bluuebunny/crossref_metadata_2025 huggingface dataset:
Aging Affects Lower Limb Joint Moments and Muscle Responses to a Split-Belt Treadmill Perturbation
Authors: Yoo Dongyual , An Junmo , Seo Kap-Ho , Lee Beom-Chan
Published: July 2021

Age-related changes cause more fall-related injuries and impede the recoveries by older adults compared to younger adults. This study assessed the lower limb joint moments and muscle responses to split-belt treadmill perturbations in two groups (14 healthy young group [23.36 ± 2.90 years] and 14 healthy older group [70.93 ± 4.36 years]) who performed two trials of unexpected split-belt treadmill perturbations while walking on a programmable split-belt treadmill. A motion capture system quantified the lower limb joint moments, and a wireless electromyography system recorded the lower limb muscle responses. The compensatory limb's (i.e., the tripped limb's contralateral side) joint moments and muscle responses were computed during the pre-perturbation period (the five gait cycles before the onset of a split-belt treadmill perturbation) and the recovery period (from the split-belt treadmill perturbation to the baseline gait relying on the ground reaction forces' profile). Joint moments were assessed by maximum joint moments, and muscle responses were quantified by the normalization (%) and co-contraction index (CCI). Joint moments and muscle responses of the compensatory limb during the recovery period were significantly higher for the YG than the OG, and joint moments (e.g., knee flexion and extension and hip flexion moments) and muscle responses during the recovery period were higher compared to the pre-perturbation period for both groups. For CCI, the older group showed significantly higher co-contraction for biceps femoris/rectus femoris muscles than the young group during the recovery period. For both groups, co-contraction for biceps femoris/rectus femoris muscles was higher during the pre-perturbation period than the recovery period. The study confirmed that older adults compensated for muscle weakness by using lower joint moments and muscle activations and increasing muscle co-contractions to recover balance after split-belt treadmill perturbations. A better understanding of the recovery mechanisms of older adults who train on fall-inducing systems could improve therapeutic regimens.
A Framework for Addressing the Twin Challenges of COVID-19 and Climate Change for Sustainable Agriculture and Food Security in South Asia
Authors: Rasul Golam
Published: July 2021

Climate change has begun to ravage agriculture and threaten food security in many parts of the world. The novel coronavirus pandemic (COVID-19) has further disrupted agricultural activities and supply chains and has become a serious threat for public health. Like in many developing countries, South Asian farmers are now facing the double challenge of addressing the impacts of a changing climate and managing the disruptions caused by COVID-19. Despite growing concern, there is limited understanding of how climate change, public health, and COVID-19 interact, and of the possible pathways to achieving a climate-friendly recovery from COVID-19 to achieve food and nutrition security. In view of this, this paper explores the multifaceted challenges that farmers are now facing in South Asia due to climate change and the disruption caused by COVID-19 from the agricultural and food security lens. The analysis reveals that the complex interactions of COVID-19 and climate change have impacted all dimensions of food security. These interlinkages demand an integrated approach in dealing with food, public health, and climate change to harness synergies and minimize trade-offs between food production, public health, and climate mitigation. I present a framework to address the immediate challenge of COVID-19 and the longer-term challenge of anthropogenic climate change. Key elements of the framework include the strengthening health sector response capacities, strengthening of local and regional food systems, making agriculture resilient to pandemics, adopting flexible and smart approaches—including the implementation of climate-smart agricultural interventions on different scales, promotion of appropriate research and innovation, and the integration of short-term support to address the challenges of COVID-19 to build long-term productivity, and resilience of food systems by investing on natural capital. This framework would enable policy makers to choose the appropriate policy responses at different scales, to address these twin challenges of COVID-19 and climate change.
Characterization of the Impact of Density Gradient Centrifugation on the Profile of the Pig Sperm Transcriptome by RNA-Seq
Authors: Lian Yu , Gòdia Marta , Castello Anna , Rodriguez-Gil Joan Enric , Balasch Sam , Sanchez Armand , Clop Alex
Published: July 2021

RNA-Seq data from human semen suggests that the study of the sperm transcriptome requires the previous elimination from the ejaculates of somatic cells carrying a larger load of RNA. Semen purification is also carried to study the sperm transcriptome in other species including swine and it is often done by density gradient centrifugation to obtain viable spermatozoa from fresh ejaculates or artificial insemination doses, thereby limiting the throughput and remoteness of the samples that can be processed in one study. The aim of this work was to evaluate the impact of purification with density gradient centrifugation by BoviPureTM on porcine sperm. Four boar ejaculates were purified with BoviPureTM and their transcriptome sequenced by RNA-Seq was compared with the RNA-Seq profiles of their paired non-purified sample. Seven thousand five hundred and nineteen protein coding genes were identified. Correlation, cluster, and principal component analysis indicated high—although not complete—similarity between the purified and the paired non-purified ejaculates. 372 genes displayed differentially abundant RNA levels between treatments. Most of these genes had lower abundances after purification and were mostly related to translation, transcription and metabolic processes. We detected a significant change in the proportion of genes of epididymal origin within the differentially abundant genes (1.3%) when compared with the catalog of unaltered genes (0.2%). In contrast, the proportion of testis-specific genes was higher in the group of unaltered genes (4%) when compared to the list of differentially abundant genes (0%). No proportion differences were identified for prostate, white blood, lymph node, tonsil, duodenum, skeletal muscle, liver, and mammary gland. Altogether, these results suggest that the purification impacts on the RNA levels of a small number of genes which are most likely caused by the removal of epididymal epithelial cells but also premature germinal cells, immature or abnormal spermatozoa or seminal exosomes with a distinct load of RNAs.
A Combined Flow Cytometric Semen Analysis and miRNA Profiling as a Tool to Discriminate Between High- and Low-Fertility Bulls
Authors: Turri Federica , Capra Emanuele , Lazzari Barbara , Cremonesi Paola , Stella Alessandra , Pizzi Flavia
Published: July 2021

