bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnesium Foliar Supplementation Increases Grain Yield of Soybean and Maize by Improving Photosynthetic Carbon Metabolism and Antioxidant Metabolism
Authors: Rodrigues Vitor Alves , Crusciol Carlos Alexandre Costa , Bossolani João William , Moretti Luiz Gustavo , Portugal José Roberto , Mundt Tamara Thaís , de Oliveira Sirlene Lopes , Garcia Ariani , Calonego Juliano Carlos , Lollato Romulo Pisa
Published: April 2021

(1) Background: The aim of this study was to explore whether supplementary magnesium (Mg) foliar fertilization to soybean and maize crops established in a soil without Mg limitation can improve the gas exchange and Rubisco activity, as well as improve antioxidant metabolism, converting higher plant metabolism into grain yield. (2) Methods: Here, we tested foliar Mg supplementation in soybean followed by maize. Nutritional status of plants, photosynthesis, PEPcase and Rubisco activity, sugar concentration on leaves, oxidative stress, antioxidant metabolism, and finally the crops grain yields were determined. (3) Results: Our results demonstrated that foliar Mg supplementation increased the net photosynthetic rate and stomatal conductance, and reduced the sub-stomatal CO2 concentration and leaf transpiration by measuring in light-saturated conditions. The improvement in photosynthesis (gas exchange and Rubisco activity) lead to an increase in the concentration of sugar in the leaves before grain filling. In addition, we also confirmed that foliar Mg fertilization can improve anti-oxidant metabolism, thereby reducing the environmental stress that plants face during their crop cycle in tropical field conditions. (4) Conclusions: Our research brings the new glimpse of foliar Mg fertilization as a strategy to increase the metabolism of crops, resulting in increased grain yields. This type of biological strategy could be encouraged for wide utilization in cropping systems.
Genome-Wide Association Study of Local Thai Indica Rice Seedlings Exposed to Excessive Iron
Authors: Kaewcheenchai Reunreudee , Vejchasarn Phanchita , Hanada Kousuke , Shirai Kazumasa , Jantasuriyarat Chatchawan , Juntawong Piyada
Published: April 2021

Excess soluble iron in acidic soil is an unfavorable environment that can reduce rice production. To better understand the tolerance mechanism and identify genetic loci associated with iron toxicity (FT) tolerance in a highly diverse indica Thai rice population, a genome-wide association study (GWAS) was performed using genotyping by sequencing and six phenotypic data (leaf bronzing score (LBS), chlorophyll content, shoot height, root length, shoot biomass, and root dry weight) under both normal and FT conditions. LBS showed a high negative correlation with the ratio of chlorophyll content and shoot biomass, indicating the FT-tolerant accessions can regulate cellular homeostasis when encountering stress. Sixteen significant single nucleotide polymorphisms (SNPs) were identified by association mapping. Validation of candidate SNP using other FT-tolerant accessions revealed that SNP:2_21262165 might be associated with tolerance to FT; therefore, it could be used for SNP marker development. Among the candidate genes controlling FT tolerance, RAR1 encodes an innate immune responsive protein that links to cellular redox homeostasis via interacting with abiotic stress-responsive Hsp90. Future research may apply the knowledge obtained from this study in the molecular breeding program to develop FT-tolerant rice varieties.
Epithelial Growth Factor-Anchored on Polycaprolactone/6-deoxy-6-amino-β-cyclodextrin Nanofibers: In Vitro and In Vivo Evaluation
Authors: Moyers-Montoya Edgar D. , Escobedo-González René Gerardo , Vargas-Requena Claudia L. , Garcia-Casillas Perla Elvia , Martínez-Pérez Carlos A.
Published: April 2021

Polycaprolactone (PCL) is a well-known FDA approved biomaterial for tissue engineering. However, its hydrophobic properties limit its use for skin wound healing which makes its functionalization necessary. In this work, we present the fabrication and evaluation of PCL nanofibers by the electrospinning technique, as well as PCL functionalized with 6-deoxy-6-amino-β-cyclodextrin (aminated nanofibers). Afterwards, epithelial growth factor (EGF) was anchored onto hydrophilic PCL/deoxy-6-amino-β-cyclodextrin. The characterization of the three electrospun fibers was made by means of field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR); Confocal-Raman Spectroscopy were used for elucidated the chemical structure, the hydrophilicity was determined by Contact Angle (CA). In vitro cell proliferation test was made by seeding embryonic fibroblast cell line (3T3) onto the electrospun mats and in vivo studies in a murine model were conducted to prove its effectivity as skin wound healing material. The in vitro studies showed that aminated nanofibers without and with EGF had 100 and 150% more cell proliferation of 3T3 cells against the PCL alone, respectively. In vivo results showed that skin wound healing in a murine model was accelerated by the incorporation of the EGF. In addition, the EGF had favorable effects in epidermal cell proliferation. The study demonstrates that a protein of high biological interest like EGF can be attached covalently to the surface of a synthetic material enriched with amino groups. This kind of biomaterial has a great potential for applications in skin regeneration and wound healing.
The II–I Phase Transition Behavior of Butene-1 Copolymers with Hydroxyl Groups
Authors: Li Yuanyuan , Li Tao , Li Wei , Lou Yahui , Liu Liyuan , Ma Zhe
Published: April 2021

