bluuebunny/crossref_metadata_2025 huggingface dataset:
Gaining Insights into Conceptual Models: A Graph-Theoretic Querying Approach
Authors: Medvedev Danny , Shani Uri , Dori Dov
Published: January 2021

Modern complex systems include products and services that comprise many interconnected pieces of integrated hardware and software, which are expected to serve humans interacting with them. As technology advances, expectations of a smooth, flawless system operation grow. Model-based systems engineering, an approach based on conceptual models, copes with this challenge. Models help construct formal system representations, visualize them, understand the design, simulate the system, and discover design flaws early on. Modeling tools can benefit tremendously from querying capabilities that enable gaining deep insights into system aspects that direct model observations do not reveal. Querying mechanisms can unveil and explain cause-and-effect phenomena, identify central components, and estimate impacts or risks associated with changes. Being connected networks of system elements, models can be effectively represented as graphs, to which queries are applied. Capitalizing on established graph-theoretic algorithms to solve a large variety of problems can elevate the modeling experience to new levels. To utilize this rich set of capabilities, one must convert the model into a graph and store it in a graph database with no significant loss of information. Applying the appropriate algorithms and translating the query response back to the original intelligible and meaningful diagrammatic and textual model representation is most valuable. We present and demonstrate a querying approach of converting Object-Process Methodology (OPM) ISO 19450 models into graphs, storing them in a Neo4J graph database, and performing queries that answer complex questions on various system aspects, providing key insights into the modeled system or phenomenon and helping to improve the system design.
Properties of a Lightweight Fly Ash–Slag Alkali-Activated Concrete with Three Strength Grades
Authors: Wang Huailiang , Wu Yuhui , Wang Lang , Chen Huihua , Cheng Baoquan
Published: January 2021

Lightweight alkali-activated concrete (LAAC) is a type of highly environmentally friendly concrete, which can provide the benefits of both alkali-activated material and lightweight concrete. The study aimed to investigate the influence of different water/solid (W/S) ratios on the properties of normal-weight/lightweight fly ash–slag alkali-activated concrete manufactured at ambient temperature. The relative performance of the alkali-activated concrete (AAC) mixes with limestone and sintered fly ash lightweight aggregates as the coarse aggregates was also compared to the conventional ordinary Portland cement (OPC) concrete mix in terms of their compressive stress–strain relationship, splitting tensile strength and fracture parameters. The morphologies and microstructure of the four types of interfacial transition zones (ITZs) were characterized by scanning electron microscopy (SEM). Results indicated that the AAC had a higher tensile strength, stress intensity factor, brittleness and lower elastic modulus than its cement counterpart. With the decrease in the W/S ratio, the density, compressive and tensile strength, ultrasonic pulse velocity, fracture energy, brittleness and elastic modulus of the AAC increase. However, the influence of the W/S ratio on the mechanical properties of the LAAC with lightweight porous aggregates was less than that of the normal-weight AAC. Predictive models of the splitting tensile strength, fracture energy and elastic modulus of the AAC were also suggested, which were similar to those of the OPC concrete. Furthermore, the microstructure investigation showed that no wall effect occurred in the ITZ of the AAC. The ITZ structure of the hardened AAC was also more compact and uniform than that of the OPC concrete.
How Is Indoor Air Quality during Sleep? A Review of Field Studies
Authors: Canha Nuno , Teixeira Catarina , Figueira Mónica , Correia Carolina
Published: January 2021

This review aimed to provide an overview of the characterisation of indoor air quality (IAQ) during the sleeping period, based only on real life conditions’ studies where, at least, one air pollutant was considered. Despite the consensual complexity of indoor air, when focusing on sleeping environments, the available scientific literature is still scarce and falls to provide a multipollutants’ characterisation of the air breathed during sleep. This review, following PRISMA’s approach, identified a total of 22 studies that provided insights of how IAQ is during the sleeping period in real life conditions. Most of studies focused on carbon dioxide (77%), followed by particles (PM2.5, PM10 and ultrafines) and only 18% of the studies focused on pollutants such as carbon monoxide, volatile organic compounds and formaldehyde. Despite the high heterogeneity between studies (regarding the geographical area, type of surrounding environments, season of the year, type of dwelling, bedrooms’ ventilation, number of occupants), several air pollutants showed exceedances of the limit values established by guidelines or legislation, indicating that an effort should be made in order to minimise human exposure to air pollutants. For instance, when considering the air quality guideline of World Health Organisation of 10 µg·m−3 for PM2.5, 86% of studies that focused this pollutant registered levels above this threshold. Considering that people spend one third of their day sleeping, exposure during this period may have a significant impact on the daily integrated human exposure, due to the higher amount of exposure time, even if this environment is characterised by lower pollutants’ levels. Improving the current knowledge of air pollutants levels during sleep in different settings, as well as in different countries, will allow to improve the accuracy of exposure assessments and will also allow to understand their main drivers and how to tackle them.
Microglia-Mediated Neurodegeneration in Perinatal Brain Injuries
Authors: Fleiss Bobbi , Van Steenwinckel Juliette , Bokobza Cindy , K. Shearer Isabelle , Ross-Munro Emily , Gressens Pierre
Published: January 2021