Predicting bull fertility is one of the main challenges for the dairy breeding industry and artificial insemination (AI) centers. Semen evaluation performed in the AI center is not fully reliable to determine the level of bull fertility. Spermatozoa are rich in active miRNA. Specific sperm-borne miRNAs can be linked to fertility. The aim of our study is to propose a combined flow cytometric analysis and miRNA profiling of semen bulls with different fertility to identify markers that can be potentially used for the prediction of field fertility. Sperm functions were analyzed in frozen-thawed semen doses (CG: control group) and high-quality sperm (HQS) fraction collected from bulls with different field fertility levels (estimated relative conception rate or ERCR) by using advanced techniques, such as the computer-assisted semen analysis system, flow cytometry, and small RNA-sequencing. Fertility groups differ for total and progressive motility and in the abnormality degree of the chromatin structure (P< 0.05). A backward, stepwise, multiple regression analysis was applied to define a model with high relation betweenin vivo(e.g., ERCR) andin vitro(i.e., semen quality and DE-miRNA) fertility data. The analysis produced two models that accounted for more than 78% of the variation of ERCR (CG:R2= 0.88; HQS:R2= 0.78), identifying a suitable combination of parameters useful to predict bull fertility. The predictive equation on CG samples included eight variables: four kinetic parameters and four DNA integrity indicators. For the HQS fraction, the predictive equation included five variables: three kinetic parameters and two DNA integrity indicators. A significant relationship was observed between real and predicted fertility in CG (R2= 0.88) and HQS fraction (R2= 0.82). We identified 15 differentially expressed miRNAs between high- and low-fertility bulls, nine of which are known (miR-2285n, miR-378, miR-423-3p, miR-191, miR-2904, miR-378c, miR-431, miR-486, miR-2478) while the remaining are novel. The multidimensional preference analysis model partially separates bulls according to their fertility, clustering three semen quality variable groups relative to motility, DNA integrity, and viability. A positive association between field fertility, semen quality parameters, and specific miRNAs was revealed. The integrated approach could provide a model for bull selection in AI centers, increasing the reproductive efficiency of livestock.
Sensitivity Analysis of Maximum Circulation of Wake Vortex Encountered by En-Route Aircraft
Authors: Rojas Jose I. , Melgosa Marc , Prats Xavier
Published: July 2021

Wake vortex encounters (WVE) can pose significant hazard for en-route aircraft. We studied the sensitivity of wake vortex (WV) circulation and decay to aircraft mass, altitude, velocity, density, time of catastrophic wake demise event, eddy dissipation rate, wing span, span-wise load factor, and WV core radius. Then, a tool was developed to compute circulations of WV generated/encountered by aircraft en-route, while disregarding unrealistic operational conditions. A comprehensive study is presented for most aircraft in the Base of Aircraft Data version 4.1 for different masses, altitudes, speeds, and separation values between generator and follower aircraft. The maximum WV circulation corresponds to A380-861 as generator: 864 and 840 m2/s at horizontal separation of 3 and 5 NM, respectively. In cruise environment, these WV may descend 1000 ft in 2.6 min and 2000 ft in 6.2 min, while retaining 74% and 49% of their initial strength, respectively. The maximum circulation of WV encountered by aircraft at horizontal separation of 3 NM from an A380-861 is 593, 726, and 745 m2/s, at FL200, FL300, and FL395, respectively. At 5 NM, the circulations decrease down to 578, 708, and 726 m2/s. Our results allow reducing WVE simulations only to critical scenarios, and thus perform more efficient test programs for computing aircraft upsets en-route.
An Analysis of Mushroom Consumption in Hungary in the International Context
Authors: Bringye Bernadett , Fekete-Farkas Maria , Vinogradov Szergej
Published: July 2021

