bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid Layers of Donor-Acceptor Copolymers with Homogenous Silver Nanoparticle Coverage for Photonic Applications
Authors: Cimrová Věra , Eom Sangwon , Pokorná Veronika , Kang Youngjong , Výprachtický Drahomír
Published: January 2021

Hybrid layers of donor-acceptor (D-A) copolymers containing N,N′-dialkylperylene-3,4,9,10-tetracarboxydiimide electron-acceptor units covered with silver nanoparticles (Ag-NPs) were prepared by electrochemical doping of pristine layers during reduction processes. In situ optical absorption spectra of the layers were recorded during the formation of Ag-NP coverage. The hybrid layers were characterized by absorption spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray spectroscopy (EDX). In the absorption spectra of the hybrid layers, a surface plasmon band characteristic of Ag-NPs appeared. Significant improvements in light absorption due to the plasmonic effects of Ag NPs were observed. Stable Ag-NPs with an average diameter of 41–63 nm were formed on the surface, as proven by SEM and XPS. The Ag-NP coverage and size depended on the hybrid layer preparation conditions and on the copolymer composition. The metallic character of the Ag-NPs was proven by XPS. The location in the surface layer was further confirmed by EDX analysis. To the best of our knowledge, this is the first report on such hybrid layers having the potential for a variety of photonic and electronic applications.
Improved Glucose Recovery from Sicyos angulatus by NaOH Pretreatment and Application to Bioethanol Production
Authors: An Hyung-Eun , Lee Kang Hyun , Jang Ye Won , Kim Chang-Bae , Yoo Hah Young
Published: January 2021

As greenhouse gases and environmental pollution become serious, the demand for alternative energy such as bioethanol has rapidly increased, and a large supply of biomass is required for bioenergy production. Lignocellulosic biomass is the most abundant on the planet and a large part of it, the second-generation biomass, has the advantage of not being a food resource. In this study, Sicyos angulatus, known as an invasive plant (harmful) species, was used as a raw material for bioethanol production. In order to improve enzymatic hydrolysis, S. angulatus was pretreated with different NaOH concentration at 121 °C for 10 min. The optimal NaOH concentration for the pretreatment was determined to be 2% (w/w), and the glucan content (GC) and enzymatic digestibility (ED) were 46.7% and 55.3%, respectively. Through NaOH pretreatment, the GC and ED of S. angulatus were improved by 2.4-fold and 2.5-fold, respectively, compared to the control (untreated S. angulatus). The hydrolysates from S. angulatus were applied to a medium for bioethanol fermentation of Saccharomyces cerevisiae K35. Finally, the maximum ethanol production was found to be 41.3 g based on 1000 g S. angulatus, which was 2.4-fold improved than the control group.
Enhanced Anti-Fouling Behavior and Performance of PES Membrane by UV Treatment
Authors: Russo Francesca , Bulzomì Maria , Di Nicolò Emanuele , Ursino Claudia , Figoli Alberto
Published: January 2021

An easy method to prepare hydrophilic PES membranes with anti-fouling properties was developed by UV-polymerization of poly vinyl pirrolidone (PVP) on membrane surfaces. The modified membrane surfaces were analyzed by ATR-FTIR, and the new hydrophilic nature of the membranes was determined by contact angle measurements. The novel membranes were prepared using Rhodiasolv® Polarclean as a green solvent and compared with a control PES membrane, without the exposure at the hydrophilization procedure. The influences of the UV lamp distance (15 and 30 cm) and the exposure time (0 cm to 60 cm) were evaluated. All membranes were characterized in terms of surface morphology, porosity, pore size, and pure water permeability (PWP). The treated membranes resulted in an increase in hydrophilicity and in improved performances in terms of PWP and foulant rejection. In particular, an anti-fouling test was performed using a solution of 100 mg/L of humic acid (HA) as a model foulant. The UV-treated membrane efficiency, compared with a commercial PES membrane, showed a recovery of about 97%, confirming that these membranes can be applied in wastewater treatment.
Analysis of the Heat Balance of a Metal Hydride Separator Used for the Separation of Hydrogen from Syngas
Authors: Brestovič Tomáš , Lázár Marián , Jasminská Natália , Živčák Jozef , Tóth Lukáš , Dobáková Romana , Duda Filip , Kmeťová Ľubomíra , Bednárová Ľubomíra
Published: January 2021

The present article discusses the potential for hydrogen separation using a metal hydride separator, which facilitates the generation of hydrogen contained in syngas following the thermal recovery of wastes. The article provides a detailed description of the separator heat balance using analytical calculations and optimised calculations, and by applying numerical methods. The proposed concept of a separator intended for hydrogen separation from syngas offers a solution to a problem associated with the use of metal hydride alloy powders; in particular, their low thermal conductivity. In order to eliminate big temperature differences in the alloy, a heat transfer intensifier was implemented in the metal hydride alloy volume; the intensifier was made of metal and exhibited high thermal conductivity. For the purpose of comparing the thermal fields, the first stage comprised the creation of a numerical simulation of hydrogen absorption without the use of an intensifier. Subsequently, three different geometries were created for an intensifier intended to remove heat from the metal hydride alloy powder towards the separator cover, and the effects of these three geometries were analysed. The implementation of heat transfer intensifiers into the metal hydride alloy powder improved the heat removal by as much as 43.9% and increased the thermal field homogeneity by 77%. A result of the heat removal optimisation was an increase in the hydrogen absorption kinetics and the efficiency of the separator operation.
Carbonaceous Adsorbents Derived from Agricultural Sources for the Removal of Pramipexole Pharmaceutical Model Compound from Synthetic Aqueous Solutions
Authors: Liakos Efstathios V. , Rekos Kyriazis , Giannakoudakis Dimitrios A. , Mitropoulos Athanasios C. , Kyzas George Z.
Published: January 2021

