bluuebunny/crossref_metadata_2025 huggingface dataset:
Semantic Recognition of Ship Motion Patterns Entering and Leaving Port Based on Topic Model
Authors: Li Gaocai , Liu Mingzheng , Zhang Xinyu , Wang Chengbo , Lai Kee-hung , Qian Weihuachao
Published: December 2022

Recognition and understanding of ship motion patterns have excellent application value for ship navigation and maritime supervision, i.e., route planning and maritime risk assessment. This paper proposes a semantic recognition method for ship motion patterns entering and leavingport based on a probabilistic topic model. The method enables the discovery of ship motion patterns from a large amount of trajectory data in an unsupervised manner and makes the results more interpretable. The method includes three modules: trajectory preprocessing, semantic process, and knowledge discovery. Firstly, based on the activity types and characteristics of ships in the harbor waters, we propose a multi-criteria ship motion state recognition and voyage division algorithm (McSMSRVD), and ship trajectory is divided into three sub-trajectories: hoteling, maneuvering, and normal-speed sailing. Secondly, considering the influence of port traffic rules on ship motion, the semantic transformation and enrichment of port traffic rules and ship location, course, and speed are combined to construct the trajectory text document. Ship motion patterns hidden in the trajectory document set are recognized using the Latent Dirichlet allocation (LDA) topic model. Meanwhile, topic coherence and topic correlation metrics are introduced to optimize the number of topics. Thirdly, a visualization platform based on ArcGIS and Electronic Navigational Charts (ENCs) is designed to analyze the knowledge of ship motion patterns. Finally, the Tianjin port in northern China is used as the experimental object, and the results show that the method is able to identify 17 representative inbound and outbound motion patterns from AIS data and discover the ship motion details in each pattern.
Submarine Manoeuvrability Design: Traditional Cross-Plane vs. x-Plane Configurations in Intact and Degraded Conditions
Authors: Piaggio Benedetto , Vernengo Giuliano , Ferrando Marco , Mazzarello Giorgio , Viviani Michele
Published: December 2022

Submarines’ manoeuvrability both in intact and degraded operating conditions is the main design concern starting at the very early stages of design. This increased complexity of the design process compared to a surface vehicle can only be handled by using dynamics numerical simulations on both the vertical and horizontal manoeuvring planes. To this aim, a 6-DoF method is presented, validated, and applied to study the manoeuvring characteristics of several vessels. The analysis has been conducted considering two standpoints, i.e., to verify the design handling capabilities of the vehicles at low and high speeds and to study the off-design residual abilities in the eventual case of emergency operations with jammed/lost-control surfaces. The influence of different design features, such as, e.g., the stern plane “+” and “x” configurations, fairway size and positioning, hull dimensional ratios and restoring capabilities have been analysed in terms of impact on turning ability, course and depth changing abilities, and vertical/horizontal course stability, including the vertical damping ratio and critical velocity.
Numerical Investigations on Scour and Flow around Two Crossing Pipelines on a Sandy Seabed
Authors: Zhang Fan , Zang Zhipeng , Zhao Ming , Zhang Jinfeng , Xie Botao , Zou Xing
Published: December 2022

When a pipeline is laid on the seabed, local scour often occurs below it due to sea currents. In practical engineering, there are some cases that two pipelines laid on the seabed need to cross with each other. The complex flow structures around two crossing pipelines make the scour characteristics different from that of an isolated single pipeline. In this study, scour below two crossing pipelines was simulated numerically using the CFD software Flow-3D. The study is focused on the effect of the intersecting angle on the equilibrium depth and time scale of scour below the crossing position. Five intersecting angles, i.e., α = 0°, 15°, 30°, 45° and 90°, are considered, where α = 0° and 90° represent two pipelines parallel and perpendicular to each other, respectively. The results show that the equilibrium depth and the time scale of scour below the two crossing pipelines are greater than those of an isolated single pipeline. The equilibrium depth and time scale of scour have the largest values at α = 0° and decrease with the increase of the intersecting angle. Finally, the flow structures around the crossing pipelines are presented to explain the scour process.
Geological Oceanography: Towards a Conceptual Framework
Authors: Kontakiotis George , Antonarakou Assimina , Ruban Dmitry A.
Published: December 2022

Research into modern oceans, seas, and their coastal zones, as well as marine ecosystems, provides valuable information for deciphering the geological dynamics [...]
Learning-Based Nonlinear Model Predictive Controller for Hydraulic Cylinder Control of Ship Steering System
Authors: Tang Xiaolong , Wu Changjie , Xu Xiaoyan
Published: December 2022

The steering mechanism of ship steering gear is generally driven by a hydraulic system. The precise control of the hydraulic cylinder in the steering mechanism can be achieved by the target rudder angle. However, hydraulic systems are often described as nonlinear systems with uncertainties. Since the system parameters are uncertain and system performances are influenced by disturbances and noises, the robustness cannot be satisfied by approximating the nonlinear theory by a linear theory. In this paper, a learning-based model predictive controller (LB-MPC) is designed for the position control of an electro-hydraulic cylinder system. In order to reduce the influence of uncertainty of the hydraulic system caused by the model mismatch, the Gaussian process (GP) is adopted, and also the real-time input and output data are used to improve the model. A comparative simulation of GP-MPC and MPC is performed assuming that the interference and uncertainty terms are bounded. Consequently, the proposed control strategy can effectively improve the piston position quickly and precisely with multiple constraint conditions.
A Novel Gammapartitivirus That Causes Changes in Fungal Development and Multi-Stress Tolerance to Important Medicinal Fungus Cordyceps chanhua
Authors: Zhu Qiuyan , Shi Najie , Wang Ping , Zhang Yuxiang , Peng Fan , Yang Guogen , Huang Bo
Published: December 2022

