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17 pages, 1571 KiB  
Systematic Review
Vertical Control in Molar Distalization by Clear Aligners: A Systematic Review and Meta-Analysis
by Tiffany H. Park, Christie Shen, Chun-Hsi Chung and Chenshuang Li
J. Clin. Med. 2024, 13(10), 2845; https://doi.org/10.3390/jcm13102845 (registering DOI) - 11 May 2024
Abstract
Background: Molar distalization is used to correct molar relationships or to create space for mild anterior crowding. However, whether clear aligners can provide proper vertical control with the sequential distalization strategy has been highly debated. Thus, the current study aimed to systematically review [...] Read more.
Background: Molar distalization is used to correct molar relationships or to create space for mild anterior crowding. However, whether clear aligners can provide proper vertical control with the sequential distalization strategy has been highly debated. Thus, the current study aimed to systematically review the amount of dentoskeletal changes in the vertical dimension that results from sequential molar distalization in clear aligner therapy without temporary anchorage devices (TADs). Methods: Registered with PROSPERO (CRD42023447211), relevant original studies were screened from seven databases and supplemented by a manual search by two investigators independently. Articles were screened against inclusion and exclusion criteria, and a risk of bias assessment was conducted for each included article. Relevant data were extracted from the included articles and meta-analysis was performed using RStudio. Results: Eleven articles (nine for maxillary distalization and two for mandibular distalization) were selected for the final review. All studies have a high or medium risk of bias. For maxillary molar distalization, the meta-analysis revealed 0.26 mm [0.23 mm, 0.29 mm] of maxillary first molar intrusion based on post-distalization dental model analysis, as well as 0.50 mm [−0.78 mm, 1.78 mm] of maxillary first molar intrusion and 0.60 mm [−0.42 mm, 1.62 mm] of maxillary second molar intrusion based on post-treatment lateral cephalometric analysis. Skeletally, there was a −0.33° [−0.67°, 0.02°] change in the SN-GoGn angle, −0.23° [−0.30°, 0.75°] change in the SN-MP angle, and 0.09° [−0.83°, 1.01°] change in the PP-GoGn angle based on post-treatment lateral cephalometric analysis. There was insufficient data for meta-analysis for mandibular molar distalization. Conclusions: No significant changes in vertical dimension were observed, both dentally and skeletally, after maxillary molar distalization with a sequential distalization strategy. However, further studies on this topic are needed due to the high risk of bias in the currently available studies. Full article
(This article belongs to the Special Issue New Approaches and Technologies in Orthodontics—2nd Edition)
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24 pages, 8084 KiB  
Article
An Electronic Structure Investigation of PEDOT with AlCl4− Anions—A Promising Redox Combination for Energy Storage Applications
by Ben Craig, Peter Townsend, Carlos Ponce de Leon, Chris-Kriton Skylaris and Denis Kramer
Polymers 2024, 16(10), 1376; https://doi.org/10.3390/polym16101376 (registering DOI) - 11 May 2024
Abstract
In this work, we use density functional theory to investigate the electronic structure of poly(3,4-ethylenedioxythiophene) (PEDOT) oligomers with co-located AlCl4− anions, a promising combination for energy storage. The 1980s bipolaron model remains the dominant interpretation of the electronic structure of PEDOT [...] Read more.
In this work, we use density functional theory to investigate the electronic structure of poly(3,4-ethylenedioxythiophene) (PEDOT) oligomers with co-located AlCl4− anions, a promising combination for energy storage. The 1980s bipolaron model remains the dominant interpretation of the electronic structure of PEDOT despite recent theoretical progress that has provided new definitions of bipolarons and polarons. By considering the influence of oligomer length, oxidation or anion concentration and spin state, we find no evidence for many of the assertions of the 1980s bipolaron model and so further contribute to a new understanding. No self-localisation of positive charges in PEDOT is found, as predicted by the bipolaron model at the hybrid functional level. Instead, our results show distortions that exhibit a single or a double peak in bond length alternations and charge density. Either can occur at different oxidation or anion concentrations. Rather than representing bipolarons or polaron pairs in the original model, these are electron distributions driven by a range of factors. Distortions can span an arbitrary number of nearby anions. We also contribute a novel conductivity hypothesis. Conductivity in conducting polymers has been observed to reduce at anion concentrations above 0.5. We show that at high anion concentrations, the energy of the localised, non-bonding anionic orbitals approaches that of the system HOMO due to Coulombic repulsion between anions. We hypothesize that with nucleic motion in the macropolymer, these orbitals will interfere with the hopping of charge carriers between sites of similar energy, lowering conductivity. Full article
(This article belongs to the Special Issue Advanced Polymers for High-Performance Batteries)
16 pages, 1162 KiB  
Article
Self-Calibration Method for Circular Encoders Based on Inertia and a Single Read-Head
by Xiaoyi Wang, Longyuan Xiao, Kunlei Zheng, Chengxiang Zhao, Mingkang Liu, Tianyang Yao, Dongjie Zhu, Gaojie Liang and Zhaoyao Shi
Sensors 2024, 24(10), 3069; https://doi.org/10.3390/s24103069 (registering DOI) - 11 May 2024
Abstract
This article proposes a new self-calibration method for circular encoders based on inertia and a single read-head. The velocity curves of the circular encoder are fitted with polynomials and, based on the principle of circle closure and the periodicity of the distribution for [...] Read more.
