bluuebunny/crossref_metadata_2025 huggingface dataset:
The Colletotrichum siamense Hydrophobin CsHydr1 Interacts with the Lipid Droplet-Coating Protein CsCap20 and Regulates Lipid Metabolism and Virulence
Authors: Wang Na , Wang Jiyuan , Lu Jingwen , Liu Yu , Xi Yitao , Song Miao , Guan Xiaoling , Li Zhigang , Li Xiao , Zhang Yu , Lin Chunhua , Miao Weiguo
Published: September 2022

Previous studies of the lipid droplet-coating protein Cap20 in Colletotrichum show that it plays a key role in appressorium development and virulence. In this study, the hydrophobin CsHydr1, which contains a signal peptide of 19 amino acids and a hydrophobic domain (HYDRO), was shown to interact with CsCap20 in Colletotrichum siamense. The CsHydr1 deletion mutant showed slightly enhanced mycelial growth, small conidia, slow spore germination and appressoria formation, cell wall integrity and virulence. Like CsCAP20, CsHydr1 is also localized on the lipid droplet surface of C. siamense. However, when CsCap20 was absent, some CsHydr1 was observed in other parts. Quantitative lipid determination showed that the absence of either CsHydr1 or CsCap20 reduced the content of lipids in mycelia and conidia, while the effect of CsCap20 was more obvious; these results suggest that an interaction protein CsHydr1 of CsCap20 is localized on the lipid droplet surface and involved in lipid metabolism, which affects appressorium formation and virulence in C. siamense.
The Microbiome Revolution: New Insights for Personalized Medicine
Authors: Laterza Lucrezia , Mignini Irene
Published: September 2022

The availability of new culture-independent techniques to study microbes led to the explosion of the gut microbiota revolution in recent decades [...]
Study on the Spatial Differences in Land-Use Change and Driving Factors in Tibet
Authors: Wu Chunsheng
Published: September 2022

As the main body of the Qinghai–Tibet Plateau, the Tibet Autonomous Region is an important ecological security barrier for the surrounding areas and even for Asia. However, the ecological environment is very fragile, and slight changes in land use may seriously affect the stability of the ecosystem. Therefore, it is necessary to deeply explore the driving factors of change in the various land-use types to stabilize the ecological structure and function of Tibet. In this paper, the transition matrix, land dynamic degree and Geodetector model are introduced to obtain the land-use change in the whole Tibetan region and its four subregions from 1990 to 2020. Based on the elevation, slope, temperature, precipitation, population and GDP, the driving factors of conversions between land-use types are explored. The results showed that during the study period, farmland, grassland and forest all showed a decreasing trend in area size. The grassland is large in the northwest region and is the main land-use type in Tibet, and its conversion to water area is the largest. The area of construction land has increased significantly, and its occupation of farmland is the largest, especially in the southwest region. The Geodetector results show that there are differences in the driving factors of the conversions between the whole region and each subregion. In the whole region, the increase in precipitation and temperature were the main drivers of unutilized land and grassland-to-water area conversions, whereas the growth of GDP and population were the dominant drivers of built-up land expansion; however, at the subregional scale, the driving effects of topographic and climatic factors in the two conversions were enhanced. In addition, under the implementation of different ecological protection measures, the productivity of vegetation has been improved. Based on the study results, ecological protection and restoration projects can be implemented in a targeted manner by guiding human activities and formulating reasonable plans to achieve the purpose of strengthening the sustainability of land use and protecting the ecological environment regionally.
The Significance of Digital Elevation Models in the Calculation of LS Factor and Soil Erosion
Authors: Michalopoulou Maria , Depountis Nikolaos , Nikolakopoulos Konstantinos , Boumpoulis Vasileios
Published: September 2022

This study focuses on the role of topography in soil erosion modelling by examining the impact of topographic data from various sources on the calculation of the slope length and slope steepness factor (LS). For this purpose, the Pinios dam drainage basin in the Ilia Regional Unit, Western Greece, was selected as a pilot area of this study. Specifically, six Digital Elevation Models (DEM) from four different sources with various resolutions (5, 30, and 90 m) were compared with ground control point (GCP) values to assess their relative vertical accuracy. These DEM were acquired for the calculation of the LS factor by using two different equations. Then the calculated LS factors were implemented in the RUSLE model for the estimation of soil loss. The current study includes a comparative analysis of the elevation, the slopes, the LS factor, and the soil loss. The results showed that the 5 m resolution DEM had the best vertical accuracy, and thus it is considered to be the most suitable DEM for soil erosion modelling. Moreover, the comparison of the DEM elevation values showed high similarity, in contrast to the slope values. In addition, the comparative assessment of the LS and soil loss values calculated from each DEM with the two LS equations revealed a great divergence. It is noticeable that both LS and soil loss results presented higher values for slopes greater than 20°. It is concluded that the comparison of the LS values calculated with the two examined approaches and the use of different DEM with various resolutions and different sources does not change consistently with the increase of DEM grid size and accuracy. Thus, it is very significant in soil erosion modelling to use an LS equation that imports thresholds in its formula to avoid overestimation in soil loss calculations.
Identifying Ecosystem Services Bundles for Ecosystem Services Trade-Off/Synergy Governance in an Urbanizing Region
Authors: Cai Wenbo
Published: September 2022

