bluuebunny/crossref_metadata_2025 huggingface dataset:
Open-Surface River Extraction Based on Sentinel-2 MSI Imagery and DEM Data: Case Study of the Upper Yellow River
Authors: Li Dan , Wu Baosheng , Chen Bowei , Qin Chao , Wang Yanjun , Zhang Yi , Xue Yuan
Published: August 2020

Water is essential for the survival of plants, animals, and human beings. It is imperative to effectively manage and protect aquatic resources to sustain life on Earth. Small tributaries are an important water resource originating in mountain areas, they play an important role in river network evolution and water transmission and distribution. Snow and cloud cover cast shadows leading to misclassification in optical remote sensing images, especially in high-mountain regions. In this study, we effectively extract small and open-surface river information in the Upper Yellow River by fusing Sentinel-2 with 10 m resolution optical imagery corresponding to average discharge of the summer flood season and the 90 m digital elevation model (DEM) data. To effectively minimize the impact of the underlying surface, the study area was divided into five sub-regions according to underlying surface, terrain, and altitude features. We minimize the effects of cloud, snow, and shadow cover on the extracted river surface via a modified normalized difference water index (MNDWI), revised normalized difference water index (RNDWI), automated water extraction index (AWEI), and Otsu threshold method. Water index calculations and water element extractions are operated on the Google Earth Engine (GEE) platform. The river network vectors derived from the DEM data are used as constraints to minimize background noise in the extraction results. The accuracy of extracted river widths is assessed using different statistical indicators such as the R-square (R2) value, root mean square error (RMSE), mean bias error (MBE). The results show the integrity of the extracted small river surface by the RNDWI index is optimal. Overall, the statistical evaluation indicates the accuracy of the extracted river widths is satisfactory. The effective river width that can be accurately extracted based on satellite images is three times the image resolution. Sentinel-2 MSI images with a spatial resolution of 10 m are used to find that the rivers over 30 m wide can be connectedly, accurately extracted with the proposed method. Results of this work can enrich the river width database in the northeast Tibetan Plateau and its boundary region. The river width information may provide a foundation for studying the spatiotemporal changes in channel geometry of river systems in high-mountain regions. They can also supplement the necessary characteristic river widths information for the river network in unmanned mountain areas, which is of great significance for the accurate simulation of the runoff process in the hydrological model.
A Framework for Multi-Agent UAV Exploration and Target-Finding in GPS-Denied and Partially Observable Environments
Authors: Walker Ory , Vanegas Fernando , Gonzalez Felipe
Published: August 2020

The problem of multi-agent remote sensing for the purposes of finding survivors or surveying points of interest in GPS-denied and partially observable environments remains a challenge. This paper presents a framework for multi-agent target-finding using a combination of online POMDP based planning and Deep Reinforcement Learning based control. The framework is implemented considering planning and control as two separate problems. The planning problem is defined as a decentralised multi-agent graph search problem and is solved using a modern online POMDP solver. The control problem is defined as a local continuous-environment exploration problem and is solved using modern Deep Reinforcement Learning techniques. The proposed framework combines the solution to both of these problems and testing shows that it enables multiple agents to find a target within large, simulated test environments in the presence of unknown obstacles and obstructions. The proposed approach could also be extended or adapted to a number of time sensitive remote-sensing problems, from searching for multiple survivors during a disaster to surveying points of interest in a hazardous environment by adjusting the individual model definitions.
Recent Progress in Plasmonic Biosensing Schemes for Virus Detection
Authors: Mauriz Elba
Published: August 2020

The global burden of coronavirus disease 2019 (COVID-19) to public health and global economy has stressed the need for rapid and simple diagnostic methods. From this perspective, plasmonic-based biosensing can manage the threat of infectious diseases by providing timely virus monitoring. In recent years, many plasmonics’ platforms have embraced the challenge of offering on-site strategies to complement traditional diagnostic methods relying on the polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays (ELISA). This review compiled recent progress on the development of novel plasmonic sensing schemes for the effective control of virus-related diseases. A special focus was set on the utilization of plasmonic nanostructures in combination with other detection formats involving colorimetric, fluorescence, luminescence, or Raman scattering enhancement. The quantification of different viruses (e.g., hepatitis virus, influenza virus, norovirus, dengue virus, Ebola virus, Zika virus) with particular attention to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was reviewed from the perspective of the biomarker and the biological receptor immobilized on the sensor chip. Technological limitations including selectivity, stability, and monitoring in biological matrices were also reviewed for different plasmonic-sensing approaches.
Non-Uniformly Powered and Spaced Corporate Feeding Power Divider for High-Gain Beam with Low SLL in Millimeter-Wave Antenna Array
Authors: Uddin Md Nazim , Choi Sangjo
Published: August 2020

