bluuebunny/crossref_metadata_2025 huggingface dataset:
Decomposing Perfect Readings
Authors: Zhao Ruoying
Published: September 2022

The previous literature established the set of ‘perfect’ readings, including experiential/existential, resultative, recent past, hot news, the Present Perfect Puzzle, the lifetime effect, and the lack of narrative progression. On the other hand, it has been noted that the present perfect in some languages other than English, as well as similar tense/aspect constructions in other languages, falls into the category of a ‘general-purpose past perfective’, namely a tense-aspect constructionsharing some properties with the English present perfect while not being subject to constraints such as the lifetime effect and the Present Perfect Puzzle. In this paper, I propose that the general-purpose past perfectives are presuppositionally neutral tense/aspect constructions that allow the standard past perfective reading. If a language has presuppositionally stronger alternatives for the past perfective (presupposing anaphoricity, uniqueness, etc.), by the Presupposed Ignorance Principle (PIP), the presuppositionally neutral past perfective form will be felicitous only if the presuppositionally stronger alternatives cannot be used. Otherwise, the presuppositionally neutral past perfective will behave like a general-purpose past perfective in the above sense. I argue that this competition is the source of many of the perfect readings observed. I further argue that the cross-linguistic variation in this respect follows from the available alternatives languages have. I illustrate this idea with three groups of languages: (i) English; (ii) French, German, Italian; and (iii) Mandarin Chinese, each illustrating a different set of alternatives available, in both the temporal and aspectual domains. This analysis allows me to decompose various perfect readings that come from different sources and make better predictions regarding which of these readings a tense/aspect construction in a given language has.
The Molecular Network behind Volatile Aroma Formation in Pear (Pyrus spp. Panguxiang) Revealed by Transcriptome Profiling via Fatty Acid Metabolic Pathways
Authors: Li Huiyun , Quan Jine , Rana Sohel , Wang Yanmei , Li Zhi , Cai Qifei , Ma Shuhong , Geng Xiaodong , Liu Zhen
Published: September 2022

Pears are popular table fruits, grown and consumed worldwide for their excellent color, aroma, and taste. Volatile aroma is an important factor affecting fruit quality, and the fatty acid metabolism pathway is important in synthesizing volatile aromas. Most of the white pear varieties cultivated in China are not strongly scented, which significantly affects their overall quality. Panguxiang is a white pear cultivar, but its aroma has unique components and is strong. The study of the mechanisms by which aroma is formed in Panguxiang is, therefore, essential to improving the quality of the fruit. The study analyzed physiological and transcriptome factors to reveal the molecular network behind volatile aroma formation in Panguxiang. The samples of Panguxiang fruit were collected in two (fruit development at 60, 90, 120, and 147 days, and fruit storage at 0, 7, 14, 21, and 28 days) periods. A total of nine sample stages were used for RNA extraction and paired-end sequencing. In addition, RNA quantification and qualification, library preparation and sequencing, data analysis and gene annotation, gene co-expression network analysis, and validation of DEGs through quantitative real-time PCR (qRT-;PCR) were performed in this study. The WGCNA identified yellow functional modules and several biological and metabolic pathways related to fatty acid formation. Finally, we identified seven and eight hub genes in the fatty acid synthesis and fatty acid metabolism pathways, respectively. Further analysis of the co-expression network allowed us to identify several key transcription factors related to the volatile aroma, including AP2/ERF-ERF, C3H, MYB, NAC, C2H2, GRAS, and Trihelix, which may also be involved in the fatty acid synthesis. This study lays a theoretical foundation for studying volatile compounds in pear fruits and provides a theoretical basis for related research in other fruits.
Analysis of Maxillary First Molar Derotation with Invisalign Clear Aligners in Permanent Dentition
Authors: Lione Roberta , Paoloni Valeria , De Razza Francesca Chiara , Pavoni Chiara , Cozza Paola
Published: September 2022

The objective of this study was to examine the distal rotation of mesial rotated maxillary first permanent molars in a sample of Class II dental malocclusion adult patients treated with Invisalign Clear Aligners (CA). Forty patients (20 males, 20 females, 22.4 ± 3.9 years) were included in the study sample (Department of Orthodontics of University of Rome “Tor Vergata”). Inclusion criteria were: Caucasian ancestry, complete permanent dentition with fully erupted upper second molars, Class II molar relationship, absence of tooth or craniofacial anomalies or caries and periodontal diseases. Pre-treatment (T1), post-treatment (T2) digital casts, and final ClinCheck simulation models (T2CC) were analysed. To measure the rotation of maxillary first molars, Henry’s angle (H°) was evaluated. Maxillary first molars with an H° > 11° were considered mesio-rotated (in total 59 teeth). The treatment CA protocol included disto-rotation without distalization movements. At T1, T2 and T2CC five measurements on the collected dental casts were analysed: Henry’s angle (H°); mesial buccal expansion (ME); distal buccal expansion (DE); mesial buccal sagittal (MS); and distal buccal sagittal (DS). A comparison between the results of T2-T1 and T2CC-T2 was performed using a paired t-test. The differences between T2-T1 highlighted a significant distal rotation of the maxillary first molars (−7.4°) and an expansion movement of 2.20 mm for ME and 1.50 mm for DE. In the post-treatment, the mesial buccal cusps shifted of 1.0 mm, while the distal buccal cusps showed a distal movement of 0.9 mm. Analysing the H° comparison between T2CC-T2, the difference was −1.1°. The T2CC-T2 comparison in the sagittal plane showed a difference of 0.9 mm for the MS and 0.7 mm for the DS. The accuracy was 82% for molar derotation movement. In conclusion, CA provides the upper arch expansion associated with the upper first molars’ distal rotation. These movements provide 2 mm of improvement in arch perimeter and molar intercuspation.
Resistance of Bacteria toward 475 nm Blue Light Exposure and the Possible Role of the SOS Response
Authors: Metzger Magdalena , Hacobian Ara , Karner Lisa , Krausgruber Leonie , Grillari Johannes , Dungel Peter
Published: September 2022

