bluuebunny/crossref_metadata_2025 huggingface dataset:
Translating Videos into Synthetic Training Data for Wearable Sensor-Based Activity Recognition Systems Using Residual Deep Convolutional Networks
Authors: Fortes Rey Vitor , Garewal Kamalveer Kaur , Lukowicz Paul
Published: March 2021

Human activity recognition (HAR) using wearable sensors has benefited much less from recent advances in Deep Learning than fields such as computer vision and natural language processing. This is, to a large extent, due to the lack of large scale (as compared to computer vision) repositories of labeled training data for sensor-based HAR tasks. Thus, for example, ImageNet has images for around 100,000 categories (based on WordNet) with on average 1000 images per category (therefore up to 100,000,000 samples). The Kinetics-700 video activity data set has 650,000 video clips covering 700 different human activities (in total over 1800 h). By contrast, the total length of all sensor-based HAR data sets in the popular UCI machine learning repository is less than 63 h, with around 38 of those consisting of simple mode of locomotion activities like walking, standing or cycling. In our research we aim to facilitate the use of online videos, which exist in ample quantities for most activities and are much easier to label than sensor data, to simulate labeled wearable motion sensor data. In previous work we already demonstrated some preliminary results in this direction, focusing on very simple, activity specific simulation models and a single sensor modality (acceleration norm). In this paper, we show how we can train a regression model on generic motions for both accelerometer and gyro signals and then apply it to videos of the target activities to generate synthetic Inertial Measurement Units (IMU) data (acceleration and gyro norms) that can be used to train and/or improve HAR models. We demonstrate that systems trained on simulated data generated by our regression model can come to within around 10% of the mean F1 score of a system trained on real sensor data. Furthermore, we show that by either including a small amount of real sensor data for model calibration or simply leveraging the fact that (in general) we can easily generate much more simulated data from video than we can collect its real version, the advantage of the latter can eventually be equalized.
Estimating Thermal Material Properties Using Solar Loading Lock-in Thermography
Authors: Klein Samuel , Fernandes Henrique , Herrmann Hans-Georg
Published: March 2021

This work investigates the application of lock-in thermography approach for solar loading thermography applications. In conventional lock-in thermography, a specimen is subjected to a periodically changing heat flux. This heat flux usually enters the specimen in one of three ways: by a point source, a line source or an extended source (area source). Calculations based on area sources are particularly well suited to adapt to solar loading thermography, because most natural heat sources and heat sinks can be approximated to be homogenously extended over a certain region of interest. This is of particular interest because natural heat phenomena cover a large area, which makes this method suitable for measuring large-scale samples. This work investigates how the extended source approximation formulas for determining thermally thick and thermally thin material properties can be used in a naturally excited setup, shows possible error sources, and gives quantitative results for estimating thermal effusivity of a retaining wall structure. It shows that this method can be used on large-scale structures that are subject to natural outside heating phenomena.
Incorporation of Potential Fields and Motion Primitives for the Collision Avoidance of Unmanned Aircraft
Authors: Lee Kyuman , Choi Daegyun , Kim Donghoon
Published: March 2021

Collision avoidance (CA) using the artificial potential field (APF) usually faces several known issues such as local minima and dynamically infeasible problems, so unmanned aerial vehicles’ (UAVs) paths planned based on the APF are safe only in a certain environment. This research proposes a CA approach that combines the APF and motion primitives (MPs) to tackle the known problems associated with the APF. Since MPs solve for a locally optimal trajectory with respect to allocated time, the trajectory obtained by the MPs is verified as dynamically feasible. When a collision checker based on the k-d tree search algorithm detects collision risk on extracted sample points from the planned trajectory, generating re-planned path candidates to avoid obstacles is performed. After rejecting unsafe route candidates, one applies the APF to select the best route among the remaining safe-path candidates. To validate the proposed approach, we simulated two meaningful scenario cases—the presence of static obstacles situation with local minima and dynamic environments with multiple UAVs present. The simulation results show that the proposed approach provides smooth, efficient, and dynamically feasible pathing compared to the APF.
Effects of Coal Mining Height and Width on Overburden Subsidence in Longwall Pier-Column Backfilling
Authors: Wang Xiaozhen , Xie Jianlin , Xu Jialin , Zhu Weibing , Wang Limin
Published: March 2021

Longwall pier-column backfilling is a partial backfilling technique initially designed in thin coal seam mines. With the increase of mining intensity, the mining height and width of the backfilling working face will also increase. It is necessary to analyze how changes in working face dimensions influence the control effect of overburden subsidence in pier-column backfilling. In this study, a mining model with a combination of 25 conditions (five different mining heights (1~3 m) × five different mining widths (80~240 m)) was designed using a FLAC3D (Vision 5.0) numerical simulation. The simulation was used to analyze the control effect of overburden subsidence with varying mining heights and widths. In addition, according to the field working face conditions, two physical similarity models were performed to explore the overburden subsidence law in pier-column backfilling with different mining heights and widths. It was observed from the above study that mining heights and widths will have a different influence on the overburden subsidence in longwall pier-column backfilling. The result of this study provides strong theoretical support for evaluating the control effect of overburden subsidence in longwall pier-column backfilling.
Towards an Occupancy-Oriented Digital Twin for Facility Management: Test Campaign and Sensors Assessment
Authors: Seghezzi Elena , Locatelli Mirko , Pellegrini Laura , Pattini Giulia , Di Giuda Giuseppe Martino , Tagliabue Lavinia Chiara , Boella Guido
Published: March 2021

