bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing and Benchmarking Learning Outcomes of Robotics-Enabled STEM Education
Authors: Rahman S. M. Mizanoor
Published: February 2021

Experienced middle school mathematics and science teachers were recruited for a pilot study. The teachers separately responded to a survey related to determining expected learning outcomes based on their traditional teaching, classroom experiences and observations, and self-brainstorming. The teachers then received training on how to design, develop, and implement robotics-enabled lessons under a design-based research approach for experiential learning, and taught robotics-enabled lessons to a selected student population in classroom settings. The teachers then responded to the survey for the robotics-enabled teaching. For each case (traditional and robotics-enabled), the survey responses were analyzed, and a set of expected learning outcomes of math and science lessons was derived separately. The thematic analysis results showed that the expected learning outcomes for the robotics-enabled lessons were not only related to the educational gains (content knowledge) observed in traditional teaching, but also to the improvements in the behavioral, social, scientific, cognitive, and intellectual aptitudes of the students. Then, a set of metrics and methods were proposed for assessing the learning outcomes separately. To validate the assessment metrics and methods, teachers from different schools taught two selected robotics-enabled lessons (one math, one science) to same grade students, and separately assessed the learning outcomes of each student using the proposed metrics and methods. The learning outcomes were then compared and benchmarked between schools and subjects. The results of a user study with the teachers showed user acceptance, effectiveness, and suitability of the assessment metrics and methods. The proposed scheme of assessing learning outcomes can be used to assess and justify the benefits and advantages of robotics-enabled STEM education, benchmark the outcomes, help improve teaching preparations, motivate decision-makers to confer on robotics-enabled STEM education and curricula development, and promote robotics-enabled STEM education.
Twice-Exceptional Students: Review of Implications for Special and Inclusive Education
Authors: Gierczyk Marcin , Hornby Garry
Published: February 2021

The purpose of this article is to review recent literature on twice-exceptional students and consider implications for their education in the context of the trend towards increased inclusive education for students with disabilities. The review focused on teachers’ experiences and perceptions and the school experiences of twice-exceptional students. Fifteen articles were reviewed, published between 2000 and 2020, selected according to a systematic protocol from two widely used online databases. Findings indicated that the implications that need to be considered were the importance of teacher preparation, the need for a continuum of special education interventions, the need for collaboration with parents and specialists, and teachers needing to focus on developing strengths as much as remediating difficulties. It was concluded that twice-exceptional students can be taught effectively in inclusive education settings as long as they are able to access appropriate strategies and programs from the fields of special education and gifted education.
Quality in Higher Education and Satisfaction among Professors and Students
Authors: Olmos-Gómez María del Carmen , Luque-Suárez Mónica , Ferrara Concetta , Cuevas-Rincón Jesús Manuel
Published: February 2021

The aim of this study was to analyze the significant differences in satisfaction with educational quality in higher education in Italy (Naples) among students and professors. The sample consisted of 501 higher education students and 121 professors, resulting in a total sample size of 622 subjects. Once the quality parameters of the instrument were determined, reliability was confirmed, and data collection was initiated. In order to analyze the results, a test of independent means (Student’s t-test) was performed, interrelating the variables of educational quality, concerning both management and satisfaction with higher education. Based on the results, we concluded that there are significant differences between the group of students and the group of professors, highlighting a higher level of satisfaction with quality reported by students regarding the coordination of teachers and staff in the educational process; therefore, the inclusion of students in the direct management of the center should be more active and an indicator to be taken into account in self-evaluation. Despite the limitations in the sample at the regional level, it offers many possibilities for future research.
Deep Learning Methods for Classification of Certain Abnormalities in Echocardiography
Authors: Wahlang Imayanmosha , Maji Arnab Kumar , Saha Goutam , Chakrabarti Prasun , Jasinski Michal , Leonowicz Zbigniew , Jasinska Elzbieta
Published: February 2021

This article experiments with deep learning methodologies in echocardiogram (echo), a promising and vigorously researched technique in the preponderance field. This paper involves two different kinds of classification in the echo. Firstly, classification into normal (absence of abnormalities) or abnormal (presence of abnormalities) has been done, using 2D echo images, 3D Doppler images, and videographic images. Secondly, based on different types of regurgitation, namely, Mitral Regurgitation (MR), Aortic Regurgitation (AR), Tricuspid Regurgitation (TR), and a combination of the three types of regurgitation are classified using videographic echo images. Two deep-learning methodologies are used for these purposes, a Recurrent Neural Network (RNN) based methodology (Long Short Term Memory (LSTM)) and an Autoencoder based methodology (Variational AutoEncoder (VAE)). The use of videographic images distinguished this work from the existing work using SVM (Support Vector Machine) and also application of deep-learning methodologies is the first of many in this particular field. It was found that deep-learning methodologies perform better than SVM methodology in normal or abnormal classification. Overall, VAE performs better in 2D and 3D Doppler images (static images) while LSTM performs better in the case of videographic images.
Optimal Energy Beamforming to Minimize Transmit Power in a Multi-Antenna Wireless Powered Communication Network
Authors: Hameed Iqra , Tuan Pham-Viet , Camana Mario R. , Koo Insoo
Published: February 2021