The aim of the present study was to synthesize various samples of activated carbon (AC) from different agricultural sources as precursors, like orange peels, tea stalks, and kiwi peels, as well as sucrose. The synthesis of AC was achieved with chemical activation using H3PO4 and KOH. The produced AC samples were tested as adsorbents for the removal of a pharmaceutical model compound, pramipexole dihydrochloride (PRM), from synthetic aqueous synthetic solutions. The produced-from-sucrose AC presented the higher yield of synthesis (~58%). The physicochemical features of the materials were analyzed by FTIR spectroscopy, N2 physisorption, and SEM imaging. More specifically, the AC sample derived from sucrose (SG-AC) had the highest specific surface area (1977 m2/g) with the total pores volume, mesopores volume, and external surface area being 1.382 cm3/g, 0.819 cm3/g, and 751 m2/g, respectively. The effect of the initial pH and PRM concentration were studied, while the equilibrium results (isotherms) were fitted to Langmuir and Freundlich models. The maximum adsorption capacities were found to be 213, 190, 155, and 115 mg/g for AC samples produced from sucrose, kiwi peels, orange peels, and tea stalks, respectively.
Integration of Gasification and Solid Oxide Fuel Cells (SOFCs) for Combined Heat and Power (CHP)
Authors: Costa Paula , Pinto Filomena , André Rui Neto , Marques Paula
Published: January 2021

This paper reviews the most recent information about the main operations to produce energy from carbonaceous materials, namely biomass and wastes through the integration of gasification, syngas cleaning and solid oxide fuel cells (SOFCs), which have shown to be a good option for combined heat and power (CHP) production, due to high efficiency and low environmental impact. However, some challenges still need to be overcome, mainly when mixed feedstocks with high contents of hazardous contaminants are used, thus syngas cleaning and conditioning is of major importance. Another drawback is SOFC operation, hence new materials especially for the anode has been proposed and tested. An overall process to produce CHP by gasification integration with SOFC is proposed.
Influence of Metal Oxides and Their Precursors on the Composition of Final Products of Aquathermolysis of Raw Ashalchin Oil
Authors: Petrov Sergey M. , Safiulina Aliya G. , Bashkirtseva Natalya Yu. , Lakhova Alfiya I. , Islamova Galiya G.
Published: January 2021

Experiments were conducted simulating hydrothermal conversion of heavy oil in the presence of carbonate, kaolin, Al2O3, Ni2+ and Cu2+, NiO mixed with poly-α-olefins, C6H8O7, C2H4O2 at 290–375 °C and 10–135 bar. Al2O3, carbonate at 375 °C and 135 bar, accelerated the resin degradation. Experiments with carbonate at 350 °C and 10 bar showed no significant composition changes. NiSO4, CuSO4, kaolin mineral, at 350 °C and 78 bar, accelerated decomposition of resins (from 35.6% to 32.5%). Al2O3 and carbonate at 290 °C and 14 bar led to the destruction of asphaltenes (from 6.5% to 4.7% by weight), which were adsorbed on the surface of carbonate. Al2O3, NiO, poly-α-olefins at 350 °C and 78 bar accelerated C–C bond cracking of high-boiling asphaltenes. C6H8O7, rock-forming carbonate, at 360 °C and 14 bar, contributed to the polymerization and polycondensation of hydrocarbons with the formation of additional resins. C2H4O2 and kaolin at 360 °C and 12 bar affected the reduction in the resin content from 35.6% to 31.9% wt. C2H4O2 interacted with the active metals with the formation of acetate salts exhibiting catalytic activity.
Matching Optimization of a Mixed Flow Pump Impeller and Diffuser Based on the Inverse Design Method
Authors: Wang Mengcheng , Li Yanjun , Yuan Jianping , Osman Fareed Konadu
Published: January 2021

When considering the interaction between the impeller and diffuser, it is necessary to provide logical and systematic guidance for their matching optimization. In this study, the goal was to develop a comprehensive matching optimization strategy to optimize the impeller and diffuser of a mixed flow pump. Some useful tools and methods, such as the inverse design method, computational fluid dynamics (CFD), design of experiment, surrogate model, and optimization algorithm, were used. The matching optimization process was divided into two steps. In the first step, only the impeller was optimized. Thereafter, CFD analysis was performed on the optimized impeller to get the circulation and flow field distribution at the outlet of the impeller. In the second step of optimization, the flow field and circulation distribution at the inlet of the diffuser were set to be the same as the optimized impeller outlet. The results show that the matching optimization strategy proposed in this study is effective and can overcome the shortcomings of single-component optimization, thereby further improving the overall optimization effect. Compared with the baseline model, the pump efficiency of the optimized model at 1.2Qdes, 1.0Qdes, and 0.8Qdes is increased by 6.47%, 3.68%, and 0.82%, respectively.
Commercial Thermal Technologies for Desalination of Water from Renewable Energies: A State of the Art Review
Authors: Feria-Díaz Jhon , López-Méndez María , Rodríguez-Miranda Juan , Sandoval-Herazo Luis , Correa-Mahecha Felipe
Published: January 2021

