bluuebunny/crossref_metadata_2025 huggingface dataset:
Shaking Table Test of a Transfer-Purge Chamber in Nuclear Island Structure
Authors: Liu Xuchen , Li Xiaojun , Wang Xiaohui , Wang Ning , Li Zaixian
Published: January 2022

The transfer-purge chamber is an operation room for nuclear fuel transport and purging in a nuclear power plant, which has a demand for structural reliability and radiation protection. The transfer-purge chamber has features such as large curvature, heavy concrete, long overhang, and irregular cross-sections, and it is constructed of double steel plates reinforced concrete (SC) structure. This study performed shaking table tests for a 1:4.5 scale model of the transfer-purge chamber. Three sets of ground motions were input in the scale model in the horizontal and vertical directions to study its structural reliability and seismic performance. Acceleration response and strain response of the structure were analyzed to evaluate the dynamic characteristics of the transfer-purge chamber under the ground motion. The results show that the transfer-purge chamber has great stiffness and short periods. The periods slightly increase with the rise of intensity of seismic ground motions. Under the excitation of ground motions, the dynamic response of the transfer-purge chamber is slight. No obvious deformation or damage occurred on the transfer-purge chamber, and cracking in concrete or buckling on steel plate did not appear. The transfer-purge chamber has excellent seismic performance, and it is sufficiently safe and reliable from a structural perspective.
Fabrication of Lead Free Borate Glasses Modified by Bismuth Oxide for Gamma Ray Protection Applications
Authors: Al-Hadeethi Yas , Sayyed M. I. , Barasheed Abeer Z. , Ahmed Moustafa , Elsafi Mohamed
Published: January 2022

In the present work, bismuth borate glass samples with the composition of (99-x) B2O3 + 1Cr2O3 + (x) Bi2O3 (x = 0, 5, 10, 15, 20, and 25 wt %) were prepared using the melt quenching technique. The mass attenuation coefficient (MAC) of the prepared glass samples was measured through a narrow beam technique using a NaI(Tl) scintillation detector. Four point sources were used (241Am, 133Ba, 152Eu, and 137Cs) to measure the MAC for the prepared glasses. The experimental data were compared with the theoretical results obtained from the XCOM, and it was shown that for all samples at all tested energies, the relative deviation between the samples is less than 3%. This finding signifies that the experimental data can adequately be used to evaluate the shielding ability of the glasses. The MAC of the sample with x = 25 wt % was compared with different lead borate glasses and the results indicated that the present sample has high attenuation which is very close to commercial lead borate glasses. We determined the transmission factor (TF), and found that it is small at low energies and increases as the energy increases. The addition of Bi2O3 leads to reduction in the TF values, which improves the shielding performance of the glass system. The half value layer (HVL) of the BCrBi-10 sample was 0.400 cm at 0.595 MeV, 1.619 cm at 0.2447 MeV, and 4.946 cm at 1.4080 MeV. Meanwhile, the HVL of the BCrBi-20 sample is equal to 0.171 and 4.334 cm at 0.0595 and 1.4080 MeV, respectively. The HVL data emphasize that higher energy photons tend to penetrate through the glasses with greater ease than lower energy photons. Furthermore, the fast neutron removable cross section (FNRC) was determined for the present samples and compared with lead borate glass and concrete, and the results showed a remarkable superiority of the bismuth borate glass samples.
Numerical Modelling of the Dynamic Voltage in HTS Materials under the Action of DC Transport Currents and Different Oscillating Magnetic Fields
Authors: Shen Boyang , Chen Xiaoyuan , Fu Lin , Hao Luning , Coombs Tim
Published: January 2022

The dynamic voltage is a unique phenomenon of superconducting materials. It arises when the superconductor is carrying a DC transport current and spontaneously in subject to an AC magnetic field. This study excavates the aspects that previous studies have not comprehensively investigated: the dynamic voltage in a DC-carrying superconducting tape exposed to different oscillating AC magnetic fields. First, the fundamental physics of dynamic voltage/flux of superconductors is reviewed and further analysed in detail. We used the superconducting modelling method using the H-formulation merged into the finite-element method (FEM) software, to re-produce the typical dynamic voltage behaviour of a superconducting tape. The modelling was verified by both the analytical and experimental results, in order to precisely prove the reliability of the modelling. Afterwards, the modelling was performed for a DC-carrying superconducting tape under four different oscillating magnetic fields (sine, triangle, sawtooth and square), and their corresponding dynamic voltages and energy losses were analysed and compared. Results show the sinusoidal magnetic field can lead to the optimal combination of reasonable dynamic voltage but relatively lower loss, which is suitable for those superconducting applications requiring dynamic voltage as the energy source, e.g., flux pumps. This article presents novel investigation and analysis of the dynamic voltage in superconducting materials, and both the methodology and results can provide useful information for the future design/analysis of superconducting applications with DC transport currents and AC magnetic fields.
Impact of APRF+ in Combination with Autogenous Fibroblasts on Release Growth Factors, Collagen, and Proliferation and Migration of Gingival Fibroblasts: An In Vitro Study
Authors: Sterczała Barbara , Chwiłkowska Agnieszka , Szwedowicz Urszula , Kobielarz Magdalena , Chwiłkowski Bartłomiej , Dominiak Marzena
Published: January 2022