This study focuses on calibration and test campaigns of an IoT camera-based sensor system to monitor occupancy, as part of an ongoing research project aiming at defining a Building Management System (BMS) for facility management based on an occupancy-oriented Digital Twin (DT). The research project aims to facilitate the optimization of building operational stage through advanced monitoring techniques and data analytics. The quality of collected data, which are the input for analyses and simulations on the DT virtual entity, is critical to ensure the quality of the results. Therefore, calibration and test campaigns are essential to ensure data quality and efficiency of the IoT sensor system. The paper describes the general methodology for the BMS definition, and method and results of first stages of the research. The preliminary analyses included Indicative Post-Occupancy Evaluations (POEs) supported by Building Information Modelling (BIM) to optimize sensor system planning. Test campaign are then performed to evaluate collected data quality and system efficiency. The method was applied on a Department of Politecnico di Milano. The period of the year in which tests are performed was critical for lighting conditions. In addition, spaces’ geometric features and user behavior caused major issues and faults in the system.Incorrect boundary definition: areas that are not covered by boundaries; thus, they are not monitored
Refining Citrus Wastes: From Discarded Oranges to Efficient Brewing Biocatalyst, Aromatic Beer, and Alternative Yeast Extract Production
Authors: Ganatsios Vassilios , Terpou Antonia , Bekatorou Argyro , Plessas Stavros , Koutinas Athanasios A.
Published: March 2021

Agro-industrial wastes can be valorized as biorefinery raw materials through innovative, environmentally friendly bioprocessing for added value products. In this study, a process for citrus waste valorization within the biorefinery concept is proposed, including the development of an effective biocatalyst, based on immobilized cells, for aromatic beer production, and an alternative yeast extract (AYE) production in the same unit. Specifically, orange pulp from discarded oranges was applied as an immobilization carrier of the alcohol-resistant and cryotolerant yeast strain S. cerevisiae AXAZ-1. The yeast culture was produced by minor nutrient supplementation using diluted molasses as substrate. An effective Citrus Waste Brewing Biocatalyst (CWBB) was produced and applied for beer fermentation. The aroma-related compounds in beer produced with free yeast cells or the CWBB were evaluated by solid-phase micro-extraction (SPME) gas chromatography–mass spectrometry (GC–MS). The analysis showed that the beers produced by the CWBB had a more complex volatile profile compared with beer fermented by the free cells. More specifically, the CWBB enhanced the formation of esters and terpenes by 5- and 27-fold, respectively. In the frame of the proposed multiprocessing biorefinery concept, the spent CWBB, after it has completed its cycle of brewing batches, was used as substrate for AYE production through autolysis. The produced AYE significantly affected the yeast growth when compared to commercial yeast extract (CYE). More specifically, it promoted the biomass productivity and biomass yield factor by 60–150% and 110–170%, respectively. Thus, AYE could be successfully used for industrial cell growth as an efficient and cheaper substitute of CYE. Within a circular economy framework, the present study highlights the potential use of citrus waste to produce aromatic beer combined with AYE production as an alternative way to valorize these wastes.
Allosteric Kinase Inhibitors Reshape MEK1 Kinase Activity Conformations in Cells and In Silico
Authors: Fleischmann Jakob , Feichtner Andreas , DeFalco Louis , Kugler Valentina , Schwaighofer Selina , Huber Roland G , Stefan Eduard
Published: March 2021

Mutations at different stages of the mitogen-activated protein kinase (MAPK) signaling pathway lead to aberrant activation of the involved protein kinase entities. These oncogenic modifications alter signal propagation which converge on the gatekeeper kinases MEK1/2, transmitting the input signal to ERK1/2. Thus, targeted MEK inhibition causes qualitative alterations of carcinogenic MAPK signals. Phosphorylation of the MEK1 activation loop at the positions S218 and S222 by RAF kinases triggers the conformational alignment of MEK’s catalytic pocket to enable ATP-binding and substrate phosphorylation. We have extended a kinase conformation (KinCon) biosensor platform to record MEK1 activity dynamics. In addition to MEK phosphorylation by BRAF, the integration of the phosphorylation-mimetic mutations S218D/S222D triggered opening of the kinase. Structural rearrangement may involve the flexibility of the N terminal MEK1 A-helix. Application of the allosterically acting MEK inhibitors (MEKi) trametinib, cobimentinib, refametinib, and selumetinib converted activated MEK1 KinCon reporters back into a more closed inactive conformation. We confirmed MEK1 KinCon activity dynamics upon drug engagement using the patient-derived melanoma cell line A2058, which harbors the V600E hotspot BRAF mutation. In order to confirm biosensor dynamics, we simulated structure dynamics of MEK1 kinase in the presence and absence of mutations and/or MEKi binding. We observed increased dynamics for the S218D/S222D double mutant particularly in the region of the distal A-helix and alpha-C helix. These data underline that MEK1 KinCon biosensors have the potential to be subjected to MEKi efficacy validations in an intact cell setting.
The Mitochondrial Carnitine Acyl-carnitine Carrier (SLC25A20): Molecular Mechanisms of Transport, Role in Redox Sensing and Interaction with Drugs
Authors: Tonazzi Annamaria , Giangregorio Nicola , Console Lara , Palmieri Ferdinando , Indiveri Cesare
Published: March 2021

