The 2023 MDPI Annual Report has
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27 pages, 1683 KiB  
Article
Amended Vegetation Filters as Nature-Based Solutions for the Treatment of Pharmaceuticals: Infiltration Experiments Coupled to Reactive Transport Modelling
by Raisa Gabriela Salvi-Taga, Raffaella Meffe, Virtudes Martínez-Hernández, Angel De Miguel Garcia and Irene De Bustamante
Toxics 2024, 12(5), 334; https://doi.org/10.3390/toxics12050334 (registering DOI) - 04 May 2024
Abstract
In small populations and scattered communities, wastewater treatment through vegetation filters (VFs), a nature-based solution, has proved to be feasible, especially for nutrient and organic matter removal. However, the presence of pharmaceuticals in wastewater and their potential to infiltrate through the vadose zone [...] Read more.
In small populations and scattered communities, wastewater treatment through vegetation filters (VFs), a nature-based solution, has proved to be feasible, especially for nutrient and organic matter removal. However, the presence of pharmaceuticals in wastewater and their potential to infiltrate through the vadose zone and reach groundwater is a drawback in the evaluation of VF performances. Soil amended with readily labile carbon sources, such as woodchips, enhances microbial activity and sorption processes, which could improve pharmaceutical attenuation in VFs. The present study aims to assess if woodchip amendments to a VF’s soil are able to abate concentrations of selected pharmaceuticals in the infiltrating water by quantitatively describing the occurring processes through reactive transport modelling. Thus, a column experiment using soil collected from an operating VF and poplar woodchips was conducted, alongside a column containing only soil used as reference. The pharmaceuticals acetaminophen, naproxen, atenolol, caffeine, carbamazepine, ketoprofen and sulfamethoxazole were applied daily to the column inlet, mimicking a real irrigation pattern and periodically measured in the effluent. Ketoprofen was the only injected pharmaceutical that reached the column outlet of both systems within the experimental timeframe. The absence of acetaminophen, atenolol, caffeine, carbamazepine, naproxen and sulfamethoxazole in both column outlets indicates that they were attenuated even without woodchips. However, the presence of 10,11-epoxy carbamazepine and atenolol acid as transformation products (TPs) suggests that incomplete degradation also occurs and that the effect of the amendment on the infiltration of TPs is compound-specific. Modelling allowed us to generate breakthrough curves of ketoprofen in both columns and to obtain transport parameters during infiltration. Woodchip-amended columns exhibited Kd and μw values from one to two orders of magnitude higher compared to soil column. This augmentation of sorption and biodegradation processes significantly enhanced the removal of ketoprofen to over 96%. Full article
13 pages, 3665 KiB  
Article
The Effect of Misalignment on Stress Concentration and Fatigue Life for Circumferential Weld Joints of Pipeline
by Niantao Zhang, Caiyan Deng, Zhichen Lin, Zhijiang Wang and Shaojie Wu
Metals 2024, 14(5), 545; https://doi.org/10.3390/met14050545 (registering DOI) - 04 May 2024
Abstract
Misalignment has a significant impact on the fatigue performance of circumferential weld joints in pipelines, which can significantly reduce the fatigue life. Misalignment generates a structural stress concentration on the pipeline, which proportionally reduces its fatigue strength. Moreover, due to the misalignment, the [...] Read more.
Misalignment has a significant impact on the fatigue performance of circumferential weld joints in pipelines, which can significantly reduce the fatigue life. Misalignment generates a structural stress concentration on the pipeline, which proportionally reduces its fatigue strength. Moreover, due to the misalignment, the reinforcement of the root and the transition angle of the pipeline inwall are significantly reduced, increasing its notch stress concentration factor and further reducing its fatigue performance. This work investigates the effect of misalignment on stress concentration in the circumferential welds of pipelines, and it is used to predict the fatigue life. The structural stress method is proposed in the present work, and finite element analysis technology with Abaqus is used to calculate the structural stress concentration factor kj at the root-pass toe of misaligned circumferential weld joints, and a formula for the relationship between the structural stress concentration factor kj and the misalignment is established. The total stress concentration factor k of weld joints with different misalignments under several welding processes are calculated, and are compared with the structural stress concentration factor kj. The fatigue test data of weld joints with different misalignments are studied, and it is shown that the fatigue performance could be predicted by the fitting result. Full article
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20 pages, 6641 KiB  
Article
Climate Change Responses of High-Elevation Polylepis Forests
by Larry E. Bedoya-Canas, Felipe López-Hernández and Andrés J. Cortés
Forests 2024, 15(5), 811; https://doi.org/10.3390/f15050811 (registering DOI) - 04 May 2024
Abstract
The high mountain forests on Earth are characterized by sharp environmental heterogeneity, high species endemism, and unique phenotypic adaptations. Yet, global warming is jeopardizing this ecosystem as no other as some forests may have nowhere to go beyond the mountain’s summits. One of [...] Read more.
