bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective Effects of Bee Venom-Derived Phospholipase A2 against Cholestatic Liver Disease in Mice
Authors: Kim Jung-Yeon , Jang Hyo-Jeong , Leem Jaechan , Kim Gyun-Moo
Published: August 2021

Hepatocyte apoptosis and inflammation play important roles in cholestatic liver diseases. Bee venom-derived secretory phospholipase A2 (bvPLA2) has been shown to ameliorate various inflammatory diseases. However, whether bvPLA2 has a therapeutic effect against cholestatic liver disease has not been evaluated. Therefore, we investigated the effects of bvPLA2 on cholestatic liver injury and fibrosis in a murine model of 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet feeding. The administration of bvPLA2 ameliorated liver damage, cholestasis, and fibrosis in DDC diet-fed mice, as assessed by serum biochemical tests and histological examinations. In addition, bvPLA2 reduced myofibroblast accumulation, concomitant with suppression of transforming growth factor-β signaling cascade. The administration of bvPLA2 inhibited hepatocyte apoptosis in DDC diet-fed mice as represented by a reduction in the number of cells stained with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and suppression of caspase-3 activation. Moreover, bvPLA2 reduced cytokine production along with the inhibition of the nuclear factor kappa-B pathway. The number of regulatory T-cells was increased by bvPLA2, while the number of other immune cells, including neutrophils, macrophages, and CD8+ T-cells, was decreased. Our data indicate that the administration of bvPLA2 ameliorates cholestatic liver injury and fibrosis by inhibiting hepatocyte apoptosis and inflammation.
Myasthenia Gravis—An Analysis of Multimodal Evoked Potentials
Authors: Dziadkowiak Edyta , Waliszewska-Prosół Marta , Wieczorek Małgorzata , Bladowska Joanna , Budrewicz Sławomir , Ejma Maria
Published: August 2021

Introduction: The aim of this study is a comprehensive analysis of the parameters of exogenous evoked potentials (visual, brainstem auditory, and somatosensory) in patients with myasthenia gravis (MG), a prototype of both neuromuscular junction disease and autoimmune disease. The study also seeks to isolate electrophysiological changes that may indicate disorders within the central and/or peripheral nervous system. Methods: A total of forty-two consecutive patients with myasthenia gravis (24 women, 18 men) were included in the study. All of the patients underwent EP examination. MR images were also analyzed. Results: In the group of MG patients, the latency of P100 (113.9 ± 13.9; p < 0.0001) VEP, wave III (3.92 ± 0.29; p = 0.015), wave V (5.93 ± 0.32; <0.0001), interlatency III–V (2.00 ± 0.12; p < 0.0001), interlatency I–V (4.20 ± 0.28; p < 0.001) BAEP, and all components of SEP (N9, P10, N13, P16, N20, P22) were significantly longer. Mean wave I and V amplitude BAEP were relatively lower. Conclusions: The results of the study suggest the presence of disturbances in the bioelectric activities of the central and peripheral nervous system in MG patients.
Risk Assessment of Joint Sealing Tape in Joints between Precast Concrete Sandwich Panels Resilient to Climate Change
Authors: Svensson Tengberg Charlotte , Olsson Lars , Hagentoft Carl-Eric
Published: August 2021

Lately, a new technical solution, pre-compressed joint sealing tapes in precast concrete sandwich panel facades, has been introduced in Sweden. Although the consequences of performance failure can go far beyond the component, affecting the building, the introduction has gained little attention in terms of risk assessment in the literature and in industry. Instead, reference cases are used as verification without formal evaluation, potentially leading to serial failure. The aim of this paper was to provide guidance on how a design–build contractor should handle this new technical solution. A risk assessment framework using a design–build contractor’s perspective was applied to the case. The framework addresses new technical solutions or adaption to new conditions (e.g., climate change) with the aim of preventing serial failures. Moisture conditions within the joints were simulated using present and future climates, and probabilities of failure were assessed using the Monte Carlo method. The results of the study included identified risks of failure associated with the solution and factors influencing the probability of failure. A main issue was the exposure of the facade to driving rain but also run-off areas and imperfections in the application of the joint sealing tape. Future climate changes affect performance negatively. In conclusion, the new technical solution might be possible to use if draining potential is ensured in all detailed designs and a set of recommendations, including full-scale testing, is provided for the design–build contractor.
Model Ownership and Intellectual Property Rights for Collaborative Sustainability on Building Information Modeling
Authors: Ardani Jeri Adin , Utomo Christiono , Rahmawati Yani
Published: August 2021

The concept of building information modeling (BIM) requires multidisciplinary collaboration and generates the problem of intellectual property protection for the creator of the model element. Therefore, this research aimed to determine the model ownership factors and intellectual property rights (IPRs) for collaborative sustainability on BIM practices in Indonesia. This research used the qualitative approach of primary data, and questionnaires were distributed to parties involved and experienced with BIM-based projects in Indonesia. The research adopted descriptive and inferential statistics to analyze data obtained from respondents. The results showed that the party that produces the model element is the main factor that owns the model and the IPRs. Meanwhile, the employer will have the right to own the model of BIM in the form of a license, with limited use only for operations, maintenance, and marketing, and they do not have the right to reuse the model for the construction of future projects. This research is expected to contribute to the body of knowledge and provide recommendations for policymaking in construction contracts to better manage BIM-based projects.
Simultaneous Recording of the Uptake and Conversion of Glucose and Choline in Tumors by Deuterium Metabolic Imaging
Authors: Veltien Andor , van Asten Jack , Ravichandran Niveditha , de Graaf Robin A. , De Feyter Henk M. , Oosterwijk Egbert , Heerschap Arend
Published: August 2021