Thermal desalination is yet a reliable technology in the treatment of brackish water and seawater; however, its demanding high energy requirements have lagged it compared to other non-thermal technologies such as reverse osmosis. This review provides an outline of the development and trends of the three most commercially used thermal or phase change technologies worldwide: Multi Effect Distillation (MED), Multi Stage Flash (MSF), and Vapor Compression Distillation (VCD). First, state of water stress suffered by regions with little fresh water availability and existing desalination technologies that could become an alternative solution are shown. The most recent studies published for each commercial thermal technology are presented, focusing on optimizing the desalination process, improving efficiencies, and reducing energy demands. Then, an overview of the use of renewable energy and its potential for integration into both commercial and non-commercial desalination systems is shown. Finally, research trends and their orientation towards hybridization of technologies and use of renewable energies as a relevant alternative to the current problems of brackish water desalination are discussed. This reflective and updated review will help researchers to have a detailed state of the art of the subject and to have a starting point for their research, since current advances and trends on thermal desalination are shown.
Protonation Dynamics in the K-Channel of Cytochrome c Oxidase Estimated from Molecular Dynamics Simulations
Authors: Stegmaier Vincent , Gorriz Rene F. , Imhof Petra
Published: January 2021

Proton transfer reactions are one of the most fundamental processes in biochemistry. We present a simplistic approach for estimating proton transfer probabilities in a membrane protein, cytochrome c oxidase. We combine short molecular dynamics simulations at discrete protonation states with a Monte Carlo approach to exchange between those states. Requesting for a proton transfer the existence of a hydrogen-bonded connection between the two source and target residues of the exchange, restricts the acceptance of transfers to only those in which a proton-relay is possible. Together with an analysis of the hydrogen-bonded connectivity in one of the proton-conducting channels of cytochrome c oxidase, this approach gives insight into the protonation dynamics of the hydrogen-bonded networks. The connectivity and directionality of the networks are coupled to the conformation of an important protein residue in the channel, K362, rendering proton transfer in the entire channel feasible in only one of the two major conformations. Proton transport in the channel can thus be regulated by K362 not only through its possible role as a proton carrier itself, but also by allowing or preventing proton transport via water residues.
Acknowledgment to Reviewers of Prosthesis in 2020
Authors:   Prosthesis Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Prosthesis maintains its standards for the high quality of its published papers [...]
Insights into Mycobacterium leprae Proteomics and Biomarkers—An Overview
Authors: Gautam Sakshi , Sharma Devesh , Goel Anjana , Patil Shripad A. , Bisht Deepa
Published: January 2021

Although leprosy is curable, the identification of biomarkers for the early diagnosis of leprosy would play a pivotal role in reducing transmission and the overall prevalence of the disease. Leprosy-specific biomarkers for diagnosis, particularly for the paucibacillary disease, are not well defined. Therefore, the identification of new biomarkers for leprosy is one of the prime themes of leprosy research. Studying Mycobacterium leprae, the causative agent of leprosy, at the proteomic level may facilitate the identification, quantification, and characterization of proteins that could be potential diagnostics or targets for drugs and can help in better understanding the pathogenesis. This review aims to shed light on the knowledge gained to understand leprosy or its pathogen employing proteomics and its role in diagnosis.
The Tyrian King in MT and LXX Ezekiel 28:12b–15
Authors: Lee Lydia
Published: January 2021

The biblical prophecy in Ezekiel 28:11–19 records a dirge against the king from Tyre. While the Hebrew Masoretic Text (MT) identifies the monarch as a cherub, the Greek Septuagint (LXX) distinguishes the royal from the cherub. Scholarly debates arise as to which edition represents the more original version of the prophecy. This article aims to contribute to the debates by adopting a text-critical approach to the two variant literary editions of the dirge, comparing and analyzing their differences, while incorporating insights gleaned from the extra-biblical literature originating from the ancient Near East, Second Temple Period, and Late Antiquity. The study reaches the conclusion that the current MT, with its presentation of a fluid boundary between the mortal and divine, likely builds on a more ancient interpretation of the Tyrian king. On the other hand, while the Hebrew Vorlage of LXX Ezekiel 28:12b–15 resembles the Hebrew text of the MT, the Greek translator modifies the text via literary allusions and syntactical rearrangement, so that the final result represents a later reception that suppresses any hints at the divinity of the Tyrian ruler. The result will contribute to our understanding of the historical development of the ancient Israelite religion.
Digital Apostleship: Evangelization in the New Agora
Authors: Galang Justine Renus F. , Macaraan Willard Enrique R.
Published: January 2021