It is hardly an exaggeration to state that producing and consuming mushrooms may provide an answer to several of the challenges facing mankind. This research is related to the UN sustainable development goals relative to different issues. First of all, mushroom production uses agricultural and industrial byproducts as inputs and being labor intensive contributes to the job and income creation for undereducated people in less developed areas. In addition, as mushrooms have high protein content and they are a suitable alternative for meat for populations with a diet lacking in variety; at the same time, they also have the potential for food connoisseurs and consumers who make conscious and educated choices to improve their diet by using healthful and environmentally friendly methods. The nutritional value of mushrooms means that consumption could be an important supplementary therapy for several illnesses. The key issue of sector development is the increasing demand. In order to address this, investigation and research related to consumer behavior is needed. The aim of this research was to explore the dimensions of Hungarian mushroom consumer behavior and to segment Hungarian consumers. An online questionnaire survey was conducted between December 2019 and February 2020 and the final sample of 1768 respondents was considered for the purposes of analysis. Exploratory factor analysis was used to identify groups of correlating variables describing mushroom consumption. The authors identified four dimensions of Hungarian mushroom consumer behavior: (1) medicinal and functional properties, (2) consumption for enjoyment, (3) supplementary food source, and (4) negative assessment of the product range. Using cluster analysis, three consumer groups were identified: (1) health-conscious consumers, (2) indifferent consumers, and (3) average consumers. The research results indicated that consumers’ sociodemographic characteristics (age, educational level, marital status, and place of residence) have a significant impact on mushroom consumption behavior. The results of this paper can have implications for policy makers and business management in diversifying their production and selecting marketing tools.
Genome-Wide Investigation of Spliceosomal SM/LSM Genes in Wheat (Triticum aestivum L.) and Its Progenitors
Authors: Gao Ruiting , Su Ning , Pan Wenqiu , Bao Qiaoyu , Li Zhen , Nie Xiaojun , Tong Wei , Song Weining
Published: July 2021

The SSM/SLSM (spliceosomal Smith (SM)/SM-like (LSM)) genes are the central components of the spliceosome in eukaryotes, which play an important role in regulating RNA splicing, participating in diverse biological processes. Although it has been detected in Arabidopsis and rice etc. plants, the members and significance of the SSM/SLSM gene family in wheat are still not reported. In this study, we identified the SSM/SLSM genes in wheat and its progenitors at genome-scale, where 57 SSM/SLSM genes were identified in wheat, together with 41, 17and 19 found in Triticum dicoccoides, Triticum urartu, and Aegilops tauschii. Furthermore, their phylogenetic relationship, gene structures, conserved motifs, and cis-regulatory elements were systematically analyzed. By synteny analysis, good collinearity of SSM/SLSM genes was found among bread wheat and its progenitors’ genomes, and the distribution of SMD2 genes in wheat chromosome 5A, 4B and 4D located in the 4AL-5AL-7BS chromosome model, due to the translocation. Then, the positively selected genes were further investigated based on the non-synonymous to synonymous (dN/dS) analysis of the orthologous pairs. Finally, the expression profiles of the SSM/SLSM genes were detected using RNA-seq datasets, and eight stress-responsive candidate genes were selected to validate their expression through qPCR (real-time quantitative polymerase chain reaction). According to the co-expression network analysis, the correlation between the LSM7-7A gene and related genes was illustrated through Gene Ontology (GO) enrichment analysis. Furthermore, the LSM7-7A gene was related to the Arabidopsis homologous salt tolerance gene RCY1. This investigation systematically identified the complete candidates of SSM/SLSM genes and their characters in wheat and its progenitors, and provided clues to a better understanding of their contribution during the wheat polyploidy process.
The Influence of Seed Production Environment on Seed Development and Quality of Soybean (Glycine max (L.) Merrill)
Authors: Weerasekara Indika , Sinniah Uma Rani , Namasivayam Parameswari , Nazli Muhamad Hazim , Abdurahman Sharif Azmi , Ghazali Mohd Norsazwan
Published: July 2021

The aim of the study was to determine the effect of seed production environment in Sri Lanka on seed development, maturation, and subsequent seed quality. The experiment was conducted at six production environments, three locations (Mahailluppalama (M1), Polonnaruwa (POL), and Aluttarama (ALU), over two planting cycles (P1, P2). Seed development and maturation, seed and seedling quality characteristics were evaluated at five reproductive (R6, R7, R8, R8 + 5 and R8 + 10) maturity stages. The study infers that production environment at the late reproductive (LR) stage (R6–R8) was critical in determining the seed quality. If the LR stage coincided with cumulative rainfall (RF) over 100 mm or above 75% relative humidity (RH), categorized as wet environment, around 27.5 days was required for the completion of seed maturation compared with only 17.5 days in dry environment. Seed lots from dry environment during LR stage surpassed the minimum quality standards (75% final germination, germination index of 300, germination rate index of 25% per day, seedling vigor index of 2500 and 15 µmol/min/mg FW catalase activity) at maturity stage R7 onwards, while this only occurred at maturity stage R8 for wet environment. A significant negative correlation (r = −0.50 **) was observed between glucose content, antioxidant enzyme activities and germination percentage. In conclusion, the findings provide useful information for the expansion of areas for seed production in Sri Lanka.
Effects of Multivalent BRD Vaccine Treatment and Temperament on Performance and Feeding Behavior Responses to a BVDV1b Challenge in Beef Steers
Authors: Smith Paul , Carstens Gordon , Runyan Chase , Ridpath Julia , Sawyer Jason , Herring Andy
Published: July 2021