In this paper, we study the transmit power minimization problem with optimal energy beamforming in a multi-antenna wireless powered communication network (WPCN). The considered network consists of one hybrid access point (H-AP) with multiple antennae and multiple users with a single antenna each. The H-AP broadcasts an energy signal on the downlink, using energy beamforming to enhance the efficiency of the transmit energy. In this paper, we jointly optimize the downlink time allocation for wireless energy transfer (WET), the uplink time allocation for each user to send a wireless information signal to the H-AP, the power allocation to each user on the uplink, and the downlink energy beamforming vectors while controlling the transmit power at the H-AP. It is challenging to solve this non-convex complex optimization problem because it is numerically intractable and involves high computational complexity. We exploit a sequential parametric convex approximation (SPCA)-based iterative method, and propose optimal and sub-optimal solutions for the transmit power minimization problem. All the proposed schemes are verified by numerical simulations. Through the simulation results, we present the performance of the proposed schemes based on the effect of the number of transmit antennae and the number of users in the proposed WPCN. Through the performance evaluation, we show that the SPCA-based joint optimization solution performance is superior to other solutions.
Neural Network Based Robust Lateral Control for an Autonomous Vehicle
Authors: Swain Subrat Kumar , Rath Jagat J. , Veluvolu Kalyana C.
Published: February 2021

The lateral motion of an Automated Vehicle (AV) is highly affected by the model’s uncertainties and unknown external disturbances during its navigation in adverse environmental conditions. Among the variety of controllers, the sliding mode controller (SMC), known for its robustness towards disturbances, is considered to generate a robust control signal under uncertainties. However, conventional SMC suffers from the issue of high frequency oscillations, called chattering. To address the issue of chattering and reduce the effect of unknown external disturbances in the absence of precise model information, a radial basis function neural network (RBFNN) is employed to estimate the equivalent control. Further, a higher order sliding mode (HOSM) based switching control is proposed in this paper to compensate for the effect of external disturbances. The effectiveness of the proposed controller in terms of lane-keeping and lateral stability is demonstrated through simulation in a high-fidelity Carsim-Matlab Simulink environment under a variety of road and environmental conditions.
Regime Confluence in Automobile Industry Transformation: Boundary Dissolution and Network Reintegration via CASE Vehicles
Authors: Wang Liqiao , Wells Peter
Published: February 2021

Technological innovations in sociotechnical transitions are usually found in market or spatial niches. These novel niches may sometimes emerge and expand, and eventually may erode an established sociotechnical system regime. In this paper, we redefined niche emergence as potentially consequent from the convergence of different regimes. That is, it is proposed that innovative niches may be grounded in established regimes but subsequently expand or bridge to previously distinct and separate other sociotechnical system regimes. However, the extension of overlapping regimes creates new forms of “external” competition for industrial participants inside each regime. This paper therefore proposes that regime–regime confluence may be observed in (1) the boundaries between regimes potentially being broken via emergent new niches; (2) pre-existing local networks being fragmented and reformed into exclusive and/or wider networks; and (3) competitive challenges and pressures arising both from inside and outside the traditional industry. These outcomes are illustrated in this paper with the case of automobility transitions arising from the combination of C (connected), A (autonomous), S (shared), and E (electric) cars. The paper presents an analysis of 340 instances of regime–regime boundary crossing examples over 10 years of data drawn from specialist industry journals and websites. The number and diversity of the validated results show that CASE vehicles are both a cause and consequence of automobile industry transition, and hence that regime–regime confluence is an important neglected source of innovation and structural change.
Analysis of Technical Capabilities, Methodology and Test Results of a Light-Commercial Vehicle Conversion to Battery Electric Powertrain
Authors: Bielaczyc Piotr , Sala Rafal , Meinicke Tomasz
Published: February 2021

