The 2023 MDPI Annual Report has
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17 pages, 523 KiB  
Article
Global Energy Transition and the Efficiency of the Largest Oil and Gas Companies
by Sami Jarboui and Hind Alofaysan
Energies 2024, 17(10), 2271; https://doi.org/10.3390/en17102271 (registering DOI) - 08 May 2024
Abstract
The challenges posed by climate change and global warming loom large, necessitating a critical initial step towards the long-term growth and the enhancement of both environmental and operational efficiency. Within the energy sector, renewable energy sources are gaining increasing prominence. Consequently, traditional oil [...] Read more.
The challenges posed by climate change and global warming loom large, necessitating a critical initial step towards the long-term growth and the enhancement of both environmental and operational efficiency. Within the energy sector, renewable energy sources are gaining increasing prominence. Consequently, traditional oil and gas companies (OGC) are undergoing a gradual transformation into comprehensive energy corporations, aligning themselves with energy transition policies. This paper examines two types of efficiency measures—operational and environmental—for the 20 largest OGC during the period of 2010–2019. Secondly, this research aims to explore the effect of the global energy transition on both environmental and operational efficiency. Based on three estimation methods, two estimation steps are used in this research. In the first step, the True Fixed Effect (TFE) model and the Battese and coelli (1995) SFA model are applied to evaluate, measure and compare the environmental and operational efficiency scores. In the second step, the TFE model and GMM approach for the dynamic panel data model are used to explore, evaluate and verify the effect of global energy transition on the environmental and operational efficiency of the largest 20 OGC in the world. The results reveal that the average operational efficiency of major OGC measured using the BC.95 model and TFE model is 66% and 85%, respectively, and the overall average level of environmental efficiency for OGC over a 10-year period is 31% (based to B.C.95 model) and 13% (based to TFE model). Our findings reveal that biofuels, solar and hydropower contribute to promote the operational and environmental efficiency of the largest 20 OGC. However, the analysis suggests that while the global energy transition significantly influences and bolsters environmental efficiency, its effect on operational efficiency among these major OGC remains less pronounced and insufficient. Full article
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13 pages, 540 KiB  
Article
On Aspects of Continuous Approximation of Diatomic Lattice
by Igor V. Andrianov, Lelya A. Khajiyeva, Askar K. Kudaibergenov and Galina A. Starushenko
Mathematics 2024, 12(10), 1456; https://doi.org/10.3390/math12101456 (registering DOI) - 08 May 2024
Abstract
This paper is devoted to the continualization of a diatomic lattice, taking into account natural intervals of wavenumber changes. Continualization refers to the replacement of the original pseudo-differential equations by a system of PDEs that provides a good approximation of the dispersion relations. [...] Read more.
This paper is devoted to the continualization of a diatomic lattice, taking into account natural intervals of wavenumber changes. Continualization refers to the replacement of the original pseudo-differential equations by a system of PDEs that provides a good approximation of the dispersion relations. In this regard, the Padé approximants based on the conditions for matching the values of the dispersion relations of the discrete and continuous models at several characteristic points are utilized. As a result, a sixth-order unconditionally stable system with modified inertia is obtained. Appropriate boundary conditions are formulated. The obtained continuous approximation accurately describes the amplitude ratios of neighboring masses. It is also shown that the resulting continuous system provides a good approximation for the natural frequencies. Full article
(This article belongs to the Special Issue Multiscale Mathematical Modeling)
25 pages, 2077 KiB  
Article
Incorporating the Third Law of Geography with Spatial Attention Module–Convolutional Neural Network–Transformer for Fine-Grained Non-Stationary Air Quality Predictive Learning
by Shaofu Lin, Yuying Zhang, Xiliang Liu, Qiang Mei, Xiaoying Zhi and Xingjia Fei
Mathematics 2024, 12(10), 1457; https://doi.org/10.3390/math12101457 (registering DOI) - 08 May 2024
Abstract
Accurate air quality prediction is paramount in safeguarding public health and addressing air pollution control. However, previous studies often ignore the geographic similarity among different monitoring stations and face challenges in dynamically capturing different spatial–temporal relationships between stations. To address this, an air [...] Read more.
Accurate air quality prediction is paramount in safeguarding public health and addressing air pollution control. However, previous studies often ignore the geographic similarity among different monitoring stations and face challenges in dynamically capturing different spatial–temporal relationships between stations. To address this, an air quality predictive learning approach incorporating the Third Law of Geography with SAM–CNN–Transformer is proposed. Firstly, the Third Law of Geography is incorporated to fully consider the geographical similarity among stations via a variogram and spatial clustering. Subsequently, a spatial–temporal attention convolutional network that combines the spatial attention module (SAM) with the convolutional neural network (CNN) and Transformer is designed. The SAM is employed to extract spatial–temporal features from the input data. The CNN is utilized to capture local information and relationships among each input feature. The Transformer is applied to capture time dependencies across long-distance time series. Finally, Shapley’s analysis is employed to interpret the model factors. Numerous experiments with two typical air pollutants (PM2.5, PM10) in Haikou City show that the proposed approach has better comprehensive performance than baseline models. The proposed approach offers an effective and practical methodology for fine-grained non-stationary air quality predictive learning. Full article
16 pages, 4366 KiB  
Article
Effect of the Inorganic Modification Mode on the Mechanical Properties of Rubber Recycled Concrete
by Leifei Liu, Jingmei Zong, Xueqian Hou and Xiaoyan Liu
Materials 2024, 17(10), 2217; https://doi.org/10.3390/ma17102217 (registering DOI) - 08 May 2024
Abstract
The reasonable and effective application of waste tires and discarded concrete in concrete is an important branch of green concrete development. This paper investigates the effects of the inorganic modification mode on the basic mechanical properties of rubber recycled concrete based on indoor [...] Read more.