This article proposes a new self-calibration method for circular encoders based on inertia and a single read-head. The velocity curves of the circular encoder are fitted with polynomials and, based on the principle of circle closure and the periodicity of the distribution for angle intervals, the proportionality between the theoretical value and the actual value of each angle interval is obtained. In the experimental system constructed, the feasibility of the proposed method was verified through self-calibration experiments, repeatability experiments, and comparative experiments with the time-measurement dynamic reversal (TDR) method. In addition, this article also proposes an iterative method to improve the self-calibration accuracy. Experimental verification was carried out, and the results show that the new method can effectively compensate for the error of angle measurement in the circular encoder. The peak-to-peak value of the error of angle measurement was reduced from 239.343” to 11.867”, and the repeatability of the calibration results of the new method was less than 2.77”. Full article
(This article belongs to the Section Optical Sensors)
12 pages, 1208 KiB  
Article
Evaluation of Mechanical Wood Properties of Silver Birch (Betula pendula L. Roth.) of Half-Sib Genetic Families
by Benas Šilinskas, Iveta Varnagirytė-Kabašinskienė, Lina Beniušienė, Marius Aleinikovas, Mindaugas Škėma and Virgilijus Baliuckas
Forests 2024, 15(5), 845; https://doi.org/10.3390/f15050845 (registering DOI) - 11 May 2024
Abstract
Silver birch, a widely distributed deciduous tree native to Europe, is valued for its wood applications in construction, furniture making, and paper production. In Lithuania, silver birch ranks as the third most common forest-tree species, comprising 22% of the forested areas, and is [...] Read more.
Silver birch, a widely distributed deciduous tree native to Europe, is valued for its wood applications in construction, furniture making, and paper production. In Lithuania, silver birch ranks as the third most common forest-tree species, comprising 22% of the forested areas, and is an important species for tree breeding due to its potential and adaptability. This study was focused on assessing the mechanical properties of wood (sample and log hardness, wood density, dynamic modulus of elasticity (MOEdyn), static modulus of elasticity (MOE) and bending strength (MOR)) in silver birch (Betula pendula L. Roth.) trees from different half-sibling families. Two experimental plantations of the progenies of Lithuanian populations (half-sib families) of silver birch from different regions were analysed. From these plantations, four genetic families were selected for mechanical properties evaluation. The study findings revealed significant variability in various wood properties among different genetic families, although the static modulus of elasticity did not exhibit significant differences between the chosen genetic families. All measured wood properties decreased from the bottom to the top of the model trees. Wood hardness displayed a moderately negative correlation for wood density and weak correlations for MOE and MOR. Given the weak correlations between wood hardness and other wood mechanical properties, it is suggested that MOEdyn would be a more suitable trait for genetic studies. Full article
(This article belongs to the Section Wood Science and Forest Products)
13 pages, 489 KiB  
Article
Impact of Replacement Therapy on Pregnancy Outcomes in Hemophilia Carriers: A Historical Cohort Study in Saudi Arabia
by Ebtisam Bakhsh
Life 2024, 14(5), 623; https://doi.org/10.3390/life14050623 (registering DOI) - 11 May 2024
Abstract
This retrospective cohort study evaluates the safety and efficacy of replacement therapy with regard to pregnancy outcomes in hemophilia carriers. Hemophilia carriers face elevated bleeding risks during pregnancy, necessitating meticulous management, including replacement therapy with clotting factors. This research examines the records of [...] Read more.
This retrospective cohort study evaluates the safety and efficacy of replacement therapy with regard to pregnancy outcomes in hemophilia carriers. Hemophilia carriers face elevated bleeding risks during pregnancy, necessitating meticulous management, including replacement therapy with clotting factors. This research examines the records of 64 pregnant hemophilia carriers at King Fahad Medical City, Riyadh, from January 2010 to December 2023, analyzing their demographic details, hemophilia type and severity, replacement therapy specifics, and pregnancy outcomes. The study found that 62.5% of the participants had hemophilia A, with 43.8% categorized as severe. Most subjects (87.5%) received recombinant factor VIII at a median dosage of 30 IU/kg weekly. Adverse pregnancy outcomes included gestational hypertension (15.6%), preterm labor (18.8%), and postpartum hemorrhage (12.5%). The cesarean section rate was 28.1%. Neonatal outcomes were generally favorable, with median birth weights at 3100 g and mean Apgar scores of 8.2 and 9.1 at 1 and 5 min, respectively. Logistic regression analysis revealed no significant association between adverse events and therapy type or dosage, though a trend towards significance was noted with once-weekly administration (p = 0.082). The study concludes that replacement therapy is a viable method for managing hemophilia in pregnant carriers, leading to generally favorable maternal and neonatal outcomes. However, it underscores the importance of individualized treatment plans and close monitoring to effectively manage the risks associated with hemophilia during pregnancy. Full article
(This article belongs to the Special Issue Hemophilia)
14 pages, 1482 KiB  
Review
Proteogenomics in Nephrology: A New Frontier in Nephrological Research
by Kavya Chavali, Holley Coker, Emily Youngblood and Oleg Karaduta
Curr. Issues Mol. Biol. 2024, 46(5), 4595-4608; https://doi.org/10.3390/cimb46050279 (registering DOI) - 11 May 2024
Abstract
Proteogenomics represents a transformative intersection in nephrology, uniting genomics, transcriptomics, and proteomics to unravel the molecular intricacies of kidney diseases. This review encapsulates the methodological essence of proteogenomics and its profound implications in chronic kidney disease (CKD) research. We explore the proteogenomic pipeline, [...] Read more.