Ecosystem services (ES) are the contribution of ecosystem structure and function to human well-being, connecting natural and socio-economic systems. ES trade-off/synergy has been one of the critical issues in sustainable environmental governance for guiding and formulating environmental policies. However, science-to-practice framework for ecosystem services trade-off/synergy governance are still rare. This study presents a comprehensive framework for identifying and managing trade-off and synergy of ESs in an urbanizing region. Using Guangdong-Hong Kong-Macao Greater Bay Area (GBA)—one of the fastest urbanizing regions in China—as a case, this study identified major ecosystem service bundles (ESBs) and applied the comprehensive framework to inform ES trade-off/synergy governance. The results showed that there were three stable ESBs in the GBA, and that ESB 1 (high grain production) and ESB 2 (high carbon sequestration) should be increased, and ESB 3 (all ES provision are low) should be increased. Moreover, there was large spatial–temporal change in ESBs in the central area of the GBA during 2000–2015 due to population and land urbanization. This study provides valuable information for sustainable land management and environmental governance in an urbanizing region.
Genomic Approaches to Uncovering the Coevolutionary History of Parasitic Lice
Authors: Johnson Kevin P.
Published: September 2022

Next-generation sequencing technologies are revolutionizing the fields of genomics, phylogenetics, and population genetics. These new genomic approaches have been extensively applied to a major group of parasites, the lice (Insecta: Phthiraptera) of birds and mammals. Two louse genomes have been assembled and annotated to date, and these have opened up new resources for the study of louse biology. Whole genome sequencing has been used to assemble large phylogenomic datasets for lice, incorporating sequences of thousands of genes. These datasets have provided highly supported trees at all taxonomic levels, ranging from relationships among the major groups of lice to those among closely related species. Such approaches have also been applied at the population scale in lice, revealing patterns of population subdivision and inbreeding. Finally, whole genome sequence datasets can also be used for additional study beyond that of the louse nuclear genome, such as in the study of mitochondrial genome fragmentation or endosymbiont function.
Structural Insights into Mouse H-FABP
Authors: Wang Lili , Zhang Haoran , Lv Panjing , Li Yan , Teng Maikun , Liu Yahui , Wu Donghai
Published: September 2022

Intracellular fatty acid-binding proteins are evolutionarily highly conserved proteins. The major functions and responsibilities of this family are the regulation of FA uptake and intracellular transport. The structure of the H-FABP ortholog from mouse (Mus musculus) had not been revealed at the time this study was completed. Thus, further exploration of the structural properties of mouse H-FABP is expected to extend our knowledge of the model animal’s molecular mechanism of H-FABP function. Here, we report the high-resolution crystal structure and the NMR characterization of mouse H-FABP. Our work discloses the unique structural features of mouse H-FABP, offering a structural basis for the further development of small-molecule inhibitors for H-FABP.
The Pre-Discharge Oxygen Uptake Efficiency Slope Predicts One-Year Cardiovascular Events in Acute Decompensated Heart Failure Patients
Authors: Huang I-Ching , Chen Yi-Jen , Chen Chia-Hsin , Huang Wei-Chun , Lin Ko-Long
Published: September 2022

(1) Background: Heart failure is a complex disease leading to functional disability. Cardiopulmonary exercise testing (CPET) is the gold standard in assessing aerobic capacity and formulating function-based prognostic stratification; however, patients with acute heart failure after medical treatment usually remain with markedly reduced exercise capacity, leading to early termination of CPET with submaximal testing results. The current study aimed to assess the cardiorespiratory fitness and characteristics of CPET variables of patients after acute heart failure treatment and determine potential CPET variables with prognostic value. (2) Methods: We recruited patients during hospitalization after management of acute heart failure, and pre-discharge CPET was performed. All enrolled patients were followed for one year for major adverse cardiovascular events (MACE). (3) Results: 85 patients were enrolled, with average left ventricular ejection fraction of 30.52%, and peak oxygen consumption of 10.85 mL/min/kg at baseline. The one-year MACE was 50%. Oxygen uptake efficiency slope (OUES) was a significant event predictor, with lower one-year MACE in those with OUES ≥ 1.25 (p < 0.001). Cox regression analysis showed a 5.421-fold increased risk of MACE in those with OUES < 1.25 (p = 0.004). (4) Conclusions: The current results suggested OUES is a significant prognostic indicator in patients with acute heart failure. This also emphasized the critical role of CPET in patients with heart failure for prognostic stratification.
Synthesis, Characterization, and Structure of Mixed-Ligand Cobalt (II) Complex with N, O Donor Sites
Authors: Mandal Debdas , Haldar Anwesha , Chakraborty Priyanka , Ganguly Rakesh
Published: September 2022