The high mountain forests on Earth are characterized by sharp environmental heterogeneity, high species endemism, and unique phenotypic adaptations. Yet, global warming is jeopardizing this ecosystem as no other as some forests may have nowhere to go beyond the mountain’s summits. One of the most human-endangered high-elevation ecosystems is the Polylepis forest. Despite its vulnerability, forecasting climate reactions in this distinctive high mountain forest type remains a formidable challenge. Therefore, in this study, we modeled climate change responses of high-elevation allopatric Polylepis sericea and P. quadrijuga (Rosaceae) in the northern Andes. The analysis took into account VIF-prioritized bioclimatic variables for near-to-present and future (2081–2100 MPI-ESM1-2-HR) conditions. Model selection was carried out following the AUC scores of 12 MaxEnt and six machine learning algorithms. Predictive power reached 0.97 for MaxEnt’s model fc.H_rm.1 (H-1). Results indicate a moderate vulnerability of P. sericea, with a 29% loss of area in the trailing edge, due to climate change for the period 2081–2100. On the other hand, P. quadrijuga is likely to experience even larger distribution losses, up to 99%, for the same period. The findings of this study suggest that P. quadrijuga, as compared to P. sericea, exhibits a restricted ability to maintain the corresponding habitat requirements in the face of climatic change. Higher niche specialization of P. quadrijuga in the environmentally heterogeneous Eastern Cordillera contrasts with the more generalist nature of P. sericea in the topographically less complex Central Cordillera. In addition to climate change, this trend may be exacerbated by the detrimental effects of agriculture, mining, and an expanding rural population, which represent significant human-driven pressures yet to be modeled in the northern Andean highlands. Yet, based on previous studies, the historical population dynamics during the past glacial cycles suggests that range shifts could play a more significant role at deeper time scales than previously forecasted in the species’ reaction to climate change. Additionally, Polylepis forests may be able to endure at the current locations via local adaptation and plasticity, major drivers of the phenotypic variation in long-lived trees, counteracting the vulnerability scenario under a niche conservatism hypothesis. Ultimately, the modeling procedure employed in this study provides insights into the potential effects of climate change on Polylepis forests 70 years from now. Oncoming studies may consider alternative responses inherent to the gene pool of the species and the interaction with edaphic and biotic agents. We advocate for the application of comparable estimations in other high-elevation tree communities found at the tree line. Full article
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18 pages, 8221 KiB  
Article
Experimental Study on the Relationship between Time-Varying Uplift Displacement and Grout Diffusion in Sand
by Huan-Xiao Hu, Wei Cao, Chao Deng and Yu-Fan Lu
Appl. Sci. 2024, 14(9), 3922; https://doi.org/10.3390/app14093922 (registering DOI) - 04 May 2024
Abstract
Traditional model tests for soil and rock materials face challenges in observing the slurry diffusion within the soil mass, hindering the understanding of the relationship between grouting-induced ground deformation and grout diffusion. This study conducts grouting diffusion model tests using a self-developed experimental [...] Read more.
Traditional model tests for soil and rock materials face challenges in observing the slurry diffusion within the soil mass, hindering the understanding of the relationship between grouting-induced ground deformation and grout diffusion. This study conducts grouting diffusion model tests using a self-developed experimental setup on both ordinary and transparent sand. We investigate cement slurry diffusion patterns, distribution characteristics, and temporal variations in ground uplift displacement during the grouting process. By leveraging a visualization grouting model and non-intrusive displacement measurements, we directly observe and verify the changes in cement slurry diffusion and ground displacement in transparent sand. The results indicate the following: during non-steady grouting in sand, slurry diffusion progresses from low-pressure infiltration to medium-pressure compaction, culminating in high-pressure fracturing; ground uplift displacement curves exhibit a consistent “step-like” increase with grouting time, featuring accelerated growth after each step; and visualization tests reveal a strong correlation between grouting pressure, slurry diffusion, and corresponding uplift displacement. Distinct features in the grouting pressure plot align with the acceleration phases of the displacement; at a water–cement ratio (w/c) of 0.8, the stratum’s vertical deformation shows a symmetric “higher in the middle, lower on the sides” distribution. As the burial depth decreases, the stratum’s uplift displacement tends to flatten horizontally, especially at w/c = 0.8 and 1.2. Full article
(This article belongs to the Special Issue Recent Advances in Soft Soil Engineering)
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15 pages, 3451 KiB  
Article
Multiplex Detection of Fluorescent Chemokine Binding to CXC Chemokine Receptors by NanoBRET
by Justyna M. Adamska, Spyridon Leftheriotis, Reggie Bosma, Henry F. Vischer and Rob Leurs
Int. J. Mol. Sci. 2024, 25(9), 5018; https://doi.org/10.3390/ijms25095018 (registering DOI) - 04 May 2024
Abstract
NanoLuc-mediated bioluminescence resonance energy transfer (NanoBRET) has gained popularity for its ability to homogenously measure ligand binding to G protein-coupled receptors (GPCRs), including the subfamily of chemokine receptors. These receptors, such as ACKR3, CXCR4, CXCR3, play a crucial role in the regulation of [...] Read more.
NanoLuc-mediated bioluminescence resonance energy transfer (NanoBRET) has gained popularity for its ability to homogenously measure ligand binding to G protein-coupled receptors (GPCRs), including the subfamily of chemokine receptors. These receptors, such as ACKR3, CXCR4, CXCR3, play a crucial role in the regulation of the immune system, are associated with inflammatory diseases and cancer, and are seen as promising drug targets. The aim of this study was to optimize NanoBRET-based ligand binding to NLuc-ACKR3 and NLuc-CXCR4 using different fluorescently labeled chemokine CXCL12 analogs and their use in a multiplex NanoBRET binding assay of two chemokine receptors at the same time. The four fluorescent CXCL12 analogs (CXCL12-AZD488, -AZD546, -AZD594, -AZD647) showed high-affinity saturable binding to both NLuc-ACKR3 and NLuc-CXCR4, with relatively low levels of non-specific binding. Additionally, the binding of all AZDye-labeled CXCL12s to Nluc receptors was inhibited by pharmacologically relevant unlabeled chemokines and small molecules. The NanoBRET binding assay for CXCL10-AZD488 binding to Nluc-CXCR3 was also successfully established and successfully employed for the simultaneous measurement of the binding of unlabeled small molecules to NLuc-CXCR3 and NLuc-CXCR4. In conclusion, multiplexing the NanoBRET-based competition binding assay is a promising tool for testing unlabeled (small) molecules against multiple GPCRs simultaneously. Full article
(This article belongs to the Special Issue Advances in Luciferase)
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18 pages, 596 KiB  
Review
Artificial Intelligence in Urologic Robotic Oncologic Surgery: A Narrative Review
by Themistoklis Bellos, Ioannis Manolitsis, Stamatios Katsimperis, Patrick Juliebø-Jones, Georgios Feretzakis, Iraklis Mitsogiannis, Ioannis Varkarakis, Bhaskar K. Somani and Lazaros Tzelves
Cancers 2024, 16(9), 1775; https://doi.org/10.3390/cancers16091775 (registering DOI) - 04 May 2024
Abstract
With the rapid increase in computer processing capacity over the past two decades, machine learning techniques have been applied in many sectors of daily life. Machine learning in therapeutic settings is also gaining popularity. We analysed current studies on machine learning in robotic [...] Read more.