Perinatal brain injuries, including encephalopathy related to fetal growth restriction, encephalopathy of prematurity, neonatal encephalopathy of the term neonate, and neonatal stroke, are a major cause of neurodevelopmental disorders. They trigger cellular and molecular cascades that lead in many cases to permanent motor, cognitive, and/or behavioral deficits. Damage includes neuronal degeneration, selective loss of subclasses of interneurons, blocked maturation of oligodendrocyte progenitor cells leading to dysmyelination, axonopathy and very likely synaptopathy, leading to impaired connectivity. The nature and severity of changes vary according to the type and severity of insult and maturation stage of the brain. Microglial activation has been demonstrated almost ubiquitously in perinatal brain injuries and these responses are key cell orchestrators of brain pathology but also attempts at repair. These divergent roles are facilitated by a diverse suite of transcriptional profiles and through a complex dialogue with other brain cell types. Adding to the complexity of understanding microglia and how to modulate them to protect the brain is that these cells have their own developmental stages, enabling them to be key participants in brain building. Of note, not only do microglia help build the brain and respond to brain injury, but they are a key cell in the transduction of systemic inflammation into neuroinflammation. Systemic inflammatory exposure is a key risk factor for poor neurodevelopmental outcomes in preterm born infants. Based on these observations, microglia appear as a key cell target for neuroprotection in perinatal brain injuries. Numerous strategies have been developed experimentally to modulate microglia and attenuate brain injury based on these strong supporting data and we will summarize these.
Nradd Acts as a Negative Feedback Regulator of Wnt/β-Catenin Signaling and Promotes Apoptosis
Authors: Ozalp Ozgun , Cark Ozge , Azbazdar Yagmur , Haykir Betul , Cucun Gokhan , Kucukaylak Ismail , Alkan-Yesilyurt Gozde , Sezgin Erdinc , Ozhan Gunes
Published: January 2021

Wnt/β-catenin signaling controls many biological processes for the generation and sustainability of proper tissue size, organization and function during development and homeostasis. Consequently, mutations in the Wnt pathway components and modulators cause diseases, including genetic disorders and cancers. Targeted treatment of pathway-associated diseases entails detailed understanding of the regulatory mechanisms that fine-tune Wnt signaling. Here, we identify the neurotrophin receptor-associated death domain (Nradd), a homolog of p75 neurotrophin receptor (p75NTR), as a negative regulator of Wnt/β-catenin signaling in zebrafish embryos and in mammalian cells. Nradd significantly suppresses Wnt8-mediated patterning of the mesoderm and neuroectoderm during zebrafish gastrulation. Nradd is localized at the plasma membrane, physically interacts with the Wnt receptor complex and enhances apoptosis in cooperation with Wnt/β-catenin signaling. Our functional analyses indicate that the N-glycosylated N-terminus and the death domain-containing C-terminus regions are necessary for both the inhibition of Wnt signaling and apoptosis. Finally, Nradd can induce apoptosis in mammalian cells. Thus, Nradd regulates cell death as a modifier of Wnt/β-catenin signaling during development.
Topical Collection “Pharmacology of Medicinal Plants”
Authors: Romano Barbara , Lucariello Giuseppe , Capasso Raffaele
Published: January 2021

The use of remedies based on medicinal plants continues to expand rapidly around the world, with many people now resorting to this type of product for the treatment and prevention of several pathologies [...]
DAT1 and Its Psychological Correlates in Children with Avoidant/Restrictive Food Intake Disorder: A Cross-Sectional Pilot Study
Authors: Cimino Silvia , Marzilli Eleonora , Babore Alessandra , Trumello Carmen , Cerniglia Luca
Published: January 2021

International research has underlined the role played by children’s and maternal psychopathological symptoms on the onset of avoidant/restrictive food intake disorder (ARFID) in early childhood. No study has considered the possible interplay between children’s dopamine transporter (DAT1) genotype and methylation, dysregulation problems and maternal psychopathological risk. This study aimed to investigate the complex relationship between these variables, considering the possible mediation role played by children’s DAT1 methylation on the relationship between mothers’ psychopathological risk and children’s dysregulation problems, moderated by children’s DAT1 genotype. Our sample consisted of 94 early children and their mothers, divided into four subgroups, based on children’s ARFID subtypes (irritable/impulsive (I/I), sensory food aversions (SFA), post-traumatic feeding disorders subtypes (PTFD), and a non-clinical group (NC)). We addressed children’s dysregulation problems and maternal psychopathological risk, and collected children’s DNA through buccal swabs. Results showed that children’s 9/x genotype was associated with PTFD and NC groups, whereas the 10/10 genotype was associated with the SFA group, with large effect size. There were significant large differences in the study groups on children’s DAT1 total methylation, children’s dysregulation problems, and maternal psychopathological risk. Children’s DAT1 methylation did not mediate the relationship between mother’s psychopathological risk and children’s dysregulation problems, but there was a significant large direct effect. Children’s 9/x genotype moderated the relationship between maternal psychopathological risk and children’s DAT1 methylation but, respectively, with a large and small effect. Our pilot study suggested that the relationship between children’s DAT1 genotype and methylation, dysregulation problems, and maternal psychopathological risk has a crucial contribution to ARFID.
A Comparison of Laboratory Simulation Methods of Iron Contamination for FCC Catalysts
Authors: Liao Yitao , Liu Tao , Zhao Huihui , Gao Xionghou
Published: January 2021