The digital space is understood not as a parallel and antithetical component of one’s lived existentiality but a significant and substantial component of human existence that if ethically considered can be a platform for realizing religious identity, mission, and vocation. In this paper, social media platforms are argued as the new digital agoras that reflect the dynamics of the ancient Greek agoras. The nexus of interaction between the social media as the new agora and the Christian vocation and mission of evangelization and apostleship is the point of realized commitment among Christians to take part in the formation of a culture of synodality through an empowered and engaged presence in social media. Divided into two parts, the paper tackles social media platforms as the new agoras of the contemporary world and delves into a theological exploration of the digital apostleship in the new agoras with particular stress on the universality of the vocation and its potential contribution toward realizing the vision of a synodal Church.
Erratum: Liang, X., et al. Applying Deep Learning to Clear-Sky Radiance Simulation for VIIRS with Community Radiative Transfer Model—Part 2: Model Architecture and Assessment. Remote Sens. 2020, 12, 3825
Authors: Liang Xingming , Liu Quanhua (Mark)
Published: January 2021

The authors would like to make the following correction of [...]
Correction: Zhang, G., et al. Shadow Detection and Restoration for Hyperspectral Images Based on Nonlinear Spectral Unmixing. Remote Sensing 2020, 12, 3985
Authors: Zhang Guichen , Cerra Daniele , Müller Rupert
Published: January 2021

The authors would like to make the following correction of [...]
Characterising Termite Mounds in a Tropical Savanna with UAV Laser Scanning
Authors: D’hont Barbara , Calders Kim , Bartholomeus Harm , Whiteside Tim , Bartolo Renee , Levick Shaun , Krishna Moorthy Sruthi M. , Terryn Louise , Verbeeck Hans
Published: January 2021

Termite mounds are found over vast areas in northern Australia, delivering essential ecosystem services, such as enhancing nutrient cycling and promoting biodiversity. Currently, the detection of termite mounds over large areas requires airborne laser scanning (ALS) or high-resolution satellite data, which lack precise information on termite mound shape and size. For detailed structural measurements, we generally rely on time-consuming field assessments that can only cover a limited area. In this study, we explore if unmanned aerial vehicle (UAV)-based observations can serve as a precise and scalable tool for termite mound detection and morphological characterisation. We collected a unique data set of terrestrial laser scanning (TLS) and UAV laser scanning (UAV-LS) point clouds of a woodland savanna site in Litchfield National Park (Australia). We developed an algorithm that uses several empirical parameters for the semi-automated detection of termite mounds from UAV-LS and used the TLS data set (1 ha) for benchmarking. We detected 81% and 72% of the termite mounds in the high resolution (1800 points m−2) and low resolution (680 points m−2) UAV-LS data, respectively, resulting in an average detection of eight mounds per hectare. Additionally, we successfully extracted information about mound height and volume from the UAV-LS data. The high resolution data set resulted in more accurate estimates; however, there is a trade-off between area and detectability when choosing the required resolution for termite mound detection Our results indicate that UAV-LS data can be rapidly acquired and used to monitor and map termite mounds over relatively large areas with higher spatial detail compared to airborne and spaceborne remote sensing.
Evaluation of Penman-Monteith Model Based on Sentinel-2 Data for the Estimation of Actual Evapotranspiration in Vineyards
Authors: García-Gutiérrez Víctor , Stöckle Claudio , Gil Pilar Macarena , Meza Francisco Javier
Published: January 2021

Water scarcity is one of the most important problems of agroecosystems in Mediterranean and semiarid areas, especially for species such as vineyards that largely depend on irrigation. Actual evapotranspiration (ET) is a variable that represents water consumption of a crop, integrating climate and biophysical variables. Actual evapotranspiration models based on remote sensing data from visible bands of Sentinel-2, including Penman-Monteith–Stewart (RS-PMS) and Penman-Monteith–Leuning (RS-PML), were evaluated at different temporal scales in a Cabernet Sauvignon vineyard (Vitis vinifera L.) located in central Chile, and their performance compared with independent ET measurements from an eddy covariance system (EC) and outputs from models based on thermal infrared data from Landsat 7 and Landsat 8, such as Mapping EvapoTranspiration with high Resolution and Internalized Calibration (METRIC) and Priestley–Taylor Two-Source Model (TSEB-PT). The RS-PMS model showed the best goodness of fit for all temporal scales evaluated, especially at instantaneous and daily ET, with root mean squared error (RMSE) of 28.9 Wm−2 and 0.52 mm day−1, respectively, and Willmott agreement index (d1) values of 0.77 at instantaneous scale and 0.7 at daily scale. Additionally, both approaches of RS-PM model were evaluated incorporating a soil evaporation estimation method, one considering the soil water content (fSWC) and the other hand, using the ratio of accumulated precipitation and equivalent evaporation (fZhang), achieving the best fit at instantaneous scale for RS-PMS fSWC method with relative root mean squared error (%RMSE) of 15.2% in comparison to 58.8% of fZhang. Finally, the relevance of the RS-PMS model was highlighted in the assessment and monitoring of vineyard drip irrigation in terms of crop coefficient (Kc) estimation, which is one of the methods commonly used in irrigation planning, yielding a comparable Kc to the one obtained by the EC tower with a bias around 9%.
Complex Principal Component Analysis of Antarctic Ice Sheet Mass Balance
Authors: Zhan Jingang , Shi Hongling , Wang Yong , Yao Yixin
Published: January 2021