The crystallization and II–I phase transition of functionalized polybutene-1 with hydroxyl groups were investigated by differential scanning calorimetry. The results show that the incorporated hydroxyl groups increase the nucleation density but decrease the growth rate in melt crystallization. Interestingly, for the generated tetragonal form II, the presence of polar hydroxyl groups can effectively accelerate the phase transition into the thermodynamically stable modification of trigonal form I, especially with stepwise annealing and high incorporation. Using stepwise annealing, II–I phase transition was enhanced by an additional nucleation step performed at a relatively low temperature, and the optimal nucleation temperature to obtain the maximum transition degree was ‒10 °C, which is independent from the content of hydroxyl groups. Furthermore, the accelerating effect of hydroxyl groups on the II–I transition kinetics can be increased by reducing the crystallization temperature when preparing form II crystallites. These results provide a potential molecular design approach for developing polybutene-1 materials.
Characteristics of Poly(vinyl Alcohol) (PVA) Based Composites Integrated with Green Synthesized Al3+-Metal Complex: Structural, Optical, and Localized Density of State Analysis
Authors: Aziz Shujahadeen B. , Nofal Muaffaq M. , Ghareeb Hewa O. , Dannoun Elham M. A. , Hussen Sarkawt A. , Hadi Jihad M. , Ahmed Khayal K. , Hussein Ahang M.
Published: April 2021

The influence of dispersing Al-metal complex on the optical properties of PVA was investigated using UV–visible spectroscopy. Polymer composite films with various Al3+-complex amounts in the PVA matrix were arranged by solution casting technique by means of distilled water as a widespread solvent. The formation of Al3+-metal complex was verified through Ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) examinations. The addition of Al-complex into the polymer matrix led to the recovery of the optical parameters such as dielectric constant (εr and εi) and refractive index (n). The variations of real and imaginary parts of complex dielectric constant as a function of photon wavelength were studied to calculate localized charge density values (N/m*), high-frequency dielectric constant, relaxation time, optical mobility, optical resistivity, and plasma angular frequency (ωp) of electrons. In proportion with Al3+-complex content, the N/m* values were amplified from 3.68 × 1055 kg−1 m−3 to 109 × 1055 kg−1 m−3. The study of optical parameters may find applications within optical instrument manufacturing. The optical band gap was determined from Tauc’s equation, and the type of electronic transition was specified. A remarkable drop in the optical band gap was observed. The dispersion of static refractive index (no) of the prepared composites was analyzed using the theoretical Wemple–DiDomenico single oscillator model. The average oscillator energy (Eo) and oscillator dispersion energy (Ed) parameters were estimated.
Diffusion Coefficients and Activation Energies of Diffusion of Organic Molecules in Polystyrene below and above Glass Transition Temperature
Authors: Welle Frank
Published: April 2021

General Purpose Polystyrene (GPPS) and High Impact Polystyrene (HIPS) is used in packaging food as well as for technical products. Knowledge of the diffusion behavior of organic molecules in polystyrene (PS) is important for the evaluation of the diffusion and migration process. Within this study, diffusion coefficients were determined in GPPS and HIPS below and above the glass transition temperature. Diffusion coefficients were determined from desorption kinetics into the gas phase using spiked GPPS and HIPS sheets as well as from permeation kinetics through a thin GPPS film. Overall, 187 diffusion coefficients were determined in GPPS and HIPS at temperatures between 0 °C and 115 °C. From the temperature dependency of the diffusion coefficients 45 activation energies of diffusion EA and the pre-exponential factor D0 were determined. As expected, the activation energies of diffusion EA show a strong dependency from the molecular volume of the investigated substances. At the glass transition temperature, only a slight change of the diffusion behavior were observed. Based on EA and D0, prediction parameters for diffusion coefficients were established.
Behaviour of Polymer Filled Composites for Novel Polymer Railway Sleepers
Authors: Ferdous Wahid , Manalo Allan , Salih Choman , Yu Peng , Abousnina Rajab , Heyer Tom , Schubel Peter
Published: April 2021

A novel concept of polymer railway sleeper is proposed in this study that has the potential to meet static performance requirements within the cost of hardwood timber. The existing challenges of composite sleepers, such as low performance or high cost, can be overcome using this innovative concept. Such a proclamation is proven through limit state design criteria and a series of experimentations. Results show that polyurethane foam as an infill material can provide sufficient strength and stiffness properties to the sleeper, but the inadequate screw holding capacity could be a problem. This limitation, however, can be overcome using a particulate filled resin system. The findings of this study will help the railway industry to develop a timber replacement sleeper.
When the Gap between Academic Theology and the Church Makes Possible the Orthodox–Evangelical Dialogue
Authors: Jemna Dănuț , Mănăstireanu Dănuț
Published: April 2021

