bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the Influence of Nonlinear Moments upon Intensity of Parametric Roll
Authors: Semenova Victoria , Rozhdestvensky Kirill , Albaev Danil , Htet Zin Min
Published: August 2022

Hydrodynamical analysis of the conditions for the occurrence of chaotic ship roll, leading in some cases to the capsizing of the vessel, showed that such conditions are most likely to occur in the zone of the main parametric resonance of the roll when its period is sequentially doubled, and subharmonic oscillations turn into chaotic ones. This circumstance necessitates special attention to the regime of parametric roll resonance, issues of its occurrence, development, and establishment as well as to the methods of calculation of its amplitudes. In the present paper, the study of the parametric ship roll is conducted on the basis of the Lugovsky formula. An account is taken of the additional nonlinear moments M¯X23 and M¯X24, obtained through the application of the small parameter method. Presented are the calculation results for the parametric roll of five different ships performing motions at various course angles both with and without account of the aforementioned nonlinear moments. Demonstrated therewith is a significant influence of the nonlinear moments upon the maximum amplitudes of the parametric roll, especially in the case of beam waves.
Application of the Trigonometric Polynomial Interpolation for the Estimation of the Vertical Eddy Viscosity Coefficient Based on the Ekman Adjoint Assimilation Model
Authors: Wu Xinping , Xu Minjie , Gao Guandong , Yin Baoshu , Lv Xianqing
Published: August 2022

In this study, a triangular polynomial interpolation (TPI) scheme was developed to estimate the vertical eddy viscosity coefficient (VEVC) on the basis of the Ekman model with adjoint assimilation. In the twin experiments, the advantages and disadvantages of estimating the VEVC using the TPI scheme under different factors are discussed. The results indicated that (1) the TPI scheme proves to be better than the cubic spline interpolation (CSI) and Cressman interpolation (CI) schemes; (2) the inversion results are more sensitive to observations from upper ocean layers than those from lower layers, and the TPI scheme is less likely to be influenced by missing data; (3) for various boundary layer depths, the inversion results of the TPI scheme remain consistent with the given distributions; (4) the inversion results can be influenced considerably by observational errors, and the TPI scheme is more resistant to noise than the CSI and CI schemes; and (5) the inversion accuracy of the TPI scheme can be improved by selecting the temporal wind stress drag coefficients. In practical experiments, the adjoint method with the TPI scheme was developed to estimate the Ekman currents by assimilating the observations from a buoy stationed in the Yellow Sea. The results showed the successful estimation of the VEVC and demonstrated that more precise current velocities can be obtained with this estimation scheme. In summary, this study provides a useful approach for the effective estimation of the VEVC.
Time–Frequency Characteristics of Global SST Anomalies in the Past 100 Years: A Metrological Approach
Authors: Tang Chaoli , Hao Dewei , Wei Yuanyuan , Zhu Fangzheng , Wu Xin , Tian Xiaomin
Published: August 2022

To comprehensively explore the characteristics of global SST anomalies, a novel time–frequency combination method, based on the COBE data and NCEP/NCAR reanalysis products in the past 100 years, was developed. From the view of the time domain, the global SST generally showed an upward trend from 1920 to 2019, the upward trend was significant after 1988, and the growth mutation occurred in 1930, according to the Mann–Kendall (MK) mutation test. Moreover, we extracted spatiotemporal modes of SST anomalies’ variability by empirical orthogonal function (EOF) analysis and obtained global spatial EOFs that closely correspond to regionally defined climate modes. Our results demonstrated that El Niño–Southern Oscillation (ENSO) is the typical character for the first mode of SST anomaly EOF, and Atlantic multidecadal oscillation (AMO) for the second. From the view of the frequency domain, our data suggested that there is a multi-period nesting phenomenon in global SST variations, in which the first main cycle with the most obvious oscillation was a 30-year cycle and changed in 20-year cycles, and the second cycle was a 15-year cycle and changed in 10-year cycles through wavelet analysis. As for the perspective of time–frequency characteristics, the dominant period of ENSO in the first mode of EOF is 4 years, obtained through filtering and cross wavelet transform. In addition, SST anomalies will maintain an upward trend for the next 60 months, according to the seasonal autoregressive integrated moving average (SARIMA) model, which has the potential value for predicting ENSO.
De Novo Long-Read Whole-Genome Assemblies and the Comparative Pan-Genome Analysis of Ascochyta Blight Pathogens Affecting Field Pea
Authors: Ogaji Yvonne O. , Lee Robert C. , Sawbridge Tim I. , Cocks Benjamin G. , Daetwyler Hans D. , Kaur Sukhjiwan
Published: August 2022