Ice sheet changes of the Antarctic are the result of interactions among the ocean, atmosphere, and ice sheet. Studying the ice sheet mass variations helps us to understand the possible reasons for these changes. We used 164 months of Gravity Recovery and Climate Experiment (GRACE) satellite time-varying solutions to study the principal components (PCs) of the Antarctic ice sheet mass change and their time-frequency variation. This assessment was based on complex principal component analysis (CPCA) and the wavelet amplitude-period spectrum (WAPS) method to study the PCs and their time-frequency information. The CPCA results revealed the PCs that affect the ice sheet balance, and the wavelet analysis exposed the time-frequency variation of the quasi-periodic signal in each component. The results show that the first PC, which has a linear term and low-frequency signals with periods greater than five years, dominates the variation trend of ice sheet in the Antarctic. The ratio of its variance to the total variance shows that the first PC explains 83.73% of the mass change in the ice sheet. Similar low-frequency signals are also found in the meridional wind at 700 hPa in the South Pacific and the sea surface temperature anomaly (SSTA) in the equatorial Pacific, with the correlation between the low-frequency periodic signal of SSTA in the equatorial Pacific and the first PC of the ice sheet mass change in Antarctica found to be 0.73. The phase signals in the mass change of West Antarctica indicate the upstream propagation of mass loss information over time from the ocean–ice interface to the southward upslope, which mainly reflects ocean-driven factors such as enhanced ice–ocean interaction and the intrusion of warm saline water into the cavities under ice shelves associated with ice sheets which sit on retrograde slopes. Meanwhile, the phase signals in the mass change of East Antarctica indicate the downstream propagation of mass increase information from the South Pole toward Dronning Maud Land, which mainly reflects atmospheric factors such as precipitation accumulation.
An Improved Method Combining ANN and 1D-Var for the Retrieval of Atmospheric Temperature Profiles from FY-4A/GIIRS Hyperspectral Data
Authors: Huang Pengyu , Guo Qiang , Han Changpei , Zhang Chunming , Yang Tianhang , Huang Shuo
Published: January 2021

In our study, a retrieval method of temperature profiles is proposed which combines an improved one-dimensional variational algorithm (1D-Var) and artificial neural network algorithm (ANN), using FY-4A/GIIRS (Geosynchronous Interferometric Infrared Sounder) infrared hyperspectral data. First, according to the characteristics of the FY-4A/GIIRS observation data using the conventional 1D-Var, we introduced channel blacklists and discarded the channels that have a large negative impact on retrieval, then used the information capacity method for channel selection and introduced a neural network to correct the satellite observation data. The improved 1D-Var effectively used the observation information of 1415 channels, reducing the impact of the error of the satellite observation and radiative transfer model, and realizing the improvement of retrieval accuracy. We subsequently used the improved 1D-Var and ANN algorithms to retrieve the temperature profiles, respectively, from the GIIRS data. The results showed that the accuracy when using ANN is better than using improved 1D-Var in situations where the pressure ranges from 800 hPa to 1000 hPa. Therefore, we combined the improved 1D-Var and ANN method to retrieve temperature profiles for different pressure levels, calculating the error by taking sounding data published by the University of Wyoming as the true values. The results show that the average error of the retrieved temperature profiles is smaller than 2 K when using our method, this method makes the accuracy of the retrieved temperature profiles superior to the accuracy of the GIIRS products from 10 hPa to 575 hPa. All in all, through the combination of the physical retrieval method and the machine learning retrieval method, this paper can certainly provide a reference for improving the accuracy of products.
Auto-Tiler: Variable-Dimension Autoencoder with Tiling for Compressing Intermediate Feature Space of Deep Neural Networks for Internet of Things
Authors: Park Jeongsoo , Kim Jungrae , Ko Jong Hwan
Published: January 2021

Due to limited resources of the Internet of Things (IoT) edge devices, deep neural network (DNN) inference requires collaboration with cloud server platforms, where DNN inference is partitioned and offloaded to high-performance servers to reduce end-to-end latency. As data-intensive intermediate feature space at the partitioned layer should be transmitted to the servers, efficient compression of the feature space is imperative for high-throughput inference. However, the feature space at deeper layers has different characteristics than natural images, limiting the compression performance by conventional preprocessing and encoding techniques. To tackle this limitation, we introduce a new method for compressing DNN intermediate feature space using a specialized autoencoder, called auto-tiler. The proposed auto-tiler is designed to include the tiling process and provide multiple input/output dimensions to support various partitioned layers and compression ratios. The results show that auto-tiler achieves 18% to 67% higher percent point accuracy compared to the existing methods at the same bitrate while reducing the process latency by 73% to 81%. The dimension variability of an auto-tiler also reduces the storage overhead by 62% with negligible accuracy loss.
Silver Nanowires as Electron Transfer Mediators in Electrochemical Catechol Biosensors
Authors: Salvo-Comino Coral , Martin-Pedrosa Fernando , Garcia-Cabezon Cristina , Rodriguez-Mendez Maria Luz
Published: January 2021