The present study aimed to compare the action of advanced platelet-rich fibrin (A-PRF+) alone with the action of A-PRF+ combined with autologous gingival fibroblasts. The components released from A-PRF+ conditioned with autogenous fibroblasts that were quantified in the study were fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), trans-forming growth factor-beta1 and 2 (TGFβ1 and TGFβ2), and soluble collagen. A-PRF+ combined with fibroblasts demonstrated significantly higher values of released VEGF at every time point and, after 7 days, significantly higher values of released TGFβ2. A viability test after 72 h showed a significant increase in proliferation fibroblasts after exposition to the factors released from A-PRF+ combined with fibroblasts. Similarly, the degree of wound closure after 48 h was significantly higher for the factors released from A-RRF+ alone and the factors released from A-RRF+ combined with fibroblasts. These results imply that platelet-rich fibrin (PRF) enhanced with fibroblasts can be an alternative method of connective tissue transplantation.
Sorption Studies of Tetracycline Antibiotics on Hydroxyapatite (001) Surface—A First-Principles Insight
Authors: Song Jiaming , Cui Naiyu , Mao Xuran , Huang Qixuan , Lee Eui-Seok , Jiang Hengbo
Published: January 2022

Owing to the limitations of traditional systemic drug delivery in the treatment of bone diseases with side effects on normal cells, the selection of materials with high affinities for bones, as targeting ligands to modify drug carriers, has become an important research topic. Tetracyclines (TCs) have an adsorption effect on hydroxyapatite (HAp). Thus, they can be used as bone-targeting ligands and combined with drug carriers. In this study, density functional theory is used to analyze the interaction mechanism of TC, oxytetracycline (OTC), chlortetracycline, and HAp. We calculate the electrostatic potential (ESP) and molecular orbitals to predict the possible binding sites of TCs on the HAp surface. The adsorption energy is used to compare the affinities of the three TCs to HAp. An independent gradient model analysis is performed to study the weak interaction between TCs and HAp. The coordination bond between TCs and the HAp surface is evaluated by conducting a charge density difference analysis. The results show that OTC has the highest affinity to HAp because the introduction of hydroxyl groups change the adsorption configuration of OTC. Thus, OTC adsorbed on HAp in a broken-line shape exposes more binding sites. This study provides a theoretical basis for TCs as bone-targeting ligands in treating bone diseases and in improving the safety of treatment by selecting different bone-targeting ligands.
Influence of Higher Order Viscous and Thermal Effects on an Ultrasonic Wave Reflected from the First Interface of a Porous Material
Authors: Fellah Zine El Abiddine , Roncen Rémi , Ongwen Nicholas O. , Ogam Erick , Fellah Mohamed , Depollier Claude
Published: January 2022

Ultrasound propagation in porous materials involves some higher order physical parameters whose importance depends on the acoustic characteristics of the materials. This article concerns the study of the influence of two parameters recently introduced, namely, the viscous and thermal surfaces, on the acoustic wave reflected by the first interface of a porous material with a rigid structure. These two parameters describe the fluid/structure interactions in a porous medium during the propagation of the acoustic wave in the high-frequency regime. Both viscous and thermal surfaces are involved in Laurent expansion, which is limited to the dynamic tortuosity and compressibility to a higher order and corrects the visco-thermal losses. A sensitivity study is performed on the modulus of the reflection coefficient at the first interface as a function of frequency and on the waveforms reflected by the porous material in the time domain. The results of this study show that highly absorbent porous materials are the most sensitive to viscous and thermal surfaces, which makes the consideration of these two parameters paramount for the characterization of highly absorbent porous materials using the waves reflected from the first interface.
Investigation of the Effect of Temperature on the Wear Rate and Airborne Noise in Sliding Wear
Authors: Lontin Kevin , Khan Muhammad , Alharbi Bander
Published: January 2022

When friction processes occur, wear is generated. The generation of wear also leads to airborne noise. There have been many research studies on wear and its correlation with airborne noise, but most research has focused on experimental aspects, and theoretical models are rare. Furthermore, analytical models do not fully account for the wear and airborne noise generation, especially at an asperitical level. One model was developed that gave a reasonable quantification for the relationship between wear and airborne noise generation at an asperitical level under room temperature. In this paper, the accuracy of the model is assessed at higher temperatures. Two materials were set up on a tribometer (aluminium and iron) at 300 RPM. The samples were tested at two different temperatures (40 and 60 degrees) and two different loads were applied (10 N and 20 N). The model computed the predicted wear and sound pressure, and it was compared with the experimental results. The errors are larger for the wear than when the model was validated at room temperature. However, the increase in the error for the sound pressure was smaller at higher temperatures (approximately 20–30%). This is due to the assumptions that were made in the initial model, which are exacerbated when higher temperatures are applied. For example, flash temperatures were neglected in the original model. However, when initial heat is applied, the effects of flash temperatures could be more significant than when no heat is applied. Further refinements could improve the accuracy of the model to increase its validity in a wider temperature range.
Titanium Dioxide Nanotubes as Solid-Phase Extraction Adsorbent for the Determination of Copper in Natural Water Samples
Authors: Bejaoui Kefi Bochra , Bouchmila Imen , Martin Patrick , M’Hamdi Naceur
Published: January 2022