The SLC25A20 transporter, also known as carnitine acyl-carnitine carrier (CAC), catalyzes the transport of short, medium and long carbon chain acyl-carnitines across the mitochondrial inner membrane in exchange for carnitine. The 30-year story of the protein responsible for this function started with its purification from rat liver mitochondria. Even though its 3D structure is not yet available, CAC is one of the most deeply characterized transport proteins of the inner mitochondrial membrane. Other than functional, kinetic and mechanistic data, post-translational modifications regulating the transport activity of CAC have been revealed. CAC interactions with drugs or xenobiotics relevant to human health and toxicology and the response of the carrier function to dietary compounds have been discovered. Exploiting combined approaches of site-directed mutagenesis with chemical targeting and bioinformatics, a large set of data on structure/function relationships have been obtained, giving novel information on the molecular mechanism of the transport catalyzed by this protein.
Targeting Pin1 for Modulation of Cell Motility and Cancer Therapy
Authors: Chuang Hsiang-Hao , Zhen Yen-Yi , Tsai Yu-Chen , Chuang Cheng-Hao , Huang Ming-Shyan , Hsiao Michael , Yang Chih-Jen
Published: March 2021

Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) specifically binds and isomerizes the phosphorylated serine/threonine-proline (pSer/Thr-Pro) motif, which leads to changes in protein conformation and function. Pin1 is widely overexpressed in cancers and plays an important role in tumorigenesis. Mounting evidence has revealed that targeting Pin1 is a potential therapeutic approach for various cancers by inhibiting cell proliferation, reducing metastasis, and maintaining genome stability. In this review, we summarize the underlying mechanisms of Pin1-mediated upregulation of oncogenes and downregulation of tumor suppressors in cancer development. Furthermore, we also discuss the multiple roles of Pin1 in cancer hallmarks and examine Pin1 as a desirable pharmaceutical target for cancer therapy. We also summarize the recent progress of Pin1-targeted small-molecule compounds for anticancer activity.
Probing Skin Barrier Recovery on Molecular Level Following Acute Wounds: An In Vivo/Ex Vivo Study on Pigs
Authors: Mojumdar Enamul Haque , Madsen Lone Bruhn , Hansson Henri , Taavoniku Ida , Kristensen Klaus , Persson Christina , Morén Anna Karin , Mokso Rajmund , Schmidtchen Artur , Ruzgas Tautgirdas , Engblom Johan
Published: March 2021

Proper skin barrier function is paramount for our survival, and, suffering injury, there is an acute need to restore the lost barrier and prevent development of a chronic wound. We hypothesize that rapid wound closure is more important than immediate perfection of the barrier, whereas specific treatment may facilitate perfection. The aim of the current project was therefore to evaluate the quality of restored tissue down to the molecular level. We used Göttingen minipigs with a multi-technique approach correlating wound healing progression in vivo over three weeks, monitored by classical methods (e.g., histology, trans-epidermal water loss (TEWL), pH) and subsequent physicochemical characterization of barrier recovery (i.e., small and wide-angle X-ray diffraction (SWAXD), polarization transfer solid-state NMR (PTssNMR), dynamic vapor sorption (DVS), Fourier transform infrared (FTIR)), providing a unique insight into molecular aspects of healing. We conclude that although acute wounds sealed within two weeks as expected, molecular investigation of stratum corneum (SC) revealed a poorly developed keratin organization and deviations in lipid lamellae formation. A higher lipid fluidity was also observed in regenerated tissue. This may have been due to incomplete lipid conversion during barrier recovery as glycosphingolipids, normally not present in SC, were indicated by infrared FTIR spectroscopy. Evidently, a molecular approach to skin barrier recovery could be a valuable tool in future development of products targeting wound healing.
The Role of Metabolism in Tumor Immune Evasion: Novel Approaches to Improve Immunotherapy
Authors: Cruz-Bermúdez Alberto , Laza-Briviesca Raquel , Casarrubios Marta , Sierra-Rodero Belén , Provencio Mariano
Published: March 2021

The tumor microenvironment exhibits altered metabolic properties as a consequence of the needs of tumor cells, the natural selection of the most adapted clones, and the selfish relationship with other cell types. Beyond its role in supporting uncontrolled tumor growth, through energy and building materials obtention, metabolism is a key element controlling tumor immune evasion. Immunotherapy has revolutionized the treatment of cancer, being the first line of treatment for multiple types of malignancies. However, many patients either do not benefit from immunotherapy or eventually relapse. In this review we overview the immunoediting process with a focus on the metabolism-related elements that are responsible for increased immune evasion, either through reduced immunogenicity or increased resistance of tumor cells to the apoptotic action of immune cells. Finally, we describe the main molecules to modulate these immune evasion processes through the control of the metabolic microenvironment as well as their clinical developmental status.
Probing the Rhipicephalus bursa Sialomes in Potential Anti-Tick Vaccine Candidates: A Reverse Vaccinology Approach
Authors: Couto Joana , Seixas Gonçalo , Stutzer Christian , Olivier Nicholas A. , Maritz-Olivier Christine , Antunes Sandra , Domingos Ana
Published: March 2021

