The 2023 MDPI Annual Report has
been released!
 
19 pages, 1895 KiB  
Article
Detection and Classification of Rolling Bearing Defects Using Direct Signal Processing with Deep Convolutional Neural Network
by Maciej Skowron, Oliwia Frankiewicz, Jeremi Jan Jarosz, Marcin Wolkiewicz, Mateusz Dybkowski, Sebastien Weisse, Jerome Valire, Agnieszka Wyłomańska, Radosław Zimroz and Krzysztof Szabat
Electronics 2024, 13(9), 1722; https://doi.org/10.3390/electronics13091722 (registering DOI) - 29 Apr 2024
Abstract
Currently, great emphasis is being placed on the electrification of means of transportation, including aviation. The use of electric motors reduces operating and maintenance costs. Electric motors are subjected to various types of damage during operation, of which rolling bearing defects are statistically [...] Read more.
Currently, great emphasis is being placed on the electrification of means of transportation, including aviation. The use of electric motors reduces operating and maintenance costs. Electric motors are subjected to various types of damage during operation, of which rolling bearing defects are statistically the most common. This article focuses on presenting a diagnostic tool for bearing conditions based on mechanic vibration signals using convolutional neural networks (CNN). This article presents an alternative to the well-known classical diagnostic tools based on advanced signal processing methods such as the short-time Fourier transform, the Hilbert–Huang transform, etc. The approach described in the article provides fault detection and classification in less than 0.03 s. The proposed structures achieved a classification accuracy of 99.8% on the test set. Special attention was paid to the process of optimizing the CNN structure to achieve the highest possible accuracy with the fewest number of network parameters. Full article
14 pages, 948 KiB  
Review
Composite Nanomaterials Based on Polymethylmethacrylate Doped with Carbon Nanotubes and Nanoparticles: A Review
by Lusine Elbakyan and Irina Zaporotskova
Polymers 2024, 16(9), 1242; https://doi.org/10.3390/polym16091242 (registering DOI) - 29 Apr 2024
Abstract
Composite polymer materials have high strength and lightness, which makes them attractive for use in a variety of structures and products. The present article contains an overview of modern works devoted to the production of composite materials based on poly(methyl methacrylate) (PMMA) with [...] Read more.
Composite polymer materials have high strength and lightness, which makes them attractive for use in a variety of structures and products. The present article contains an overview of modern works devoted to the production of composite materials based on poly(methyl methacrylate) (PMMA) with improved characteristics. The possibility of obtaining such materials can be a key area for creating more efficient and durable products in various industries. Various methods were considered to improve the characteristics of PMMA by doping the polymer matrix with carbon nanotubes (CNTs), graphite, nanohydroxyapatite particles, micro-zirconia nanoparticles, titanium dioxide, etc. The possibilities of using the obtained composite materials in various industries such as aviation, automotive, construction, medical and others are discussed. This article also presents the results of our own research on the mechanisms of interaction of PMMA with single-layer CNTs, leading to the creation of a composite polymer system “PMMA+CNT”, achieved using the modern quantum chemical method DFT. This article presents a review of the recent research on the effect of CNTs on the mechanical and electrically conductive properties of nanocomposite materials. The outcomes of this study can be important for the development of science and technology in various fields, from fundamental chemistry to applied scientific research. Full article
(This article belongs to the Special Issue Carbon/Polymer Composite Materials)
21 pages, 5940 KiB  
Article
Sub-Nyquist SAR Imaging and Error Correction Via an Optimization-Based Algorithm
by Wenjiao Chen, Li Zhang, Xiaocen Xing, Xin Wen and Qiuxuan Zhang
Sensors 2024, 24(9), 2840; https://doi.org/10.3390/s24092840 (registering DOI) - 29 Apr 2024
Abstract
Sub-Nyquist synthetic aperture radar (SAR) based on pseudo-random time–space modulation has been proposed to increase the swath width while preserving the azimuthal resolution. Due to the sub-Nyquist sampling, the scene can be recovered by an optimization-based algorithm. However, these methods suffer from some [...] Read more.
Sub-Nyquist synthetic aperture radar (SAR) based on pseudo-random time–space modulation has been proposed to increase the swath width while preserving the azimuthal resolution. Due to the sub-Nyquist sampling, the scene can be recovered by an optimization-based algorithm. However, these methods suffer from some issues, e.g., manually tuning difficulty and the pre-definition of optimization parameters, and a low signal–noise ratio (SNR) resistance. To address these issues, a reweighted optimization algorithm, named pseudo-ℒ0-norm optimization algorithm, is proposed for the sub-Nyquist SAR system in this paper. A modified regularization model is first built by applying the scene prior information to nearly acquire the number of nonzero elements based on Bayesian estimation, and then this model is solved by the Cauchy–Newton method. Additionally, an error correction method combined with our proposed pseudo-ℒ0-norm optimization algorithm is also present to eliminate defocusing in the motion-induced model. Finally, experiments with simulated signals and strip-map TerraSAR-X images are carried out to demonstrate the effectiveness and superiority of our proposed algorithm. Full article
(This article belongs to the Special Issue Sensing and Signal Analysis in Synthetic Aperture Radar Systems)
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24 pages, 10644 KiB  
Article
Enhanced Bone Healing in Critical-Sized Rabbit Femoral Defects: Impact of Helical and Alternate Scaffold Architectures
by Iván Alonso-Fernández, Håvard Jostein Haugen, Liebert Parreiras Nogueira, Miriam López-Álvarez, Pío González, Mónica López-Peña, Antonio González-Cantalapiedra and Fernando Muñoz-Guzón
Polymers 2024, 16(9), 1243; https://doi.org/10.3390/polym16091243 (registering DOI) - 29 Apr 2024
Abstract
This study investigates the effect of scaffold architecture on bone regeneration, focusing on 3D-printed polylactic acid–bioceramic calcium phosphate (PLA-bioCaP) composite scaffolds in rabbit femoral condyle critical defects. We explored two distinct scaffold designs to assess their influence on bone healing and scaffold performance. [...] Read more.