A mononuclear octahedral mixed-ligand cobalt (II) complex [Co(H2L)(PhCOO)2] (1) has been prepared by using H2L (N,N′-dimethyl-N,N′-bi(2-hydroxy-3,5-di methyl benzyl)-ethylenediamine) as a facially coordinating tetradentate ligand with a N2O2 donor center along with sodium benzoate as an ancillary ligand. Complex 1 has been characterized by a single-crystal X-ray diffraction study, as well as by other spectroscopic tools. The complex crystallizes in the monoclinic space group C2 with a = 31.73(3) Å, b = 7.868(3) Å, c = 19.131(15) Å, and β = 125.25(3)°. The single-crystal X-ray diffraction study shows that in the mononuclear cobalt (II) complex [Co(H2L)(PhCOO)2] (1), the metal center adopts an octahedral environment.
N-(1-azido-2-(azidomethyl)butan-2-yl)-4-methylbenzenesulfonamide
Authors: Hajib Sara , Aouine Younas , Faraj Hassane , Alami Anouar
Published: September 2022

A new bi-triazole precursor, N-(1-azido-2-(azidomethyl)butan-2-yl)-4-methylbenzenesulfonamide, was synthesized in two steps from 2-amino-2-ethyl-1,3-propanediol, with an overall yield of 80%. The chemical structures of the products obtained were established based on 1D and 2D NMR, IR spectroscopy, and elemental analysis.
High Electromagnetic Shielding Effect of Carbon Nanotubes/Waterborne Polyurethane Composites Prepared by “Break-Adsorption” Method
Authors: Li Yasen , Shang Yudong , Li Mingyue , Zhang Xiang , He Jiangping
Published: September 2022

In recent years, conductive polymer composites have been widely studied for their electrical conductivity and electromagnetic shielding effects due to their advantages of light weight, simple preparation methods, and structural design versatility. In this study, oxidized multi-walled carbon nanotubes/waterborne polyurethane composites (OCNT/WPU) were prepared by grafting oxidized carbon nanotubes onto polyurethane molecular chains through in situ polymerization, using environmentally friendly waterborne polyurethane as the polymer matrix. Then, the OCNT/WPU structure was broken by high shear force, and the loading of CNTs was increased by adsorption, and a new composite structure was designed (denoted by OCWPU). The structure and morphology of OCNT/WPU and OCWPU were characterized by FT-IR and SEM. The structure and morphology of OCWPU with different multi-walled carbon nanotube loadings (CNTs/OCWPU) were characterized by SEM, Raman. Finally, the electrical conductivity and the electromagnetic shielding properties of the composites were investigated. It was found that after application of high shear force, the structure of OCWPU was disrupted and the surface activity of the material increased. With the increase in CNTs content, CNTs formed a rosette structure in the polyurethane matrix and covered the surface, and its electromagnetic shielding effect in X-bond (8.2–12.4 Ghz) would be able to reach 23 dB at 5% CNTs/OCWPU and 66.5 dB at 50% CNTs/OCWPU to meet the commercial needs. With 50% CNTs/OCWPU, an electrical conductivity of 5.1 S/cm could be achieved. This work provides a novel idea for the structural design of conductive polymer composites, which can achieve greater performance with the same carbon nanotube content.
SEM Analysis of Glued Joints of Thermally Modified Wood Bonded with PUR and PVAc Glues
Authors: Mamoňová Miroslava , Ciglian Dávid , Reinprecht Ladislav
Published: September 2022

This study deals with the scanning electron microscopy (SEM) analyses of the phase interfaces in the glued joints between Norway spruce wood elements thermally modified at 160, 180, 200, and 220 °C/4 h and polyurethane (PUR) and polyvinyl acetate (PVAc) glues with the aim of evaluating various anatomical influences of wood on the quality of joints. Due to cracked regions created in the surface of spruce wood at severe thermal modifications, the penetration depth of glues doubled from 140 to 241 μm for PUR glue, and from 100 to 200 μm for PVAc glue. The thickness of glue lines in joints was apparently higher for PVAc glue, mainly in earlywood regions; however, in joints from thermally modified (TM) woods it increased more apparently for PUR glue from 16.6 to 44.4 μm, probably in connection with formation of micro-bubbles in its structure. The SEM analyses corresponded well with the previous knowledge about lower shear strength of glued joints formed from the more intensively TM spruce elements and mentioned types of glues.
Mechanical Properties of Alkali-Activated Slag Fiber Composites Varying with Fiber Volume Fractions
Authors: Lim Hyeon-Jin , Cho Chang-Geun , You Jang-Yeol , Jeong Jong-Jin
Published: September 2022

The mechanical properties of alkali-activated slag fiber composites (ASFC) were investigated with varying volume fractions of PVA (Polyvinyl alcohol) fibers. Ground granulated blast furnace slag (GGBS) and alkali-activators were used as the main binders instead of cement, which emits a large amount of carbon dioxide during the manufacturing process. The measured slump flow of ASFC showed a high fluidity at a fiber content of 1.5 vol.% or less. The tensile, flexural, and shear strength of ASFC showed higher values as the amount of fiber increased. Compared to the existing high ductility fiber composites showing strain hardening behaviors with a fiber content of 2.0 vol.%, ASFC proved that it could exhibit high ductility characteristics due to multi-microcracks even at low fiber mixing rates of 1.0% and 1.25%. ASFC could be expected to lower the manufacturing cost with a low fiber content and provide improved workability with high fluidity. In addition, when manufacturing structural components using the developed ASFC, it is expected that the amount of fiber could be selected and used according to the required performance.
Characterization of Carbide Precipitation during Tempering for Quenched Dievar Steel
Authors: Xie Yixin , Cheng Xiaonong , Wei Jiabo , Luo Rui
Published: September 2022