In the wake of the ‘omics’ explosion of data, reverse vaccinology approaches are being applied more readily as an alternative for the discovery of candidates for next generation diagnostics and vaccines. Promising protective antigens for the control of ticks and tick-borne diseases can be discovered by mining available omics data for immunogenic epitopes. The present study aims to explore the previously obtained Rhipicephalus bursa sialotranscriptome during both feeding and Babesia infection, to select antigenic targets that are either membrane-associated or a secreted protein, as well as unique to the ectoparasite and not present in the mammalian host. Further, they should be capable of stimulating T and B cells for a potential robust immune response, and be non-allergenic or toxic to the host. From the R. bursa transcriptome, 5706 and 3025 proteins were identified as belonging to the surfaceome and secretome, respectively. Following a reverse genetics immunoinformatics pipeline, nine preferred candidates, consisting of one transmembrane-related and eight secreted proteins, were identified. These candidates showed a higher predicted antigenicity than the Bm86 antigen, with no homology to mammalian hosts and exposed regions. Only four were functionally annotated and selected for further in silico analysis, which examined their protein structure, surface accessibility, flexibility, hydrophobicity, and putative linear B and T-cell epitopes. Regions with overlapping coincident epitopes groups (CEGs) were evaluated to select peptides that were further analyzed for their physicochemical characteristics, potential allergenicity, toxicity, solubility, and potential propensity for crystallization. Following these procedures, a set of three peptides from the three R. bursa proteins were selected. In silico results indicate that the designed epitopes could stimulate a protective and long-lasting immune response against those tick proteins, reflecting its potential as anti-tick vaccines. The immunogenicity of these peptides was evaluated in a pilot immunization study followed by tick feeding to evaluate its impact on tick behavior and pathogen transmission. Combining in silico methods with in vivo immunogenicity evaluation enabled the screening of vaccine candidates prior to expensive infestation studies on the definitive ovine host animals.
Introduction of Mouse Embryonic Fibroblasts into Early Embryos Causes Reprogramming and (Con)fusion
Authors: Savatier Pierre
Published: March 2021

The reprogramming of somatic cell nuclei to achieve pluripotency is one of the most important biological discoveries of the last few decades [...]
Vegetation and Glacier Trends in the Area of the Maritime Alps Natural Park (Italy): MaxEnt Application to Predict Habitat Development
Authors: Comino Elena , Fiorucci Adriano , Rosso Maurizio , Terenziani Andrea , Treves Anna
Published: March 2021

Climate change is significantly affecting ecosystem services and leading to strong impacts on the extent and distribution of glaciers and vegetation. In this context, species distribution models represent a suitable instrument for studying ecosystem development and response to climate warming. This study applies the maximum entropy model, MaxEnt, to evaluate trends and effects of climate change for three environmental indicators in the area of the Alpi Marittime Natural Park under the Municipality of Entracque (Italy). Specifically, this study focuses on the magnitude of the retreat of six glaciers and on the distribution of two different plant communities, Alnus viridis scrub and Fagus sylvatica forest associated with Acer pseudoplatanus and tall herbs (megaforbie), in relation to predicted increases in mean temperatures. MaxEnt software was used to model and observe changes over a thirty-year period, developing three scenarios: a present (2019), a past (1980) and a future (2050) using 24 “environmental layers”. This study showed the delicate climate balances of these six small glaciers that, in the next 30 years, are likely to undergo an important retreat (≈−33%) despite the high altitude and important snowfall that still characterize the area. At the same time, it is predicted that the two plant communities will invade those higher altitude territories that, not so long ago, were inhospitable, expanding their habitat by 50%. The MaxEnt application to glaciers has shown to be an effective tool that offers a new perspective in the climate change field as well as in biodiversity conservation planning.
Diamonds from the Mir Pipe (Yakutia): Spectroscopic Features and Annealing Studies
Authors: Rakhmanova Mariana I. , Komarovskikh Andrey Yu. , Palyanov Yuri N. , Kalinin Alexander A. , Yuryeva Olga P. , Nadolinny Vladimir A.
Published: March 2021