Cicada flower, scientifically named Cordyceps chanhua, is an important and well-known Chinese cordycipitoid medicinal mushroom. Although most mycoviruses seem to induce latent infections, some mycoviruses cause host effects. However, the effects of mycovirus on the fungal development and stress tolerance of C. chanhua remain unknown. In this study, we report a novel mycovirus designated Cordyceps chanhua partitivirus 1 (CchPV1) from C. chanhua isolate RCEF5997. The CchPV1 genome comprises dsRNA 1 and dsRNA 2, 1784 and 1563 bp in length, respectively. Phylogenetic analysis using the aa sequences of RdRp revealed that CchPV1 grouped with members of the genus Gammapartitivirus in the family Partitiviridae. We further co-cultivated on PDA donor strain RCEF5997 and recipient C. chanhua strain RCEF5833 (Vf) for 7 days, and we successfully obtained an isogenic line of strain RCEF5833 with CchPV1 (Vi) through single-spore isolation, along with ISSR marker and dsRNA extraction. The biological comparison revealed that CchPV1 infection slows the growth rate of the host, but increases the conidiation and formation of fruiting bodies of the host. Furthermore, the assessment of fungal tolerance demonstrated that CchPV1 weakens the multi-stress tolerance of the host. Thus, CchPV1 infection cause changes in fungal development and multi-stress tolerance of the host C. chanhua. The findings of this study elucidate the effects of gammapartitivirus on host entomogenous fungi and provide a novel strategy for producing high-quality fruiting bodies of C. chanhua.
Natural Product Citronellal can Significantly Disturb Chitin Synthesis and Cell Wall Integrity in Magnaporthe oryzae
Authors: Zhou Ai-Ai , Li Rong-Yu , Mo Fei-Xu , Ding Yi , Li Ruo-Tong , Guo Xue , Hu Ke , Li Ming
Published: December 2022

Background: Natural products are often favored in the study of crop pests and diseases. Previous studies have shown that citronellal has a strong inhibition effect on Magnaporthe oryzae. The objective of this study was to clarify its mechanism of action against M. oryzae. Results: Firstly, the biological activity of citronellal against M. oryzae was determined by direct and indirect methods, and the results show that citronellal had a strong inhibition effect on M. oryzae with EC50 values of 134.00 mg/L and 70.48 μL/L air, respectively. Additionally, a preliminary study on its mechanism of action was studied. After citronellal treatment, electron microscopy revealed that the mycelium became thin and broken; scanning electron microscopy revealed that the mycelium was wrinkled and distorted; and transmission electron microscopy revealed that the mycelium cell wall was invaginated, the mass wall of mycelium was separated, and the organelles were blurred. The mycelium was further stained with CFW, and the nodes were blurred, while the mycelium was almost non-fluorescent after PI staining, and there was no significant difference in the relative conductivity of mycelium. In addition, chitinase was significantly enhanced, and the expression of chitin synthesis-related genes was 17.47-fold upregulated. Finally, we found that the efficacy of citronellal against the rice blast was as high as 82.14% according to indoor efficacy tests. Conclusion: These results indicate that citronellal can affect the synthesis of chitin in M. oryzae and damage its cell wall, thereby inhibiting the growth of mycelium and effectively protecting rice from rice blasts.
Inhibition of Dopamine Activity and Response of Rhipicephalus microplus Challenged with Metarhizium anisopliae
Authors: Bório Victória Silvestre , Corrêa Thaís Almeida , Fiorotti Jéssica , Mesquita Emily , Meirelles Laura Nóbrega , Camargo Mariana Guedes , Bittencourt Vânia Rita Elias Pinheiro , Golo Patrícia Silva
Published: December 2022

Dopamine modulates ticks and insect hemocytes and links these arthropods’ nervous and immune systems. For the first time, the present study analyzed the effect of a dopamine receptor antagonist on the survival, biological parameters, phagocytic index, and dopamine detection in the hemocytes of ticks challenged by Metarhizium anisopliae. The survival and egg production index of Rhipicephalus microplus were negatively impacted when ticks were inoculated with the antagonist and fungus. Five days after the treatment, the survival of ticks treated only with fungus was 2.2 times higher than ticks treated with the antagonist (highest concentration) and fungus. A reduction in the phagocytic index of hemocytes of 68.4% was observed in the group inoculated with the highest concentration of the antagonist and fungus compared to ticks treated only with fungus. No changes were detected in the R. microplus levels of intrahemocytic dopamine or hemocytic quantification. Our results support the hypothesis that dopamine is crucial for tick immune defense, changing the phagocytic capacity of hemocytes and the susceptibility of ticks to entomopathogenic fungi.
The SsAtg1 Activating Autophagy Is Required for Sclerotia Formation and Pathogenicity in Sclerotinia sclerotiorum
Authors: Jiao Wenli , Yu Huilin , Chen Xueting , Xiao Kunqin , Jia Dongmei , Wang Fengting , Zhang Yanhua , Pan Hongyu
Published: December 2022