The reasonable and effective application of waste tires and discarded concrete in concrete is an important branch of green concrete development. This paper investigates the effects of the inorganic modification mode on the basic mechanical properties of rubber recycled concrete based on indoor tests. Inorganic modification, such as water washing, acid washing, and alkaline washing modification, was mainly used to treat and modify rubber particles. The factors affecting the compressive strength, the splitting tensile strength, the flexural strength, the axial compressive strength, and the modulus of elasticity of modified rubber recycled concrete were analyzed. The study results show that the incorporation of recycled aggregates and rubber reduced the mechanical properties of concrete, with the compressive and splitting tensile strengths showing the greatest reductions of 27.36% and 27.24%, respectively. Three modification methods significantly improved the mechanical properties of rubber recycled concrete. The alkali washing modification method was the most effective, maximally improving the mechanical properties of rubber recycled concrete by 7.53–15.51%. The effects of the three modifications on the mechanical properties of concrete were ranked as follows: alkali washing > acid washing > water washing. This study provides a data basis for the practical application of rubber recycled concrete in engineering and a test basis for the development of green concrete. Full article
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17 pages, 958 KiB  
Article
Systematic Study of Different Types of Interactions in α-, β- and γ-Cyclodextrin: Quantum Chemical Investigation
by Imre Bakó, László Jicsinszky and Szilvia Pothoczki
Molecules 2024, 29(10), 2205; https://doi.org/10.3390/molecules29102205 (registering DOI) - 08 May 2024
Abstract
In this work, comprehensive ab initio quantum chemical calculations using the DFT level of theory were performed to characterize the stabilization interactions (H-bonding and hyperconjugation effects) of two stable symmetrical conformations of α-, β-, and γ-cyclodextrins (CDs). For this purpose, we analyzed the [...] Read more.
In this work, comprehensive ab initio quantum chemical calculations using the DFT level of theory were performed to characterize the stabilization interactions (H-bonding and hyperconjugation effects) of two stable symmetrical conformations of α-, β-, and γ-cyclodextrins (CDs). For this purpose, we analyzed the electron density using “Atom in molecules” (AIM), “Natural Bond Orbital” (NBO), and energy decomposition method (CECA) in 3D and in Hilbert space. We also calculated the H-bond lengths and OH vibrational frequencies. In every investigated CD, the quantum chemical descriptors characterizing the strength of the interactions between the H-bonds of the primary OH (or hydroxymethyl) and secondary OH groups are examined by comparing the same quantity calculated for ethylene glycol, α-d-glucose (α-d-Glcp) and a water cluster as reference systems. By using these external standards, we can characterize more quantitatively the properties of these bonds (e.g., strength). We have demonstrated that bond critical points (BCP) of intra-unit H-bonds are absent in cyclodextrins, similar to α-d-Glcp and ethylene glycol. In contrast, the CECA analysis showed the existence of an exchange (bond-like) interaction between the interacting O…H atoms. Consequently, the exchange interaction refers to a chemical bond, namely the H-bond between two atoms, unlike BCP, which is not suitable for its detection. Full article
14 pages, 1054 KiB  
Review
Environmental Studies Based on Lake Sediment Records in China: A Review
by Minqiao Li, Guoping Tang and Huasheng Huang
Land 2024, 13(5), 637; https://doi.org/10.3390/land13050637 (registering DOI) - 08 May 2024
Abstract
Lake sediment records are of great importance for understanding the evolution of watershed environments. Various studies have been carried out to determine the depositional ages of lake sediments and to examine their physical, chemical, and biological characteristics. The aim is to construct the [...] Read more.
Lake sediment records are of great importance for understanding the evolution of watershed environments. Various studies have been carried out to determine the depositional ages of lake sediments and to examine their physical, chemical, and biological characteristics. The aim is to construct the historical vegetation, environment, and climate patterns in Chinese lake watersheds. In this review, we obtained relevant studies on lake sediment records by searching the key word ‘age-depth’ from the following databases: Web of Science and the China National Knowledge Infrastructure (CNKI, the largest Chinese academic database). We analyzed the literature based on its type (published in a Chinese/English journal or as a Master’s/PhD thesis), period of publication, journal (if published in a journal), key authors, study area, dating scale, and main aims. The results suggest that the lakes in the plateau regions are the most popular research topic, typically covering 100–200 years (short-term) and 500–30,000 years (long-term). The literature focuses on a wide range of topics, from past environmental evolution in watersheds to lake ecology, and it provides a solid foundation for a better understanding of the regional climate change and the preservation of lake environments and ecosystems. In the future, the resulting data obtained from environmental reconstructions with lake sediments will need to be integrated with emerging information processing technologies (e.g., artificial intelligence and meta-analysis) to disentangle the complex interplay between the Earth’s surface processes and global climate change; furthermore, strengthening interdisciplinary collaboration will deepen our comprehension of the man-land relationship and promote the sustainable management of lake ecosystems in the context of global climate change. Full article
(This article belongs to the Special Issue Dynamics of Terrestrial Environmental Systems)
21 pages, 1522 KiB  
Article
Novel Feature-Based Difficulty Prediction Method for Mathematics Items Using XGBoost-Based SHAP Model
by Xifan Yi, Jianing Sun and Xiaopeng Wu
Mathematics 2024, 12(10), 1455; https://doi.org/10.3390/math12101455 (registering DOI) - 08 May 2024
Abstract
The level of difficulty of mathematical test items is a critical aspect for evaluating test quality and educational outcomes. Accurately predicting item difficulty during test creation is thus significantly important for producing effective test papers. This study used more than ten years of [...] Read more.