To increase the sensitivity of the analysis method of good copper sample preparation is essential. In this context, an analytical method was developed for sensitive determination of Cu (II) in environmental water samples by using TiO2 nanotubes as a solid-phase extraction absorbent (SPE). Factors affecting the extraction efficiency including the type, volume, concentration, and flow rate of the elution solvent, the mass of the adsorbent, and the volume, pH, and flow rate of the sample were evaluated and optimized. TiO2 nanotubes exhibited their good enrichment capacity for Cu (II) (~98%). Under optimal conditions, the method of the analysis showed good linearity in the range of 0–22 mg L−1 (R2 > 0.99), satisfactory repeatability (relative standard deviation: RSD was 3.16, n = 5), and a detection limit of about 32.5 ng mL−1. The proposed method was applied to real water samples, and the achieved recoveries were above 95%, showing minimal matrix effect and the robustness of the optimized SPE method.
Diagnosis and Treatment of Primary Inflammatory Choriocapillaropathies (PICCPs): A Comprehensive Overview
Authors: Papasavvas Ioannis , Herbort Carl P.
Published: January 2022

Purpose: Primary inflammatory choriocapillaropathies (PICCPs) belong to a group of intraocular inflammatory diseases with the common characteristic of inflammatory choriocapillaris hypo- or non-perfusion as the main clinicopathological mechanism. The purpose of our article is to describe clinical characteristics and multimodal imaging, that can help the diagnosis and treatment of PICCPs. Methods: Narrative review with multimodal imaging analysis. Results: Choriocapillaris non-perfusion can affect the end-choriocappilaries, at the benign end of the PICCP spectrum (MEWDS), to larger choriocapillaris vessels or precapillary vessels at the origin of more severe forms such as acute posterior multifocal placoid pigment epitheliopathy (APMPPE), idiopathic multifocal choroiditis (MFC) and Serpiginous Choroiditis (SC). Diagnosis is mostly based on multimodal imaging and especially on indocyanine green angiography (ICGA), fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT)/OCT-angiography (OCT-A). ICGA shows the typical pattern of patchy lobular hypofluorescence reflecting hypo- or non-perfusion of the choriocapillaris that can also take the aspect of geographic areas in the more severe forms. Treatment depends on the severity of the disease and goes from observation in MEWDS and some mild cases of APMPPE, to oral corticosteroid and/or immunomodulator agents in the more severe conditions of APMPPE and MFC and SC cases. Close multimodal monitoring is crucial in order to introduce or adjust treatment. Conclusion: PICCPs are resulting from one common clinicopathological mechanism, inflammatory choriocapillaris hypo- or non-perfusion. ICGA findings are essential for the diagnosis and follow-up of PICCPs, but non-invasive methods such as FAF and SD-OCT/OCT-A also have their role especially in follow-up of the diseases. Treatment should be individualized according to the pathology and the evolution of lesions.
Sludge Derived Carbon Modified Anode in Microbial Fuel Cell for Performance Improvement and Microbial Community Dynamics
Authors: Zhu Kaili , Xu Yihu , Yang Xiao , Fu Wencai , Dang Wenhao , Yuan Jinxia , Wang Zhiwei
Published: January 2022

The conversion of activated sludge into high value-added materials, such as sludge carbon (SC), has attracted increasing attention because of its potential for various applications. In this study, the effect of SC carbonized at temperatures of 600, 800, 1000, and 1200 °C on the anode performance of microbial fuel cells and its mechanism are discussed. A pyrolysis temperature of 1000 °C for the loaded electrode (SC1000/CC) generated a maximum areal power density of 2.165 ± 0.021 W·m−2 and a current density of 5.985 ± 0.015 A·m−2, which is 3.017- and 2.992-fold that of the CC anode. The addition of SC improves microbial activity, optimizes microbial community structure, promotes the expression of c-type cytochromes, and is conducive to the formation of electroactive biofilms. This study not only describes a technique for the preparation of high-performance and low-cost anodes, but also sheds some light on the rational utilization of waste resources such as aerobic activated sludge.
Surface-Sensing Principle of Microprobe System for Micro-Scale Coordinate Metrology: A Review
Authors: Michihata Masaki
Published: January 2022

Micro-coordinate measuring machines (micro-CMMs) for measuring microcomponents require a probe system with a probe tip diameter of several tens to several hundreds of micrometers. Scale effects work for such a small probe tip, i.e., the probe tip tends to stick on the measurement surface via surface adhesion forces. These surface adhesion forces significantly deteriorate probing resolution or repeatability. Therefore, to realize micro-CMMs, many researchers have proposed microprobe systems that use various surface-sensing principles compared with conventional CMM probes. In this review, the surface-sensing principles of microprobe systems were the focus, and the characteristics were reviewed. First, the proposed microprobe systems were summarized, and the probe performance trends were identified. Then, the individual microprobe system with different sensing principles was described to clarify the performance of each sensing principle. By comprehensively summarizing multiple types of probe systems and discussing their characteristics, this study contributed to identifying the performance limitations of the proposed micro-probe system. Accordingly, the future development of micro-CMMs probes is discussed.
A Review of the Effects of Olive Oil-Cooking on Phenolic Compounds
Authors: Ambra Roberto , Lucchetti Sabrina , Pastore Gianni
Published: January 2022