For this study, 21 samples of colorless octahedral diamonds (weighing 5.4–55.0 mg) from the Mir pipe (Yakutia) were investigated with photoluminescence (PL), infrared (IR), and electron paramagnetic resonance (EPR) spectroscopies. Based on the IR data, three groups of diamonds belonging to types IIa, IaAB, and IaB were selected and their spectroscopic features were analyzed in detail. The three categories of stones exhibited different characteristic PL systems. The type IaB diamonds demonstrated dominating nitrogen–nickel complexes S2, S3, and 523 nm, while they were less intensive or even absent in the type IaAB crystals. The type IIa diamonds showed a double peak at 417.4 + 418.7 nm (the 418 center in this study), which is assumed to be a nickel–boron defect. In the crystals analyzed, no matter which type, 490.7, 563.5, 613, and 676.3 nm systems of various intensity could be detected; moreover, N3, H3, and H4 centers were very common. The step-by-step annealing experiments were performed in the temperature range of 600–1700 °C. The treatment at 600 °C resulted in the 563.5 nm system’s disappearance; the interstitial carbon vacancy annihilation could be considered as a reason. The 676.5 nm and 613 nm defects annealed out at 1500 °C and 1700 °C, respectively. Furthermore, as a result of annealing at 1500 °C, the 558.5 and 576 nm centers characteristic of superdeep diamonds from São Luis (Brazil) appeared. These transformations could be explained by nitrogen diffusion or interaction with the dislocations and/or vacancies produced.
Consensus Recommendations for MRD Testing in Adult B-Cell Acute Lymphoblastic Leukemia in Ontario
Authors: Tierens Anne , Stockley Tracy L. , Campbell Clinton , Fulcher Jill , Leber Brian , McCready Elizabeth , Sabatini Peter J. B. , Sadikovic Bekim , Schuh Andre C.
Published: March 2021

Measurable (minimal) residual disease (MRD) is an established, key prognostic factor in adult B-cell acute lymphoblastic leukemia (B-ALL), and testing for MRD is known to be an important tool to help guide treatment decisions. The clinical value of MRD testing depends on the accuracy and reliability of results. Currently, there are no Canadian provincial or national guidelines for MRD testing in adult B-ALL, and consistent with the absence of such guidelines, there is no uniform Ontario MRD testing consensus. Moreover, there is great variability in Ontario in MRD testing with respect to where, when, and by which technique, MRD testing is performed, as well as in how the results are interpreted. To address these deficiencies, an expert multidisciplinary working group was convened to define consensus recommendations for improving the provision of such testing. The expert panel recommends that MRD testing should be implemented in a centralized manner to ensure expertise and accuracy in testing for this low volume indication, thereby to provide accurate, reliable results to clinicians and patients. All adult patients with B-ALL should receive MRD testing after induction chemotherapy. Philadelphia chromosome (Ph)-positive patients should have ongoing monitoring of MRD during treatment and thereafter, while samples from Ph-negative B-ALL patients should be tested at least once later during treatment, ideally at 12 to 16 weeks after treatment initiation. In Ph-negative adult B-ALL patients, standardized, ideally centralized, protocols must be used for MRD testing, including both flow cytometry and immunoglobulin (Ig) heavy chain and T-cell receptor (TCR) gene rearrangement analysis. For Ph-positive B-ALL patients, MRD testing using a standardized protocol for reverse transcription real-time quantitative PCR (RT-qPCR) for the BCR-ABL1 gene fusion transcript is recommended, with Ig/TCR gene rearrangement analysis done in parallel likely providing additional clinical information.
Cardiac Resynchronization Therapy in Non-Ischemic Cardiomyopathy: Role of Multimodality Imaging
Authors: Stătescu Cristian , Ureche Carina , Enachi Ștefana , Radu Rodica , Sascău Radu A.
Published: March 2021

Non-ischemic cardiomyopathy encompasses a heterogeneous group of diseases, with a generally unfavorable long-term prognosis. Cardiac resynchronization therapy (CRT) is a useful therapeutic option for patients with symptomatic heart failure, currently recommended by all available guidelines, with outstanding benefits, especially in non-ischemic dilated cardiomyopathy. Still, in spite of clear indications based on identifying a dyssynchronous pattern on the electrocardiogram (ECG,) a great proportion of patients are non-responders. The idea that multimodality cardiac imaging can play a role in refining the selection criteria and the implant technique and help with subsequent system optimization is promising. In this regard, predictors of CRT response, such as apical rocking and septal flash have been identified. Promising new data come from studies using cardiac magnetic resonance and nuclear imaging for showcasing myocardial dyssynchrony. Still, to date, no single imaging predictor has been included in the guidelines, probably due to lack of validation in large, multicenter cohorts. This review provides an up-to-date synthesis of the latest evidence of CRT use in non-ischemic cardiomyopathy and highlights the potential additional value of multimodality imaging for improving CRT response in this population. By incorporating all these findings into our clinical practice, we can aim toward obtaining a higher proportion of responders and improve the success rate of CRT.
Statistical Analysis of the Relationship between AETA Electromagnetic Anomalies and Local Earthquakes
Authors: Guo Qinmeng , Yong Shanshan , Wang Xin’an
Published: March 2021