The level of difficulty of mathematical test items is a critical aspect for evaluating test quality and educational outcomes. Accurately predicting item difficulty during test creation is thus significantly important for producing effective test papers. This study used more than ten years of content and score data from China’s Henan Provincial College Entrance Examination in Mathematics as an evaluation criterion for test difficulty, and all data were obtained from the Henan Provincial Department of Education. Based on the framework established by the National Center for Education Statistics (NCES) for test item assessment methodology, this paper proposes a new framework containing eight features considering the uniqueness of mathematics. Next, this paper proposes an XGBoost-based SHAP model for analyzing the difficulty of mathematics tests. By coupling the XGBoost method with the SHAP method, the model not only evaluates the difficulty of mathematics tests but also analyzes the contribution of specific features to item difficulty, thereby increasing transparency and mitigating the “black box” nature of machine learning models. The model has a high prediction accuracy of 0.99 for the training set and 0.806 for the test set. With the model, we found that parameter-level features and reasoning-level features are significant factors influencing the difficulty of subjective items in the exam. In addition, we divided senior secondary mathematics knowledge into nine units based on Chinese curriculum standards and found significant differences in the distribution of the eight features across these different knowledge units, which can help teachers place different emphasis on different units during the teaching process. In summary, our proposed approach significantly improves the accuracy of item difficulty prediction, which is crucial for intelligent educational applications such as knowledge tracking, automatic test item generation, and intelligent paper generation. These results provide tools that are better aligned with and responsive to students’ learning needs, thus effectively informing educational practice. Full article
12 pages, 750 KiB  
Article
Engineering, Emulators, Digital Twins, and Performance Engineering
by Ron S. Kenett
Electronics 2024, 13(10), 1829; https://doi.org/10.3390/electronics13101829 (registering DOI) - 08 May 2024
Abstract
Developments in digital twins are driven by the availability of sensor technologies, big data, first principles knowledge, and advanced analytics. In this paper, we discuss these changes at a conceptual level, presenting a shift from nominal engineering, aiming at design optimisation, to performance [...] Read more.
Developments in digital twins are driven by the availability of sensor technologies, big data, first principles knowledge, and advanced analytics. In this paper, we discuss these changes at a conceptual level, presenting a shift from nominal engineering, aiming at design optimisation, to performance engineering, aiming at adaptable monitoring diagnostic, prognostic, and prescriptive capabilities. A key element introduced here is the role of emulators in this transformation. Emulators, also called surrogate models or metamodels, provide monitoring and diagnostic capabilities. In particular, we focus on an optimisation goal combining optimised and robust performance derived from stochastic emulators. We demonstrate the methodology using two open-source examples and show how emulators can be used to complement finite element and computational fluid dynamic models in digital twin frameworks. The case studies consist of a mechanical system and a biological production process. Full article
(This article belongs to the Special Issue Digital Twins in Industry 4.0)
9 pages, 912 KiB  
Article
The Promising Effects of Erdosteine and Vitamin B in the Liver Ischemia/Reperfusion Model in Anesthetized Rats
by Elif Eygi, Rauf Gul, Murat Aslan, Zeynel Abidin Tas and Recep Dokuyucu
Medicina 2024, 60(5), 783; https://doi.org/10.3390/medicina60050783 (registering DOI) - 08 May 2024
Abstract
Background and Objectives: Erdosteine (Erd) is an antioxidant and anti-inflammatory drug. Vitamin B has been reported to exert anti-inflammatory and antioxidant effects. In this study, we investigated the effect of erdosteine and vitamin B complex on a liver ischemia/reperfusion (I/R) model. Materials and Methods: [...] Read more.
Background and Objectives: Erdosteine (Erd) is an antioxidant and anti-inflammatory drug. Vitamin B has been reported to exert anti-inflammatory and antioxidant effects. In this study, we investigated the effect of erdosteine and vitamin B complex on a liver ischemia/reperfusion (I/R) model. Materials and Methods: Thirty-two Wistar Albino male rats weighing 350–400 g were used. The animals were randomly selected and divided into four groups. The groups are as follows: first group (Sham), second group (I/R), third group (I/R + vit B), and fourth group (I/R + vit B + Erd). Rats were subjected to 45 min of hepatic ischemia, followed by a 45 min reperfusion period in the I/R and Vitamin B + Erd groups. An amount of 150 mg/kg/day of erdosteine was given orally for 2 days, and 0.05 mL/kg of i.p. vitamin B complex was given 30 min before the reperfusion. Serum biochemical parameters were measured. Serum Total Antioxidant Status (TAS) and Total Oxidant Status (TOS) were measured, and the Oxidative Stress Index (OSI) was calculated. Hepatic tissue samples were taken for the evaluation of histopathological features. Results: In terms of all histopathological parameters, there were significant differences in the I/R + vit B group and I/R + vit B + Erd group compared with the I/R group (p < 0.01). In terms of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), TNF-alpha, and IL-6 levels, there were significant differences between the I/R group and treatment groups (p < 0.01). The lowest TOS and OSI levels were obtained in the treatment groups, and these groups had statistically significantly higher TAS levels compared with the sham and I/R groups (p < 0.01). Conclusions: As a preliminary experimental study, our study suggests that these agents may have potential diagnostic and therapeutic implications for both ischemic conditions and liver-related diseases. These results suggest that the combination of vit B + Erd may be used to protect against the devastating effects of I/R injury. Our study needs to be confirmed by clinical studies with large participation. Full article
(This article belongs to the Special Issue Clinical Treatment and Innovation of Gastroenterology)
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18 pages, 1088 KiB  
Article
Utilization of Silica Filler as Reinforcement Material of Polylactic Acid (PLA) in 3D Printing Applications: Thermal, Rheological, and Mechanical Performance
by Vasileios Stratiotou Efstratiadis, Apostolos Argyros, Pavlos Efthymiopoulos, Georgios Maliaris, Nektarios K. Nasikas and Nikolaos Michailidis
Polymers 2024, 16(10), 1326; https://doi.org/10.3390/polym16101326 (registering DOI) - 08 May 2024
Abstract
Glass was introduced as an additive to filaments used for the manufacturing of composite materials, employed by Additive Manufacturing applications. Glass accounts for a large waste electric and electronic equipment (WEEE) percentage, and its recovery and recycling can lead to the production of [...] Read more.