The integration of nanomaterials as electron mediators in electrochemical biosensors is taking on an essential role. Due to their high surface-to-volume ratio and high conductivity, metallic nanowires are an interesting option. In this paper, silver nanowires (AgNWs) were exploited to design a novel catechol electrochemical biosensor, and the benefits of increasing the aspect ratio of the electron mediator (nanowires vs. nanoparticles) were analyzed. Atomic force microscopy (AFM) studies have shown a homogeneous distribution of the enzyme along the silver nanowires, maximizing the contact surface. The large contact area promotes electron transfer between the enzyme and the electrode surface, resulting in a Limit of Detection (LOD) of 2.7 × 10−6 M for tyrosinase immobilized onto AgNWs (AgNWs-Tyr), which is one order of magnitude lower than the LOD of 3.2 × 10−5 M) obtained using tyrosinase immobilized onto silver nanoparticles (AgNPs-Tyr). The calculated KM constant was 122 mM. The simultaneous use of electrochemistry and AFM has demonstrated a limited electrochemical fouling that facilitates stable and reproducible detection. Finally, the biosensor showed excellent anti-interference characteristics toward the main phenols present in wines including vanillin, pyrogallol, quercetin and catechin. The biosensor was able to successfully detect the presence of catechol in real wine samples. These results make AgNWs promising elements in nanowired biosensors for the sensitive, stable and rapid voltammetric detection of phenols in real applications.
Methodology for the Implementation of Internal Standard to Laser-Induced Breakdown Spectroscopy Analysis of Soft Tissues
Authors: Šindelářová Anna , Pořízka Pavel , Modlitbová Pavlína , Vrlíková Lucie , Kiss Kateřina , Kaška Milan , Prochazka David , Vrábel Jakub , Buchtová Marcela , Kaiser Jozef
Published: January 2021

The improving performance of the laser-induced breakdown spectroscopy (LIBS) triggered its utilization in the challenging topic of soft tissue analysis. Alterations of elemental content within soft tissues are commonly assessed and provide further insights in biological research. However, the laser ablation of soft tissues is a complex issue and demands a priori optimization, which is not straightforward in respect to a typical LIBS experiment. Here, we focus on implementing an internal standard into the LIBS elemental analysis of soft tissue samples. We achieve this by extending routine methodology for optimization of soft tissues analysis with a standard spiking method. This step enables a robust optimization procedure of LIBS experimental settings. Considering the implementation of LIBS analysis to the histological routine, we avoid further alterations of the tissue structure. Therefore, we propose a unique methodology of sample preparation, analysis, and subsequent data treatment, which enables the comparison of signal response from heterogenous matrix for different LIBS parameters. Additionally, a brief step-by-step process of optimization to achieve the highest signal-to-noise ratio (SNR) is described. The quality of laser–tissue interaction is investigated on the basis of the zinc signal response, while selected experimental parameters (e.g., defocus, gate delay, laser energy, and ambient atmosphere) are systematically modified.
QSMVM: QoS-Aware and Social-Aware Multimetric Routing Protocol for Video-Streaming Services over MANETS
Authors: Palacios Jara Efraín , Mohamad Mezher Ahmad , Aguilar Igartua Mónica , Redondo Rebeca P. Díaz , Fernández-Vilas Ana
Published: January 2021

A mobile ad hoc network (MANET) is a set of autonomous mobile devices connected by wireless links in a distributed manner and without a fixed infrastructure. Real-time multimedia services, such as video-streaming over MANETs, offers very promising applications, e.g., two members of a group of tourists who want to share a video transmitted through the MANET they form, a video-streaming service deployed over a MANET where users watch a film, among other examples. On the other hand, social web technologies, where people actively interact online with others through social networks, are leading to a socialization of networks. Information of interaction among users is being used to provide socially-enhanced software. To achieve this, we need to know the strength of the relationship between a given user and each user they interact with. This strength of the relationship can be measured through a concept called tie strength (TS), first introduced by Mark Granovetter in 1973. In this article, we modify our previous proposal named multipath multimedia dynamic source routing (MMDSR) protocol to include a social metric TS in the decisions taken by the forwarding algorithm. We find a trade-off between the quality of service (QoS) and the trust level between users who form the forwarding path in the MANET. Our goal is to increase the trust metric while the QoS is not affected significantly.
Evaluation Methodology of a Smart Clothing Biomechanical Energy Harvesting System for Mountain Rescuers
Authors: Pękosławski Bartosz , Starzak Łukasz , Dąbrowska Anna , Bartkowiak Grażyna
Published: January 2021