This paper describes a holistic development and testing approach for a battery electric vehicle (BEV) prototype based on a self-supporting body platform originating from a vehicle powered by an internal combustion engine. The topic was investigated in relation to the question of whether conversion of existing vehicle platforms is a viable approach in comparison to designing a new vehicle ab initio. The scope of work consisted of the development stage, followed by laboratory and on-road testing to verify the vehicle’s performance and driveability. The vehicle functionality targeted commercial daily use on urban routes. Based on the assumed technical requirements, the vehicle architecture was designed and components specified that included various sub-systems: electric motor powertrain, electronic control unit (ECU), high-voltage battery pack with battery management system (BMS), charging system, high and low voltage wiring harness and electrically driven auxiliary systems. Electric sub-systems were integrated into the existing vehicle on-board controller area network (CAN) bus by means of enhanced algorithms. The test methodology of the prototype electric vehicle included the vehicle range and energy consumption measurement using the EU legislative test cycle. Laboratory testing was performed at different ambient temperatures and for various characteristics of the kinetic energy recovery system. Functional and driveability testing was performed on the road, also including an assessment of overall vehicle durability. Based on the results of testing, it was determined that the final design adopted fulfilled the pre-defined criteria; benchmarking against competing solutions revealed favorable ratings in certain aspects.
The Effect of Antibiotics on Mesophilic Anaerobic Digestion Process of Cattle Manure
Authors: Koniuszewska Izabela , Harnisz Monika , Korzeniewska Ewa , Czatzkowska Małgorzata , Jastrzębski Jan Paweł , Paukszto Łukasz , Bajkacz Sylwia , Felis Ewa , Rusanowska Paulina
Published: February 2021

This study explored the effect of eight antimicrobials on the efficiency of biogas production in the anaerobic digestion (AD) process of cattle manure. The microbiome involved in AD, presence and number of genes mcrA, MSC and MST specific for Archaea, and antibiotic resistance genes (ARGs) concentration in digestate (D) were examined. Supplementation of antibiotics to substrate significantly lowered biogas production. Amoxicillin caused a 75% decrease in CH4 production in comparison with the control samples. Enrofloxacin, tetracycline, oxytetracycline, and chlortetracycline reduced the amount of biogas produced by 36, 39, 45 and 53%, respectively. High-throughput sequencing of 16S rRNA results revealed that bacteria dominated the Archaea microorganisms in all samples. Moreover, antibiotics led to a decrease in the abundance of the genes mcrA, MSC, MST, and induced an increase in the number of tetracyclines resistance genes. Antibiotics decreased the efficiency of the AD process and lowered the quantity of CH4 obtained, while stimulating an increase in the number of ARGs in D. This work reveals how antimicrobials affect the cattle manure AD process and changes in microbial biodiversity, number of functional genes and ARGs in the digestate due to drugs exposure. It also, provides useful, practical information about the AD process.
Numerical Study of Spray-Induced Turbulence Using Industrial Fire-Mitigation Nozzles
Authors: Gai Guodong , Hadjadj Abdellah , Kudriakov Sergey , Mimouni Stephane , Thomine Olivier
Published: February 2021

A numerical investigation of the spray-induced turbulence generated from industrial spray nozzles is carried out to better understand the roles of the nozzle spray on the fires or explosions in different accidental scenarios. Numerical simulations are first validated against experimental data in the single nozzle case using the monodisperse and polydisperse assumption for droplet diameters. The polydispersion of the nozzle spray is proven to be necessary to correctly predict the gas and droplet velocities. The turbulent kinetic energy has dominant values inside the spray cone, decreases rapidly with the vertical distance from the spray nozzle, and is strongly affected by the spray droplet diameter. On the contrary, the integral length scale is found to have high values outside the spray cone. Two interacting sprays injected from different nozzles are then investigated numerically using the validated polydisperse model. The water sprays generated from such industrial nozzles can generate turbulence of high intensity in the near-nozzle region, and this intensity decreases with the distance from the nozzles. A better understanding of the turbulence generated by the spray system can be beneficial for the evaluation of several important phenomena such as explosion enhancement. The guideline values obtained from this investigation of single and double nozzles can be useful for large-scale numerical simulations.
Dynamic Rating Management of Overhead Transmission Lines Operating under Multiple Weather Conditions
Authors: Martinez Raquel , Manana Mario , Arroyo Alberto , Bustamante Sergio , Laso Alberto , Castro Pablo , Minguez Rafael
Published: February 2021

Integration of a large number of renewable systems produces line congestions, resulting in a problem for distribution companies, since the lines are not capable of transporting all the energy that is generated. Both environmental and economic constraints do not allow the building new lines to manage the energy from renewable sources, so the efforts have to focus on the existing facilities. Dynamic Rating Management (DRM) of power lines is one of the best options to achieve an increase in the capacity of the lines. The practical application of DRM, based on standards IEEE (Std.738, 2012) and CIGRE TB601 (Technical Brochure 601, 2014) , allows to find several deficiencies related to errors in estimations. These errors encourage the design of a procedure to obtain high accuracy ampacity values. In the case of this paper, two methodologies have been tested to reduce estimation errors. Both methodologies use the variation of the weather inputs. It is demonstrated that a reduction of the conductor temperature calculation error has been achieved and, consequently, a reduction of ampacity error.
The Role of Simulation and Serious Games in Teaching Concepts on Circular Economy and Sustainable Energy
Authors: de la Torre Rocio , Onggo Bhakti S. , Corlu Canan G. , Nogal Maria , Juan Angel A.
Published: February 2021