A corporate feeding antenna array with parasitic patches has been investigated previously for millimeter-wave applications due to its high gain and wide bandwidth. However, the parasitic patch integration in the uniformly powered and spaced patch antenna array led to a high sidelobe level (SLL). In this study, we designed a non-uniformly powered and spaced corporate feeding network to feed a 12-element parasitic patch-integrated microstrip antenna array for SLL reduction at 28 GHz in the millimeter-wave band. In the power divider, we arranged two one-to-six unequally feeding power dividers from the opposite side to feed 12 antenna elements with non-uniform excitation, and effectively controlled the spacing between antenna elements. The two opposite input ports from the power divider were fed 180° out-of-phase for good isolation between the adjacent antenna elements. To verify the SLL reduction effect from the non-uniform spacing in the array, we designed two non-uniformly powered patch antenna arrays with uniform and non-uniform spacing. In the measurement, the non-uniformly powered and spaced patch antenna array demonstrated a nearly 16.56 dBi boresight gain and −17.27 dB SLL, which is nearly 2 dB lower than the uniformly spaced counterpart. Finally, we expect that the non-uniformly powered and spaced high gain patch antenna array with a low SLL will be suitable for millimeter-wave communication applications.
Gait Activity Classification on Unbalanced Data from Inertial Sensors Using Shallow and Deep Learning
Authors: Lopez-Nava Irvin Hussein , Valentín-Coronado Luis M. , Garcia-Constantino Matias , Favela Jesus
Published: August 2020

Activity recognition is one of the most active areas of research in ubiquitous computing. In particular, gait activity recognition is useful to identify various risk factors in people’s health that are directly related to their physical activity. One of the issues in activity recognition, and gait in particular, is that often datasets are unbalanced (i.e., the distribution of classes is not uniform), and due to this disparity, the models tend to categorize into the class with more instances. In the present study, two methods for classifying gait activities using accelerometer and gyroscope data from a large-scale public dataset were evaluated and compared. The gait activities in this dataset are: (i) going down an incline, (ii) going up an incline, (iii) walking on level ground, (iv) going down stairs, and (v) going up stairs. The proposed methods are based on conventional (shallow) and deep learning techniques. In addition, data were evaluated from three data treatments: original unbalanced data, sampled data, and augmented data. The latter was based on the generation of synthetic data according to segmented gait data. The best results were obtained with classifiers built with augmented data, with F-measure results of 0.812 (σ = 0.078) for the shallow learning approach, and of 0.927 (σ = 0.033) for the deep learning approach. In addition, the data augmentation strategy proposed to deal with the unbalanced problem resulted in increased classification performance using both techniques.
Improved Defect Detection of Guided Wave Testing Using Split-Spectrum Processing
Authors: Pedram Seyed Kamran , Gan Tat-Hean , Ghafourian Mahdieh
Published: August 2020

Ultrasonic guided wave (UGW) testing is widely applied in numerous industry areas for the examination of pipelines where structural integrity is of concern. Guided wave testing is capable of inspecting long lengths of pipes from a single tool location using some arrays of transducers positioned around the pipe. Due to dispersive propagation and the multimodal behavior of UGW, the received signal is usually degraded and noisy, that reduce the inspection range and sensitivity to small defects. Therefore, signal interpretation and identifying small defects is a challenging task in such systems, particularly for buried/coated pipes, in that the attenuation rates are considerably higher compared with a bare pipe. In this work, a novel solution is proposed to address this issue by employing an advanced signal processing approach called “split-spectrum processing” (SSP) to minimize the level of background noise and enhance the signal quality. The SSP technique has already shown promising results in a limited trial for a bar pipe and, in this work, the proposed technique has been experimentally compared with the traditional approach for coated pipes. The results illustrate that the proposed technique significantly increases the signal-to-noise ratio and enhances the sensitivity to small defects that are hidden below the background noise.
WASN-Based Day–Night Characterization of Urban Anomalous Noise Events in Narrow and Wide Streets
Authors: Alías Francesc , Socoró Joan Claudi , Alsina-Pagès Rosa Ma
Published: August 2020

In addition to air pollution, environmental noise has become one of the major hazards for citizens, being Road Traffic Noise (RTN) as its main source in urban areas. Recently, low-cost Wireless Acoustic Sensor Networks (WASNs) have become an alternative to traditional strategic noise mapping in cities. In order to monitor RTN solely, WASN-based approaches should automatize the off-line removal of those events unrelated to regular road traffic (e.g., sirens, airplanes, trams, etc.). Within the LIFE DYNAMAP project, 15 urban Anomalous Noise Events (ANEs) were described through an expert-based recording campaign. However, that work only focused on the overall analysis of the events gathered during non-sequential diurnal periods. As a step forward to characterize the temporal and local particularities of urban ANEs in real acoustic environments, this work analyses their distribution between day (06:00–22:00) and night (22:00–06:00) in narrow (1 lane) and wide (more than 1 lane) streets. The study is developed on a manually-labelled 151-h acoustic database obtained from the 24-nodes WASN deployed across DYNAMAP’s Milan pilot area during a weekday and a weekend day. Results confirm the unbalanced nature of the problem (RTN represents 83.5% of the data), while identifying 26 ANE subcategories mainly derived from pedestrians, animals, transports and industry. Their presence depends more significantly on the time period than on the street type, as most events have been observed in the day-time during the weekday, despite being especially present in narrow streets. Moreover, although ANEs show quite similar median durations regardless of time and location in general terms, they usually present higher median signal-to-noise ratios at night, mainly on the weekend, which becomes especially relevant for the WASN-based computation of equivalent RTN levels.
An Acridine-Based Fluorescent Sensor for Monitoring ClO− in Water Samples and Zebrafish
Authors: Lee Su Chan , Park Soyoung , So Haeri , Lee Gyudong , Kim Ki-Tae , Kim Cheal
Published: August 2020