The article presents a methodology developed for the evaluation of biomechanical energy harvesting systems that permits avoiding long-duration outdoor tests while providing realistic input signals and preserving uniform conditions across repeated tests. It consists of two stages: transducer output signal recording and power conversion and storage system measurements. The proposed approach was applied to assess the usefulness of a commercial electromagnetic transducer for supplying a Global Positioning System (GPS) receiver used as an active component of a smart clothing dedicated for mountain rescuers. Electrical power yield measurements have been presented together with ergonomic tests results. They all involved diverse physical activities performed by mountain rescuers that simulated their true operations, but were conducted in a training room for the sake of standardization. By providing reliable data on the transducer’s performance under realistic use conditions, the proposed evaluation procedure revealed that the true energy yield was much smaller not only with respect to the manufacturer’s assertions, but also substantially lower than what was expected based on an independent review which used unrealistic and non-uniform excitations. On the other hand, ergonomics ratings given by potential end users were very high, which demonstrates that the evaluated transducer can still be useful for supplying active cloth components with a lower power demand. The study also revealed that transducer location and orientation strongly affect its performance, which must be taken into account at the first stage of the evaluation procedure. Moreover, physical activity type and conditions (such as motion speed and ground tilt) influence the output power and should be carefully considered when composing a typical case scenario for the second stage.
Universal Verification Platform and Star Simulator for Fast Star Tracker Design
Authors: Schulz Victor Hugo , Marcelino Gabriel Mariano , Seman Laio Oriel , Santos Barros Jeferson , Kim Sangkyun , Cho Mengu , Villarrubia González Gabriel , Leithardt Valderi Reis Quietinho , Bezerra Eduardo Augusto
Published: January 2021

Developing star trackers quickly is non-trivial. Achieving reproducible results and comparing different algorithms are also open problems. In this sense, this work proposes the use of synthetic star images (a simulated sky), allied with the standardized structure of the Universal Verification Methodology as the base of a design approach. The aim is to organize the project, speed up the development time by providing a standard verification methodology. Future rework is reduced through two methods: a verification platform that us shared under a free software licence; and the layout of Universal Verification Methodology enforces reusability of code through an object-oriented approach. We propose a black-box structure for the verification platform with standard interfaces, and provide examples showing how this approach can be applied to the development of a star tracker for small satellites, targeting a system-on-a-chip design. The same test benches were applied to both early conceptual software-only implementations, and later optimized software-hardware hybrid systems, in a hardware-in-the-loop configuration. This test bench reuse strategy was interesting also to show the regression test capability of the developed platform. Furthermore, the simulator was used to inject specific noise, in order to evaluate the system under some real-world conditions.
Feeling of Safety and Comfort towards a Socially Assistive Unmanned Aerial Vehicle That Monitors People in a Virtual Home
Authors: Belmonte Lidia M. , García Arturo S. , Morales Rafael , de la Vara Jose Luis , López de la Rosa Francisco , Fernández-Caballero Antonio
Published: January 2021

Unmanned aerial vehicles (UAVs) represent a new model of social robots for home care of dependent persons. In this regard, this article introduces a study on people’s feeling of safety and comfort while watching the monitoring trajectory of a quadrotor dedicated to determining their condition. Three main parameters are evaluated: the relative monitoring altitude, the monitoring velocity and the shape of the monitoring path around the person (ellipsoidal or circular). For this purpose, a new trajectory generator based on a state machine, which is successfully implemented and simulated in MATLAB/Simulink®, is described. The study is carried out with 37 participants using a virtual reality (VR) platform based on two modules, UAV simulator and VR Visualiser, both communicating through the MQTT protocol. The participants’ preferences have been a high relative monitoring altitude, a high monitoring velocity and a circular path. These choices are a starting point for the design of trustworthy socially assistive UAVs flying in real homes.
The Art of Designing Remote IoT Devices—Technologies and Strategies for a Long Battery Life
Authors: Callebaut Gilles , Leenders Guus , Van Mulders Jarne , Ottoy Geoffrey , De Strycker Lieven , Van der Perre Liesbet
Published: January 2021

Long-range wireless connectivity technologies for sensors and actuators open the door for a variety of new Internet of Things (IoT) applications. These technologies can be deployed to establish new monitoring capabilities and enhance efficiency of services in a rich diversity of domains. Low energy consumption is essential to enable battery-powered IoT nodes with a long autonomy. This paper explains the challenges posed by combining low-power and long-range connectivity. An energy breakdown demonstrates the dominance of transmit and sleep energy. The principles for achieving both low-power and wide-area are outlined, and the landscape of available networking technologies that are suited to connect remote IoT nodes is sketched. The typical anatomy of such a node is presented, and the subsystems are zoomed into. The art of designing remote IoT devices requires an application-oriented approach, where a meticulous design and smart operation are essential to grant a long battery life. In particular we demonstrate the importance of strategies such as “think before you talk” and “race to sleep”. As maintenance of IoT nodes is often cumbersome due to being deployed at hard to reach places, extending the battery life of these devices is critical. Moreover, the environmental impact of batteries further demonstrates the need for a longer battery life in order to reduce the number of batteries used.
Correction: Antanaitis, R., et al. Preliminary Experiment Using Sensors for Cow Health Monitoring after Surgical Treatment for the Left Displacement of the Abomasum. Sensors 2020, 20, 4416
Authors: Antanaitis Ramūnas , Juozaitienė Vida , Televičius Mindaugas , Malašauskienė Dovilė , Merkis Mantvydas , Merkis Eitvydas , Baumgartner Walter
Published: January 2021

The authors wish to make the following corrections to this paper [...]
Functional Electrical Stimulation for Foot Drop in Post-Stroke People: Quantitative Effects on Step-to-Step Symmetry of Gait Using a Wearable Inertial Sensor
Authors: Schifino Giulia , Cimolin Veronica , Pau Massimiliano , da Cunha Maira Jaqueline , Leban Bruno , Porta Micaela , Galli Manuela , Souza Pagnussat Aline
Published: January 2021