In the church tradition, we find that the great theologians were also deeply involved in the life of the church as bishops, priests, or pastors who served the believers in their parishes, though, even at that time, practicing theology started to drift apart from performing pastoral work. In Modernity, however, things began to change radically, especially with the development of theology as an academic discipline and even more so with the development of the profession of the theologian specializing in religious studies. This phenomenon penetrated Protestant churches in particular, but it is also found in Orthodoxy. In this study, we advance the hypothesis that, despite its negative connotation, the gap between academic theology and church life opens up the possibility of a promising dialogue between Evangelicals and the Orthodox in Romania. Especially in the last 30 years, theologians from both communities have interacted in the context of doctoral research, scientific conferences, and research projects, although the dialogue between church leaders and hierarchs is almost non-existent. We analyze whether this incipient theological dialogue could possibly create a bridge between the two communities and within them and between academia and the church. We believe that one of the best ways to reduce the distance between them is to build on the interest of the current generation of theologians from both churches in Biblical studies, in Patristic theology, and in the work of the Romanian theologian Dumitru Stăniloae.
Connections of Maghrebin and Sub-Saharan Intellectuals: Trajectories and Representations
Authors: Kedidir Mansour
Published: April 2021

Faced with the complex reality of their countries in the grip of multifaceted crises, the intellectuals in the Maghreb and sub-Saharan Africa are baffled. Indeed, this situation, with a wealth of lessons, ought to challenge them to reflect together on the current upheavals in their societies. Nevertheless, faced with the intricacy of current problems and their heterogeneity, these intellectuals find themselves scattered. Yet, in the past, they were bound by the same objectives. Thus, if the religious elites of the Maghreb had, during the 15th century, forged links with scholars of sub-Saharan Africa, a second wave of intellectuals succeeded them to think about the liberation of Africa and the Pan-African ideal in colonial and post-colonial contexts. However, immediately after this generation disappeared, the one that followed did not resist the disenchantment of the populations and the expansion of Arabism that influenced the formation of a generation of Maghrebin thinkers. With the bankruptcy of the socialist regimes, this hiatus heralded an era of intellectuals crumbling to the point that, with globalisation in the 21st century and the eruption of a plurality of questions, they found themselves helpless in these countries. Apart from a few attempts at building common frameworks for reflection such as those of CODESRIA or the “Esprit Panaf” pavilion at the Algiers International Book Fair, links between intellectuals from the Maghreb and sub-Saharan Africa are rare. Opposed to this type of scholars, mainly Francophone and secularised, a second type of intellectuals, rather Islamised, sharing the same representations, dominate the different spaces of the countries concerned. This paper is an attempt to explore the historical trajectory of these two types of intellectuals and then explain why, in recent decades, such a connection has marked the future of the relationship between the Maghreb and sub-Saharan Africa.
The Potential and Limitations of Critical Raw Material Recycling: The Case of LED Lamps
Authors: Nikulski Julia S. , Ritthoff Michael , von Gries Nadja
Published: April 2021

Supply risks and environmental concerns drive the interest in critical raw material recycling in the European Union. Globally, waste electrical and electronic equipment (WEEE) is projected to increase by almost 40% until 2030. This waste stream can be a source of secondary raw materials. The determination of the economic feasibility of recycling and recovering specific materials is a data-intensive, time-consuming, and case-specific task. This study introduced a two-part evaluation scheme consisting of upper continental crust concentrations and raw material prices as a simple tool to indicate the potential and limitations of critical raw material recycling. It was applied to the case of light-emitting diodes (LED) lamps in the EU. A material flow analysis was conducted, and the projected waste amounts were analyzed using the new scheme. Indium, gallium, and the rare earth elements appeared in low concentrations and low absolute masses and showed only a small revenue potential. Precious metals represented the largest revenue share. Future research should confirm the validity and usefulness of the evaluation scheme.
The Use of Discriminant Analysis to Assess the Risk of Bankruptcy of Enterprises in Crisis Conditions Using the Example of the Tourism Sector in Poland
Authors: Wieprow Joanna , Gawlik Agnieszka
Published: April 2021

The aim of this article is to use multiple discriminant analysis (MDA) and logit models to assess the risk of bankruptcy of companies in the Polish tourism sector in the crisis conditions caused by the COVID-19 pandemic. A review of the literature is used to select models appropriate to analyze the risk of bankruptcy of tourism enterprises listed on the Warsaw Stock Exchange (WSE). The data are from half-year financial statements (the first half of 2019 and 2020, respectively). The obtained results are compared with the current values of the Altman EM-score model and selected financial ratios. An analysis allowed the estimation of the risk of bankruptcy of enterprises from the tourism sector in Poland as well as the assessment of the prognostic value of these models in the tourism sector and the risk of a collapse of this market in Poland. The article fills the research gap created by the negligible use of solvency analysis of the tourism sector and constitutes the basis for estimating the risk of collapse of the tourism sector in a crisis situation.
Spectral Derivatives of Optical Depth for Partitioning Aerosol Type and Loading
Authors: Lin Tang-Huang , Tsay Si-Chee , Lien Wei-Hung , Lin Neng-Huei , Hsiao Ta-Chih
Published: April 2021

