it was noted whether there were ozone emission devices indoors or not. Source contribution was quantified and compared by three methods in this paper: (1) the average indoor/outdoor (I/O) ratio, (2) the I/O ratio frequency, and (3) the ratio of indoor ozone concentration without ozone sources to that with ozone sources. The results showed that the contribution of outdoor sources was much greater than that of indoor sources in summer, but in winter, the frequency of I/O > 1 could reach 55.8% of the total seasonal time, and the ratio of indoor ozone concentration without sources to that with sources could reach as high as 74.3%. This meant that the indoor concentration had the potential to exceed the outdoor. Furthermore, human respiratory exposure in different ages and genders was calculated. It was found that teenagers aged 10–18 years old and female adults had a higher respiratory exposure level.
Attending Informal Preschools and Daycare Centers Is a Risk Factor for Underweight, Stunting and Wasting in Children under the Age of Five Years in Underprivileged Communities in South Africa
Authors: Madiba Sphiwe , Chelule Paul Kiprono , Mokgatle Mathildah Mpata
Published: July 2019

The study objectives were to determine the nutritional status of children between the ages of 12–60 months and to establish the association between attending preschool and the prevalence of undernutrition. This was a cross-sectional survey conducted in health facilities in Tshwane district in South Africa, consisting of both a questionnaire and anthropometric measures of 1256 mothers and their children. Weight-for-age (WAZ), height-for age (HAZ) and BMI-for-age (BAZ) were calculated and bivariate and multivariable analysis was performed to establish association. The results showed that child-related factors, namely birthweight, age, gender, and attending preschool increased the risk of undernutrition. Children over the age of 24 months were likely to be stunted and underweight. Maternal education reduced the odds of underweight. Children who stayed at home had reduced odds of underweight and stunting. High birthweight reduced the odds of wasting and underweight. The risks for undernutrition are multifaceted, but children who attend preschool have an increased risk of undernutrition. The risk of undernutrition increased with age and coincided with the time of cessation of breast-feeding and attendance at daycare or preschool. The complementary role of quality childcare in preschools and daycare centers is vital in alleviating the problem of undernutrition in underprivileged communities.
Risk, Transformation and Adaptation: Ideas for Reframing Approaches to Disaster Risk Reduction
Authors: Paton Douglas , Buergelt Petra
Published: July 2019

Recognition of projected increases in exposure to large-scale hazard events over the coming decades has identified a need to develop how disaster risk reduction and recovery are conceptualized and enacted. This paper discusses some strategies for pursing this goal in both disaster recovery and preparedness settings. The approaches discussed include understanding how communities learn from their hazardous experiences and transform these lessons into beliefs, relationships and capabilities that build future adaptive capacity. The paper draws on examples of transformative learning that illustrate how people can make fundamental shifts in how they think about, prepare for and respond to environmental challenge and change. Regarding transformation in pre-event settings, the paper first discusses why the addition of transformative strategies to disaster risk reduction programs is required. These include a need for rethinking socio-environmental relationships, increasing risk acceptance in the context of evolving hazardscapes, and countering beliefs regarding not preparing. The paper then offers strategies for motivating transformation and consolidating the outcomes of transformation in pre-event disaster risk reduction (DRR) strategies. A preliminary model that could inform the development of research questions on the development of transformative outcomes and their consolidation in enduring adaptive processes is presented.
Absolute Income, Income Inequality and the Subjective Well-Being of Migrant Workers in China: Toward an Understanding of the Relationship and Its Psychological Mechanisms
Authors: Yu Kaizhi , Zhang Yun , Zou Hong , Wang Chenchen
Published: July 2019

No study has been conducted linking Chinese migrants’ subjective well-being (SWB) with urban inequality. This paper presents the effects of income and inequality on their SWB using a total of 128,000 answers to a survey question about “happiness”. We find evidence for a satiation point above which higher income is no longer associated with greater well-being. Income inequality is detrimental to well-being. Migrants report lower SWB levels where income inequality is higher, even after controlling for personal income, a large set of individual characteristics, and province dummies. We also find striking differences across socio-economic and geographic groups. The positive effect of income is more pronounced for rural and western migrants, and is shown to be significantly correlated with the poor’s SWB but not for the well-being of more affluent respondents. Interestingly, high-income earners are more hurt by income inequality than low-income respondents. Moreover, compared with migrants in other regions, those in less developed Western China are found to be more averse to income inequality. Our results are quite robust to different specifications. We provide novel explanations for these findings by delving into psychological channels, including egalitarian preferences, social comparison concerns, expectations, perceived fairness concerns and perceived social mobility.
Changes in Income after an Industrial Accident According to Industry and Return-to-Work Status
Authors: Bae Suk Won , Oh Sarah Soyeon , Park Wha Me , Roh Jaehoon , Won Jong-Uk
Published: July 2019