With the rapid increase in computer processing capacity over the past two decades, machine learning techniques have been applied in many sectors of daily life. Machine learning in therapeutic settings is also gaining popularity. We analysed current studies on machine learning in robotic urologic surgery. We searched PubMed/Medline and Google Scholar up to December 2023. Search terms included “urologic surgery”, “artificial intelligence”, “machine learning”, “neural network”, “automation”, and “robotic surgery”. Automatic preoperative imaging, intraoperative anatomy matching, and bleeding prediction has been a major focus. Early artificial intelligence (AI) therapeutic outcomes are promising. Robot-assisted surgery provides precise telemetry data and a cutting-edge viewing console to analyse and improve AI integration in surgery. Machine learning enhances surgical skill feedback, procedure effectiveness, surgical guidance, and postoperative prediction. Tension-sensors on robotic arms and augmented reality can improve surgery. This provides real-time organ motion monitoring, improving precision and accuracy. As datasets develop and electronic health records are used more and more, these technologies will become more effective and useful. AI in robotic surgery is intended to improve surgical training and experience. Both seek precision to improve surgical care. AI in ‘’master–slave’’ robotic surgery offers the detailed, step-by-step examination of autonomous robotic treatments. Full article
(This article belongs to the Section Cancer Causes, Screening and Diagnosis)
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18 pages, 5831 KiB  
Article
The Effects of Irradiation on the Improvement in Oxidation Behavior of MX-ODS Steel in Liquid Pb
by Yuwen Xu, Shijing Xie, Jie Qiu, Cunfeng Yao, Wei Yan, Yanfen Li, Chongdou Yang, Shaoqiang Guo, Long Gu and Di Yun
Nanomaterials 2024, 14(9), 798; https://doi.org/10.3390/nano14090798 (registering DOI) - 04 May 2024
Abstract
Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion [...] Read more.
Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion on ODS steel need to be further studied. In this work, MX-ODS steel was irradiated by Fe ions at 500 °C up to 46 dpa. Later, the as-received specimen and the irradiated specimen were used to conduct corrosion tests in oxygen-saturated Pb at 550 °C for 1 h. In the as-received specimen, discontinuous oxides penetrated by Pb and Pb in contact with steel matrix were observed, demonstrating unsatisfactory corrosion resistance of the material. However, in the irradiated specimen after corrosion experiment, a protective oxide layer formed and prevented Pb attack. The oxidation behavior differences between the two specimens can be attributed to the defects produced by irradiation and the structural discrepancy in oxides caused by the formation process. A possible mechanism of irradiation on the corrosion is discussed. In the as-received specimen, Fe atoms loss led to voids in the oxides, and lead penetrated the oxides through these voids. In the irradiated specimen, defects left by previous irradiation helped to form a more uniform oxide layer. The adhesive outer magnetite oxide and the Fe ions generated from where grain boundary oxidation developed retarded the presence of voids and made the oxide layer protective. Full article
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23 pages, 5487 KiB  
Article
Cardiorespiratory Response to Workload Volume and Ergonomic Risk: Automotive Assembly Line Operators’ Adaptations
by Dania Furk, Luís Silva, Mariana Dias, Carlos Fujão, Phillip Probst, Hui Liu and Hugo Gamboa
Appl. Sci. 2024, 14(9), 3921; https://doi.org/10.3390/app14093921 (registering DOI) - 04 May 2024
Abstract
Repetitive tasks can lead to long-term cardiovascular problems due to continuous strain and inadequate recovery. The automobile operators on the assembly line are exposed to these risks when workload volume changes according to the workstation type. However, the current ergonomic assessments focus primarily [...] Read more.
Repetitive tasks can lead to long-term cardiovascular problems due to continuous strain and inadequate recovery. The automobile operators on the assembly line are exposed to these risks when workload volume changes according to the workstation type. However, the current ergonomic assessments focus primarily on observational and, in some cases, biomechanical methods that are subjective and time-consuming, overlooking cardiorespiratory adaptations. This study aimed to analyze the cardiorespiratory response to distinct workload volumes and ergonomic risk (ER) scores for an automotive assembly line. Sixteen male operators (age = 38 ± 8 years; BMI = 25 ± 3 kg·m2) volunteered from three workstations (H1, H2, and H3) with specific work cycle duration (1, 3, and 5 min respectively). Electrocardiogram (ECG), respiratory inductance plethysmography (RIP), and accelerometer (ACC) data were collected during their shift. The results showed significant differences from the first to the last 10 min, where H3 had its SDRRi reduced (p = 0.014), H1’s phase synchrony and H2’s coordination between thoracic and abdominal movements decreased (p < 0.001, p = 0.039). In terms of ergonomic risk, the moderate-high rank showed a reduction in SDRRi (p = 0.037) and moderate-risk activities had diminished phase synchrony (p = 0.018) and correlation (p = 0.004). Thus, the explored parameters could have the potential to develop personalized workplace adaptation and risk assessment systems. Full article
(This article belongs to the Special Issue Biomechanics and Motor Control on Human Movement Analysis)
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29 pages, 33658 KiB  
Article
Mineralogical Constraints on the Pressure–Temperature Evolution of Granulites in the Bunger Hills, East Antarctica
by Ilnur A. Abdrakhmanov, Yuri L. Gulbin, Sergey G. Skublov and Olga L. Galankina
Minerals 2024, 14(5), 488; https://doi.org/10.3390/min14050488 (registering DOI) - 04 May 2024
Abstract
Spinel- and orthopyroxene-bearing metapelitic granulites exposed in the Bunger Hills, East Antarctica, have been intensively studied in recent years because they are supposed to record evidence for UHT metamorphism. Detailed petrographic observations, as well as whole rock and mineral chemistry, together with SIMS [...] Read more.