Two different methods of simulating iron contamination in a laboratory were studied. The catalysts were characterized using X-ray diffraction, N2 adsorption–desorption, and SEM-EDS. The catalyst performance was evaluated using an advanced cracking evaluation device. It was found that iron was evenly distributed in the catalyst prepared using the Mitchell impregnation method and no obvious iron nodules were found on the surface of the catalyst. Iron on the impregnated catalyst led to a strong dehydrogenation capacity and a slight decrease in the conversion and bottoms selectivity. The studies also showed that iron was mainly in the range of 1–5 μm from the edge of the catalyst prepared using the cycle deactivation method. Iron nodules could be easily observed on the surface of the catalyst. The retention of the surface structure in the alumina-rich areas and the collapse of the surface structure in the silica-rich areas resulted in a continuous nodule morphology, which was similar to the highly iron-contaminated equilibrium catalyst. Iron nodules on the cyclic-deactivated catalyst led to a significant decrease in conversion, an extremely high bottoms yield, and a small increase in the dehydrogenation capacity. The nodules and distribution of iron on the equilibrium catalyst could be better simulated by using the cyclic deactivation method.
Microglial Turnover in Ageing-Related Neurodegeneration: Therapeutic Avenue to Intervene in Disease Progression
Authors: Azam Shofiul , Haque Md. Ezazul , Kim In-Su , Choi Dong-Kug
Published: January 2021

Microglia are brain-dwelling macrophages and major parts of the neuroimmune system that broadly contribute to brain development, homeostasis, ageing and injury repair in the central nervous system (CNS). Apart from other brain macrophages, they have the ability to constantly sense changes in the brain’s microenvironment, functioning as housekeepers for neuronal well-being and providing neuroprotection in normal physiology. Microglia use a set of genes for these functions that involve proinflammatory cytokines. In response to specific stimuli, they release these proinflammatory cytokines, which can damage and kill neurons via neuroinflammation. However, alterations in microglial functioning are a common pathophysiology in age-related neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, Huntington’s and prion diseases, as well as amyotrophic lateral sclerosis, frontotemporal dementia and chronic traumatic encephalopathy. When their sentinel or housekeeping functions are severely disrupted, they aggravate neuropathological conditions by overstimulating their defensive function and through neuroinflammation. Several pathways are involved in microglial functioning, including the Trem2, Cx3cr1 and progranulin pathways, which keep the microglial inflammatory response under control and promote clearance of injurious stimuli. Over time, an imbalance in this system leads to protective microglia becoming detrimental, initiating or exacerbating neurodegeneration. Correcting such imbalances might be a potential mode of therapeutic intervention in neurodegenerative diseases.
Significance of NETs Formation in COVID-19
Authors: Janiuk Karolina , Jabłońska Ewa , Garley Marzena
Published: January 2021

Severe contagious respiratory disease—COVID-19—caused by the SARS-CoV-2 coronavirus, can lead to fatal respiratory failure associated with an excessive inflammatory response. Infiltration and spread of SARS-CoV-2 are based on the interaction between the virus’ structural protein S and the cell’s receptor–angiotensin-converting enzyme 2 (ACE2), with the simultaneous involvement of human trans-membrane protease, serine 2 (TMPRSS2). Many scientific reports stress the importance of elevated recruitment and activity of neutrophils, which can form extracellular neutrophil traps (NETs) playing a significant role in the mechanism of combating pathogens, in the pathogenesis of COVID-19. Excessive generation of NETs during prolonged periods of inflammation predisposes for the occurrence of undesirable reactions including thromboembolic complications and damage to surrounding tissues and organs. Within the present manuscript, we draw attention to the impact of NET generation on the severe course of COVID-19 in patients with concurrent cardiovascular and metabolic diseases. Additionally, we indicate the necessity to explore not only the cellular but also the molecular bases of COVID-19 pathogenesis, which may aid the development of dedicated therapies meant to improve chances for the successful treatment of patients. We also present new directions of research into medications that display NETs formation regulatory properties as potential significant therapeutic strategies in the progress of COVID-19.
Interphase Power Flow Control via Single-Phase Elements in Distribution Systems
Authors: Siratarnsophon Piyapath , Cunha Vinicius C. , Barry Nicholas G. , Santoso Surya
Published: January 2021

The capability of routing power from one phase to another, interphase power flow (IPPF) control, has the potential to improve power systems efficiency, stability, and operation. To date, existing works on IPPF control focus on unbalanced compensation using three-phase devices. An IPPF model is proposed for capturing the general power flow caused by single-phase elements. The model reveals that the presence of a power quantity in line-to-line single-phase elements causes an IPPF of the opposite quantity; line-to-line reactive power consumption causes real power flow from leading to lagging phase while real power consumption causes reactive power flow from lagging to leading phase. Based on the model, the IPPF control is proposed for line-to-line single-phase power electronic interfaces and static var compensators (SVCs). In addition, the control is also applicable for the line-to-neutral single-phase elements connected at the wye side of delta-wye transformers. Two simulations on a multimicrogrid system and a utility feeder are provided for verification and demonstration. The application of IPPF control allows single-phase elements to route active power between phases, improving system operation and flexibility. A simple IPPF control for active power balancing at the feeder head shows reductions in both voltage unbalances and system losses.
Erosion Performance of Atmospheric Plasma Sprayed Thermal Barrier Coatings with Diverse Porosity Levels
Authors: Mahade Satyapal , Venkat Abhilash , Curry Nicholas , Leitner Matthias , Joshi Shrikant
Published: January 2021