Sclerotinia sclerotiorum is a necrotrophic phytopathogenic fungus that produces sclerotia. Sclerotia are essential components of the survival and disease cycle of this devastating pathogen. In this study, we analyzed comparative transcriptomics of hyphae and sclerotia. A total of 1959 differentially expressed genes, 919 down-regulated and 1040 up-regulated, were identified. Transcriptomes data provide the possibility to precisely comprehend the sclerotia development. We further analyzed the differentially expressed genes (DEGs) in sclerotia to explore the molecular mechanism of sclerotia development, which include ribosome biogenesis and translation, melanin biosynthesis, autophagy and reactivate oxygen metabolism. Among these, the autophagy-related gene SsAtg1 was up-regulated in sclerotia. Atg1 homologs play critical roles in autophagy, a ubiquitous and evolutionarily highly conserved cellular mechanism for turnover of intracellular materials in eukaryotes. Therefore, we investigated the function of SsAtg1 to explore the function of the autophagy pathway in S. sclerotiorum. Deficiency of SsAtg1 inhibited autophagosome accumulation in the vacuoles of nitrogen-starved cells. Notably, ΔSsAtg1 was unable to form sclerotia and displayed defects in vegetative growth under conditions of nutrient restriction. Furthermore, the development and penetration of the compound appressoria in ΔSsAtg1 was abnormal. Pathogenicity analysis showed that SsAtg1 was required for full virulence of S. sclerotiorum. Taken together, these results indicate that SsAtg1 is a core autophagy-related gene that has vital functions in nutrient utilization, sclerotia development and pathogenicity in S. sclerotiorum.
Lomasomes and Other Fungal Plasma Membrane Macroinvaginations Have a Tubular and Lamellar Genesis
Authors: Mazheika Igor S. , Psurtseva Nadezhda V. , Kamzolkina Olga V.
Published: December 2022

The plasma membrane of filamentous fungi forms large-sized invaginations, which are either tubes or parietal vesicles. Vesicular macroinvaginations at the ultrastructural level correspond to classical lomasomes. There is an assumption that vesicular macroinvaginations/lomasomes may be involved in macrovesicular endocytosis. The original aim of this study was to test for the presence of macroendocytosis in xylotrophic basidiomycetes using time-lapse and Z-stacks fluorescent microscopic technologies. However, the results were unexpected since most of the membrane structures labeled by the endocytic tracer (FM4-64 analog) are various types of plasma membrane macroinvaginations and not any endomembranes. All of these macroinvaginations have a tubular or lamellar genesis. Moreover, under specific conditions of a microscopic preparation, the diameter of the tubes forming the macroinvaginations increases with the time of the sample observation. In addition, the morphology and successive formation of the macroinvaginations mimic the endocytic pathway; these invaginations can easily be mistaken for endocytic vesicles, endosomes, and vacuole-lysosomes. The paper analyzes the various macroinvagination types, suggests their biological functions, and discusses some features of fungal endocytosis. This study is a next step toward understanding complex fungal physiology and is a presentation of a new intracellular tubular system in wood-decaying fungi.
Newton–Raphson Emulation Network for Highly Efficient Computation of Numerous Implied Volatilities
Authors: Lee Geon , Kim Tae-Kyoung , Kim Hyun-Gyoon , Huh Jeonggyu
Published: December 2022

In finance, implied volatility is an important indicator that reflects the market situation immediately. Many practitioners estimate volatility by using iteration methods, such as the Newton–Raphson (NR) method. However, if numerous implied volatilities must be computed frequently, the iteration methods easily reach the processing speed limit. Therefore, we emulate the NR method as a network by using PyTorch, a well-known deep learning package, and optimize the network further by using TensorRT, a package for optimizing deep learning models. Comparing the optimized emulation method with the benchmarks, implemented in two popular Python packages, we demonstrate that the emulation network is up to 1000 times faster than the benchmark functions.
Deployment of Solar Energy at the Expense of Conservation Sensitive Areas Precludes Its Classification as an Environmentally Sustainable Activity
Authors: Valera Francisco , Bolonio Luis , La Calle Abel , Moreno Eulalia
Published: December 2022

Solar energy (SE) is essential for the decarbonization of our economy and for energetic transition. Solar energy can be a sustainable economic activity, as long as a balance is struck between the benefits it brings to climate change mitigation and the damage it can cause to biodiversity and ecosystems. Here, we study this balance in an area with high biodiversity under pressure for installation of numerous photovoltaic plants (PPs). Our results show that developers give priority to the cheapest land close to connection points, while other values (e.g., environmental, landscape) are secondary. The regulatory process carried out by the Administration does not ensure the preservation of natural values, as several PPs with a high impact on important conservation areas have been approved. Experts’ allegations provide quality information to the Administration to evaluate and demand changes to the projects presented. Such demands show that companies are willing to relocate plants to land occupied by olive groves. In this way, greater efficiency is achieved in land occupation, as well as shorter evacuation lines, water savings and a smaller environmental impact. Prior strategic territorial planning could have avoided the impact of PPs already built, made the deployment of new PPs compatible with biodiversity conservation, and contributed to improving the management of key resources, such as subway aquifers. The proposed regulatory changes to the environmental assessment procedure (exclusion of renewables and public participation from the procedure) are detrimental, as they will make SE unable to meet the requirements of the Taxonomy Regulation.
Language Contact and Phonological Innovation in the Voiced Prepalatal Obstruents of Judeo-Spanish
Authors: Bradley Travis G. , Lozano Claire Julia
Published: December 2022