This study investigates the effect of scaffold architecture on bone regeneration, focusing on 3D-printed polylactic acid–bioceramic calcium phosphate (PLA-bioCaP) composite scaffolds in rabbit femoral condyle critical defects. We explored two distinct scaffold designs to assess their influence on bone healing and scaffold performance. Structures with alternate (0°/90°) and helical (0°/45°/90°/135°/180°) laydown patterns were manufactured with a 3D printer using a fused deposition modeling technique. The scaffolds were meticulously characterized for pore size, strut thickness, porosity, pore accessibility, and mechanical properties. The in vivo efficacy of these scaffolds was evaluated using a femoral condyle critical defect model in eight skeletally mature New Zealand White rabbits. Then, the results were analyzed micro-tomographically, histologically, and histomorphometrically. Our findings indicate that both scaffold architectures are biocompatible and support bone formation. The helical scaffolds, characterized by larger pore sizes and higher porosity, demonstrated significantly greater bone regeneration than the alternate structures. However, their lower mechanical strength presented limitations for use in load-bearing sites. Full article
(This article belongs to the Special Issue Polymeric Materials in 3D Printing)
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11 pages, 506 KiB  
Article
Individualizing Surveillance after Endovascular Aortic Repair Using a Modular Imaging Algorithm
by Amun Georg Hofmann, Irene Mlekusch, Georg Wickenhauser, Corinna Walter, Fadi Taher and Afshin Assadian
Diagnostics 2024, 14(9), 930; https://doi.org/10.3390/diagnostics14090930 (registering DOI) - 29 Apr 2024
Abstract
Objectives: Surveillance after endovascular aortic repair (EVAR) and fenestrated EVAR (FEVAR) is mainly directed by one-size-fits-all approaches instead of personalized decision making, even though treatment strategies and often endografts themselves are tailor-made to adjust for individual patients. We propose a modular imaging algorithm [...] Read more.
Objectives: Surveillance after endovascular aortic repair (EVAR) and fenestrated EVAR (FEVAR) is mainly directed by one-size-fits-all approaches instead of personalized decision making, even though treatment strategies and often endografts themselves are tailor-made to adjust for individual patients. We propose a modular imaging algorithm that escalates surveillance imaging based on invasiveness and need. Materials and Methods: In this retrospective observational study of single-center data, results of a modular imaging algorithm were analyzed. The algorithm is characterized by initiating the examination with standard B-mode then transitioning to Duplex ultrasound, B-Flow, and CEUS. Additional CT(A) studies are conducted where required. The study population included both patients receiving EVAR or FEVAR. A comparative analysis was conducted regarding endoleak detection. Results: The study population included 28 patients receiving EVAR and 40 patients receiving FEVAR. They accounted for 101 follow-up visits, which led to 431 distinct imaging studies. CEUS has the highest endoleak detection rate, followed by CTA and B-Flow. Duplex ultrasound and B-Flow resulted in 0 and 1 false positive cases, respectively, considering CEUS the reference standard. In a select group of six patients, CEUS was omitted after endoleaks were displayed by Duplex ultrasound or B-Flow, leading to a successful type II coiling and no aneurysm-related adverse events. Conclusions: The proposed modular algorithm showed great potential to incorporate principles of personalized medicine in surveillance after endovascular aortic treatment. Since Duplex ultrasound and B-Flow rarely cause false positive endoleaks, more resource-intensive and invasive imaging studies such as CEUS and CTA can be omitted after positive identification. Full article
(This article belongs to the Special Issue Current Challenges and Perspectives of Ultrasound)
17 pages, 1283 KiB  
Article
Towards a Model of Snow Accretion for Autonomous Vehicles
by Mateus Carvalho, Sadegh Moradi, Farimah Hosseinnouri, Kiran Keshavan, Eric Villeneuve, Ismail Gultepe, John Komar, Martin Agelin-Chaab and Horia Hangan
Atmosphere 2024, 15(5), 548; https://doi.org/10.3390/atmos15050548 (registering DOI) - 29 Apr 2024
Abstract
Snow accumulation on surfaces exposed to adverse weather conditions has been studied over the years due to a variety of problems observed in different industry sectors, such as aeronautics and wind and civil engineering. With the growing interest in autonomous vehicles (AVs), this [...] Read more.
