bluuebunny/crossref_metadata_2025 huggingface dataset:
The Imaging of Guard Cells of thioglucosidase (tgg) Mutants of Arabidopsis Further Links Plant Chemical Defence Systems with Physical Defence Barriers
Authors: Ahuja Ishita , Kissen Ralph , Hoang Linh , Sporsheim Bjørnar , Halle Kari K. , Wolff Silje Aase , Ahmad Samina Jam Nazeer , Ahmad Jam Nazeer , Bones Atle M.
Published: January 2021

The glucosinolate-myrosinase system is a well-known plant chemical defence system. Two functional myrosinase-encoding genes, THIOGLUCOSIDASE 1 (TGG1) and THIOGLUCOSIDASE 2 (TGG2), express in aerial tissues of Arabidopsis. TGG1 expresses in guard cells (GCs) and is also a highly abundant protein in GCs. Recently, by studying wild type (WT), tgg single, and double mutants, we showed a novel association between the glucosinolate-myrosinase system defence system, and a physical barrier, the cuticle. In the current study, using imaging techniques, we further analysed stomata and ultrastructure of GCs of WT, tgg1, tgg2 single, and tgg1 tgg2 double mutants. The tgg mutants showed distinctive features of GCs. The GCs of tgg1 and tgg1 tgg2 mutants showed vacuoles that had less electron-dense granular material. Both tgg single mutants had bigger stomata complexes. The WT and tgg mutants also showed variations for cell wall, chloroplasts, and starch grains of GCs. Abscisic acid (ABA)-treated stomata showed that the stomatal aperture was reduced in tgg1 single and tgg1 tgg2 double mutants. The data provides a basis to perform comprehensive further studies to find physiological and molecular mechanisms associated with ultrastructure differences in tgg mutants. We speculate that the absence of myrosinase alters the endogenous chemical composition, hence affecting the physical structure of plants and the plants’ physical defence barriers.
The Potentiation of Anti-Tumor Immunity by Tumor Abolition with Alpha Particles, Protons, or Carbon Ion Radiation and Its Enforcement by Combination with Immunoadjuvants or Inhibitors of Immune Suppressor Cells and Checkpoint Molecules
Authors: Keisari Yona , Kelson Itzhak
Published: January 2021

The delivery of radiation therapy (RT) for cancer with intent to cure has been optimized and standardized over the last 80 years. Both preclinical and clinical work emphasized the observation that radiation destroys the tumor and exposes its components to the immune response in a mode that facilitates the induction of anti-tumor immunity or reinforces such a response. External beam photon radiation is the most prevalent in situ abolition treatment, and its use exposed the “abscopal effect”. Particle radiotherapy (PRT), which has been in various stages of research and development for 70 years, is today available for the treatment of patients in the form of alpha particles, proton, or carbon ion radiotherapy. Charged particle radiotherapy is based on the acceleration of charged species, such as protons or carbon-12, which deposit their energy in the treated tumor and have a higher relative biological effectiveness compared with photon radiation. In this review, we will bring evidence that alpha particles, proton, or carbon ion radiation can destroy tumors and activate specific anti-tumor immune responses. Radiation may also directly affect the distribution and function of immune cells such as T cells, regulatory T cells, and mononuclear phagocytes. Tumor abolition by radiation can trigger an immune response against the tumor. However, abolition alone rarely induces effective anti-tumor immunity resulting in systemic tumor rejection. Immunotherapy can complement abolition to reinforce the anti-tumor immunity to better eradicate residual local and metastatic tumor cells. Various methods and agents such as immunoadjuvants, suppressor cell inhibitors, or checkpoint inhibitors were used to manipulate the immune response in combination with radiation. This review deals with the manifestations of particle-mediated radiotherapy and its correlation with immunotherapy of cancer.
PD-L1 Protein Expression in Middle Eastern Breast Cancer Predicts Favorable Outcome in Triple-Negative Breast Cancer
Authors: Parvathareddy Sandeep Kumar , Siraj Abdul K. , Ahmed Saeeda O. , Ghazwani Laila Omar , Aldughaither Saud M. , Al-Dayel Fouad , Tulbah Asma , Ajarim Dahish , Al-Kuraya Khawla S.
Published: January 2021

Programmed cell-death ligand 1 (PD-L1) has been shown to induce potent T-cell mediated anti-tumoral immunity. The significance of PD-L1 expression in the prognosis of breast cancer (BC) remains controversial and its prevalence and prognostic value in breast cancer from Middle Eastern ethnicity is lacking. A total of 1003 unselected Middle Eastern breast cancers were analyzed for PD-L1 expression using immunohistochemistry. PD-L1 expression, seen in 32.8% (329/1003) of cases, was significantly associated with poor prognostic indicators such as younger patients, high-grade tumors, estrogen-receptor (ER)-negative, progesterone-receptor (PR)-negative, and triple-negative breast cancers (TNBC) as well as high Ki-67 index. We also found a significant association between PD-L1 expression and deficient mismatch repair protein expression. No association was found between PD-L1 expression and clinical outcome. However, on further subgroup analysis, PD-L1 expression was found to be an independent marker for favorable overall survival and recurrence-free survival in TNBC. In conclusion, we demonstrated strong association between PD-L1 and mismatch repair deficiency in Middle Eastern BC patients and that PD-L1 overexpression in tumor cells was an independent prognostic marker in TNBCs from Middle Eastern ethnicity. Overall, these findings might help in the development of more appropriate treatment strategies for BC in Middle Eastern population.
Natural Compounds of Marine Origin as Inducers of Immunogenic Cell Death (ICD): Potential Role for Cancer Interception and Therapy
Authors: Sansone Clementina , Bruno Antonino , Piscitelli Concetta , Baci Denisa , Fontana Angelo , Brunet Christophe , Noonan Douglas M. , Albini Adriana
Published: January 2021