Proteogenomics represents a transformative intersection in nephrology, uniting genomics, transcriptomics, and proteomics to unravel the molecular intricacies of kidney diseases. This review encapsulates the methodological essence of proteogenomics and its profound implications in chronic kidney disease (CKD) research. We explore the proteogenomic pipeline, highlighting the integrated analysis of genomic, transcriptomic, and proteomic data and its pivotal role in enhancing our understanding of kidney pathologies. Through case studies, we showcase the application of proteogenomics in clear cell renal cell carcinoma (ccRCC) and Autosomal Recessive Polycystic Kidney Disease (ARPKD), emphasizing its potential in personalized treatment strategies and biomarker discovery. The review also addresses the challenges in proteogenomic analysis, including data integration complexities and bioinformatics limitations, and proposes solutions for advancing the field. Ultimately, this review underscores the prospective future of proteogenomics in nephrology, particularly in advancing personalized medicine and providing novel therapeutic insights. Full article
(This article belongs to the Section Molecular Medicine)
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17 pages, 293 KiB  
Article
Multivariate and Matrix-Variate Logistic Models in the Real and Complex Domains
by A. M. Mathai
Stats 2024, 7(2), 445-461; https://doi.org/10.3390/stats7020027 (registering DOI) - 11 May 2024
Abstract
Several extensions of the basic scalar variable logistic density to the multivariate and matrix-variate cases, in the real and complex domains, are given where the extended forms end up in extended zeta functions. Several cases of multivariate and matrix-variate Bayesian procedures, in the [...] Read more.
Several extensions of the basic scalar variable logistic density to the multivariate and matrix-variate cases, in the real and complex domains, are given where the extended forms end up in extended zeta functions. Several cases of multivariate and matrix-variate Bayesian procedures, in the real and complex domains, are also given. It is pointed out that there are a range of applications of Gaussian and Wishart-based matrix-variate distributions in the complex domain in multi-look data from radar and sonar. It is hoped that the distributions derived in this paper will be highly useful in such applications in physics, engineering, statistics and communication problems, because, in the real scalar case, a logistic model is seen to be more appropriate compared to a Gaussian model in many industrial applications. Hence, logistic-based multivariate and matrix-variate distributions, especially in the complex domain, are expected to perform better where Gaussian and Wishart-based distributions are currently used. Full article
16 pages, 982 KiB  
Article
Optimisation of Synchronous Grouting Mix Ratio for Shield Tunnels
by Hongmei Zhou, Yixiang Zhang, Wanxu Zhu, Qingyu Zhong and Xinyu Huang
Appl. Sci. 2024, 14(10), 4098; https://doi.org/10.3390/app14104098 (registering DOI) - 11 May 2024
Abstract
During shield construction in underground spaces, synchronous grouting slurry is poured between the surrounding rock and tunnel lining to ensure stability. For synchronous grouting slurries, few studies have investigated the relationship between the rheological parameters and physical properties, grout-segregation mechanism, and anti-segregation performance. [...] Read more.
During shield construction in underground spaces, synchronous grouting slurry is poured between the surrounding rock and tunnel lining to ensure stability. For synchronous grouting slurries, few studies have investigated the relationship between the rheological parameters and physical properties, grout-segregation mechanism, and anti-segregation performance. Therefore, we explored the relationships between the slurry rheological parameters, segregation rate, and bleeding rate. Cement, sand, fly ash, and bentonite were used to prepare the slurry, and the effects of different polycarboxylate water-reducing agents and dispersible latex powder dosages were studied. The rheological parameters of 16 groups of uniformly designed slurries were tested, and the data were fit using the Herschel–Bulkley model. The optimal mix ratio lowered the slurry segregation rate, and its rheological behaviour was consistent with the Herschel–Bulkley fluid characteristics. High-yield-shear-stress synchronous grouting slurries with high and low viscosity coefficients were less likely to bleed and segregate, respectively. The optimised slurry fluidity, 3 h bleeding rate, 24 h bleeding rate, segregation rate, coagulation time, and 28 days compressive strength were 257.5 mm, 0.71%, 0.36%, 3.1%, 6.7 h, and 2.61 MPa, respectively, which meet the requirements of a synchronous grouting slurry of shield tunnels for sufficiently preventing soil disturbance and deformation in areas surrounding underground construction sites. Full article
21 pages, 1902 KiB  
Article
Quality Assessment of Loquat under Different Preservation Methods Based on Physicochemical Indicators, GC–MS and Intelligent Senses
by Mingfeng Qiao, Siyue Luo, Zherenyongzhong Z., Xuemei Cai, Xinxin Zhao, Yuqin Jiang and Baohe Miao
Horticulturae 2024, 10(5), 499; https://doi.org/10.3390/horticulturae10050499 (registering DOI) - 11 May 2024
Abstract
To explore the effects of different preservation methods on the quality of loquat after fresh-keeping treatment, various preservation techniques were employed. These included natural preservation (NP), vacuum freezing preservation (VFP), vacuum at room temperature preservation (VP) and freezing preservation (FP). The quality assessment [...] Read more.