Glass was introduced as an additive to filaments used for the manufacturing of composite materials, employed by Additive Manufacturing applications. Glass accounts for a large waste electric and electronic equipment (WEEE) percentage, and its recovery and recycling can lead to the production of sustainable composite materials. In this work, poly(lactic acid) (PLA)/commercially available silicon oxide composite filaments were manufactured and their structural, thermal, rheological, and mechanical properties were assessed. Scanning Electron Microscopy confirmed the 1:2 ratio of silicon: oxygen, along with the relatively low adhesion between the filler and the matrix. Differential Scanning Calorimetry presented steady glass transition and melting temperatures of composites, whereas a crystallization temperature of 10% wt. and a crystallinity of 15% wt. composite slightly increased. Rheological analysis showcased that the viscosity of the composite filaments decreased compared to PLA (10–100 compared to 300–400 Pa·s), with a more shear-thinning behavior. Dynamic mechanical analysis exhibited increased elastic, flexural moduli, and flexural strength of composites (up to 16, 23, and 11%, respectively), whereas tensile strength and elongation decreased. The affordability of raw materials (with the future introduction of recycled ones) and the minimal processing steps can lead to the potential scaling up of the study. Full article
(This article belongs to the Special Issue Advancements in Rheology and Processing of Polymer Materials)
16 pages, 3148 KiB  
Article
Real-Time Estimation of BDS-3 Satellite Clock Offset with Ambiguity Resolution Using B1C/B2a Signals
by Wei Xie, Kan Wang, Wenju Fu, Shichao Xie, Bobin Cui and Mengyuan Li
Remote Sens. 2024, 16(10), 1666; https://doi.org/10.3390/rs16101666 (registering DOI) - 08 May 2024
Abstract
The third generation of the BeiDou navigation satellite system (BDS-3) can transmit five-frequency signals. The real-time satellite clock offset of BDS-3 is typically generated utilizing the B1I/B3I combination with the ambiguity-float solutions. By conducting the ambiguity resolution (AR), the reliability of the satellite [...] Read more.
The third generation of the BeiDou navigation satellite system (BDS-3) can transmit five-frequency signals. The real-time satellite clock offset of BDS-3 is typically generated utilizing the B1I/B3I combination with the ambiguity-float solutions. By conducting the ambiguity resolution (AR), the reliability of the satellite clock offset can be improved. However, the performance of BDS-3 ambiguity-fixed real-time satellite clock offset with B1C/B2a signals remains unknown and unrevealed. In this contribution, the performance of the BDS-3 ambiguity-fixed satellite clock offset with the new B1C/B2a signals is investigated. One week of observation data from 85 stations was used to perform ambiguity-fixed satellite clock offset estimation. For B1I/B3I and B1C/B2a signals, the wide-lane (WL) uncalibrated phase delay (UPD) on the satellite end is fairly stable for one day, while the narrow-lane (NL) UPD standard deviation (STD) amounts to 0.122 and 0.081 cycles, respectively. The mean ambiguity fixing rate is 80.7% and 78.0% for these two signal combinations, and the time to first fix (TTFF) for the B1C/B2a signals is remarkably shorter than that of the B1I/B3I signals. The STDs of the ambiguity-float and -fixed satellite clock offsets are 0.033 and 0.026 ns, respectively, for the B1I/B3I combination, and it is reduced to 0.024 and 0.023 ns for B1C/B2a signals, respectively. Using the estimated UPD and clock offset products, the positioning performance of the kinematic Precise Point Positioning (PPP)-AR results amounts to 1.56, 1.23, and 4.46 cm in the east, north, and up directions for B1I/B3I signals, respectively. It is improved to 1.36, 1.16, and 4.25 cm using the products estimated with the B1C/B2a signals, with improvements of 12.8%, 5.7%, and 4.7% in three directions, respectively. The experiments showed that the performances of the ambiguity-fixed satellite clock offsets and the PPP-AR results using B1C/B2a signals are better than those of B1I/B3I. Full article
22 pages, 1538 KiB  
Article
Comparing Bio-Ester and Mineral-Oil Emulsions on Tool Wear and Surface Integrity in Finish Turning a Ni-Based Superalloy
by Paul Wood, Fathi Boud, Andrew Mantle, Wayne Carter, Syed Hossain, Urvashi Gunputh, Marzena Pawlik, Yiling Lu, José Díaz-Álvarez and María Henar Miguélez
Lubricants 2024, 12(5), 164; https://doi.org/10.3390/lubricants12050164 (registering DOI) - 08 May 2024
Abstract
The paper compares the performance of two bio-ester and two mineral-oil emulsion metalworking fluids (MWFs) in finish turning an Inconel 718 alloy bar with a high hardness (HB 397–418). In this study, a coolant with a lean concentrate diluted at 6.5% to create [...] Read more.
The paper compares the performance of two bio-ester and two mineral-oil emulsion metalworking fluids (MWFs) in finish turning an Inconel 718 alloy bar with a high hardness (HB 397–418). In this study, a coolant with a lean concentrate diluted at 6.5% to create an emulsion with stabilised water hardness was used to prepare each MWF. The finish-turning method used a small tool nose radius (0.4 mm) and small depth of cut (0.25 mm) to turn down 52.5-mm diameter bars in multiple passes to reach a maximum tool flank wear of 200 µm. In each MWF turning test, the tool flank wear, cutting forces, and surface roughness were measured against cut time. Chips from each MWF turning test were also collected at the same cut time instances. The surface and subsurface integrity on a workpiece obtained from each MWF turning test were compared by using a new unworn tool. Overall, for the machining parameters studied, the findings suggest the bio-esters were capable of equivalent machining performance as the mineral-oil emulsions, apart from one bio-ester that displayed improved surface roughness. Common to all MWF turning tests was a change in the chip form at low flank wear, which is discussed. Further findings discussed include the sensitivity of the concentration of the MWF diluted in the emulsion and the effect of the workpiece hardness within the batch used, with useful recommendations to improve the finish-turning method for the assessment of MWFs. Full article
(This article belongs to the Special Issue Friction and Wear of Alloys)
14 pages, 2577 KiB  
Article
A Low-Frequency Fiber Bragg Grating Acceleration Sensor Based on Spring Support and Symmetric Compensation Structure with Flexible Hinges
by Lijun Meng, Panpan Zhu, Xin Tan and Xiao Huang
Sensors 2024, 24(10), 2990; https://doi.org/10.3390/s24102990 (registering DOI) - 08 May 2024
Abstract
To measure vibration signals, a low-frequency fiber Bragg grating (FBG) acceleration sensor featuring a flexible hinge with a spring support and symmetric compensation structure has been designed. Based on the mechanical model of the sensor’s structure, the expressions for sensitivity and resonant frequency [...] Read more.