Regulated cell death (RCD) has always been considered a tolerogenic event. Immunogenic cell death (ICD) occurs as a consequence of tumour cell death accompanied by the release of damage-associated molecular patterns (DAMPs), triggering an immune response. ICD plays a major role in stimulating the function of the immune system in cancer during chemotherapy and radiotherapy. ICD can therefore represent one of the routes to boost anticancer immune responses. According to the recommendations of the Nomenclature Committee on Cell Death (2018), apoptosis (type I cell death) and necrosis (type II cell death) represent are not the only types of RCD, which also includes necroptosis, pyroptosis, ferroptosis and others. Specific downstream signalling molecules and death-inducing stimuli can regulate distinct forms of ICD, which develop and promote the immune cell response. Dying cells deliver different potential immunogenic signals, such as DAMPs, which are able to stimulate the immune system. The acute exposure of DAMPs can prime antitumour immunity by inducing activation of antigen-presenting cells (APC), such as dendritic cells (DC), leading to the downstream response by cytotoxic T cells and natural killer cells (NK). As ICD represents an important target to direct and develop new pharmacological interventions, the identification of bioactive natural products, which are endowed with low side effects, higher tolerability and preferentially inducing immunogenic programmed cell death, represents a priority in biomedical research. The ability of ICD to drive the immune response depends on two major factors, neither of which is intrinsic to cell death: ‘Antigenicity and adjuvanticity’. Indeed, the use of natural ICD-triggering molecules, alone or in combination with different (immuno)therapies, can result in higher efficacy and tolerability. Here, we focused on natural (marine) compounds, particularly on marine microalgae derived molecules such as exopolysaccharides, sulphated polysaccharides, glycopeptides, glycolipids, phospholipids, that are endowed with ICD-inducing properties and sulfavants. Here, we discuss novel and repurposed small-molecule ICD triggers, as well as their ability to target important molecular pathways including the IL-6, TNF-α and interferons (IFNs), leading to immune stimulation, which could be used alone or in combinatorial immunotherapeutic strategies in cancer prevention and therapies.
Modeling of Hypoxic Brain Injury through 3D Human Neural Organoids
Authors: Kim Min Soo , Kim Da-Hyun , Kang Hyun Kyoung , Kook Myung Geun , Choi Soon Won , Kang Kyung-Sun
Published: January 2021

Brain organoids have emerged as a novel model system for neural development, neurodegenerative diseases, and human-based drug screening. However, the heterogeneous nature and immature neuronal development of brain organoids generated from pluripotent stem cells pose challenges. Moreover, there are no previous reports of a three-dimensional (3D) hypoxic brain injury model generated from neural stem cells. Here, we generated self-organized 3D human neural organoids from adult dermal fibroblast-derived neural stem cells. Radial glial cells in these human neural organoids exhibited characteristics of the human cerebral cortex trend, including an inner (ventricular zone) and an outer layer (early and late cortical plate zones). These data suggest that neural organoids reflect the distinctive radial organization of the human cerebral cortex and allow for the study of neuronal proliferation and maturation. To utilize this 3D model, we subjected our neural organoids to hypoxic injury. We investigated neuronal damage and regeneration after hypoxic injury and reoxygenation. Interestingly, after hypoxic injury, reoxygenation restored neuronal cell proliferation but not neuronal maturation. This study suggests that human neural organoids generated from neural stem cells provide new opportunities for the development of drug screening platforms and personalized modeling of neurodegenerative diseases, including hypoxic brain injury.
A Multimodal Platform for Simultaneous T-cell Imaging, Defined Activation, and Mechanobiological Characterization
Authors: Fölser Martin , Motsch Viktoria , Platzer René , Huppa Johannes B. , Schütz Gerhard J.
Published: January 2021

T-cell antigen recognition is accompanied by extensive morphological rearrangements of the contact zone between the T-cell and the antigen-presenting cell (APC). This process involves binding of the T-cell receptor (TCR) complex to antigenic peptides presented via MHC on the APC surface, the interaction of costimulatory and adhesion proteins, remodeling of the actin cytoskeleton, and the initiation of downstream signaling processes such as the release of intracellular calcium. However, multiparametric time-resolved analysis of these processes is hampered by the difficulty in recording the different readout modalities at high quality in parallel. In this study, we present a platform for simultaneous quantification of TCR distribution via total internal reflection fluorescence microscopy, of intracellular calcium levels, and of T-cell-exerted forces via atomic force microscopy (AFM). In our method, AFM cantilevers were used to bring single T-cells into contact with the activating surface. We designed the platform specifically to enable the study of T-cell triggering via functionalized fluid-supported lipid bilayers, which represent a widely accepted model system to stimulate T-cells in an antigen-specific manner. In this paper, we showcase the possibilities of this platform using primary transgenic T-cells triggered specifically via their cognate antigen presented by MHCII.
A Model to Assess Eastern Cottonwood Water Flow Using Adjusted Vapor Pressure Deficit Associated with a Climate Change Impact Application
Authors: Ouyang Ying , Leininger Theodor D. , Renninger Heidi , Gardiner Emile S. , Samuelson Lisa
Published: January 2021