A novel acridine-based fluorescent chemosensor, BK ((E)-2-((acridine-9-ylimino)methyl)-N-benzhydrylhydrazine-1-carbothioamide), for monitoring ClO− was prepared. The sensor BK was synthesized by introducing a new synthetic route of making aldehyde group using formic hydrazide. Probe BK displayed notable fluorescence quenching in the presence of ClO− and showed a great selectivity over other guest analytes. The detection limit was calculated to be 7.65 μM. Additionally, BK was satisfactorily applied for sensing ClO− in water samples and zebrafish.
Dual Wavelength Differential Detection of Fiber Bragg Grating Sensors with a Pulsed DFB Laser
Authors: Ouellette François , Ou Zhonghua , Li Jianfeng
Published: August 2020

We show how dual wavelength differential detection can be used to measure fiber Bragg grating sensors using nanosecond pulses from a single DFB laser diode, by taking advantage of its dynamic chirp. This can be performed in two ways: by measuring the reflected power from two separate pulses driven by two different currents, or by taking two delayed digitized samples within a single pulse. A prototype instrument using fast digitizing and processing with an FPGA is used to characterize the chirp, from which the performance can be optimized for both measurement schemes.
A Novel Simulated Annealing Based Strategy for Balanced UAV Task Assignment and Path Planning
Authors: Huo Lisu , Zhu Jianghan , Wu Guohua , Li Zhimeng
Published: August 2020

The unmanned aerial vehicle (UAV) has drawn increasing attention in recent years, especially in executing tasks such as natural disaster rescue and detection, and battlefield cooperative operations. Task assignment and path planning for multiple UAVs in the above scenarios are essential for successful mission execution. But, effectively balancing tasks to better excavate the potential of UAVs remains a challenge, as well as efficiently generating feasible solutions from the current one in constrained explosive solution spaces with the increase in the scale of optimization problems. This paper proposes an efficient approach for task assignment and path planning with the objective of balancing the tasks among UAVs and achieving satisfactory temporal resolutions. To be specific, we add virtual nodes according to the number of UAVs to the original model of the vehicle routing problem (VRP), thus make it easier to form a solution suitable for heuristic algorithms. Besides, the concept of the universal distance matrix is proposed to transform the temporal constraints to spatial constraints and simplify the programming model. Then, a Swap-and-Judge Simulated Annealing (SJSA) algorithm is therefore proposed to improve the efficiency of generating feasible neighboring solutions. Extensive experimental and comparative studies on different scenarios demonstrate the efficiency of the proposed algorithm compared with the exact algorithm and meta-heuristic algorithms. The results also inspire us about the characteristics of a population-based algorithm in solving combinatorial discrete optimization problems.
Assessment of Upper Limb Movement Impairments after Stroke Using Wearable Inertial Sensing
Authors: Schwarz Anne , Bhagubai Miguel M. C. , Wolterink Gerjan , Held Jeremia P. O. , Luft Andreas R. , Veltink Peter H.
Published: August 2020

Precise and objective assessments of upper limb movement quality after strokes in functional task conditions are an important prerequisite to improve understanding of the pathophysiology of movement deficits and to prove the effectiveness of interventions. Herein, a wearable inertial sensing system was used to capture movements from the fingers to the trunk in 10 chronic stroke subjects when performing reach-to-grasp activities with the affected and non-affected upper limb. It was investigated whether the factors, tested arm, object weight, and target height, affect the expressions of range of motion in trunk compensation and flexion-extension of the elbow, wrist, and finger during object displacement. The relationship between these metrics and clinically measured impairment was explored. Nine subjects were included in the analysis, as one had to be excluded due to defective data. The tested arm and target height showed strong effects on all metrics, while an increased object weight showed effects on trunk compensation. High inter- and intrasubject variability was found in all metrics without clear relationships to clinical measures. Relating all metrics to each other resulted in significant negative correlations between trunk compensation and elbow flexion-extension in the affected arm. The findings support the clinical usability of sensor-based motion analysis.
ANN-Based Estimation of Low-Latitude Monthly Ocean Latent Heat Flux by Ensemble Satellite and Reanalysis Products
Authors: Chen Xiaowei , Yao Yunjun , Li Yufu , Zhang Yuhu , Jia Kun , Zhang Xiaotong , Shang Ke , Yang Junming , Bei Xiangyi , Guo Xiaozheng
Published: August 2020