Increased glucose and choline uptake are hallmarks of cancer. We investigated whether the uptake and conversion of [2H9]choline alone and together with that of [6,6′-2H2]glucose can be assessed in tumors via deuterium metabolic imaging (DMI) after administering these compounds. Therefore, tumors with human renal carcinoma cells were grown subcutaneously in mice. Isoflurane anesthetized mice were IV infused in the MR magnet for ~20 s with ~0.2 mL solutions containing either [2H9]choline (0.05 g/kg) alone or together with [6,6′-2H2]glucose (1.3 g/kg). 2H MR was performed on a 11.7T MR system with a home-built 2H/1H coil using a 90° excitation pulse and 400 ms repetition time. 3D DMI was recorded at high resolution (2 × 2 × 2 mm) in 37 min or at low resolution (3.7 × 3.7 × 3.7 mm) in 2:24 min. Absolute tissue concentrations were calculated assuming natural deuterated water [HOD] = 13.7 mM. Within 5 min after [2H9]choline infusion, its signal appeared in tumor spectra representing a concentration increase to 0.3–1.2 mM, which then slowly decreased or remained constant over 100 min. In plasma, [2H9]choline disappeared within 15 min post-infusion, implying that its signal arises from tumor tissue and not from blood. After infusing a mixture of [2H9]choline and [6,6′-2H2]glucose, their signals were observed separately in tumor 2H spectra. Over time, the [2H9]choline signal broadened, possibly due to conversion to other choline compounds, [[6,6′-2H2]glucose] declined, [HOD] increased and a lactate signal appeared, reflecting glycolysis. Metabolic maps of 2H compounds, reconstructed from high resolution DMIs, showed their spatial tumor accumulation. As choline infusion and glucose DMI is feasible in patients, their simultaneous detection has clinical potential for tumor characterization.
Clinical Significance and the Role of Guanylate-Binding Protein 5 in Oral Squamous Cell Carcinoma
Authors: Liu Pei-Feng , Shu Chih-Wen , Lee Cheng-Hsin , Sie Huei-Cin , Liou Huei-Han , Cheng Jiin-Tsuey , Ger Luo-Ping , Chen Chun-Lin , Chen Chien-Chou , Chen Chun-Feng
Published: August 2021

Guanylate binding protein 5 (GBP5) is the interferon (IFN)-inducible subfamily of guanosine triphosphatases (GTPases) and is involved in pathogen defense. However, the role played by GBP5 in cancer development, especially in oral squamous cell carcinoma (OSCC), is still unknown. Herein, next-generation sequencing analysis showed that the gene expression levels of GBP5 were significantly higher in OSCC tissues compared with those found in corresponding tumor adjacent normal tissues (CTAN) from two pairs of OSCC patients. Higher gene expression levels of GBP5 were also found in tumor tissues of 23 buccal mucosal squamous cell carcinoma (BMSCC)/14 tongue squamous cell carcinoma (TSCC) patients and 30 oral cancer patients from The Cancer Genome Atlas (TCGA) database compared with those in CTAN tissues. Immunohistochemical results showed that protein expression levels of GBP5 were also higher in the tumor tissues of 353 OSCC patients including 117 BMSCC, 187 TSCC, and 49 lip squamous cell carcinoma patients. Moreover, TCGA database analysis indicated that high gene expression levels of GBP5 were associated with poor overall survival in oral cancer patients with moderate/poor cell differentiation, and associated with poor disease-free survival in oral cancer patients with moderate/poor cell differentiation and lymph node metastasis. Furthermore, GBP5-knockdowned cells exhibited decreased cell growth, arrest at G1 phase, and decreased invasion/migration. The gene expression of markers for epithelial−mesenchymal transition and cancer stemness was also reduced in GBP5-silenced oral cancer cells. Taken together, GBP5 might be a potential biomarker and therapeutic target for OSCC patients, especially for those with poor cell differentiation and lymph node metastasis.
Hypoxic Jumbo Spheroids On-A-Chip (HOnAChip): Insights into Treatment Efficacy
Authors: Refet-Mollof Elena , Najyb Ouafa , Chermat Rodin , Glory Audrey , Lafontaine Julie , Wong Philip , Gervais Thomas
Published: August 2021