Short-rotation woody crops have maintained global prominence as biomass feedstocks for bioenergy, in part due to their fast growth and coppicing ability. However, the water usage efficiency of some woody biomass crops suggests potential adverse hydrological impacts. Monitoring tree water use in large-scale plantations would be very time-consuming and cost-prohibitive because it would typically require the installation and maintenance of sap flux sensors and dataloggers or other instruments. We developed a model to estimate the sap flux of eastern cottonwood (Populus deltoides. Bartr. ex Marsh.)) grown in bioenergy plantations. This model is based on adjusted vapor pressure deficit (VPD) using Structural Thinking and Experiential Learning Laboratory with Animation (STELLA) software (Architect Version 1.8.2), and is validated using the sap flux data collected from a 4-year-old eastern cottonwood biomass production plantation. With R2 values greater than 0.79 and Nash Sutcliffe coefficients greater than 0.69 and p values < 0.001, a strong agreement was obtained between measured and predicted diurnal sap flux patterns and annual sap flux cycles. We further validated the model using eastern cottonwood sap flux data from Aiken, South Carolina, USA with a good agreement between method predictions and field measurements. The model was able to predict a typical diurnal pattern, with sap flux density increasing during the day and decreasing at night for a 5-year-old cottonwood plantation. We found that a 10% increase in VPD due to climate change increased the sap flux of eastern cottonwood by about 5%. Our model also forecasted annual sap flux characteristics of measured cycles that increased in the spring, reached a maximum in the summer, and decreased in the fall. The model developed here can be adapted to estimate sap flux of other trees species in a time- and cost-effective manner.
Acknowledgment to Reviewers of Cosmetics in 2020
Authors:   Cosmetics Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Cosmetics maintains its standards for the high quality of its published papers [...]
A Switchable Cholesteric Phase Grating with a Low Operating Voltage
Authors: Sohn Ho-Jin , Oh Seung-Won , Choi Yeongyu , Ji Seong-Min , Yoon Tae-Hoon
Published: January 2021

We demonstrate a simple fabrication method of a uniform-lying-helix (ULH) cholesteric liquid crystal (ChLC) cell for phase grating device applications. To utilize a stable ULH state, we set the pitches of ChLCs as half of the cell gap to obtain the fingerprint texture with homeotropic anchoring. With the given grating period, the diffraction efficiency of the ULH cell can be maximized by optimizing the cell gap. We found that the fabricated grating device can provide a large diffraction angle of 10° and a low operating voltage of 3 V with a diffraction efficiency of 30%. We expect potential applications of the device for diffraction optics, optical interconnects, and beam steering devices.
Variation in Properties of Pre-Nucleation Calcium Carbonate Clusters Induced by Aggregation: A Molecular Dynamics Study
Authors: Wang Bing-Bing , Xiao Yi , Xu Zhi-Ming
Published: January 2021

Numerous studies have speculated calcium carbonate (CaCO3) nucleation induced by pre-nucleation clusters (PNCs) aggregation. However, it is challenging for experiments to directly obtain the relationship between PNCs aggregation and nucleation. Herein, we employ molecular dynamics simulations to explore the variation during PNCs aggregation, which can describe the beginning stage of CaCO3 nucleation induced by PNCs aggregation in supersaturated solutions. The results reveal that the formation of CaCO3 nucleus consists of PNCs spontaneous growth, PNCs solubility equilibrium, and aggregation of PNCs inducing nucleation. The PNCs aggregation, accompanied by the variation in the configuration and stability of CaCO3 aggregate, breaks the solubility equilibrium of PNCs and creates conditions for the formation of the more stable nucleus. Besides, the CaCO3 nucleus with the higher coordination number and the lower hydration number form when decreasing the CaCO3 concentration or increasing the temperature. This work not only sheds light on the formation of the CaCO3 nucleus but also contributes to the explanation for CaCO3 polymorphism.
Virtual Oncology Appointments during the Initial Wave of the COVID-19 Pandemic: An International Survey of Patient Perspectives
Authors: Loree Jonathan M. , Dau Hallie , Rebić Nevena , Howren Alyssa , Gastonguay Louise , McTaggart-Cowan Helen , Gill Sharlene , Raghav Kanwal , De Vera Mary A.
Published: January 2021