The prevailing need for a more sustainable management of natural resources depends not only on the decisions made by governments and the will of the population, but also on the knowledge of the role of energy in our society and the relevance of preserving natural resources. In this sense, critical work is being done to instill key concepts—such as the circular economy and sustainable energy—in higher education institutions. In this way, it is expected that future professionals and managers will be aware of the importance of energy optimization, and will learn a series of computational methods that can support the decision-making process. In the context of higher education, this paper reviews the main trends and challenges related to the concepts of circular economy and sustainable energy. Besides, we analyze the role of simulation and serious games as a learning tool for the aforementioned concepts. Finally, the paper provides insights and discusses open research opportunities regarding the use of these computational tools to incorporate circular economy concepts in higher education degrees. Our findings show that, while efforts are being made to include these concepts in current programs, there is still much work to be done, especially from the point of view of university management. In addition, the analysis of the teaching methodologies analyzed shows that, although their implementation has been successful in favoring the active learning of students, their use (especially that of serious games) is not yet widespread.
A Multi-Channel Fast Impedance Spectroscopy Instrument Developed for Quality Assurance of Super-Capacitors
Authors: Farooq Farhan , Khan Asad , Lee Seung June , Mahad Nadeem Mohammad , Choi Woojin
Published: February 2021

Conventional experimental methods for testing the performance of super-capacitors include the measurement of capacitance through charge and discharge, measurement of equivalent series resistance (ESR) and measurement of self-discharge and the equivalent circuit model (ECM) by electrochemical impedance spectroscopy (EIS). However, the methods are not suitable for the mass production line of supercapacitors since they require a long time for the test and several kinds of different instrument. EIS is an attractive method to evaluate the performance of supercapacitors except that it takes a long time for a single test. In this paper a fast EIS instrument suitable for quality assurance for the mass production of supercapacitors is proposed. In order to reduce the time for the test, a multi-sine sweeping method is used for the EIS test and the results are analyzed by extracting the parameters of the ECM to evaluate the performance of the supercapacitors. The proposed instrument is developed to have multi-channel to further decrease the time for the test with a supercapacitor. It is also presented as to how the extracted parameter values of the ECM can be used to evaluate the performance of the supercapacitor.
Quantifying the Effect of De-Emulsifiers on Acid Treatment in Carbonate Formations
Authors: Elsafih Mohamed , Fahes Mashhad , Teodoriu Catalin
Published: February 2021

Matrix acidizing is a highly successful, effective, and relatively inexpensive approach to enhancing well productivity in carbonate formations. Accordingly, there has been little motivation to address the ways to optimize the acid stimulation process better. Acid-in-oil emulsions that form during this process cause one of the most challenging problems that negatively impact the performance and deliverability, especially when these emulsions are highly stable over extended periods. Such stable emulsions can plug the flow path of oil causing high resistance to flow and potentially reducing well productivity. De-emulsifiers are some of the most widely used acid additives targeting the reduction of emulsion stability. However, there is doubt in the research community on whether there is enough shear mixing that can cause the formation of emulsions inside the rock matrix. Besides, the effectiveness of de-emulsifiers in eliminating such emulsions in the pore space has not been investigated. In the current oil price market, there is a need to be more vigilant regarding the cost of well stimulation and the added value from the various additives. While laboratory work on matrix acidizing in carbonate formations is abundant, the work on oil-saturated samples is rare, and therefore, the effect of emulsions on the acidizing process has not been widely documented. In this work, we present a stacked study of bottle tests and core flooding tests designed to investigate the de-emulsifiers’ role in the rock matrix. The results reveal that (1) emulsion-risk in the pore space is real, and (2) the addition of de-emulsifiers to the acid allows for efficient backflow of oil, revealing an improvement in the performance of the acidizing treatment.
A New Estimate of Sand and Grout Thermal Properties in the Sandbox Experiment for Accurate Validations of Borehole Simulation Codes
Authors: Naldi Claudia , Jahanbin Aminhossein , Zanchini Enzo
Published: February 2021

Ground-coupled heat pumps usually employ fields of borehole heat exchangers (BHEs), which must be designed by suitable models. In order to validate a BHE model, it is advisable to compare the computation results with experimental data. A well-known data set was provided by Beier et al. (Geothermics 2011, 40) through a laboratory model usually called “sandbox”. Several authors proposed estimates of the thermal properties of the sandbox grout and sand. In this paper, we present a new estimate of those properties, obtained by means of 2D finite-element simulations that consider all the details of the experimental setup, including the thin aluminum pipe at the BHE boundary. Our results show that the measured temperatures in the fluid and in the sand can be reproduced very accurately by considering thermal conductivities 0.863 W/(mK) for the grout and 3.22 W/(mK) for the sand, volumetric heat capacities 4.6 MJ/(m3K) for the grout and 3.07 MJ/(m3K) for the sand, and a slightly enhanced heat capacity of the water contained in the BHE. The 2D simulations are validated by comparison with an analytical solution and by 3D simulations.
A Novel Fault Location Method for Power Cables Based on an Unsupervised Learning Algorithm
Authors: Li Mingzhen , Bu Jialong , Song Yupeng , Pu Zhongyi , Wang Yuli , Xie Cheng
Published: February 2021