The main purpose of the present study was to assess the effects of foot drop stimulators (FDS) in individuals with stroke by means of spatio-temporal and step-to-step symmetry, harmonic ratio (HR), parameters obtained from trunk accelerations acquired using a wearable inertial sensor. Thirty-two patients (age: 56.84 ± 9.10 years; 68.8% male) underwent an instrumental gait analysis, performed using a wearable inertial sensor before and a day after the 10-session treatment (PRE and POST sessions). The treatment consisted of 10 sessions of 20 min of walking on a treadmill while using the FDS device. The spatio-temporal parameters and the HR in the anteroposterior (AP), vertical (V), and mediolateral (ML) directions were computed from trunk acceleration data. The results showed that time had a significant effect on the spatio-temporal parameters; in particular, a significant increase in gait speed was detected. Regarding the HRs, the HR in the ML direction was found to have significantly increased (+20%), while those in the AP and V directions decreased (approximately 13%). Even if further studies are necessary, from these results, the HR seems to provide additional information on gait patterns with respect to the traditional spatio-temporal parameters, advancing the assessment of the effects of FDS devices in stroke patients.
Chronic and Gradual-Onset Injuries and Conditions in the Sport of Surfing: A Systematic Review
Authors: Hanchard Samuel , Duncan Ashley , Furness James , Simas Vini , Climstein Mike , Kemp-Smith Kevin
Published: January 2021

The majority of the previous literature investigating injuries in surfing have focused on acute or traumatic injuries. This systematic review appears to be the first to investigate the literature reporting on chronic and gradual-onset injuries and conditions in surfing populations. A search strategy was implemented on five databases in June 2020 to locate peer-reviewed epidemiological studies on musculoskeletal injuries or non-musculoskeletal conditions in surfing. A modified AXIS Critical Appraisal Tool was used to appraise all included texts. Extracted data included key information relevant to the epidemiology of the injuries and conditions. Twenty journal articles were included with the majority rated as good quality and a substantial agreement between raters (k = 0.724). Spine/back (29.3%), shoulder (22.9%), and head/face/neck (17.5%) were the most frequently reported locations of musculoskeletal injury, whilst the most common mechanism of injury was paddling (37.1%). Exostosis was the most frequently described injury or condition in surfing populations, with the most common grade of severity reported as mild obstruction. The key findings of injury type, location, severity, and mechanism can be used to develop relevant injury management and prevention programs for the surfing population, with an emphasis on chronic or gradual-onset spine/back and shoulder injuries, paddling technique, and education on the development and management of exostosis.
Cross-Cultural Adaptation of the Turkish and Kuwaiti Teacher–Student Relationship Questionnaire in Physical Education (TSRQ- PE Teacher Version): Testing for Measurement Invariance
Authors: Ada Elif Nilay , Ahmad Hasan , Uzun N. Bilge , Jowett Sophia , Kazak Zişan
Published: January 2021

Background: Within the 3Cs (closeness, commitment, and complementarity) theoretical framework of the quality of two-person relationships, a coach–athlete relationship quality questionnaire (CART-Q) was developed and validated to assess the nature of the coach–athlete relationship. In this study, a modified version of the CART-Q for physical education (PE) was adapted to assess the teacher–student relationship quality in the PE context in Turkey and Kuwait. The purpose of this study was to examine the factorial validity of the teacher–student relationship quality questionnaire (TSRQ-PE) within a sample of Turkish and Kuwaiti physical education teachers. Methods: Multigroup confirmatory factor analysis (MGCFA) was used to test the measurement of cultural invariance between these two groups. A total of 175 teachers from Turkey (n = 73) and Kuwait (n = 102) completed the TPRQ-PE. Results: MGCFA supported the factorial validity of the TPRQ-PE in a three first-order factor model across the two countries. Overall, these results add evidence to the psychometric properties of the TPRQ-PE and suggest that this instrument can be applied to measure the quality of the teacher–student relationship within Turkey and Kuwait, although caution may be required when applied to drawing comparisons between these two counties. Conclusions: The results of the present study could help physical educators and researchers in this field to understand the reasons and methods that lead to a quality teacher–student relationship.
Can Existing Theories Explain China’s Outward Foreign Direct Investment in Belt and Road Countries
Authors: Chang Le , Li Jing , Cheong Kee-Cheok , Goh Lim-Thye
Published: January 2021

This study examines the extent to which existing foreign direct investment (FDI) theories apply to Chinese investment in the Belt and Road Initiative (BRI) countries. This is important because existing explanations of Chinese outward FDI (OFDI) generally make scant reference to these theories. By using OFDI data for BRI countries between 2003 and 2017, we tested hypothesizes applicable to existing theories by using both pooled ordinary least squares (PLOS) and stochastic frontier analysis (SFA) methods. The results show that a large part of the existing theories apply to Chinese OFDI. Chinese OFDI is likely to choose countries with big market size, abundant natural resources, cheap unskilled labor, stable politics, good infrastructure, high trade cost and high investment cost. These positive findings notwithstanding, they do not invalidate the alternative factors cited by commentators which have not been subject to direct testing, which may require the use of qualitative analytical approaches.