This study examined the effects of multivalent respiratory vaccine treatment (VT) and animal temperament classification on feeding behavior traits, feed intake and animal performance in response to a bovine viral diarrhea virus (BVDV) challenge. Nellore–Angus crossbred steers (n = 360; initial body weight (BW) 330 ± 48 kg) were assigned to one of three vaccine treatments: non-vaccinated (NON), modified live (MLV) and killed (KV) regarding respiratory viral pathogens, and inoculated intranasally with the same BVDV1b strain. Cattle temperament categories were based on exit velocity. Overt clinical signs of respiratory disease were not observed, yet the frequency and duration of bunk visit events as well as traditional performance traits decreased (p < 0.01) following BVDV challenge and then rebounded in compensatory fashion. The reduction in dry matter intake (DMI) was less (p < 0.05) for MLV-vaccinated steers, and MLV-vaccinated steers had longer (p < 0.01) durations of bunk visit and meal events and slower (p < 0.01) eating rates compared with KV- and non-vaccinated steers following BVDV challenge. Greater differences in most feeding behavior traits due to VT existed within calm vs. excitable steers. Respiratory vaccination can reduce the sub-clinical feeding behavior and performance effects of BVDV in cattle, and the same impacts may not occur across all temperament categories.
Tackling Virulence of Pseudomonas aeruginosa by the Natural Furanone Sotolon
Authors: Aldawsari Mohammed , Khafagy El-Sayed , Saqr Ahmed , Alalaiwe Ahmed , Abbas Hisham , Shaldam Moataz , Hegazy Wael , Goda Reham
Published: July 2021

The bacterial resistance development due to the incessant administration of antibiotics has led to difficulty in their treatment. Natural adjuvant compounds can be co-administered to hinder the pathogenesis of resistant bacteria. Sotolon is the prevailing aromatic compound that gives fenugreek its typical smell. In the current work, the anti-virulence activities of sotolon on Pseudomonas aeruginosa have been evaluated. P. aeruginosa has been treated with sotolon at sub-minimum inhibitory concentration (MIC), and production of biofilm and other virulence factors were assessed. Moreover, the anti-quorum sensing (QS) activity of sotolon was in-silico evaluated by evaluating the affinity of sotolon to bind to QS receptors, and the expression of QS genes was measured in the presence of sotolon sub-MIC. Furthermore, the sotolon in-vivo capability to protect mice against P. aeruginosa was assessed. Significantly, sotolon decreased the production of bacterial biofilm and virulence factors, the expression of QS genes, and protected mice from P. aeruginosa. Conclusively, the plant natural substance sotolon attenuated the pathogenicity of P. aeruginosa, locating it as a plausible potential therapeutic agent for the treatment of its infections. Sotolon can be used in the treatment of bacterial infections as an alternative or adjuvant to antibiotics to combat their high resistance to antibiotics.
Hypoxia Tolerance Declines with Age in the Absence of Methionine Sulfoxide Reductase (MSR) in Drosophila melanogaster
Authors: Suthakaran Nirthieca , Chandran Sanjana , Iacobelli Michael , Binninger David
Published: July 2021

Unlike the mammalian brain, Drosophila melanogaster can tolerate several hours of hypoxia without any tissue injury by entering a protective coma known as spreading depression. However, when oxygen is reintroduced, there is an increased production of reactive oxygen species (ROS) that causes oxidative damage. Methionine sulfoxide reductase (MSR) acts to restore functionality to oxidized methionine residues. In the present study, we have characterized in vivo effects of MSR deficiency on hypoxia tolerance throughout the lifespan of Drosophila. Flies subjected to sudden hypoxia that lacked MSR activity exhibited a longer recovery time and a reduced ability to survive hypoxic/re-oxygenation stress as they approached senescence. However, when hypoxia was induced slowly, MSR deficient flies recovered significantly quicker throughout their entire adult lifespan. In addition, the wildtype and MSR deficient flies had nearly 100% survival rates throughout their lifespan. Neuroprotective signaling mediated by decreased apoptotic pathway activation, as well as gene reprogramming and metabolic downregulation are possible reasons for why MSR deficient flies have faster recovery time and a higher survival rate upon slow induction of spreading depression. Our data are the first to suggest important roles of MSR and longevity pathways in hypoxia tolerance exhibited by Drosophila.
Dual Mechanisms of Cardiac Action Potential Prolongation by 4-Oxo-Nonenal Increasing the Risk of Arrhythmia; Late Na+ Current Induction and hERG K+ Channel Inhibition
Authors: Choi Seong-Woo , Yin Ming-Zhe , Park Na-Kyeong , Woo Joo-Han , Kim Sung-Joon
Published: July 2021

4-Oxo-nonenal (4-ONE) is an endogenous lipid peroxidation product that is more reactive than 4-hydroxy-nonenal (4-HNE). We previously reported the arrhythmic potential of 4-HNE by suppression of cardiac human Ether-a-go-go Related Gene (hERG) K+ channels with prolonged action potential duration (APD) in cardiomyocytes. Here, we illustrate the higher arrhythmic risk of 4-ONE by modulating the cardiac hNaV1.5 channel currents (INaV). Although the peak amplitude of INaV was not significantly changed by 4-ONE up to 10 μM, the rate of INaV inactivation was slowed, and the late Na+ current (INaL) became larger by 10 μM 4-ONE. The chemical modification of specific residues in hNaV1.5 by 4-ONE was identified using MS-fingerprinting analysis. In addition to the changes in INaV, 4-ONE decreased the delayed rectifier K+ channel currents including the hERG current. The L-type Ca2+ channel current was decreased, whereas its inactivation was slowed by 4-ONE. The APD prolongation by 10 μM of 4-ONE was more prominent than that by 100 μM of 4-HNE. In the computational in silico cardiomyocyte simulation analysis, the changes of INaL by 4-ONE significantly exacerbated the risk of arrhythmia exhibited by the TdP marker, qNet. Our study suggests an arrhythmogenic effect of 4-ONE on cardiac ion channels, especially hNaV1.5.
Metabolic Changes and Oxidative Stress in Diabetic Kidney Disease
Authors: Sakashita Midori , Tanaka Tetsuhiro , Inagi Reiko
Published: July 2021