Quantifying aerosol compositions (e.g., type, loading) from remotely sensed measurements by spaceborne, suborbital and ground-based platforms is a challenging task. In this study, the first and second-order spectral derivatives of aerosol optical depth (AOD) with respect to wavelength are explored to determine the partitions of the major components of aerosols based on the spectral dependence of their particle optical size and complex refractive index. With theoretical simulations from the Second Simulation of a Satellite Signal in the Solar Spectrum (6S) model, AOD spectral derivatives are characterized for collective models of aerosol types, such as mineral dust (DS) particles, biomass-burning (BB) aerosols and anthropogenic pollutants (AP), as well as stretching out to the mixtures among them. Based on the intrinsic values from normalized spectral derivatives, referenced as the Normalized Derivative Aerosol Index (NDAI), a unique pattern is clearly exhibited for bounding the major aerosol components; in turn, fractions of the total AOD (fAOD) for major aerosol components can be extracted. The subtlety of this NDAI method is examined by using measurements of typical aerosol cases identified carefully by the ground-based Aerosol Robotic Network (AERONET) sun–sky spectroradiometer. The results may be highly practicable for quantifying fAOD among mixed-type aerosols by means of the normalized AOD spectral derivatives.
Joint Task Offloading, Resource Allocation, and Security Assurance for Mobile Edge Computing-Enabled UAV-Assisted VANETs
Authors: He Yixin , Zhai Daosen , Huang Fanghui , Wang Dawei , Tang Xiao , Zhang Ruonan
Published: April 2021

In this paper, we propose a mobile edge computing (MEC)-enabled unmanned aerial vehicle (UAV)-assisted vehicular ad hoc network (VANET) architecture, based on which a number of vehicles are served by UAVs equipped with computation resource. Each vehicle has to offload its computing tasks to the proper MEC server on the UAV due to the limited computation ability. To counter the problems above, we first model and analyze the transmission model and the security assurance model from the vehicle to the MEC server on UAV, and the task computation model of the local vehicle and the edge UAV. Then, the vehicle offloading problem is formulated as a multi-objective optimization problem by jointly considering the task offloading, the resource allocation, and the security assurance. For tackling this hard problem, we decouple the multi-objective optimization problem as two subproblems and propose an efficient iterative algorithm to jointly make the MEC selection decision based on the criteria of load balancing and optimize the offloading ratio and the computation resource according to the Lagrangian dual decomposition. Finally, the simulation results demonstrate that our proposed scheme achieves significant performance superiority compared with other schemes in terms of the successful task processing ratio and the task processing delay.
High-Resolution Aerial Detection of Marine Plastic Litter by Hyperspectral Sensing
Authors: Balsi Marco , Moroni Monica , Chiarabini Valter , Tanda Giovanni
Published: April 2021

An automatic custom-made procedure is developed to identify macroplastic debris loads in coastal and marine environment, through hyperspectral imaging from unmanned aerial vehicles (UAVs). Results obtained during a remote-sensing field campaign carried out in the seashore of Sassari (Sardinia, Italy) are presented. A push-broom-sensor-based spectral device, carried onboard a DJI Matrice 600 drone, was employed for the acquisition of spectral data in the range 900−1700 nm. The hyperspectral platform was realized by assembling commercial devices, whereas algorithms for mosaicking, post-flight georeferencing, and orthorectification of the acquired images were developed in-house. Generation of the hyperspectral cube was based on mosaicking visible-spectrum images acquired synchronously with the hyperspectral lines, by performing correlation-based registration and applying the same translations, rotations, and scale changes to the hyperspectral data. Plastics detection was based on statistically relevant feature selection and Linear Discriminant Analysis, trained on a manually labeled sample. The results obtained from the inspection of either the beach site or the sea water facing the beach clearly show the successful separate identification of polyethylene (PE) and polyethylene terephthalate (PET) objects through the post-processing data treatment based on the developed classifier algorithm. As a further implementation of the procedure described, direct real-time processing, by an embedded computer carried onboard the drone, permitted the immediate plastics identification (and visual inspection in synchronized images) during the UAV survey, as documented by short video sequences provided in this research paper.
Landslide Awareness System (LAwS) to Increase the Resilience and Safety of Transport Infrastructure: The Case Study of Pan-American Highway (Cuenca–Ecuador)
Authors: Miele Pietro , Di Napoli Mariano , Guerriero Luigi , Ramondini Massimo , Sellers Chester , Annibali Corona Mariagiulia , Di Martire Diego
Published: April 2021