Hypoxia is a key characteristic of the tumor microenvironment, too rarely considered during drug development due to the lack of a user-friendly method to culture naturally hypoxic 3D tumor models. In this study, we used soft lithography to engineer a microfluidic platform allowing the culture of up to 240 naturally hypoxic tumor spheroids within an 80 mm by 82.5 mm chip. These jumbo spheroids on a chip are the largest to date (>750 µm), and express gold-standard hypoxic protein CAIX at their core only, a feature absent from smaller spheroids of the same cell lines. Using histopathology, we investigated response to combined radiotherapy (RT) and hypoxic prodrug Tirapazamine (TPZ) on our jumbo spheroids produced using two sarcoma cell lines (STS117 and SK-LMS-1). Our results demonstrate that TPZ preferentially targets the hypoxic core (STS117: p = 0.0009; SK-LMS-1: p = 0.0038), but the spheroids’ hypoxic core harbored as much DNA damage 24 h after irradiation as normoxic spheroid cells. These results validate our microfluidic device and jumbo spheroids as potent fundamental and pre-clinical tools for the study of hypoxia and its effects on treatment response.
UV-Light-Driven Enhancement of Peroxidase-Like Activity of Mg-Aminoclay-Based Fe3O4/TiO2 Hybrids for Colorimetric Detection of Phenolic Compounds
Authors: Jang Yoon Jung , Bui Vu Khac Hoang , Nguyen Phuong Thy , Lee Young-Chul , Kim Moon Il
Published: August 2021

Light-activated nanozymes possess several advantages, such as light-mediated activity regulation, utilization of molecular oxygen as a green oxidant, and highly enhanced activity; however, the types of light-activated nanozymes are still limited. In this study, we found that Mg aminoclay-based Fe3O4/TiO2 hybrids (MgAC-Fe3O4/TiO2) exhibited peroxidase-like catalytic activity to catalyze the oxidation of the peroxidase substrate 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS) in the presence of H2O2, which was significantly enhanced under ultraviolet (UV)-light irradiation. Compared with MgAC-Fe3O4 and MgAC-TiO2, MgAC-Fe3O4/TiO2 showed around three-fold enhancement in the absorption intensity corresponding to the oxidized ABTS under UV-light irradiation, presumably due to the synergistic effect between Fe3O4 and TiO2, thereby facilitating photocatalytic electron transfer during the catalytic action. In addition, the MgAC-Fe3O4/TiO2 showed vivid stability enhancement in wide range of pH and temperature values compared with natural peroxidase. The UV-light-driven MgAC-Fe3O4/TiO2-based system was successfully applied for the colorimetric detection of phenolic compounds, including pyrocatechol and resorcinol, in a dynamic linear range of 0.15–1.30 mg/mL with a limit of detection as low as 0.1 mg/mL. Further, the system could successfully determine the phenolic compounds in spiked tap water, and thus, it can be used for practical applications. We believe that the UV-light-driven enhancement in the peroxidase-like catalytic performances highlights the potential of MgAC-Fe3O4/TiO2 for detecting phenolic compounds as well as other clinically and environmentally important substances.
Current and Future Implications of COVID-19 among Youth Wheelchair Users: 24-Hour Activity Behavior
Authors: Conners Ryan T. , Bates Lauren C. , Lassalle Patricia Pagan , Zieff Gabriel , Whitehead Paul N. , Stevens Sandra , Killen Lauren , Cochrum Robert , Rodebaugh Kathryn L. , Faghy Mark , Stoner Lee
Published: August 2021

Preventative measures taken worldwide to decrease the transmission of COVID-19 have had a tremendous impact on youth. Following social restrictions, youth with and without physical disabilities are engaging in less physical activity, more increased sedentary behavior, and poor sleep habits. Specifically, youth wheelchair users (YWU) are likely disproportionately affected by COVID- 19 and have a higher risk of contraction due to underlying comorbidities. While we cannot control all of the negative long-term implications of COVID-19 for YWU, participation in positive 24-h activity behaviors can decrease chronic disease risk and the likelihood of long-term complications resulting from infection. This commentary is to extend the discourse on the importance of 24-h activity behaviors by focusing on YWU. Specifically, we discuss the importance of chronic disease prevention, provide a brief overview of 24-h activity behaviors, and outline some of the lessons that can be learned from the COVID-19 pandemic.
Techno-Economic Assessment of IGCC Power Plants Using Gas Switching Technology to Minimize the Energy Penalty of CO2 Capture
Authors: Szima Szabolcs , Arnaiz del Pozo Carlos , Cloete Schalk , Fogarasi Szabolcs , Jiménez Álvaro Ángel , Cormos Ana-Maria , Cormos Calin-Cristian , Amini Shahriar
Published: August 2021

Cost-effective CO2 capture and storage (CCS) is critical for the rapid global decarbonization effort recommended by climate science. The increase in levelized cost of electricity (LCOE) of plants with CCS is primarily associated to the large energy penalty involved in CO2 capture. This study therefore evaluates three high-efficiency CCS concepts based on integrated gasification combined cycles (IGCC): (1) gas switching combustion (GSC), (2) GSC with added natural gas firing (GSC-AF) to increase the turbine inlet temperature, and (3) oxygen production pre-combustion (OPPC) that replaces the air separation unit (ASU) with more efficient gas switching oxygen production (GSOP) reactors. Relative to a supercritical pulverized coal benchmark, these options returned CO2 avoidance costs of 37.8, 22.4 and 37.5 €/ton (including CO2 transport and storage), respectively. Thus, despite the higher fuel cost and emissions associated with added natural gas firing, the GSC-AF configuration emerged as the most promising solution. This advantage is maintained even at CO2 prices of 100 €/ton, after which hydrogen firing can be used to avoid further CO2 cost escalations. The GSC-AF case also shows lower sensitivity to uncertain economic parameters such as discount rate and capacity factor, outperforms other clean energy benchmarks, offers flexibility benefits for balancing wind and solar power, and can achieve significant further performance gains from the use of more advanced gas turbine technology. Based on all these insights, the GSC-AF configuration is identified as a promising solution for further development.
Seasonal Changes in Sleep Patterns in Two Saskatchewan First Nation Communities
Authors: Karunanayake Chandima P. , Ramsden Vivian R. , Bird Clifford , Seeseequasis Jeremy , McMullin Kathleen , Fenton Mark , Skomro Robert , Kirychuk Shelley , Rennie Donna C. , Russell Brooke P. , Koehncke Niels , Smith-Windsor Thomas , King Malcolm , Abonyi Sylvia , Dosman James A. , Pahwa Punam
Published: August 2021