To measure vibration signals, a low-frequency fiber Bragg grating (FBG) acceleration sensor featuring a flexible hinge with a spring support and symmetric compensation structure has been designed. Based on the mechanical model of the sensor’s structure, the expressions for sensitivity and resonant frequency of the sensor are derived. The structural parameters of the sensor are optimized, and a simulation analysis is conducted using ANSYS 19.2 software. According to the results of simulation analysis and size optimization, the sensor prototype is constructed. Subsequently, its amplitude-frequency response, sensitivity, and temperature characteristics are investigated through vibration experiments. The experimental results show that the resonant frequency of the sensor is 73 Hz, the operating frequency range is 0~60 Hz, and the sensitivity measures 24.24 pm/g. This design meets the requirements for measuring vibration signals at low frequencies. Full article
(This article belongs to the Special Issue Emerging Sensing Technologies for Machine Health State Awareness)
18 pages, 6658 KiB  
Article
Comparison of Fracture Behavior in Single-Edge Notched Beams Reinforced with Steel Bars or CFRP Bars
by Zhiyong Wang, Yushu Yang, Min Song, Jie Zhang and Zhihua Wang
Materials 2024, 17(10), 2216; https://doi.org/10.3390/ma17102216 (registering DOI) - 08 May 2024
Abstract
To explore and compare the failure modes, deformation behaviors, and load-bearing capacities of single-edge notched (SEN) beams strengthened with carbon fiber-reinforced polymer (CFRP) and steel bars, static and dynamic three-point bending tests on both types of concrete beams have been carried out in [...] Read more.
To explore and compare the failure modes, deformation behaviors, and load-bearing capacities of single-edge notched (SEN) beams strengthened with carbon fiber-reinforced polymer (CFRP) and steel bars, static and dynamic three-point bending tests on both types of concrete beams have been carried out in this study. During the static tests, the electro-hydraulic servo machine served as a loading device to apply pressure to CFRP beams and reinforced concrete (RC) beams. During the impact experiments, different impact velocities were imparted by adjusting the drop hammer’s height. Thus, information regarding crack propagation, energy absorption, and deformation was obtained. The results from the static tests showed that the RC beams predominantly experienced shear failure. In contrast, the CFRP beams primarily exhibited bending–shear failure, attributed to the relatively weaker bond strength between the bars and the concrete. Impact tests were conducted at three different velocities in this study. As the impact velocity increased, both types of concrete beams transitioned from bending failure to bending–shear failure. At the lowest velocity, the difference in energy absorption between beams reinforced with different materials was insignificant during the bending process. However, at the highest velocity, CFRP beams absorbed less energy than RC beams. The study of structures’ impact failure modes and their mechanical characteristics offers valuable references for the anti-collision design and protection of structures. Full article
27 pages, 722 KiB  
Article
Action-Based Fiscal Consolidations and Economic Growth
by Markus Brueckner
J. Risk Financial Manag. 2024, 17(5), 194; https://doi.org/10.3390/jrfm17050194 (registering DOI) - 08 May 2024
Abstract
This paper tests the hypothesis that action-based fiscal consolidations have a negative effect on GDP growth. Using the IMF’s dataset on action-based fiscal consolidations, instrumental variables’ regressions show that action-based fiscal consolidations have a significant positive effect on GDP growth. The instrumental variables’ [...] Read more.
This paper tests the hypothesis that action-based fiscal consolidations have a negative effect on GDP growth. Using the IMF’s dataset on action-based fiscal consolidations, instrumental variables’ regressions show that action-based fiscal consolidations have a significant positive effect on GDP growth. The instrumental variables’ regressions also show that action-based fiscal consolidations significantly increase investment and productivity. The findings presented in this paper thus strongly reject the hypothesis that action-based fiscal consolidations reduce growth. The paper argues that least squares estimates presented in previous literature suffer from negative reverse causality bias: GDP growth has a significant positive effect on both the likelihood and the magnitude of action-based fiscal consolidations. To uncover causal effects of action-based fiscal consolidations, researchers need to use an instrumental variables approach. Full article
18 pages, 2108 KiB  
Article
Exploring the Causal Effects of Mineral Metabolism Disorders on Telomere and Mitochondrial DNA: A Bidirectional Two-Sample Mendelian Randomization Analysis
by Zhijun Feng, Yinghui Wang, Zhengzheng Fu, Jing Liao, Hui Liu and Meijuan Zhou
Nutrients 2024, 16(10), 1417; https://doi.org/10.3390/nu16101417 (registering DOI) - 08 May 2024
Abstract
The aim of this study was to assess the causal relationships between mineral metabolism disorders, representative of trace elements, and key aging biomarkers: telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN). Utilizing bidirectional Mendelian randomization (MR) analysis in combination with the two-stage [...] Read more.