The increase in antibiotic resistance represents a major global challenge for our health systems and calls for alternative treatment options, such as antimicrobial light-based therapies. Blue light has shown promising results regarding the inactivation of a variety of microorganisms; however, most often, antimicrobial blue light (aBL) therapy is performed using wavelengths close to the UV range. Here we investigated whether inactivation was possible using blue light with a wavelength of 475 nm. Both Gram-positive and -negative bacterial strains were treated with blue light with fluences of 7.5–45 J/cm2. Interestingly, only some bacterial strains were susceptible to 475 nm blue light, which was associated with the lack of RecA, i.e., a fully functional DNA repair mechanism. We demonstrated that the insertion of the gene recA reduced the susceptibility of otherwise responsive bacterial strains, indicating a protective mechanism conveyed by the bacterial SOS response. However, mitigating this pathway via three known RecA inhibiting molecules (ZnAc, curcumin, and Fe(III)-PcTs) did not result in an increase in bactericidal action. Nonetheless, creating synergistic effects by combining a multitarget therapy, such as aBL, with an RecA targeting treatment could be a promising strategy to overcome the dilemma of antibiotic resistance in the future.
Olive Leaf Extract Attenuates Chlorpyrifos-Induced Neuro- and Reproductive Toxicity in Male Albino Rats
Authors: Hassan Arwa A. , Bel Hadj Salah Karima , Fahmy Esraa M. , Mansour Doaa A. , Mohamed Sally A. M. , Abdallah Asmaa A. , Ashkan Mada F. , Majrashi Kamlah Ali , Melebary Sahar J. , El-Sheikh El-Sayed A. , El-Shaer Nashwa
Published: September 2022

Chlorpyrifos (CPF) is a common organophosphorus insecticide. It is associated with negative consequences such as neurotoxicity and reproductive injury. This study aimed to observe the ability of olive leaf extract to attenuate chlorpyrifos toxicity, which induced neuro- and reproductive toxicity in male albino rats. Olive leaf extract (OLE) exhibits potent antioxidant and antiapoptotic properties. Twenty-two mature male rats were divided into four groups: control (saline), CPF (9 mg/kg), OLE (150 mg/kg), and CPF + OLE. Treatment was administered orally for 80 days. The CPF significantly reduced serum sex hormones, sperm counts and motility, high oxidants (MDA), and depleted antioxidants (GSH, SOD, TAC) in the brain and testes homogenate; additionally, it decreased serum AChE and brain neurotransmitters, increased Bax, decreased Bcl-2, and boosted caspase-3 immune expression in neural and testicular cells. Immunological expression of Ki 67 in the cerebrum, cerebellum, choroid plexus, and hippocampus was reduced, and α-SMA in testicular tissue also decreased. Histopathological findings were consistent with the above impacts. OLE co-administration significantly normalized all these abnormalities. OLE showed significant protection against neural and reproductive damage caused by CPF.
Adulthood Psychosocial Disadvantages and Risk of Hypertension in U.S. Workers: Effect Modification by Adverse Childhood Experiences
Authors: Matthews Timothy A. , Zhu Yifang , Robbins Wendie , Rezk-Hanna Mary , Macey Paul M. , Song Yeonsu , Li Jian
Published: September 2022

Hypertension is a key driver of cardiovascular diseases. However, how stressors contribute to the development of hypertension remains unclear. The objective of this study was to examine prospective associations of adverse childhood experiences (ACEs) and adulthood psychosocial disadvantages (APDs) with incident hypertension. Data were from the Mid-life in the United States (MIDUS) study, a national, population-based, prospective cohort study. ACEs were examined via retrospective reports, and APDs including work stress and social isolation were assessed using survey measures. Incident hypertension was defined based on self-reported physician diagnosis. Baseline data were collected in 1995, with follow-up in 2004–2006 and 2013–2014. Cox proportional hazards regression was applied to assess prospective associations of ACEs and APDs with incident hypertension in 2568 workers free from hypertension at baseline. After adjustment for covariates, baseline APDs were associated with increased incident hypertension (aHR and 95% CI = 1.48 [1.09, 2.01]) during a 20-year follow-up, whereas ACEs showed null associations. Moreover, a moderating effect by ACEs was observed—the effect of APDs on risk of hypertension was stronger when ACEs were present (aHR and 95% CI = 1.83 [1.17, 2.86]). These findings underscore the importance of psychosocial stressors as nontraditional risk factors of cardiometabolic disorders.
Impact of Second-Tier Container Port Facilities on Drayage Operation
Authors: Shiri Samaneh , Huynh Nathan , Smith Daniel , Harder Frank
Published: September 2022