There has been rapid implementation of virtual oncology appointments in response to the COVID-19 pandemic, particularly in its first wave. Our objective was to assess patterns and perspectives towards virtual oncology appointments during the pandemic among patients with cancer undergoing active treatment. We conducted an international Internet-based cross-sectional survey. Participants were eligible if they (1) were ≥18 years of age; (2) had been diagnosed with cancer (3) were currently undergoing cancer treatment, and (4) spoke English or French. Between 23 April 2020 and 9 June 2020, 381 individuals accessed the survey, with 212 actively undergoing treatment for cancer, including 27% with colorectal, 21% with breast, 7% with prostate and 7% with lung cancer. A total of 52% of respondents were from Canada and 35% were from the United States. Many participants (129, 62%) indicated having had a virtual oncology appointment during the COVID-19 pandemic and most were satisfied with their experience (83%). We found older participants (≥50 years; adjusted OR 0.22, 95% CI 0.06 to 0.85 compared to <50 years) and those with shortest duration of treatment (≤3 months; adjusted OR 0.06; 95% CI 0 to 0.69 compared to >12 months) were less likely to be satisfied with virtual oncology appointments. Virtual health platforms used differed across countries with higher telephone use in Canada (87%) and other countries (86%) as compared to the United States (54%; p-value < 0.05), where there was higher use of video conferencing. Altogether, our findings demonstrate favorable patient perspectives towards virtual oncology appointments experienced during the first wave of the COVID-19 pandemic.
Predation and Scavenging in the City: A Review of Spatio-Temporal Trends in Research
Authors: Luna Álvaro , Romero-Vidal Pedro , Arrondo Eneko
Published: January 2021

Many researchers highlight the role of urban ecology in a rapidly urbanizing world. Despite the ecological and conservation implications relating to carnivores in cities, our general understanding of their potential role in urban food webs lacks synthesis. In this paper, we reviewed the scientific literature on urban carnivores with the aim of identifying major biases in this topic of research. In particular, we explored the number of articles dealing with predation and scavenging, and assessed the geographical distribution, biomes and habitats represented in the scientific literature, together with the richness of species reported and their traits. Our results confirmed that scavenging is largely overlooked compared to predation in urban carnivore research. Moreover, research was biased towards cities located in temperate biomes, while tropical regions were less well-represented, a pattern that was more evident in the case of articles on scavenging. The species reported in both predation and scavenging articles were mainly wild and domestic mammals with high meat-based diets and nocturnal habits, and the majority of the studies were conducted in the interior zone of cities compared to peri-urban areas. Understanding the trophic role of carnivores in urban environments and its ecological consequences will require full recognition of both their predation and scavenging facets, which is especially desirable given the urban sprawl that has been predicted in the coming decades.
No Detection of Methicillin-Resistant Staphylococcus aureus in Dairy Goats
Authors: Persson Ylva , Börjesson Stefan , Myrenås Mattias , Pedersen Karl
Published: January 2021

This short communication addresses the hypothesis that the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) is low in dairy goats in Sweden. Methicillin-resistant S. aureus is a widespread zoonotic bacterium of clinical importance in both animals and humans. In Sweden, MRSA is rare among both animals and humans. However, MRSA has been detected in a few goat herds in Sweden with a high within-herd occurrence of mecC-MRSA, but only a limited number of herds were investigated and most of them were not producing milk for human consumption. The prevalence of MRSA among dairy goat herds in Sweden is not known and a cross-sectional prevalence study was therefore conducted. A total of 22 bulk milk samples from the same number of herds, and pooled swabs from nose, mouth, and perineum from 113 goats, were collected during August and September 2019 for bacteriological investigation. After culturing on selective media, suspected isolates were confirmed as S. aureus using MALDI-TOF and subjected to PCR targeting the mecA and mecC genes to confirm MRSA status. No samples were found to be positive for MRSA, and there are therefore no indications of a spread of MRSA in Swedish dairy goat herds.
Effect of Exercise on Inflamed Psoas Muscle in Women with Obesity: A Pilot Prospective 18F-FDG PET/CT Study
Authors: Pahk Kisoo , Kim Eung Ju , Joung Chanmin , Kwon Hyun Woo , Seo Hong Seog , Kim Sungeun
Published: January 2021

Obesity increases inflammation in skeletal muscle thereby promoting systemic inflammation which leads to increased risk of cardiometabolic disease. This prospective study aimed to evaluate whether the metabolic activity of psoas muscle (PM) was associated with systemic inflammation, and whether physical exercise could reduce the PM metabolic activity evaluated by 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in women with obesity. A total of 23 women with obesity who participated in a 3-month physical exercise program were enrolled. 18F-FDG PET/CT was performed before the start of the program (baseline) and after completion of the program. The maximum standardized uptake value of psoas muscle (PM SUVmax) was used for the PM metabolic activity. The SUVmax of spleen and bone marrow, and the high-sensitivity C-reactive protein were used to evaluate the systemic inflammation. At baseline, PM SUVmax was strongly correlated with the systemic inflammation. The exercise program significantly reduced the PM SUVmax, in addition to adiposity and systemic inflammation. Furthermore, we found that the association between PM SUVmax and the systemic inflammation disappeared after completion of the exercise program. In women with obesity, PM SUVmax, assessed by 18F-FDG PET/CT, was associated with obesity-induced systemic inflammation and exercise reduced the PM SUVmax and eliminated its association with systemic inflammation.
Evaluation of Eye-Pain Severity between Dry-Eye Subtypes
Authors: Yoshikawa Yamato , Yokoi Norihiko , Kato Hiroaki , Sakai Rieko , Komuro Aoi , Sonomura Yukiko , Ikeda Tsunehiko , Sotozono Chie
Published: January 2021