To explore the effects of different preservation methods on the quality of loquat after fresh-keeping treatment, various preservation techniques were employed. These included natural preservation (NP), vacuum freezing preservation (VFP), vacuum at room temperature preservation (VP) and freezing preservation (FP). The quality assessment involved analyzing the effects of these preservation methods using physicochemical indexes, a colorimeter, an electronic nose (E-nose), an electronic tongue (E-tongue) and gas chromatography–mass spectrometry (GC–MS). The results showed minor differences in loquat quality under different preservation methods, with sensory scores ranging from 55 to 78 and ΔE values ranging from 11.92 to 18.59. Significant variations were observed in moisture content (ranging from 53.20 g/100 g to 87.20 g/100 g), calorie content (ranging from 42.55 Kcal/100 g to 87.30 Kcal/100 g), adhesion (ranging from 0.92 to 1.84 mJ) and hardness (ranging from 2.97 to 4.19 N) (p < 0.05). Additionally, the free amino acid content varied from 22.47 mg/g to 65.42 mg/g. GC–MS analysis identified a total of 47 volatile flavor substances in varieties of loquats, including 13 aldehydes, 9 esters, 6 ketones, 2 acids, 3 alcohols, 2 phenols, 3 pyrazines, 1 furan and 8 other substances. The relative content of aldehydes was significantly higher than that of other chemicals. The VFP and FP samples exhibited higher aldehyde content compared to the NP and VP samples. Moreover, Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) revealed 18 marked compounds that could differentiate between 5 loquat species. Analysis using E-nose and E-tongue indicated significant changes in the olfactory and gustatory senses of loquats following preservation. The VFP samples demonstrated the most effective preservation of loquat quality with minimal impact. This study provides some theoretical guidance for the home preservation of loquats. Full article
13 pages, 1952 KiB  
Article
Electrical Sensor Calibration by Fuzzy Clustering with Mandatory Constraint
by Shihong Yue, Keyi Fu, Liping Liu and Yuwei Zhao
Sensors 2024, 24(10), 3068; https://doi.org/10.3390/s24103068 (registering DOI) - 11 May 2024
Abstract
Electrical tomography sensors have been widely used for pipeline parameter detection and estimation. Before they can be used in formal applications, the sensors must be calibrated using enough labeled data. However, due to the high complexity of actual measuring environments, the calibrated sensors [...] Read more.
Electrical tomography sensors have been widely used for pipeline parameter detection and estimation. Before they can be used in formal applications, the sensors must be calibrated using enough labeled data. However, due to the high complexity of actual measuring environments, the calibrated sensors are inaccurate since the labeling data may be uncertain, inconsistent, incomplete, or even invalid. Alternatively, it is always possible to obtain partial data with accurate labels, which can form mandatory constraints to correct errors in other labeling data. In this paper, a semi-supervised fuzzy clustering algorithm is proposed, and the fuzzy membership degree in the algorithm leads to a set of mandatory constraints to correct these inaccurate labels. Experiments in a dredger validate the proposed algorithm in terms of its accuracy and stability. This new fuzzy clustering algorithm can generally decrease the error of labeling data in any sensor calibration process. Full article
(This article belongs to the Section Electronic Sensors)
16 pages, 12295 KiB  
Article
Ghost Fringe Suppression by Modifying the f-Number of the Diverger Lens for the Interferometric Measurement of Catadioptric Telescopes
by Yi-Kai Huang and Cheng-Huan Chen
Photonics 2024, 11(5), 453; https://doi.org/10.3390/photonics11050453 (registering DOI) - 11 May 2024
Abstract
A high-precision catadioptric telescope such as a space-borne telescope is usually tested with interferometer to check the optical quality in assembly. The coarse and fine alignment of the telescope are mainly based on the information from the coordinate measuring machine and the fringe [...] Read more.
A high-precision catadioptric telescope such as a space-borne telescope is usually tested with interferometer to check the optical quality in assembly. The coarse and fine alignment of the telescope are mainly based on the information from the coordinate measuring machine and the fringe pattern of the interferometer, respectively. In addition, further fine-tuning can be achieved according to the variation in wavefront error and Zernike data. The issue is that the vast majority of the catadioptric telescopes contain plural lens surfaces which could produce unwanted ghost fringes, disturbing the wavefront measurement. Technically, off-axis installation to shift away ghost fringes from central interferogram could be acceptable in some cases. Nevertheless, in this paper, the source of ghost fringe in interferometric measurement for catadioptric telescopes is investigated with light path simulation, and a solution of reducing the f-number of the diverger lens is proposed to eliminate the ghost fringe disturbance. Both simulation and experimental results verify the effectiveness of the proposed concept. Full article
(This article belongs to the Special Issue Optical Systems for Astronomy)
20 pages, 959 KiB  
Article
The Impact of CSI SEEE Carbon Neutral Index Launched on Order Aggressiveness
by Zihuang Huang, Xiaoyu Zhang and Kaifeng Li
J. Risk Financial Manag. 2024, 17(5), 198; https://doi.org/10.3390/jrfm17050198 (registering DOI) - 11 May 2024
Abstract
In the context of carbon peaking and carbon neutrality goals, in order to clarify the investment direction for investors, China Securities Index Co., Ltd. (CSI) has collaborated with the Shanghai Environmental Energy Exchange to develop the CSI SEEE Carbon Neutral Index (CSCNI), which [...] Read more.