To verify the relationship between AETA (Acoustic and Electromagnetics to Artificial Intelligence (AI)) electromagnetic anomalies and local earthquakes, we have performed statistical studies on the electromagnetic data observed at AETA station. To ensure the accuracy of statistical results, 20 AETA stations with few data missing and abundant local earthquake events were selected as research objects. A modified PCA method was used to obtain the sequence representing the signal anomaly. Statistical results of superposed epoch analysis have indicated that 80% of AETA stations have significant relationship between electromagnetic anomalies and local earthquakes. These anomalies are more likely to appear before the earthquakes rather than after them. Further, we used Molchan’s error diagram to evaluate the electromagnetic signal anomalies at stations with significant relationships. All area skill scores are greater than 0. The above results have indicated that AETA electromagnetic anomalies contain precursory information and have the potential to improve local earthquake forecasting.
Research on the Prediction of A-Share “High Stock Dividend” Phenomenon—A Feature Adaptive Improved Multi-Layers Ensemble Model
Authors: Fu Yi , Li Bingwen , Zhao Jinshi , Bi Qianwen
Published: March 2021

Since the “high stock dividend” of A-share companies in China often leads to the short-term stock price increase, this phenomenon’s prediction has been widely concerned by academia and industry. In this study, a new multi-layer stacking ensemble algorithm is proposed. Unlike the classic stacking ensemble algorithm that focused on the differentiation of base models, this paper used the equal weight comprehensive feature evaluation method to select features before predicting the base model and used a genetic algorithm to match the optimal feature subset for each base model. After the base model’s output prediction, the LightGBM (LGB) model was added to the algorithm as a secondary information extraction layer. Finally, the algorithm inputs the extracted information into the Logistic Regression (LR) model to complete the prediction of the “high stock dividend” phenomenon. Using the A-share market data from 2010 to 2019 for simulation and evaluation, the proposed model improves the AUC (Area Under Curve) and F1 score by 0.173 and 0.303, respectively, compared to the baseline model. The prediction results shed light on event-driven investment strategies.
Solution-Processed Organic and ZnO Field-Effect Transistors in Complementary Circuits
Authors: Barron John , Pickett Alec , Glaser James , Guha Suchismita
Published: March 2021

The use of high κ dielectrics lowers the operating voltage in organic field-effect transistors (FETs). Polymer ferroelectrics open the path not just for high κ values but allow processing of the dielectric films via electrical poling. Poled ferroelectric dielectrics in p-type organic FETs was seen to improve carrier mobility and reduce leakage current when compared to unpoled devices using the same dielectric. For n-type FETs, solution-processed ZnO films provide a viable low-cost option. UV–ozone-treated ZnO films was seen to improve the FET performance due to the filling of oxygen vacancies. P-type FETs were fabricated using the ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) as the dielectric along with a donor–acceptor polymer based on diketopyrrolopyrrole (DPP-DTT) as the semiconductor layer. The DPP-DTT FETs yield carrier mobilities upwards of 0.4 cm2/Vs and high on/off ratios when the PVDF-TrFE layer is electrically poled. For n-type FETs, UV–ozone-treated sol–gel ZnO films on SiO2 yield carrier mobilities of 10−2 cm2/Vs. DPP-DTT-based p- and ZnO-based n-type FETs were used in a complementary voltage inverter circuit, showing promising characteristic gain. A basic inverter model was used to simulate the inverter characteristics, using parameters from the individual FET characteristics.
Defective Product Classification System for Smart Factory Based on Deep Learning
Authors: Nguyen Huy Toan , Yu Gwang-Huyn , Shin Nu-Ri , Kwon Gyeong-Ju , Kwak Woo-Young , Kim Jin-Young
Published: March 2021

Smart factories merge various technologies in a manufacturing environment in order to improve factory performance and product quality. In recent years, these smart factories have received a lot of attention from researchers. In this paper, we introduce a defective product classification system based on deep learning for application in smart factories. The key component of the proposed system is a programmable logic controller (PLC) artificial intelligence (AI) embedded board; we call this an AI Edge-PLC module. A pre-trained defective product classification model is uploaded to a cloud service from where the AI Edge-PLC can access and download it for use on a certain product, in this case, electrical wiring. Next, we setup the system to collect electrical wiring data in a real-world factory environment. Then, we applied preprocessing to the collected data in order to extract a region of interest (ROI) from the images. Due to limitations on the availability of appropriate labeled data, we used the transfer learning method to re-train a classification model for our purposes. The pre-trained models were then optimized for applications on AI Edge-PLC boards. After carrying out classification tasks, on our electrical wire dataset and on a previously published casting dataset, using various deep neural networks including VGGNet, ResNet, DenseNet, and GoogLeNet, we analyzed the results achieved by our system. The experimental results show that our system is able to classify defective products quickly with high accuracy in a real-world manufacturing environment.
Ten-Bit 0.909-MHz 8-Channel Dual-Mode Successive Approximation ADC for a BLDC Motor Drive
Authors: Huang Chong-Cheng , Sung Guo-Ming , Xiao Xiong , Sung Shan-Hao , Huang Chao-Hung
Published: March 2021