The aim of this study was to assess eye pain between dry eye (DE) subtypes using questionnaires and the PainVision® (Osachi) apparatus. This study involved 52 eyes of 52 DE patients with eye pain (43 females and 9 males; mean age: 64.2 ± 13.2 (mean ± SD) years) who were classified into three DE subtypes (aqueous deficient DE (ADDE); decreased wettability DE (DWDE); and increased evaporation DE (IEDE)) based on fluorescein breakup pattern. In all subjects, severity of eye pain was evaluated using PainVision®, the DE-symptom-questionnaire visual analog scale (DSQ-VAS), and the Short-Form McGill Pain Questionnaire 2 (SF-MPQ-2). The severity of eye pain was compared between the three DE subtypes. PainVision® findings revealed greater severity of eye pain in ADDE and DWDE than in IEDE (p < 0.05, respectively), despite no difference being found in each questionnaire. A significant correlation was found between eye pain in DSQ-VAS and continuous pain, intermittent pain, neuropathic pain, and total pain in SF-MPQ-2 (R = 0.50, 0.49, 0.47, and 0.56, respectively) (all: p < 0.001). Greater severity of eye pain was found in ADDE and DWDE than in IEDE, and PainVision® was found useful for the objective assessment of eye pain.
Quantitative Evaluation of CFTR Pre-mRNA Splicing Dependent on the (TG)mTn Poly-Variant Tract
Authors: Sterrantino Manuela , Fuso Andrea , Pierandrei Silvia , Bruno Sabina Maria , Testino Giancarlo , Cimino Giuseppe , Angeloni Antonio , Lucarelli Marco
Published: January 2021

Genetic analysis in cystic fibrosis (CF) is a difficult task. Within the many causes of variability and uncertainty, a major determinant is poor knowledge of the functional effect of most DNA variants of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene. In turn, knowledge of the effect of a CFTR variant has dramatic diagnostic, prognostic and, in the era of CF precision medicine, also therapeutic consequences. One of the most challenging CFTR variants is the (TG)mTn haplotype, which has variable functional effect and controversial clinical consequences. The exact quantification of the anomalous splicing of CFTR exon 10 (in the HGVS name; exon 9 in the legacy name) and, consequently, of the residual wild-type functional CFTR mRNA, should be mandatory in clinical assessment of patients with potentially pathological haplotype of this tract. Here, we present a real time-based assay for the quantification of the proportion of exon 10+/exon 10− CFTR mRNA, starting from nasal brushing. Our assay proved rapid, economic and easy to perform. Specific primers used for this assay are either disclosed or commercially available, allowing any laboratory to easily perform it. A simplified analysis of the data is provided, facilitating the interpretation of the results. This method helps to enhance the comprehension of the genotype–phenotype relationship in CF and CFTR-related disorders (CFTR-RD), crucial for the diagnosis, prognosis and personalized therapy of CF.
Biosynthesized Silica Nanosuspension as Thermal Fluid in Parabolic Solar Panels
Authors: Corzo-Deluquez Enrique , Pineda-Muñoz Lina , Ruíz-Chamorro Adiela , Ocampo-López Carlos , Ramírez-Carmona Margarita , Rendón-Castrillón Leidy
Published: January 2021

In this work, the production of biologically synthesized silica nanoparticles was proposed to prepare a nanosuspension as a thermal fluid in parabolic solar panels at the laboratory level. Silica nanoparticles were produced from construction sand in two stages. Biosynthesis broth was produced by Aspergillus niger aerated fermentation in a 1 L bioreactor for 9 days. Each supernatant was contacted with 18% construction sand in a 500 L reactor with mechanical agitation, at a temperature of 25 °C, and a contact time of 30 min. Subsequently, the separation process was carried out. For day 9, a pH value of 1.71 was obtained as well as acid concentrations of 15.78 g/L for citrus and 4.16 g/L for malic. The metal extraction efficiency of Si nanoparticles was 19%. The vibration peaks in the FTIR were characteristic of the presence of silica nanoparticles in wavenumbers 1020 cm−1 and 1150 cm−1. Finally, a prototype solar radiation test bench for parabolic systems was built and provided with a radiation source that falls on a translucent pipe that transports the nanoparticles, which has a pump and a series of thermocouples. The heat capacity of the biotechnologically produced silica nanoparticle suspension was 0.72 ± 0.05 kJ/kgK, using material and energy balances in the flow circuit.
Physical Literacy and Teacher Training: Pilot Study
Authors: Hernaiz-Sánchez Ariadna , Villaverde-Caramés Eloy José , González-Valeiro Miguel , Fernández-Villarino Maria A.
Published: January 2021

With the appearance of physical literacy, a new approach to physical education has emerged, aimed at promoting lifelong physical activity. With the intention of exploring whether physical education teacher training programmes are in line with this trend, we analysed the conceptions of pre-service teachers. The aim of this study was to design and validate a questionnaire analysing the conceptions of students taking the degree course in the Science of Physical Activity and Sport with regard to what it means to be a physically well-educated student. A questionnaire was designed for data collection. A chi-square test was used to analyse the statistically significant differences and Cramer’s V was used to quantify the degree of association. The results show that pre-service teachers consider a physically well-educated student to be one who maintains a healthy lifestyle and has overall motor competence and self-awareness. Differences have been found between the conceptions of pre-service teachers, between universities and between the beginning and the end of training programs. A valid and reliable instrument has been obtained for analysing the conceptions of pre-service teachers. The studies reinforce the conceptions related to an active lifestyle and overall motor competence. The conceptions of pre-service teachers are within closer range of physical literacy after their studies.
Challenges of Active Learning in a View of Integrated Engineering Education
Authors: Vodovozov Valery , Raud Zoja , Petlenkov Eduard
Published: January 2021