In order to locate the short-circuit fault in power cable systems accurately and in a timely manner, a novel fault location method based on traveling waves is proposed, which has been improved by unsupervised learning algorithms. There are three main steps of the method: (1) build a matrix of the traveling waves associated with the sheath currents of the cables; (2) cluster the data in the matrix according to its density level and the stability, using Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN); (3) search for the characteristic cluster point(s) of the two branch clusters with the smallest density level to identify the arrival time of the traveling wave. The main improvement is that high-dimensional data can be directly used for the clustering, making the method more effective and accurate. A Power System Computer Aided Design (PSCAD) simulation has been carried out for typical power cable circuits. The results indicate that the hierarchical structure of the condensed cluster tree corresponds exactly to the location relationship between the fault point and the monitoring point. The proposed method can be used for the identification of the arrival time of the traveling wave.
Optimization for Circulating Cooling Water Distribution of Indirect Dry Cooling System in a Thermal Power Plant under Crosswind Condition with Evolution Strategies Algorithm
Authors: Li Zhao , Wei Huimin , Wu Tao , Du Xiaoze
Published: February 2021

Crosswind has an adverse impact on the performance of an indirect dry cooling system. In order to mitigate the adverse influence, this study redistributed the circulating cooling water among air-cooled heat exchanger sectors so that the performance of the indirect dry cooling system could be improved. An evolution strategies algorithm combined with numerical effectiveness-based heat exchanger model was established to minimize the operation costs of the whole system. Based on a 660 MW practical power plant, optimal circulating cooling water operation strategies under varied crosswind speeds and ambient temperatures were calculated to show its application. According to the calculated results, the performance of the indirect dry cooling system could be enhanced by optimizing circulating cooling water distribution under any crosswind speed, especially under high ambient wind speeds. There is a slight promotion of the coal savings with a rise in ambient temperature: improvements of about 5%. The standard coal consumption rate could save as much as 2.50 g/kWh under crosswind speed of 10 m s−1 and ambient temperature of 32 °C, compared to the 0.1 g/kWh under crosswind speed of 2 m s−1 and ambient temperature of 32 °C.
Electromagnetic Field Tests of a 1-MW Wireless Power Transfer System for Light Rail Transit
Authors: Lee Gunbok , Kim Myung , Lee Changmu , Jang Donguk , Lee Byung-Song , Kim Jae
Published: February 2021

The high-power wireless power transfer (WPT) system in railways does not require physical contact to transfer electrical power, is electrically safe, and reduces maintenance costs from wear and tear. However, a high-power system generates a strong magnetic field that can result in problems of electromagnetic field (EMF) exposure and electromagnetic interference (EMI). In this study, EMF and EMI were measured at various positions under in-motion environment conditions for a 1-MW WPT light rail transit system. The measured maximum EMF was 2.41 μT, which is lower than the international guideline of 6.25 μT for the various locations with a potential presence of passengers. The measured EMI also satisfied international standards in the frequency range of 150 kHz–1 GHz.
Drought and Pathogen Effects on Survival, Leaf Physiology, Oxidative Damage, and Defense in Two Middle Eastern Oak Species
Authors: Ghanbary Ehsan , Fathizadeh Omid , Pazhouhan Iman , Zarafshar Mehrdad , Tabari Masoud , Jafarnia Shahram , Parad Ghasem Ali , Bader Martin Karl-Friedrich
Published: February 2021

The charcoal disease agents, Biscogniauxia mediterranea and Obolarina persica are two latent, ascomycetous oak pathogens in the Middle Eastern Zagros forests, where they have devastating effects, particularly during drought. Under greenhouse conditions, we investigated the effects of the two charcoal disease agents individually and in combination with drought on survival, growth, foliar gas-exchange, pigment content, oxidative stress and the antioxidant response of Quercus infectoria and Q. libani, two of the dominant tree species in this region. Commonly, the strongest negative effects emerged in the drought–pathogen interaction treatments. Q. infectoria showed less severe lesions, higher survival, more growth, and less leaf loss than Q. libani under combined biotic and abiotic stress. In both oak species, the combination of pathogen infection and drought resulted in more than 50% reduction in foliar gas-exchange parameters with partial recovery over time in Q. infectoria suggesting a superior defense system. Indeed, enhanced foliar anthocyanin, total soluble protein and glutathione concentrations imply an upregulation of the antioxidant defense system in Q. infectoria under stress while none of these parameters showed a significant treatment response in Q. libani. Consequently, Q. infectoria foliage showed no significant increase in superoxide, lower lipoxygenase activity, and less electrolyte leakage compared to the highly elevated levels seen in Q. libani indicating oxidative damage. Our findings indicate greater drought tolerance and pathogen resilience in Q. infectoria compared to Q. libani. Under future climate scenarios, we therefore expect changes in forest community structure driven by a decline in Q. libani and closely associated organisms.
Effect of Thermal Modification Treatment on Some Physical and Mechanical Properties of Pinus oocarpa Wood
Authors: Herrera-Builes Jhon F. , Sepúlveda-Villarroel Víctor , Osorio Jairo A. , Salvo-Sepúlveda Linette , Ananías Rubén A.
Published: February 2021