This article traces the development of voiced prepalatal obstruents /dʒ⌢/ and /ʒ/ in Judeo-Spanish, the language spoken by the Sephardic Jews since before their expulsion from late-15th century Spain. Using Medieval Spanish as a comparative starting point, we examine diachronic innovations in the phonological status and distribution of affricate /dʒ⌢/ and fricative /ʒ/ in Judeo-Spanish during the diaspora, focusing in particular on the effects of lexical borrowing from Turkish and French in territories of the former Ottoman Empire. In contemporary Sephardic communities that are in contact with non-Sephardic varieties of Mainstream Spanish, some speakers occasionally replace syllable-initial /∫/, /dʒ⌢/, and /ʒ/ in certain Judeo-Spanish words by a voiceless velar /x/ in efforts to accommodate the pronunciation of the corresponding Mainstream Spanish cognate form. We provide a novel analysis of Judeo-Spanish voiced prepalatal obstruents, including their diachronic and synchronic variation under language contact. The analysis combines a constraint-based approach to phonological alternations, as formalized in Optimality Theory, with a usage-based representation of the mental lexicon, as proposed in Exemplar Theory, to account for speaker- and word-specific variability. A hybrid theoretical model provides a more nuanced understanding of the relationship between lexicon and grammar in Judeo-Spanish phonology than is available in previous structuralist descriptions.
Argument Marking and Verbal Agreement in the Speech of Georgian Children
Authors: Makharoblidze Tamar , Damenia Teona , Doborjginidze Nino , Tsintsadze Nino , Tchintcharauli Tinatin , Kalkhitashvili Tamar
Published: December 2022

This paper describes the language acquisition and verb-forming processes related to the issue of argument marking for native-speaker Georgian children from 24 to 42 months of age, who were born and raised in Georgia. Because of the complexity of the Georgian verbal system, it is a challenge to study the acquisition process in this language. We attempted to observe how native-speaker children overcome this complexity during the acquisition process. The study is based on samples of four Georgian-speaking children from the developing corpus of Georgian-speaking children.
Lipid Handling Protein Gene Expression in Colorectal Cancer: CD36 and Targeting miRNAs
Authors: Niculae Andrei Marian , Dobre Maria , Herlea Vlad , Vasilescu Florina , Ceafalan Laura Cristina , Trandafir Bogdan , Milanesi Elena , Hinescu Mihail Eugen
Published: December 2022

The reprogramming of lipid metabolism has been highlighted in colorectal cancer (CRC) studies, suggesting a critical role for the scavenger receptor CD36 and fatty acid synthase (FASN) in this malignancy. In this study, we analyzed the gene expression levels of CD36, FASN, the cell surface glypican 4 (GPC4), and the two transporters SLC27A3 and SLC27A4 in 39 paired tumoral and peritumoral tissues from patients with CRC compared with 18 normal colonic mucosae. Moreover, the levels of seven miRNAs targeting CD36 and most of the analyzed genes were evaluated. We found a significant impairment of the expression of all the analyzed genes except GPC4 as well as the differential expression of miR-16-5p, miR-26b-5p, miR-107, miR-195-5p, and miR-27a-3p in the colonic mucosa of CRC patients. Interestingly, CD36 and miR-27a-3p were downregulated and upregulated, respectively, in tumoral tissues compared to peritumoral and control tissues, with a significant negative correlation in the group of patients developing lymph node metastasis. Our results sustain the relationship between CRC and fatty acid metabolism and emphasize the importance of related miRNAs in developing new therapeutic strategies.
Cutoff Point of Mini-Balance Evaluation Systems Test Scores for Elderly Estimated by Center of Pressure Measurements by Linear Regression and Decision Tree Classification
Authors: Liao Wen-Yen , Chu Yu-Hsiu , Liu Fan-Yu , Chang Kang-Ming , Chou Li-Wei
Published: December 2022

Background: Understanding balance ability and assessing the risk of possible falls are very important for elderly rehabilitation. The Mini-Balanced Evaluation System Test (Mini-BESTest) is an important survey for older adults to evaluate subject balance, but it is not easy to complete due to various limitations of physical activities, including occasional fear of injury. A center of pressure (CoP) signal can be extracted from a force pressure plate with a short recording time, and it is relatively achievable to ask subjects to stand on a force pressure plate in a clinical environment. The goal of this study is to estimate the cutoff score of Mini-BESTest scores from CoP data. Methods: CoP signals from a human balance evaluation database with data from 75 people were used. Time domain, frequency domain, and nonlinear domain parameters of 60 s CoP signals were extracted to classify different cutoff point scores for both linear regression and a decision tree algorithm. Classification performances were evaluated by accuracy and area under a receiver operating characteristic curve. Results: The correlation coefficient between real and estimated Mini-BESTest scores by linear regression is 0.16. Instead of linear regression, binary classification accuracy above or below a cutoff point score was developed to examine the CoP classification performance for Mini-BESTest scores. The decision tree algorithm is superior to regression analysis among scores from 16 to 20. The highest area under the curve is 0.76 at a cutoff point score of 21 for the CoP measurement condition of eyes opened on the foam, and the corresponding classification accuracy is 76.15%. Conclusions: CoP measurement is a potential tool to estimate corresponding balance and fall survey scores for elderly rehabilitation and is useful for clinical users.
Convolvulus arvensis: Antioxidant, Antibacterial, and Antifungal Properties of Chemically Profiled Essential Oils: An Approach against Nosocomial Infections
Authors: Salamatullah Ahmad Mohammad
Published: December 2022