Ascochyta Blight (AB) is a major disease of many cool-season legumes globally. In field pea, three fungal pathogens have been identified to be responsible for this disease in Australia, namely Peyronellaea pinodes, Peyronellaea pinodella and Phoma koolunga. Limited genomic resources for these pathogens have been generated, which has hampered the implementation of effective management strategies and breeding for resistant cultivars. Using Oxford Nanopore long-read sequencing, we report the first high-quality, fully annotated, near-chromosome-level nuclear and mitochondrial genome assemblies for 18 isolates from the Australian AB complex. Comparative genome analysis was performed to elucidate the differences and similarities between species and isolates using phylogenetic relationships and functional diversity. Our data indicated that P. pinodella and P. koolunga are heterothallic, while P. pinodes is homothallic. More homology and orthologous gene clusters are shared between P. pinodes and P. pinodella compared to P. koolunga. The analysis of the repetitive DNA content showed differences in the transposable repeat composition in the genomes and their expression in the transcriptomes. Significant repeat expansion in P. koolunga’s genome was seen, with strong repeat-induced point mutation (RIP) activity being evident. Phylogenetic analysis revealed that genetic diversity can be exploited for species marker development. This study provided the much-needed genetic resources and characterization of the AB species to further drive research in key areas such as disease epidemiology and host–pathogen interactions.
Pseudo-Chromosomal Genome Assembly in Combination with Comprehensive Transcriptome Analysis in Agaricus bisporus Strain KMCC00540 Reveals Mechanical Stimulus Responsive Genes Associated with Browning Effect
Authors: Jo Ick-Hyun , Kim Jaewook , An Hyejin , Lee Hwa-Yong , So Yoon-Sup , Ryu Hojin , Sung Gi-Ho , Shim Donghwan , Chung Jong-Wook
Published: August 2022

Agaricus bisporus is one of the world’s most popular edible mushrooms, including in South Korea. We performed de novo genome assembly with a South Korean white-colored cultivar of A. bisporus, KMCC00540. After generating a scaffold-level genomic sequence, we inferred chromosome-level assembly by genomic synteny analysis with the representative A. bisporus strains H97 and H39. The KMCC00540 genome had 13 pseudochromosomes comprising 33,030,236 bp mostly covering both strains. A comparative genomic analysis with cultivar H97 indicated that most genomic regions and annotated proteins were shared (over 90%), ensuring that our cultivar could be used as a representative genome. However, A. bisporus suffers from browning even from only a slight mechanical stimulus during transportation, which significantly lowers its commercial value. To identify which genes respond to a mechanical stimulus that induces browning, we performed a time-course transcriptome analysis based on the de novo assembled genome. Mechanical stimulus induces up-regulation in long fatty acid ligase activity-related genes, as well as melanin biosynthesis genes, especially at early time points. In summary, we assembled the chromosome-level genomic information on a Korean strain of A. bisporus and identified which genes respond to a mechanical stimulus, which provided key hints for improving the post-harvest biological control of A. bisporus.
Genome-Wide Identification and Characterization of Toll-like Receptors (TLRs) in Diaphorina citri and Their Expression Patterns Induced by the Endophyte Beauveria bassiana
Authors: Ramos Aguila Luis Carlos , Ashraf Hafiza Javaira , Sánchez Moreano Jessica Paola , Akutse Komivi Senyo , Bamisile Bamisope Steve , Lu Liuyang , Li Xiaofang , Lin Jingyi , Wu Qing , Wang Liande
Published: August 2022

Toll-like receptors (TLRs) are pathogen recognition receptors (PRRs), which play key roles in helping the host immune system fight pathogen invasions. Systematic information on TLRs at the genome-wide level and expression profiling in response to endophytic colonization is very important to understand their functions but is currently lacking in this field. Here, a total of two TLR genes were identified and characterized in Diaphorina citri. The TLR genes of D. citri were clustered into five families according to the phylogenetic analysis of different species’ TLRs. The domain organization analyses suggested that the TLRs were constituted of three important parts: a leucine-rich repeat (LRR) domain, a transmembrane region (TR) and a Toll/interleukin-1 receptor (TIR) domain. The mRNA expression levels of the two TLR genes (DcTOLL and DcTLR7) were highly regulated in both nymphs and adults of D. citri. These results elucidated the potentiated TLR gene expression in response to endophytically colonized plants. Furthermore, the 3D structures of the TIR domain were highly conserved during evolution. Collectively, these findings elucidate the crucial roles of TLRs in the immune response of D. citri to entomopathogens systematically established as endophytes, and provide fundamental knowledge for further understanding of the innate immunity of D. citri.
Feral Animal Populations: Separating Threats from Opportunities
Authors: Rodríguez-Rodríguez Eduardo J. , Gil-Morión Jesús , Negro Juan J.
Published: August 2022

Feral animals are those that live in the wild but are descendants of domesticated populations. Although, in many cases, these feral populations imply a demonstrable risk to the ecosystems in which they live and may conflict with local wild species and human activities, there are feral populations that are considered worth preserving and, in some cases, they already enjoy protection by interest groups and even public authorities. In this review, we aim to identify valuable populations using three criteria: (a) Genetic conservation value (for instance, if the wild ancestor is extinct), (b) the niche occupancy criterion and, finally, (c) a cultural criterion. We propose a detailed analysis of feral populations under scrutiny, supporting control measures when necessary, but also allowing for international protection at the same level as wild animals for feral taxa of special concern. Feral taxa, which are already in the focus of conservation efforts, and should be awarded extended recognition and protection, mainly include ancient lineages with relevant genetic or cultural importance.
Urbanization Influences CO2 Emissions in the Pearl River Delta: A Perspective of the “Space of Flows”
Authors: Zhao Yabo , Chen Ruiyang , Sun Tong , Yang Ying , Ma Shifa , Xie Dixiang , Zhang Xiwen , Cai Yunnan
Published: August 2022