In most countries, landslides have caused severe socioeconomic impacts on people, cities, industrial establishments, and lifelines, such as highways, railways, and communication network systems. Socioeconomic losses due to slope failures are very high and they have been growing as the built environment expands into unstable hillside areas under the pressures of growing populations. Human activities as the construction of buildings, transportation routes, dams, and artificial canals have often been a major factor for the increasing damage due to slope failures. When recovery actions are not durable from an economic point of view, increasing the population’s awareness is the key strategy to reduce the effects of natural and anthropogenic events. Starting from the case study of the Pan-American Highway (the Ecuadorian part), this article shows a multi-approach strategy for infrastructure monitoring. The combined use of (i) DInSAR technique for detection of slow ground deformations, (ii) field survey activities, and (iii) the QPROTO tool for analysis of slopes potentially prone to collapse allowed us to obtain a first cognitive map to better characterize 22 km of the highway between the cities of Cuenca and Azogues. This study is the primary step in the development of a landslide awareness perspective to manage risk related to landslides along infrastructure corridors, increasing user safety and providing stakeholders with a management system to plan the most urgent interventions and to ensure the correct functionality of the infrastructure.
Detecting Offshore Drilling Rigs with Multitemporal NDWI: A Case Study in the Caspian Sea
Authors: Zhu Hui , Jia Gongxu , Zhang Qingling , Zhang Shan , Lin Xiaoli , Shuai Yanmin
Published: April 2021

Offshore drilling rigs are the foundation of oil and gas exploitation in water areas. Their spatial and temporal distribution, state attributes and other information directly reflect the exploitation level of regional oil and gas resources. Therefore, it is very important to build an automatic detecting method for offshore drilling rigs with good performance to accurately capture the temporal and spatial distribution and state of oil and gas exploitation activities. At present, there are two main groups of methods for offshore drilling rigs: invariant feature-based methods and nighttime firelight-based methods. Methods based on invariant location are more subjective in terms of their parameter settings and require intensive computation. Nighttime light-based methods are largely unable to identify offshore drilling rigs without associated waste gas ignition. Furthermore, multiple offshore drilling rigs in close proximity to one another cannot be effectively distinguished with low spatial resolution imagery. To address these shortcomings, we propose a new method for the automatic identification of offshore drilling rigs based on Landsat-7 ETM+ images from 2018 to 2019, taking the Caspian Sea as the research area. We build a nominal annual cloud and cloud shadow-free Normalized Difference Water Index (NDWI) composite by designing an optimal NDWI compositing method based of the influence of cloud and cloud shadow on the NDWI values of water, bare land (island) and offshore drilling rigs. The classification of these objects is simultaneously done during the compositing process, with the following rules: water body (Max_NDWI > 0.55), bare land (island) (Min_NDWI < −0.05) and offshore drilling rig (0 < Mean_NDWI < 0.4). A threshold segmentation and postprocessing were carried out to further refine the results. Using this method, 497 offshore platforms were automatically identified using a nominal annual cloud and cloud shadow-free NDWI composite image and Google Earth Engine. Validation using Sentinel-2 Multispectral Imager (MSI) and Google Earth images demonstrated that the correct rate of offshore drilling rig detection in the Caspian Sea is 90.2%, the missing judgment rate is 5.3% and the wrong judgment rate is 4.5%, proving the performance of the proposed method. This method can be used to identify offshore drilling rigs within a large water surface area relatively quickly, which is of great significance for exploring the exploitation status of offshore oil and gas resources. It can also be extended to finer spatial resolution optical remote sensing images; thus small-size drilling rigs can be effectively detected.
Morphodynamic Controls for Growth and Evolution of a Rubble Coral Island
Authors: Talavera Lara , Vila-Concejo Ana , Webster Jody M. , Smith Courtney , Duce Stephanie , Fellowes Thomas E. , Salles Tristan , Harris Daniel , Hill Jon , Figueira Will , Hacker Jörg
Published: April 2021

Rubble islands are dynamic sedimentary features present on reef platforms that evolve under a variety of morphodynamic processes and controlling mechanisms. They provide valuable inhabitable land for small island nations, critical habitat for numerous species, and are threatened by climate change. Aiming to investigate the controlling mechanisms dictating the evolution of One Tree Island (OTI), a rubble island in the Southern Great Barrier Reef, we combined different remotely-sensed data across varying timescales with wave data extracted from satellite altimetry and cyclone activity. Our findings show that (1) OTI had expanded by 7% between 1978 and 2019, (2) significant gross planform decadal adjustments were governed by the amount, intensity, proximity, and relative position of cyclones as well as El Niño Southern Oscillation (ENSO) phases, and (3) the mechanisms of island growth involve rubble spits delivering and redistributing rubble to the island through alongshore sediment transport and wave overtopping. Frequent short-term monitoring of the island and further research coupling variations in the different factors driving island change (i.e., sediment availability, reef-wave interactions, and extreme events) are needed to shed light on the future trajectory of OTI and other rubble islands under a climate change scenario.
A Neural-Network Based Spatial Resolution Downscaling Method for Soil Moisture: Case Study of Qinghai Province
Authors: Lv Aifeng , Zhang Zhilin , Zhu Hongchun
Published: April 2021