Spinel- and orthopyroxene-bearing metapelitic granulites exposed in the Bunger Hills, East Antarctica, have been intensively studied in recent years because they are supposed to record evidence for UHT metamorphism. Detailed petrographic observations, as well as whole rock and mineral chemistry, together with SIMS trace element data on quartz, garnet, and orthopyroxene, are presented for these rocks. Mineral thermobarometry, including Al-in-orthopyroxene, ternary feldspar, Ti-in-quartz, and Fe-Ti oxide solvus, has been used to quantify the UHT conditions. Based on phase equilibrium modeling, a tight clockwise P-T path has been deduced, which involves near-isobaric heating at 6–7 kbar to ~950 °C followed by near-isobaric to slightly up-pressure cooling at 5–6 kbar to ~750 °C. It is concluded that the outlined metamorphic history is characteristic of an extensional crustal regime which is also evidenced by the correlation of prograde and retrograde metamorphism with the extensional and compressional phases of major ductile deformations recognized in the region. In order to constrain the tectonic setting of the granulites, this result is discussed in the context of current views on the Mesoproterozoic evolution of the Albany-Fraser Orogen, the westernmost part of which the Bunger Hills are considered to be. Full article
(This article belongs to the Section Mineral Deposits)
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13 pages, 1914 KiB  
Article
Vaccine Effectiveness against GP-Attended Symptomatic COVID-19 and Hybrid Immunity among Adults in Hungary during the 2022–2023 Respiratory Season Dominated by Different SARS-CoV-2 Omicron Subvariants
by Judit Krisztina Horváth, Gergő Túri, Katalin Krisztalovics, Katalin Kristóf and Beatrix Oroszi
Vaccines 2024, 12(5), 496; https://doi.org/10.3390/vaccines12050496 (registering DOI) - 04 May 2024
Abstract
Hungary provides the opportunity to evaluate the effectiveness of COVID-19 vaccination in a setting where naturally acquired immunity and hybrid immunity are likely to play a greater role due to suboptimal vaccination coverage. Methods: A test-negative study was conducted during the 2022–2023 respiratory [...] Read more.
Hungary provides the opportunity to evaluate the effectiveness of COVID-19 vaccination in a setting where naturally acquired immunity and hybrid immunity are likely to play a greater role due to suboptimal vaccination coverage. Methods: A test-negative study was conducted during the 2022–2023 respiratory season at the primary care level to determine the effectiveness of at least one COVID-19 booster dose in preventing medically attended symptomatic RT-PCR-confirmed SARS-CoV-2 infection in adults. Unvaccinated patients were used as a reference group. Results: A total of 247 cases and 1073 controls were included in the analysis. CVE was 56.8% (95% CI: 11.9–78.8%) in the population aged 60 years and older and 2.3% (95% CI: −50.0–36.3%) in the younger adults against COVID-19 caused by Omicron subvariants, mainly BA.5, BQ.1, and XBB.1. Self-reported COVID-19 in the 60–365 days prior to the current illness did not confer protection against reinfection without vaccination, but together with booster vaccination, it reduced the risk of COVID-19 by 63.0% (95% CI: −28.0–89.3%) and 87.6% (95% CI: 26.4–97.9%) among the 18–59 and 60+ age groups, respectively. Conclusions: CVE against COVID-19 was moderately high in the 60+ age groups. Because of the benefit of hybrid immunity, persons with previous SARS-CoV-2 infection should still be considered for vaccination campaigns. Full article
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13 pages, 1907 KiB  
Article
Impact of Soil Factors on the Yield and Agronomic Traits of Hemerocallis citrina Baroni in the Agro-Pastoral Ecotone of Northern China
by Xingrong Ma, Lingdong Wang, Hongfen Zhu, Jingjing Peng and Rutian Bi
Agronomy 2024, 14(5), 967; https://doi.org/10.3390/agronomy14050967 (registering DOI) - 04 May 2024
Abstract
The ecologically fragile agro-pastoral ecotone in northern China is characterized by relatively poor arable land quality. Yunzhou District in Datong City, which is situated within this transitional zone, boasts over 600 years of Hemerocallis citrina Baroni cultivation. Exploring the effects of soil physicochemical [...] Read more.
The ecologically fragile agro-pastoral ecotone in northern China is characterized by relatively poor arable land quality. Yunzhou District in Datong City, which is situated within this transitional zone, boasts over 600 years of Hemerocallis citrina Baroni cultivation. Exploring the effects of soil physicochemical properties on daylily yield and related agronomic traits is essential for enhancing the ecological and economic value of dominant crops in ecologically fragile areas. Therefore, in this study, we focused on the daylily, a characteristic cash crop that is grown in the agro-pastoral ecotone in Yunzhou District. Physicochemical property measurement and yield estimation were performed using soil samples collected from 37 sites, with Spearman’s correlation analysis, one-way analysis of variance with multiple comparisons, path analysis, and stepwise regression analysis used to analyze the generated data. The results showed the following: (1) The pathway analysis of daylily yield with each agronomic trait showed that the BN and PH directly affected the yield of daylily with direct pathway coefficients of 0.844 and 0.7, respectively, whereas the SN indirectly affected the yield of daylily through the BD and PH, with indirect pathway coefficients of 0.827 and 0.566, respectively. (2) A total of four principal components were extracted for the soil factors, of which SMC, ST and BD had large loadings on PC1; OM, TN and pH had large loadings on PC2; AK had large loadings on PC3; and AP had large loadings on PC4. (3) From the principal component regression and stepwise regression, it can be seen that SMC is the most critical factor affecting the yield of daylily, as well as the related agronomic traits, and the results also show that yield prediction was affected by OM, ST, and AK, while BN was influenced by OM and ST, and SN and PH were influenced by AP. Comparing the goodness of fit and significance of the two models, it can be concluded that the stepwise regression model is the optimal model for this study. Full article
(This article belongs to the Section Plant-Crop Biology and Biochemistry)
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23 pages, 15915 KiB  
Article
Study on the Parameter Influences of Gear Tooth Profile Modification and Transmission Error Analysis
by Di Zhou, Yonglin Guo, Jian Yang and Yimin Zhang
Machines 2024, 12(5), 316; https://doi.org/10.3390/machines12050316 (registering DOI) - 04 May 2024
Abstract
Gear transmission systems are widely used to transfer energy and motion and to guarantee the accuracy of the entire machine system. The modification technique is a common method that improves the gear profile and reduces the transmission error. Based on the parametric model, [...] Read more.