Background: An increasing number of container and chassis staging, “dray-off”, drop yard, and depot facilities are being established outside of North American marine container terminals. The increased use of these “second-tier” facilities implies that there must be some capacity, delivery time, service, or reliability benefit that offset the additional cost and complexity. Methods: This paper builds on the previously developed integrated drayage scheduling model to determine the impact of second-tier port facilities on drayage operation. It modifies the previously developed model by incorporating the following features: (1) trucks do not have to wait at customers’ locations during the import unloading and export loading operations; (2) drayage operations can include a drop yard (i.e., second-tier facility) for picking up or/and dropping off loaded containers outside the marine container terminal; and (3) a customer is allowed to request any of the following jobs: pick up an empty container, pick up a loaded container, drop off an empty container, and drop off a loaded container. Results: The results indicated that by moving the location of import pickup and export delivery from inside the marine container terminal to a location outside the terminal, the efficiency of drayage operation could increase. Additionally, when import pickup and export delivery take place inside the marine container terminal, the most efficient location for the chassis yard and empty container depot is inside the terminal. However, when the location of import pickup and/or export delivery are outside the terminal, the most efficient location for the chassis yard and empty container depot is also outside the terminal. Conclusions: The modeling results suggest that in addition to adding reserved capacity for marine terminals or as buffers to reconcile the preferred delivery times of importers, the second-tier facilities could also yield operational savings. However, the potential drayage efficiencies depend heavily on shorter queuing and turn time at these less-complex facilities compared to marine container terminals. Lastly, the modeling results suggest that the observed evolution of North American marine container terminals from self-contained entities into multi-tier systems is likely to continue to add additional capacities to accommodate container trade growth. This finding has important implications for regions and communities concerned over the impact of growing container ports.
Cyclic Fatigue Resistance of Glide Path Rotary Files: A Systematic Review of in Vitro Studies
Authors: Ashkar Israa , Sanz José Luis , Forner Leopoldo
Published: September 2022

The aim of the present systematic review was to perform a qualitative synthesis of in vitro studies that assess the cyclic fatigue resistance of rotary glide path (GP) files of endodontic applications. Systematic electronic searches were performed in the Medline, Embase, Scopus, SciELO, and Web of Science databases on 15 February 2022, and were last updated on 1 April In vitro studies that evaluated and compared the cyclic fatigue resistance of at least one rotary GP file system with another rotary GP file system were included. A total of 25 studies were included in the qualitative synthesis. All studies assessing the difference in the cyclic fatigue resistance between continuous and reciprocating rotation in rotary glide path files found that the latter resulted in a significantly higher cyclic fatigue resistance, as evidenced by a higher number of cycles until fracture and/or time until fracture. Within the limitations of this review and the in vitro nature of the included studies, the results indicate that the cyclic fatigue resistance of rotary GP files may be influenced by several intrinsic factors of the files, such as their taper, cross-sectional design, alloy properties, kinematics, and external factors, such as the curvature and radius at which the file is activated, the irrigation or lubricant used, and the temperature.
Heparin-Loaded Alginate Hydrogels: Characterization and Molecular Mechanisms of Their Angiogenic and Anti-Microbial Potential
Authors: Nawaz Ayesha , Zaman Safi Sher , Sikandar Shomaila , Zeeshan Rabia , Zulfiqar Saima , Mehmood Nadia , Alobaid Hussah M. , Rehman Fozia , Imran Muhammad , Tariq Muhammad , Ali Abid , Emran Talha Bin , Yar Muhammad
Published: September 2022

Background: Chronic wounds continue to be a global concern that demands substantial resources from the healthcare system. The process of cutaneous wound healing is complex, involving inflammation, blood clotting, angiogenesis, migration and remodeling. In the present study, commercially available alginate wound dressings were loaded with heparin. The purpose of the study was to enhance the angiogenic potential of alginate wound dressings and analyze the antibacterial activity, biocompatibility and other relevant properties. We also aimed to conduct some molecular and gene expression studies to elaborate on the mechanisms through which heparin induces angiogenesis. Methods: The physical properties of the hydrogels were evaluated by Fourier transform infrared spectroscopy (FTIR). Swelling ability was measured by soaking hydrogels in the Phosphate buffer at 37 °C, and cell studies were conducted to evaluate the cytotoxicity and biocompatibility of hydrogels in NIH3T3 (fibroblasts). Real-time PCR was conducted to check the molecular mechanisms of heparin/alginate-induced angiogenesis. The physical properties of the hydrogels were evaluated by Fourier transform infrared spectroscopy (FTIR). Results: FTIR confirmed the formation of heparin-loaded alginate wound dressing and the compatibility of both heparin and alginate. Among all, 10 µg/mL concentration of heparin showed the best antibacterial activity against E. coli. The swelling was considerably increased up to 1500% within 1 h. Alamar Blue assay revealed no cytotoxic effect on NIH3T3. Heparin showed good anti-microbial properties and inhibited the growth of E. coli in zones with a diameter of 18 mm. The expression analysis suggested that heparin probably exerts its pro-angiogenetic effect through VEGF and cPGE. Conclusions: We report that heparin-loaded alginate dressings are not cytotoxic and offer increased angiogenic and anti-bacterial potential. The angiogenesis is apparently taken through the VEGF pathway.
Development of a Computational Model of the Mechanical Behavior of the L4–L5 Lumbar Spine: Application to Disc Degeneration
Authors: Eremina Galina , Smolin Alexey , Xie Jing , Syrkashev Vladimir
Published: September 2022