As the largest carbon emitter in the world, China is facing increasing challenge to reduce CO2 emissions. Given this issue, exploring the influencing factors is of great significance for scientific low-carbon emission policymaking. Although previous literature has explored the effects of urbanization on CO2 emissions, the impact of the space of flow on urban carbon emissions have been less explored. Due to the increasing connection between cities, its impact on urban carbon emissions cannot be ignored. Thus, this paper takes the space of flows into account as an aspect of urbanization to supplement the existing literature and empirically examines the multiple effects of urbanization on CO2 emissions in the Pearl River Delta (PRD) urban agglomeration. By using a STIRPAT model, statistical data, and web crawler data, we examined impacts of different types of urbanization on CO2 emissions. Our empirical results show that: (1) Within the PRD urban agglomeration, urban linkage intensity is strongly connected to urban socioeconomic growth, establishing a geographical structure with Guangzhou and Shenzhen as the double core. (2) Our results show that urbanization exerts two opposite effects on CO2 emissions: positively connects carbon emissions with population urbanization, integrated urban linkage flow, and energy intensity, whereas economic urbanization and social urbanization are shown to be negatively correlated. However, spatial urbanization has no significant positive effect on urban CO2 emissions. (3) It is worth noting that urban linkage flows are the second most important factor affecting urban carbon emissions after economic urbanization. Our study could formulate effective planning suggestions for future CO2 emission reduction paths and development modes in the PRD.
Research Progress Regarding the Use of Metal and Metal Oxide Nanoparticles as Lubricant Additives
Authors: Du Fengming , Li Cong , Li Dawei , Sa Xiaoxia , Yu Yang , Li Chengdi , Yang Yuxing , Wang Jinlong
Published: August 2022

Lubricating oil can effectively reduce friction between mechanical parts, thereby reducing energy consumption and improving service life and reliability. Due to the development of science and technology, it is necessary to improve the performance of lubricating oil to fulfill the higher tribological requirements for countering wear and providing lubrication. Nanolubricant additives have the four lubrication mechanisms of micro-bearing, protective film, polishing, and repair effects. A nanolubricant additive can often demonstrate a variety of lubrication mechanisms at the same time. As lubricating additives, metal and metal oxide nanoparticles have outstanding effects which improve the tribological properties of lubricating oil and have been widely studied in the field of tribology. This paper introduces the lubrication mechanism of nanoadditives and the latest research results for metal and metal-oxide nanoparticle lubrication additives.
Nano- and Micro-Tribological Investigations of Boundary Layers on Axial Bearing Washers Tested under WEC Critical Conditions
Authors: Pape Florian
Published: August 2022

The formation of boundary layers on bearing surfaces due to the operational conditions has a significant influence on bearing lifetimes and frictional properties. Zinc dialkyldithiophosphate is an anti-wear additive widely used in oil and grease formulations that forms beneficial surface boundary layers. Under certain circumstances, this additive can cause early bearing failure due to white etching cracks (WEC) formation. By influencing chemical reactions and diffusion processes, the boundary films are suspected to be a reason for the emergence of WECs. The properties of these layers under WEC critical and uncritical conditions are of interest. To gain knowledge of these layers, nano- and micro-tribological tests were performed. One possibility is to measure the hardness by nanoindentation and scratching on and into the layers by nano scratch tests. Another way is to perform local resolved micro-pin-on-disk tests. Additionally, ToF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) was performed on the bearing surfaces to conclude the chemical compositions of the boundary layers. In the focus was, if the measured properties of the layers can be correlated to the bearing’s early failures due to WEC, frictional properties of the whole system, and the wear on the surfaces.
3-Methoxy-5-methyl-12-phenylbenzacridinium Iodide
Authors: Uktamova Malokhat , Koga Rintaro , Mukhamedjonova Fotima , Kholikov Tursunali , Ibragimov Bakhtiyor , Torikai Kohei , Khodjaniyazov Khamid
Published: August 2022

N-alkylacridinium derivatives are some of the most popular azo dye templates. Herein, we report the synthesis of 3-methoxy-5-methyl-12-phenylbenzacridinium iodide (MMPBAI) via N-alkylation. The structure of MMPBAI was elucidated using 1H Nuclear magnetic resonance (NMR), 13C NMR, Electronspray ionization mass spectrometry (ESI-MS), and Fourier-transform infrared spectroscopy (FT-IR). MMPBAI could not visualize double-stranded DNA in agarose gel, although the structural core would still be interesting as a template for new azo dyes.
CVD Nanocrystalline Diamond Film Doped with Eu
Authors: Yudina Elena B. , Aleksenskii Alexander E. , Bogdanov Sergey A. , Bukalov Sergey S. , Leites Larisa A. , Radishev Dmitry B. , Vikharev Anatoly L. , Vul’ Alexander Y.
Published: August 2022

This paper submits experimental results of a study directed towards the formation of Eu ions’ luminescent centers in CVD diamond films. A new approach is based on use of diamond nanoparticles with a surface modified with Eu ions for seeding at CVD growth. Nanocrystalline diamond films (NCD) doped with Eu have been grown from the gas phase on silicon substrates by microwave plasma-assisted CVD at a frequency of 2.45 GHz. The photoluminescence spectra clearly show several electronic transitions of the Eu3+ ions, which confirm the incorporation of Eu ions into the NCD film.
The Effect of Pr Doping Contents on the Structural, Microstructure and Dielectric Properties of BaBi2Nb2O9 Aurivillius Ceramics
Authors: Rerak Michał , Makowska Jolanta , Osińska Katarzyna , Goryczka Tomasz , Zawada Anna , Adamczyk-Habrajska Małgorzata
Published: August 2022