Carbide precipitation and coarsening are investigated for quenched Dievar steel during tempering. Lath/lenticular martensite, retained austenite, lower bainite, auto-tempered, and larger spherical carbides are all observed in the as-quenched condition. The carbide precipitation sequence on tempering is ascertained to be: M8C7 + cementite → M8C7 + M2C + M7C3 → M8C7 + M7C3 + M23C6 → M8C7 + M7C3 + M23C6 + M6C; carbides become coarser on tempering, and the sizes for inter-lath carbides increase noticeably with increasing tempering temperatures due to the faster grain boundary diffusion, whereas the sizes for intra-lath carbides remain nearly constant. The rate of coarsening for carbides by tempering at 650 °C is much higher than those by tempering at 550 °C and 600 °C, due to the faster diffusion of alloying elements at higher temperatures.
Minimizing the Forces in the Single Point Incremental Forming Process of Polymeric Materials Using Taguchi Design of Experiments and Analysis of Variance
Authors: Rosca Nicolae , Trzepieciński Tomasz , Oleksik Valentin
Published: September 2022

The aim of the present paper is that of conducting a study on the basis of which the optimal parameters for the manufacturing of polymer parts by means of the single point incremental forming process can be chosen in such a way that the process forces have minimum values. Two polymeric materials with a 3 mm thickness, polyamide and polyethylene, were chosen for the analysis. The other input parameters that were considered were: the punch diameter, the step on vertical direction and the wall angle. The Taguchi method was chosen for the design of experiments. Each of the input parameters, except for the material, were varied on three levels—for the punch diameter: 6 mm, 8 mm and 10 mm; for the step on vertical direction: 0.5 mm, 0.75 mm and 1 mm; and for the wall angle: 50°, 55° and 60°. Forces were measured in the three directions of the coordinate axes and the results were analyzed based on the signal-to-noise ratio and an analysis of variance with the aim of minimizing the values of the forces. Considering the input parameters analyzed, it was concluded that the forces are most influenced by the material, followed by the punch diameter, the step on vertical direction and the wall angle.
Influence of Factors in the Photopolymerization Process on Dental Composites Microhardness
Authors: Maximov Jordan , Dikova Tsanka , Duncheva Galya , Georgiev Georgi
Published: September 2022

The aim of the present paper is to investigate the influence of factors in photopolymerization process that govern microhardness of three types of dental composites—universal (UC), bulk-fill (BC), and flowable (FC). Cylindrical specimens with different thicknesses are made and light cured. The significance of light intensity, irradiation time, and layer thickness on Vickers microhardness is evaluated by experimental design, analysis of variance, and regression analysis. It is found that the main factor influencing the microhardness on the top surface of the three composites is light intensity. The second factor is layer thickness for the UC and FC, while for BC, it is curing time. The third factor is curing time for the first two composites and layer thickness for bulk-fill. The significance of factors’ influence on the microhardness of the bottom surface is the same for the UC and FC, but different for BC. The main factor for the first two composites is layer thickness, followed by curing time and light intensity. For bulk-fill, curing time is main factor, light intensity is second, and layer thickness is last. Different significance of factors influencing the microhardness on top and bottom surfaces of investigated composites is revealed for the first time in the present study.
Comparative Experiment of Abrasion-Corrosion-Sliding Wear Performance of Two Kinds of Low Alloy Wear-Resistant Steel
Authors: Chai Jinrong , Li Guohua
Published: September 2022

There is a serious wear problem in the middle plate of scraper conveyors, which causes the problems of high transportation cost, low efficiency, and a lot of material waste. Therefore, it is necessary to study the wear performance of middle plate materials. A new high-titanium low alloy wear-resistant steel (ZM4-13) and a typical material (NM400) for middle plates are studied in this paper. The findings show that the mass loss of ZM4-13 and NM400 rises with the increase of coal gangue percentage. They do not increase monotonically with the change of pH value, and there is a critical value: the critical value of NM400 is between 6–8, and the critical value of ZM4-13 is between 7–9. When the pH value is less than the critical value, the mass loss decreases with the increase of pH value; when the pH value is greater than the critical value, the mass loss increases with the increase of pH value. Under the condition of high gangue and neutral solutions, ZM4-13 has better wear resistance. Its wear resistance can reach up to 1.09–2.10 times compared with NM400. The in-situ precipitated TiC particles are dispersed in ZM4-13. The high hardness of the TiC precipitation area in ZM4-13 hinders the plowing of hard particles and the plastic deformation of surface materials, so ZM4-13 is more wear-resistant than NM400, especially suitable for the harsh working conditions of coal mine production.
3D RBSM Analysis of Bond Degradation in Corroded Reinforced Concrete as Observed Using Digital Image Correlation
Authors: Avadh Kumar , Nagai Kohei
Published: September 2022