Currently, soil-moisture data extracted from microwave data suffer from poor spatial resolution. To overcome this problem, this study proposes a method to downscale the soil moisture spatial resolution. The proposed method establishes a statistical relationship between low-spatial-resolution input data and soil-moisture data from a land-surface model based on a neural network (NN). This statistical relationship is then applied to high-spatial-resolution input data to obtain high-spatial-resolution soil-moisture data. The input data include passive microwave data (SMAP, AMSR2), active microwave data (ASCAT), MODIS data, and terrain data. The target soil moisture data were collected from CLDAS dataset. The results show that the addition of data such as the land-surface temperature (LST), the normalized difference vegetation index (NDVI), the normalized shortwave-infrared difference bare soil moisture indices (NSDSI), the digital elevation model (DEM), and calculated slope data (SLOPE) to active and passive microwave data improves the retrieval accuracy of the model. Taking the CLDAS soil moisture data as a benchmark, the spatial correlation increases from 0.597 to 0.669, the temporal correlation increases from 0.401 to 0.475, the root mean square error decreases from 0.051 to 0.046, and the mean absolute error decreases from 0.041 to 0.036. Triple collocation was applied in the form of [NN, FY3C, GEOS-5] based on the extracted retrieved soil-moisture data to obtain the error variance and correlation coefficient between each product and the actual soil-moisture data. Therefore, we conclude that NN data, which have the lowest error variance (0.00003) and the highest correlation coefficient (0.811), are the most applicable to Qinghai Province. The high-spatial-resolution data obtained from the NN, CLDAS data, SMAP data, and AMSR2 data were correlated with the ground-station data respectively, and the result of better NN data quality was obtained. This analysis demonstrates that the NN-based method is a promising approach for obtaining high-spatial-resolution soil-moisture data.
A Novel Focal Phi Loss for Power Line Segmentation with Auxiliary Classifier U-Net
Authors: Jaffari Rabeea , Hashmani Manzoor Ahmed , Reyes-Aldasoro Constantino Carlos
Published: April 2021

The segmentation of power lines (PLs) from aerial images is a crucial task for the safe navigation of unmanned aerial vehicles (UAVs) operating at low altitudes. Despite the advances in deep learning-based approaches for PL segmentation, these models are still vulnerable to the class imbalance present in the data. The PLs occupy only a minimal portion (1–5%) of the aerial images as compared to the background region (95–99%). Generally, this class imbalance problem is addressed via the use of PL-specific detectors in conjunction with the popular class balanced cross entropy (BBCE) loss function. However, these PL-specific detectors do not work outside their application areas and a BBCE loss requires hyperparameter tuning for class-wise weights, which is not trivial. Moreover, the BBCE loss results in low dice scores and precision values and thus, fails to achieve an optimal trade-off between dice scores, model accuracy, and precision–recall values. In this work, we propose a generalized focal loss function based on the Matthews correlation coefficient (MCC) or the Phi coefficient to address the class imbalance problem in PL segmentation while utilizing a generic deep segmentation architecture. We evaluate our loss function by improving the vanilla U-Net model with an additional convolutional auxiliary classifier head (ACU-Net) for better learning and faster model convergence. The evaluation of two PL datasets, namely the Mendeley Power Line Dataset and the Power Line Dataset of Urban Scenes (PLDU), where PLs occupy around 1% and 2% of the aerial images area, respectively, reveal that our proposed loss function outperforms the popular BBCE loss by 16% in PL dice scores on both the datasets, 19% in precision and false detection rate (FDR) values for the Mendeley PL dataset and 15% in precision and FDR values for the PLDU with a minor degradation in the accuracy and recall values. Moreover, our proposed ACU-Net outperforms the baseline vanilla U-Net for the characteristic evaluation parameters in the range of 1–10% for both the PL datasets. Thus, our proposed loss function with ACU-Net achieves an optimal trade-off for the characteristic evaluation parameters without any bells and whistles. Our code is available at Github.
Prediction of Drill Bit Breakage Using an Infrared Sensor
Authors: Jeong Min-Jae , Lee Sang-Woo , Jang Woong-Ki , Kim Hyung-Jin , Seo Young-Ho , Kim Byeong-Hee
Published: April 2021

In this paper, a novel drill bit breakage prediction method featuring a low-cost commercial infrared sensor to monitor drill bit corner wear is proposed. In the proposed method, the drill bit outer corner wear state can be monitored by measuring reflected infrared light because the reflection phenomenon is influenced by wear, edge shape, and surface roughness of the drill bit. In the experiments, a titanium workpiece was drilled without using cutting fluid to accelerate drill bit fracture. After drilling a hole in the workpiece, reflected infrared light was measured for the drill bit rotating at 100 rpm. Collected data on intensity of infrared light reflected from the circumferential surface of the drill bit versus the rotation angle of the drill bit were considered to predict tool breakage; two significant positions to predict tool breakage were found from the reflected infrared light graphs. By defining gradient vectors from the slopes of the reflected infrared light curves, a reliable criterion for determining drill bit breakage could be established. The proposed method offers possibilities for new measurement and analysis methods that have not been used in conventional tool wear and damage studies. The advantage of the proposed method is that the measurement device is easy to install and the measured signal is resistant to electromagnetic noise and ambient temperature because optical fiber is used as the signal transmission medium. It also eliminates the need for complex analysis of the measured signal, eliminating the need for a high-performance analyzer and reducing analysis time.
Continuous Resonance Tuning without Blindness by Applying Nonlinear Properties of PIN Diodes
Authors: Luo Yong , Liu Hongtao , He Yiming , Cui Hengrong , Yang Guangli
Published: April 2021