The fourth industrial revolution has triggered a notable shift in engineering education, bringing the need to create new professionals. In this context, the active learning approach appears to be more important than ever. Nevertheless, to date quite lot of challenges related to active learning have been accumulated. Diversity of backgrounds and knowledge levels of students presented together in the same learning environment can become a source of dissatisfaction and failure for several groups of learners. To explore the reasons for these phenomena, the conduct of different categories of learners is examined and compared in terms of individual engagement and success in education. It is found that the student-centered approach is not necessarily the best method of teaching and learning when applied to students with great differentiation. A number of other conditions are required for success, namely, working in small groups, drawing on learner’s abilities, individual instruction methods, etc. These conditions are analyzed in detail in this study. The need for a rigorous and systematic orientation of learners in a multidimensional educational environment is proposed as a prospective form and an integral part of the university staff activity.
Enabling Large-Scale Simulations of Quantum Transport with Manycore Computing
Authors: Jeong Yosang , Ryu Hoon
Published: January 2021

The non-equilibrium Green’s function (NEGF) is being utilized in the field of nanoscience to predict transport behaviors of electronic devices. This work explores how much performance improvement can be driven for quantum transport simulations with the aid of manycore computing, where the core numerical operation involves a recursive process of matrix multiplication. Major techniques adopted for performance enhancement are data restructuring, matrix tiling, thread scheduling, and offload computing, and we present technical details on how they are applied to optimize the performance of simulations in computing hardware, including Intel Xeon Phi Knights Landing (KNL) systems and NVIDIA general purpose graphic processing unit (GPU) devices. With a target structure of a silicon nanowire that consists of 100,000 atoms and is described with an atomistic tight-binding model, the effects of optimization techniques on the performance of simulations are rigorously tested in a KNL node equipped with two Quadro GV100 GPU devices, and we observe that computation is accelerated by a factor of up to ∼20 against the unoptimized case. The feasibility of handling large-scale workloads in a huge computing environment is also examined with nanowire simulations in a wide energy range, where good scalability is procured up to 2048 KNL nodes.
Sensorless Control of Bearingless Permanent Magnet Synchronous Motor Based on LS-SVM Inverse System
Authors: Hua Yizhou , Zhu Huangqiu
Published: January 2021

In order to solve the problems of low integration, low reliability, and high cost caused by mechanical sensors used in bearingless permanent magnet synchronous motor (BPMSM) control systems, a novel speed and displacement sensorless control method using a least-squares support vector machine (LS-SVM) left inverse system is proposed in this paper. Firstly, the suspension force generation principle of the BPMSM is introduced, and the mathematical model of the BPMSM is derived. Secondly, the observation principle of the left inverse system is explained, and the left reversibility of the established speed and displacement subsystem is proved. Thirdly, the left inverse systems of the speed and displacement subsystems are constructed by using the LS-SVM, and the complete speed and displacement sensorless control system is constructed. Finally, the simulations and experiments of the proposed method are performed. The research results demonstrate that the proposed observation method can identify the speed and displacement quickly and accurately, and the sensorless control method can realize the stable operation of the BPMSM without speed and displacement sensors.
Battery Charger Based on a Resonant Converter for High-Power LiFePO4 Batteries
Authors: Brañas Christian , Viera Juan C. , Azcondo Francisco J. , Casanueva Rosario , Gonzalez Manuela , Díaz Francisco J.
Published: January 2021

A new battery charger, based on a multiphase resonant converter, for a high-capacity 48 V LiFePO4 lithium-ion battery is presented. LiFePO4 batteries are among the most widely used today and offer high energy efficiency, high safety performance, very good temperature behavior, and a long cycle life. An accurate control of the charging current is necessary to preserve the battery health. The design of the charger is presented in a tight correlation with a battery model based on experimental data obtained at the laboratory. With the aim of reducing conduction losses, the general analysis of the inverter stage obtained from the parallel connection of N class D LCpCs resonant inverters is carried out. The study provides criteria for proper selection of the transistors and diodes as well as the value of the DC-link voltage. The effect of the leakage inductance of the transformer on the resonant circuit is also evaluated, and a design solution to cancel it is proposed. The output stage is based on a multi-winding current-doubler rectifier. The converter is designed to operate in open-loop operation as an input voltage-dependent current source, but in closed-loop operation, it behaves as a voltage source with an inherent maximum output current limitation, which provides high reliability throughout the whole charging process. The curve of efficiency of the proposed charger exhibits a wide flat zone that includes light load conditions.
Terahertz Technologies and Its Applications
Authors: Pacheco-Peña Victor
Published: January 2021