Convolvulus arvensis is a medicinal plant in the family Convolvulaceae, which is used in traditional phytotherapy. The objective of this work was conducted to valorize essential oils of Convolvulus arvensis (EOCA) in terms of chemical composition, antioxidant, and antibacterial properties. To achieve this objective, the chemical composition was performed by the use of GC-SM. Antioxidant power was effectuated by the use of DPPH, FRAP, and TAC assays. Evaluation of the antimicrobial power was conducted against clinically important pathogenic bacteria (E. coli, K. pneumoniae, S. pneumoniae, and S. aureus) and fungi (A. niger, C. albicans, and A. flavus) by the use of disc diffusion and minimum inhibitory concentrations (MICs) assays. The results showed that the yield of recovered EOs from Convolvulus arvensis was 0.34% of the total mass of leaves and mainly was rich in cuprenne (34%), thymol (20%), himachalene (16%), and longifolene (10%). Notably, EOCA exhibited important antioxidant effects, wherein IC50 (DPPH) and EC50 (FRAP) were determined to be 30 µg/mL and 120 µg/mL, respectively, while the total antioxidant power was determined to be 508.0 ± 6.0 µg EAA/mg. An important antibacterial effect was noted for EOCA as an excellent inhibition zone was recorded against all bacterial strains, particularly K. pneumoniae and S. aureus with 14.27 ± 0.42 and 21.35 ± 0.76 mm, respectively. Similarly, MICs of K. pneumoniae and S. aureus were 21.35 ± 0.76 mm and 28.62 ± 1.65 µg/mL, respectively. Noticeably, important antifungal activity was shown by EOCA against all fungal strains wherein the inhibition zone diameters against all fungal species ranged from 19.44 ± 1.10 to 20.41 ± 1.81 mm. Notably, MICs of EOCA against F. oxysporum and C. albicans were 18.65 ± 0.94 and 19.38 ± 0.58 g/mL, respectively. The outcome of the present work showed that EOs from Convolvulus arvensis can be used to conceptualize drugs to manage diseases relative to free radicals and infections.
Potential Effect of DIMBOA (2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one) on Alleviating the Autotoxic Coumarin Stress in Alfalfa (Medicago sativa) Seedlings
Authors: Li Xiaolong , Shi Shangli , Zhang Xiaoyan , Li Changning , Wang Huning , Kang Wenjuan , Yin Guoli
Published: December 2022

The allelopathic theory has garnered considerable attention in the field of agricultural production for its efficient plant protection, rapid crop yield increase, and scientific establishment of the crop rotation system. To study the effects of the main maize allelochemical DIMBOA (2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one) on the growth and development of alfalfa under autotoxic coumarin stress, we treated alfalfa seedlings with DIMBOA under coumarin stress and non-stress conditions in this study. Results show that 0.0342 mM coumarin significantly inhibited alfalfa seed germination percentage(Gp), germination potential(GP), radicle length, germ length, seeding height, and simple viability index (SVI), with decreases of 37.29%, 59.91%, 7.60%, 30.90%, 13.27%, and 45.70%, respectively. An amount of 0.6 mM DIMBOA could promote alfalfa seed Gp, GP, radicle length, germ length, seeding height, dry fresh ratio, and SVI, with increases of 12.38%, 23.91%, 48.69%, 48.65%, 48.68%, 295.12%, and 67.17%, respectively. However, the addition of DIMBOA under conditions of coumarin stress could effectively alleviate coumarin effects on alfalfa seedlings. Coumarin + DIMBOA treatment for 24 h mainly decreased reactive oxygen species (ROSs) and malondialdehyde (MDA) as well as soluble protein and soluble sugar, increasing some antioxidant enzyme activities and antioxidant content to alleviate the oxidative damage of alfalfa caused by coumarin stress. Administration of treatment for 72 h significantly promoted the morphological development of alfalfa seeding roots. Administration of treatment for 96 h significantly enhanced the photosynthetic capacity of alfalfa seedlings. The results of principal component analysis demonstrated that chlorophyll b(Chl b)and net photosynthetic rate(Pn) were the key indicators for coumarin + DIMBOA treatment to promote photosynthesis in alfalfa seedlings. Additionally, root length, mean root diameter, and root volume were the key indicators of root growth and development. Coumarin + DIMBOA treatment primarily increased catalase(CAT), peroxidase (POD), and ascorbate peroxidase (APX) activity and antioxidants(ASA) while reducing MDA and superoxide anion radical(O2•−). This study strongly suggested that DIMBOA can effectively improve the tolerance of alfalfa seedlings to coumarin stress through a combination of effects on root morphology, photosynthesis, and physiological indicators.
Aging and Wound Healing of the Skin: A Review of Clinical and Pathophysiological Hallmarks
Authors: Khalid Kamarul Ariffin , Nawi Ahmad Faris Mohd , Zulkifli Nuraqilah , Barkat Md. Abul , Hadi Hazrina
Published: December 2022

Aging is a universal process that can cause diminished function of organs and various diseases. The most striking consequences of aging can be seen visibly on the skin, which acts as a barrier against various external insults. Aging of the skin consists of intrinsic and extrinsic processes that work in concert and influence each other. Intrinsic aging involves biochemical degenerative processes that gradually takes place with age. Extrinsic aging are biochemical processes driven by external influences that lead to aging. There are significant morphological changes at all levels in aged skin that have a profound effect on the characteristics of the skin. Even though skin is subjected to damage by external insults, it is equipped with a healing capability in order to restore its normal structure and function. However, aging has a significant impact on the skin’s healing function by prolonging the inflammatory phase and increasing the production of reactive oxygen species (ROS). This shifts the healing process towards having more protein degradation, which can lead to chronic wound healing with an abundance of complications.
Performance of Al2O3/TiO2 Hybrid Nano-Cutting Fluid in MQL Turning Operation via RSM Approach
Authors: Arifuddin Ariffin , Redhwan Abd Aziz Mohammad , Azmi Wan Hamzah , Zawawi Nurul Nadia Mohd
Published: December 2022