Ocean latent heat flux (LHF) is an essential variable for air–sea interactions, which establishes the link between energy balance, water and carbon cycle. The low-latitude ocean is the main heat source of the global ocean and has a great influence on global climate change and energy transmission. Thus, an accuracy estimation of high-resolution ocean LHF over low-latitude area is vital to the understanding of energy and water cycle, and it remains a challenge. To reduce the uncertainties of individual LHF products over low-latitude areas, four machine learning (ML) methods (Artificial Neutral Network (ANN), Random forest (RF), Bayesian Ridge regression and Random Sample Consensus (RANSAC) regression) were applied to estimate low-latitude monthly ocean LHF by using two satellite products (JOFURO-3 and GSSTF-3) and two reanalysis products (MERRA-2 and ERA-I). We validated the estimated ocean LHF using 115 widely distributed buoy sites from three buoy site arrays (TAO, PIRATA and RAMA). The validation results demonstrate that the performance of LHF estimations derived from the ML methods (including ANN, RF, BR and RANSAC) were significantly better than individual LHF products, indicated by R2 increasing by 3.7–46.4%. Among them, the LHF estimation using the ANN method increased the R2 of the four-individual ocean LHF products (ranging from 0.56 to 0.79) to 0.88 and decreased the RMSE (ranging from 19.1 to 37.5) to 11 W m−2. Compared to three other ML methods (RF, BR and RANSAC), ANN method exhibited the best performance according to the validation results. The results of relative uncertainty analysis using the triangle cornered hat (TCH) method show that the ensemble LHF product using ML methods has lower relative uncertainty than individual LHF product in most area. The ANN was employed to implement the mapping of annual average ocean LHF over low-latitude at a spatial resolution of 0.25° during 2003–2007. The ocean LHF fusion products estimated from ANN methods were 10–30 W m−2 lower than those of the four original ocean products (MERRA-2, JOFURO-3, ERA-I and GSSTF-3) and were more similar to observations.
A Simple, Low Cost, Sensitive, and Portable Electrochemical Immunochromatography Sensing Device to Measure Estrone-3-Sulfate
Authors: Iwasaki Wataru , Kataoka Chiwa , Sawadaishi Kazuyuki , Suyama Keitaro , Morita Nobutomo , Miyazaki Masaya
Published: August 2020

In livestock production, point-of-care testing (POCT) technology that enables easy on-site analysis of sex hormones is desired to improve reproductive efficiency. In this context, low-molecular-weight endogenous steroids are particularly important for perinatal management. Therefore, we attempted to use a simple method that combines electrochemical techniques with immunochromatography to measure estrone-3-sulfate (E1S), one of the low-molecular-weight endogenous steroids that is an estrogen ester. The limit of detection (LOD) for E1S achieved by electrochemical immunochromatography was 570.5 ng/mL, which was one to two orders of magnitude lower than that of small molecule compounds analyzed by other POCT techniques (Primpray et al., Anal. Chim. Acta, 2019). In addition, it was indicated by a colorimetric analysis that the sensitivity of the electrochemical immunochromatographic technique could be enhanced by improving the method of application of the antibodies on the nitrocellulose membrane and the contact between the electrochemical detector and the nitrocellulose membrane.
Income Inequality and CO2 Emissions in Developing Countries: The Moderating Role of Financial Instability
Authors: Yang Bo , Ali Minhaj , Hashmi Shujahat Haider , Shabir Mohsin
Published: August 2020

This paper studies the effects of income inequality and financial instability on CO2 emissions in the presence of fossil fuel energy, economic development, industrialization, and trade openness. Moreover, the present study is the first to examine the moderating role of financial instability between income inequality and CO2 emissions. We utilized panel data of forty-seven developing countries for the period 1980–2016 by utilizing the stochastic impacts by regression on population, affluence, and technology (STIRPAT) model. The empirical outcomes in all models indicate that income inequality and industrialization significantly reduce environmental degradation, while fossil fuel, trade openness, and economic growth decrease the quality of the environment. However, financial instability (without interaction term) shows no significant link to environmental quality, whereas (with interaction term) it shows a significant negative effect on CO2 emissions. In addition, the result of the interaction variable reveals that an increase in inequality, ceteris paribus, in combination with the rise in financial instability, is expected to increase pollution. Furthermore, there exists a bidirectional causal association among income inequality, financial instability, fossil fuel, trade openness, industrialization, economic growth, and the interaction variable with CO2 emissions.
Bibliometric Review: Classroom Management in ADHD—Is There a Communication Gap Concerning Knowledge Between the Scientific Fields Psychiatry/Psychology and Education?
Authors: Dort Martina , Strelow Anna Enrica , French Blandine , Groom Madeleine , Luman Marjolein , Thorell Lisa B. , Biele Guido , Christiansen Hanna
Published: August 2020

Many students with ADHD experience educational attainment difficulties. Nevertheless, evidence-based classroom management strategies (CMS) are seldom used. This science–practitioner gap might be due to a lack of shared knowledge between the scientific fields of psychology/psychiatry and education. This review uses science mapping to explore the basis of the current stock of knowledge in each of the two scientific fields, compares current approaches, and examines whether implementation methods and related barriers are investigated topics. We conducted a systematic search of the literature to identify articles on CMS in ADHD. We then conducted co-citation analyses and bibliographic coupling analysis. The former revealed six clusters of psychology/psychiatry and five clusters of education. Bibliographic coupling analysis resulted in eight clusters, with literature from both fields. The majority of the research is conducted in the field of psychology/psychiatry; teachers’ perspectives are focused only in the field of education. The number of studies on implementation and potential barriers is small. There was thus relatively little communication between the sciences, but the scientific fields have seemed to converge recently. Connecting the scientific fields more and concentrating on implementation methods and barriers is strongly needed to close the science–practitioner gap.
Battery Manufacturing Resource Assessment to Minimise Component Production Environmental Impacts
Authors: Díaz-Ramírez Maryori C. , Ferreira Victor J. , García-Armingol Tatiana , López-Sabirón Ana M. , Ferreira Germán
Published: August 2020