Aurivillius BaBi2Nb2O9 and Ba1-xPrxBi2Nb2O9 ceramics were successfully synthesized by a simple solid state reaction method. Ceramics were prepared from reactants: Nb2O5, Bi2O3, BaCO3 and Pr2O3. The microstructure, structure, chemical composition, and dielectric properties of the obtained materials were examined. Dielectric properties were investigated in a wide range of temperatures (T = 20–500 °C) and frequencies (f = 0.1 kHz–1 MHz). The obtained ceramic materials belong to the group of layered perovskites, crystallizing in a tetragonal structure with the space group I4/mmm. Modification of the barium niobate compound with praseodymium ions influenced its dielectric properties and introducing a small concentration of the dopant ion causes a slight increase in the value of electric permittivity and shifts its maximum towards higher temperatures.
Experimental Study on Seismic Performance of Precast Pretensioned Prestressed Concrete Beam-Column Interior Joints Using UHPC for Connection
Authors: Xiong Xueyu , Xie Yifan , Yao Gangfeng , Liu Ju , Yan Laizhang , He Liang
Published: August 2022

The traditional connections and reinforcement details of precast RC frames are complex and cause difficulty in construction. Ultra-high-performance concrete (UHPC) exhibits outstanding compressive strength and bond strength with rebars and strands; thus, the usage of UHPC in the joint core area will reduce the amount of transverse reinforcement and shorten the anchoring length of beam rebars as well as strands significantly. Moreover, the lap splice connections of precast columns can be placed in the UHPC joint zone and the construction process will be simplified. This paper presented a novel joint consisting of a precast pretensioned prestressed concrete beam, an ordinary precast reinforced concrete (RC) column, and a UHPC joint zone. To study the seismic performance of the proposed joints, six novel interior joints and one monolithic RC joint were tested under low-cyclic loads. Variables such as the axial force, the compressive strength of UHPC, the stirrup ratio were considered in the tests. The test results indicate that the proposed joints exhibit comparable seismic performance of the monolithic RC joint. An anchorage length of 40 times the strands-diameter and a lap splice length of 16 times the rebar-diameter are adequate for prestressed strands and precast column rebars, respectively. A minimum column depth is suggested as 13 times the diameter of the beam-top continuous rebars passing through the joint. In addition, a nine-time rebar diameter is sufficient for the anchorage of beam bottom rebars. The shear strength of UHPC in the joint core area is suggested as 0.8 times the square root of the UHPC compressive strength.
Durability of Recycled Concrete Aggregates Prepared with Mechanochemical and Thermal Treatment
Authors: Yunusa Mujaheed , Zhang Xiaoshan , Cui Peiqiang , Tian Xiaowu
Published: August 2022

Recycled concrete aggregates (RCAs) have low quality when compared with natural or conventional aggregates as the paste adhering to it is the key aspect that affects its functionality. Since the adhering cementitious paste weakens the adhesion between the aggregate and the binder, it becomes a decisive factor in the mechanical behavior of the asphalt mixture. It turns out that enhancing the surface of the aggregate or eliminating the paste attached to the NA (natural aggregate) is crucial for improving interfacial bonding. Therefore, the treatment and evaluation of the RCAs by laboratory testing method were studied in this research to assess their reuse in the asphalt pavement surface coarse layer. With the various techniques for removing paste from the RCA, a combination of three enhancement processes were developed for the effective removal of the cement paste, which are mechanical, chemical, and 400 °C conditioning thermal treatment. The RCAs were first charged in a Los Angeles machine for the mechanical treatment to remove parts of the attached cement. Then they were soaked in two types of acids, namely hydrochloric and sulfuric, with different concentrations to determine the most effective or optimum molarity for about a 48 h soaking duration. Then a 2 h thermal treatment was conducted on the RCA samples. After all the treatments were done, the RCA aggregates were subjected to different types of tests to examine their properties in order to ensure their full potential in terms of their physical, chemical, mineralogical, and surface microstructure characteristics. Based on the experiment design, the study intends to examine the quality of the treated recycled aggregates generated by the combination approach as well as to investigate the optimal acid concentration and type. The results show that the proposed mechanochemical and thermal treatment reinforced the quality of the RCAs when compared to the non-treated samples. Meanwhile, HCl proved to be the optimum compared to H2SO4 in most examinations of the properties. In the end, better chemical qualities were validated, and the RCA qualities were improved.
A Method for Measurement of Workpiece form Deviations Based on Machine Vision
Authors: Zhang Wei , Han Zongwang , Li Yang , Zheng Hongyu , Cheng Xiang
Published: August 2022

Machine vision has been studied for measurements of workpiece form deviations due to its ease of automation. However, the measurement accuracy limits its wide implementation in industrial applications. In this study, a method based on machine vision for measurement of straightness, roundness, and cylindricity of a workpiece is presented. A subsumed line search algorithm and an improved particle swarm optimization algorithm are proposed to evaluate the straightness and roundness deviations of the workpiece. Moreover, an image evaluation method of cylindricity deviation by the least-square fitting of the circle’s center coordinates is investigated. An image acquisition system incorporating image correction and sub-pixel edge positioning technology is developed. The performance of the developed system is evaluated against the measurement results of the standard cylindricity measuring instrument. The differences in the measurement of straightness, roundness, and cylindricity are −4.69 μm, 3.87 μm, and 8.51 μm, respectively. The proposed method would provide a viable industrial solution for the measurement of workpiece form deviations.
Loco-Manipulation Control for Arm-Mounted Quadruped Robots: Dynamic and Kinematic Strategies
Authors: Xin Guiyang , Zeng Fanlian , Qin Kairong
Published: August 2022