Sleep is crucial for maintaining the recovery and restoration of the body and brain. Less sleep is associated with poor mental and physical performance. Seasonal changes in sleep patterns can be observed. This paper examines seasonal effects on sleep timing, duration, and problems in two Cree First Nation communities in Saskatchewan, Canada. Data were available from a community survey of 588 adults aged 18 years and older (range: 18–78 years) with 44.2% males and 55.8% females. Results are presented using descriptive statistics and a binary logistic-regression model to identify the association between seasonal changes in sleep patterns, and demographic, social, and environmental factors. The participants reported sleeping the least during the spring and summer months and sleeping the most during the fall and winter months. This was further confirmed by sleep hours and the lower proportion of recommended hours of sleep during the spring and summer, and a higher proportion of longer sleep duration during the fall and winter months. There was no significant variation in sleeping onset and wake-up times by season. Overall, there were no significant differences in the prevalence of sleep deprivation, insomnia, and excessive daytime sleepiness by season. When stratified by age group and sex, some differences existed in the prevalence of sleep problems by season. More than two-thirds (68.6%) of the participants reported that there was a change in sleep patterns across seasons, and about 26.0% reported a very or extremely marked change in sleep patterns across seasons. Changes in sleep patterns by season were related to money left at the end of the month and damage caused by dampness in the house.
Effect of In and Pr on the Microstructure and Properties of Low-Silver Filler Metal
Authors: Wu Jie , Xue Songbai , Zhang Peng
Published: August 2021

The novel low-silver 12AgCuZnSn filler metals containing In and Pr were used for flame brazing of copper and 304 stainless steel in this study. The effects of In and Pr content on the melting temperature, wettability, mechanical properties and microstructure of 12AgCuZnSn filler metal were analyzed. The results indicate that the solidus and liquidus temperatures of filler metals decrease with the addition of In. Trace amounts of Pr have little impact on the melting temperature of the low-silver filler metals. In addition, the spreading area of filler metals on copper and 304 stainless steel is improved. The highest shear strength of brazed joint is 427 MPa when the content of In and Pr are 2 wt.% and 0.15 wt.%, respectively. Moreover, it is observed that the trace amount of Pr significantly refines the microstructure of brazed joint matrix. A bright Pr3Cu4Sn4 phase is found in filler metal and brazing seam when the contents of In and Pr are 5 wt.% and 0.5 wt.%, respectively.
Brain Hemorrhage Classification in CT Scan Images Using Minimalist Machine Learning
Authors: Solorio-Ramírez José-Luis , Saldana-Perez Magdalena , Lytras Miltiadis D. , Moreno-Ibarra Marco-Antonio , Yáñez-Márquez Cornelio
Published: August 2021

Over time, a myriad of applications have been generated for pattern classification algorithms. Several case studies include parametric classifiers such as the Multi-Layer Perceptron (MLP) classifier, which is one of the most widely used today. Others use non-parametric classifiers, Support Vector Machine (SVM), K-Nearest Neighbors (K-NN), Naïve Bayes (NB), Adaboost, and Random Forest (RF). However, there is still little work directed toward a new trend in Artificial Intelligence (AI), which is known as eXplainable Artificial Intelligence (X-AI). This new trend seeks to make Machine Learning (ML) algorithms increasingly simple and easy to understand for users. Therefore, following this new wave of knowledge, in this work, the authors develop a new pattern classification methodology, based on the implementation of the novel Minimalist Machine Learning (MML) paradigm and a higher relevance attribute selection algorithm, which we call dMeans. We examine and compare the performance of this methodology with MLP, NB, KNN, SVM, Adaboost, and RF classifiers to perform the task of classification of Computed Tomography (CT) brain images. These grayscale images have an area of 128 × 128 pixels, and there are two classes available in the dataset: CT without Hemorrhage and CT with Intra-Ventricular Hemorrhage (IVH), which were classified using the Leave-One-Out Cross-Validation method. Most of the models tested by Leave-One-Out Cross-Validation performed between 50% and 75% accuracy, while sensitivity and sensitivity ranged between 58% and 86%. The experiments performed using our methodology matched the best classifier observed with 86.50% accuracy, and they outperformed all state-of-the-art algorithms in specificity with 91.60%. This performance is achieved hand in hand with simple and practical methods, which go hand in hand with this trend of generating easily explainable algorithms.
A Model for Tacit Communication in Collaborative Human-UAV Search-and-Rescue
Authors: Hebbar Vijeth , Langbort Cédric
Published: August 2021