The fate of phenolic compounds in oil and food during cooking vary according to the type of cooking. From a nutritional point of view, reviews largely suggest a preference for using extra-virgin olive oil at a low temperature for a short time, except for frying and microwaving, for which there appears to be no significant advantages compared to olive oil. However, due to the poorly pertinent use of terminology, the different protocols adopted in studies aimed at the same objective, the different type and quality of oils used in experiments, and the different quality and quantity of PC present in the used oils and in the studied vegetables, the evidence available is mainly contradictory. This review tries to reanalyse the main experimental reports on the fate, accessibility and bioavailability of phenolic compounds in cooking oils and cooked vegetables, by considering different cooking techniques and types of oil and foods, and distinguishing experimental findings obtained using oil alone from those in combination with vegetables. The re-analysis indicates that incomplete and contradictory observations have been published in the last few years and suggests that further research is necessary to clarify the impact of cooking techniques on the phenolic compounds in oil and vegetables during cooking, especially when considering their nutritional properties.
Impact of a Shorter Brine Soaking Time on Nutrient Bioaccessibility and Peptide Formation in 30-Months-Ripened Parmigiano Reggiano Cheese
Authors: Di Nunzio Mattia , Loffi Cecilia , Chiarello Elena , Dellafiora Luca , Picone Gianfranco , Antonelli Giorgia , Di Gregorio Clarissa , Capozzi Francesco , Tedeschi Tullia , Galaverna Gianni , Bordoni Alessandra
Published: January 2022

Reducing the salt content in food is an important nutritional strategy for decreasing the risk of diet-related diseases. This strategy is particularly effective when applied to highly appreciated food having good nutritional characteristics, if it does not impact either upon sensory or nutritional properties of the final product. This work aimed at evaluating if the reduction of salt content by decreasing the brine soaking time modifies fatty acid and protein bioaccessibility and bioactive peptide formation in a 30-month-ripened Parmigiano Reggiano cheese (PRC). Hence, conventional and hyposodic PRC underwent in vitro static gastrointestinal digestion, and fatty acid and protein bioaccessibility were assessed. The release of peptide sequences during digestion was followed by LC–HRMS, and bioactive peptides were identified using a bioinformatic approach. At the end of digestion, fatty acid and protein bioaccessibility were similar in conventional and hyposodic PRC, but most of the bioactive peptides, mainly the ACE-inhibitors, were present in higher concentrations in the low-salt cheese. Considering that the sensory profiles were already evaluated as remarkably similar in conventional and hyposodic PRC, our results confirmed that shortening brine soaking time represents a promising strategy to reduce salt content in PRC.
Comparative Study between Curcumin and Nanocurcumin Loaded PLGA on Colon Carcinogenesis Induced Mice
Authors: Elbassiouni Farida , El-Kholy Wafaa , Elhabibi El-Sayed , Albogami Sarah , Fayad Eman
Published: January 2022

Colorectal cancer is the third most common cancer. Because curcumin (CUR) has anti-inflammatory and anticancer properties, research has been undertaken to indicate that nanocurcumin compounds can be used to treat a variety of cancers. CUR in nanoform has been found to have a stronger effect than conventional CUR. The purpose of this study was to show that CUR-loaded poly lactic-co-glycolic acid nanoparticles (PLGA) (CUR-loaded PLGA) have anti-inflammatory and anticancer effects on colon carcinogenesis in male dimethyl hydrazine (DMH) mice as a comparative study between the nanoform of curcumin and normal curcumin, focusing on the anticancer effect of nanocurcumin. Mice were separated into six groups: No treatment was given to Group I (negative Group-I). Group II was treated with CUR. Group III was treated with CUR-loaded PLGA. Group IV was treated with DMH. Group V received DMH and curcumin. Group VI received DMH and CUR-loaded PLGA. At the conclusion of the trial, the animals were slain (6 weeks). Inflammatory indicators and vascular endothelial growth factor (VEGF) levels all changed significantly in this study, as the following inflammatory markers as TNF showed percent of change compared to the DMH group. Recovery percentage for Groups V and VI, respectively, were 9.18 and 55.31%. In addition, IL1 was 7.45 and 50.37% for Groups V and VI, respectively. The results of IL6 were 4.86 and 25.79% for Groups V and VI, respectively. The vascular endothelial growth factor (VEGF) recovery percent was 16.98 and 45.12% for Groups V and VI, respectively. Following the effect of DMH on colon mucosa shape, the researchers looked at the effect of CUR-loaded PLGA on colon histology. It was shown that CUR-loaded PLGA affects the cell cycle and PCNA expression. We conclude that nanocurcumin is an important anti-inflammatory and cancer-fighting agent.
The Effects of Stresses and Interfaces on Texture Transformation in Silver Thin Films
Authors: Dang Nhat Minh , Wang Zhao-Ying , Lin Chi-Hang , Lin Ming-Tzer
Published: January 2022