A promising route to attain a reliable impact reduction of supply chain materials is based on considering circular economy approaches, such as material recycling strategies. This work aimed to evaluate potential benefits of recycling scenarios for steel, copper, aluminium and plastic materials to the battery manufacturing stage. Focused on this aim, the life cycle assessment (LCA) and the environmental externalities methodologies were applied to two battery study cases: lithium manganese oxide and vanadium redox flow (VRFB) batteries, based on a cradle-to-gate LCA approach. In general, the results provided an insight into the raw material handling route. Environmental impacts were diminished by more than 20% in almost all the indicators, due to the lower consumption of virgin materials related to the implemented recyclability route. Particularly, VRFB exhibited better recyclability ratio than the Li-ion battery. For the former, the key components were the periphery ones attaining around 70% of impact reduction by recycling steel. Components of the power subsystem were also relevant, reaching around 40% of environmental impact reduction by recycling plastic. The results also foresaw opportunities for membranes, key components of VRFB materials. Based on findings, recycling strategies may improve the total circularity performance and economic viability of the studied systems.
Identification of Roof Surfaces from LiDAR Cloud Points by GIS Tools: A Case Study of Lučenec, Slovakia
Authors: Gergelova Marcela Bindzarova , Labant Slavomir , Kuzevic Stefan , Kuzevicova Zofia , Pavolova Henrieta
Published: August 2020

The identification of roof surfaces is characterized by a sequence of several processing steps. The boundary detection of different types of roof is realized from light detection and ranging (LiDAR) cloud points and can confirm the real boundary of the roof. In the process of processing LiDAR data, shortcomings have been found regarding the inappropriate classification of points (class 6 “buildings”) concerning the roofs (the points of the building facade were marked as outliers and reclassified). In cases of insufficient point density, there is a problem with not being able to capture either the roof boundary or small roof objects, along with the possible occurrence of gaps inside the roof areas. This study proposes a processing procedure in a geographic information system (GIS) environment that advocates the identification of roof surfaces based on the LiDAR point cloud. We created the contours of a roof surface boundary with a simplified regular shape. From 824 roofs in the studied area, six different types of roof were selected, which this study presents in detail. The expected result of the study is the generation of segments inside the roof boundary. The study also includes the visualization of the outcomes of the spatial analyses of the identified roof surfaces, which forms the basis for determining the potential of solar systems with respect to green roofs for the development of smart city buildings.
Getting in the Flow Together: The Role of Social Presence, Perceived Enjoyment and Concentration on Sustainable Use Intention of Mobile Social Network Game
Authors: Wang Huimin , Lee Kyungtag
Published: August 2020

Mobile Social Network Games (MSNGs) are defined as a product that combines games and social network services (SNSs). Compared with games played individually, MSNGs offer additional enjoyment to users through competition or cooperation. Mobile phone games, which rely on SNS platforms, can develop a strong social presence for users. This study focuses on factors affecting the sustainable use intention of MSNGs. In our study, we chose social presence as our dependent variable and proved that the social presence perceived by players in MSNGs has a positive impact on the sustainable use intention through a series of mediator variables. Second, the game product itself can easily lead to player addiction; therefore, in this study, we use the flow theory—perceived enjoyment and concentration—as our mediator variables. The results showed that perceived enjoyment and concentration are important factors driving the attitude towards MSNGs and that attitude presents a significant positive effect on sustainable use intention. This study enhances the current understanding of sustainable use intention of MSNGs and provides practical implication for MSNG development strategies and the theoretical implication.
Identification of New Biocontrol Agent against Charcoal Rot Disease Caused by Macrophomina phaseolina in Soybean (Glycine max L.)
Authors: Yasmin Humaira , Naz Rabia , Nosheen Asia , Hassan Muhammad Nadeem , Ilyas Noshin , Sajjad Muhammad , Anjum Seemab , Gao Xiangkuo , Geng Zhide
Published: August 2020

Controlling agricultural pests using suitable biocontrol agents has been considered the best strategy for sustainable agriculture. Charcoal rot caused by a necrotrophic fungus Macrophomina phaseolina is responsible for a 30–50% annual reduction in soybean yield worldwide. Little is known about the role of Bacillus clausii in reducing charcoal rot disease severity in the soybean crop. In this study, we investigated plant growth promoting and antagonistic potential of Pseudomonas putida (MT604992) and Bacillus clausii (MT604989) against charcoal rot disease incidence in soybean. Among twenty bacteria isolated from soil and water samples of two different hot springs of Gilgit-Baltistan, Pakistan, 80% were siderophore positive; 65% were hydrogen cyanide (HCN) positive; 55%, 30%, and 75% were phosphate, potassium, and zinc solubilizers, respectively. Based on higher antagonistic activities and plant growth promoting traits five strains were selected for in vitro screening. Out of all tested strains, Pseudomonas putida and Bacillus clausii showed a significant increase in germination, growth, and disease suppression in soybean. These strains produced a pronounced increase in relative water content, photosynthetic pigments, membrane stability, proline, antioxidant enzymes status, phytohormones content (Salicylic acid, and Jasmonic acid), and disease suppression in comparison to control plants. Bacillus clausii mitigated the disease by 97% with a marked increase in the proline content (73% and 89%), superoxide dismutase (356% and 208%), peroxidase (439% and 138.6%), catalase (255.8% and 80.8%), and ascorbate peroxidase (228% and 90%) activities in shoots and roots, respectively. Infected plants showed an increase in salicylic acid and jasmonic acid content which was further increased with the application of the selected strains to increase resistance against pathogens. To our knowledge, this is the first study showing a rise in salicylic acid and jasmonic acid in Macrophomina phaseolina infected plants. These two strains are suggested as a cost-effective, eco-friendly, and sustainable alternative to chemical fungicides. However, there is a need to explore the field testing and molecular mechanisms leading to disease suppression by these strains.
The Impact of Behavioral Drivers on Adoption of Sustainable Agricultural Practices: The Case of Organic Farming in Turkey
Authors: Cakirli Akyüz Nuray , Theuvsen Ludwig
Published: August 2020