Thermal barrier coatings (TBCs) prolong the durability of gas turbine engine components and enable them to operate at high temperature. Several degradation mechanisms limit the durability of TBCs during their service. Since the atmospheric plasma spray (APS) processed 7–8 wt.% yttria stabilized zirconia (YSZ) TBCs widely utilized for gas turbine applications are susceptible to erosion damage, this work aims to evaluate the influence of their porosity levels on erosion behavior. Eight different APS TBCs were produced from 3 different spray powders with porosity ranging from 14% to 24%. The as-deposited TBCs were examined by SEM analysis. A licensed software was used to quantify the different microstructural features. Mechanical properties of the as-deposited TBCs were evaluated using micro-indentation technique. The as-deposited TBCs were subjected to erosion tests at different angles of erodent impact and their erosion performance was evaluated. Based on the results, microstructure-mechanical property-erosion performance was correlated. Findings from this work provide new insights into the microstructural features desired for improved erosion performance of APS deposited YSZ TBCs.
A Global Assessment of Parasite Diversity in Galaxiid Fishes
Authors: Paterson Rachel A. , Viozzi Gustavo P. , Rauque Carlos A. , Flores Verónica R. , Poulin Robert
Published: January 2021

Free-living species often receive greater conservation attention than the parasites they support, with parasite conservation often being hindered by a lack of parasite biodiversity knowledge. This study aimed to determine the current state of knowledge regarding parasites of the Southern Hemisphere freshwater fish family Galaxiidae, in order to identify knowledge gaps to focus future research attention. Specifically, we assessed how galaxiid–parasite knowledge differs among geographic regions in relation to research effort (i.e., number of studies or fish individuals examined, extent of tissue examination, taxonomic resolution), in addition to ecological traits known to influence parasite richness. To date, ~50% of galaxiid species have been examined for parasites, though the majority of studies have focused on single parasite taxa rather than assessing the full diversity of macro- and microparasites. The highest number of parasites were observed from Argentinean galaxiids, and studies in all geographic regions were biased towards the highly abundant and most widely distributed galaxiid species, Galaxias maculatus. Parasite diversity generally increased with the number of studies and individual fish examined, however studies which examined parasites from all body tissues could overcome the effects of low study effort. In order to promote further understanding of galaxiid–parasite biodiversity, we provide a series of recommendations, including the use of molecular techniques to verify parasite identity, and highlight the future roles both fish biologists and parasitologists can play.
Environmental and Management Control over the Submontane Grassland Plant Communities in Central Slovakia
Authors: Diviaková Andrea , Stašiov Slavomír , Pondelík Radovan , Pätoprstý Vladimír , Novikmec Milan
Published: January 2021

In Central Europe, submontane grassland plant biodiversity is currently threatened by management intensification as well as by the cessation and abandonment of management activities (extensive grazing and mowing). Although the vegetation of Central European grasslands has been well described by phytosociological papers, there is still a need to improve our understanding of the effect of both management and environment on species richness and community composition. We studied submontane grassland communities in Central Slovakia. Our study showed that both environmental variables and management were important for shaping the submontane grassland species richness and floristic composition. Plant species richness showed a weak negative relationship with soil pH. When grassland management types were analyzed individually, the amount of phosphorus, nitrogen, pH, and altitude were all found to be significantly correlated with plant species richness or diversity. Management type and local environmental factors (i.e., incoming solar radiation) both determined community composition.
Application of Innovative TGA/Chemometric Approach for Forensic Purposes: The Estimation of the Time since Death in Contaminated Specimens
Authors: Risoluti Roberta , Gullifa Giuseppina , Fineschi Vittorio , Frati Paola , Materazzi Stefano
Published: January 2021

Chronothanatology has always been a challenge in forensic sciences. Therefore, the importance of a multidisciplinary approach for the characterization of matrices (organs, tissues, or fluids) that respond linearly to the postmortem interval (PMI) is emerging increasingly. The vitreous humor is particularly suitable for studies aimed at assessing time-related modifications because it is topographically isolated and well-protected. In this work, a novel approach based on thermogravimetry and chemometrics was used to estimate the time since death in the vitreous humor and to collect a databank of samples derived from postmortem examinations after medico–legal evaluation. In this study, contaminated and uncontaminated specimens with tissue fragments were included in order to develop a classification model to predict time of death based on partial least squares discriminant analysis (PLS-DA) that was as robust as possible. Results demonstrate the possibility to correctly predict the PMI even in contaminated samples, with an accuracy not lower than 70%. In addition, the correlation coefficient of the measured versus predicted outcomes was found to be 0.9978, confirming the ability of the model to extend its feasibility even to such situations involving contaminated vitreous humor.
The Profile of Moods States and Athletic Performance: A Meta-Analysis of Published Studies
Authors: Lochbaum Marc , Zanatta Thaís , Kirschling Deylon , May Emily
Published: January 2021