Thin metal films are critical elements in nano- and micro-fabricated technologies. The texture orientation of thin films has a significant effect on applied devices. For Face-Centered Cubic (FCC) metal thin films, when the critical thickness is reached, the texture orientation can transform from (111) to (100) based on the model related to the balance between interfacial energy and strain energy. This research focused on the texture transformation of thin films under two conditions: (1) with or without an adhesion layer in the thin film and (2) with or without initial stress applied through a four-point bending load. In the experiment, two samples (silicon/silver and silicon/titanium/silver) were used to apply different initial stress/strain values and different annealing times. After annealing, an X-ray Diffractometer (XRD) was used to ascertain the preferred orientation of the thin films and the percentage of (111) and (100). Finally, Electron Back-Scattered Diffraction (EBSD) was used to observe the grain size of the thin films. The results showed that, regardless of the existence of an adhesion layer, texture transformation occurred, and this was relatively significant with Ti adhesion layers. Further, the initial stress was found to be small compared to the internal stress; thus, the initial stress imposed in the tests in this research was not significantly influenced by the texture transformation.
Investigation of an Autochthonous Outbreak of Bovine Besnoitiosis in Northwestern Sicily
Authors: Neve Veronica Cristina , Coltraro Miriana , Stamilla Alessandro , Spadola Filippo , Puleio Roberto , Loria Guido Ruggero , Antoci Francesco , Cascone Giuseppe , Salina Felice
Published: January 2022

Bovine besnoitiosis is a parasitic disease caused by the protozoan Besnoitia besnoiti, leading to infertility in bulls and abortions in cows. In Italy, it is considered an emerging disease, recently introduced by the importation of animals from Spain and France. In the last decade, many outbreaks have been reported and confirmed in native cattle, mostly in northern and central Italy. This study reports on an autochthonous outbreak of bovine besnoitiosis in two nearby farms located in northwestern Sicily. A 15-month-old Limousine bull born on the farm showed typical clinical signs of the chronic disease phase, such as edema of the scrotum with subsequent hyperkeratosis associated with eschars and thickening of the skin. A histopathological examination revealed the presence of Besnoitia tissue cysts containing bradyzoites in the eyes, tendons, testicles, dermis, and nictitating membrane. A serological investigation using a commercial ELISA kit revealed a high seroprevalence of the antibody anti-B. besnoiti (79.2% for the farms in this study). Clinical disease showed low prevalence (1.5%) despite the high seroprevalence of specific antibodies in the herd, confirming that bovine besnoitiosis is an emergent endemic pathogen in Sicily, but its clinical behavior still remains sporadic.
Comparison of Young’s Modulus of Continuous and Aligned Lignocellulosic Jute and Mallow Fibers Reinforced Polyester Composites Determined Both Experimentally and from Theoretical Prediction Models
Authors: Ribeiro Maurício , Pinheiro Miriane , Rodrigues Jean , Ramos Roberto , Corrêa Alessandro , Monteiro Sérgio , da Silva Alisson , Candido Verônica
Published: January 2022

Mechanical properties of composites reinforced with lignocellulosic fibers have been researched in recent decades. Jute and mallow fibers are reinforcement alternatives, as they can contribute to increase the mechanical strength of composite materials. The present work aims to predict the Young’s modulus with application of continuous and aligned lignocellulosic fibers to be applied as reinforcement in polyester matrix. Fibers were manually separated and then arranged and aligned in the polyester matrix. Composites with addition 5, 15, and 25 vol% jute and mallow fibers were produced by vacuum-assisted hand lay-up/vaccum-bagging procedure. Samples were tested in tensile and the tensile strength, elasticity modulus, and deformation were determined. Results showed that the intrinsic Young’s modulus of the fibers was set at values around 17.95 and 11.72 GPa for jute and mallow fibers, respectively. Statistical analysis showed that composites reinforced with 15 and 25 vol% jute and mallow presented the highest values of tensile strength and Young’s modulus. The incorporation of 25 vol% of jute and mallow fibers increased the matrix Young’s modulus by 534% and 353%, respectively, effectively stiffening the composite material. Prediction models presented similar values for the Young’s modulus, showing that jute and mallow fibers might be used as potential reinforcement of polymeric matrices
Analysis of Metrological Quality and Mechanical Properties of Models Manufactured with Photo-Curing PolyJet Matrix Technology for Medical Applications
Authors: Kozior Tomasz , Bochnia Jerzy , Gogolewski Damian , Zmarzły Paweł , Rudnik Mateusz , Szot Wiktor , Szczygieł Paweł , Musiałek Mateusz
Published: January 2022

This paper presents the metrological quality and mechanical properties of models in the form of hook holders manufactured from MED610 polymer material using PolyJet Matrix (PJM) technology. Measurements in the dimensional and shape analysis were made using the optical method with a microscope. The mechanical test was estimated by static tensile testing of the fabricated parts. A comprehensive approach to both the analysis of test results based on standardized samples and real hook models makes the presented results of great scientific and engineering value and creates the possibility of practical use in the medical industry, which has not been so comprehensively presented in the currently published research papers. Analyzing the results of measurements of the geometrical characteristics of the elements, it can be concluded that the PolyJet Matrix 3D printing technology has demonstrated a high level of precision in manufacturing the prototype parts. The static tensile test of samples, taking into account the printing directions, showed a high anisotropy of mechanical properties. The results of both strength and simulation tests indicate that it is necessary to assume a relatively high safety factor, the value of which depends on the direction of printing, which, in the case of such a responsible medical application, is very important.
Using Unoccupied Aerial Vehicles (UAVs) to Map Seagrass Cover from Sentinel-2 Imagery
Authors: Carpenter Stephen , Byfield Val , Felgate Stacey L. , Price David M. , Andrade Valdemar , Cobb Eliceo , Strong James , Lichtschlag Anna , Brittain Hannah , Barry Christopher , Fitch Alice , Young Arlene , Sanders Richard , Evans Claire
Published: January 2022