Degenerative changes in the lumbar spine significantly reduce the quality of life of people. In order to fully understand the biomechanics of the affected spine, it is crucial to consider the biomechanical alterations caused by degeneration of the intervertebral disc (IVD). Therefore, this study is aimed at the development of a discrete element model of the mechanical behavior of the L4–L5 spinal motion segment, which covers all the degeneration grades from healthy IVD to its severe degeneration, and numerical study of the influence of the IVD degeneration on stress state and biomechanics of the spine. In order to analyze the effects of IVD degeneration on spine biomechanics, we simulated physiological loading conditions using compressive forces. The results of modeling showed that at the initial stages of degenerative changes, an increase in the amplitude and area of maximum compressive stresses in the disc is observed. At the late stages of disc degradation, a decrease in the value of intradiscal pressure and a shift in the maximum compressive stresses in the dorsal direction is observed. Such an influence of the degradation of the geometric and mechanical parameters of the tissues of the disc leads to the effect of bulging, which in turn leads to the formation of an intervertebral hernia.
Effectiveness of Different Final Irrigation Procedures on Enterococcus faecalis Infected Root Canals: An In Vitro Evaluation
Authors: Cîmpean Sanda Ileana , Pop-Ciutrila Ioana-Sofia , Matei Sebastian-Roberto , Colosi Ioana Alina , Costache Carmen , Nicula Gheorghe Zsolt , Badea Iulia Clara , Colceriu Burtea Loredana
Published: September 2022

This study aimed to evaluate the antibacterial effect of three final irrigation protocols and to compare their ability to remove the smear layer and debris from the root canal. Methods: Sixty-three single-rooted human teeth were inoculated with Enterococcus faecalis for 14 days. The teeth were divided into a positive control group (N = 3) and three treatment groups (N = 20) as follows: final irrigation with saline solution (control group), irrigation with 5.25% NaOCl ultrasonically activated with EndoUltra (EU), standard needle irrigation with Qmix 2in1 (Qx) and irrigation with 5.25% NaOCl activated using SiroLaser Blue (SB). The bacterial load was evaluated by analyzing the colony-forming units (CFU/mL). Selected specimens were split longitudinally and examined using scanning electron microscopy in order to determine the presence of a smear layer and debris. Statistical analyses were performed using one-way ANOVA and the Kruskal–Wallis rank-sum test. Results: Activation of NaOCl with EndoUltra or SiroLaser Blue was superior at reducing intracanal bacteria relative to standard needle irrigation with Qmix 2in1 solution (p < 0.05). Even though SiroLaser Blue showed the best results for removing the smear layer and debris, no significant differences were detected between the groups (p > 0.05). Conclusions: Final irrigation with 5.25% NaOCl ultrasonically activated using EndoUltra or SiroLaser Blue demonstrated a higher efficacy in bacterial reduction than standard needle irrigation with Qmix 2in1.
Wideband Microwave Photonic Circulator Using Two Asymmetric Partial-Height Triangle Ferrites
Authors: Wang Yong , Xu Biaogang , He Wenlong , Ian Hou
Published: September 2022

Broadband 5G communication requires the operation of nonreciprocal devices in the Ku band. A wideband photonic crystal circulator is implemented by introducing two partial-height triangular Ni-Zn ferrites into the Al2O3 ceramic rod-arrays. The asymmetric sizes of the two equilateral triangles paired with self-matching effectively extend the bandwidth of the circulator eight times over that of the symmetric scheme. Numerical simulations demonstrate that the photonic crystal circulator can obtain a bandwidth of 1.00 GHz with an isolation 25.75 dB and an insertion loss 0.381 dB through optimized matched triangle size ratio, suitable for applications in future communication systems.
Effect of Laser Quenching-Shock Peening Strengthening on the Microstructure and Mechanical Properties of Cr12MoV Steel
Authors: Feng Aixin , Zhao Jian , Lin Jinhao , Pan Xiaoming , Feng Huibin , Wang Changyu , Lu Zhengyuan
Published: September 2022