Researchers have extensively examined and reviewed the relationship of the profile of mood states (POMS) with sport performance since the 1970s. Two decades have passed since the last POMS quantitative review. Our overall objective was to quantify the POMS research with competitive athletes with a prospective measured POMS and a sport performance outcome in the published literature. Additionally, we tested potential moderators of the mental health model (i.e., sport duration, type, and skill) with meta-analytic techniques while considering potential risk bias across study sources. Based on a systematic review, the articles were found using EBSCO and comparing these articles with extensive past POMS in sport and exercise bibliographies. Search terms included profile of mood states (POMS) or iceberg profile or the mental health model with sport and performance or sports performance. For selection, articles must have reported data on competitive athletes, an athletic performance outcome, and a valid form of the POMS measured prospectively. After screening more than 600 articles for inclusion, 25 articles provided sufficient data for effect size calculations. The included articles spanned from 1975 to 2011, with 1497 unique participants. Hedges’ g values were generally small for the six POMS scales: tension (−0.21), depression (−0.43), anger (−0.08), vigor (0.38), fatigue (−0.13), and confusion (−0.41). However, the total mood disturbance (TMD) score effect size was medium in magnitude at −0.53. When corrected for potential publication bias, the effect size values increased in magnitude for tension (−0.47), depression (−0.64), vigor (0.44), fatigue (−0.34), and TMD (−0.84). Moderator analyses for Terry’s (1995) propositions and for risk of bias across studies, statistically, resulted in few differences based on conventional statistical significance (p < 0.05). Measured before performance, most of the POMS scales and TMD are reliable predictors of sport performance in competitive athletes across a wide variety of sports and athletic performance outcomes. Morgan’s (1980, 1985) mental health model or iceberg profile minus anger is still a viable method for understanding and improving athletic performances.
Empirical Assessment of Machine Learning Techniques for Software Requirements Risk Prediction
Authors: Naseem Rashid , Shaukat Zain , Irfan Muhammad , Shah Muhammad Arif , Ahmad Arshad , Muhammad Fazal , Glowacz Adam , Dunai Larisa , Antonino-Daviu Jose , Sulaiman Adel
Published: January 2021

Software risk prediction is the most sensitive and crucial activity of Software Development Life Cycle (SDLC). It may lead to the success or failure of a project. The risk should be predicted earlier to make a software project successful. A model is proposed for the prediction of software requirement risks using requirement risk dataset and machine learning techniques. In addition, a comparison is made between multiple classifiers that are K-Nearest Neighbour (KNN), Average One Dependency Estimator (A1DE), Naïve Bayes (NB), Composite Hypercube on Iterated Random Projection (CHIRP), Decision Table (DT), Decision Table/Naïve Bayes Hybrid Classifier (DTNB), Credal Decision Trees (CDT), Cost-Sensitive Decision Forest (CS-Forest), J48 Decision Tree (J48), and Random Forest (RF) achieve the best suited technique for the model according to the nature of dataset. These techniques are evaluated using various evaluation metrics including CCI (correctly Classified Instances), Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Relative Absolute Error (RAE), Root Relative Squared Error (RRSE), precision, recall, F-measure, Matthew’s Correlation Coefficient (MCC), Receiver Operating Characteristic Area (ROC area), Precision-Recall Curves area (PRC area), and accuracy. The inclusive outcome of this study shows that in terms of reducing error rates, CDT outperforms other techniques achieving 0.013 for MAE, 0.089 for RMSE, 4.498% for RAE, and 23.741% for RRSE. However, in terms of increasing accuracy, DT, DTNB, and CDT achieve better results.
Leveraging Machine-Learning for D2D Communications in 5G/Beyond 5G Networks
Authors: Hashima Sherief , ElHalawany Basem M. , Hatano Kohei , Wu Kaishun , Mohamed Ehab Mahmoud
Published: January 2021

Device-to-device (D2D) communication is a promising paradigm for the fifth generation (5G) and beyond 5G (B5G) networks. Although D2D communication provides several benefits, including limited interference, energy efficiency, reduced delay, and network overhead, it faces a lot of technical challenges such as network architecture, and neighbor discovery, etc. The complexity of configuring D2D links and managing their interference, especially when using millimeter-wave (mmWave), inspire researchers to leverage different machine-learning (ML) techniques to address these problems towards boosting the performance of D2D networks. In this paper, a comprehensive survey about recent research activities on D2D networks will be explored with putting more emphasis on utilizing mmWave and ML methods. After exploring existing D2D research directions accompanied with their existing conventional solutions, we will show how different ML techniques can be applied to enhance the D2D networks performance over using conventional ways. Then, still open research directions in ML applications on D2D networks will be investigated including their essential needs. A case study of applying multi-armed bandit (MAB) as an efficient online ML tool to enhance the performance of neighbor discovery and selection (NDS) in mmWave D2D networks will be presented. This case study will put emphasis on the high potency of using ML solutions over using the conventional non-ML based methods for highly improving the average throughput performance of mmWave NDS.
Leveraging a Genetic Algorithm for the Optimal Placement of Distributed Generation and the Need for Energy Management Strategies Using a Fuzzy Inference System
Authors: Katyara Sunny , Shaikh Muhammad Fawad , Shaikh Shoaib , Khand Zahid Hussain , Staszewski Lukasz , Bhan Veer , Majeed Abdul , Shah Madad Ali , Zbigniew Leonowicz
Published: January 2021