The buildup of corrosion products over a reinforcing bar and associated reduction in rib height lead to degradation of the bond between reinforcement and concrete. The authors have previously used digital image correlation (DIC) to visualize and quantify load-induced cracking at the interface in specimens with varying degrees of corrosion. The results obtained in that study are used here to simulate the post-corrosion local bond behavior. A bond degradation model is incorporated into the discrete analysis tool, 3D Rigid Body Spring Model (RBSM) for the simulation. This analysis method allows the shape of the reinforcing bar to be directly modeled, and concrete cracking behavior is simulated by using a randomly shaped mesh. The magnitude of opening and sliding over the tips of ribs in the simulation, in which the reduction in rib height could not be modeled, is significantly lower than observed in the experiment. The results demonstrate that reduction in rib height is an important factor in post-corrosion behavior, and needs to be included in simulation models. It is also understood that in order to gain a better understanding of local post-corrosion bond behavior, de-bonding between reinforcement and concrete needs to be modeled in a discrete analysis framework.
Wet Etching of Quartz Using a Solution Based on Organic Solvents and Anhydrous Hydrofluoric Acid
Authors: Wan Yang , Luan Xinghe , Zhou Longzao , Wu Fengshun
Published: September 2022

The quartz-crystal resonator is the core device for frequency control in modern communication systems and network technology. At present, in modern resonator blanks manufacturing, BOE solution is usually used as the etching solution, but its etching rate is relatively volatile, and the surface morphology of the blanks is prone to defects after etching, which brings certain difficulties to the deep-etching process of the wafer. To solve the above challenges, this paper systematically compares a BOE solution and anhydrous etching solution in terms of etching rate, surface morphology, and electrical properties of the blanks after etching. Seven groups of blanks were etched using different etching solutions with different etching conditions to verify their effect on the surface morphology and electrical properties of quartz blanks. The experimental results suggest that the application of anhydrous etching solution has achieved better surface morphology and electrical properties and can be more suitable for application in batch manufacturing. In general, when using anhydrous etching solution, it is possible to reduce surface roughness by up to 70% and equivalent resistance by 32%, and the etch rate is almost 10 times lower than BOE solution under the same temperature, which is more conducive to the rate control of wafers in the etching process.
Vibro-Impact Response Analysis of Collision with Clearance: A Tutorial
Authors: Xu Yongjie , Tian Yu , Li Qiyu , Li Yanbin , Zhang Dahai , Jiang Dong
Published: September 2022

A collision with clearance causes obvious nonlinearity in structures, and dynamic response analysis plays an important role in predicting the mechanical performance of the structure. The general form of the nonlinear dynamic equation of a structure and the clearance modeling method are introduced, and the clearance-caused nonlinear term is expressed by nonlinear impact forces. Different clearance collision models of local nonlinear structures are presented. The relationships between different impact forces and clearances are analyzed by two rigid sphere models. The solution methods of the nonlinear dynamic equation are compared by a vibro-impact response, such as the Newmark-β method combined with the Newton–Raphson method, generalized α method and precise integration method. The single degree of freedom model is adopted to compare the efficiency of the different numerical integration algorithms. Taking the beam structure model as a case study, the accurate nonlinear collision model with clearance is established by using the impact force model with high accuracy, and the accuracy of the model is verified by comparing the reference model with the numerical model.
Magnetic Field Analysis and Performance Optimization of Dual-Rotor Hybrid Excitation Generator for Automobile
Authors: Yan Shilong , Zhang Xueyi , Zhang Jun , Zhang Yufeng , Xu Mingjun , Gao Ting , Hua Sizhan
Published: September 2022

Aiming at the current problems of low excitation efficiency and poor reliability of single-rotor hybrid excitation generators, the large axial length of dual-rotor structure, and difficulty in magnetic field analysis, a new type of the dual-rotor hybrid excitation generator topology with high power density is proposed, with two rotors side-by-side coaxial, sharing a set of armature windings, and the magnetic fields do not interfere with each other, so the magnetic field analysis and optimization of the two rotors can be carried out separately. The magnetic density distribution of the new permanent magnet (PM) claw pole rotor is analyzed by the joint application of the equivalent magnetic circuit method and the equivalent magnetic network method, which ensures the simplicity of calculation and improves the calculation accuracy. The multi-objective optimization of the key structural parameters is carried out based on the Latin hypercube sampling–Pareto frontier solution method. The subdomain method is improved by segmented equivalence, the unique solution of the salient-pole rotor magnetic field is obtained, and the multi-objective optimization of the salient-pole rotor is used by the particle swarm algorithm. The trial prototype was experimental, and the results showed that the output characteristics of the optimized hybrid excitation generator were significantly improved, and the overall performance of the generator was improved.
Conceptualization and Implementation of a Reconfigurable Unmanned Ground Vehicle for Emulated Agricultural Tasks
Authors: Saeed Raza A. , Tomasi Giacomo , Carabin Giovanni , Vidoni Renato , von Ellenrieder Karl D.
Published: September 2022