Adoption decisions represent a crucial topic in sustainable agriculture research, particularly in the organic agriculture sector; to understand farmers’ decision-making, research has to delve more deeply into the influences of farmers’ behavior. The aim of this study, therefore, is to determine the behavioral intentions of Turkish sultana raisin producers toward organic farming practices. The proposed model integrates basic elements of the Theory of Planned Behavior and the technology acceptance model, which is then tested with survey data gathered from conventional and organic farmers by applying structural equation modeling, a powerful multivariate statistical technique. The results reveal that organic agriculture is perceived as a useful low-cost innovation by conventional farmers. Relating the results to group comparisons indicates that members of the conventional group are significantly more likely to have a positive intention towards adopting organic farming practices. Our results suggest possible interventions that policymakers should implement not only to stimulate adoption intentions of conventional farmers, but also to sustain continuance of organic practices by current operators.
On Approximate Aesthetic Curves
Authors: Crăciun Ioana , Popa Dorian , Serdean Florina , Tudose Lucian
Published: August 2020

Symmetry plays an essential role for generating aesthetic forms. The curve is the basic element used by designers to obtain aesthetic forms. A curve with a linear logarithmic curvature graph gradient is called aesthetic curve. The aesthetic value of a curve increases when its gradient is close to a straight line. We introduce the notions of approximate aesthetic curves and approximate neutral curves and obtain estimations between the curvature of an approximate aesthetic/neutral curve and an aesthetic curve.
Mathematical Modeling for Prediction Dynamics of the Coronavirus Disease 2019 (COVID-19) Pandemic, Quarantine Control Measures
Authors: Prathumwan Din , Trachoo Kamonchat , Chaiya Inthira
Published: August 2020

A mathematical model for forecasting the transmission of the COVID-19 outbreak is proposed to investigate the effects of quarantined and hospitalized individuals. We analyze the proposed model by considering the existence and the positivity of the solution. Then, the basic reproduction number (R0)—the expected number of secondary cases produced by a single infection in a completely susceptible population—is computed by using the next-generation matrix to carry out the stability of disease-free equilibrium and endemic equilibrium. The results show that the disease-free equilibrium is locally asymptotically stable if R0<1, and the endemic equilibrium is locally asymptotically stable if R0>1. Numerical simulations of the proposed model are illustrated. The sensitivity of the model parameters is considered in order to control the spread by intervention strategies. Numerical results confirm that the model is suitable for the outbreak that occurred in Thailand.
Unexpected Toxicity of Green Tea Polyphenols in Combination with the Sambucus RIL Ebulin
Authors: Rojo M. Ángeles , Garrosa Manuel , Jiménez Pilar , Girbés Tomás , Garcia-Recio Verónica , Cordoba-Diaz Manuel , Cordoba-Diaz Damián
Published: August 2020

The safety of concentrated food complements intake is a major health concern. It has been well established that green tea polyphenols (GTPs) consumption promotes healthy effects. However, the ingestion of large amounts of GTPs is a matter of controversy due to reported adverse effects. We underwent a preliminary exploration of the effects of the oral administration of a standardized concentrated GTPs preparation on mice which suffered from reversible intestinal derangement promoted by sublethal amounts of the antiribosomal lectin ebulin f from dwarf elder (Sambucus ebulus L.). Neither independent oral administration of 30 mg/kg body weight Polyphenon 60 nor intraperitoneal administration of 2.5 mg/kg body weight ebulin f triggered lethal toxicity. In contrast, the simultaneous administration of these same doses of both Polyphenon 60 and ebulin f triggered an important and unexpected synergistic toxic action featured by the biphasic reduction of weight, which continued after eight days, reaching a reduction of 40%. Lethality appeared 2 days after the onset of the combined treatment and reached more than 50% after 10 days.
Spatiotemporal Regulation of Vibrio Exotoxins by HlyU and Other Transcriptional Regulators
Authors: Kim Byoung Sik
Published: August 2020