In the context of carbon peaking and carbon neutrality goals, in order to clarify the investment direction for investors, China Securities Index Co., Ltd. (CSI) has collaborated with the Shanghai Environmental Energy Exchange to develop the CSI SEEE Carbon Neutral Index (CSCNI), which has also played a leading role in the subsequent preparation of the Green Finance Index. The launch of this index has sparked research interest among scholars in stimulating investor order aggressiveness. This study employs event study methodology to examine the impact of the CSCNI launch on order aggressiveness. The sample companies are categorized into two groups: deep low-carbon and high-carbon reduction, with a focus on studying buy and sale order aggressiveness. The results indicate that the launch of CSCNI has mobilized order aggressiveness but has led to a negative stock price effect as investors anticipate an increase in environmental costs for the sample companies. Furthermore, we reveal that the long-term growth potential of the deep low-carbon field is more promising compared to the high-carbon reduction sector, making stocks in the deep low-carbon field more attractive. The launch of CSCNI has shown contrasting effects on the buy and sale order aggressiveness of investors, with the impact of the index announcement being more significant on the sample companies. This research provides valuable insights for evaluating the impact of green finance indices and contributes to the understanding of internal mechanisms. It provides an important reference for financial regulators to evaluate the development of the current green index. At the same time, it expands the domestic research on order aggressiveness, which studies the action mechanism of the stock price effect of the green stock index from the perspective of order aggressiveness. Full article
(This article belongs to the Special Issue Advances in Macroeconomics and Financial Markets)
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27 pages, 3320 KiB  
Article
Characteristics and Reservoir Development Model of the Unconformity Caused by Huaiyuan Movement in Bohai Bay Basin, China: A Case Study of Chengdao-Zhuanghai Buried Hill in Jiyang Depression
by Ruijuan Liu, Guozhi Wang, Yongshi Wang, Xuefeng Hao, Feng Qin, Xianxu Fang, Wei Meng and Gang Liu
J. Mar. Sci. Eng. 2024, 12(5), 804; https://doi.org/10.3390/jmse12050804 (registering DOI) - 11 May 2024
Abstract
It is beneficial in terms of the theoretical significance and application prospects to define the structure and reservoir development model of the lower Paleozoic unconformity in the Jiyang Depression of Bohai Bay Basin, China, for oil and gas exploration of unconformity in carbonate [...] Read more.
It is beneficial in terms of the theoretical significance and application prospects to define the structure and reservoir development model of the lower Paleozoic unconformity in the Jiyang Depression of Bohai Bay Basin, China, for oil and gas exploration of unconformity in carbonate strata. Geological and geochemical evidence shows that a regional unconformity formed during the Huaiyuan Movement in the lower Paleozoic strata of the Jiyang Depression. Along the top of the regional unconformity between the Yeli Liangjiashan Formation and Fengshan Formation, various types of karst breccia have developed, showing prominent characteristics of development and vertical karst zonation. The paleokarst zone can be divided into the vadose zone and the underflow zone, and there are apparent differences between the two zones in terms of the mode of karst activity and type of reservoir space. Primitive sedimentary microfacies, dolomitization, and supergene karstification controlled the reservoirs of the Fengshan Formation and Yeli-Liangjiashan Formation. There are significant differences in the original physical properties due to the differences in the original sedimentary microfacies. The pore development of granular dolomite of high-energy beach facies has the best reservoir performance. In the later period, the superposition of dolomitization and supergene karstification resulted in apparent differences in karst development mode, development intensity, reservoir type, and reservoir physical properties. Among them, the granular dolomite reservoir has the best physical properties and has developed a cavity-type reservoir that has a planar distribution along an unconformity surface. Full article
(This article belongs to the Special Issue High-Efficient Exploration and Development of Oil & Gas from Ocean—2nd Edition)
15 pages, 5573 KiB  
Article
Axial Tensile Ultimate Strength of an Unbonded Flexible Riser Based on a Numerical Method
by Dongya Li, Wanchao Jiang, Qingqing Xing and Qingsheng Liu
Materials 2024, 17(10), 2286; https://doi.org/10.3390/ma17102286 (registering DOI) - 11 May 2024
Abstract
Unbonded flexible risers consist of several helical and cylindrical layers, which can undergo large bending deformation and can be installed to different configurations to adapt to harsh marine environments, and is a key equipment in transporting oil and gas resources from Ultra Deep [...] Read more.
Unbonded flexible risers consist of several helical and cylindrical layers, which can undergo large bending deformation and can be installed to different configurations to adapt to harsh marine environments, and is a key equipment in transporting oil and gas resources from Ultra Deep Waters (UDWs) to offshore platforms. The helical interlayer of an unbonded flexible riser makes the structural behavior difficult to predict. In this paper, the axial tensile behavior and the axial tensile ultimate strength of an unbonded flexible riser are studied based on a typical 2.5-inch eight-layer unbonded flexible riser model, and verified through a theoretical method considering the contact between adjacent layers. First, the balance equation of separate layers is deduced by a functional principle, and then the overall theoretical model of an unbonded flexible riser is established considering the geometric relationship between adjacent layers. Then, the numerical model considering the detailed geometric properties of an unbonded flexible riser is established to simulate the axial tensile behavior. Finally, after being verified through the experimental results, the axial tensile stiffness and axial tensile strength of an unboned flexible riser considering the elasticity of the tensile armor layer are studied using the proposed two methods. Additionally, the effect of frictional coefficients is conducted. The numerical and theoretical results show good agreement with the test results, and the friction between adjacent layers would increase the axial tensile stiffness of an unbonded flexible riser. Full article
(This article belongs to the Special Issue Plastic Forming Process and Microstructure Evolution of Hard-to-Deform Metals)
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90 pages, 46719 KiB  
Systematic Review
IoT Solutions with Artificial Intelligence Technologies for Precision Agriculture: Definitions, Applications, Challenges, and Opportunities
by Elisha Elikem Kofi Senoo, Lia Anggraini, Jacqueline Asor Kumi, Luna Bunga Karolina, Ebenezer Akansah, Hafeez Ayo Sulyman, Israel Mendonça and Masayoshi Aritsugi
Electronics 2024, 13(10), 1894; https://doi.org/10.3390/electronics13101894 (registering DOI) - 11 May 2024
Abstract
The global agricultural sector confronts significant obstacles such as population growth, climate change, and natural disasters, which negatively impact food production and pose a threat to food security. In response to these challenges, the integration of IoT and AI technologies emerges as a [...] Read more.