With the rising load demand and power losses, the equipment in the utility network often operates close to its marginal limits, creating a dire need for the installation of new Distributed Generators (DGs). Their proper placement is one of the prerequisites for fully achieving the benefits; otherwise, this may result in the worsening of their performance. This could even lead to further deterioration if an effective Energy Management System (EMS) is not installed. Firstly, addressing these issues, this research exploits a Genetic Algorithm (GA) for the proper placement of new DGs in a distribution system. This approach is based on the system losses, voltage profiles, and phase angle jump variations. Secondly, the energy management models are designed using a fuzzy inference system. The models are then analyzed under heavy loading and fault conditions. This research is conducted on a six bus radial test system in a simulated environment together with a real-time Power Hardware-In-the-Loop (PHIL) setup. It is concluded that the optimal placement of a 3.33 MVA synchronous DG is near the load center, and the robustness of the proposed EMS is proven by mitigating the distinct contingencies within the approximately 2.5 cycles of the operating period.
Construction and Modeling of Multi-Circuit Multi-Voltage HVAC Transmission Lines
Authors: Dziendziel Agnieszka , Kocot Henryk , Kubek Paweł
Published: January 2021

A transmission network’s main objective is to continuously supply electrical energy to consumers. This article presents an analysis of the use of multi-circuit, multi-voltage overhead lines as a compromise between ensuring the system’s safe operation by increasing the transmission network capacity and managing the constraints related to its expansion. The considerations presented in this work include the construction of such lines, their operation, and modeling aspects. As part of the study, the potential for improving the environmental conditions around the lines is discussed in terms of the necessary area for their construction and the peak electromagnetic field strength in their vicinity. We also present a mechanical analysis of stress and sag coordination in the individual circuits of these lines. Then, we detail the method for determining the electrical parameters of multi-voltage lines’ series impedances and capacitance. Specific attention is given to the possibility of zero-sequence voltage that occurs in the systems despite the symmetric supply and load of circuits—especially in the circuits with the lowest voltages—that result from the line’s geometric asymmetry. We evaluate the impact of the line’s geometric asymmetry on the power system’s correct operation by determining the asymmetry factors. Finally, the accuracy of using a simplified symmetric model for lines with various geometric asymmetries is analyzed by studying the error of the short-circuit currents.
Identifying Reservoir Features via iSOR Response Behaviour
Authors: Wang Jingyi , Gates Ian
Published: January 2021

To extract viscous bitumen from oil sands reservoirs, steam is injected into the formation to lower the bitumen’s viscosity enabling sufficient mobility for its production to the surface. Steam-assisted gravity drainage (SAGD) is the preferred process for Athabasca oil sands reservoirs but its performance suffers in heterogeneous reservoirs leading to an elevated steam-to-oil ratio (SOR) above that which would be observed in a clean oil sands reservoir. This implies that the SOR could be used as a signature to understand the nature of heterogeneities or other features in reservoirs. In the research reported here, the use of the SOR as a signal to provide information on the heterogeneity of the reservoir is explored. The analysis conducted on prototypical reservoirs reveals that the instantaneous SOR (iSOR) can be used to identify reservoir features. The results show that the iSOR profile exhibits specific signatures that can be used to identify when the steam chamber reaches the top of the formation, a lean zone, a top gas zone, and shale layers.
Sequential Switching Shunt Regulator Parallel Power Processing Control for High Capacitance Solar Arrays
Authors: Blanes José M. , Carrasco José A. , Garrigós Ausiàs , Marroquí David , Torres Cristian
Published: January 2021

This paper presents a new control strategy for reducing the switching losses produced by the use of high parasitic capacitance solar arrays in the sequential switching shunt regulator. Instead of dividing the solar array into equal sections, the proposed strategy is based on two different sections types, low-capacitance and high-capacitance ones. In order to reduce the switching losses and to maintain the original closed-loop response, a novel parallel power processing control strategy is implemented. With this new technique the low-capacitance sections are the only ones that switch at high frequency to regulate the bus while the high-capacitance sections are only connected or disconnected under high load power changes. In addition, the control closed loop delay associated to the time needed to charge the parasitic capacitance has been modelled and a controller modification is proposed to reduce AC performance degradation.
Topology Optimization to Reduce Electromagnetic Force Induced Vibration for the Specific Frequency of PMSM Motor Using Electromagnetic-Structural Coupled Analysis
Authors: Jang Gyeong Uk , Cho Seunghyeon , Moon Jaemin , Jeon Kyunghun , Kim Chang-wan
Published: January 2021