Cutting fluids can be used to cool workpieces at high cutting speeds and remove chips from cutting zones. The effectiveness of cutting fluids may be improved with the addition of hybrid nanoparticle dispersion. This study evaluates the effectiveness of an Al2O3-TiO2 hybrid as a cutting fluid in turning operations. The Al2O3-TiO2 hybrid nano-cutting fluid was prepared using a one-step method in computer numerical control (CNC) coolant with concentrations of up to 4%. Utilizing air-assisted nano-cutting fluids injected through a minimum quantity lubrication (MQL) setup, the effectiveness of turning cutting performance, cutting temperature (°C), average surface roughness (Ra), and tool wear (%) were evaluated. Then, the response surface method (RSM) was utilized as the design of experiment (DOE) to optimize the turning cutting performance parameters. The combination of 4% hybrid nano-cutting fluid concentration, 0.1 mm/rev feed rate, and 0.55 mm depth of cut yielded the lowest cutting temperature, surface roughness, and tool wear values of 25.3 °C, 0.480 µm, and 0.0104%, respectively. The 4% concentration of Al2O3/TiO2 hybrid nano-cutting fluid inclusion achieved the highest surface roughness reduction that led to better surface finish and the lowest tool-wear reduction led to longer tool life. Therefore, Al2O3/TiO2 hybrid nano-cutting fluids were strongly recommended in turning operations for CNC lathes.
Ultrasound Assisted One-Pot Synthesis of Novel 3-(Aryl)-5-((4-(phenyldiazenyl)phenoxy)methyl)isoxazolines in Water
Authors: El Mahmoudi Ayoub , Karrouchi Khalid , Tachallait Hamza , Bougrin Khalid
Published: December 2022

In this work, we present an efficient one-pot method for the synthesis of three new azo-isoxazoline derivatives (4a–c) from aromatic aldehydes, hydroxylamine hydrochloride and 4-(allyloxy)azobenzene. Thus, the azo-isoxazoline derivatives (4a–c) were synthesized via 1,3-dipolar cycloaddition using sodium dichloroisocyanurate (SDIC) as an eco-friendly and inexpensive oxidizing agent under ultrasound cavitation in water as a green solvent. The desired compounds 4a–c were obtained in high to excellent yields of 75–90%.
The Effect of Rotary-Die Equal-Channel Angular Pressing Process on the Microstructure, the Mechanical and Friction Properties of GW103 Alloy
Authors: Chen Cai , Han Dongsheng , Wang Mingchuan , Cai Ting , Liang Ningning , Beausir Benoit , Liu Huan , Yang Sen
Published: December 2022

In this study, the effect of rotary-die equal-channel angular pressing (RD-ECAP) on the microstructure and texture evolution of GW103 alloy is studied. RD-ECAP processes were carried out for 1, 4 and 12 passes at 450 °C. The mechanical properties and friction behavior of RD-ECAP-processed Mg-10Gd-3Y (wt%) alloy (GW103) are discussed. The results reveal that the size of dynamic recrystallized grains and second-phase particles are significantly refined to about 1.3 μm and 1 μm, respectively. The texture evolution of the processed samples is studied by X-ray diffraction and electron backscattered diffraction techniques. The multiple texture components formed are not observed after the conventional ECAP process. Moreover, different dynamic recrystallization (DRX) mechanisms are systemically analyzed and discussed in view of the texture evolution of ECAP processed samples. The final textures obtained after 12 passes are identified as two types: The C-texture type induced by continuous and discontinuous DRX, and the random texture components induced by reorientation of the initial <101¯0> fiber. Based on the grain refinement, precipitate strengthening and texture weakening mechanisms, a high-performance ternary alloy of Mg-Gd-Y was firstly obtained through 12 passes RD-ECAP processing, with a combination of high yield strength of 312 MPa and a high ductility of 22%. In addition, the friction behaviors are also studied. The multi-pass-processed samples exhibit a relatively lower friction coefficient under a load of 10 N at room temperature.
Microstructural, Corrosion Resistance, and Tribological Properties of Al2O3 Coatings Prepared by Atmospheric Plasma Spraying
Authors: Bejinariu Costică , Paleu Viorel , Stamate Ciprian , Cimpoesu Ramona , Coteată Margareta , Badarau Gheorghe , Axinte Mihai , Istrate Bogdan , Vasilescu Gabriel , Cimpoeșu Nicanor
Published: December 2022

An usual material, EN-GJL-250 cast iron, used for automotive braking systems, was covered with a ceramic material (105NS-1 aluminium oxide) using an industrial deposition system (Sulzer Metco). The main reason was to improve the corrosion and wear (friction) resistance properties of the cast-iron. Samples were prepared by mechanical grinding and sandblasting before the deposition. We applied two and four passes (around 12–15 µm by layer) each at 90° obtaining ceramic coatings of 30 respectively 60 µm. The surface of the samples (with ceramic coatings) was investigated using scanning electron microscopy (SEM), dispersive energy spectroscopy (EDS) and X-ray diffraction (XRD). Scratch and micro-hardness tests were performed using CETR-UMT-2 micro-tribometer equipment. The better corrosion resistance of the base material was obtained by applying the ceramic coating. The results present a better corrosion resistance and a higher coefficient of friction of the coated samples.
Magnetization Processes in Metallic Glass Based on Iron of FeSiB Type
Authors: Stokłosa Zbigniew , Kwapuliński Piotr , Karolus Małgorzata
Published: December 2022