The global agricultural sector confronts significant obstacles such as population growth, climate change, and natural disasters, which negatively impact food production and pose a threat to food security. In response to these challenges, the integration of IoT and AI technologies emerges as a promising solution, facilitating data-driven decision-making, optimizing resource allocation, and enhancing monitoring and control systems in agricultural operations to address these challenges and promote sustainable farming practices. This study examines the intersection of IoT and AI in precision agriculture (PA), aiming to provide a comprehensive understanding of their combined impact and mutually reinforcing relationship. Employing a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, we explore the synergies and transformative potential of integrating IoT and AI in agricultural systems. The review also aims to identify present trends, challenges, and opportunities in utilizing IoT and AI in agricultural systems. Diverse forms of agricultural practices are scrutinized to discern the applications of IoT and AI systems. Through a critical analysis of existing literature, this study contributes to a deeper understanding of how the integration of IoT and AI technologies can revolutionize PA, resulting in improved efficiency, sustainability, and productivity in the agricultural sector. Full article
(This article belongs to the Special Issue The Future of IoT: Advanced AI Based IoT Technologies and Applications)
13 pages, 3676 KiB  
Communication
C(sp)-C(sp) Lever-Based Targets of Orientational Chirality: Design and Asymmetric Synthesis
by Ting Xu, Jia-Yin Wang, Yu Wang, Shengzhou Jin, Yao Tang, Sai Zhang, Qingkai Yuan, Hao Liu, Wenxin Yan, Yinchun Jiao, Xiao-Liang Yang and Guigen Li
Molecules 2024, 29(10), 2274; https://doi.org/10.3390/molecules29102274 (registering DOI) - 11 May 2024
Abstract
In this study, the design and asymmetric synthesis of a series of chiral targets of orientational chirality were conducted by taking advantage of N-sulfinylimine-assisted nucleophilic addition and modified Sonogashira catalytic coupling systems. Orientational isomers were controlled completely using alkynyl/alkynyl levers [C(sp)-C(sp) axis] [...] Read more.
In this study, the design and asymmetric synthesis of a series of chiral targets of orientational chirality were conducted by taking advantage of N-sulfinylimine-assisted nucleophilic addition and modified Sonogashira catalytic coupling systems. Orientational isomers were controlled completely using alkynyl/alkynyl levers [C(sp)-C(sp) axis] with absolute configuration assignment determined by X-ray structural analysis. The key structural element of the resulting orientational chirality is uniquely characterized by remote through-space blocking. Forty examples of multi-step synthesis were performed, with modest to good yields and excellent orientational selectivity. Several chiral orientational amino targets are attached with scaffolds of natural and medicinal products, showing potential pharmaceutical and medical applications in the future. Full article
(This article belongs to the Section Organic Chemistry)
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11 pages, 382 KiB  
Article
A Study of Environmental Organizations in Puerto Rico Advocating for Social and Environmental Justice
by Clara E. Rodriguez and Carmen Collins
Soc. Sci. 2024, 13(5), 260; https://doi.org/10.3390/socsci13050260 (registering DOI) - 11 May 2024
Abstract
After Hurricane Maria devastated Puerto Rico, we wanted to determine how the islanders viewed environmental organizations as part of an effort to understand the relationships between attitudes, institutions, and environmental and social justice issues. As a category 5 hurricane, Hurricane Maria was one [...] Read more.
After Hurricane Maria devastated Puerto Rico, we wanted to determine how the islanders viewed environmental organizations as part of an effort to understand the relationships between attitudes, institutions, and environmental and social justice issues. As a category 5 hurricane, Hurricane Maria was one of the strongest to hit Puerto Rico. Yet, the US mainstream media coverage of this and other environmental issues was lacking. From a total of 90 environmental organizations in Puerto Rico, we surveyed 19 that were active in the southwest of the island. We asked: (1) How do local people view environmental and social justice issues and (2) given their organizations’ efforts to deal with these issues, what are their successes? To address these questions, we developed a survey in English and Spanish and conducted personal and online interviews with 30 relevant individuals. Their most successful outcomes included: (1) educating and creating greater awareness of environmental issues; (2) introducing environmental changes into their communities; and (3) becoming and surviving as economically sustainable organizations. The results inform our understanding between environmental organizations and social and environmental justice in Puerto Rico and more broadly, because the organizations surveyed are at the center of fighting climate change and achieving environmental justice. Full article
(This article belongs to the Special Issue Social and Environmental Justice)
13 pages, 815 KiB  
Article
Characterizing Spatial and Temporal Variations in N2O Emissions from Dairy Manure Management in China Based on IPCC Methodology
by Bin Hu, Lijie Zhang, Chao Liang, Xiao Yang, Zhengxiang Shi and Chaoyuan Wang
Agriculture 2024, 14(5), 753; https://doi.org/10.3390/agriculture14050753 (registering DOI) - 11 May 2024
Abstract
The emission factor method (Tier 1) recommended by the Intergovernmental Panel on Climate Change (IPCC) is commonly used to estimate greenhouse gas (GHG) emissions from livestock and poultry farms. However, the estimation accuracy may vary due to practical differences in manure management across [...] Read more.