Snow accumulation on surfaces exposed to adverse weather conditions has been studied over the years due to a variety of problems observed in different industry sectors, such as aeronautics and wind and civil engineering. With the growing interest in autonomous vehicles (AVs), this concern extends to advanced driver-assistance systems (ADAS). Weather stressors, such as snow and icing, negatively influence the sensor functionality of AVs, and their autonomy is not guaranteed by manufacturers during episodes of intense weather precipitation. As a basis for mitigating the negative effects caused by heavy snowfall, models need to be developed to predict snow accumulation over critical surfaces of AVs. The present work proposes a framework for the study of snow accumulation on road vehicles. Existing icing and snow accretion models are reviewed, and adaptations for automotive applications are discussed. Based on the new capabilities developed by the Weather on Wheels (WoW) program at Ontario Tech University, a model architecture is proposed in order to progress toward adequate snow accretion predictions for autonomous vehicle operating conditions, and preliminary results are presented. Full article
(This article belongs to the Special Issue Sensitivity of Local Numerical Weather Prediction Models)
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12 pages, 295 KiB  
Review
Unsteady and Inhomogeneous Turbulent Fluctuations around Isotropic Equilibrium
by Wouter J. T. Bos
Atmosphere 2024, 15(5), 547; https://doi.org/10.3390/atmos15050547 (registering DOI) - 29 Apr 2024
Abstract
Extracting statistics for turbulent flows directly from the Navier–Stokes equations poses a formidable challenge, particularly when dealing with unsteady or inhomogeneous flows. However, embracing Kolmogorov’s inertial range spectrum for isotropic turbulence as a dynamic equilibrium provides a conceptual starting point for perturbation theory. [...] Read more.
Extracting statistics for turbulent flows directly from the Navier–Stokes equations poses a formidable challenge, particularly when dealing with unsteady or inhomogeneous flows. However, embracing Kolmogorov’s inertial range spectrum for isotropic turbulence as a dynamic equilibrium provides a conceptual starting point for perturbation theory. We review theoretical results, combining perturbation approaches, and phenomenological turbulence closures, which allow us to gain valuable insights into the statistics of unsteady and inhomogeneous turbulence. Additionally, we extend the ideas to the case of the mixing of a passive scalar. Full article
(This article belongs to the Special Issue Isotropic Turbulence: Recent Advances and Current Challenges)
13 pages, 338 KiB  
Article
Design of Multi-Chain Traceability Model for Pepper Products Based on Traceability Code
by Wenxuan Jin, Mingjun Zheng and Pingzeng Liu
Appl. Sci. 2024, 14(9), 3809; https://doi.org/10.3390/app14093809 (registering DOI) - 29 Apr 2024
Abstract
In the specific application scenario of pepper product supply chain traceability, with the advancement of pepper product production, the expansion of links, and the increase of nodes, the quantity of data will become more and more enormous. The single-chain model is less efficient [...] Read more.
In the specific application scenario of pepper product supply chain traceability, with the advancement of pepper product production, the expansion of links, and the increase of nodes, the quantity of data will become more and more enormous. The single-chain model is less efficient for querying if the data are all stored into the same blockchain. In order to improve the efficiency of blockchain data querying, this paper proposes a traceability model with one main chain and multiple side chain structures, which separate the uplinked data from each link and use multi-chain transactions to improve the efficiency of data queries. This model builds an indexing mechanism with a product traceability code, using one main chain and multiple side chains. The main and side chains form a one-to-many mapping relationship, storing the mapping relationship between the traceability code and the transaction address of the side chain traceability information in the main chain. This enables information to travel through the main chain traversal query based on the mapping relationship and then query the direct index out of the side chain , to achieve fast traceability query and improve the efficiency of querying. Full article
(This article belongs to the Special Issue Engineering of Smart Agriculture—2nd Edition)
10 pages, 444 KiB  
Entry
Personal Development of Doctoral Students
by Deborah M. Riby and Simon Rees
Encyclopedia 2024, 4(2), 743-752; https://doi.org/10.3390/encyclopedia4020047 (registering DOI) - 29 Apr 2024
Definition
Personal development refers to the process of increasing one’s self-awareness, associated increases of self-esteem, increasing skills, and fulfilling one’s aspirations. The current paper reflects on these elements within the doctoral journey, for PhD students within the UK Higher Education system. The paper makes [...] Read more.
Personal development refers to the process of increasing one’s self-awareness, associated increases of self-esteem, increasing skills, and fulfilling one’s aspirations. The current paper reflects on these elements within the doctoral journey, for PhD students within the UK Higher Education system. The paper makes particular reference to frameworks to encourage and capture personal development needs and supervision or coaching styles that may be used to encourage a continual reflection of personal development throughout the doctorate. Full article
(This article belongs to the Collection Doctoral Supervision)
10 pages, 505 KiB  
Review
Should We Rule out Celiac Disease in Recurrent Headache Disorders? A Review of the Literature
by Lorenzo Perilli, Samanta Carbone, Luca Franco Novelletto, Andrea Santangelo, Maria Rosaria Curcio, Federica Lotti and Salvatore Grosso
J. Clin. Med. 2024, 13(9), 2615; https://doi.org/10.3390/jcm13092615 (registering DOI) - 29 Apr 2024
Abstract
Recurrent headaches, encompassing migraine and tension-type headaches, represent prevalent conditions affecting individuals across different age groups, exerting a substantial influence on daily functioning and quality of life. Headaches serve as common manifestations of underlying health issues. Among these, celiac disease, an autoimmune disorder [...] Read more.