Tacit communication can be exploited in human robot interaction (HRI) scenarios to achieve desirable outcomes. This paper models a particular search and rescue (SAR) scenario as a modified asymmetric rendezvous game, where limited signaling capabilities are present between the two players—rescuer and rescuee. We model our situation as a co-operative Stackelberg signaling game, where the rescuer acts as a leader in signaling its intent to the rescuee. We present an efficient game-theoretic approach to obtain the optimal signaling policy to be employed by the rescuer. We then robustify this approach to uncertainties in the rescue topology and deviations in rescuee behavior. The paper thus introduces a game-theoretic framework to model an HRI scenario with implicit communication capacity.
Choosing Strategies to Deal with Artifactual EEG Data in Children with Cognitive Impairment
Authors: Tost Ana , Migliorelli Carolina , Bachiller Alejandro , Medina-Rivera Inés , Romero Sergio , García-Cazorla Ángeles , Mañanas Miguel A.
Published: August 2021

Rett syndrome is a disease that involves acute cognitive impairment and, consequently, a complex and varied symptomatology. This study evaluates the EEG signals of twenty-nine patients and classify them according to the level of movement artifact. The main goal is to achieve an artifact rejection strategy that performs well in all signals, regardless of the artifact level. Two different methods have been studied: one based on the data distribution and the other based on the energy function, with entropy as its main component. The method based on the data distribution shows poor performance with signals containing high amplitude outliers. On the contrary, the method based on the energy function is more robust to outliers. As it does not depend on the data distribution, it is not affected by artifactual events. A double rejection strategy has been chosen, first on a motion signal (accelerometer or EEG low-pass filtered between 1 and 10 Hz) and then on the EEG signal. The results showed a higher performance when working combining both artifact rejection methods. The energy-based method, to isolate motion artifacts, and the data-distribution-based method, to eliminate the remaining lower amplitude artifacts were used. In conclusion, a new method that proves to be robust for all types of signals is designed.
COVID-19’s Impact on Higher Education: A Rapid Review of Early Reactive Literature
Authors: Khan Muzammal Ahmad
Published: August 2021

This rapid systematic review aims to examine emerging evidence on the effects of COVID-19 on educational institutions and assess the prevalence of e-learning changes in the sector. This paper reviews literature on learning, teaching, and assessment approaches adopted since the COVID-19 outbreak, and assesses the impact on the sector, staff, and students, summarizing findings from peer-reviewed articles. It categorizes these into five key themes: (1) digital learning, (2) e-learning challenges, (3) digital transition to emergency virtual assessment (EVA), (4) psychological impact of COVID-19, and (5) creating collaborative cultures. This represents the first systematic review of COVID-19’s impact on education, clarifying current themes being investigated. The author suggests that the term ‘emergency virtual assessment’ (EVA) is now added for future research discussion. Finally, the paper identifies research gaps, including researching the impact on lesser developed countries, the psychological impact of transition, and the important role of leadership and leadership styles during the transition and handling of the pandemic.
What’s in a Grade? Teacher Candidates’ Experiences of Grading in Higher Education: A Phenomenographic Study
Authors: McGrath Cormac , Ståhle Ylva , Geijer Lena
Published: August 2021

This study explores teacher candidates’ experiences of grading in higher education. A phenomenographic approach was adopted and four qualitatively different categories were identified. Grading was experienced as: self-identification, motivation, personal interpretation and academic enculturation. The results indicate that teacher candidates accept existing grading systems but have difficulty interpreting and explaining them, illustrating areas of importance in teacher education and argues that if teacher candidates do not perceive genuine differences in the performance of assessing by grade descriptors, there is a risk that they may develop an insufficient understanding of grading practices.
Context Matters in Gifted Education
Authors: Shore Bruce M.
Published: August 2021

Bruce M. Shore’s research contributions in gifted education have focused on three contexts that impact how giftedness is understood and the instructional environments that serve gifted learners’ educational needs. This article describes these contributions and provides selected examples plus a more complete Supplemental Online bibliography. First, giftedness benefits from being conceptualized in terms of theories that address the development of expertise. Featured expert–gifted parallels include interconnectedness of knowledge, metacognitive processes, perspective taking, active learner roles, affinity for novelty and complexity, and task representation and planning. Illustrative research is described from preschool age through higher education, including connections to creativity research. Second, gifted education benefits when guided by social-constructivist theory of education and its expression in inquiry-based instruction. Examples include building upon learner interests, question asking, collaborative inquiry, and active learner roles. Desirable specific instructional practices are framed by the above theories and by being considered in the contexts of widely recommended and best practices with their research support. Third, gifted education, at all levels including higher education and teacher education, needs to be an integral part of the context of general education. Most specific gifted education practices also work in general education, including learning high-level skills within subject matter. Nineteen examples are cited about how gifted education contributes to the quality of general education.
MSB R-CNN: A Multi-Stage Balanced Defect Detection Network
Authors: Xu Zhihua , Lan Shangwei , Yang Zhijing , Cao Jiangzhong , Wu Zongze , Cheng Yongqiang
Published: August 2021