This paper presents a 10-bit 0.909-MHz 8-channel dual-mode successive approximation (SAR) analogue-to-digital converter (ADC) for brushless direct current (BLDC) motor drive, using a Taiwan Semiconductor Manufacturing (TSMC) 0.25 μm 1P3M Complementary Metal Oxide Semiconductor (CMOS) process. The sample-and-hold (S/H) circuit operates with two sampling modes. One is individually sampling eight channels in sequence with an S/H circuit and the other is sampling four channels simultaneously with four S/H circuits. All sampled data will be digitized with high-speed SAR ADC in time division multiplexing (TDM). A dynamic latch-type comparator is utilized to latch the output at an upper or lower level. The advantage of the designed comparator is that it performs with positive feedback to quickly complete the latch function. The double-tail latch-type architecture is utilized to mitigate the significant kickback effect by separating the pre-amplifier stage from the latch. By integrating an input NMOSFET with an input PMOSFET, the designed latch-type comparator can perform with full-swing input voltage. Measurements show that the signal-to-noise ratio (SNR), signal-to-noise-and-distortion ratio (SNDR), effective number of bits (ENOB), power consumption, and chip area are 50.56 dB, 57.03 dB, 8.11 bits, 833 μW, and 1.35 × 0.98 mm2, respectively. The main advantages of the proposed multichannel dual-mode SAR ADC are its low power consumption of 833 μW and high measured resolution of 8.11 bits.
On the Sampling of the Fresnel Field Intensity over a Full Angular Sector
Authors: Pierri Rocco , Moretta Raffaele
Published: March 2021

In this article, the question of how to sample the square amplitude of the radiated field in the framework of phaseless antenna diagnostics is addressed. In particular, the goal of the article is to find a discretization scheme that exploits a non-redundant number of samples and returns a discrete model whose mathematical properties are similar to those of the continuous one. To this end, at first, the lifting technique is used to obtain a linear representation of the square amplitude of the radiated field. Later, a discretization scheme based on the Shannon sampling theorem is exploited to discretize the continuous model. More in detail, the kernel of the related eigenvalue problem is first recast as the Fourier transform of a window function, and after, it is evaluated. Finally, the sampling theory approach is applied to obtain a discrete model whose singular values approximate all the relevant singular values of the continuous linear model. The study refers to a strip source whose square magnitude of the radiated field is observed in the Fresnel zone over a 2D observation domain.
The Influence of Opencast Lignite Mining Dehydration on Plant Production—A Methodological Study
Authors: Pepliński Benedykt , Czubak Wawrzyniec
Published: March 2021

In many circles, brown coal continues to be viewed as a cheap source of energy, resulting in numerous investments in new opencast brown coal mines. Such a perception of brown coal energy is only possible if the external costs associated with mining and burning coal are not considered. In past studies, external cost analysis has focused on the external costs of coal burning and associated emissions. This paper focuses on the extraction phase and assesses the external costs to agriculture associated with the resulting depression cone. This paper discusses the difficulties researchers face in estimating agricultural losses resulting from the development of a depression cone due to opencast mineral extraction. In the case of brown coal, the impacts are of a geological, natural-climatic, agricultural-productive, temporal, and spatial nature and result from a multiplicity of interacting factors. Then, a methodology for counting external costs in crop production was proposed. The next section estimates the external costs of crop production arising from the operation of opencast mines in the Konin-Turek brown coal field, which is located in central Poland. The analyses conducted showed a large decrease in grain and potato yields and no effect of the depression cone on sugar beet levels. Including the estimated external costs in the cost of producing electricity from mined brown coal would significantly worsen the profitability of that production.
Stability Analysis of Different Regulation Modes of Hydropower Units
Authors: Guo Xinran , Cheng Yuanchu , Wei Jiada , Luo Yitian
Published: March 2021

The dynamic characteristics of hydropower unit governing systems considerably influence the stability of hydropower units and the connected power system. The dynamic performances of hydropower units with power regulation mode (PRM) and opening regulation mode (ORM) are different. This paper establishes a detailed linear model of a hydropower unit based on the Phillips–Heffron model. The damping characteristic and stability of two regulation modes with different water inertia time constants TW were analyzed. ORM tended to provide negative damping, while PRM often provided positive damping in the major parts of the frequency range within the normal frequency oscillations when TW was large. Eigenvalue analysis illustrated that PRM has better stability than ORM. To validate the analysis, a simulation under two typical faults WAS conducted based on a nonlinear model of a hydropower unit. The simulation results illustrated that the responses of units with PRM are more stable in terms of important operating parameters, such as output power, rotor speed, and power angles. For hydropower units facing challenges in stable operation, PRM is recommended to obtain good dynamic stability.
Big and Young Supermassive Black Holes in the Early Universe
Authors: Sbarrato Tullia
Published: March 2021

Blazars are active galactic nuclei characterized by relativistic jets launched in the vicinity of the central engine (i.e., a supermassive black hole), which are oriented close to our line of sight. Their peculiar orientation makes them very efficient tracers of the overall jetted population, and due to their brightness they can be visible up to very high redshifts. A deep knowledge of these objects can provide fundamental clues to the models of formation and growth of the first supermassive black holes, but the search for them in the early Universe must be careful and follow a systematic approach. The discovery in the last ∼15 years of extremely massive blazars at very high redshifts (MBH>109M⊙, z>4) revolutionized our perception of their earliest evolution: there seem to be different formation epochs for extremely massive black holes hosted in jetted (z∼4) and non-jetted (z∼2.5) systems. This is not easy to explain, since one would expect jetted sources to accrete less efficiently. Small differences in the population are also derived from the search for such high-z sources. We will go through the open questions in order to understand where the common knowledge stands and which steps must be taken to better understand the formation and common evolution of supermassive black holes and jets in the early Universe.
History of Astronomy in Australia: Big-Impact Astronomy from World War II until the Lunar Landing (1945–1969)
Authors: Graham Alister , Kenyon Katherine , Bull Lochlan , Lokuge Don Visura , Kuhlmann Kazuki
Published: March 2021