This study deals with the effect of heat treatment on Pinus oocarpa specimens from forest plantations in Colombia. The effects of two heat treatments at 170 and 190 °C for 2.5 h in saturated vapor were evaluated based on the color, dimensional stability, air-dry and basic densities, modulus of elasticity (MOE), and modulus of rupture (MOR) in static bending of samples. The evaluations were carried out following the Colombian Technical Standards NTC 290 and 663, and the color changes resulting from heat treatments were monitored using the CIE-Lab, as well as other standards from the literature. The results show that there was 2.4% and 3.3% mass loss of wood modified at 170 and 190 °C, respectively. The air-dry and basic densities were higher in 170 °C treatment than after 190 °C treatment, and the thermal modifications applied increased the dimensional stability of the treated wood. After treatment at 170 and 190 °C, the lightness to darkness (L*) was reduced by 10% and 22%; the a* coordinate increased by 11% and 26%, causing redness in the treated wood; the b* coordinate increased by 14% and 17%; and the values of the wood color saturation (c*) increased by 14% and 18%, respectively. The general color change (ΔE*) increased gradually with the increase in the treatment temperature, resulting in a high color change to a very different color. The bending strength of thermally modified wood was improved and significantly increased to values higher than those of unmodified Pinus oocarpa wood. The high air-dry and basic densities, improved dimensional stability and resistance to bending, and attractive appearance of the treated wood indicate that thermal modification is a promising alternative for the transformation of Pinus oocarpa wood into a raw material with a high added value.
Tree Shape Variability in a Mixed Oak Forest Using Terrestrial Laser Technology: Implications for Mating System Analysis
Authors: Tomșa Vlăduț Remus , Curtu Alexandru Lucian , Niță Mihai Daniel
Published: February 2021

The accuracy of the description regarding tree architecture is crucial for data processing. LiDAR technology is an efficient solution for capturing the characteristics of individual trees. The aim of the present study was to analyze tree shape variability in a mixed oak forest consisting of four European white oak species: Quercus petraea, Q. frainetto, Q. pubescens, and Q. robur. Moreover, we tested for association between tree shape and individual heterozygosity and whether oak trees identified as pollen donors in a previous genetic study have a larger size in terms of crown and trunk characteristics than non-donors. The woody structure of a tree was defined by the quantitative structure model (QSM) providing information about topology (branching structure), geometry, and volume. For extracting the 3D point clouds a high-speed 3D scanner (FARO FocusS 70) was used. The crown variables were strongly correlated to each other, the branch volume being influenced by branch length, maximum branch order, and the number of branches but not influenced by diameter at breast height (DBH), trunk length, trunk volume, or tree height. There was no relationship between the individual heterozygosity based on nuclear microsatellite genetic markers and crown and trunk characteristics, respectively. Branch volume, total area, DBH, trunk volume, and the total volume of tree were significantly larger in pollen donors compared to non-donor Q. petraea trees. Thus, the mean branch volume was more than three times higher. Pollen donors had nearly two and half times larger total area in comparison to non-donor individuals. Our results suggest that a thorough characterization of tree phenotype using terrestrial laser scanning may contribute to a better understanding of mating system patterns in oak forests.
Dynamic Behaviours of a Filament in a Viscoelastic Uniform Flow
Authors: Ma Jingtao , Tian Fang-Bao , Young John , Lai Joseph C. S.
Published: February 2021

The dynamic behaviours of a filament in a viscoelastic uniform flow were investigated by an immersed boundary-lattice Boltzmann method. The effects of the Reynolds numbers (Re, ranging from 10 to 200) and the Weissenberg number (Wi, ranging from 0 to 1.2) on the filament flapping motion and the drag and lift coefficients on the filament were studied. It was found that a higher inertial effect (larger Re) promotes the flapping motion of the filament. In addition, the major effect of the viscoelasticity of the Giesekus fluid is to decrease the critical Reynolds number for the flapping motion of the filament and to promote the flapping motion. The drag coefficient on the filament in a Giesekus uniform flow decreases with the increase of Wi at low Re (Re<100), and experiences oscillations with similar amplitudes at all Wi at a sufficiently high Re (Re>100). In contrast, the viscoelasticity of the FENE-CR fluid increases the critical Reynolds number at lower Wi (Wi<0.8), and shows little influence on the critical Reynolds number at higher Wi (Wi≥0.8). In addition, the viscoelasticity of the FENE-CR fluid hinders the flapping motion of the filament, and increases the drag coefficient on the filament at low Re (Re<100).
Evaluation of Xylooligosaccharides Production for a Specific Degree of Polymerization by Liquid Hot Water Treatment of Tropical Hardwood
Authors: Jang Soo-Kyeong , Kim Jong-Hwa , Choi June-Ho , Cho Seong-Min , Kim Jong-Chan , Kim Hoyong , Choi In-Gyu
Published: February 2021