The emission factor method (Tier 1) recommended by the Intergovernmental Panel on Climate Change (IPCC) is commonly used to estimate greenhouse gas (GHG) emissions from livestock and poultry farms. However, the estimation accuracy may vary due to practical differences in manure management across China. The objectives of this study were to estimate the direct and indirect nitrous oxide (N2O) emissions from dairy manure management between 1990 and 2021 in China and characterize its spatial and temporal variations following IPCC guideline Tier 2. The N2O emission factor (EF) of dairy cow manure management systems was determined at the national level and regional level as well. The results showed that the national cumulative N2O emission of manure management from 1990 to 2021 was 113.1million tons of CO2 equivalent, ranging from 90.3 to 135.9 million tons with an uncertainty of ±20.2%. The annual EF was 0.021 kg N2O-N (kg N)−1 for total emissions, while it was 0.014 kg N2O-N (kg N)−1 for direct emissions. The proportions of N2O emissions in North China, Northeast China, East China, Central and Southern China, Southwest China and Northwest China were 32.3%, 18.6%, 11.4%, 5.8%, 6.1% and 25.8%, respectively. In addition, N2O emissions varied among farms in different scales. The respective proportions of total N2O emissions from small-scale and large-scale farms were 64.8% and 35.2% in the past three decades. With the improvement in farm management and milk production efficiency, the N2O emissions per unit mass of milk decreased from 0.77 × 10−3 kg to 0.48 × 10−3 kg in 1990–2021. This study may provide important insights into compiling a GHG emission inventory and developing GHG emission reduction strategies for the dairy farming system in China. Full article
(This article belongs to the Section Ecosystem, Environment and Climate Change in Agriculture)
27 pages, 3418 KiB  
Review
Composition of Lignocellulose Hydrolysate in Different Biorefinery Strategies: Nutrients and Inhibitors
by Yilan Wang, Yuedong Zhang, Qiu Cui, Yingang Feng and Jinsong Xuan
Molecules 2024, 29(10), 2275; https://doi.org/10.3390/molecules29102275 (registering DOI) - 11 May 2024
Abstract
The hydrolysis and biotransformation of lignocellulose, i.e., biorefinery, can provide human beings with biofuels, bio-based chemicals, and materials, and is an important technology to solve the fossil energy crisis and promote global sustainable development. Biorefinery involves steps such as pretreatment, saccharification, and fermentation, [...] Read more.
The hydrolysis and biotransformation of lignocellulose, i.e., biorefinery, can provide human beings with biofuels, bio-based chemicals, and materials, and is an important technology to solve the fossil energy crisis and promote global sustainable development. Biorefinery involves steps such as pretreatment, saccharification, and fermentation, and researchers have developed a variety of biorefinery strategies to optimize the process and reduce process costs in recent years. Lignocellulosic hydrolysates are platforms that connect the saccharification process and downstream fermentation. The hydrolysate composition is closely related to biomass raw materials, the pretreatment process, and the choice of biorefining strategies, and provides not only nutrients but also possible inhibitors for downstream fermentation. In this review, we summarized the effects of each stage of lignocellulosic biorefinery on nutrients and possible inhibitors, analyzed the huge differences in nutrient retention and inhibitor generation among various biorefinery strategies, and emphasized that all steps in lignocellulose biorefinery need to be considered comprehensively to achieve maximum nutrient retention and optimal control of inhibitors at low cost, to provide a reference for the development of biomass energy and chemicals. Full article
(This article belongs to the Special Issue Biomass and Waste Conversion and Valorization to Chemicals, Energy and Fuels)
16 pages, 1244 KiB  
Article
Undescribed Cyclohexene and Benzofuran Alkenyl Derivatives from Choerospondias axillaris, a Potential Hypoglycemic Fruit
by Ermias Tamiru Weldetsadik, Na Li, Jingjuan Li, Jiahuan Shang, Hongtao Zhu and Yingjun Zhang
Foods 2024, 13(10), 1495; https://doi.org/10.3390/foods13101495 (registering DOI) - 11 May 2024
Abstract
The fruit of Choerospondias axillaris (Anacardiaceae), known as south wild jujube in China, has been consumed widely in several regions of the world to produce fruit pastille and leathers, juice, jam, and candy. A comprehensive chemical study on the fresh fruits led to [...] Read more.
The fruit of Choerospondias axillaris (Anacardiaceae), known as south wild jujube in China, has been consumed widely in several regions of the world to produce fruit pastille and leathers, juice, jam, and candy. A comprehensive chemical study on the fresh fruits led to the isolation and identification of 18 compounds, including 7 new (1–7) and 11 known (8–18) comprised of 5 alkenyl (cyclohexenols and cyclohexenones) derivatives (1–5), 3 benzofuran derivatives (6–8), 6 flavonoids (9–14) and 4 lignans (15–18). Their structures were elucidated by extensive spectroscopic analysis. The known lignans 15–18 were isolated from the genus Choerospondias for the first time. Most of the isolates exhibited significant inhibitory activity on α-glucosidase with IC50 values from 2.26 ± 0.06 to 43.9 ± 0.96 μM. Molecular docking experiments strongly supported the potent α-glucosidase inhibitory activity. The results indicated that C. axillaris fruits could be an excellent source of functional foods that acquire potential hypoglycemic bioactive components. Full article
(This article belongs to the Section Nutraceuticals, Functional Foods, and Novel Foods)
25 pages, 2932 KiB  
Article
Physiological and Proteomic Responses of the Tetraploid Robinia pseudoacacia L. to High CO2 Levels
by Jianxin Li, Subin Zhang, Pei Lei, Liyong Guo, Xiyang Zhao and Fanjuan Meng
Int. J. Mol. Sci. 2024, 25(10), 5262; https://doi.org/10.3390/ijms25105262 (registering DOI) - 11 May 2024
Abstract
The increase in atmospheric CO2 concentration is a significant factor in triggering global warming. CO2 is essential for plant photosynthesis, but excessive CO2 can negatively impact photosynthesis and its associated physiological and biochemical processes. The tetraploid Robinia pseudoacacia L., a [...] Read more.