Deep learning networks are applied for defect detection, among which Cascade R-CNN is a multi-stage object detection network and is state of the art in terms of accuracy and efficiency. However, it is still a challenge for Cascade R-CNN to deal with complex and diverse defects, as the widely varied shapes of defects lead to inefficiency for the traditional convolution filter to extract features. Additionally, the imbalance in features, losses and samples cause lower accuracy. To address the above challenges, this paper proposes a multi-stage balanced R-CNN (MSB R-CNN) for defect detection based on Cascade R-CNN. Firstly, deformable convolution is adopted in different stages of the backbone network to improve its adaptability to the varying shapes of the defect. Then, the features obtained by the backbone network are refined and enhanced by the balanced feature pyramid. To overcome the imbalance of classification and regression loss, the balanced L1 loss is applied at different stages to correct it. Finally, for the sample selection, the interaction of union (IoU) balanced sampler and the online hard example mining (OHEM) sampler are combined at different stages to make the sampling more reasonable, which can bring a better accuracy and convergence effect to the model. The results of our experiments on the DAGM2007 dataset has shown that our network (MSB R-CNN) can achieve a mean average precision (mAP) of 67.5%, an increase of 1.5% mAP, compared to Cascade R-CNN.
Energy Management Method of Hybrid AC/DC Microgrid Using Artificial Neural Network
Authors: Kang Kyung-Min , Choi Bong-Yeon , Lee Hoon , An Chang-Gyun , Kim Tae-Gyu , Lee Yoon-Seong , Kim Mina , Yi Junsin , Won Chung-Yuen
Published: August 2021

This paper proposes an artificial neural network (ANN)-based energy management system (EMS) for controlling power in AC–DC hybrid distribution networks. The proposed ANN-based EMS selects an optimal operating mode by collecting data such as the power provided by distributed generation (DG), the load demand, and state of charge (SOC). For training the ANN, profile data on the charging and discharging amount of ESS for various distribution network power situations were prepared, and the ANN was trained with an error rate within 10%. The proposed EMS controls each power converter in the optimal operation mode through the already trained ANN in the grid-connected mode. For the experimental verification of the proposed EMS, a small-scale hybrid AD/DC microgrid was fabricated, and simulations and experiments were performed for each operation mode.
A Novel Power Sharing Strategy Based on Virtual Flux Droop and Model Predictive Control for Islanded Low-Voltage AC Microgrids
Authors: Khanabdal Saheb , Banejad Mahdi , Blaabjerg Frede , Hosseinzadeh Nasser
Published: August 2021

The droop control scheme based on Q − ω and P − V characteristics is conventionally employed to share the load power among sources in an islanded low-voltage microgrid with resistive line impedances. However, it suffers from poor active power sharing, and is vulnerable to sustained deviations in frequency and voltage. Therefore, accurate power sharing and maintaining the frequency and voltage in the desired ranges are challenging. This paper proposes a novel microgrid control strategy to address these issues. The proposed strategy consists of a virtual flux droop and a model predictive control, in which the virtual flux is the time integral of the voltage. Firstly, the novel virtual flux droop control is proposed to accurately control the power sharing among DGs. Then, the model predictive flux control is employed to generate the appropriate switching signals. The proposed strategy is simple without needing multiple feedback control loops. In addition, pulse width modulation is not required and tuning challenges for PI regulators are avoided. In order to evaluate the effectiveness of the proposed microgrid control strategy, simulation analysis is carried out in Matlab/Simulink software environment. The results show that accurate power sharing is achieved while a good dynamic response is provided. Furthermore, the voltage and frequency deviations are significantly improved.
Effect of the Pyrolysis Process Applied to Waste Branches Biomass from Fruit Trees on the Calorific Value of the Biochar and Dust Explosivity
Authors: Saletnik Bogdan , Bajcar Marcin , Saletnik Aneta , Zaguła Grzegorz , Puchalski Czesław
Published: August 2021

The article discusses the findings related to the calorific value as well as the explosion and combustion parameters of dust from the raw biomass of fruit trees, i.e., apple, cherry, and pear branches, and from biochars produced using this type of biomass during pyrolysis processes conducted under various conditions. The plant biomass was thermally processed at 400, 450, or 500 °C for a duration of 5, 10, or 15 min. The study aimed to identify the calorific value of the biomass obtained from waste produced in orchards and to estimate the explosion hazard during the processing of such materials and during the storage of the resulting solid fuels. Tests were conducted to assess the total contents of carbon, ash, nitrogen, hydrogen, and volatile substances as well as the calorific value. The findings show a significant effect of the thermal transformation of fruit tree branches on the calorific value of the biochars that were produced. It was found that the mean calorific value of all of the biochars was increased by 62.24% compared to the non-processed biomass. More specifically, the mean calorific values of the biochars produced from apple, cherry, and pear branches amounted to 27.90, 28.75, and 26.84 MJ kg−1, respectively. The maximum explosion pressure Pmax measured for the dust from the biomass and for the biochars was in the range 7.56–7.8 and 7.95–11.72 bar, respectively. The maximum rate of pressure rose over time (dp/dt)max in the case of the dust from the biomass, which was in the range of 274.77–284.97 bar s−1, and the dust from biochar amounted to 282.05–353.41 bar s−1. The explosion index Kst max measured for non-processed biomass and biochars was found to range from 74.46 to 77.23 and from 76.447 to 95.77 bar s−1, respectively. It was also shown that a change in the temperature and duration of the pyrolysis process affected the quality of the biochars that were obtained. The findings show that pyrolysis, as a method of plant biomass processing, positively affects the calorific value of the products and does not lead to an increased risk of explosion during the treatment and storage of such materials. It is necessary, however, to continue research on biomass processing in order to develop practices that adequately ensure safety during the production of novel fuels.
Temperature Estimation of SiC Power Devices Using High Frequency Chirp Signals
Authors: Lu Xiang , Pickert Volker , Al-Greer Maher , Chen Cuili , Wang Xiang , Tsimenidis Charalampos
Published: August 2021