The automobile covering parts mold is a key piece of equipment in the automobile industry, and its drawbead is the core element that affects the life of the mold and the quality of the parts made. Due to the complex structure of the mold cavity for covering parts, there exist differences between material flow characteristics, load conditions, stress strain, failure forms and so on in the surface of different parts of its drawbead and the different directions of the same part of the drawbead, thus putting forward new requirements for material strengthening. For the differentiated lose efficacy forms of the dangerous end faces of the tension bars, this study carried out research into the effect of laser quenching–shock peening strengthening (LQ-LSP) on the organization, plastic deformation resistance and wear resistance of Cr12MoV steel. It was shown that the microhardness (722.30 HV) and residual stress (−383.84 MPa) of the specimens were further enhanced after laser quenching–shock peening composite strengthening. The residual austenite content of the specimen was reduced to 0.8%, and the eutectic carbide distribution morphology was improved. After three rounds of laser composite peening, the specimens had the smallest displacement of the nanoindentation load–depth curve, which exhibited the greatest nanohardness (20.0 Pa) and modulus of elasticity (565.25 Pa), while reducing the coefficient of friction (0.61) and surface roughness (0.152 Ra). The smooth and flat surface of the specimen with shallow and narrow plow grooves improved the resistance of Cr12MoV steel to plastic deformation and wear.
Inverse Design of Valley-Like Edge States of Sound Degenerated Away from the High-Symmetry Points in a Square Lattice
Authors: Yang Jishi , Liu Yaolu , Sun Dongyang , Hu Ning , Ning Huiming
Published: September 2022

Robust edge states of periodic crystals with Dirac points fixed at the corners or centers of the Brillouin zones have drawn extensive attention. Recently, researchers have observed a special edge state associated with Dirac cones degenerated at the high symmetric boundaries of the first irreducible Brillouin zone. These nodal points, characterized by vortex structures in the momentum space, are attributed to the unavailable band crossing protected by mirror symmetry. By breaking the time reversal symmetry with intuitive rotations, valley-like states can be observed in a pair of inequivalent insulators. In this paper, an improved direct inverse design method is first applied to realize the valley-like states. Compared with the conventional strategy, the preparation of transition structures with degeneracy points is skipped. By introducing the quantitative gauge of mode inversion error, insulator pairs are directly obtained without manually tuning the structure with Dirac cone features.
Nano Minerals Applications in Pollutants Removal: A New Open Special Issue in Materials
Authors: Chang Po-Hsiang , Mukhopadhyay Raj
Published: September 2022

‘Nano Minerals Applications in Pollutants Removal: A New Open Special Issue in Materials’, aims to publish high-quality research and review articles on the basic and applied science of clay mineralogy and make great contributions to the understanding of applied mineralogy in removing pollutants from aqueous and soil environments [...]
Chemically Induced Compatible Interface in Pyrolyzed Bacterial Cellulose/Graphene Sandwich for Electrochemical Energy Storage
Authors: Wang Xiangjun , Xiao Zhichang , Zhang Xinghao , Kong Debin , Wang Bin , Wu Peng , Song Yan , Zhi Linjie
Published: September 2022

Herein, a three-step approach toward a multi-layered porous PBC/graphene sandwich has been developed, in which the chemical bonding interactions have been successfully enhanced via esterification between the layers of pyrolyzed bacterial cellulose (PBC) and graphene. Such a chemically induced compatible interface has been demonstrated to contribute significantly to the mass transfer efficiency when the PBC/graphene sandwich is deployed as electrode material for both supercapacitors and lithium–sulfur batteries. The high specific capacitance of the supercapacitors has been increased by three times, to 393 F g−1 at 0.1 A g−1. A high initial discharge specific capacity (~1100 mAhg−1) and high coulombic efficiency (99% after 300 cycles) of the rPG/S-based lithium–sulfur batteries have been achieved.
The Effect of Drawing in Conventional and Hydrodynamic Dies on Structure and Corrosion Resistance of Hot-Dip Galvanized Zinc Coatings on Medium-Carbon Steel Wire
Authors: Suliga Maciej , Wartacz Radosław , Hawryluk Marek , Kostrzewa Joanna
Published: September 2022

The paper presents the impact of the drawing method on the microstructure and corrosion resistance of galvanized steel wires. The microstructural tests confirmed that, in the drawing speed range v = 5–20 m/s, the use of hydrodynamic dies creates more favorable conditions for the deformation of the soft zinc coating on the hard steel core. The increase in friction at the wire/die interface in the conventional method, as compared to the hydrodynamic method, contributed to the decrease in coating thickness and the increase in the diffusion layer, and the higher the drawing speed, the greater the differences between the analyzed drawing methods. In the conventional method, while drawing at high speeds v = 20 m/s, there was a two-way diffusion and complete remodeling of the ζ phase in δ1. In the hydrodynamic method, at the speed of 20 m/s, in the analyzed micro-areas, places showing the presence of the ζ phase, partially dispersed in the layer with pure zinc, were observed. A corrosion tests comparison between conventionally and hydrodynamically drawn wires showed an improved behavior of the latter. The greater mass in the surface layer of pure zinc, a substrate for the corrosion product in hydrodynamically drawn wires, reacted, creating insulation from the white corrosion produced. The compressive stresses in the hydrodynamic dies caused by the high pressure of the lubricant on the circumference of the wire closed the microcracks on its surface, which additionally sealed the zinc coating.
On the Electronic Structure of 2H-MoS2: Correlating DFT Calculations and In-Situ Mechanical Bending on TEM
Authors: Ramos Manuel , López-Galán Oscar A. , Polanco Javier , José-Yacamán Miguel
Published: September 2022