Gear transmission systems are widely used to transfer energy and motion and to guarantee the accuracy of the entire machine system. The modification technique is a common method that improves the gear profile and reduces the transmission error. Based on the parametric model, a modified gear can be established for the evaluation of static and dynamic characteristics. The influences of profile modification parameters and gear parameters are investigated while changing the rules of different kinds of factors. Based on sensitive parameters, a two-stage profile modification curve is proposed to improve the performance of gear pairs. Thus, considering the time-varying mesh stiffness and backlash, a novel, dynamic modified gear model is established to analyze the dynamic performance, such as the dynamic transmission error. Based on the proposed curve, the range and amplitude of the transmission error can be decreased. Additionally, the vibration displacement and noise can be reduced to improve the running characteristics. Full article
(This article belongs to the Section Machine Design and Theory)
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22 pages, 2300 KiB  
Article
Improving the Yield and Quality of Tomato by Using Organic Fertilizer and Silicon Compared to Reducing Chemical Nitrogen Fertilization
by Fan Zhang, Yan Liu, Yi Liang, Zemin Dai, Yanli Zhao, Yu Shi, Jing Gao, Leiping Hou, Yi Zhang and Golam Jalal Ahammed
Agronomy 2024, 14(5), 966; https://doi.org/10.3390/agronomy14050966 (registering DOI) - 04 May 2024
Abstract
Essential macronutrient nitrogen (N) is crucial for plant growth and yield, but excessive chemical N fertilizer not only increases unnecessary production costs but also causes environmental pollution. Therefore, reducing N fertilizer use by increasing organic fertilizer use is crucial for sustainable agriculture. In [...] Read more.
Essential macronutrient nitrogen (N) is crucial for plant growth and yield, but excessive chemical N fertilizer not only increases unnecessary production costs but also causes environmental pollution. Therefore, reducing N fertilizer use by increasing organic fertilizer use is crucial for sustainable agriculture. In this study, we investigated the effects of three nitrogen levels—the recommended rate (N), a 20.0% reduced rate (0.8N), and a 40.0% reduced rate (0.6N)—and two levels of organic fertilizer—a normal dose (M) and a four-times the normal dose (4M)—combined with root application of the beneficial element silicon (Si) on the photosynthetic characteristics, yield, and fruit quality of the tomato cultivar ‘Tianxi No. 5’. Compared with M + N treatment, the longitudinal diameter, transverse diameter, fruit weight, and fruit yield of tomato fruit in 4M + 0.6N treatment significantly increased by 12.4%, 14.6%, 14.5%, and 12.8%, respectively, while the yield was further improved with Si application. In addition, a reduction in N fertilizer and an increase in organic fertilizer, combined with Si application, improved fruit quality parameters such as concentrations of vitamin C, lycopene, phenols, flavonoids, sucrose, fructose, etc., and promoted sugar metabolism-related enzyme activity (sucrose synthase, invertase, and sucrose phosphate synthase) and the accumulation of N in the fruit. The principal component analysis and three-factor analysis of variance (ANOVA) of the fruit quality and yield indices showed that nitrogen fertilizer, organic fertilizer, silicon fertilizer, and the interaction of the three had significant effects on the quality and yield of tomato fruits, and that the 4M + 0.6N + Si treatment had the best combined effect on the yield and quality of the tomatoes. Thus, a moderate reduction in chemical N fertilizer, combined with increased organic fertilizer and Si, could be an effective agronomic practice for improving the yield and quality of tomatoes. Full article
15 pages, 7671 KiB  
Article
Comparative Study of the Impurity Effect on SnAgCu and SnZn Solder Joints with Electrodeposited Cu
by Yu-Ju Li, Yee-Wen Yen and Chih-Ming Chen
Materials 2024, 17(9), 2149; https://doi.org/10.3390/ma17092149 (registering DOI) - 04 May 2024
Abstract
Sn-3Ag-0.5Cu (SAC305)- and Sn-9Zn-based alloys (Sn-Zn-X, X = Al, In) are lead-free solders used in the fabrication of solder joints with Cu metallization. Electroplating is a facile technology used to fabricate Cu metallization. However, the addition of functional additive molecules in the plating [...] Read more.