Small-to-medium sized systems able to perform multiple operations are a promising option for use in agricultural robotics. With this in mind, we present the conceptualization and implementation of a versatile and modular unmanned ground vehicle prototype, which is designed on top of a commercial wheeled mobile platform, in order to test and assess new devices, and motion planning and control algorithms for different Precision Agriculture applications. Considering monitoring, harvesting and spraying as target applications, the developed system utilizes different hardware modules, which are added on top of a mobile platform. Software modularity is realized using the Robot Operating System (ROS). Self- and ambient-awareness, including obstacle detection, are implemented at different levels. A novel extended Boundary Node Method is used for path planning and a modified Lookahead-based Line of Sight guidance algorithm is used for path following. A first experimental assessment of the system’s capabilities in an emulated orchard scenario is presented here. The results demonstrate good path-planning and path-following capabilities, including cases in which unknown obstacles are present.
Magnetic Nanoparticles: An Overview for Biomedical Applications
Authors: Mittal Ashi , Roy Indrajit , Gandhi Sona
Published: September 2022

The use of magnetic nanoparticles has greatly expanded for numerous biomedical applications over the past two decades due to their high surface area, size-dependent superparamagnetic properties, precision tunability, and easy surface modification. Magnetic nanoparticles can be engineered and manipulated with other nanoparticles and functional compounds to form multi-modal systems useful in theragnosis. However, superior biocompatibility, high loading efficacy, regulated drug release, and in vitro and in vivo stability are necessary for the efficient incorporation of these nanoparticles into physiological systems. In recent years, considerable advancements have been made and reported both in synthesis and application, given the broad range of biomedical-related prospective uses of magnetic nanoparticles. Here, in this review, we have highlighted some essential works, specifically related to the application of magnetic nanoparticles in drug delivery, magnetic hyperthermia, magnetic resonance imaging, magnetic particle imaging, biosensors, and tissue engineering.
Cloze-Style Data Augmentation for Few-Shot Intent Recognition
Authors: Zhang Xin , Jiang Miao , Chen Honghui , Chen Chonghao , Zheng Jianming
Published: September 2022

Intent recognition aims to identify users’ potential intents from their utterances, which is a key component in task-oriented dialog systems. A real challenge, however, is that the number of intent categories has grown faster than human-annotated data, resulting in only a small amount of data being available for many new intent categories. This lack of data leads to the overfitting of traditional deep neural networks on a small amount of training data, which seriously affects practical applications. Hence, some researchers have proposed few-shot learning should address the data-scarcity issue. One of the efficient methods is text augmentation, which always generates noisy or meaningless data. To address these issues, we propose leveraging the knowledge in pre-trained language models and constructed the cloze-style data augmentation (CDA) model. We employ unsupervised learning to force the augmented data to be semantically similar to the initial input sentences and contrastive learning to enhance the uniqueness of each category. Experimental results on CLINC-150 and BANKING-77 datasets show the effectiveness of our proposal by its beating of the competitive baselines. In addition, we conducted an ablation study to verify the function of each module in our models, and the results illustrate that the contrastive learning module plays the most important role in improving the recognition accuracy.
Asymptotics of Solutions to a Differential Equation with Delay and Nonlinearity Having Simple Behaviour at Infinity
Authors: Kashchenko Alexandra
Published: September 2022

In this paper, we study nonlocal dynamics of a nonlinear delay differential equation. This equation with different types of nonlinearities appears in medical, physical, biological, and ecological applications. The type of nonlinearity in this paper is a generalization of two important for applications types of nonlinearities: piecewise constant and compactly supported functions. We study asymptotics of solutions under the condition that nonlinearity is multiplied by a large parameter. We construct all solutions of the equation with initial conditions from a wide subset of the phase space and find conditions on the parameters of equations for having periodic solutions.
On Two Outer Independent Roman Domination Related Parameters in Torus Graphs
Authors: Gao Hong , Liu Xing , Guo Yuanyuan , Yang Yuansheng
Published: September 2022

In a graph G=(V,E), where every vertex is assigned 0, 1 or 2, f is an assignment such that every vertex assigned 0 has at least one neighbor assigned 2 and all vertices labeled by 0 are independent, then f is called an outer independent Roman dominating function (OIRDF). The domination is strengthened if every vertex is assigned 0, 1, 2 or 3, f is such an assignment that each vertex assigned 0 has at least two neighbors assigned 2 or one neighbor assigned 3, each vertex assigned 1 has at least one neighbor assigned 2 or 3, and all vertices labeled by 0 are independent, then f is called an outer independent double Roman dominating function (OIDRDF). The weight of an (OIDRDF) OIRDF f is the sum of f(v) for all v∈V. The outer independent (double) Roman domination number (γoidR(G)) γoiR(G) is the minimum weight taken over all (OIDRDFs) OIRDFs of G. In this article, we investigate these two parameters γoiR(G) and γoidR(G) of regular graphs and present lower bounds on them. We improve the lower bound on γoiR(G) for a regular graph presented by Ahangar et al. (2017). Furthermore, we present upper bounds on γoiR(G) and γoidR(G) for torus graphs. Furthermore, we determine the exact values of γoiR(C3□Cn) and γoiR(Cm□Cn) for m≡0(mod4) and n≡0(mod4), and the exact value of γoidR(C3□Cn). By our result, γoidR(Cm□Cn)≤5mn/4 which verifies the open question is correct for Cm□Cn that was presented by Ahangar et al. (2020).
Efficient Estimation and Inference in the Proportional Odds Model for Survival Data
Authors: Huang Xifen , Xiong Chaosong , Jiang Tao , Lu Junfeng , Xu Jinfeng
Published: September 2022