The terahertz frequency range (0 [...]
Reinforced Transformer with Cross-Lingual Distillation for Cross-Lingual Aspect Sentiment Classification
Authors: Wu Hanqian , Wang Zhike , Qing Feng , Li Shoushan
Published: January 2021

Though great progress has been made in the Aspect-Based Sentiment Analysis(ABSA) task through research, most of the previous work focuses on English-based ABSA problems, and there are few efforts on other languages mainly due to the lack of training data. In this paper, we propose an approach for performing a Cross-Lingual Aspect Sentiment Classification (CLASC) task which leverages the rich resources in one language (source language) for aspect sentiment classification in a under-resourced language (target language). Specifically, we first build a bilingual lexicon for domain-specific training data to translate the aspect category annotated in the source-language corpus and then translate sentences from the source language to the target language via Machine Translation (MT) tools. However, most MT systems are general-purpose, it non-avoidably introduces translation ambiguities which would degrade the performance of CLASC. In this context, we propose a novel approach called Reinforced Transformer with Cross-Lingual Distillation (RTCLD) combined with target-sensitive adversarial learning to minimize the undesirable effects of translation ambiguities in sentence translation. We conduct experiments on different language combinations, treating English as the source language and Chinese, Russian, and Spanish as target languages. The experimental results show that our proposed approach outperforms the state-of-the-art methods on different target languages.
A New Approach for Power Losses Evaluation of IGBT/Diode Module
Authors: Hafezi Hossein , Faranda Roberto
Published: January 2021

Electric power systems are facing tremendous changes and power electronic devices are playing an increasingly crucial role in this transformation. In this contest, the study of power electronic devices behavior becomes of the utmost importance, and in particular, evaluation of their losses to understand their performance. Several methods can be found in literature to evaluate power or energy losses, but each of them is associated with shortcomings (such as missing an important factor or having narrow current or voltage range) that in practice become a strong limit to implement them or in a simulation process. To overcome this problem, this paper evaluates existing methods and proposes new loss calculation methods for power electronics losses that can be used within simulation tools at any converter configuration and application range, splitting power electronic losses into switching and conduction losses. The proposed new approach formulates each loss calculation procedure in a systematic way. The presented methods are implemented in Matlab Simulink and simulation results are compared with data obtained from the Semikron SemiSel v4 online tool, which is used as a benchmark. The outcomes reveal that, with this new approach, the proposed methods can cover wider working operation range compared to the existing methods having better accuracy.
An Advanced Machine Learning Based Energy Management of Renewable Microgrids Considering Hybrid Electric Vehicles’ Charging Demand
Authors: Lan Tianze , Jermsittiparsert Kittisak , T. Alrashood Sara , Rezaei Mostafa , Al-Ghussain Loiy , A. Mohamed Mohamed
Published: January 2021

Renewable microgrids are new solutions for enhanced security, improved reliability and boosted power quality and operation in power systems. By deploying different sources of renewables such as solar panels and wind units, renewable microgrids can enhance reducing the greenhouse gasses and improve the efficiency. This paper proposes a machine learning based approach for energy management in renewable microgrids considering a reconfigurable structure based on remote switching of tie and sectionalizing. The suggested method considers the advanced support vector machine for modeling and estimating the charging demand of hybrid electric vehicles (HEVs). In order to mitigate the charging effects of HEVs on the system, two different scenarios are deployed; one coordinated and the other one intelligent charging. Due to the complex structure of the problem formulation, a new modified optimization method based on dragonfly is suggested. Moreover, a self-adaptive modification is suggested, which helps the solutions pick the modification method that best fits their situation. Simulation results on an IEEE microgrid test system show its appropriate and efficient quality in both scenarios. According to the prediction results for the total charging demand of the HEVs, the mean absolute percentage error is 0.978, which is very low. Moreover, the results show a 2.5% reduction in the total operation cost of the microgrid in the intelligent charging compared to the coordinated scheme.
A Review on Management of End of Life Tires (ELTs) and Alternative Uses of Textile Fibers
Authors: Grammelis Panagiotis , Margaritis Nikolaos , Dallas Petros , Rakopoulos Dimitrios , Mavrias Georgios
Published: January 2021

Annually, approximately 3 billion tires are commercially transacted worldwide each year and an equivalent amount is disposed of by the end of their life. Despite the increase in the life of tires and the global economic and pandemic crisis, the number of discarded tires is going to rise further due to the increasing demand for vehicles worldwide (approximately 5 billion tires by the end of 2030). The obsolete methods of tire disposal, including landfill, burning, etc., are a responsible for environmental issues (harmful substances production, air and soil pollution) and for the transmission of various diseases. Nowadays, approximately 70% of the total tires at the end of their life (ELTs) is recovered. The largest percentage of the recovered ELTs is intended for energy production or recovery as a fuel in cement industries or can be used for the production of various materials. A significant amount (approximately 95%) of the discarded ELTs can be reused. The products from the processing of ELTs can be fragments of different sizes and types, including: Trimmed rubber (70% by weight), steel wire (5–30% by weight), and fluff or textile fibers (up to 15% by weight). From the aforementioned materials, rubber and steel wires are mainly recovered and used for numerous applications. However, current ways of utilizing these materials will have to adapt or change in the near future, in order to comply with stricter regulations. The purpose of the current study is to sufficiently review recent progress on the management of ELTs, focusing on alternative uses of textile fibers such as additive for sound absorbing materials, bituminous conglomerates, concrete production, plastic materials, soil reinforcement, etc.
Profit-Based Unit Commitment for a GENCO Equipped with Compressed Air Energy Storage and Concentrating Solar Power Units
Authors: Nasouri Gilvaei Mostafa , Hosseini Imani Mahmood , Jabbari Ghadi Mojtaba , Li Li , Golrang Anahita
Published: January 2021