The studies on quadruped robots equipped with arms are still rare at the moment. The interaction between the arm and the quadrupedal platform needs to be handled by whole-body controllers. This paper presents an optimization-based dynamic whole-body controller to solve the problem of when the robot stands still for manipulation. In order to reduce the strong interaction when the robot is trotting, we keep using the whole-body controller to handle locomotion control and resort to joint PD controllers for the arm’s manipulation coupled with the mobile base on the kinematic level. Simulation results validate the expected locomotion and manipulation functionalities in both manipulation mode and loco-manipulation mode. The proposed control strategies are able to use the redundancy to perform multiple tasks in a dynamic system as such with 24 degrees of freedom.
Review of Methods, Applications and Publications on the Approximation of Piecewise Linear and Generalized Functions
Authors: Aliukov Sergei , Alabugin Anatoliy , Osintsev Konstantin
Published: August 2022

Approximation of piecewise linear and generalized functions is an important and difficult problem. These functions are widely used in mathematical modeling of various processes and systems, such as: automatic control theory, electrical engineering, radio engineering, information theory and transmission of signals and images, equations of mathematical physics, oscillation theory, differential equations and many others. The widespread use of such functions is explained by their positive properties. For example, piecewise linear functions are characterized by a simple structure over segments. However, these features also have disadvantages. For example, in the case of using piecewise linear functions, solutions have to be built in segments. In this case, the problem of matching the obtained solutions at the boundaries of the segments arises, which leads to the complication of the research results. The use of generic functions has similar disadvantages. To eliminate shortcomings in practice, one resorts to the approximation of these functions. There are a large number of well-known methods for approximating piecewise linear and generalized functions. Recently, new methods for their approximation have been developed. In this study, an attempt was made to generalize and discuss the existing methods for approximating the considered functions. Particular emphasis is placed on the description of new approximation methods and their applications in various fields of science and technology. The publication-based review discusses the strengths and weaknesses of each method, compares them, and considers suitable application examples. The review will undoubtedly be interesting not only for mathematicians, but also for specialists and scientists working in various applied fields of research.
A Refined Closed-Form Solution for Laterally Loaded Circular Membranes in Frictionless Contact with Rigid Flat Plates: Simultaneous Improvement of Out-of-Plane Equilibrium Equation and Geometric Equation
Authors: Li Fei-Yan , Li Xue , Zhang Qi , He Xiao-Ting , Sun Jun-Yi
Published: August 2022

Essential to the design and development of circular contact mode capacitive pressure sensors is the ability to accurately predict the contact radius, maximum stress, and shape of a laterally loaded circular membrane in frictionless contact with a concentric circular rigid flat plate. In this paper, this plate/membrane contact problem is solved analytically again by simultaneously improving both out-of-plane equilibrium equation and geometric equation, and a new and more refined closed-form solution is given to meet the need of accurate prediction. The new closed-form solution is numerically discussed in convergence and effectiveness and compared with the previous one, showing that it can greatly improve the prediction accuracy of the contact radius, maximum stress, and shape of the circular membrane in frictionless contact with the rigid flat plate.
Tail Index Estimation of PageRanks in Evolving Random Graphs
Authors: Markovich Natalia , Ryzhov Maksim , Vaičiulis Marijus
Published: August 2022

Random graphs are subject to the heterogeneities of the distributions of node indices and their dependence structures. Superstar nodes to which a large proportion of nodes attach in the evolving graphs are considered. In the present paper, a statistical analysis of the extremal part of random graphs is considered. We used the extreme value theory regarding sums and maxima of non-stationary random length sequences to evaluate the tail index of the PageRanks and max-linear models of superstar nodes in the evolving graphs where existing nodes or edges can be deleted or not. The evolution is provided by a linear preferential attachment. Our approach is based on the analysis of maxima and sums of the node PageRanks over communities (block maxima and block sums), which can be independent or weakly dependent random variables. By an empirical study, it was found that tail indices of the block maxima and block sums are close to the minimum tail index of representative series extracted from the communities. The tail indices are estimated by data of simulated graphs.
Unbiased Identification of Fractional Order System with Unknown Time-Delay Using Bias Compensation Method
Authors: Yakoub  Zaineb , Naifar Omar , Ivanov Dmitriy
Published: August 2022

In the field of engineering, time-delay is a typical occurrence. In reality, the inner dynamics of many industrial processes are impacted by delay or after-effect events. This paper discusses the identification of continuous-time fractional order system with unknown time-delay using the bias compensated least squares algorithm. The basic concept is to remove the imposed bias by including a correction term into the least squares estimations. The suggested approach makes a significant contribution by the estimation, iteratively, of fractional order system coefficients as well as the orders and the time-delay using a nonlinear optimization algorithm. The main advantage of this method is to provide a simple and powerful algorithm with good accuracy. The suggest method performances are assessed through two numerical examples.
How Do Financial Development and Renewable Energy Affect Consumption-Based Carbon Emissions?
Authors: Awosusi Abraham Ayobamiji , Adebayo Tomiwa Sunday , Rjoub Husam , Wong Wing-Keung
Published: August 2022