We present a systematic density functional theory study to determine the electronic structure of bending 2H-MoS2 layers up to 75° using information from in-situ nanoindentation TEM observations. The results from HOMO/LUMO and density of states plots indicate a metallic transition from the typical semiconducting phase, near Fermi energy level (EF) as a function of bending, which can mainly occur due to bending curvatures inducing a stretching and contracting of sulfur-sulfur chemical bonds located mostly over basal (001)-plane; furthermore, molybdenum ions play a major role in such transitions due to reallocation of their metallic d-character orbitals and the creation of “free electrons”, possibly having an overlap between Mo-dx2-y2 and Modz2 orbitals. This research on the metallic transition of 2H-MoS2 allows us to understand the high catalytic activity for MoS2 nanostructures as extensively reported in the literature.
Studies of Simultaneous Friction and Corrosive Processes in the Presence of Abrasive Particles
Authors: Tyczewski Przemyslaw , Nadolny Karol , Zwierzycki Wieslaw , Ulbrich Dariusz
Published: September 2022

Providing high-quality machinery and equipment in technical terms is an activity aimed primarily at ensuring the high reliability of nodes. Reliability of machinery and equipment is mainly characterized by resistance to destructive processes. Mutual displacement of parts causes destructive friction phenomena, the intensity of which can be intensified by the interaction of specific technological environments. The article presents the results of research on ring-on-ring samples made of C45 steel in the non-heat-treated state, which were subjected to mechanical, corrosive, and abrasive wear and various combinations of them. The main purpose of the study was to determine the wear that results from the action of destructive friction and corrosive processes with the presence of abrasive material in the tribological node. The results supplement the knowledge of material wear under the simultaneous action of several destructive factors. Based on the study, it was noticed that the sum component of mechanical–abrasive–corrosive interactions is about 40–50% of the total wear. Mass loss resulting from simultaneous mechanical and abrasive interactions is equal about one-third of the total wear. In addition, it was observed that the effects of the interactions of friction (mechanical), corrosive and abrasive excitations are synergistic in nature, which lead to increases in the total wear of the tested samples made of steel. The results of the research are of practical importance and allow for wear-optimal selection of material in the friction node of modern machinery and equipment.
Electric Discharge Machining on Stainless Steel Using a Blend of Copper and Fly Ash as the Electrode Material
Authors: Balamurugan Ponnambalam , Uthayakumar Marimuthu , Pethuraj Manickaraj , Mierzwiński Dariusz , Korniejenko Kinga , Majid Mohd Shukry Abdul
Published: September 2022

In the current work, several composites made with fly ash reinforcements are used to conduct electrical discharge machining (EDM) on stainless steel that is commercially accessible. Four composites were prepared with 2.5 to 10% reinforcement of fly ash with steps of 2.5%, copper is used as the matrix material. The specimens were created using the powder metallurgy method, which involved compaction pressures of 450 MPa and 900 °C for 90 min of sintering. The prepared composites are used as the electrode tool for EDM. EDM studies were carried out at two different current amplitudes (5A and 15A) by maintaining the Pulse on time (100 µs), Pulse off time (50 µs), and the depth of machining as 2 mm. The findings show that the addition of more fly ash to the copper matrix increased the material removal rate when cutting the SS304 plate and had a negative impact on the tool. The composite loses its ability to transfer heat during machining as the level of fly ash increases, raising the temperature in the copper matrix and causing the copper to melt more quickly at the electrode interface during machining, leading to increased electrode wear. While tool life was reduced because of the increase in current amplitude, machinability was enhanced.
Study of Carrier Mobilities in 4H-SiC MOSFETS Using Hall Analysis
Authors: Das Suman , Zheng Yongju , Ahyi Ayayi , Kuroda Marcelo A. , Dhar Sarit
Published: September 2022

The channel conduction in 4H-SiC metal–oxide–semiconductor field effect transistors (MOSFETs) are highly impacted by charge trapping and scattering at the interface. Even though nitridation reduces the interface trap density, scattering still plays a crucial role in increasing the channel resistance in these transistors. In this work, the dominant scattering mechanisms are distinguished for inversion layer electrons and holes using temperature and body-bias-dependent Hall measurements on nitrided lateral 4H-SiC MOSFETs. The effect of the transverse electric field (Eeff) on carrier mobility is analyzed under strong inversion condition where surface roughness scattering becomes prevalent. Power law dependencies of the electron and hole Hall mobility for surface roughness scattering are determined to be Eeff−1.8 and Eeff−2.4, respectively, analogous to those of silicon MOSFETs. Moreover, for n-channel MOSFETs, the effect of phonon scattering is observed at zero body bias, whereas in p-channel MOSFETs, it is observed only under negative body biases. Along with the identification of regimes governed by different scattering mechanisms, these results highlight the importance of the selection of substrate doping and of Eeff in controlling the value of channel mobility in 4H-SiC MOSFETs.
Heat Loss Analysis of a 2D Pump’s Transmission
Authors: Chang Liang , Li Zhiwei , Li Sheng , Jia Wenang , Ruan Jian
Published: September 2022