With the advent of restructuring in the power industry, the conventional unit commitment problem in power systems, involving the minimization of operation costs in a traditional vertically integrated system structure, has been transformed to the profit-based unit commitment (PBUC) approach, whereby generation companies (GENCOs) perform scheduling of the available production units with the aim of profit maximization. Generally, a GENCO solves the PBUC problem for participation in the day-ahead market (DAM) through determining the commitment and scheduling of fossil-fuel-based units to maximize their own profit according to a set of forecasted price and load data. This study presents a methodology to achieve optimal offering curves for a price-taker GENCO owning compressed air energy storage (CAES) and concentrating solar power (CSP) units, in addition to conventional thermal power plants. Various technical and physical constraints regarding the generation units are considered in the provided model. The proposed framework is mathematically described as a mixed-integer linear programming (MILP) problem, which is solved by using commercial software packages. Meanwhile, several cases are analyzed to evaluate the impacts of CAES and CSP units on the optimal solution of the PBUC problem. The achieved results demonstrate that incorporating the CAES and CSP units into the self-scheduling problem faced by the GENCO would increase its profitability in the DAM to a great extent.
Experimental Study of Single Taylor Bubble Rising in Stagnant and Downward Flowing Non-Newtonian Fluids in Inclined Pipes
Authors: Liu Yaxin , Upchurch Eric R. , Ozbayoglu Evren M.
Published: January 2021

An experimental investigation of single Taylor bubbles rising in stagnant and downward flowing non-Newtonian fluids was carried out in an 80 ft long inclined pipe (4°, 15°, 30°, 45° from vertical) of 6 in. inner diameter. Water and four concentrations of bentonite–water mixtures were applied as the liquid phase, with Reynolds numbers in the range 118 < Re < 105,227 in countercurrent flow conditions. The velocity and length of Taylor bubbles were determined by differential pressure measurements. The experimental results indicate that for all fluids tested, the bubble velocity increases as the inclination angle increases, and decreases as liquid viscosity increases. The length of Taylor bubbles decreases as the downward flow liquid velocity and viscosity increase. The bubble velocity was found to be independent of the bubble length. A new drift velocity correlation that incorporates inclination angle and apparent viscosity was developed, which is applicable for non-Newtonian fluids with the Eötvös numbers (E0) ranging from 3212 to 3405 and apparent viscosity (μapp) ranging from 0.001 Pa∙s to 129 Pa∙s. The proposed correlation exhibits good performance for predicting drift velocity from both the present study (mean absolute relative difference is 0.0702) and a database of previous investigator’s results (mean absolute relative difference is 0.09614).
Analytical Models of Axially Loaded Blind Rivets Used with Sandwich Beams
Authors: Studziński Robert
Published: January 2021

The paper presents the novel use of analytical models of a beam on an elastic foundation. The one-parameter model (Winkler model) and the two-parameter models (Filonenko-Borodich and Pasternak models) were investigated. These models were used to describe the elastic response of axially loaded blind rivets used with sandwich structures. The elastic response related to the elastic strain energy is mentioned in the paper as the resilience modulus of the connection. The databases from laboratory pull-out tests were used to verify these models. One type of blind rivet (aluminum, with three clamping arms) and one type of sandwich beam were used. The sandwich beams used in the experiments consisted of two thin-walled and stiff external facings (zinc-coated steel) and a thick, soft core (polyisocyanurate foam—PIR). In the test the sandwich beams were subjected to static, axial pull-out loading. The research provides the quantitative comparison between the laboratory experiment and the analytical solutions from models adopted for this type of connection. Additionally, the failure mechanisms, the secant stiffness at the ultimate capacity, and the strain energy capacity of the elastic foundation at failure are considered. To the author’s knowledge, this approach has not been described in the literature so far.
Thermal Efficiency of Trombe Wall in the South Facade of a Frame Building
Authors: Miąsik Przemysław , Krasoń Joanna
Published: January 2021

The article presents the possibility of using a mass collector-storage wall (CSW), integrated into the structure of a building with a light skeleton structure. The considered system is a proposal for an energy-saving solution that can be used in buildings with various utility purposes. The article presents the results of experimental tests of a collector-storage wall mounted in the space of the skeleton structure of the southern facade of a building for the period of one year, as well as the results of numerical simulation. In the summer, the influence of the use of heat-insulating roller shutters on limiting overheating of the chamber interior was investigated. The effect of using the roller shutters is a reduction in the average value of the heat flux by about 77%. In the winter, the energy efficiency of the wall was tested. The obtained effect is energy consumption during the heating season at a level comparable to a wall with a traditional structure with a coefficient of U = 0.30 W/(m2K). The results of the numerical tests showed high agreement with the direct results, which provides a basis for the use of such simulations in further research on the search for the optimal structure of a collector-storage wall.