This paper bridges the gap in the literature by employing the novel quantile-on-quantile (QQ) approach, the quantile regression approach, and the nonparametric Granger causality test in quantiles to assess the effect of international trade on consumption-based carbon emissions (CCO2e) in Uruguay. Our study incorporates other drivers of CCO2 emissions, such as financial development and renewable energy, into the model. We find that, in the majority of the quantiles, exports, financial development, and renewable energy exert a negative impact on CCO2e, and the influence of imports on CCO2e is positive in all quantiles. Moreover, the quantile regression approach is used as a robustness test for the quantile-on-quantile approach. The causal interaction from the regressors to CCO2e is evaluated using the nonparametric Granger causality test in quantiles. The outcome of the nonparametric Granger causality test in quantiles suggests that imports, exports, renewable energy, and financial development can predict CCO2e at different quantiles. Based on these outcomes, we recommend that the financial sector must strengthen its focus on giving funding to enterprises that embrace environmentally friendly technologies and incentivize them to employ other energy-efficient technologies for manufacturing reasons, thereby preventing environmental deterioration.
An Insight into the Role of Marine Biopolymer Alginate in Endodontics: A Review
Authors: Lin Galvin Sim Siang , Cher Chia Yee , Goh Yong Hong , Chan Daryl Zhun Kit , Karobari Mohmed Isaqali , Lai Josephine Chang Hui , Noorani Tahir Yusuf
Published: August 2022

Alginate is a natural marine biopolymer that has been widely used in biomedical applications, but research on its use as an endodontic material is still sparse in the literature. This pioneer review aims to summarize the emerging roles of alginate and to outline its prospective applications as a core biomaterial in endodontics. Ten electronic databases and five textbooks were used to perform a search of English-language literature on the use of alginate in endodontics published between January 1980 and June 2022. The risk of bias (RoB) of each included study was assessed using the Office of Health Assessment and Translation (OHAT) tool. Subsequently, studies were categorized into three tiers to represent the overall risk. Qualitative analysis was performed, and the articles were sorted into different thematic categories. An initial search yielded a total of 1491 articles, but only 13 articles were chosen. For most domains, all the studies were rated with ‘probably low’ or ‘definitely low’ RoB, except for domains 2 and 6. All included studies fall in the Tier 1 category and were either in vitro, in vivo, or ex vivo. Four thematic categories were identified: endodontic regeneration, intracanal medicament, filing material, and chelating agent. Based on the available evidence, alginate has emerged as a cell carrier and scaffold in regenerative endodontics, a microcapsule delivery system for intracanal medicaments, a chelating agent reinforcing material, and a root canal sealer. More well-designed experiments and clinical trials are needed to warrant the promising advent of this hydrogel-based biomaterial.
Loss of rpoE Encoding the δ-Factor of RNA Polymerase Impacts Pathophysiology of the Streptococcus pyogenes M1T1 Strain 5448
Authors: Rom Joseph S. , Le Breton Yoann , Islam Emrul , Belew Ashton T. , El-Sayed Najib M. , McIver Kevin S.
Published: August 2022

Streptococcus pyogenes, also known as the Group A Streptococcus (GAS), is a Gram-positive bacterial pathogen of major clinical significance. Despite remaining relatively susceptible to conventional antimicrobial therapeutics, GAS still causes millions of infections and hundreds of thousands of deaths each year worldwide. Thus, a need for prophylactic and therapeutic interventions for GAS is in great demand. In this study, we investigated the importance of the gene encoding the delta (δ) subunit of the GAS RNA polymerase, rpoE, for its impact on virulence during skin and soft-tissue infection. A defined 5448 mutant with an insertionally-inactivated rpoE gene was defective for survival in whole human blood and was attenuated for both disseminated lethality and lesion size upon mono-culture infection in mouse soft tissue. Furthermore, the mutant had reduced competitive fitness when co-infected with wild type (WT) 5448 in the mouse model. We were unable to attribute this attenuation to any observable growth defect, although colony size and the ability to grow at higher temperatures were both affected when grown with nutrient-rich THY media. RNA-seq of GAS grown in THY to late log phase found that mutation of rpoE significantly impacted (>2-fold) the expression of 429 total genes (205 upregulated, 224 downregulated), including multiple virulence and “housekeeping” genes. The arc operon encoding the arginine deiminase (ADI) pathway was the most upregulated in the rpoE mutant and this could be confirmed phenotypically. Taken together, these findings demonstrate that the delta (δ) subunit of RNA polymerase is vital in GAS gene expression and virulence.
Pitahaya Peel: A By-Product with Great Phytochemical Potential, Biological Activity, and Functional Application
Authors: Jimenez-Garcia Sandra N. , Garcia-Mier Lina , Ramirez-Gomez Xóchitl S. , Aguirre-Becerra Humberto , Escobar-Ortiz Alexandro , Contreras-Medina Luis M. , Garcia-Trejo Juan F. , Feregrino-Perez Ana A.
Published: August 2022