Diabetic kidney disease (DKD) is a major cause of end-stage kidney disease, and it is crucial to understand the pathophysiology of DKD. The control of blood glucose levels by various glucose-lowering drugs, the common use of inhibitors of the renin–angiotensin system, and the aging of patients with diabetes can alter the disease course of DKD. Moreover, metabolic changes and associated atherosclerosis play a major role in the etiology of DKD. The pathophysiology of DKD is largely attributed to the disruption of various cellular stress responses due to metabolic changes, especially an increase in oxidative stress. Therefore, many antioxidants have been studied as therapeutic agents. Recently, it has been found that NRF2, a master regulator of oxidative stress, plays a major role in the pathogenesis of DKD and bardoxolone methyl, an activator of NRF2, has attracted attention as a drug that increases the estimated glomerular filtration rate in patients with DKD. This review outlines the altered stress responses of cellular organelles in DKD, their involvement in the pathogenesis of DKD, and discusses strategies for developing therapeutic agents, especially bardoxolone methyl.
Suitability of Aerial Photogrammetry for Dump Documentation and Volume Determination in Large Areas
Authors: Kovanič Ľudovít , Blistan Peter , Štroner Martin , Urban Rudolf , Blistanova Monika
Published: July 2021

The study presented in this paper analyses the results of measurements and data processing for documentation and quantification of material in heaps in large areas, where UAVs may no longer be effective due to a large range. Two test heaps were selected from a whole area, where the aim was to confirm the suitability of using the method of digital aerial photogrammetry by manned (crewed) aerial vehicle. For comparison, a commonly used GNSS RTK method was also used. Terrestrial laser scanning was chosen as the control reference method. TLS measurement is a trusted method with high accuracy. The methods were compared with each other through the quality of the mesh, analysis of the cross-sections, and comparison of the volumes of heaps. As a result, the determination of heap volumes and documentation using digital aerial photogrammetry can be confirmed as an appropriate, efficient, fast, and accurate method. The difference in the detected volume was less than 0.1%, the mean difference of the meshes was less than 0.01 m, and the standard deviation was less than 0.05 m.
Effects of Connective Tissue Growth Factor on the Cell Viability, Proliferation, Osteogenic Capacity and mRNA Expression of Stem Cell Spheroids
Authors: Alnahash Abdullah Zaki , Song Young-Min , Min Sae-Kyung , Lee Hyun-Jin , Kim Min-Ji , Park Yoon-Hee , Park Je-Uk , Park Jun-Beom
Published: July 2021

Background: Connective tissue growth factor (CTGF) is a cellular communication network factor family protein involved in many cellular functions. The purpose of this study was to determine the effects of CTGF on the proliferation, osteogenic capacity, and mRNA expression of spheroids composed of gingiva-derived mesenchymal stem cells (GMSCs). Methods: CTGF was applied at final concentrations of 0, 25, 50, 100, and 200 ng/mL. Qualitative cell viability was determined using Live/Dead kit assay. Metabolic viability was determined with a colorimetric assay kit. Osteogenic activity was analyzed with alkaline phosphatase activity and Alizarin Red S staining. Quantitative polymerase chain reaction (qPCR) was used to assess the expression levels of RUNX2, BSP, OCN, and COL1A1. Results: In general, there was no significant difference in cell viability between the groups on Days 1, 4, and 7. Addition of CTGF produced an increase in Alizarin Red S staining. qPCR results demonstrated that the mRNA expression levels of RUNX2, BSP, OCN, and COL1A1 were significantly increased with the addition of CTGF. Conclusions: Based on these findings, we conclude that CTGF can be applied for increased osteogenic differentiation of stem cell spheroids.
Ion Beam Nanopatterning of Biomaterial Surfaces
Authors: Yang Yu , Keller Adrian
Published: July 2021

Ion beam irradiation of solid surfaces may result in the self-organized formation of well-defined topographic nanopatterns. Depending on the irradiation conditions and the material properties, isotropic or anisotropic patterns of differently shaped features may be obtained. Most intriguingly, the periodicities of these patterns can be adjusted in the range between less than twenty and several hundred nanometers, which covers the dimensions of many cellular and extracellular features. However, even though ion beam nanopatterning has been studied for several decades and is nowadays widely employed in the fabrication of functional surfaces, it has found its way into the biomaterials field only recently. This review provides a brief overview of the basics of ion beam nanopatterning, emphasizes aspects of particular relevance for biomaterials applications, and summarizes a number of recent studies that investigated the effects of such nanopatterned surfaces on the adsorption of biomolecules and the response of adhering cells. Finally, promising future directions and potential translational challenges are identified.
Vortex Ring Theory—An Alternative to the Existing Actuator Disk and Rotating Annular Stream Tube Theories
Authors: Agbormbai James , Zhu Weidong , Li Liang
Published: July 2021