Sn-3Ag-0.5Cu (SAC305)- and Sn-9Zn-based alloys (Sn-Zn-X, X = Al, In) are lead-free solders used in the fabrication of solder joints with Cu metallization. Electroplating is a facile technology used to fabricate Cu metallization. However, the addition of functional additive molecules in the plating solution may result in impurity residues in the Cu electroplated layer, causing damage to the solder joints. This study investigates the impurity effect on solder joints constructed by joining various solder alloys to the Cu electroplated layers. Functional additives are formulated to fabricate high-impurity and low-impurity Cu electroplated samples. The as-joined solder joint samples are thermally aged at 120 °C and 170 °C to explore the interfacial reactions between solder alloys and Cu. The results show that the impurity effect on the interfacial reactions between SAC305 and Cu is significant. Voids are massively formed at the SAC305/Cu interface incorporated with a high impurity content, and the Cu6Sn5 intermetallic compound (IMC) grows at a faster rate. In contrast, the growth of the Cu5Zn8 IMC formed in the SnZn-based solder joints is not significantly influenced by the impurity content in the Cu electroplated layers. Voids are not observed in the SnZn-based solder joints regardless of the impurity content, indicative of an insignificant impurity effect. The discrepancy of the impurity effect is rationalized by the differences in the IMC formation and associated atomic interdiffusion in the SAC305- and SnZn-based solder joints. Full article
(This article belongs to the Section Electronic Materials)
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17 pages, 6668 KiB  
Article
The Comparison of Physical and Chemical Properties of Pellets and Briquettes from Hemp (Cannabis sativa L.)
by Kamil Roman and Emilia Grzegorzewska
Energies 2024, 17(9), 2210; https://doi.org/10.3390/en17092210 (registering DOI) - 04 May 2024
Abstract
The adaptation of lignocellulosic materials such as Cannabis sativa L. as a new renewable energy source is linked to the fact that the technology must be developed to be able to adapt to local market conditions. Bioenergy consumers are faced with this problem [...] Read more.
The adaptation of lignocellulosic materials such as Cannabis sativa L. as a new renewable energy source is linked to the fact that the technology must be developed to be able to adapt to local market conditions. Bioenergy consumers are faced with this problem because, when it comes to the selection of briquettes and pellets for energy production, there are only individual standards in place. This research is intended to provide a better understanding of hemp product potential as a new material that can be used in the production of pellets and briquettes for biofuel purpose. Nevertheless, the anisotropic raw material interferes with the compaction process and may expose a poor durability of the pellets and briquettes. The research that was conducted evaluated the conditions of the biofuels by measuring the physical and chemical parameters. The ash content, compressive strength, and durability of the samples were examined. The statistical data analysis was performed after the strength tests on the prepared samples. Full article
(This article belongs to the Special Issue Advanced Biofuels: Production, Characterization and Upgrade)
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14 pages, 3678 KiB  
Article
Mechanisms of Groundwater Damage to Overlying Rock in Goaf
by Nan Zhu, Fei Liu and Dafa Sun
Processes 2024, 12(5), 936; https://doi.org/10.3390/pr12050936 (registering DOI) - 04 May 2024
Abstract
The discontinuation of pumping and drainage activities upon the cessation of mining operations leads to the gradual accumulation of groundwater. This inflow into mined-out areas affects the properties of the rock, disturbing the previously stable goaf and exacerbating instability. In this study, we [...] Read more.
The discontinuation of pumping and drainage activities upon the cessation of mining operations leads to the gradual accumulation of groundwater. This inflow into mined-out areas affects the properties of the rock, disturbing the previously stable goaf and exacerbating instability. In this study, we advance an existing theoretical framework pertaining to the residual deformation of mines by delineating the mechanisms through which groundwater influences the degradation of the overlying strata in goaf areas. Using analogous material simulation experiments and rigorous theoretical analyses, we clarify the specific mechanisms by which groundwater causes structural damage to these regions. The deformation of overlying rock is divided into three different forms: the compressive deformation of rock, the sliding instability of rock, and the rotational instability of rock. The main contributions of this study are its refinement of the existing theory of the residual deformation of mines, an analysis of the damage mechanisms of groundwater, and suggestions regarding technical support for targeted treatment measures in affected mines. Full article
(This article belongs to the Section Chemical Processes and Systems)
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27 pages, 11580 KiB  
Article
Exploring the Efficiency of Algerian Kaolinite Clay in the Adsorption of Cr(III) from Aqueous Solutions: Experimental and Computational Insights
by Karima Rouibah, Hana Ferkous, Meniai Abdessalam-Hassan, Bencheikh Lehocine Mossab, Abir Boublia, Christel Pierlot, Amdjed Abdennouri, Ivalina Avramova, Manawwer Alam, Yacine Benguerba and Alessandro Erto
Molecules 2024, 29(9), 2135; https://doi.org/10.3390/molecules29092135 (registering DOI) - 04 May 2024
Abstract
The current study comprehensively investigates the adsorption behavior of chromium (Cr(III)) in wastewater using Algerian kaolinite clay. The structural and textural properties of the kaolinite clay are extensively characterized through a range of analytical methods, including XRD, FTIR, SEM-EDS, XPS, laser granulometry, N [...] Read more.
The current study comprehensively investigates the adsorption behavior of chromium (Cr(III)) in wastewater using Algerian kaolinite clay. The structural and textural properties of the kaolinite clay are extensively characterized through a range of analytical methods, including XRD, FTIR, SEM-EDS, XPS, laser granulometry, N2 adsorption isotherm, and TGA–DTA. The point of zero charge and zeta potential are also assessed. Chromium adsorption reached equilibrium within five minutes, achieving a maximum removal rate of 99% at pH 5. Adsorption equilibrium is modeled using the Langmuir, Freundlich, Temkin, Elovich, and Dubinin–Radushkevitch equations, with the Langmuir isotherm accurately describing the adsorption process and yielding a maximum adsorption capacity of 8.422 mg/g for Cr(III). Thermodynamic parameters suggest the spontaneous and endothermic nature of Cr(III) sorption, with an activation energy of 26.665 kJ/mol, indicating the importance of diffusion in the sorption process. Furthermore, advanced DFT computations, including COSMO-RS, molecular orbitals, IGM, RDG, and QTAIM analyses, are conducted to elucidate the nature of adsorption, revealing strong binding interactions between Cr(III) ions and the kaolinite surface. The integration of theoretical and experimental data not only enhances the understanding of Cr(III) removal using kaolinite but also demonstrates the effectiveness of this clay adsorbent for wastewater treatment. Furthermore, this study highlights the synergistic application of empirical research and computational modeling in elucidating complex adsorption processes. Full article
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22 pages, 5085 KiB  
Article
Impact of Thinning on the Yield and Quality of Eucalyptus grandis Wood at Harvest Time in Uruguay
by Fernando Resquin, Karen Baez, Sofia de Freitas, Diego Passarella, Ana Paula Coelho-Duarte and Cecilia Rachid-Casnati
Forests 2024, 15(5), 810; https://doi.org/10.3390/f15050810 (registering DOI) - 04 May 2024
Abstract
Understanding how thinning strategies impact wood quality and quantity for different purposes is of interest, given that plantation management is often based on parameters that require validation under varying growth conditions. Planted forests for solid purposes in the northern region of Urugay, western [...] Read more.