Metamaterial antennas consisting of periodical units are suitable for achieving tunable properties by employing active elements to each unit. However, for compact metamaterials with a very limited number of periodical units, resonance blindness exists. In this paper, we introduce a method to achieve continuous tuning without resonance blindness by exploring hence, taking advantage of nonlinear properties of PIN diodes. First, we obtain the equivalent impedance of the PIN diode through measurements, then fit these nonlinear curves with mathematical expressions. Afterwards, we build the PIN diode model with these mathematical equations, making it compatible with implementing co-simulation between the passive electromagnetic model and the active element of PIN diodes and, particularly, the nonlinear effects can be considered. Next, we design a compact two-unit metamaterial antenna as an example to illustrate the electromagnetic co-simulation. Finally, we implement the experiments with a micro-control unit to validate this method. In addition, the nonlinear stability and the supplying voltage tolerance of nonlinear states for both two kinds of PIN diodes are investigated as well. This method of obtaining smooth tuning with nonlinear properties of PIN diodes can be applied to other active devices, if only PIN diodes are utilized.
The Smart-Insole Dataset: Gait Analysis Using Wearable Sensors with a Focus on Elderly and Parkinson’s Patients
Authors: Chatzaki Chariklia , Skaramagkas Vasileios , Tachos Nikolaos , Christodoulakis Georgios , Maniadi Evangelia , Kefalopoulou Zinovia , Fotiadis Dimitrios I. , Tsiknakis Manolis
Published: April 2021

Gait analysis is crucial for the detection and management of various neurological and musculoskeletal disorders. The identification of gait events is valuable for enhancing gait analysis, developing accurate monitoring systems, and evaluating treatments for pathological gait. The aim of this work is to introduce the Smart-Insole Dataset to be used for the development and evaluation of computational methods focusing on gait analysis. Towards this objective, temporal and spatial characteristics of gait have been estimated as the first insight of pathology. The Smart-Insole dataset includes data derived from pressure sensor insoles, while 29 participants (healthy adults, elderly, Parkinson’s disease patients) performed two different sets of tests: The Walk Straight and Turn test, and a modified version of the Timed Up and Go test. A neurologist specialized in movement disorders evaluated the performance of the participants by rating four items of the MDS-Unified Parkinson’s Disease Rating Scale. The annotation of the dataset was performed by a team of experienced computer scientists, manually and using a gait event detection algorithm. The results evidence the discrimination between the different groups, and the verification of established assumptions regarding gait characteristics of the elderly and patients suffering from Parkinson’s disease.
Planar Body-Mounted Sensors for Electromagnetic Tracking
Authors: Cavaliere Marco , Jaeger Herman Alexander , O’Donoghue Kilian , Cantillon-Murphy Pádraig
Published: April 2021

Electromagnetic tracking is a safe, reliable, and cost-effective method to track medical instruments in image-guided surgical navigation. However, patient motion and magnetic field distortions heavily impact the accuracy of tracked position and orientation. The use of redundant magnetic sensors can help to map and mitigate for patient movements and magnetic field distortions within the tracking region. We propose a planar inductive sensor design, printed on PCB and embedded into medical patches. The main advantage is the high repeatability and the cost benefit of using mass PCB manufacturing processes. The article presents new operative formulas for electromagnetic tracking of planar coils on the centimetre scale. The full magnetic analytical model is based on the mutual inductance between coils which can be approximated as being composed by straight conductive filaments. The full model is used to perform accurate system simulations and to assess the accuracy of faster simplified magnetic models, which are necessary to achieve real-time tracking in medical applications.
Drone vs. Bird Detection: Deep Learning Algorithms and Results from a Grand Challenge
Authors: Coluccia Angelo , Fascista Alessio , Schumann Arne , Sommer Lars , Dimou Anastasios , Zarpalas Dimitrios , Méndez Miguel , de la Iglesia David , González Iago , Mercier Jean-Philippe , Gagné Guillaume , Mitra Arka , Rajashekar Shobha
Published: April 2021