Currently, the actuator disk theory (ADT) and the rotating annular stream-tube theory (RAST), both of which predicate on the axial momentum and generalized momentum theories, among others, are commonly used in investigating the aerodynamic characteristics of horizontal axis wind turbines (HAWTs). These theories, which are based on a rotor with an infinite number of blades, typically do not properly capture the flow physics of wind blowing past the rotors of HAWTs. A vortex ring theory (VRT) that analyzes HAWTs based solely on the characteristics of fluids flowing past obstructions is proposed. The VRT is not predicated on the assertion that the induced velocity in the wake is twice the induced velocity at the rotor. On the contrary, it splits the axial induction factor in the wake into two components, namely, the induction or interference factor due to the solidity of the rotor and the induction factor due to the wake of the rotor aw; aw and its azimuthal counterpart are determined using the Biot–Savart law. The pressure differences across the rotor segments of a HAWT are derived from the Bernoulli equation for all the three theories. Blade segment/local areas based on the blade sectional geometry of the rotor are used in the case of the VRT to estimate the local forces. All the calculations in this study are based on the design parameters of the 5 MW National Renewable Energy Laboratory’s reference offshore wind turbine. Pressure differences are plotted as functions of local radii using the calculated axial and azimuthal induction factors for each theory. The local power coefficient is plotted as a function of the local tip-speed ratio, while the local thrust coefficient is plotted as a function of the local radii for all the three theories. There is piece-wise agreement between the VRT, the ADT, the RAST and numerical and experimental data available in the literature.
Intelligent Control Systems in Urban Planning Conflicts: Social Media Users’ Perception
Authors: Gabdrakhmanova Nailia , Pilgun Maria
Published: July 2021

The relevance of this study is determined by the need to develop technologies for effective urban systems management and resolution of urban planning conflicts. The paper presents an algorithm for analyzing urban planning conflicts. The material for the study was data from social networks, microblogging, blogs, instant messaging, forums, reviews, video hosting services, thematic portals, online media, print media and TV related to the construction of the North-Eastern Chord (NEC) in Moscow (RF). To analyze the content of social media, a multimodal approach was used. The paper presents the results of research on the development of methods and approaches for constructing mathematical and neural network models for analyzing the social media users’ perceptions based on their digital footprints. Artificial neural networks, differential equations, and mathematical statistics were involved in building the models. Differential equations of dynamic systems were based on observations enabled by machine learning. Mathematical models were developed to quickly detect, prevent, and address conflicts in urban planning in order to manage urban systems efficiently. In combination with mathematical and neural network model the developed approaches, made it possible to draw a conclusion about the tense situation around the construction of the NEC, identify complaints of residents to constructors and city authorities, and propose recommendations to resolve and prevent conflicts. Research data could be of use in solving similar problems in sociology, ecology, and economics.
Pressure Drop Method as a Useful Tool for Detecting Rheological Properties of Non-Newtonian Fluids during Flow
Authors: Kaczmarczyk Kacper , Kruk Joanna , Ptaszek Paweł , Ptaszek Anna
Published: July 2021

The aim of the research was to develop a pressure drop measuring method dedicated to fluids under real flow through a pipeline. The measurement system is a set of appropriately configured flow meter and pressure sensors installed on the pipeline. The pressure drop values detected on the measuring section are sufficient to clearly determine the rheological properties of the fluid. The measuring system used for the tests consisted of a screw pump, two pressure sensors and an electromagnetic flow meter. The length of the measuring section was 4.12 m, and the internal diameter of the pipeline was 0.026 m. To calibrate of the measuring system a glycerol was used. As a model fluid, a 1% water solution of xanthan gum was used and was subjected to the flow at following shear rate conditions: 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65 s−1. The obtained raw experimental data included the pressure drop values and flow rate and they created full information about the fluid behavior during flow. According to the momentum balance equation, the rheological parameters of Ostwald de Waele model were estimated. The estimation procedure was carried out with the help of the Marquardt-Levenberg minimisation method. The same solutions simultaneously were tested with the help of a rotational rheometer. The data obtained from the pressure drop method were consistent with the results obtained from the rotational rheometer. The use of the pressure drop allows to determine the rheological properties of the non-newtonian fluids under the process conditions directly in the pipeline. In addition, it is possible to perform full rheological characteristics based on one flow rate under laminar conditions.
Spatial Variation of Water Chemistry in Aries River Catchment, Western Romania
Authors: Moldovan Ana , Hoaghia Maria-Alexandra , Török Anamaria Iulia , Roman Marius , Mirea Ionut Cornel , Barabas Reka , Micle Valer , Cadar Oana
Published: July 2021