The aim of this study was to assess the causal relationships between mineral metabolism disorders, representative of trace elements, and key aging biomarkers: telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN). Utilizing bidirectional Mendelian randomization (MR) analysis in combination with the two-stage least squares (2SLS) method, we explored the causal relationships between mineral metabolism disorders and these aging indicators. Sensitivity analysis can be used to determine the reliability and robustness of the research results. The results confirmed that a positive causal relationship was observed between mineral metabolism disorders and TL (p < 0.05), while the causal relationship with mtDNA-CN was not significant (p > 0.05). Focusing on subgroup analyses of specific minerals, our findings indicated a distinct positive causal relationship between iron metabolism disorders and both TL and mtDNA-CN (p < 0.05). In contrast, disorders in magnesium and phosphorus metabolism did not exhibit significant causal effects on either aging biomarker (p > 0.05). Moreover, reverse MR analysis did not reveal any significant causal effects of TL and mtDNA-CN on mineral metabolism disorders (p > 0.05). The combination of 2SLS with MR analysis further reinforced the positive causal relationship between iron levels and both TL and mtDNA-CN (p < 0.05). Notably, the sensitivity analysis did not indicate significant pleiotropy or heterogeneity within these causal relationships (p > 0.05). These findings highlight the pivotal role of iron metabolism in cellular aging, particularly in regulating TL and sustaining mtDNA-CN, offering new insights into how mineral metabolism disorders influence aging biomarkers. Our research underscores the importance of trace element balance, especially regarding iron intake, in combating the aging process. This provides a potential strategy for slowing aging through the adjustment of trace element intake, laying the groundwork for future research into the relationship between trace elements and healthy aging. Full article
(This article belongs to the Special Issue New Insights in Molecular Mechanism of Micronutrients Metabolism)
15 pages, 10525 KiB  
Article
Waveform Complexity and Positioning Analysis of Acoustic Emission Events during the Compression Failure Process of a Rock Burst Prone Sample
by Wenlong Zhang, Jiajia Yu, Xiufeng Xu, Jianju Ren, Kaide Liu and Huifang Shi
Buildings 2024, 14(5), 1331; https://doi.org/10.3390/buildings14051331 (registering DOI) - 08 May 2024
Abstract
The localization results of acoustic emission (AE) events can reflect the location and pattern of burst-prone rock failures. However, event localization heavily depends on the quality of the original waveform of the sensor. Therefore, this study analyzed the AE waveform of a rock [...] Read more.
The localization results of acoustic emission (AE) events can reflect the location and pattern of burst-prone rock failures. However, event localization heavily depends on the quality of the original waveform of the sensor. Therefore, this study analyzed the AE waveform of a rock sample under compression to evaluate its failure localization and quality. From the research results, it could be seen that the initial failure was relatively calm, with clear take-off points, which can be better used for accurate AE event positioning. However, the later failure was severe, causing the take-off points of most sensors to be very unclear, and positioning methods that rely on take-off points cannot be used for positioning, let alone simply using the positioning results of the built-in software. This research result reminds researchers who use AE signals for event localization to first examine the quality and status of the original waveform, providing a basis for obtaining accurate localization results, in order to further accurately study the subsequent failure patterns. The above facts indicate that the initial failure is small and scattered, while the later failure is large and concentrated, with certain fractal characteristics. Full article
(This article belongs to the Special Issue Buildings and Infrastructures under Natural Hazards)
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15 pages, 1453 KiB  
Article
Cumin Seed Oil Induces Oxidative Stress-Based Antifungal Activities on Fusarium graminearum
by Emre Yörük, Zeynep Danışman, Murat Pekmez and Tapani Yli-Mattila
Pathogens 2024, 13(5), 395; https://doi.org/10.3390/pathogens13050395 (registering DOI) - 08 May 2024
Abstract
In this study, the antifungal activity of cumin seed oil (CSO) was tested on Fusarium graminearum. (i) Minimum inhibitory concentrations (MICs) and related concentrations (IC75, IC50, and IC25) were detected; (ii) toxicity was evaluated by a [...] Read more.
In this study, the antifungal activity of cumin seed oil (CSO) was tested on Fusarium graminearum. (i) Minimum inhibitory concentrations (MICs) and related concentrations (IC75, IC50, and IC25) were detected; (ii) toxicity was evaluated by a water-soluble tetrazolium salt-1 (WST-1) assay; (iii) genomic/epigenomic alterations were evaluated by the coupled restriction enzyme digestion-random amplification (CRED-RA) method; (iv) oxidative stress was investigated by CAT expression, catalase activity, and DCF-DA staining; (v) deoxynivalenol biosynthesis was evaluated by tri6 expression; (vi) and potential effects of CSO on wheat were tested by a water loss rate (WLR) assay. MIC, IC75, IC50 and IC25 values were detected at 0.5, 0.375, 0.25, and 0.125 mg mL−1. In WST-1 assays, significant decreases (p < 0.001) were detected. Genomic template stability (GTS) related to methylation differences ranged from 94.60% to 96.30%. Percentage polymorphism for HapII/MspI values were as 9.1%/15.8%. CAT (oxidative stress-related catalase) and tri6 (zinc finger motif transcription factor) gene expressions were recorded between 5.29 ± 0.74 and 0.46 ± 0.10 (p < 0.05). Increased catalase activity was detected (p < 0.05) by spectrophotometric assays. DCF-DA-stained (oxidative stressed) cells were increased in response to increased concentrations, and there were no significant changes in WLR values. It was concluded that CSO showed strong antifungal activity on F. graminearum via different physiological levels. Full article
(This article belongs to the Special Issue Current Research on Host–Pathogen Interaction in 2024)
12 pages, 1136 KiB  
Article
Genetic Screening Revealed the Negative Regulation of miR-310~313 Cluster Members on Imd Pathway during Gram-Negative Bacterial Infection in Drosophila
by Yao Li, Yixuan Sun, Ruimin Li, Hongjian Zhou, Shengjie Li and Ping Jin
Genes 2024, 15(5), 601; https://doi.org/10.3390/genes15050601 (registering DOI) - 08 May 2024
Abstract
Innate immune response is the first line of host defense against pathogenic microorganisms, and its excessive or insufficient activation is detrimental to the organism. Many individual microRNAs (miRNAs) have emerged as crucial post-transcriptional regulators of immune homeostasis in Drosophila melanogaster. However, the [...] Read more.