Seagrass habitats are ecologically valuable and play an important role in sequestering and storing carbon. There is, thus, a need to estimate seagrass percentage cover in diverse environments in support of climate change mitigation, marine spatial planning and coastal zone management. In situ approaches are accurate but time-consuming, expensive and may not represent the larger spatial units collected by satellite imaging. Hence, there is a need for a consistent methodology that uses accurate point-based field surveys to deliver high-quality mapping of percentage seagrass cover at large spatial scales. Here, we develop a three-step approach that combines in situ (quadrats), aerial (unoccupied aerial vehicle—UAV) and satellite data to map percentage seagrass cover at Turneffe Atoll, Belize, the largest atoll in the northern hemisphere. First, the optical bands of four UAV images were used to calculate seagrass cover, in combination with in situ data. The seagrass cover calculated from the UAV was then used to develop training and validation datasets to estimate seagrass cover in Sentinel-2 pixels. Next, non-seagrass areas were identified in the Sentinel-2 data and removed by object-based classification, followed by a pixel-based regression to calculate seagrass percentage cover. Using this approach, percentage seagrass cover was mapped using UAVs (R2 = 0.91 between observed and mapped distributions) and using Sentinel-2 data (R2 = 0.73). This work provides the first openly available and explorable map of seagrass percentage cover across Turneffe Atoll, where we estimate approximately 242 km2 of seagrass above 10% cover is located. We estimate that this approach offers 30 times more data for training satellite data than traditional methods, therefore presenting a substantial reduction in cost-per-point for data. Furthermore, the increase in data helps deliver a high-quality seagrass cover map, suitable for resolving trends of deteriorating, stable or recovering seagrass environments at 10 m2 resolution to underpin evidence-based management and conservation of seagrass.
Occluded Apple Fruit Detection and Localization with a Frustum-Based Point-Cloud-Processing Approach for Robotic Harvesting
Authors: Li Tao , Feng Qingchun , Qiu Quan , Xie Feng , Zhao Chunjiang
Published: January 2022

Precise localization of occluded fruits is crucial and challenging for robotic harvesting in orchards. Occlusions from leaves, branches, and other fruits make the point cloud acquired from Red Green Blue Depth (RGBD) cameras incomplete. Moreover, an insufficient filling rate and noise on depth images of RGBD cameras usually happen in the shade from occlusions, leading to the distortion and fragmentation of the point cloud. These challenges bring difficulties to position locating and size estimation of fruit for robotic harvesting. In this paper, a novel 3D fruit localization method is proposed based on a deep learning segmentation network and a new frustum-based point-cloud-processing method. A one-stage deep learning segmentation network is presented to locate apple fruits on RGB images. With the outputs of masks and 2D bounding boxes, a 3D viewing frustum was constructed to estimate the depth of the fruit center. By the estimation of centroid coordinates, a position and size estimation approach is proposed for partially occluded fruits to determine the approaching pose for robotic grippers. Experiments in orchards were performed, and the results demonstrated the effectiveness of the proposed method. According to 300 testing samples, with the proposed method, the median error and mean error of fruits’ locations can be reduced by 59% and 43%, compared to the conventional method. Furthermore, the approaching direction vectors can be correctly estimated.
Study on High-Resolution Suspended Sediment Distribution under the Influence of Coastal Zone Engineering in the Yangtze River Mouth, China
Authors: Cai Lina , Chen Songyu , Yan Xiaojun , Bai Yan , Bu Juan
Published: January 2022

In this study, we analyzed the influence of coastal zone engineering on suspended sediment concentration (SSC) in the Yangtze River mouth based on HY-1C and Chinese GaoFen (GF) satellite data. The results show that: (1) SSC in the Yangtze River mouth is mainly in the range of 200–1300 mg/L, which changes due to natural factors as well as coastal zone engineering; (2) The sand blocking engineering effectively protects the channel from siltation, and SSC in the central line of the channel is 100–300 mg/L lower than that near the dikes in the north and south; (3) Qingcaosha Reservoir plays a stabilizing role in the hydrodynamic force, promoting the deposition of suspended matter, so that the water in the reservoir is clear. SSC inside the Qingcaosha Reservoir, located in the center of the estuary, is 100–500 mg/L lower than the high SSC water outside the reservoir; (4) The bridges interact with the current, facilitating the transport of local sediment, resulting in the increase in SSC downstream of these bridges, and obvious vortexes appear with the length up to nearly 2400 m; and (5) Corresponding protection and development suggestions were put forward as follows. A linear array of wind power plants can be built near and parallel to dikes and leading jetties; to increase the depth of the southeast end of the reservoir; and the location of the bridge should be selected in the place of river where siltation is easy. This study aimed to study the SSC distribution under the complex impact of coastal zone engineering with satellite and to provide possible improvement suggestions.
A Coupled BRDF CO2 Retrieval Method for the GF-5 GMI and Improvements in the Correction of Atmospheric Scattering
Authors: Ye Hanhan , Shi Hailiang , Li Chao , Wang Xianhua , Xiong Wei , An Yuan , Wang Yue , Liu Liangchen
Published: January 2022