Hylocereus spp. present two varieties of commercial interest due to their color, organoleptic characteristics, and nutritional contribution, such as Hylocerous polyrhizus and Selenicerus undatus. The fruit recognized as dragon fruit or Pitahaya is an exotic fruit whose pulp is consumed, while the peel is discarded during the process. Studies indicate that the pulp has vitamin C and betalains, and seeds are rich in essential fatty acids, compounds that can contribute to the prevention of chronic non-communicable diseases (cancer, hypertension, and diabetes). In the present study, polyphenolic compounds, biological activity, and fatty acids present in the peel of the two varieties of pitahaya peel were evaluated, showing as a result that the variety S. undatus had higher antioxidant activity with 51% related to the presence of flavonoids 357 mgRE/g sample and fatty acids (hexadecanoic acid and linoleate) with 0.310 and 0.248 mg AG/g sample, respectively. On the other hand, H. polyrhizuun showed a significant difference in the inhibitory activity of amylase and glucosidase enzymes with 68% and 67%, respectively. We conclude that pitahaya peel has potential health effects and demonstrate that methylated fatty acids could be precursors to betalain formation, as well as showing effects against senescence and as a biological control against insects; in the same way, the peel can be reused as a by-product for the extraction of important enzymes in the pharmaceutical and food industry.
Remediation of Soil Mercury by Modified Vermiculite-Montmorillonite and Its Effect on the Growth of Brassica chinensis L.
Authors: Li Chang , Li Yuchen , Cheng Hua , Jiang Chunlu , Zheng Liugen
Published: August 2022

In this study, the surface of vermiculite-montmorillonite was modified by MnO2 loading. The modified vermiculite-montmorillonite was added to remediate the potentially toxic trace element (PTE) Hg present in soil containing coal gangue. Pot experiments were conducted to analyze and compare the pH values, Hg contents and Hg species present in coal gangue-containing soil, with and without the modified materials added, to determine whether the addition of modified materials had an effect on the growth of Brassica chinensis L. Results showed that with the addition of 35 g·kg−1 modified vermiculite-montmorillonite, the pH of soil increased by a value of 0.79, compared with that in the control group. When 15 g·kg−1 was added, the concentration of Hg in soil decreased by 98.2%. The addition of modified materials promoted the transformation of Hg in soil from a bioavailable form to an unavailable form; that is, the content of the residual form increased. The plant height and biomass of Brassica chinensis L. also increased, which indicated that the addition of modifiers can increase soil productivity, reduce the effects of PTEs on organisms in soil, and promote plant growth. Therefore, the addition of modified vermiculite-montmorillonite can achieve remediation of coal gangue-containing soil.
Biophysical Characterization of the Interaction between a Transport Human Plasma Protein and the 5,10,15,20-Tetra(pyridine-4-yl)porphyrin
Authors: Chaves Otávio Augusto , Iglesias Bernardo A. , Serpa Carlos
Published: August 2022

The interaction between human serum albumin (HSA) and the non-charged synthetic photosensitizer 5,10,15,20-tetra(pyridine-4-yl)porphyrin (4-TPyP) was evaluated by in vitro assays under physiological conditions using spectroscopic techniques (UV-vis, circular dichroism, steady-state, time-resolved, synchronous, and 3D-fluorescence) combined with in silico calculations by molecular docking. The UV-vis and steady-state fluorescence parameters indicated a ground-state association between HSA and 4-TPyP and the absence of any dynamic fluorescence quenching was confirmed by the same average fluorescence lifetime for HSA without (4.76 ± 0.11 ns) and with 4-TPyP (4.79 ± 0.14 ns). Therefore, the Stern–Volmer quenching (KSV) constant reflects the binding affinity, indicating a moderate interaction (104 M−1) being spontaneous (ΔG°= -25.0 kJ/mol at 296 K), enthalpically (ΔH° = -9.31 ± 1.34 kJ/mol), and entropically (ΔS° = 52.9 ± 4.4 J/molK) driven. Binding causes only a very weak perturbation on the secondary structure of albumin. There is just one main binding site in HSA for 4-TPyP (n ≈ 1.0), probably into the subdomain IIA (site I), where the Trp-214 residue can be found. The microenvironment around this fluorophore seems not to be perturbed even with 4-TPyP interacting via hydrogen bonding and van der Waals forces with the amino acid residues in the subdomain IIA.
The Genus Broussonetia: An Updated Review of Phytochemistry, Pharmacology and Applications
Authors: Chen Yueru , Wang Lu , Liu Xue , Wang Fulin , An Ying , Zhao Wei , Tian Jinli , Kong Degang , Zhang Wenru , Xu Yang , Ba Yahui , Zhou Honglei
Published: August 2022

The Broussonetia genus (Moraceae), recognized for its value in many Chinese traditional herbs, mainly includes Broussonetia papyrifera (L.) L’Hér. ex Vent. (BP), Broussonetia kazinoki Siebold (BK), and Broussonetia luzonica (Blanco) Bureau (BL). Hitherto, researchers have found 338 compounds isolated from BP, BK, and BL, which included flavonoids, polyphenols, phenylpropanoids, alkaloids, terpenoids, steroids, and others. Moreover, its active compounds and extracts have exhibited a variety of pharmacological effects such as antitumor, antioxidant, anti-inflammatory, antidiabetic, anti-obesity, antibacterial, and antiviral properties, and its use against skin wrinkles. In this review, the phytochemistry and pharmacology of Broussonetia are updated systematically, after its applications are first summarized. In addition, this review also discusses the limitations of investigations and the potential direction of Broussonetia. This review can help to further understand the phytochemistry, pharmacology, and other applications of Broussonetia, which paves the way for future research.
A Novel Potent Crystalline Chitin Decomposer: Chitin Deacetylase from Acinetobacter schindleri MCDA01
Authors: Yang Guang , Wang Yuhan , Fang Yaowei , An Jia , Hou Xiaoyue , Lu Jing , Zhu Rongjun , Liu Shu
Published: August 2022