Recurrent headaches, encompassing migraine and tension-type headaches, represent prevalent conditions affecting individuals across different age groups, exerting a substantial influence on daily functioning and quality of life. Headaches serve as common manifestations of underlying health issues. Among these, celiac disease, an autoimmune disorder activated by gluten consumption, has emerged as a noteworthy concern. Recent research indicates a correlation between celiac disease and heightened susceptibility to headaches, particularly migraines. Celiac disease (CD) is an immune-mediated systemic, widespread disorder presenting a heterogeneous constellation of symptoms with a relatively easy diagnosis and therapy. Among signs and symptoms exhibited in celiac disease patients, headache is one of the most common neurological issues addressed among both adults and children. Headache disorders and CD are highly prevalent in the general population; for this reason, any causal association between these conditions and the role of a gluten-free diet (GFD) has been debated. The aim of this manuscript is to review the current scientific literature regarding the potential association between CD and headaches and the beneficial effects of a GFD. Among the various authors, in our opinion, the current state of the evidence suggests a significant role for the early screening of CD during the initial diagnosis of recurrent headaches, either in adults or children. Full article
(This article belongs to the Special Issue Migraines: Diagnosis and Treatment)
21 pages, 5082 KiB  
Article
Analysis of the Synchronized Locking Dynamic Characteristics of a Dual-Sidestay Main Landing Gear Retraction Mechanism
by Zhipeng Zhang, Shengxiao Wu, He Zhu, Hong Nie and Xiaohui Wei
Aerospace 2024, 11(5), 356; https://doi.org/10.3390/aerospace11050356 (registering DOI) - 29 Apr 2024
Abstract
As an advanced design technology for large wide-body airliners, the three-dimensional (3D) dual-sidestay (DSS) landing gear retraction mechanism can share the ground loads transferred by the landing gear, reducing the load on the wings. However, the addition of a strut system may significantly [...] Read more.
As an advanced design technology for large wide-body airliners, the three-dimensional (3D) dual-sidestay (DSS) landing gear retraction mechanism can share the ground loads transferred by the landing gear, reducing the load on the wings. However, the addition of a strut system may significantly impact the synchronous locking performance of the landing gear with extremely high sensitivity. To study this impact pattern, both a rigid–flexible-coupling dynamic model of DSS landing gear considering joint clearance and node deviation and a synchronous locking test platform are established in this paper, and the simulation model is validated through the experimental results. Based on the simulation model, this paper conducts a detailed study on the influence of different node deviations and joint clearance on the synchronous locking dynamic characteristics of the DSS landing gear. The results show that, as the node deviation increases, the locking of the lock link gradually lags until one side cannot be fully locked; the structural clearance has a smaller impact on the synchronous locking of the landing gear. The feasible region of parameters satisfying the synchronous locking condition is given, which provides a basis and support for the parameter design of dual-sidestay retraction mechanisms. Full article
(This article belongs to the Section Aeronautics)
17 pages, 741 KiB  
Article
The Impact of Cardiorespiratory and Metabolic Parameters on Match Running Performance (MRP) in National-Level Football Players: A Multiple Regression Analysis
by Radivoje Radaković, Borko Katanić, Mima Stanković, Bojan Mašanović and Suzana Žilić Fišer
Appl. Sci. 2024, 14(9), 3807; https://doi.org/10.3390/app14093807 (registering DOI) - 29 Apr 2024
Abstract
The aim of the study was to examine the association between cardiorespiratory and metabolic parameters and match running performance (MRP) in highly trained football players. The sample of participants consisted of 41 national-level football players (aged 23.20 ± 3.40 yrs, body height 182.00 [...] Read more.
The aim of the study was to examine the association between cardiorespiratory and metabolic parameters and match running performance (MRP) in highly trained football players. The sample of participants consisted of 41 national-level football players (aged 23.20 ± 3.40 yrs, body height 182.00 ± 5.15 cm, and body mass 76.86 ± 6.06 kg) from the Serbian Super league. For the purposes of this research, the following measurements were applied. A maximal multistage progressive treadmill test, with a direct measurement of maximal oxygen consumption (VO2max) (using Fitmate MED, Cosmed, Rome, Italy) was conducted, alongside continuous heart rate monitoring. Capillary blood samples were taken from the hyperemic area using specific test strips, and, after sample collection, lactate concentration was immediately determined using a lactate analyzer. MRP variables were analyzed according to the BioIRC model of motion structure analysis, based on existing standards for profiling movement intensity. The results of multiple regression analysis indicated an association between cardiac parameters and total distance (R2 = 54.3%, p = 0.000), high-speed running (R2 = 46.4%, p = 0.000), and jogging (R2 = 33.6%, p = 0.004). Regression analysis revealed an association between cardiorespiratory parameters and total distance (R2 = 24.8%, p = 0.014), and high-speed running (R2 = 20%, p = 0.039). Meanwhile, no association was found between lactate concentration and running performance. The explanation for these regression analysis results is based on the observation that functional abilities represent significant potential for expressing movement performance, a crucial condition for success in football. Full article
(This article belongs to the Special Issue Human Performance and Health in Sport and Exercise)
17 pages, 646 KiB  
Article
Combining Zinc Biofortification and Native Trichoderma Inoculation Strategies for Subterranean Clover
by Carlos García-Latorre, Rocío Velázquez, Alejandro Hernández, Paula Tejero and Maria J. Poblaciones
Sustainability 2024, 16(9), 3730; https://doi.org/10.3390/su16093730 (registering DOI) - 29 Apr 2024
Abstract
Using beneficial microorganisms along with sustainable strategies such as agronomic biofortification offers eco-friendly alternatives to combat climate change in ecosystems like dehesas. This study analyzes the combined effects of four wild Trichoderma spp. isolated from Extremadura, Spain (T. koningiopsis, two T. [...] Read more.