This study aims to investigate the quality and vulnerability of surface water (Aries River catchment) in order to identify the impact of past mining activities. For this purpose, the pollution and water quality indices, Piper and Durov plots, as well vulnerability modeling maps were used. The obtained results indicate that the water samples were contaminated with As, Fe, Mn, Pb and have relatively high concentrations of SO42−, HCO3−, TDS, Ca, K, Mg and high values for the electrical conductivity. Possible sources of the high content of chemicals could be the natural processes or the inputs of the mine drainage. Generally, according to the pollution indices, which were correlated to high concentrations of heavy metals, especially with Pb, Fe and Mn, the water samples were characterized by heavy metals pollution. The water quality index classified the studied water samples into five different classes of quality, namely: unsuitable for drinking, poor, medium, good and excellent quality. Similarly, medium, high and very high vulnerability classes were observed. The Durov and Piper plots classified the waters into Mg-HCO3− and Ca-Cl− types. The past and present mining activities clearly change the water chemistry and alter the quality of the Aries River, with the water requiring specific treatments before use.
Effect of Grain Size and Micromorphology of Cu Foil on the Velocity of Flyer of Exploding Foil Detonator
Authors: Han Kehua , Deng Peng , Chu Enyi , Jiao Qingjie
Published: July 2021

In this paper, the effect of grain size and micromorphology of Cu foil on the velocity of the flyer of an exploding foil detonator was studied. A Cu foil with different grain sizes and micromorphologies was prepared by the physical vapor deposition sputtering method. The flyer velocity of the Cu foil was measured by the photon Doppler technique (PDT). The influence of the grain size and micromorphology of the Cu foil (which was the core transducer of the exploding foil detonator) on the flyer velocity and reacted morphology was discussed. The results show that the grain size and micromorphology of the Cu film can greatly affect the velocity and morphology of the flyer. The grain size of the Cu film is more uniform, and the stimulus response in the middle area of the bridge foil is more concentrated. In addition, the current density becomes more uniform, resulting in a better explosion performance. Consequently, the speed of the formed flyer becomes higher, leading to a smoother flyer surface, which is more conductive to energy conversion.
A Comparison of Cone Beam Computed Tomography and Periapical Digital Radiography for Evaluation of Root Canal Preparation
Authors: Pham Khoa Van
Published: July 2021

The aim of the present study is to compare cone beam computed tomography and periapical digital radiography for the evaluation of root canal preparation. Nine extracted human molars were used in this study. Following access cavity preparation, mesio-buccal roots of maxillary and mesial roots of mandibular molars were prepared and the remaining roots were cut off. Three amalgam cavities were prepared on the coronal part of the teeth and were filled with amalgam to be used as landmarks. Specimens were scanned using cone-beam computed tomography and periapical digital radiograph images were obtained before and after root canal preparation. WaveOne Gold Primary was used for root canal preparation to full working length. Specimens were then scanned using CBCT and a periapical radiograph for the after-instrumentation images. The transportation and centering ratio were measured and calculated on the CBCT and periapical radiographic images. The Bland–Altman method was used for detecting the bias in the evaluation of agreement between the two methods’ measurements. There was agreement between the two methods’ measurements using CBCT scans and periapical digital radiographic images in the evaluation of transportation and centering ratio parameters. The two methods could be used interchangeably in measurements of transportation and calculating the centering ratio.
Multistate Diagnosis and Prognosis of Lubricating Oil Degradation Using Sticky Hierarchical Dirichlet Process–Hidden Markov Model Framework
Authors: Tanwar Monika , Park Hyunseok , Raghavan Nagarajan
Published: July 2021

In this study, we present a state-based diagnostic and prognostic methodology for lubricating oil degradation based on a nonparametric Bayesian approach, i.e., sticky hierarchical Dirichlet process–hidden Markov model (HDP-HMM). An accurate health state-space assessment for diagnostics and prognostics has always been unobservable and hypothetical in the past. The lubrication condition monitoring (LCM) data is generally segregated as “healthy or unhealthy”, representing a binary state-based perspective to the problem. This two-state performance-based formulation poses limitations to the precision and accuracy of the diagnosis and prognosis for real data wherein there may be multiple states of discrete performance that are characteristic of the system functionality. In particular, the reversible and nonlinear time-series trends of degradation data increase the complexity of state-based modeling. We propose a multistate diagnostic and prognostic framework for LCM data in the wear-out phase (i.e., the unhealthy portion of degradation data), accounting for irregular oil replenishment and oil change effects (i.e., nonlinearity in the degradation signal). The LCM data is simulated for an elementary mechanical system with four components. The sticky HDP sets the prior for the HMM parameters. The unsupervised learning over infinite observations and emission reveals four discrete health states and helps estimate the associated state transition probabilities. The inferred state sequence provides information relating to the state dynamics, which provides further guidance to maintenance decision making. The decision making is further backed by prognostics based on the conditional reliability function and mean residual life estimation.
Impact of Post-Earthquake Seismic Waves on the Terrestrial Environment
Authors: Zeng Xiangzhi , Yang Wencai
Published: July 2021

When an earthquake occurs, it is not only the crustal material in the seismic zone that moves violently; the seismic waves of the earthquake with certain level of energy can act on the crust over large areas, producing remote effects that affect the living environment. According to the records of the long-term observation station of Chinese Continental Scientific Drilling, the effects of near-surface crust caused by the post-earthquake seismic waves include the following four aspects: (1) the pore fissure loosening; (2) the pore pressure rising and groundwater upwelling; (3) gas releasing; and (4) exothermic reaction. The effects of groundwater upwelling, gas releasing and exothermic reaction may be superimposed on the process of global warming, which has a certain impact on the terrestrial environment and requires further studies.
Complex Processing of Saponite Waste from a Diamond-Mining Enterprise
Authors: Zubkova Olga , Alexeev Aleksey , Polyanskiy Arseniy , Karapetyan Kirill , Kononchuk Olga , Reinmöller Markus
Published: July 2021