Silicon carbide devices have become increasingly popular in electric vehicles, predominantly due to their fast-switching speeds, which allow for the construction of smaller power converters. Temperature sensitive electrical parameters (TSEPs) can be used to determine the junction temperature, just like silicon-based power switches. This paper presents a new technique to estimate the junction temperature of a single-chip silicon carbide (SiC) metal–oxide–semiconductor field-effect transistor (MOSFET). During off-state operation, high-frequency chirp signals below the resonance frequency of the gate-source impedance are injected into the gate of a discrete SiC device. The gate-source voltage frequency response is captured and then processed using the fast Fourier transform. The data is then accumulated and displayed over the chirp frequency spectrum. Results show a linear relationship between the processed gate-source voltage and the junction temperature. The effectiveness of the proposed TSEPs is demonstrated in a laboratory scenario, where chirp signals are injected in a stand-alone biased discrete SiC module, and in an in-field scenario, where the TSEP concept is applied to a MOSFET operating in a DC/DC converter.
Oscillating Wall Jets for Active Flow Control in a Laboratory Fume Hood—Experimental Investigations
Authors: Liebsch Juergen , Paschereit Christian Oliver
Published: August 2021

Wall jets are applied to reduce flow separation and recirculation of the airflow entering the inner space of a laboratory fume hood through its front opening. The flow separation in the hood was further reduced by introducing a self-induced oscillatory motion using fluidic oscillators. The design of the oscillators integrated in the predetermined contour are based on numerical simulations. The effect of the steady and unsteady wall jet was investigated experimentally using flow visualization, particle image velocimetry (PIV), and containment measurements. The oscillatory wall-jet led to reduction of flow separation and recirculation even at lower injection volume flows. In consequence, the usage of fluidic oscillators for a laboratory fume hood increases the energy efficiency of the system without reducing the safety of the laboratory fume hood.
The Effect of Different Additives on the Hydration and Gelation Properties of Composite Dental Gypsum
Authors: Ma Liang , Xie Qianting , Evelina Amutenya , Long Wenjun , Ma Cunfa , Zhou Fengshan , Cha Ruitao
Published: August 2021

Dental mold gypsum materials require fine powder, appropriate liquidity, fast curing, and easy-to-perform clinical operations. They require low linear expansion coefficient and high strength, reflecting the master model and facilitating demolding. In this article, the suitable accelerators and reinforcing agents were selected as additives to modify dental gypsum. The main experimental methods used were to compare the trends of linear expansion coefficients of several commercially available dental gypsum products over 72 h and to observe the cross-sectional microstructure of cured bodies before and after dental gypsum modification using scanning electron microscopy. By adjusting the application of additives, the linear expansion coefficient of dental gypsum decreased from 0.26% to 0.06%, while the flexural strength increased from 6.7 MPa to 7.4 MPa at 2 h. Formulated samples showed good stability and gelation properties with linear expansion completed within 12 h. It is indicated that the performance of dental gypsum materials can be improved by adding additives and nanomaterials, which provided a good reference for clinical preparation of high-precision dental prosthesis.
Mechanisms Underlying the Suppression of Chromosome Rearrangements by Ataxia-Telangiectasia Mutated
Authors: Yamauchi Motohiro
Published: August 2021

Chromosome rearrangements are structural variations in chromosomes, such as inversions and translocations. Chromosome rearrangements have been implicated in a variety of human diseases. Ataxia-telangiectasia (A-T) is an autosomal recessive disorder characterized by a broad range of clinical and cellular phenotypes. At the cellular level, one of the most prominent features of A-T cells is chromosome rearrangement, especially that in T lymphocytes. The gene that is defective in A-T is ataxia-telangiectasia mutated (ATM). The ATM protein is a serine/threonine kinase and plays a central role in the cellular response to DNA damage, particularly DNA double-strand breaks. In this review, the mechanisms by which ATM suppresses chromosome rearrangements are discussed.
The Impact of Public Reporting Schemes and Market Competition on Hospital Efficiency
Authors: Han Ahreum , Lee Keon-Hyung
Published: August 2021

In the wake of growing attempts to assess the validity of public reporting, much research has examined the effectiveness of public reporting regarding cost or quality of care. However, relatively little is known about whether transparency through public reporting significantly influences hospital efficiency despite its emerging expectations for providing value-based care. This study aims to identify the dynamics that transparency brought to the healthcare market regarding hospital technical efficiency, taking the role of competition into account. We compare the two public reporting schemes, All-Payer Claims Database (APCD) and Hospital Compare. Employing Data Envelopment Analysis (DEA) and a cross-sectional time-series Tobit regression analysis, we found that APCD is negatively associated with hospital technical efficiency, while hospitals facing less competition responded significantly to increasingly transparent information by enhancing their efficiency relative to hospitals in more competitive markets. We recommend that policymakers take market mechanisms into consideration jointly with the introduction of public reporting schemes in order to produce the best outcomes in healthcare.
Can We Manage Behavioral Problems through the Development of Children’s Social-Emotional Regulated Behavior? Longitudinal Study of a Preschool Program
Authors: Justicia-Arráez Ana , Pichardo María Carmen , Romero-López Miriam , Alba Guadalupe
Published: August 2021