Using beneficial microorganisms along with sustainable strategies such as agronomic biofortification offers eco-friendly alternatives to combat climate change in ecosystems like dehesas. This study analyzes the combined effects of four wild Trichoderma spp. isolated from Extremadura, Spain (T. koningiopsis, two T. gamsii, and T. koningii, with negative and positive controls) and four Zn biofortification treatments (no Zn application; soil application of 5 mg of ZnSO4·7H2O per kg of soil, labeled soil Zn; two foliar applications of 5 mL 0.5% ZnSO4·7H2O, labeled foliar Zn; and soil + foliar combination, labeled SF) on Trifolium subterraneum performance. The combination of T. koningiopsis and T. gamsii with foliar Zn improved plant growth by up to 34.4%. Zinc accumulation was about 30% higher when T. gamsii and T. koningii were applied with SF, and their inoculation resulted in a 2.5-fold increase in ash. Trichoderma spp. affected nodulation differently; both T. gamsii inhibited nodulation by 24%, whereas neither T. koningiopsis nor T. koningii showed differences from the controls. These results highlight the potential of combining beneficial microorganisms with biofortification strategies to address nutrient deficiencies and improve agricultural sustainability. However, the complex interactions between both factors underscore the importance of strain selection and call for further research to optimize application strategies and elucidate underlying mechanisms. Full article
(This article belongs to the Special Issue Sustainability of Agriculture: The Impact of Climate Change on Crops)
29 pages, 760 KiB  
Article
A View on the Chemical and Biological Attributes of Five Edible Fruits after Finishing Their Shelf Life: Studies on Caco-2 Cells
by Lucia Camelia Pirvu, Nicoleta Rusu, Cristina Bazdoaca, Elena Androne, Georgeta Neagu and Adrian Albulescu
Int. J. Mol. Sci. 2024, 25(9), 4848; https://doi.org/10.3390/ijms25094848 (registering DOI) - 29 Apr 2024
Abstract
We studied five common perishable fruits in terms of their polyphenols dynamic, minerals distribution, scavenger activity and the effects of 50% ethanolic extracts on the viability of Caco-2 cells in vitro, over a period of time between T = 0 and T [...] Read more.
We studied five common perishable fruits in terms of their polyphenols dynamic, minerals distribution, scavenger activity and the effects of 50% ethanolic extracts on the viability of Caco-2 cells in vitro, over a period of time between T = 0 and T = 5/7 days, typically the end of their shelf life. Altogether, there were few changes found, consisting of either an increase or a decrease in their chemical and biological attributes. A slow decrease was found in the antioxidant activity in apricot (−11%), plum (−6%) and strawberry (−4%) extracts, while cherry and green seedless table grape extracts gained 7% and 2% antioxidant potency, respectively; IC50 values ranged from 1.67 to 5.93 μg GAE/μL test extract. The cytotoxicity MTS assay at 24 h revealed the ability of all 50% ethanol fruit extracts to inhibit the Caco-2 cell viability; the inhibitory effects ranged from 49% to 83% and were measured at 28 µg GAE for strawberry extracts/EES, from 22 µg to 45 µg GAE for cherry extracts/EEC, from 7.58 to 15.16 µg GAE for apricot extracts/EEA, from 12.50 to 25.70 µg GAE for plum extracts/EEP and from 21.51 to 28.68 µg GAE for green table grape extracts/EEG. The MTS anti-proliferative assay (72 h) also revealed a stimulatory potency upon the Caco-2 viability, from 34% (EEA, EEG) and 48% (EEC) to 350% (EES) and 690% (EEP); therefore fruit juices can influence intestinal tumorigenesis in humans. Full article
(This article belongs to the Collection Feature Papers in Bioactives and Nutraceuticals)
15 pages, 838 KiB  
Article
Enhanced Aquathermolysis of Water–Heavy Oil–Ethanol Catalyzed by B@Zn(II)L at Low Temperature
by Zhe Shen, Xiangqing Fang, Wenbo He, Le Zhang, Yongfei Li, Guobin Qi, Xin Xin, Bin Zhao and Gang Chen
Molecules 2024, 29(9), 2057; https://doi.org/10.3390/molecules29092057 (registering DOI) - 29 Apr 2024
Abstract
In order to study the synergistic effects of exogenous catalysts and in situ minerals in the reservoir during heavy oil aquathermolysis, in this paper, a series of simple supported transition metal complexes were prepared using sodium citrate, chloride salts and bentonite, and their [...] Read more.