The solution of the sludge utilization problem and yield increase at processing plants have great importance today all over the world. Disasters associated with the tailings dams failures have madeus develop technologies of tailings sludge utilization as a commercial product, reducing the environmental damage on the regions of mineral extraction. This research aimed to provide new data, methods and an analytical approach to solve the saponite sludge accumulation problem on mining enterprises with silicate coagulant to increase the rate of cycle water clarification for the enrichment process and the recycling of sludge to reduce its hazardous effect. Samples were taken in the deposit located in the north of the European part of Russia, where diamond bearing ore contain montmorillonite minerals, mostly saponite, which is considered to be a perspective secondary product. The content of this mineral in the sludge is above 20 wt.%. Saponite is a clay mineral with the general chemical formula (Ca,Na)0.3(Mg, Fe2+)3(Si, Al)4O10(OH)2·4H2O. The mineral has high adsorption, ion exchange, and catalytic and filtration properties; due to the developed diffuse layer, saponite particles are highly stable in an aqueous medium—the resulting suspension is highly stable and has slow sedimentation. During the research, a positive effect on the sedimentation process of clay saponite particles was established, due to the introduction of a coagulant containing 70% tricalcium silicate, at a dosage of 2 g/dm3 coagulant; the degree of purification of water containing the saponite clay suspension is 99%. The condensed sediment after the thermal drying and with the limestone addition can be used again as a coagulant or secondary product with enhanced properties;therefore, the sludge will be processed, and not stored.
Development of a New Pasta Product by the Incorporation of Chestnut Flour and Bee Pollen
Authors: Brochard Maëlys , Correia Paula , Barroca Maria João , Guiné Raquel P. F.
Published: July 2021

This work aimed at developing fortified pastas incorporating chestnut flour (25–55%) and powdered pollen (5–20%), either separately or in combination, as well as the characterization of the products obtained. To this, a physical characterization was carried out (analyzing texture and color), complemented with chemical analyses to determine the nutritional composition. Results showed that adding chestnut flour over 40% to wheat-flour pasta shortened optimum cooking time and lowered cooking yield, and the addition to pasta prepared with wheat flour and eggs maintained approximately constant the cooking yield. Additionally, the incorporation of pollen powder (up to 20%) in pasta prepared with wheat flour and water or fresh egg shortened the cooking time and cooking yield, in both fresh and dried pasta. The most suitable percentages of the new ingredients were 50% for chestnut and 10% for pollen. Comparing with the control pasta recipe (wheat flour and egg), the addition of chestnut flour (50%) or pollen powder (10%) increased stickiness, adhesiveness and the darkening of the final product (fresh or dried) but maintained the firmness of the pasta. The cooking of fresh or dried pasta enriched with both ingredients turned the pasta clearer and slightly stickier. On the other hand, the addition of chestnut flour and pollen powder in pasta formulation delivered a nutritionally balanced product with high fiber, vitamins and minerals. Overall, chestnut flour and powdered pollen represent promising ingredients for the development of functional fresh and dried pasta formulations.
Stable Convergence Theorems for Products of Uniformly Continuous Mappings in Metric Spaces
Authors: Zaslavski Alexander J.
Published: July 2021

We study the behavior of inexact products of uniformly continuous self-mappings of a complete metric space that is uniformly continuous and bounded on bounded sets. It is shown that previously established convergence theorems for products of non-expansive mappings continue to hold even under the presence of computational errors.
Identification of Degradation Mechanisms by Post-Mortem Analysis for High Power and High Energy Commercial Li-Ion Cells after Electric Vehicle Aging
Authors: Kuntz Pierre , Raccurt Olivier , Azaïs Philippe , Richter Karsten , Waldmann Thomas , Wohlfahrt-Mehrens Margret , Bardet Michel , Buzlukov Anton , Genies Sylvie
Published: July 2021

Driven by the rise of the electric automotive industry, the Li-ion battery market is in strong expansion. This technology does not only fulfill the requirements of electric mobility, but is also found in most portable electric devices. Even though Li-ion batteries are known for their numerous advantages, they undergo serious performance degradation during their aging, and more particularly when used in specific conditions such as at low temperature or high charging current rates. Depending on the operational conditions, different aging mechanisms are favored and can induce physical and chemical modifications of the internal components, leading to performance decay. In this article, the identification of the degradation mechanisms was carried out thanks to an in-depth ante- and post mortem study on three high power and high energy commercial 18,650 cells. Li-ion cells were aged using a battery electric vehicle (BEV) aging profile at −20 °C, 0 °C, 25 °C, and 45 °C in accordance with the international standard IEC 62-660, and in calendar aging mode at 45 °C and SOC 100%. Internal components recovered from fresh and aged cells were investigated through different electrochemical (half-coin cell), chemical (EDX, GD-OES, NMR), and topological (SEM) characterization techniques. The influence of power and energy cells’ internal design and Si content in the negative electrode on cell aging has been highlighted vis-à-vis the capacity and power fade.