Chitosan is a functional ingredient that is widely used in food chemistry as an emulsifier, flocculant, antioxidant, or preservative. Chitin deacetylases (CDAs) can catalyze the hydrolysis of acetyl groups, making them useful in the clean production of chitosan. However, the high inactivity of crystalline chitin catalyzed by CDAs has been regarded as the technical bottleneck of crystalline chitin deacetylation. Here, we mined the AsCDA gene from the genome of Acinetobacter schindleri MCDA01 and identified a member of the uraD_N-term-dom superfamily, which was a novel chitin deacetylase with the highest deacetylation activity. The AsCDA gene was expressed in Escherichia coli BL21 by IPTG induction, whose activity to colloidal chitin, α-chitin, and β-chitin reached 478.96 U/mg, 397.07 U/mg, and 133.27 U/mg, respectively. In 12 h, the enzymatic hydrolysis of AsCDA removed 63.05% of the acetyl groups from α-chitin to prepare industrial chitosan with a degree of deacetylation higher than 85%. AsCDA, as a potent chitin decomposer in the production of chitosan, plays a positive role in the upgrading of the chitosan industry and the value-added utilization of chitin biological resources.
Anti-Cancer Effect of Sesquiterpene and Triterpenoids from Agarwood of Aquilaria sinensis
Authors: Chen Lili , Liu Yunyun , Li Yifei , Yin Wu , Cheng Yongxian
Published: August 2022

Two new guaiane sesquiterpenes, aquisinenoids A and B (1 and 2), two new eudesmane-type sesquiterpenoids, aquisinenoids C and D (3 and 4), one new cucurbitacin, aquisinenoid E (5), and five known cucurbitacins (6–10) were isolated from agarwood of Aquilaria sinensis. The structures of these new compounds, including their absolute configurations, were characterized by spectroscopic and computational methods. The biological evaluation showed that compounds 3 and 9 had an anti-cancer effect on most of the cancer cells at 5 μM, especially in human breast cancer cells. Interestingly, the new compound 3 exhibited more sensitivity on cancer cells than normal cells, highlighting its potential as a novel anti-cancer agent. Mechanically, compound 3 treatment increased the ROS generation and triggered apoptosis of human breast cancer cells.
Nanostructured Electrospun Polycaprolactone—Propolis Mats Composed of Different Morphologies for Potential Use in Wound Healing
Authors: de Figueiredo Agnes Chacor , Anaya-Mancipe Javier Mauricio , de Barros Aline Oliveira da Silva , Santos-Oliveira Ralph , Dias Marcos Lopes , Thiré Rossana Mara da Silva Moreira
Published: August 2022

This study aimed to investigate different types of morphologies obtained using the electrospinning process to produce a material that enables wound healing while performing a controlled release. Using benign solvents, the authors prepared and characterised electrospun polycaprolactone mats loaded with propolis, a popular extract in traditional medicine with potential for skin repair. Different morphologies were obtained from distinct storage periods of the solution before electrospinning to investigate the effect of PCL hydrolysis (average diameters of fibres and beads: 159.2–280.5 nm and 1.9–5.6 μm, respectively). Phytochemical and FTIR analyses of the extract confirmed propolis composition. GPC and viscosity analyses showed a decrease in polymer molecular weight over the storage period (about a 70% reduction over 14 days) and confirmed that it was responsible for the nanostructure diversity. Moreover, propolis acted as a lubricant agent, affecting the spun solutions’ viscosity and the thermal properties and hydrophilicity of the mats. All samples were within the value range of the water vapour transpiration rate of the commercial products (1263.08 to 2179.84 g/m2·day). Even though the presence of beads did not affect the propolis release pattern, an in vitro wound-healing assay showed that propolis-loaded mats composed of beaded fibres increased the cell migration process. Thus, these films could present the potential for use in wound dressing applications.
Non-Pharmacological Treatments of Cognitive Impairment in Multiple Sclerosis: A Review
Authors: Bossa Michela , Manocchio Nicola , Argento Ornella
Published: August 2022

Cognitive impairment (CI) represents a common symptom in patients suffering from multiple sclerosis (MS), which can affect every stage of the disease course. Recent studies seem to support cognitive rehabilitation (CR) for minimizing the CI consequences. We reviewed the currently available evidence on the non-pharmacological approaches to CI, with the aim of giving an overview of the treatments used worldwide, from the traditional methods to the most recent techniques. A search of the literature was conducted on PubMed (articles in English performed in the last five years on humans). A total of 37 articles met our eligibility criteria after screening titles, abstracts and full-text and were divided into three main groups: in-presence interventions; studies performed via tele-rehabilitation and miscellaneous. Despite the great heterogeneity of the intervention and assessment methods, the evidence suggests that a non-pharmacological approach can improve MS-related CI. Cognitive rehabilitation seems effective and well established, as well as the use of computerized CR having the benefit of being even more appealing. Limited conclusions can be drawn on group CR due to the small number of studies focused on this kind of intervention. Some of the innovative approaches (virtual reality, EEG-based neurofeedback, brain stimulation, exercise, diet modification) may play a role in future studies and should be deeply explored.