Eucalyptus pellita is known as attractive biomass, and it has been utilized for eucalyptus oil, furniture, and pulp and paper production that causes a significant amount of byproducts. Liquid hot water treatment depending on combined severity factor (CSF) was subjected to isolate hemicellulose fraction from E. pellita and to produce xylooligosaccharides (XOS). The xylan extraction ratio based on the initial xylan content of the feedstock was maximized up to 77.6% at 170 °C for 50 min condition (CSF: 1.0), which had accounted for XOS purity of 76.5% based on the total sugar content of the liquid hydrolysate. In this condition, the sum of xylobiose, xylotriose, and xylotetraose which has a low degree of polymerization (DP) of 2 to 4 was determined as 80.6% of the total XOS. The highest XOS production score established using parameters including the xylan extraction ratio, XOS purity, and low DP XOS ratio was 5.7 at CSF 1.0 condition. XOS production score evaluated using the CSF is expected to be used as a productivity indicator of XOS in the industry (R-squared value: 0.92).
Participatory Methods in Food Behaviour Research: A Framework Showing Advantages and Disadvantages of Various Methods
Authors: Onwezen Marleen C. , Bouwman Emily P. , van Trijp Hans C. M.
Published: February 2021

A trend is visible in the food literature showing an increasing number of publications on studies that incorporate some form of participant engagement, such as citizen science and community-based participatory research. This “participation trend” will inevitably affect the scientific field of food behaviour research. This new trend is however not only associated with advantages, and a critical reflection on both the advantages and disadvantages is needed. The current article is a position paper that contributes to the literature in two main ways. First, participation is still in the developmental stage. Many different forms, methods and definitions are used. By providing a structured overview of a variety of participatory methods derived from a focused search of the literature on food behaviour, we aim to clarify the relationships between the various forms of participation methods. Second, the involvement of citizens in research is increasingly calling for novel research methods (e.g., voluntary recruitment and active involvement), which may be accompanied by both advantages and disadvantages. We add to the literature by developing a framework that indicates the advantages and disadvantages of participatory methods in food behaviour research. Our study highlights the relevance of differentiating the goal of the researcher (efficiency versus engagement) and the role of citizens (collecting versus creating), thus implying a trade-off between cost-effectiveness and involvement, as well as between data richness and data quality. Our work is a first effort to create structure and guidance within a new area. Our efforts could be used in future research aimed at developing more extensive protocols and tools for the application of participation in research, thereby offering a controlled manner to ensure that research stays abreast of our changing society.
Changing Wheat Bran Structural Properties by Extrusion-Cooking on a Pilot and Industrial Scale: A Comparative Study
Authors: Roye Chiara , Henrion Muriel , Chanvrier Hélène , Loret Chrystel , King Roberto , Lamothe Lisa , Courtin Christophe M.
Published: February 2021

Extrusion-cooking can be used to change the techno–functional and nutrition-related properties of wheat bran. In this study, pilot-scale (BC21) and industrial-scale (BC45) twin-screw extrusion-cooking using different types of extrusion (single-pass, double-pass and acid extrusion-cooking) and process parameters (temperature, moisture) were compared for their impact on wheat bran. When applying the same process settings, the higher strong water-binding capacity, extract viscosity and extractability displayed by bran extruded using the industrial set-up reflected a more considerable wheat bran structure degradation compared to pilot-scale extrusion-cooking. This was attributed to the overall higher specific mechanical energy (SME), pressure and product temperature that were reached inside the industrial extruder. When changing the type of extrusion-cooking from single-pass to double-pass and acid extrusion-cooking, wheat bran physicochemical characteristics evolved in the same direction, irrespective of extruder scale. The differences in bran characteristics were, however, smaller on industrial-scale. Results show that the differentiating power of the latter can be increased by decreasing the moisture content and increasing product temperature, beyond what is possible in the pilot-scale extruder. This was confirmed by using a BC72 industrial-scale extruder at low moisture content. In conclusion, the extruder scale mainly determines the SME that can be reached and determines the potential to modify wheat bran.
Current Perspective of Sialylated Milk Oligosaccharides in Mammalian Milk: Implications for Brain and Gut Health of Newborns
Authors: Hobbs Madalyn , Jahan Marefa , Ghorashi Seyed A. , Wang Bing
Published: February 2021