In order to study the synergistic effects of exogenous catalysts and in situ minerals in the reservoir during heavy oil aquathermolysis, in this paper, a series of simple supported transition metal complexes were prepared using sodium citrate, chloride salts and bentonite, and their catalytic viscosity reduction performances for heavy oil were investigated. Bentonite complex catalyst marked as B@Zn(II)L appears to be the most effective complex. B@Zn(II)L was characterized by scanning electron microscopy (SEM), Fourier-Transform Infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and N2 adsorption–desorption isotherms. Under optimized conditions, the viscosity of the heavy oil was decreased by 88.3%. The reaction temperature was reduced by about 70 °C compared with the traditional reaction. The results of the group composition analysis and the elemental content of the heavy oil indicate that the resin and asphaltene content decreases, and the saturated and aromatic HC content increases. The results of TGA and DSC of the heavy oil show that the macromolecular substances in the heavy oil were cracked into small molecules with low boiling points by the reaction. GC-MS examination of water-soluble polar compounds post-reaction indicates that B@Zn(II)L can diminish the quantity of polar substances in heavy oil and lower the aromatic nature of these compounds. Thiophene and quinoline were utilized as model compounds to investigate the reaction mechanism. GC-MS analysis revealed that C-C, C-N and C-S bonds were cleaved during the reaction, leading to a decrease in the viscosity of heavy oil. Full article
16 pages, 4730 KiB  
Article
The Preparation and Dust Suppression Performance Evaluation of Iron Ore Tailing-Based Cementitious Composites
by Miaomiao Nie, Shefeng Li, Xuli Li, Shenxu Bao, Pei Chen, Yong Zhang, Siyu Ding and Jiale Li
Molecules 2024, 29(9), 2056; https://doi.org/10.3390/molecules29092056 (registering DOI) - 29 Apr 2024
Abstract
In order to comprehensively utilize iron ore tailings (IOTs), the possibility of using IOTs as raw materials for the preparation of cementitious composites (IOTCCs) was investigated, and IOTCC was further applied to mine interface pollution control. The mechanical properties, hydration products, wind erosion [...] Read more.
In order to comprehensively utilize iron ore tailings (IOTs), the possibility of using IOTs as raw materials for the preparation of cementitious composites (IOTCCs) was investigated, and IOTCC was further applied to mine interface pollution control. The mechanical properties, hydration products, wind erosion resistance, and freeze–thaw (F–T) cycle resistance of IOTCCs were evaluated rigorously. The activity index of iron tailings increased from 42% to 78% after grinding for 20 s. The IOTCC was prepared by blending 86% IOT, 10% ground granulated blast-furnace slag (GGBS), and 4% cement clinker. Meanwhile, the hydration products mainly comprised ettringite, calcium hydroxide, and C-S-H gel, and they were characterized via XRD, IR, and SEM. It was observed that ettringite and C-S-H gel were principally responsible for the strength development of IOTCC mortars with an increase in curing time. The results show that the kaolinite of the tailings was decomposed largely after mechanical activation, which promoted the cementitious property of IOT. Full article
(This article belongs to the Section Green Chemistry)
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23 pages, 58585 KiB  
Article
Image-Based Phenotyping Study of Wheat Growth and Grain Yield Dependence on Environmental Conditions and Nitrogen Usage in a Multi-Year Field Trial
by Stanley J. Miklavcic, Joshua Chopin and Hamid Laga
Sustainability 2024, 16(9), 3728; https://doi.org/10.3390/su16093728 (registering DOI) - 29 Apr 2024
Abstract
As the global population and resource scarcity simultaneously increase, the pressure on plant breeders and growers to maximise the effectiveness of their operations is immense. In this article, we explore the usefulness of image-based data collection and analysis of field experiments consisting of [...] Read more.
As the global population and resource scarcity simultaneously increase, the pressure on plant breeders and growers to maximise the effectiveness of their operations is immense. In this article, we explore the usefulness of image-based data collection and analysis of field experiments consisting of multiple field sites, plant varieties, and treatments. The goal of this approach is to determine whether the noninvasive acquisition and analysis of image data can be used to find relationships between the canopy traits of field experiments and environmental factors. Our results are based on data from three field trials in 2016, 2017, and 2018 in South Australia. Image data were supplemented by environmental data such as rainfall, temperature, and soil composition in order to explain differences in growth and the development of plants across field trials. We have shown that the combination of high-throughput image-based data and independently recorded environmental data can reveal valuable connections between the variables influencing wheat crop growth; meanwhile, further studies involving more field trials under different conditions are required to test hypotheses and draw statistically significant conclusions. This work highlights some of the more responsive traits and their dependencies. Full article
11 pages, 232 KiB  
Review
Sublobar Resection of Non-Small-Cell Lung Cancer: Wedge Resection vs. Segmentectomy
by Kyeong Ri Yu and Walker A. Julliard
Curr. Oncol. 2024, 31(5), 2497-2507; https://doi.org/10.3390/curroncol31050187 (registering DOI) - 29 Apr 2024
Abstract
Lung cancer is the most common cause of cancer death. The mainstay treatment for non-small-cell lung cancer (NSCLC), particularly in the early stages, is surgical resection. Traditionally, lobectomy has been considered the gold-standard technique. Sublobar resection includes segmentectomy and wedge resection. Compared to [...] Read more.