Understanding how thinning strategies impact wood quality and quantity for different purposes is of interest, given that plantation management is often based on parameters that require validation under varying growth conditions. Planted forests for solid purposes in the northern region of Urugay, western Argentina and South of Brazil are usually managed in initial stockings ranging from 800 to 1200 trees·ha−1 depending on the use of clones or seeds. Subsequent thinnings are applied (at plantation ages varying from 3 to 11 years) up to final stockings of around 200 trees·ha−1. This study evaluated contrasting thinning regimes applied early in the crop cycle, with an initial tree density of 840 trees·ha−1. Two thinning treatments were applied at 1.5 and 7.3 years, reducing tree densities to 700–400 and 400–100 trees·ha−1, respectively. Growth analyses were conducted from 1.5 to 20.8 years, considering total height, diameter at breast height, individual volume, total and commercial volume per hectare, mean annual increase, and current annual increase. At the final harvest, contrasting tree densities of 100, 250, and 400 trees·ha−1 were sampled to assess wood density and mechanical properties (bending and compression on small-scale clear samples). Individual growth and wood properties were related to a Stand Density Index to understand the effect of competition on these values. The results identified thinning regimes that resulted in the most significant individual and per-hectare growth (both in thinning and clear felling) and the optimal harvest time under specific growth conditions. We assessed the proportions of commercial logs for sawmill and pulp uses, providing valuable inputs for subsequent economic analyses of thinning regimes aiming for the most convenient combination of wood products. Wood’s physical and mechanical properties were relatively little affected by contrasting levels of competition between trees; therefore, the choice of silvicultural system will depend on production and economic criteria. Full article
(This article belongs to the Section Forest Ecology and Management)
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18 pages, 2240 KiB  
Article
Wind Shear Operation-Based Competency Assessment Model for Civil Aviation Pilots
by Fan Li, Xuezhi Xu, Jiayuan Li, Huiyun Hu, Mingda Zhao and Hong Sun
Aerospace 2024, 11(5), 363; https://doi.org/10.3390/aerospace11050363 (registering DOI) - 04 May 2024
Abstract
Undesirable meteorological conditions are typical aviation flight safety threats. Although most meteorological radar and flight augmentation computers have avionic system wind shear alarms, the preferred approach is that pilots avoid unsafe wind shear events. Therefore, effective pilot competency evaluations are needed to assess [...] Read more.
Undesirable meteorological conditions are typical aviation flight safety threats. Although most meteorological radar and flight augmentation computers have avionic system wind shear alarms, the preferred approach is that pilots avoid unsafe wind shear events. Therefore, effective pilot competency evaluations are needed to assess pilots’ abilities to deal with these events. This study developed a wind shear operation competency model that includes observable behavior indicators, sub-task decomposition, and competency check items. An adapted competency model and a quantitative data-driven competency evaluation criteria optimization method were then developed using three-dimensional competency feature modeling, after which wind shear simulation flight training data were used to verify the effectiveness of the proposed method. The competency assessment grades were significantly correlated with the results from experienced examiners with a 93.33% evaluation accuracy. The proposed quantitative data-driven competency assessment method can provide effective pilot competency assessments for a range of aviation meteorological threats. Full article
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24 pages, 1568 KiB  
Article
Novel Self-Organizing Probability Maps Applied to Classification of Concurrent Partial Discharges from Online Hydro-Generators
by Rodrigo M. S. de Oliveira, Filipe C. Fernandes and Fabrício J. B. Barros
Energies 2024, 17(9), 2208; https://doi.org/10.3390/en17092208 (registering DOI) - 04 May 2024
Abstract
In this paper, we present an unprecedented method based on Kohonen networks that is able to automatic recognize partial discharge (PD) classes from phase-resolved partial discharge (PRPD) diagrams with features of various simultaneous PD patterns. The PRPD diagrams were obtained from the stator [...] Read more.
In this paper, we present an unprecedented method based on Kohonen networks that is able to automatic recognize partial discharge (PD) classes from phase-resolved partial discharge (PRPD) diagrams with features of various simultaneous PD patterns. The PRPD diagrams were obtained from the stator windings of a real-world hydro-generator rotating machine. The proposed approach integrates classification probabilities into the Kohonen method, producing self-organizing probability maps (SOPMs). For building SOPMs, a group of PRPD diagrams, each containing a single PD pattern for training the Kohonen networks and single- and multiple-class-featured samples for obtaining final SOPMs, is used to calculate the probabilities of each Kohonen neuron to be associated with the various PD classes considered. At the end of this process, a self-organizing probability map is produced. Probabilities are calculated using distances, obtained in the space of features, between neurons and samples. The so-produced SOPM enables the effective classification of PRPD samples and provides the probability that a given PD sample is associated with a PD class. In this work, amplitude histograms are the features extracted from PRPDs maps. Our results demonstrate an average classification accuracy rate of approximately 90% for test samples. Full article
(This article belongs to the Special Issue Energy, Electrical and Power Engineering 2024)
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14 pages, 1842 KiB  
Article
Evaluation of Almond Hull and Shell Amendments across Organic Matter Management of Orchard Soils
by Leah Wolff Hartman, Ellie M. Andrews, Erini G. Galatis, Amélie C. M. Gaudin, Patrick H. Brown and Sat Darshan S. Khalsa
Soil Syst. 2024, 8(2), 51; https://doi.org/10.3390/soilsystems8020051 (registering DOI) - 04 May 2024
Abstract
Hulls and shells are an abundant by-product from almond production with potential as an organic matter amendment (OMA). A combination of incubation study and field research was conducted in 2019–2021 to evaluate the impacts of three practices in combination on orchard soils’ C [...] Read more.