In modeling time-to-event data with long-term survivors, the proportional hazards model is widely used for its easy and direct interpretation as well as the flexibility to accommodate the past information and allow time-varying predictors. This becomes most relevant when the mortality of individuals converges with time, and the estimation and inference based upon the proportional odds model can often yield more accurate and reasonable results than the classical Cox’s proportional hazards model. Along with the fast development of the data science technologies, computational challenges for survival data with increasing sample size and diverging parameter dimension exist. Currently, existing methods for analyzing such data are computationally inconvenient. In this paper, we propose efficient computational methods for analyzing survival data in the proportional odds model, where the nonparametric maximum likelihood approach is combined with the minorization-maximization (MM) algorithm and the regularization scheme to yield fast and accurate estimation and inferential procedures. The illustration of the methodology using extensive simulation studies and then the application to the Veterans’ Administration lung cancer data is also given.
Comparative Study of Electrically Excited Conventional and Homopolar Synchronous Motors for the Traction Drive of a Mining Dump Truck Operating in a Wide Speed Range in Field-Weakening Region
Authors: Prakht Vladimir , Dmitrievskii Vladimir , Kazakbaev Vadim , Anuchin Alecksey
Published: September 2022

A synchronous homopolar motor (SHM) has a salient pole passive rotor, an excitation winding located on the stator, and no permanent magnets, which ensures high reliability and makes this type of motor a good alternative to motors traditionally used in traction drives. However, there is no comparison between SHMs and conventional brushed synchronous machines for traction applications in the literature. In this paper, the performances of a wound rotor synchronous machine (WRSM) and SHM are theoretically compared at the operating points of a 370 kW dump mining truck drive traction curve that has a 10:1 constant power range in the field weakening region. The nine-phase motors under comparison have the same outer diameter of the stator lamination. Before comparison, both motor designs are optimized using the Nelder–Mead method to minimize the semiconductor inverter rated current and the operating cycle power loss. The main advantages of the WRSM, which was designed, are reduction in stator length, smaller losses, and smaller inverter. The reduction in the total stator length was by 1.23 times taking into account the winding end parts as well. Losses were reduced by 1.21 times for the same radius of the stator lamination. Finally, the cost of power modules of the inverter was decreased by 1.4 times. SHM is more reliable since its rotor does not have an excitation winding and a diode rectifier, as in a WRSM with a brushless exciter. In addition, SHM provides lower consumption of copper, which reduces the total mass and cost of active materials. This article also introduces a new term, “inverter utilization factor”, which can be useful, more informative than motor power factor, when comparing traction drives with different types of motors.
A New Parameter Choice Strategy for Lavrentiev Regularization Method for Nonlinear Ill-Posed Equations
Authors: George Santhosh , Padikkal Jidesh , Remesh Krishnendu , Argyros Ioannis K.
Published: September 2022

In this paper, we introduced a new source condition and a new parameter-choice strategy which also gives the known best error estimate. To obtain the results we used the assumptions used in earlier studies. Further, we studied the proposed new parameter-choice strategy and applied it to the method (in the finite-dimensional setting) considered in George and Nair (2017).
The Improved Stability Analysis of Numerical Method for Stochastic Delay Differential Equations
Authors: Zhang Yu , Zhang Enying , Li Longsuo
Published: September 2022

In this paper, the improved split-step θ method, named the split-step composite θ method, is proposed to study the mean-square stability for stochastic differential equations with a fixed time delay. Under the global Lipschitz and linear growth conditions, it is proved that the split-step composite θ method with θ≥0.5 shows mean-square stability. An approach to improving numerical stability is illustrated by choices of parameters of this method. Some numerical examples are presented to show the accordance between the theoretical and numerical results.
From Multi- to Univariate: A Product Random Variable with an Application to Electricity Market Transactions: Pareto and Student’s t-Distribution Case
Authors: Adamska Julia , Bielak Łukasz , Janczura Joanna , Wyłomańska Agnieszka
Published: September 2022

Multivariate modelling of economics data is crucial for risk and profit analyses in companies. However, for the final conclusions, a whole set of variables is usually transformed into a single variable describing a total profit/balance of company’s cash flows. One of the possible transformations is based on the product of market variables. Thus, in this paper, we study the distribution of products of Pareto or Student’s t random variables that are ubiquitous in various risk factors analysis. We review known formulas for the probability density functions and derive their explicit forms for the products of Pareto and Gaussian or log-normal random variables. We also study how the Pareto or Student’s t random variable influences the asymptotic tail behaviour of the distribution of their product with the Gaussian or log-normal random variables and discuss how the dependency between the marginal random variables of the same type influences the probabilistic properties of the final product. The theoretical results are then applied for an analysis of the distribution of transaction values, being a product of prices and volumes, from a continuous trade on the German intraday electricity market.
DExMA: An R Package for Performing Gene Expression Meta-Analysis with Missing Genes
Authors: Villatoro-García Juan Antonio , Martorell-Marugán Jordi , Toro-Domínguez Daniel , Román-Montoya Yolanda , Femia Pedro , Carmona-Sáez Pedro
Published: September 2022