Human milk oligosaccharides (HMOs) are the third most abundant solid component after lactose and lipids of breast milk. All mammal milk contains soluble oligosaccharides, including neutral milk oligosaccharides (NMOs) without sialic acid (Sia) moieties and acidic oligosaccharides or sialylated milk oligosaccharides (SMOs) with Sia residues at the end of sugar chains. The structural, biological diversity, and concentration of milk oligosaccharides in mammalian milk are significantly different among species. HMOs have multiple health benefits for newborns, including development of immune system, modification of the intestinal microbiota, anti-adhesive effect against pathogens, and brain development. Most infant formulas lack oligosaccharides which resemble HMOs. Formula-fed infants perform poorly across physical and psychological wellbeing measures and suffer health disadvantages compared to breast-fed infants due to the differences in the nutritional composition of breast milk and infant formula. Of these milk oligosaccharides, SMOs are coming to the forefront of research due to the beneficial nature of Sia. This review aims to critically discuss the current state of knowledge of the biology and role of SMOs in human milk, infant formula milks, and milk from several other species on gut and brain health of human and animal offspring.
4mCPred-CNN—Prediction of DNA N4-Methylcytosine in the Mouse Genome Using a Convolutional Neural Network
Authors: Abbas Zeeshan , Tayara Hilal , Chong Kil To
Published: February 2021

Among DNA modifications, N4-methylcytosine (4mC) is one of the most significant ones, and it is linked to the development of cell proliferation and gene expression. To know different its biological functions, the accurate detection of 4mC sites is required. Although we have several techniques for the prediction of 4mC sites in different genomes based on both machine learning (ML) and convolutional neural networks (CNNs), there is no CNN-based tool for the identification of 4mC sites in the mouse genome. In this article, a CNN-based model named 4mCPred-CNN was developed to classify 4mC locations in the mouse genome. Until now, we had only two ML-based models for this purpose; they utilized several feature encoding schemes, and thus still had a lot of space available to improve the prediction accuracy. Utilizing only a single feature encoding scheme—one-hot encoding—we outperformed both of the previous ML-based techniques. In a ten-fold validation test, the proposed model, 4mCPred-CNN, achieved an accuracy of 85.71% and Matthews correlation coefficient (MCC) of 0.717. On an independent dataset, the achieved accuracy was 87.50% with an MCC value of 0.750. The attained results exhibit that the proposed model can be of great use for researchers in the fields of biology and bioinformatics.
Insights into the Transcriptional Regulation of Branching Hormonal Signaling Pathways Genes under Drought Stress in Arabidopsis
Authors: Rolly Nkulu Kabange , Mun Bong-Gyu , Yun Byung-Wook
Published: February 2021

A large number of hormonal biosynthetic or signaling pathways genes controlling shoot branching are widely known for their roles in regulating plant growth and development, operating in synergetic or antagonistic manner. However, their involvement in abiotic stress response mechanism remains unexplored. Initially, we performed an in silico analysis to identify potential transcription binding sites for the basic leucine zipper 62 transcription factor (bZIP62 TF) in the target branching related genes. The results revealed the presence of cis-regulatory elements specific to two bZIP TFs, AtbZIP18 and AtbZIP69, rather than AtbZIP62. Interestingly, these bZIP TFs were previously proposed to be negatively regulated by the AtbZIP62 TF under salinity in Arabidopsis. Therefore, we investigated the transcriptional regulation of more axillary branching (MAX, strigolactone), PIN-FORMED (PINs, auxin carriers), gibberellic acid (GA)-biosynthetic genes as well as isopentenyltransferase (IPT, cytokinin biosynthesis pathway) genes in response to drought stress in Arabidopsis Col-0 wild type. In addition, in the perspective of exploring the transcriptional interplay of the selected genes with the AtbZIP62, we measured their expression by qPCR in the atbzip62 (lacking the AtbZIP62 gene) background under the same conditions. Our findings revealed that the expression of AtMAX2, AtMAX3, and AtMAX4 was differentially regulated by drought stress between the atbzip62 and Col-0 wild type, but not AtMAX1. Similarly, the transcripts accumulation of AtPIN3 and AtPIN7 (known as auxin efflux carriers), and that of the AtAXR1 showed similar regulation patterns in atbzip62. However, AtPIN1 expression was downregulated in Col-0, but no change was observed in atbzip62. Furthermore, AtIPT5 and AtIPT7 exhibited a differential transcripts accumulation pattern in atbzip62 and Col-0 wild type (WT). In the same way, the expression of the GA biosynthetic genes AtGA2ox1 and AtGA20ox2, and that of AtRGA1 were differentially regulated in atbzip62 compared to the Col-0. Meanwhile, AtGA2ox1 showed a similar expression pattern with Col-0. Therefore, all results suggest PIN, MAX, IPT, and GA-biosynthetic genes, which are differentially regulated by AtbZIP62 transcription factor, as emerging candidate genes that could be involved in drought stress response mechanism in Arabidopsis.