After invading a host, bacterial pathogens secrete diverse protein toxins to disrupt host defense systems. To ensure successful infection, however, pathogens must precisely regulate the expression of those exotoxins because uncontrolled toxin production squanders energy. Furthermore, inappropriate toxin secretion can trigger host immune responses that are detrimental to the invading pathogens. Therefore, bacterial pathogens use diverse transcriptional regulators to accurately regulate multiple exotoxin genes based on spatiotemporal conditions. This review covers three major exotoxins in pathogenic Vibrio species and their transcriptional regulation systems. When Vibrio encounters a host, genes encoding cytolysin/hemolysin, multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin, and secreted phospholipases are coordinately regulated by the transcriptional regulator HlyU. At the same time, however, they are distinctly controlled by a variety of other transcriptional regulators. How this coordinated but distinct regulation of exotoxins makes Vibrio species successful pathogens? In addition, anti-virulence strategies that target the coordinating master regulator HlyU and related future research directions are discussed.
Toll-Like Receptor 4 Signaling in the Ileum and Colon of Gnotobiotic Piglets Infected with Salmonella Typhimurium or Its Isogenic ∆rfa Mutants
Authors: Splichal Igor , Rychlik Ivan , Splichalova Iva , Karasova Daniela , Splichalova Alla
Published: August 2020

Salmonella Typhimurium is a Gram-negative bacterium that causes enterocolitis in humans and pigs. Lipopolysaccharide (LPS) is a component of the outer leaflet of Gram-negative bacteria that provokes endotoxin shock. LPS can be synthesized completely or incompletely and creates S (smooth) or R (rough) chemotypes. Toll-like receptors (TLR) 2, 4, and 9 initiate an inflammatory reaction to combat bacterial infections. We associated/challenged one-week-old gnotobiotic piglets with wild-type S. Typhimurium with S chemotype or its isogenic ∆rfa mutants with R chemotype LPS. The wild-type S. Typhimurium induced TLR2 and TLR4 mRNA expression but not TLR9 mRNA expression in the ileum and colon of one-week-old gnotobiotic piglets 24 h after challenge. The TLR2 and TLR4 stimulatory effects of the S. Typhimurium ∆rfa mutants were related to the completeness of their LPS chain. The transcription of IL-12/23 p40, IFN-γ, and IL-6 in the intestine and the intestinal and plasmatic levels of IL-12/23 p40 and IL-6 but not IFN-γ were related to the activation of TLR2 and TLR4 signaling pathways. The avirulent S. Typhimurium ∆rfa mutants are potentially useful for modulation of the TLR2 and TLR4 signaling pathways to protect the immunocompromised gnotobiotic piglets against subsequent infection with the virulent S. Typhimurium.
The Role of Epidermal Growth Factor Receptor Signaling Pathway during Bovine Herpesvirus 1 Productive Infection in Cell Culture
Authors: Qiu Wencai , Chang Long , He Yongming , Zhu Liqian
Published: August 2020

Accumulating studies have shown that the epidermal growth factor receptor (EGFR) signaling pathway plays an essential role in mediating cellular entry of numerous viruses. In this study, we report that bovine herpesvirus 1 (BoHV-1) productive infection in both the human lung carcinoma cell line A549 and bovine kidney (MDBK) cells leads to activation of EGFR, as demonstrated by the increased phosphorylation of EGFR at Tyr1068 (Y1068), which in turn plays important roles in virus infection. A time-of-addition assay supported that virus replication at post-entry stages was affected by the EGFR specific inhibitor Gefitinib. Interestingly, both phospholipase C-γ1 (PLC-γ1) and Akt, canonical downstream effectors of EGFR, were activated following virus infection in A549 cells, while Gefitinib could inhibit the activation of PLC-γ1 but not Akt. In addition, virus titers in A549 cells was inhibited by chemical inhibition of PLC-γ1, but not by the inhibition of Akt. However, the Akt specific inhibitor Ly294002 could significantly reduce the virus titer in MDBK cells. Taken together, our data suggest that PLC-γ1 is stimulated in part through EGFR for efficient replication in A549 cells, whereas Akt can be stimulated by virus infection independent of EGFR, and is not essential for virus productive infection, indicating that Akt modulates BoHV-1 replication in a cell type-dependent manner. This study provides novel insights on how BoHV-1 infection activates EGFR signaling transduction to facilitate virus replication.
A Simple and Cost-Effective DNA Preparation Method Suitable for High-Throughput PCR Quantification of Hepatitis B Virus Genomes
Authors: Jo Eunji , Yang Jaewon , Koenig Alexander , Yoon Seung , Windisch Marc
Published: August 2020

Hepatitis B virus (HBV) is a para-retrovirus that reverse transcribes its pregenomic RNA into relaxed circular DNA inside viral nucleocapsids. The number of HBV genomes produced in vitro is typically quantified using commercial silica-membrane-based nucleic acid purification kits to isolate total DNA followed by HBV-specific quantitative PCR (qPCR). However, despite the convenience of commercial kits, this procedure is costly and time-consuming due to multiple centrifugation steps, which produce unnecessary waste. Here, we report a rapid, cost-effective, and environmentally friendly total DNA preparation method. The assay is based on the simple incubation of detergent and proteinase K with cells or cell-free supernatants to permeabilize cells and disrupt viral particles. After heat inactivation and subsequent centrifugation to clear the lysates, DNA samples are directly subjected to qPCR to quantify HBV genomes. As a proof of concept, the assay was developed in 12-well plates to assess intra- and extracellular HBV genome equivalents (GEqs) of stably viral-replicating cell lines (e.g., HepAD38) and HBV-infected HepG2-NTCP cells, both treated with lamivudine (LMV), an HBV replication inhibitor. Viral DNA was also prepared from the serum of patients chronically infected with HBV. To validate the assay, a representative commercial DNA isolation kit was used side-by-side to isolate intra- and extracellular HBV DNA. Both methods yielded comparable amounts of HBV GEqs with comparable LMV 50% efficient concentration (EC50) values. The assay was subsequently adapted to 96- and 384-well microtiter plates using HepAD38 cells. The EC50 values were comparable to those obtained in 12-well plates. In addition, the calculated coefficient of variation, Z’ values, and assay window demonstrated high reproducibility and quality. We devised a novel, robust, reproducible, high-throughput microtiter plate DNA preparation method suitable for quantifying HBV GEqs by qPCR analysis. This strategy enables rapid and convenient quantitative analysis of multiple viral DNA samples in parallel to investigate intracellular HBV replication and the secretion of DNA-containing viral particles.
Kinetics of Anti-Hepatitis B Surface Antigen Titers in Nurse Students after a Two-Year Follow-Up
Authors: Verso Maria Gabriella , Costantino Claudio , Marrella Alessandro , Immordino Palmira , Vitale Francesco , Amodio Emanuele
Published: August 2020