The Greenhouse Gases Monitoring Instrument (GMI), on board the Chinese Gaofen-5 (GF-5) satellite, provides rich observation data for the global remote sensing of atmospheric CO2. To meet the high-precision satellite retrieval needs of atmospheric CO2, this paper designs a coupled bidirectional reflectance distribution function (BRDF) CO2 retrieval (CBCR) method, which describes the surface reflectance characteristics by the BRDF, corrects for atmospheric scattering based on full physics retrieval theory, and ensures the stable retrieval of multiple parameters and atmospheric CO2 by enriching prior constraints. Theoretical analysis shows that the influence of atmospheric scattering induced by the surface bidirectional reflectance characteristics is significantly related to the aerosol optical depth (AOD), solar zenith angle (SZA), and viewing zenith angle (VZA). The validation of GMI CO2 retrievals shows that the CBCR method significantly reduced the influence of the surface bidirectional reflectance characteristics under high AOD and high SZA conditions, decreased the atmospheric CO2 retrieval error from 0.58 ± 5.64 ppm to −1.33 ± 3.13 ppm, and increased the correlation with the temporal variation of actual atmospheric CO2 from 34.7 to 76.8%. Our CBCR method can correct the influence of atmospheric scattering induced by the surface bidirectional reflectance characteristics on atmospheric CO2 retrieval, and this work demonstrates that describing the surface reflectance characteristics by using BRDF is a promising idea in the field of satellite CO2 retrievals.
Evaluating the Associations between Forward Collision Warning Severity and Driving Context
Authors: Seaman Sean , Gershon Pnina , Angell Linda , Mehler Bruce , Reimer Bryan
Published: January 2022

Forward collision warning (FCW) systems typically employ forward sensing technologies to identify possible forward collisions and provide an alert to the driver in the event they have not recognized a threat. These systems have demonstrated safety benefits. However, because the base rate of collisions is low, sensitive FCW systems can provide a high rate of alarms in situations with no or low probability of collision, which may negatively impact driver responsiveness and satisfaction. We examined over 2000 naturally occurring FCWs in two modern vehicles as a part of a naturalistic driving study investigation into advanced vehicle technologies. Analysts used cabin and forward camera footage, as well as environmental characteristics, to judge the likelihood of a crash during each alert, which were used to model the likelihood of an alert representing a possible collision. Only nine FCWs were considered “crash possible and imminent”. Road-type, speed, traffic density, and deceleration profiles distinguished between alert severity. Modeling outcomes provide clues for reducing nuisance and false alerts, and the method of using subjective video annotation combined with vehicle kinematics shows promise for investigating FCW alerts in the real world.
A Simple Method for the Determination of Polyphenolic Compounds from Grapevine Leaves
Authors: Štambuk Petra , Anić Marina , Huzanić Nera , Preiner Darko , Karoglan Marko , Kontić Jasminka , Tomaz Ivana
Published: January 2022

Grapevine leaves are photosynthetically the most active green organs providing carbohydrates that are of utmost importance for the regular vine’s metabolism and growth. Moreover, leaves are the pioneers of fungal infections caused by B. cinerea, E. necator, and P. viticola. Plant response to these microorganisms mostly depends on the content and composition of phenolic compounds abundantly found in the leaf’s outer tissues (epidermis, cuticle, trichomes). In order to obtain a satisfactory quantity of phenolic compounds, an experiment was conducted towards optimizing a solid–liquid extraction method. Variables were as follows: the type of organic solvent, the sample weight, the extraction temperature, and the extraction time. The optimal conditions were obtained by applying the response surface methodology. Therefore, by using acetonitrile as the organic solvent, conducting a single-step extraction at the temperature of 48 °C during the time period of 2 h and 25 min with a solid-to-solvent ratio of 1:56 g mL−1 (178 mg of leaves powder and 10 mL of extraction solvent) the optimal content of phenolic compounds was obtained. This protocol is reliable, fast, and relatively easy to perform for the determination of the abovementioned compounds.
Efficient Stochastic Computing FIR Filtering Using Sigma-Delta Modulated Signals
Authors: Temenos Nikos , Vlachos Anastasis , Sotiriadis Paul P.
Published: January 2022

This work presents a soft-filtering digital signal processing architecture based on sigma-delta modulators and stochastic computing. A sigma-delta modulator converts the input high-resolution signal to a single-bit stream enabling filtering structures to be realized using stochastic computing’s negligible-area multipliers. Simulation in the spectral domain demonstrates the filter’s proper operation and its roll-off behavior, as well as the signal-to-noise ratio improvement using the sigma-delta modulator, compared to typical stochastic computing filter realizations. The proposed architecture’s hardware advantages are showcased with synthesis results for two FIR filters using FPGA and synopsys tools, while comparisons with standard stochastic computing-based hardware realizations, as well as with conventional binary ones, demonstrate its efficacy.
Effect of Climate Change and Anthropogenic Activities on Streamflow Indicators in a Tropical River Basin in Southern China
Authors: Xu Fei , Zhao Lingling , Niu Cunwen , Qiu Yaqin
Published: January 2022