In the present paper, the magnetization processes in amorphous alloys based on iron are discussed in detail. Our main goal was to measure the stabilization energy connected with the presence of microvoids (frozen during rapid cooling from the liquid phase) and to determine the interaction energy of relaxators with spontaneous magnetization vector (the so-called wN Neel) for amorphous Fe78Si13B9 alloys. A structural analysis of the alloys using X-ray measurements at the subsequent stages of crystallization was also performed.
Evaluation of the Effect of the Addition of Hydroxyapatite on Selected Mechanical and Tribological Properties of a Flow-Type Composite
Authors: Kula Zofia , Klimek Leszek , Kopacz Karolina , Śmielak Beata
Published: December 2022

(1) Background: The aim of the study was to determine the effect of modification with sintered hydroxyapatite (HAp) on selected mechanical and tribological properties of a flow-type composite. (2) Methods: Samples in the shapes of cuboidal beams (n = 120) and cylinders (n = 120) with the proper dimensions were prepared from a standard flow-type composite and others with the addition of 2% wt., 5% wt., and 8% wt. sintered hydroxyapatite. The bending strength, compression strength, diametral compression strength, impact resistance, hardness, and tribological properties were compared. (3) Results: In all cases, it was established that an increase in the amount of HAp caused a reduction in the bending, compression, and diametral compression strength. Increasing the amount of added HAp also reduced the impact strength, hardness, and wear resistance. However, the differences were statistically insignificant. (4) Conclusions: The addition of hydroxyapatite to a flow-type composite material worsened its mechanical and tribological properties; however, the obtained values were acceptable with 2% wt. and 5% wt. HAp.
Non-Wetting and Non-Reactive Behavior of Liquid Pure Magnesium on Pure Tungsten Substrates
Authors: Terlicka Sylwia , Darłak Paweł , Sobczak Natalia , Sobczak Jerzy J.
Published: December 2022

The wetting behavior of liquid magnesium drop on pure tungsten substrates was investigated, for the first time, with the sessile drop method combined with non-contact heating and capillary purification of a Mg drop from a native oxide film. A specially designed apparatus dedicated to the investigation of the high-temperature interaction of dissimilar materials was used. The comparative experiments were performed under isothermal conditions at temperatures of 700 °C and 740 °C using two atmospheres: Ar + 5 wt.% H2 and pure Ar, respectively. During high-temperature tests for 180 s, the images of the Mg/W couples were recorded with CCD cameras (57 fps) from two directions of observation. The solidified drop/substrate couples were subjected to structural characterization using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Under the applied measurement conditions, liquid Mg revealed non-wetting behavior on W substrates (a contact angle θ > 90°). The average value of the contact angle under the flowing Ar atmosphere at 740 °C was θav = 115°, whereas it was higher under the flowing Ar + 5 wt.%. H2 atmosphere at a lower temperature of 700 °C, showing θav = 122°. Independently on employed atmosphere and temperature, SEM + EDS analysis of solidified sessile drop couples did not display any new phases and mass transfer between the Mg drop and the W substrate, whereas the presence of discontinuities at the Mg/W interface of cross-sectioned couples were well-distinguished. Non-wetting and a lack of permanent bonding between the Mg drop and W substrates have a good agreement with the Mg–W phase diagram calculated with the help of FactSage software and FTlite database, i.e., the non-reactive nature of the Mg/W couple because W does not dissolve in liquid Mg and it does not form any compounds with Mg. These findings allow for the recommendation of tungsten as a suitable refractory material for long-time contact with liquid Mg in different container-assisted methods of materials characterization as well as in liquid-assisted processing of Mg components.
The Influence of Coal Tar Pitches on Thermal Behaviour of a High-Volatile Bituminous Polish Coal
Authors: Zubkova Valentina , Strojwas Andrzej
Published: December 2022

The influence of three coal tar pitches (CTPs), having softening points at 86, 94, and 103 °C, on the thermal behaviour of a defrosted high-volatile coal during co-carbonization and co-pyrolysis was studied. The following research techniques were used: X-raying of the coked charge, TG/FT-IR, ATR and UV spectroscopies, extraction, SEM, STEM, and XRD. It was determined that CTP additives change the structure of the coal plastic layer, the thickness of its zones, and the ordering degree of the structure of semi-cokes to a different extent and independently from their softening points. The softening points of CTPs do not influence the composition and yield of volatile products emitted from blends with pitch as well as the composition, structural-chemical parameters, and topological structure of material extracted from coal blends. It is suggested that such a lack of existence of any correlation between the softening points of CTPs and the degree of their influence on the thermal behaviour of coal was caused by the presence of the atoms of metals (Fe and Zn) in the CTPs. These atoms change the course of the carbonization of the CTPs themselves and their influence on organic substance of coal in blends with CTPs.
Effects of Molarity and Storage Time of MWCNTs on the Properties of Cement Paste
Authors: Laura Echeverry-Cardona , Rafael Cabanzo , Jorge Quintero-Orozco , Harvi Alirio Castillo-Cuero , Laura Victoria Rodríguez-Restrepo , Elisabeth Restrepo-Parra
Published: December 2022