Highly enhanced pump power density inevitably results in a profound rise in pump temperature, which seriously influences both power loss and service performance. Heat loss analysis is an important part of analyzing the mechanical and cooling efficiency of a 2D piston pump. This paper focuses on heat loss analysis of this pump’s transmission. Firstly, theoretical and experimental studies are carried out on the thermal–hydraulic model to investigate the heat loss of the pump’s transmission. A pump test rig is developed and thermal experiments are conducted, from 1000 rpm to 6000 rpm. Furthermore, its transient thermal simulation model is implemented with Ansys software to capture the pump’s thermal status. The test convective heat transfer coefficients and temperature data are set in the model, and the simulation results are mutually validated with the experimental ones. Finally, the transmission’s heat loss is compared with its reference churning loss formula. The distribution of the transient heat loss is 49.66% into the end cap, 27.74% into the cylinder head, 13.30% into the inner cylinder, and 9.30% into the oil. The heat loss simulation results agree with the churning loss below 4000 rpm; therefore, the transmission thermal model is accurate and efficient.
Ontology-Driven Guidelines for Architecting Digital Twins in Factory Automation Applications
Authors: Mohammed Wael M. , Haber Rodolfo E. , Martinez Lastra Jose L.
Published: September 2022

The rapid emerging technologies in various fields permitted the creation of simulation tools. These tools are designed to replicate physical systems in order to provide faster, cheaper and more detailed illustrative analysis of the physical system. In this regard, the concept of digital twins has been introduced to generally define these simulation tools. In fact, and according to the creator of the digital twin term Micheal Grieves, a digital twin is defined as a physical system, a digital replica of the physical system and information flow between the former parts. This definition is simple and generic for describing digital twins and yet, holistic. This broad definition creates a challenge for developers who target the development of such applications. Therefore, this paper presents a paradigm for architecting digital twins for manufacturing processes. The approach is inspired by the definitions of the ISA95 standard and the onion concept of computer applications to create multi-layer and multi-level concepts. Furthermore, and to satisfy the different required features by industries, the approach considers a multi-perspective concept that allows the separation of the digital twin views based on functionality. This paradigm aims at providing a modular, scalable, reusable, interoperable and composable approach for developing digital twins. Then, an implementation of the approach has been introduced using an ontology-based system and the IEC61499 standard. This implementation has been demonstrated on a discrete manufacturing assembly line.
State of the Art Review of Active and Passive Knee Orthoses
Authors: Barrera Sánchez Agustín , Blanco Ortega Andrés , Martínez Rayón Eladio , Gómez Becerra Fabio Abel , Abúndez Pliego Arturo , Campos Amezcua Rafael , Guzmán Valdivia César Humberto
Published: September 2022

The use of specialized devices, such as orthopedic devices, has become indispensable in the lives of people with disabilities since ancient times. The primary purpose of such devices is to perform activities and solve problems that afflict their bearers in any extremity of their body. One of the most recurrent problems occurs in the lower extremities regarding mobility and autonomy. In addition, the use of orthopedic devices is considered a tool to lighten the repetitive and heavy rehabilitation work of physiotherapists while improving the patient’s recovery efficiency. A significant challenge is that a great variety of these devices are similar in their design and manufacture, complicating their application in rehabilitation processes. For these reasons, this article aims to provide an overview of the features and considerations made in the architecture of orthosis designs, emphasizing lower extremity orthoses for the case of knee joint analysis. A literature review of active and passive knee orthoses manufactured from the 1970s to the present was carried out, considering aspects such as manufacturing materials, mechanical systems, types of actuators, and control strategies. This review shows that the designs and development of orthoses have been abundant in these devices for lower limbs. Based on the literature collected, we have studied the main robotic devices focusing on the characteristics of design, manufacturing, and control systems to assist in human locomotion and support in rehabilitation processes.
An Attention and Wavelet Based Spatial-Temporal Graph Neural Network for Traffic Flow and Speed Prediction
Authors: Zhao Shihao , Xing Shuli , Mao Guojun
Published: September 2022

Traffic flow prediction is essential to the intelligent transportation system (ITS). However, due to the complex spatial-temporal dependence of traffic flow data, it is insufficient in the extraction of local and global spatial-temporal correlations for the previous process on road network and traffic flow modeling. This paper proposes an attention and wavelet-based spatial-temporal graph neural network for traffic flow and speed prediction (STAGWNN). It integrated attention and graph wavelet neural networks to capture local and global spatial information. Meanwhile, we stacked a gated temporal convolutional network (gated TCN) with a temporal attention mechanism to extract the time series information. The experiment was carried out on real public transportation datasets: PEMS-BAY and PEMSD7(M). The comparison results showed that our proposed model outperformed baseline networks on these datasets, which indicated that STAGWNN could better capture the spatial-temporal correlation information.
Comparative Analysis of a Cone, Wedge, and Plate Packed with Microbes in Non-Fourier Heat Flux
Authors: Santhosh Halavudara Basavarajappa , Upadhya Mamatha Sadananda , Ahammad N. Ameer , Raju Chakravarthula Siva Krishnam , Shah Nehad Ali , Weera Wajaree
Published: September 2022