Behavioral problems are early indicators of antisocial behavior and should be targeted from a preventive perspective from early childhood. The purpose of the study was to analyze the effectiveness of the AC1 preschool program that develops social-emotional skills that facilitate the adjustment and regulation of the person. A total of 102 children aged 3–4 years old participated in the research, 52 belonging to the experimental group and 49 to the control group. Program-trained skills (ROAC-3), social skills (PKBS-2), and externalizing problems (CBCL C-TRF) were assessed in the pre- and post-intervention phase. Data analysis was carried out using a generalized linear mixed model analysis (GLMM). The results show that the children in the experimental group scored higher on the variables trained by the program and on social skills than those in the control group. They also obtained lower scores in the observed externalizing problems. The effect of the program was high in the emotion identification and expression, communication skills, prosocial behaviors (sharing and helping), problem-solving, and social interaction. Social-emotional learning in early childhood is essential for the prevention of behavioral problems to facilitate the development of adjusted and regulated behavior. Thus, preschool programs could play a key role.
Parental Awareness and Attitude about Childhood Immunization in Riyadh, Saudi Arabia: A Cross-Sectional Study
Authors: Alshammari Shuaa Z. , AlFayyad Isamme , Altannir Youssef , Al-Tannir Mohamad
Published: August 2021

Parental beliefs about vaccination are one of the main factors in reaching high vaccination rates. This cross-sectional study aims to assess the awareness and attitudes regarding routine childhood immunization among Saudi parents in Riyadh, Saudi Arabia. This survey, with a pretested 18-item questionnaire, was conducted on parents having at least one child from Riyadh, Saudi Arabia, between 1 May 2019 and 1 November 2019. The validated questionnaire consisted of three sections; participants’ demographics, awareness, and attitude regarding the immunization of their children. In total, 1200 parents participated in the study, 883 (73.3%) of the parents scored a good knowledge of childhood immunization, and 93% knew that routine vaccination protects children from infectious diseases and their complications. Around 10% stated that immunization can cause autism. Only parents in age groups 30–39 and 40–49 were 1.76 (p < 0.05) times and 1.92 (p < 0.05) times, respectively, more likely to exhibit good knowledge. About 522 (43.6) of the parents attained a positive attitude toward immunization. Adherence to the immunization schedule was confirmed important by 93%, while 91% presumed that immunization keeps their children healthy. Additionally, immunization was perceived as important by 94% of parents and only 8% agreed that immunization is prohibited by religion. Females were 1.45 (p < 0.05) times more likely to exhibit positive attitudes than males. Parents have good knowledge and a positive attitude towards child immunization. However, parental education should be focused on the fact that religion supports immunization, and more awareness should be focused on the lack of correlation between autism and vaccination.
Modeling the Dynamic Linkage between Tourism Development, Technological Innovation, Urbanization and Environmental Quality: Provincial Data Analysis of China
Authors: Chenghu Zhang , Arif Muhammad , Shehzad Khurram , Ahmad Mahmood , Oláh Judit
Published: August 2021

This study investigates the linkage between tourism development, technological innovation, urbanization and environmental degradation across 30 provinces of China. Based on data from 2001 to 2018, the study used an advanced economic methodology for the long-run estimate, the Augmented Mean Group (AMG) estimator, which accounts for heterogeneity in slope parameters and dependencies across countries. The empirical results show that tourism development degrades environmental quality, while technological innovation mitigates carbon emissions. Further, findings show that urbanization increases carbon emissions, while an inverted U-shaped relationship exists between economic growth and environmental degradation, implying the existence of EKC in China. Further, the Dumitrescu–Hurlin panel causality test shows that any policy aimed at tourism development or technological innovation would substantially contribute to environmental degradation, but not the other way round.
Analyzing Influencing Factors of Transfer Passenger Flow of Urban Rail Transit: A New Approach Based on Nested Logit Model Considering Transfer Choices
Authors: Zhu Zhenjun , Zeng Jun , Gong Xiaolin , He Yudong , Qiu Shucheng
Published: August 2021

With the continuous improvement of the operation line network of urban rail transit, analyzing influencing factors of transfer passenger flow of urban rail transit is critical to improve the transfer demand analysis of urban rail transit. Using data collected from questionnaires, transfer passenger flow surveys and smart cards, this study proposes an approach base on nested logit passenger flow assignment model considering transfer choice behaviours of passengers. The transfer passenger flow at seven transfer stations in Nanjing is obtained. Subsequently, this study investigates the potential influencing factors of transfer passenger flow, including the node degree, geographic location (located in the city center, urban fringe, suburbs or suburban fringe), economic location (distance from the city center) and transportation locations (if it is close to a transportation hub or in combination with the hub) of rail transit transfer stations. The results indicate that a positive correlation between the transfer passenger flow and the node degrees of transfer stations. However, the relationship between transfer passenger flow and the economic, geographic, and transportation locations of transfer stations is not clear. The finding have reference value for the network design of rail transit transfer stations and transfer facilities, and provide reference for the analysis of passenger flow under network operation.