Nowadays, nanomaterials in cement pastes are among the most important topics in the cement industry because they can be used for several applications. For this reason, this work presents a study about the influence of changing the molarity of dispersed multiple wall carbon nanotubes (MWCNTs) and varying the number of storage days on the mechanical properties of the cement paste. To achieve this objective, dispersions of 0.35% MWCNTs, varying the molarity of the surfactant as 10 mM, 20 mM, 40 mM, 60 mM, 80 mM, and 100 mM, were performed. The mixture of materials was developed using the sonication process; furthermore, materials were analyzed using UV-Vis, Z-potential, and Raman spectroscopy techniques. Materials with a molarity of 10 mM exhibited the best results, allowing them to also be stored for four weeks. Regarding the mechanical properties, an increase in the elastic modulus was observed when MWCNTs were included in the cement paste for all storage times. The elastic modulus and the maximum stress increased as the storage time increased.
Study on Preparation and Properties of Glass Fibre Fabric Reinforced Polyphenylene Sulphide Composites
Authors: Shao Lingda , Huang Jinbo , Feng Xuhuang , Sun Zeyu , Qiu Yingjie , Tian Wei , Zhu Chengyan
Published: December 2022

In this paper, glass fiber fabric reinforced polyphenylene sulfide composites were prepared by hot pressing. The effects of glass fibre modification and hot pressing temperature on the properties of the composites were investigated using a scanning electron microscope, infrared spectrometer, universal testing machine, and DIGEYE digital imaging colour measurement system. The results show that after the treatment with a silane coupling agent, the silane coupling agent was more uniformly distributed on the surface of the glass fibres, and the bonding effect between the glass fibre fabric and polyphenylene sulphide was significantly improved. The strength of the composites increased and then decreased with the increase of hot pressing temperature, and the surface colour of the composites became darker and darker. When the hot-pressing temperature is 310 °C, the mechanical properties of glass fabric-reinforced polyphenylene sulfide composites are at their best, the tensile strength reaches 51.9 MPa, and the bending strength reaches 78 MPa.
Processing and Properties of Tungsten-Steel Composites and FGMs Prepared by Spark Plasma Sintering
Authors: Matějíček Jiří , Mušálek Radek , Dlabáček Zdeněk , Klevarová Veronika , Kocmanová Lenka
Published: December 2022

Tungsten is the prime candidate material for the plasma-facing components of fusion reactors. For the joining of tungsten armor to the cooling system or support structure, composites or graded interlayers can be used to reduce the stress concentration at the interface. These interlayers can be produced by several technologies. Among these, spark plasma sintering appears advantageous because of its ability to fabricate fully dense parts at lower temperatures and in a shorter time than traditional powder metallurgy techniques, thanks to the concurrent application of temperature, pressure, and electrical current. In this work, spark plasma sintering of tungsten-steel composites and functionally graded layers (FGMs) was investigated. As a first step, pure tungsten and steel powders of different sizes were sintered at a range of temperatures to find a suitable temperature window for fully dense compacts. Characterization of the sintered compacts included structure (by SEM); porosity (by the Archimedean method and image analysis); thermal diffusivity (by the flash method) and mechanical properties (microhardness and flexural strength). Compacts with practically full density and fine grains were obtained; while the temperature needed to achieve full sintering decreased with decreasing powder size (down to about 1500 °C for the 0.4 μm powder). For fully sintered compacts, the hardness and thermal diffusivity increased with decreasing powder size. Composites with selected tungsten/steel ratios were produced at several conditions and characterized. At temperatures of 1100 °C or above, intermetallic formation was observed in the composites; nevertheless, without a detrimental effect on the mechanical strength. Finally, the formation of graded layers and tungsten-steel joints in various configurations was demonstrated.
Mechanical Behaviour and Impact of Various Fibres Embedded with Eggshell Powder Epoxy Resin Biocomposite
Authors: Sivakumar Aburpa Avanachari , Sankarapandian Sankarasabapathi , Avudaiappan Siva , Flores Erick I. Saavedra
Published: December 2022

Natural fiber composites are becoming an alternate material to synthetic fiber composites, and the use of eggshell bio-filler has been explored in polymer composites as environmental protection. Jute, coir, and sisal fibers were utilized in this research to make composites out of natural fibers. Polymer composites were made using epoxy resin with different amounts of eggshell powder (ESP) as fillers (2%, 4%, 6%, 8%, and 10% of weight). The mechanical and biodegradability properties of the synthesized composites were investigated. The testing results showed that composites with an optimum percentage of 6% ESP as filler improved mechanical characteristics significantly in all three fiber composites. Among the three fibers, coir fiber with 6% ESP added showed a substantial increase in tensile, flexural, impact, and hardness strength properties by 34.64%, 48.50%, 33.33%, and 35.03%, respectively. In addition, the percentage weight loss of coir fiber composites at 9 weeks is noteworthy in terms of biodegradability testing. As a result, epoxy composites containing eggshell fillers could be employed in applications requiring better tensile, flexural, impact, and hardness strength.
A Modified Two-Relaxation Thermoelastic Model for a Thermal Shock of Rotating Infinite Medium
Authors: Aljadani Maryam H. , Zenkour Ashraf M.
Published: December 2022

A unified form of thermoelasticity theory that contains three familiar generalized thermoelasticity. The Lord–Shulman theory, Green–Lindsay theory, and the classical one can be outlined in this form. The field quantities of a rotating/non-rotating half-space with and without the effect of the decay parameter can be obtained due to the unified thermoelasticity theory. The present medium is subjected to a time-dependent thermal shock taking into account that the magnitude of the thermal shock wave is not totally fixed but decaying over time. A special case of a thermal shock waveform with constant magnitude may be considered. The field quantities such as temperature, displacements, and stresses of the present problem are analytically obtained. Some plots of these field variables are presented in two- and three-dimensional illustrations in the context of refined theories.