Innate immune response is the first line of host defense against pathogenic microorganisms, and its excessive or insufficient activation is detrimental to the organism. Many individual microRNAs (miRNAs) have emerged as crucial post-transcriptional regulators of immune homeostasis in Drosophila melanogaster. However, the synergistical regulation of miRNAs located within a cluster on the Imd-immune pathway remains obscured. In our study, a genetic screening with 52 transgenic UAS-miRNAs was performed to identify ten miRNAs or miRNA clusters, including the miR310~313 cluster, which may function on Imd-dependent immune responses. The miRNA RT-qPCR analysis showed that the expression of miR-310~313 cluster members exhibited an increase at 6–12 h post E. Coli infection. Furthermore, the overexpression of the miR-310~313 cluster impaired the Drosophila survival. And the overexpression of miR-310/311/312 reduced Dpt expression, an indication of Imd pathway induced by Gram-negative bacteria. Conversely, the knockdown of miR-310/311/312 led to increases in Dpt expression. The Luciferase reporter expression assays and RT-qPCR analysis confirmed that miR-310~313 cluster members directly co-targeted and inhibited Imd transcription. These findings reveal that the members of the miR-310~313 cluster synergistically inhibit Imd-dependent immune responses by co-targeting the Imd gene in Drosophila. Full article
9 pages, 465 KiB  
Article
Role of Lipoprotein Ratios and Remnant Cholesterol in Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA)
by Vincenzo Sucato, Luca Di Fazio, Cristina Madaudo, Giuseppe Vadalà, Alessandro D’Agostino, Salvatore Evola, Giuseppina Novo, Egle Corrado and Alfredo Ruggero Galassi
J. Cardiovasc. Dev. Dis. 2024, 11(5), 146; https://doi.org/10.3390/jcdd11050146 (registering DOI) - 08 May 2024
Abstract
Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical situation characterized by evidence of acute myocardial infarction (AMI)—according to the Fourth Universal Definition of Myocardial Infarction—with normal or near-normal coronary arteries on angiographic study (stenosis < 50%). This condition is extremely [...] Read more.
Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical situation characterized by evidence of acute myocardial infarction (AMI)—according to the Fourth Universal Definition of Myocardial Infarction—with normal or near-normal coronary arteries on angiographic study (stenosis < 50%). This condition is extremely variable in etiology, pathogenic mechanisms, clinical manifestations, prognosis and consequently therapeutic approach. Objective: The objective of the study was the evaluation of remnant cholesterol (RC), monocyte/high-density lipoprotein cholesterol ratio (MHR), platelet/lymphocyte ratio (PLR) and various lipoprotein ratios in patients with MINOCA in order to establish their validity as predictors of this event. Materials and Methods: We included 114 patients hospitalized in the Intensive Coronary Care Unit (ICCU) and Hospital Wards of our Hospital Center from 2015 to 2019 who received a diagnosis of MINOCA compared to a control group of 110 patients without previous cardiovascular events. RC was calculated with the following formula: RC = total cholesterol (TC) − HDL-C − LDL-C. MHR was calculated by dividing the monocyte count in peripheral blood by high-density lipoprotein cholesterol (HDL-C) levels; PLR was obtained by dividing platelet count by lymphocyte count. We also calculated various lipoprotein ratios, like total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C), low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C), triglycerides/high-density lipoprotein cholesterol (TG/HDL-C), and non-high-density lipoprotein cholesterol/high-density lipoprotein cholesterol (non-HDL-C/HDL-C) ratios. Results: The MINOCA group had higher mean levels of RC (21.3 ± 10.6 vs. 13.2 ± 7.7 mg/dL), MHR (23 ± 0.009 vs. 18.5± 8.3) and PLR (179.8 ± 246.1 vs. 135 ± 64.7) than the control group. Only the mean values of all calculated lipoprotein ratios were lower in MINOCA patients. Statistical significance was achieved only in the RC evaluation. Conclusions: Higher levels of RC and MHR were found in patients with MINOCA. We also observed higher levels of PLR than in the control group. Only various lipoprotein ratios were lower, but this could reflect the extreme heterogeneity underlying the pathogenic mechanisms of MINOCA. In patients who receive a diagnosis of MINOCA with a baseline alteration of the lipid profile and higher levels of cholesterol at admission as well, the evaluation of these parameters could play an important role, providing more detailed information about their cardiometabolic risk. Full article
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14 pages, 1677 KiB  
Article
Bt-Modified Transgenic Rice May Shift the Composition and Diversity of Rhizosphere Microbiota
by Qixing Huang, Yuliang Zhang, Yanhua Tan, Hua Kong, Yang Cao, Jungang Wang, Guohua Yin and Anping Guo
Plants 2024, 13(10), 1300; https://doi.org/10.3390/plants13101300 (registering DOI) - 08 May 2024
Abstract
Plants significantly shape root-associated microbiota, making rhizosphere microbes useful environmental indicator organisms for safety assessment. Here, we report the pyrosequencing of the bacterial 16S ribosomal RNA in rhizosphere soil samples collected from transgenic cry1Ab/cry1Ac Bt rice Huahui No. 1 (GM crop) and its [...] Read more.