Infection caused by hepatitis B virus (HBV) can be prevented through a safe and effective vaccine. This study analysed the kinetics of serum antibodies against hepatitis B surface antigen (HBsAg) (anti-HBs) titers in relation to previous vaccine boosters in Italian nursing students who were followed up for two years. Serum anti-HBs titers were evaluated at the first visit, after vaccine booster (if required) and at visit after two years. Overall, 483 students (mean age = 21.7 years; SD = 3.7) with median anti-HBs IgG titer of 6 mUI/mL (interquartile range (IQR) = 0–34) were enrolled. A total of 254 (52.5%) students with a titer lower than 10 mIU/mL were offered an anti-HBV booster at the first visit. Among these students, an exponential relation between anti-HBs IgG titer, one month after HBV booster and anti-HBs IgG titer two years later was found (y = 3.32 exp (0.0045x); R2 = 0.48; p < 0.001). Students with anti-HBV titer higher than 10 mIU/mL (N = 229) were followed up, and anti-HBs IgG titers at follow-up visit linearly correlated with anti-HBV baseline titers (y = 0.86x + 26.2; R2 = 0.67; p < 0.001). A decrease in anti-HBs titers can be expected a few years after the anti-HBV booster dose. This reduction is more pronounced than that observed in students not administered the booster dose and is exponential with respect to basal titers assessed after the booster dose.
A Scalable Topical Vectored Vaccine Candidate against SARS-CoV-2
Authors: Rohaim Mohammed A. , Munir Muhammad
Published: August 2020

The severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) caused an ongoing unprecedented global public health crises of coronavirus disease in 2019 (CoVID-19). The precipitously increased death rates, its impact on livelihood and trembling economies warrant the urgent development of a SARS-CoV-2 vaccine which would be safe, efficacious and scalable. Owing to unavailability of the vaccine, we propose a de novo synthesized avian orthoavulavirus 1 (AOaV-1)-based topical respiratory vaccine candidate against CoVID-19. Avirulent strain of AOaV-1 was engineered to express full length spike (S) glycoprotein which is highly neutralizing and a major protective antigen of the SARS-CoV-2. Broad-scale in vitro characterization of a recombinant vaccine candidate demonstrated efficient co-expression of the hemagglutinin-neuraminidase (HN) of AOaV-1 and S protein of SARS-CoV-2, and comparable replication kinetics were observed in a cell culture model. The recombinant vaccine candidate virus actively replicated and spread within cells independently of exogenous trypsin. Interestingly, incorporation of S protein of SARS-CoV-2 into the recombinant AOaV-1 particles attributed the sensitivity to anti-SARS-CoV-2 antiserum and more prominently to anti-AOaV-1 antiserum. Finally, our results demonstrated that the recombinant vaccine vector stably expressed S protein after multiple propagations in chicken embryonated eggs, and this expression did not significantly impact the in vitro growth characteristics of the recombinant. Taken together, the presented respiratory vaccine candidate is highly attenuated in primates per se, safe and lacking pre-existing immunity in human, and carries the potential for accelerated vaccine development against CoVID-19 for clinical studies.
Impacts of Data Quantity and Quality on Model Calibration: Implications for Model Parameterization in Data-Scarce Catchments
Authors: Huang Yingchun , Bardossy Andras
Published: August 2020

The application of hydrological models in data-scarce catchments is usually limited by the amount of available data. It is of great significance to investigate the impacts of data quantity and quality on model calibration—as well as to further improve the understanding of the effective estimation of robust model parameters. How to make adequate utilization of external information to identify model parameters of data-scarce catchments is also worthy of further exploration. HBV (Hydrologiska Byråns Vattenbalansavdelning) models was used to simulate streamflow at 15 catchments using input data of different lengths. The transferability of all calibrated model parameters was evaluated for two validation periods. A simultaneous calibration approach was proposed for data-scarce catchment by using data from the catchment with minimal spatial proximity. The results indicate that the transferability of model parameters increases with the increase of data used for calibration. The sensitivity of data length in calibration varies between the study catchments, while flood events show the key impacts on surface runoff parameters. In general, ten-year data are relatively sufficient to obtain robust parameters. For data-scarce catchments, simultaneous calibration with neighboring catchment may yield more reliable parameters than only using the limited data.