Climate change and anthropogenic activities are the two main driving elements influencing changes in streamflow. Previous studies mainly focused on the impacts of climate change and anthropogenic activities on annual mean streamflow (AMS), ignoring annual maximum streamflow (Amax) and annual minimum streamflow (Amin). On the other hand, most previous studies attributed the impacts of climate change and anthropogenic activities synoptically. However, the separate influence mechanism among climatic variables, such as precipitation, temperature, sunshine duration change, direct human activities, and land use cover change, needs further analysis. We used the Water and Energy transfer Processes in Large River basin (WEP–L) model to quantify the impacts of climatic variables (precipitation, temperature, and sunshine duration) and anthropogenic activities (land use cover change (LUCC) and direct human activities (DHAs)) on streamflow in the Caojiang River Basin (CRB) with a tropical climate. The results indicate that anthropogenic activities play a major role in streamflow indictor variation. Of the investigated factors related to climate change, precipitation showed the greatest impact on streamflow variation. Notably, DHA contributed the most to the variation of the three streamflow indictors, followed by precipitation, temperature, and sunshine duration, while LUCC had a much lower impact on streamflow variation. This study investigated the response of different streamflow indicators (AMS, Amax, and Amin) to climate change and anthropogenic activities, and it is of value to watershed resource planning and management.
Environmental and Economic Impacts of the Grand Ethiopian Renaissance Dam in Africa
Authors: Kamara Ahmed , Ahmed Mohamed , Benavides Arturo
Published: January 2022

A multidisciplinary study was conducted to investigate the environmental and economic impact of the Grand Ethiopian Renaissance Dam (GERD). Focusing on Egypt, we estimate projected losses in Egypt’s annual water allocation from the Blue Nile under the 3, 7, and 10-year GERD reservoir filling scenarios, which are part of an array of scenarios currently under consideration. We then examine the resultant losses in Egypt’s agricultural land and the corresponding impact on selected macroeconomic variables relative to a baseline (no GERD) scenario. For the 3-year filling period, in particular, we estimate projected losses in Egypt’s annual water allocation to be 51.29 ± 2.62%. This translates into annual losses of agricultural land of 52.75 ± 2.44% relative to the baseline, with a resultant decline in food production of 38.47 ± 2.18% and an overall decline in agricultural sector output by 17.51 ± 0.99%. This contributes to a rise in the national unemployment rate of 11.24 ± 1.77 percentage points above the baseline. Moreover, we estimate projected annual losses in real Gross Domestic Product (GDP) per capita to be 8.02 ± 0.45% relative to the baseline, which translates into an annual loss in real GDP of $26.30 ± 2.81 billion and a loss in welfare of 12.83 ± 0.73% annually, relative to the baseline.
Taking a Health Perspective on Roller Derby: A Qualitative Exploration of Women’s Experiences
Authors: Scullion Jane , Bulley Cathy
Published: January 2022

Although far fewer women exercise regularly than men, one women-dominated sport growing in popularity internationally is roller derby. A limited number of predominantly US-based and qualitative studies have explored roller derby. This Scotland-based qualitative study explored reasons for women starting, continuing, and stopping participation in roller derby in order to inform people involved in promoting physical activity for health benefits. Semi-structured interviews with six participants from a Scottish women’s roller derby league were recorded and transcribed verbatim. Data analysis using Interpretative Phenomenological Analysis generated five super-ordinate themes. Most participants learned about roller derby from watching the sport on film, attending a bout (game), or word of mouth. The main motivators and benefits of participating in this sport were found to be challenge, enjoyment, increased confidence, health benefits, and motivation to exercise. Participants were empowered by involvement and motivated by community, team spirit, and support to develop. Despite high commitment, some women could not sustain team involvement due to barriers such as injury, changing life roles, and conflicting commitments—a lack of support was described when this happened. Greater inclusivity is needed to enable changing levels of participation as women’s commitments change, to facilitate ongoing health benefits and inspire others.
The rationale for the algorithm of comprehensive digital diagnosis of patients with temporomandibular disorders using an intraoral occlusal appliance
Authors: Dubova L. V. , Stupnikov P. A. , Stupnikov А. А. , Burenhcev D. V. , Kharchenko D. A.
Published: January 2022

Relevance. The study aimed to increase the effectiveness of comprehensive diagnosis and treatment of patients with TMD using an intraoral occlusal appliance.Materials and methods. All patients of the main group underwent a digital comprehensive functional examination, including TMJ magnetic resonance imaging, kinesiography, joint vibration analysis, surface myography and electrical stimulation of the masticatory muscles, followed by a bite registration of the optimal mandible position. According to the bite recorder, the models were mounted in the articulator and the intraoral occlusal appliance was fabricated. This occlusal appliance used the first-class lever principle, which acts on the condyle using a force applied to the mesial part of the canine and rests on the distal part of the upper second molar. After the diagnosis and treatment stage using an occlusal appliance, a digital comprehensive functional examinatio n was performed again.Results. Analysis of the digital comprehensive diagnosis data evidenced the restoration of the lower jaw movement, the elimination of intra-articular disorder and the normalization of the dentition functioning as a whole, using TENS appliance and an improved intraoral occlusal appliance (Patent # 273 0995, 26.08.2020) in patients with TMD.Conclusion. Treatment of patients with TMD using an intraoral occlusal appliance, which eliminates condyle compression and dislocation of the articular disc, allows restoring the lower jaw movement and the functioning of the dentition as a whole. Kinesiography at all stages of the prosthodontic treatment allows objectively monitoring the restoration of the mandibular movement pathways, taking into account time inte rvals.