Objective: To investigate changes in the incomes of workers, particularly those in the construction sector, who experienced industrial accidents according to their status of return to work. Methods: We used data from the fifth Panel Study of Workers’ Compensation Insurance. A repeated measures ANOVA was used to compare annual differential incomes before and after the industrial accident, and a linear mixed model was used to investigate the changes in income from before to after the industrial accident according to the industry and return-to-work status. Results: A comparison of the industrial categories revealed that construction industry workers exhibited the greatest incomes before the accident and the greatest decrease in income after the industrial accident. Regression analysis for assessing changes in income after the industrial accident showed that a comparison by industry revealed a significantly greater reduction in income in the construction than service industry. A comparison by work status revealed significantly greater decreases in income in the reemployment and non-return to work groups than among those who returned to their original work. Conclusions: The economic statuses of the victims of industrial accidents decreased relative to the pre-accident statuses in all industries. The ability to return to original work is important for preserving the accident victim’s economic status.
Determination of Polycyclic Aromatic Hydrocarbons in Sludge from Water and Wastewater Treatment Plants by GC-MS
Authors: Chen Chih-Feng , Ju Yun-Ru , Lim Yee Cheng , Hsieh Shu-Ling , Tsai Mei-Ling , Sun Pei-Pei , Katiyar Ravi , Chen Chiu-Wen , Dong Cheng-Di
Published: July 2019

The qualitative and quantitative analysis of 16 polycyclic aromatic hydrocarbons (PAHs) in sludge samples from drinking water treatment plants (DWTP) and wastewater treatment plants (WWTP) were established using gas chromatography–mass spectrometry (GC-MS). The method was suitable to quantify PAHs in the sludge of DWTP and WWTP and it was confirmed by the relevant quality assurance/quality control (QA/QC) procedures. The recovery of individual PAHs in the spiked samples ranged from 74.3% to 108.7%. Detection limits of the analytical procedure were 0.0010–0.0046 mg/kg dw for individual PAHs. This method was used to determine the concentration of PAHs in the selected two DWTP and four WWTP sludge samples. The results showed that the total PAHs (∑PAHs) were in low levels which ranged from 0.0668 to 0.1357 mg/kg dw, and 0.5342–1.0666 mg/kg dw for DWTP and WWTP respectively. The 3- & 4-ring PAHs were predominant in DWTP sludge, ranging from 77.4% to 82.7%; the 4-ring PAHs were predominant in WWTP sludge, ranging from 40.7% to 47.6%. The PAHs of DWTP sludge are mainly composed of 3-ring phenanthrene and anthracene and 4-ring pyrene, and chrysene. The PAHs of WWTP sludge are dominated by 4-ring fluoranthene, pyrene, and chrysene. The detected PAHs concentration should be undoubtedly considered for agriculture in sludge applications based on the limits of the EU regulations. The results of this study can be used for regular monitoring to establish a reference for sludge management and application to agriculture.
An Inexact Optimization Model for Crop Area Under Multiple Uncertainties
Authors: Ren Chongfeng , Zhang Hongbo
Published: July 2019

This paper developed a type-2 fuzzy interval chance constrained programming model for optimizing a crop area, which integrated chance constrained programming and type-2 fuzzy interval programming. The developed model was then applied to a case study in Wuwei City, Gansu Province, China, and the maximization of economic benefit was selected as the planning objective. Furthermore, different water-saving irrigation modes were considered as the development mode. A series of optimal irrigation water and planting structure schemes were obtained under different violation probabilities in each water-saving scenario. The obtained results could be helpful to make decisions on the planting structure and the optimal use of irrigation water and land resources under multiple uncertainties.
A Dual GLP-1/GIP Receptor Agonist Does Not Antagonize Glucagon at Its Receptor but May Act as a Biased Agonist at the GLP-1 Receptor
Authors: Al-Zamel Noura , Al-Sabah Suleiman , Luqmani Yunus , Adi Lobna , Chacko Siby , Schneider Tom Dario , Krasel Cornelius
Published: July 2019

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are important regulators of metabolism, making their receptors (GLP-1R and GIPR) attractive targets in the treatment of type 2 diabetes mellitus (T2DM). GLP-1R agonists are used clinically to treat T2DM but the use of GIPR agonists remains controversial. Recent studies suggest that simultaneous activation of GLP-1R and GIPR with a single peptide provides superior glycemic control with fewer adverse effects than activation of GLP-1R alone. We investigated the signaling properties of a recently reported dual-incretin receptor agonist (P18). GLP-1R, GIPR, and the closely related glucagon receptor (GCGR) were expressed in HEK-293 cells. Activation of adenylate cyclase via Gαs was monitored using a luciferase-linked reporter gene (CRE-Luc) assay. Arrestin recruitment was monitored using a bioluminescence resonance energy transfer (BRET) assay. GLP-1, GIP, and glucagon displayed exquisite selectivity for their receptors in the CRE-Luc assay. P18 activated GLP-1R with similar potency to GLP-1 and GIPR with higher potency than GIP. Interestingly, P18 was less effective than GLP-1 at recruiting arrestin to GLP-1R and was inactive at GCGR. These data suggest that P18 can act as both a dual-incretin receptor agonist, and as a G protein-biased agonist at GLP-1R.
The Effect of Uncoated SPIONs on hiPSC-Differentiated Endothelial Cells
Authors: Salingova Barbara , Simara Pavel , Matula Pavel , Zajickova Lenka , Synek Petr , Jasek Ondrej , Veverkova Lenka , Sedlackova Miroslava , Nichtova Zuzana , Koutna Irena
Published: July 2019