Radio astronomy commenced in earnest after World War II, with Australia keenly engaged through the Council for Scientific and Industrial Research. At this juncture, Australia’s Commonwealth Solar Observatory expanded its portfolio from primarily studying solar phenomena to conducting stellar and extragalactic research. Subsequently, in the 1950s and 1960s, astronomy gradually became taught and researched in Australian universities. However, most scientific publications from this era of growth and discovery have no country of affiliation in their header information, making it hard to find the Australian astronomy articles from this period. In 2014, we used the then-new Astrophysics Data System (ADS) tool Bumblebee to overcome this challenge and track down the Australian-led astronomy papers published during the quarter of a century after World War II, from 1945 until the lunar landing in 1969. This required knowledge of the research centres and facilities operating at the time, which are briefly summarised herein. Based on citation counts—an objective, universally-used measure of scientific impact—we report on the Australian astronomy articles which had the biggest impact. We have identified the top-ten most-cited papers, and thus also their area of research, from five consecutive time-intervals across that blossoming quarter-century of astronomy. Moreover, we have invested a substantial amount of time researching and providing a small tribute to each of the 62 scientists involved, including several trail-blazing women. Furthermore, we provide an extensive list of references and point out many interesting historical connections and anecdotes.
Pseudo-Starvation Driven Energy Expenditure Negatively Affects Ovarian Follicle Development
Authors: Meng Li , Coleman Verena , Zhao Yu , Ost Mario , Voigt Anja , Bunschoten Annelies , Keijer Jaap , Teerds Katja , Klaus Susanne
Published: March 2021

In the present investigation, we examined whether a change in whole body energy fluxes could affect ovarian follicular development, employing mice ectopically expressing uncoupling protein 1 in skeletal muscle (UCP1-TG). Female UCP1-TG and wild-type (WT) mice were dissected at the age of 12 weeks. Energy intake and expenditure, activity, body weight and length, and body composition were measured. Plasma insulin, glucose, leptin, plasma fibroblast growth factor 21 (FGF21) and plasma insulin-like growth factor 1 (IGF1) levels were analyzed and ovarian follicle and corpus luteum numbers were counted. IGF1 signaling was analyzed by immunohistochemical staining for the activation of insulin receptor substrate 1/2 (IRS1/2) and AKT. UCP1-TG female mice had increased energy expenditure, reduced body size, maintained adiposity, and decreased IGF1 concentrations compared to their WT littermates, while preantral and antral follicle numbers were reduced by 40% and 60%, respectively. Corpora lutea were absent in 40% of the ovaries of UCP1-TG mice. Phospho-IRS1, phospho-AKT -Ser473 and -Thr308 immunostaining was present in the granulosa cells of antral follicles in WT ovaries, but faint to absent in the antral follicles of UCP1-TG mice. In conclusion, the reduction in circulating IGF1 levels due to the ectopic expression of UCP1 is associated with reduced immunostaining of the IRS1-PI3/AKT pathway, which may negatively affect ovarian follicle development and ovulation.
The Effects of Spirulina Supplementation on Redox Status and Performance Following a Muscle Damaging Protocol
Authors: Pappas Aggelos , Tsiokanos Athanasios , Fatouros Ioannis , Poulios Athanasios , Kouretas Dimitris , Goutzourelas Nikos , Giakas Giannis , Jamurtas Athanasios
Published: March 2021

Spirulina plantensis is a popular supplement which has been shown to have antioxidant and performance enhancing properties. The purpose of this study was to evaluate the effects of spirulina supplementation on (a) redox status (b) muscle performance and (c) muscle damage following an eccentric bout of exercise that would induce muscle damage. Twenty-four healthy, recreationally trained males participated in the study and were randomly separated into two groups: a spirulina supplementation (6 g per day) and a placebo group. Both groups performed an eccentric bout of exercise consisting of 5 sets and 15 maximum reps per set. Blood was collected at 24, 48, 72 and 96 h after the bout and total antioxidant capacity (TAC) and protein carbonyls (PC) were assessed in plasma. Delayed onset muscle soreness (DOMS) was also assessed at the same aforementioned time points. Eccentric peak torque (EPT) was evaluated immediately after exercise, as well as at 24, 48, 72 and 96 h post exercise. Redox status indices (TAC and PC) did not change significantly at any time point post exercise. DOMS increased significantly 24 h post exercise and remained elevated until 72 h and 96 h post exercise for the placebo and spirulina group, respectively. EPT decreased significantly and immediately post exercise and remained significantly lower compared to baseline until 72 h post exercise. No significant differences between groups were found for DOMS and EPT. These results indicate that spirulina supplementation following a muscle damaging protocol does not confer beneficial effects on redox status, muscle performance or damage.