Vibration and noise reduction are very important in electric vehicle driving motors. In this study, topology optimization of housing was performed to reduce vibration in a specific frequency caused by electromagnetic force generated by a permanent magnet synchronous motor (PMSM). The vibration induced by the electromagnetic force of the motor was calculated using electromagnetic-structural coupled analysis. Then, the magnitude of the acceleration for a specific frequency at which peak occurs in the rectangular and circular shape housing concept design model was reduced by using the topology optimization method. As a result, the rectangular and circular shape housing design reduced 92.9% and 96.0%, respectively. Finally, the vibration was effectively reduced while maintaining the electromagnetic characteristics of the motor, for which topology optimization was conducted while not changing the rotor or stator shape design (electromagnetic design factor) but by changing the motor housing shape design (mechanical and structural design factor).
Techniques for Modelling and Optimizing the Mechanical Properties of Natural Fiber Composites: A Review
Authors: Mulenga Timothy K. , Ude Albert U. , Vivekanandhan Chinnasamy
Published: January 2021

The study of natural fiber-based composites through the use of computational techniques for modelling and optimizing their properties has emerged as a fast-growing approach in recent years. Ecological concerns associated with synthetic fibers have made the utilisation of natural fibers as a reinforcing material in composites a popular approach. Computational techniques have become an important tool in the hands of many researchers to model and analyze the characteristics that influence the mechanical properties of natural fiber composites. This recent trend has led to the development of many advanced computational techniques and software for a profound understanding of the characteristics and performance behavior of composite materials reinforced with natural fibers. The large variations in the characteristics of natural fiber-based composites present a great challenge, which has led to the development of many computational techniques for composite materials analysis. This review seeks to infer, from conventional to contemporary sources, the computational techniques used in modelling, analyzing, and optimizing the mechanical characteristics of natural fiber reinforced composite materials.
Pyrrolizidine Alkaloids Disturb Bile Acid Homeostasis in the Human Hepatoma Cell Line HepaRG
Authors: Waizenegger Julia , Glück Josephin , Henricsson Marcus , Luckert Claudia , Braeuning Albert , Hessel-Pras Stefanie
Published: January 2021

1,2-unsaturated pyrrolizidine alkaloids (PAs) belong to a group of secondary plant metabolites. Exposure to PA-contaminated feed and food may cause severe hepatotoxicity. A pathway possibly involved in PA toxicity is the disturbance of bile acid homeostasis. Therefore, in this study, the influence of four structurally different PAs on bile acid homeostasis was investigated after single (24 h) and repeated (14 days) exposure using the human hepatoma cell line HepaRG. PAs induce a downregulation of gene expression of various hepatobiliary transporters, enzymes involved in bile acid synthesis, and conjugation, as well as several transcription regulators in HepaRG cells. This repression may lead to a progressive impairment of bile acid homeostasis, having the potential to accumulate toxic bile acids. However, a significant intracellular and extracellular decrease in bile acids was determined, pointing to an overall inhibition of bile acid synthesis and transport. In summary, our data clearly show that PAs structure-dependently impair bile acid homeostasis and secretion by inhibiting the expression of relevant genes involved in bile acid homeostasis. Furthermore, important biliary efflux mechanisms seem to be disturbed due to PA exposure. These mole-cular mechanisms may play an important role in the development of severe liver damage in PA-intoxicated humans.
Development and Characterization of a Nutritionally Rich Spray-Dried Honey Powder
Authors: Suhag Yogita , Nayik Gulzar Ahmad , Karabagias Ioannis K. , Nanda Vikas
Published: January 2021

In the present study, the spray-dried honey powder enriched with aonla (Emblica officinalis Gaertn) and basil (Ocimum sanctum) extract was developed using drying aids—gum arabic (GA), maltodextrin (MD), and whey protein concentrate (WPC), and then characterized based on particle size distribution, colour, glass transition temperature (Tg), X-ray diffraction, and antioxidant and rheological properties. Results showed the highest Tg (86.13 °C) for WPC based honey powder, which, in turn, resulted in least stickiness as compared to GA and MD based honey powders with Tg 74.53 °C and 68.26 °C, respectively. The dried honey powder with all three carrier agents exhibited a metastable amorphous state as proved by the broader peaks of X-ray diffractograms due to the short drying time, whereas, a peak at 1637 cm−1, attributed to the carbonyl (C=O) stretching, established the ascorbic acid in the studied powder on account of aonla extract. The mean particle diameter significantly (p < 0.05) increased, following the order WPC (60.45 μm) > GA (41.24 μm) > MD (20.06 μm) as carrier agents, which were related to the higher feed viscosity. The colour parameter L* (30.74–45.78) and b* (5.82–11.64) values of the nutritionally rich honey powder were higher due to presence of polyphenols in aonla and basil extracts, which resulted in the formation of dark brown complexes. The antioxidant activity of WPC based fortified honey powder was highest (82.73%), followed by GA (78.15%) and MD (74.85%) based honey powders. A significant (p < 0.05) increase was found in powder recovery, solubility, and dispersibility using the drying aids in the following order: WPC < GA < MD. Furthermore, the storage modulus (G′) was higher than loss modulus (G″) in all honey powders, wherein the WPC containing powder demonstrated maximum value of G′, followed by GA and MD. Finally, the three honey powders were microbiologically stable.
Analyzing the Impact of Vaccine Availability on Alternative Supplier Selection Amid the COVID-19 Pandemic: A cFGM-FTOPSIS-FWI Approach
Authors: Chen Toly , Wang Yu-Cheng , Wu Hsin-Chieh
Published: January 2021