Hulls and shells are an abundant by-product from almond production with potential as an organic matter amendment (OMA). A combination of incubation study and field research was conducted in 2019–2021 to evaluate the impacts of three practices in combination on orchard soils’ C and N cycling, including a 210-day period of laboratory incubation with hulls and shells, and field sampling of orchard soils with and without historic applications of green waste compost as an OMA; with hulls and shells and with and without off-ground harvest where orchard soils remain undisturbed year round. Hulls and shells increased microbial biomass carbon in the field study by 248 μg g−1 dry soil after one year (p < 0.001) and during incubation, and increased cumulative respiration in soils with and without historic OMA (p < 0.001). Historic OMA resulted in double the total soil organic carbon (SOC) and total nitrogen (TN) compared to soil without resulting in significantly higher respiration and N mineralization when amended with hulls and shells. The decomposition of hull and shell biomass following surface application progressed at similar rates in the laboratory and field (1.7 g kg−1 d−1 during incubation (R2 = 0.84) and 1.3 g kg−1 d−1 in the field trial (R2 = 0.91). Our results highlight the suitability of hulls and shells as a by-product source of OMA for improving soil health in orchards with historic OMA and transitioning to organic matter management. Full article
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12 pages, 3140 KiB  
Article
Distinguishing the Uterine Artery, the Ureter, and Nerves in Laparoscopic Surgical Images Using Ensembles of Binary Semantic Segmentation Networks
by Norbert Serban, David Kupas, Andras Hajdu, Peter Török and Balazs Harangi
Sensors 2024, 24(9), 2926; https://doi.org/10.3390/s24092926 (registering DOI) - 04 May 2024
Abstract
Performing a minimally invasive surgery comes with a significant advantage regarding rehabilitating the patient after the operation. But it also causes difficulties, mainly for the surgeon or expert who performs the surgical intervention, since only visual information is available and they cannot use [...] Read more.
Performing a minimally invasive surgery comes with a significant advantage regarding rehabilitating the patient after the operation. But it also causes difficulties, mainly for the surgeon or expert who performs the surgical intervention, since only visual information is available and they cannot use their tactile senses during keyhole surgeries. This is the case with laparoscopic hysterectomy since some organs are also difficult to distinguish based on visual information, making laparoscope-based hysterectomy challenging. In this paper, we propose a solution based on semantic segmentation, which can create pixel-accurate predictions of surgical images and differentiate the uterine arteries, ureters, and nerves. We trained three binary semantic segmentation models based on the U-Net architecture with the EfficientNet-b3 encoder; then, we developed two ensemble techniques that enhanced the segmentation performance. Our pixel-wise ensemble examines the segmentation map of the binary networks on the lowest level of pixels. The other algorithm developed is a region-based ensemble technique that takes this examination to a higher level and makes the ensemble based on every connected component detected by the binary segmentation networks. We also introduced and trained a classic multi-class semantic segmentation model as a reference and compared it to the ensemble-based approaches. We used 586 manually annotated images from 38 surgical videos for this research and published this dataset. Full article
(This article belongs to the Section Sensing and Imaging)
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16 pages, 4159 KiB  
Article
Urban Land Surface Temperature Downscaling in Chicago: Addressing Ethnic Inequality and Gentrification
by Jangho Lee, Max Berkelhammer, Matthew D. Wilson, Natalie Love and Ralph Cintron
Remote Sens. 2024, 16(9), 1639; https://doi.org/10.3390/rs16091639 (registering DOI) - 04 May 2024
Abstract
In this study, we developed a XGBoost-based algorithm to downscale 2 km-resolution land surface temperature (LST) data from the GOES satellite to a finer 70 m resolution, using ancillary variables including NDVI, NDBI, and DEM. This method demonstrated a superior performance over the [...] Read more.
In this study, we developed a XGBoost-based algorithm to downscale 2 km-resolution land surface temperature (LST) data from the GOES satellite to a finer 70 m resolution, using ancillary variables including NDVI, NDBI, and DEM. This method demonstrated a superior performance over the conventional TsHARP technique, achieving a reduced RMSE of 1.90 °C, compared to 2.51 °C with TsHARP. Our approach utilizes the geostationary GOES satellite data alongside high-resolution ECOSTRESS data, enabling hourly LST downscaling to 70 m—a significant advancement over previous methodologies that typically measure LST only once daily. Applying these high-resolution LST data, we examined the hottest days in Chicago and their correlation with ethnic inequality. Our analysis indicated that Hispanic/Latino communities endure the highest LSTs, with a maximum LST that is 1.5 °C higher in blocks predominantly inhabited by Hispanic/Latino residents compared to those predominantly occupied by White residents. This study highlights the intersection of urban development, ethnic inequality, and environmental inequities, emphasizing the need for targeted urban planning to mitigate these disparities. The enhanced spatial and temporal resolution of our LST data provides deeper insights into diurnal temperature variations, crucial for understanding and addressing the urban heat distribution and its impact on vulnerable communities. Full article
(This article belongs to the Special Issue Remote Sensing for Land Surface Temperature and Related Applications)
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