In this study, we investigated a radiative chemically reactive Casson fluid above a cone, plate, and wedge with gyrotactic microorganisms subjected to the Cattaneo–Christov heat flux model. Newton’s method and the Runge–Kutta methods were employed to solve the physical problem, and a graphical representation of the numerous impacts of non-dimensional parameters on temperature, velocity, and concentration was created. In addition, we also compared recently published solutions with our current solution, which showed good agreement. From this investigation, we concluded that the motile organisms’ momentum, temperature, and concentration density were non-uniform in nature. Here, for engineering importance, we also present the mass transfer and thermal transfer rate over the cone, wedge, and plate cases in a tabular form. We concluded that the mass and heat transfer rate was larger over the cone when compared to the same case over a plate or wedge. The results also highlighted that the local Nusselt and Sherwood numbers and the mass density of the microorganisms depreciated as the Casson fluid parameter decreased. In summary, we concluded that the gyrotactic microorganisms played a role in enhancing the local Sherwood number.
Joint Semantic Intelligent Detection of Vehicle Color under Rainy Conditions
Authors: Hu Mingdi , Wu Yi , Fan Jiulun , Jing Bingyi
Published: September 2022

Color is an important feature of vehicles, and it plays a key role in intelligent traffic management and criminal investigation. Existing algorithms for vehicle color recognition are typically trained on data under good weather conditions and have poor robustness for outdoor visual tasks. Fine vehicle color recognition under rainy conditions is still a challenging problem. In this paper, an algorithm for jointly deraining and recognizing vehicle color, (JADAR), is proposed, where three layers of UNet are embedded into RetinaNet-50 to obtain joint semantic fusion information. More precisely, the UNet subnet is used for deraining, and the feature maps of the recovered clean image and the extracted feature maps of the input image are cascaded into the Feature Pyramid Net (FPN) module to achieve joint semantic learning. The joint feature maps are then fed into the class and box subnets to classify and locate objects. The RainVehicleColor-24 dataset is used to train the JADAR for vehicle color recognition under rainy conditions, and extensive experiments are conducted. Since the deraining and detecting modules share the feature extraction layers, our algorithm maintains the test time of RetinaNet-50 while improving its robustness. Testing on self-built and public real datasets, the mean average precision (mAP) of vehicle color recognition reaches 72.07%, which beats both sate-of-the-art algorithms for vehicle color recognition and popular target detection algorithms.
Performance Evaluation of Query Plan Recommendation with Apache Hadoop and Apache Spark
Authors: Azhir Elham , Hosseinzadeh Mehdi , Khan Faheem , Mosavi Amir
Published: September 2022

Access plan recommendation is a query optimization approach that executes new queries using prior created query execution plans (QEPs). The query optimizer divides the query space into clusters in the mentioned method. However, traditional clustering algorithms take a significant amount of execution time for clustering such large datasets. The MapReduce distributed computing model provides efficient solutions for storing and processing vast quantities of data. Apache Spark and Apache Hadoop frameworks are used in the present investigation to cluster different sizes of query datasets in the MapReduce-based access plan recommendation method. The performance evaluation is performed based on execution time. The results of the experiments demonstrated the effectiveness of parallel query clustering in achieving high scalability. Furthermore, Apache Spark achieved better performance than Apache Hadoop, reaching an average speedup of 2x.
Applications of a Group Theoretical Method on Biomagnetic Fluid Flow and Heat Transfer for Different Shapes of Fe3O4 Magnetic Particles under the Influence of Thermal Radiation and a Magnetic Dipole over a Cylinder
Authors: Alam Jahangir , Murtaza Ghulam , Petropoulou Eugenia N. , Tzirtzilakis Efstratios Em. , Ferdows Mohammad
Published: September 2022

The flow and heat characteristics of an unsteady, laminar biomagnetic fluid, namely blood containing Fe3O4 magnetic particles, under the influence of thermal radiation and a magnetic dipole over a cylinder with controlled boundary conditions using a group theory method are investigated in the present study. The mathematical formulation of the problem is constructed with the aid of biomagnetic fluid dynamics (BFD) which combines principles of ferrohydrodynamics (FHD) and magnetohydrodynamics (MHD). It is assumed that blood exhibits polarization as well as electrical conductivity. Additionally, the shape of the magnetic particles, namely cylindrical and spherical, is also considered. Moreover, in this model, a group theoretical transformation, namely a two-parameter group technique, is applied. By applying this group transformation, the governing system of partial differential equations (PDEs) along with applicable boundary conditions are reduced to one independent variable and, consequently, converted into a system of ordinary differential equations (ODEs) with suitable boundary conditions. An efficient numerical technique is applied to solve the resultant ODEs and this technique is based on three essential features, namely (i) a common finite differences method with central differencing, (ii) tridiagonal matrix manipulation and (iii) an iterative procedure. The flow and heat characteristics of blood-Fe3O4 are found to be dependent on some physical parameters such as the particle volume fraction, the ferromagnetic interaction parameter, the magnetic field parameter, and the thermal radiation parameter. An ample parametric study is accomplished to narrate the influences of such physical parameters on velocity, temperature distributions as well as the coefficient of skin friction and rate of heat transfer. From the numerical results, it is deduced that the fluid velocity is enhanced for the ferromagnetic number and the temperature profile is decreased as the ferromagnetic number is gradually increased. It is also obtained that for the cylindrical shape of magnetic particles, the fluid temperature is more enhanced than that of the spherical shape. Both the skin friction coefficient and the local Nusselt number are increased for increasing values of the ferromagnetic interaction parameter, where the heat transfer rate of blood-Fe3O4 is significantly increased by approximately 33.2% compared to that of pure blood, whereas the coefficient of skin friction is reduced by approximately 6.82%.