The supply chain disruption caused by the coronavirus disease 2019 (COVID-19) pandemic has forced many manufacturers to look for alternative suppliers. How to choose a suitable alternative supplier in the COVID-19 pandemic has become an important task. To fulfill this task, this research proposes a calibrated fuzzy geometric mean (cFGM)-fuzzy technique for order preference by similarity to ideal solution (FTOPSIS)-fuzzy weighted intersection (FWI) approach. In the proposed methodology, first, the cFGM method is proposed to accurately derive the priorities of criteria. Subsequently, each expert applies the FTOPSIS method to compare the overall performances of alternative suppliers in the COVID-19 pandemic. The sensitivity of an expert to any change in the overall performance of the alternative supplier is also considered. Finally, the FWI operator is used to aggregate the comparison results by all experts, for which an expert’s authority level is set to a value proportional to the consistency of his/her pairwise comparison results. The cFGM-FTOPSIS-FWI approach has been applied to select suitable alternative suppliers for a Taiwanese foundry in the COVID-19 pandemic.
Cognitive Differences and Influencing Factors of Chinese People’s Old-Age Care Responsibility against the Ageing Background
Authors: Wang Yan , Zhang Ruilian , Peng Shengping
Published: January 2021

With the rapid increase in the ageing population (60+) in China since 1999, the problem of supporting the aged is facing increasingly severe challenges. Based on the 2072 valid samples from the Chinese General Social Survey (CGSS) of 2017, a non-sequential multinomial logistic regression model was established to analyse the changing trends and micro-influencing factors of Chinese people’s cognition of old-age care responsibility (COACR). The result shows that offspring responsibility still is a common COACR, but this concept has been gradually weakened and been replaced by the responsibility of the government and the aged. Individual characteristics and relationships with relatives in the models all significantly affect people’s COACR. It is obviously unrealistic for China to completely rely on government and society to provide for the aged. The traditional ethical role of inter-generational responsibility in providing for the aged should be brought into play. Reshaping the inter-generational responsibility ethics of old-age care requires the joint efforts of government, society, families, individuals and other responsible subjects to construct a diversified old-age care service system.
Developing the eMedical Student (eMS)—A Pilot Project Integrating Medical Students into the Tele-ICU during the COVID-19 Pandemic and beyond
Authors: Ho Joshua , Susser Philip , Christian Cindy , DeLisser Horace , Scott Michael J. , Pauls Lynn A. , Huffenberger Ann M. , Hanson C. William , Chandler John M. , Fleisher Lee A. , Laudanski Krzysztof
Published: January 2021

The COVID-19 pandemic has accelerated the demand for virtual healthcare delivery and highlighted the scarcity of telehealth medical student curricula, particularly tele-critical care. In partnership with the Penn E-lert program and the Department of Anesthesiology and Critical Care, the Perelman School of Medicine (PSOM) established a tele-ICU rotation to support the care of patients diagnosed with COVID-19 in the Intensive Care Unit (ICU). The four-week course had seven elements: (1) 60 h of clinical engagement; (2) multiple-choice pretest; (3) faculty-supervised, student-led case and topic presentations; (4) faculty-led debriefing sessions; (5) evidence-based-medicine discussion forum; (6) multiple-choice post-test; and (7) final reflection. Five third- and fourth-year medical students completed 300 h of supervised clinical engagement, following 16 patients over three weeks and documenting 70 clinical interventions. Knowledge of critical care and telehealth was demonstrated through improvement between pre-test and post-test scores. Professional development was demonstrated through post-course preceptor and learner feedback. This tele-ICU rotation allowed students to gain telemedicine exposure and participate in the care of COVID patients in a safe environment.
Effects of Attitude, Barriers/Facilitators, and Visual Differentiation on Oral Mucosa Pressure Ulcer Prevention Performance Intention
Authors: Kang Min Kyeong , Kim Myoung Soo
Published: January 2021

Oral mucosa pressure ulcers (PUs) can result in frequent pain and discomfort, and have negative effects on quality of life. We aimed to examine attitude, barriers/facilitators of oral mucosa PU prevention, the ability to differentiate oral mucosa PU, and to identify factors influencing PU prevention performance intention. This was a cross-sectional descriptive study of 112 nurses in seven tertiary hospitals and three secondary hospitals. The data collection period was from August to December 2018. For data analysis, descriptive statistics, t-test, ANOVA, Pearson’s correlation coefficient, and multiple regression were used. The mean score of attitudes toward oral mucosa PU prevention was 3.74 ± 0.39. Barriers to oral mucosa PU prevention were 5.65 ± 1.66, and facilitators were 5.35 ± 1.34. The mean correct answer rate of visual differentiation ability was 13%. The factors affecting intention to perform oral mucosa PU prevention were facilitators of oral mucosa PU prevention (β = 0.32, p = 0.001) and attitude (β = 0.26, p = 0.005). To increase intention to perform oral mucosa PU prevention, positive attitudes and enhanced facilitators should be encouraged. Therefore, standardized guidelines and strategies, such as educational opportunities and allocation of resources and personnel focused on oral mucosa PU prevention, need to be provided.