Lung cancer is the most common cause of cancer death. The mainstay treatment for non-small-cell lung cancer (NSCLC), particularly in the early stages, is surgical resection. Traditionally, lobectomy has been considered the gold-standard technique. Sublobar resection includes segmentectomy and wedge resection. Compared to lobectomy, these procedures have been viewed as a compromise procedure, reserved for those with poor cardiopulmonary function or who are poor surgical candidates for other reasons. However, with the advances in imaging and surgical techniques, the subject of sublobar resection as a curative treatment is being revisited. Many studies have now shown segmentectomy to be equivalent to lobectomy in patients with small (<2.0 cm), peripheral NSCLC. However, there is a mix of evidence when it comes to wedge resection and its suitability as a curative procedure. At this time, until more data can be found, segmentectomy should be considered before wedge resection for patients with early-stage NSCLC. Full article
17 pages, 2628 KiB  
Article
Effect of Corrosion-Induced Structural Degradation on the Ultimate Strength of a High-Tensile-Steel Ship Hull
by Nikola Momčilović, Nemanja Ilić, Milan Kalajdžić, Špiro Ivošević and Ana Petrović
J. Mar. Sci. Eng. 2024, 12(5), 745; https://doi.org/10.3390/jmse12050745 (registering DOI) - 29 Apr 2024
Abstract
Standard structural assessments of ship hulls include the evaluation of the elastic structural response. Elastic analysis neglects extreme and unpredicted loadings, which can produce catastrophic outcomes, such as the loss of the ship’s ultimate strength. Moreover, hull elements are considered unaffected by age-related [...] Read more.
Standard structural assessments of ship hulls include the evaluation of the elastic structural response. Elastic analysis neglects extreme and unpredicted loadings, which can produce catastrophic outcomes, such as the loss of the ship’s ultimate strength. Moreover, hull elements are considered unaffected by age-related degradation. Therefore, this study models and quantifies the effect of corrosion-induced structural degradation on the ultimate strength of a high-tensile-steel (HTS) cargo ship using progressive collapse and nonlinear finite element methods. Uniform and pitting corrosion are modeled through selected scenarios, which hull elements might encounter during exploitation, producing a total of 148 calculation models. The findings show that corrosion-induced degradation can significantly decrease the ultimate strength of the hull (up to 30% for the most severe scenarios assessed). Furthermore, ultimate strength decreases almost proportionally to the amount of wastage considered. It was found that stiffener corrosion has a significant effect on the total ultimate strength. This study’s aim is to emphasize the vast importance of including ultimate strength along with ageing effects in industry-standard structural assessments of large HTS ship structures, designed to last for several decades whilst exposed to excessive and unpredicted bending moments. Full article
(This article belongs to the Special Issue Failure Analysis of Marine Structure II)
16 pages, 9473 KiB  
Article
The Analysis of Present and Future Use of Non-Conventional Water Resources in Heilongjiang Province, China
by Hongcong Guo, Yingna Sun, Tienan Li, Yun Teng, He Dong, Hui Li and Gengwei Liu
Sustainability 2024, 16(9), 3727; https://doi.org/10.3390/su16093727 (registering DOI) - 29 Apr 2024
Abstract
Analyzing the development trend of non-conventional water resources and identifying the main influencing factors is the initial step toward rapidly increasing the utilization and allocation of these resources in a rational and scientific manner. This will help relieve pressure on water resources and [...] Read more.
Analyzing the development trend of non-conventional water resources and identifying the main influencing factors is the initial step toward rapidly increasing the utilization and allocation of these resources in a rational and scientific manner. This will help relieve pressure on water resources and improve the ecological environment. This study introduces the concept of comparison testing and employs advanced Dematel and Random Forest models to identify two sets of optimal indicators from a pool of nine. Based on the two best indicator sets, three prediction models—BP neural network, Particle Swarm Optimization-optimized BP neural network, and Genetic neural network—were used to forecast the future potential of non-conventional water resource use in Heilongjiang Province. The findings reveal that economic indicators are the most significant factors influencing Heilongjiang Province’s utilization of non-conventional water resources. The findings of this study help us understand the extent of development in utilizing non-conventional water resources. Full article
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43 pages, 1013 KiB  
Review
Osteoarthritis: Insights into Diagnosis, Pathophysiology, Therapeutic Avenues, and the Potential of Natural Extracts
by Chiara Coppola, Marco Greco, Anas Munir, Debora Musarò, Stefano Quarta, Marika Massaro, Maria Giulia Lionetto and Michele Maffia
Curr. Issues Mol. Biol. 2024, 46(5), 4063-4105; https://doi.org/10.3390/cimb46050251 (registering DOI) - 29 Apr 2024
Abstract
Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable [...] Read more.
Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable research strides. Presently, diagnosis heavily relies on clinician expertise and meticulous differential diagnosis to exclude other joint-affecting conditions. Therapeutic approaches for OA predominantly focus on patient education for self-management alongside tailored exercise regimens, often complemented by various pharmacological interventions primarily targeting pain alleviation. However, pharmacological treatments typically exhibit short-term efficacy and local and/or systemic side effects, with prosthetic surgery being the ultimate resolution in severe cases. Thus, exploring the potential integration or substitution of conventional drug therapies with natural compounds and extracts emerges as a promising frontier in enhancing OA management. These alternatives offer improved safety profiles and possess the potential to target specific dysregulated pathways implicated in OA pathogenesis, thereby presenting a holistic approach to address the condition’s complexities. Full article
(This article belongs to the Special Issue Molecular Research in Osteoarthritis and Osteoarticular Diseases)
22 pages, 1270 KiB  
Article
GBDT Method Integrating Feature-Enhancement and Active-Learning Strategies—Sea Ice Thickness Inversion in Beaufort Sea
by Yanling Han, Junjie Huang, Zhenling Ma, Bowen Zheng, Jing Wang and Yun Zhang
Sensors 2024, 24(9), 2836; https://doi.org/10.3390/s24092836 (registering DOI) - 29 Apr 2024
Abstract
Sea ice, as an important component of the Earth’s ecosystem, has a profound impact on global climate and human activities due to its thickness. Therefore, the inversion of sea ice thickness has important research significance. Due to environmental and equipment-related limitations, the number [...] Read more.
Sea ice, as an important component of the Earth’s ecosystem, has a profound impact on global climate and human activities due to its thickness. Therefore, the inversion of sea ice thickness has important research significance. Due to environmental and equipment-related limitations, the number of samples available for remote sensing inversion is currently insufficient. At high spatial resolutions, remote sensing data contain limited information and noise interference, which seriously affect the accuracy of sea ice thickness inversion. In response to the above issues, we conducted experiments using ice draft data from the Beaufort Sea and designed an improved GBDT method that integrates feature-enhancement and active-learning strategies (IFEAL-GBDT). In this method, the incident angle and time series are used to perform spatiotemporal correction of the data, reducing both temporal and spatial impacts. Meanwhile, based on the original polarization information, effective multi-attribute features are generated to expand the information content and improve the separability of sea ice with different thicknesses. Taking into account the growth cycle and age of sea ice, attributes were added for month and seawater temperature. In addition, we studied an active learning strategy based on the maximum standard deviation to select more informative and representative samples and improve the model’s generalization ability. The improved GBDT model was used for training and prediction, offering advantages in dealing with nonlinear, high-dimensional data, and data noise problems, further expanding the effectiveness of feature-enhancement and active-learning strategies. Compared with other methods, the method proposed in this paper achieves the best inversion accuracy, with an average absolute error of 8 cm and a root mean square error of 13.7 cm for IFEAL-GBDT and a correlation coefficient of 0.912. This research proves the effectiveness of our method, which is suitable for the high-precision inversion of sea ice thickness determined using Sentinel-1 data. Full article
14 pages, 521 KiB  
Article
Epidemiology of Respiratory Syncytial Virus Hospitalizations in Poland: An Analysis from 2015 to 2023 Covering the Entire Polish Population of Children Aged under Five Years
by Jan Mazela, Teresa Jackowska, Marcin Czech, Ewa Helwich, Oliver Martyn, Pawel Aleksiejuk, Anna Smaga, Joanna Glazewska and Jacek Wysocki
Viruses 2024, 16(5), 704; https://doi.org/10.3390/v16050704 (registering DOI) - 29 Apr 2024
Abstract
Background: Respiratory syncytial virus (RSV) is an important cause of childhood hospitalizations. The aim of the study was to estimate the rates of RSV-related hospitalizations in children aged less than 5 years in Poland. Methods: This retrospective observational cohort study was based on [...] Read more.
Background: Respiratory syncytial virus (RSV) is an important cause of childhood hospitalizations. The aim of the study was to estimate the rates of RSV-related hospitalizations in children aged less than 5 years in Poland. Methods: This retrospective observational cohort study was based on data obtained from the National Health Fund in Poland regarding all acute respiratory tract infections and RSV-coded admissions of children (age <5 years) to public hospitals between July 2015 and June 2023. Patients were stratified based on the following age groups: 0–1 month, 2–3 months, 4–6 months, 7–12 months, 13–24 months, and 25–60 months. Results: The number of RSV-related hospitalizations increased every season, both before and through the ending phase of the coronavirus disease 2019 (COVID-19) pandemic. The COVID-19 pandemic was associated with a shift in the seasonality pattern of RSV infection. Hospitalization rates per 1000 inhabitants were the highest for children aged 0–12 months, reaching 47.3 in the 2022/23 season. Within this group, the highest hospitalization rate was observed for children aged 2–3 months—94.9 in the 2022/23 season. During the ending phase of the COVID-19 pandemic, the observed increase in admission rates was 2-, 4-, and 5-fold the pre-COVID rate for children aged <12 months, 12–24 months, and 25–60 months, respectively. Conclusions: In Poland, RSV infections cause a significant burden in hospitalized children aged less than 5 years. RSV-related hospitalizations were most frequent in children aged less than 1 year. The COVID-19 pandemic was associated with a shift in the seasonality pattern of RSV infections. After the pandemic, more RSV-related hospitalizations were observed in older children (aged 13 months and older) vs. the pre-pandemic phase. Full article
(This article belongs to the Section Human Virology and Viral Diseases)

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