Adopting effective techniques to automatically detect and identify small drones is a very compelling need for a number of different stakeholders in both the public and private sectors. This work presents three different original approaches that competed in a grand challenge on the “Drone vs. Bird” detection problem. The goal is to detect one or more drones appearing at some time point in video sequences where birds and other distractor objects may be also present, together with motion in background or foreground. Algorithms should raise an alarm and provide a position estimate only when a drone is present, while not issuing alarms on birds, nor being confused by the rest of the scene. In particular, three original approaches based on different deep learning strategies are proposed and compared on a real-world dataset provided by a consortium of universities and research centers, under the 2020 edition of the Drone vs. Bird Detection Challenge. Results show that there is a range in difficulty among different test sequences, depending on the size and the shape visibility of the drone in the sequence, while sequences recorded by a moving camera and very distant drones are the most challenging ones. The performance comparison reveals that the different approaches perform somewhat complementary, in terms of correct detection rate, false alarm rate, and average precision.
Morbidity of in-hospital purulent-septic infections of adults patients after different types of endovascular cardiosurgical operations
Authors: Sergevnin Viktor Ivanovich , Kudryavtseva Larisa Gennadievna , Zolotukhina Anna Igorevna
Published: April 2021

An estimate of the incidence of nosocomial purulent-septic infections (GSI) of adult patients after various types of closed heart surgery according to the results of a study of medical records of 3275 patients is presented. It was established that the incidence rate of typical GSI after endovascular cardiac surgery was 3.1, with prenosological forms — 3.9 per 1000 operations. The main clinical options for postoperative GSI were infections in the field of surgical intervention, community-acquired pneumonia, urinary tract infection and bloodstream infection. There were no statistically significant differences between the incidence of GSI after stenting of the coronary arteries, operations for heart rhythm disturbances, stenosis of the carotid artery and other operations. The low incidence of GSI after closed heart surgery is due to the short duration of surgery, as well as the absence or short-term resuscitation of patients.
Historical retrospective of scientific thought in the discourse of a healthy lifestyle: Russian review
Authors: Kaunova E.
Published: April 2021

This paper analyzes some concepts of Russian and foreign thinkers in the discourse of a healthy lifestyle. Despite numerous objective and subjective components of health, lifestyle is recognized as the most significant and effective component of the definition of health.
"My genius will fl y forever..."
Authors: Bykeeva V.
Published: April 2021

Methodical development of activities for children of senior school age and students of 1–2 courses of universities dedicated to the 205th anniversary of the birth of the great Russian writer, poet, artist Mikhail Yurievich Lermontov.
Almazovo Estate: History and Contemporaneity
Authors: Akimova A.
Published: April 2021

The paper is based on the analysis of Russian, Inglish and Italian sources and represents the reception of the Demidov’s estate Almazovo by our contemporaries. The electronic resources about the estate containing legends, fictions and often unreliable information are analyzed for the first time. The estate of the Moscow Region and especially its park preserved now attracts the attention of Russian and foreign travelers. However, nobody managed to discover the mystery of this ‘mysterious ensemble of the Moscow Region estate of the Ural mine owners Demidov’ (L.A. Perfilyeva). According to the researchers, the garden and park of Almazovo estate are unique because of its Masonic signs. The multi-valued system of Masonic signs in the arrangement of the park such as the system of canals and labyrinths, the hill and the pavilion, the location of islands can be perceived as a manifestation of the bizarre plan of the rich owner inspired by Venice which was quite common in the manor culture of the end of XVIII–XIXth centuries and as ‘a secret signs’ artfully embodied in the Masonic park, the only one park preserved in the suburbs of Moscow.
State of the reproductive potential of the domestic breeding stock of herbivorous fish
Authors: Servetnik Grigory Emelyanovich
Published: April 2021

The industry program provides for increasing the share of highly productive carp, including herbivores (whit carp, silver carp, grass carp and black carp), in the total production from 20 to 50% by 2020. However, currently in Russia there are only two certified breeding farms for the reproduction of breeding material of these fish: fish farm «Shaparievsky» of the Krasnodar territory and «Rybopitomnik Chaganskij» of the Astrakhan region. In modern economic conditions, not enough attention is paid to breeding work, there are not enough specialists-breeders on the ground, which negatively affects the quality of work carried out, there is a closely related crossing of producers. Since the end of the last century, there has been a negative impact of inbred depression in the breeding of herbivorous fish. In addition, the cultivation and maintenance of fish in mixed planting conditions in the technological cycle of carp cultivation cause unsatisfactory development and physiological state of mature producers. To exclude inbred depression and use the effect of heterosis, the recommended method of selection is interline hybridization using two «natural lines» — populations from the Yangtze river (line of Chinese origin) and the Amur river (line of Amur origin). This makes it possible to avoid closely related crossing and allows you to count on getting the effect of heterosis. When crossing cupids and silver carp of Chinese and Amur origin, the effect of heterosis is equal to 10–15% (for the survival of juveniles and the growth of crossbreeds in the first year of life). To control the origin of the white carp, 4 species-specific biochemical markers were identified: myogenes, prealbumids, enzymes — alkaline phosphatase and tetrazolium oxidase. They can be used to control the origin and the industrial hybridization of white with silver carp spotted silver carp. For grass carp, biochemical polymorphism of proteins and enzymes was also detected: serum and muscle esterases, superoxide dismutase, and vitellogenins.