Background: Endothelial progenitor cells (EPCs) were indicated in vascular repair, angiogenesis of ischemic organs, and inhibition of formation of initial hyperplasia. Differentiation of endothelial cells (ECs) from human induced pluripotent stem cells (hiPSC)-derived endothelial cells (hiPSC-ECs) provides an unlimited supply for clinical application. Furthermore, magnetic cell labelling offers an effective way of targeting and visualization of hiPSC-ECs and is the next step towards in vivo studies. Methods: ECs were differentiated from hiPSCs and labelled with uncoated superparamagnetic iron-oxide nanoparticles (uSPIONs). uSPION uptake was compared between hiPSC-ECs and mature ECs isolated from patients by software analysis of microscopy pictures after Prussian blue cell staining. The acute and long-term cytotoxic effects of uSPIONs were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay) and Annexin assay. Results: We showed, for the first time, uptake of uncoated SPIONs (uSPIONs) by hiPSC-ECs. In comparison with mature ECs of identical genetic background hiPSC-ECs showed lower uSPION uptake. However, all the studied endothelial cells were effectively labelled and showed magnetic properties even with low labelling concentration of uSPIONs. uSPIONs prepared by microwave plasma synthesis did not show any cytotoxicity nor impair endothelial properties. Conclusion: We show that hiPSC-ECs labelling with low concentration of uSPIONs is feasible and does not show any toxic effects in vitro, which is an important step towards animal studies.
Annona atemoya Leaf Extract Improves Scopolamine-Induced Memory Impairment by Preventing Hippocampal Cholinergic Dysfunction and Neuronal Cell Death
Authors: Sohn Eunjin , Lim Hye-Sun , Kim Yu Jin , Kim Bu-Yeo , Jeong Soo-Jin
Published: July 2019

We explored the preventative effect of Annona atemoya leaf (AAL) extract on memory impairment in a scopolamine (SCO)-induced cognitive deficit mouse model. Fifty-eight mice were randomly divided into six groups and orally treated with AAL extract at (50, 100, or 200 mg/kg) or tacrine (TAC) for 21 days. Memory deficits were induced by a single injection of 1 mg/kg SCO (i.p.) and memory improvement was evaluated by using behavioral tests such as the passive avoidance task and Y-maze test. The levels of cholinergic functions, neuronal cell death, reactive oxygen species, and protein expression related to hippocampal neurogenesis were examined by immunohistochemical staining and western blotting. The administration of AAL extract improved memory impairment according to increased spontaneous alternation in the Y-maze and step-through latency in passive avoidance test. AAL extract treatment increased the acetylcholine content, choline acetyltransferase, and acetylcholinesterase activity in the hippocampus of SCO-stimulated mice. In addition, AAL extract attenuated oxidative stress-induced neuronal cell death of hippocampal tissue. In terms of the regulatory mechanisms, AAL extract treatment reversed the SCO-induced decreases in the expression of Akt, phosphorylation of cAMP response element binding protein, and brain-derived neurotrophic factor. Our findings demonstrate that AAL extract has the ability to alleviate memory impairment through preventative effect on cholinergic system dysfunction and oxidative stress-related neuronal cell death in a SCO-induced memory deficit animal model. Overall, AAL may be a promising plant resource for the managing memory dysfunction due to neurodegenerative diseases, such as Alzheimer’s disease (AD).
Transcriptome Analysis Did Not Show Endogenous Stem Cell Characteristics in Murine Lgr5+ Retinal Cells
Authors: Trepp Carolyn , Quintela Pousa Ana Maria , Enzmann Volker
Published: July 2019

Lgr5, an intestinal adult stem cell marker, was recently also found in neuronal tissues. We investigated whether retinal Lgr5+ cells express properties of neural stem cells (NSC) and/or of differentiated interneurons during retinal development. RNA was isolated from Lgr5+ and Lgr5− populations from postnatal day 5 (PN5) and adult retinas of Lgr5EGFP-Ires-CreERT2 knock-in mice sorted by fluorescence-activated cell sorting (FACS). Transcriptome analyses were performed on two RNA samples of each developmental stage (PN5 and adult). The online platform PANTHER (Protein ANalysis THrough Evolutionary Relationships) was used to determine overrepresented gene ontology (GO) terms of biological processes within the set of differentially expressed genes. The detailed evaluation included gene expression in regard to stem cell maintenance/proliferation, cell cycle, and Wnt signaling but also markers of differentiated retinal neurons. None of the enriched GO terms of upregulated genes of Lgr5+ cells showed a positive association to NSC. On the contrary, NSC maintenance and proliferation rather prevail in the Lgr5− cell population. Furthermore, results suggesting that Wnt signaling is not active in the Lgr5+ population. Therefore, our transcriptome analysis of Lgr5+ retinal cells suggest that these cells are differentiated neurons, specifically glycinergic amacrine cells.