Plants significantly shape root-associated microbiota, making rhizosphere microbes useful environmental indicator organisms for safety assessment. Here, we report the pyrosequencing of the bacterial 16S ribosomal RNA in rhizosphere soil samples collected from transgenic cry1Ab/cry1Ac Bt rice Huahui No. 1 (GM crop) and its parental counterpart, Minghui63. We identified a total of 2579 quantifiable bacterial operational taxonomic units (OTUs). Many treatment-enriched microbial OTUs were identified, including 14 NonGM-enriched OTUs and 10 GM-enriched OTUs. OTUs belonging to the phyla Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes, Nitrospirae, Chlorobi and GN04 were identified as statistically different in abundance between GM and the other two treatments. Compared with the different impacts of different rice varieties on microbiota, the impact of rice planting on microbiota is more obvious. Furthermore, Huahui No. 1 transgenic Bt rice had a greater impact on the rhizosphere bacterial communities than Minghui63. Early developmental stages of the transgenic Bt rice had a significant impact on many Bacillaceae communities. Soil chemical properties were not significantly altered by the presence of transgenic Bt rice. The peak concentration level of Bt protein products was detected during the seedling stage of transgenic Bt rice, which may be an intriguing factor for bacterial diversity variations. Based on these findings, we conclude that transgenic Bt rice has a significant impact on root-associated bacteria. This information may be leveraged in future environmental safety assessments of transgenic Bt rice varieties. Full article
(This article belongs to the Special Issue Detoxification and Control of Mycotoxins in Plants)
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22 pages, 1076 KiB  
Article
Dynamic Changes in Ecosystem Service Value and Ecological Compensation in Original Continuous Poverty-Stricken Areas of China
by Zhe Yu, Chunwei Song and Huishi Du
Sustainability 2024, 16(10), 3947; https://doi.org/10.3390/su16103947 (registering DOI) - 08 May 2024
Abstract
The original contiguous poverty-stricken areas of China (OCPSAC) are a regional complex with natural and human attributes. Their ecosystem services are highly complex in their contribution to human well-being. The region’s ecosystem is unstable and socio-economic development is unbalanced, making it a key [...] Read more.
The original contiguous poverty-stricken areas of China (OCPSAC) are a regional complex with natural and human attributes. Their ecosystem services are highly complex in their contribution to human well-being. The region’s ecosystem is unstable and socio-economic development is unbalanced, making it a key area for research and the implementation of the United Nations Sustainable Development Goals. Therefore, it has become the focus of social attention. This study obtained satellite remote sensing images of the Landsat8 based on the Google Earth Engine. The dynamic characteristics of the spatial and temporal distribution of the OCPSAC’s land use changes in 2015 and 2022 were analyzed. The characteristics of the changes in ecosystem service value (ESV) were quantitatively evaluated through the revised ESV equivalent scale, and the ecological compensation (EC) standards and EC priority level suitable for the region were explored. The research results showed that: (1) the OCPSAC land use types were mainly grassland, forests, and deserts, accounting for more than 80% of the research area; (2) the OCPSAC’s ESV reached CNY 115.578 billion, and the Tibet Region (TR) and Tibetan Region of Four Provinces (TRFP) had the highest ESVs, accounting for 32.28% and 19.64%, respectively. Among individual ESVs, hydrological regulation (HR) and climate regulation (CR) had the highest values, accounting for 55.23% of the research area; (3) the ESV of the research area presented the characteristics of being high in the middle and low at both ends. From the terrain perspective, the areas with a higher ESV per unit area were distributed in the second altitude gradient, followed by China’s third altitude gradient, and the first altitude gradient was the lowest; (4) in the period of 2015–2022, the ESV increased by CNY 21.39 billion, of which TR’s ESV increased by CNY 17.44 billion. From the perspective of a single ESV, the value of waste treatment (WT), HR, nutrient cycle (NC), and provide aesthetic landscape (PAL) increased by CNY 24.38 billion; and (5) in 2022, the EC standard of the OCPSAC was CNY 917.14 billion. High-EC-value areas were mainly distributed in TR and TRFP, accounting for 72.79% of the total compensation amount, of which only TR’s EC amount exceeded a GDP of 2022, accounting for 4.77% of the total compensation. The purpose of this study was to provide a reference for ecosystem sustainability and EC. Full article
11 pages, 567 KiB  
Article
Alexithymia Increases Pericranial and Cervical Muscle Tenderness in Women with Migraine
by Eugenia Rota, Elisa Cavagnetto, Paolo Immovilli, Enrico Frola, Pavel Salari, Nicola Morelli and Alessandro Battaggia
J. Clin. Med. 2024, 13(10), 2772; https://doi.org/10.3390/jcm13102772 (registering DOI) - 08 May 2024
Abstract
Background/Objectives: Alexithymia is characterized by a deficit in identifying and communicating feelings. Emerging evidence suggests that alexithymia is highly prevalent in migraine, in a complex interplay with psychiatric comorbidity. Pericranial/cervical muscle tenderness is a remarkable clinical feature in a large proportion of migraine [...] Read more.
Background/Objectives: Alexithymia is characterized by a deficit in identifying and communicating feelings. Emerging evidence suggests that alexithymia is highly prevalent in migraine, in a complex interplay with psychiatric comorbidity. Pericranial/cervical muscle tenderness is a remarkable clinical feature in a large proportion of migraine patients. This pilot study aimed at investigating the relationship between alexithymia and pericranial/cervical muscle tenderness in female migraineurs. Methods: A total of 42 female patients fulfilling the diagnostic criteria for migraine were enrolled into this pilot, observational, cross-sectional study after informed consent was obtained. Each patient underwent a psychological assessment to identify any alexithymia by means of TAS-20, anxiety/mood comorbidity (by means of STAI-Y1 STAI-Y2, BDI-II), and migraine-related disability (by means of HIT-6), and a physical cranial/cervical musculoskeletal examination. Palpation of pericranial and cervical muscles was carried out in the standardized manner. A Cumulative Muscle Tenderness (CUM) score (0–6) was calculated for each patient. A multivariate analysis was performed to investigate any association amongst the TAS-20 score, the CUM score, and the following covariates: BDI-II, STAI-Y1, STAI-Y2, and HIT-6 scores, age, disease duration, monthly migraine days, and average head pain intensity in the previous three months. Results: Overall, 35.6% of the sample had alexithymia. The multivariate analysis detected a linear and independent relationship between the TAS-20 and CUM scores, with a statistically significant (p = 0.017) association. Conclusions: This pilot study suggests that alexithymia plays a role in increasing pericranial/cervical muscle tenderness in migraine, independently from psychiatric comorbidity. A novel therapeutical approach, targeting alexithymia, may well reduce muscular tenderness in female migraineurs. Full article
(This article belongs to the Special Issue Recent Progress in Multiple Sclerosis and Migraine)

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