Meta-analysis techniques allow researchers to jointly analyse different studies to determine common effects. In the field of transcriptomics, these methods have gained popularity in recent years due to the increasing number of datasets that are available in public repositories. Despite this, there is a limited number of statistical software packages that implement proper meta-analysis functionalities for this type of data. This article describes DExMA, an R package that provides a set of functions for performing gene expression meta-analyses, from data downloading to results visualization. Additionally, we implemented functions to control the number of missing genes, which can be a major issue when comparing studies generated with different analytical platforms. DExMA is freely available in the Bioconductor repository.
Soliton Solutions of Klein–Fock–Gordon Equation Using Sardar Subequation Method
Authors: Rehman Hamood Ur , Iqbal Ifrah , Subhi Aiadi Suhad , Mlaiki Nabil , Saleem Muhammad Shoaib
Published: September 2022

The Klein–Fock–Gordon equation (KFGE), defined as the equation of relativistic wave related to NLEEs, has numerous implications for energy particle physics and is useful as a model for several types of matter, with deviation in the basic stuffs of particles and in crystals. In this work, the Sardar subequation method (SSM) is used for finding the solution of this KFGE. The advantage of SSM is that it provides many different kinds of solitons, such as dark, bright, singular, periodic singular, combined dark–singular and combined dark–bright solitons. The results show that the SSM is very reliable, simple and can be functionalized to other nonlinear equations. It is verified that all the attained solutions are stable by modulation instability process. To enhance the physical description of solutions, some 3D, contour and 2D graphs are plotted by taking precise values of parameters using Maple 18.
A Bayesian Change Point Analysis of the USD/CLP Series in Chile from 2018 to 2020: Understanding the Impact of Social Protests and the COVID-19 Pandemic
Authors: de la Cruz Rolando , Meza Cristian , Narria Nicolás , Fuentes Claudio
Published: September 2022

Exchange rates are determined by factors such as interest rates, political stability, confidence, the current account on balance of payments, government intervention, economic growth and relative inflation rates, among other variables. In October 2019, an increased climate of citizen discontent with current social policies resulted in a series of massive protests that ignited important political changes in Chile. This event along with the global COVID-19 pandemic were two major factors that affected the value of the US dollar and produced sudden changes in the typically stable USD/CLP (Chilean Peso) exchange rate. In this paper, we use a Bayesian approach to detect and locate change points in the currency exchange rate process in order to identify and relate these points with the important dates related to the events described above. The implemented method can successfully detect the onset of the social protests, the beginning of the COVID-19 pandemic in Chile and the economic reactivation in the US and Europe. In addition, we evaluate the performance of the proposed MCMC algorithms using a simulation study implemented in Python and R.
Force Tracking Impedance Control of Hydraulic Series Elastic Actuators Interacting with Unknown Environment
Authors: Nie Yong , Liu Jiajia , Liu Gang , Lyu Litong , Li Jie , Chen Zheng
Published: September 2022

Force tracking control for hydraulic series elastic actuators (SEAs) is the demand in robots interacting with the surrounding world. However, the inherent nonlinearities and uncertainties of the hydraulic system, as well as the unknown environment, make it difficult to achieve precise contact force control of hydraulic SEAs. Therefore, in this study, force tracking impedance control of hydraulic SEAs is developed considering interaction with an unknown environment in which the force tracking performance can be guaranteed in theory. Based on the typical force tracking impedance frame, the force tracking performance is improved by introducing backstepping control into the inner position controller to deal with the high-order nonlinear dynamics of the hydraulic SEA. In addition, the environment parameters are also estimated online by the adaptive method. Finally, comparative simulation is conducted with different interacting environments, which verifies the advantages of the proposed method.
Fractional-Order Multivariable Adaptive Control Based on a Nonlinear Scalar Update Law
Authors: Yan Fang , Hou Xiaorong , Tian Tingting
Published: September 2022

This paper proposes a new fractional-order model reference adaptive control (FOMRAC) framework for a fractional-order multivariable system with parameter uncertainty. The designed FOMRAC scheme depends on a fractional-order nonlinear scalar update law. Specifically, the scalar update law does not change as the input–output dimension changes. The main advantage of the proposed adaptive controller is that only one parameter online update is needed such that the computational burden in the existing FOMRAC can be relieved. Furthermore, we show that all signals in this adaptive scheme are bounded and the mean value of the squared norm of the error converges to zero. Two illustrative numerical examples are presented to demonstrate the efficiency of the proposed control scheme.
h-Almost Ricci–Yamabe Solitons in Paracontact Geometry
Authors: De Uday Chand , Khan Mohammad Nazrul Islam , Sardar Arpan
Published: September 2022

In this article, we classify h-almost Ricci–Yamabe solitons in paracontact geometry. In particular, we characterize para-Kenmotsu manifolds satisfying h-almost Ricci–Yamabe solitons and 3-dimensional para-Kenmotsu manifolds obeying h-almost gradient Ricci–Yamabe solitons. Then, we classify para-Sasakian manifolds and para-cosymplectic manifolds admitting h-almost Ricci–Yamabe solitons and h-almost gradient Ricci–Yamabe solitons, respectively. Finally, we construct an example to illustrate our result.