The increase in atmospheric CO2 concentration is a significant factor in triggering global warming. CO2 is essential for plant photosynthesis, but excessive CO2 can negatively impact photosynthesis and its associated physiological and biochemical processes. The tetraploid Robinia pseudoacacia L., a superior and improved variety, exhibits high tolerance to abiotic stress. In this study, we investigated the physiological and proteomic response mechanisms of the tetraploid R. pseudoacacia under high CO2 treatment. The results of our physiological and biochemical analyses revealed that a 5% high concentration of CO2 hindered the growth and development of the tetraploid R. pseudoacacia and caused severe damage to the leaves. Additionally, it significantly reduced photosynthetic parameters such as Pn, Gs, Tr, and Ci, as well as respiration. The levels of chlorophyll (Chl a and b) and the fluorescent parameters of chlorophyll (Fm, Fv/Fm, qP, and ETR) also significantly decreased. Conversely, the levels of ROS (H2O2 and O2·−) were significantly increased, while the activities of antioxidant enzymes (SOD, CAT, GR, and APX) were significantly decreased. Furthermore, high CO2 induced stomatal closure by promoting the accumulation of ROS and NO in guard cells. Through a proteomic analysis, we identified a total of 1652 DAPs after high CO2 treatment. GO functional annotation revealed that these DAPs were mainly associated with redox activity, catalytic activity, and ion binding. KEGG analysis showed an enrichment of DAPs in metabolic pathways, secondary metabolite biosynthesis, amino acid biosynthesis, and photosynthetic pathways. Overall, our study provides valuable insights into the adaptation mechanisms of the tetraploid R. pseudoacacia to high CO2. Full article
(This article belongs to the Special Issue Molecular Advance in Abiotic Stress Signaling in Plants: Focus on Atmospheric Stressors)
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21 pages, 6306 KiB  
Article
Predicting the Occurrence of Forest Fire in the Central-South Region of China
by Quansheng Hai, Xiufeng Han, Battsengel Vandansambuu, Yuhai Bao, Byambakhuu Gantumur, Sainbuyan Bayarsaikhan, Narantsetseg Chantsal and Hailian Sun
Forests 2024, 15(5), 844; https://doi.org/10.3390/f15050844 (registering DOI) - 11 May 2024
Abstract
Understanding the spatial and temporal patterns of forest fires, along with the key factors influencing their occurrence, and accurately forecasting these events are crucial for effective forest management. In the Central-South region of China, forest fires pose a significant threat to the ecological [...] Read more.
Understanding the spatial and temporal patterns of forest fires, along with the key factors influencing their occurrence, and accurately forecasting these events are crucial for effective forest management. In the Central-South region of China, forest fires pose a significant threat to the ecological system, public safety, and economic stability. This study employs Geographic Information Systems (GISs) and the LightGBM (Light Gradient Boosting Machine) model to identify the determinants of forest fire incidents and develop a predictive model for the likelihood of forest fire occurrences, in addition to proposing a zoning strategy. The purpose of the study is to enhance our understanding of forest fire dynamics in the Central-South region of China and to provide actionable insights for mitigating the risks associated with such disasters. The findings reveal the following: (i) Spatially, fire incidents exhibit significant clustering and autocorrelation, highlighting areas with heightened likelihood. (ii) The Central-South Forest Fire Likelihood Prediction Model demonstrates high accuracy, reliability, and predictive capability, with performance metrics such as accuracy, precision, recall, and F1 scores exceeding 85% and AUC values above 89%, proving its effectiveness in forecasting the likelihood of forest fires and differentiating between fire scenarios. (iii) The likelihood of forest fires in the Central-South region of China varies across regions and seasons, with increased likelihood observed from March to May in specific provinces due to various factors, including weather conditions and leaf litter accumulation. Risks of localized fires are noted from June to August and from September to November in different areas, while certain regions continue to face heightened likelihood from December to February. Full article
(This article belongs to the Special Issue Integrated Measurements for Precision Forestry)
14 pages, 425 KiB  
Article
A Neural Network Forecasting Approach for the Smart Grid Demand Response Management Problem
by Slim Belhaiza and Sara Al-Abdallah
Energies 2024, 17(10), 2329; https://doi.org/10.3390/en17102329 (registering DOI) - 11 May 2024
Abstract
Demand response management (DRM) plays a crucial role in the prospective development of smart grids. The precise estimation of electricity demand for individual houses is vital for optimizing the operation and planning of the power system. Accurate forecasting of the required components holds [...] Read more.
Demand response management (DRM) plays a crucial role in the prospective development of smart grids. The precise estimation of electricity demand for individual houses is vital for optimizing the operation and planning of the power system. Accurate forecasting of the required components holds significance as it can substantially impact the final cost, mitigate risks, and support informed decision-making. In this paper, a forecasting approach employing neural networks for smart grid demand-side management is proposed. The study explores various enhanced artificial neural network (ANN) architectures for forecasting smart grid consumption. The performance of the ANN approach in predicting energy demands is evaluated through a comparison with three statistical models: a time series model, an auto-regressive model, and a hybrid model. Experimental results demonstrate the ability of the proposed neural network framework to deliver accurate and reliable energy demand forecasts. Full article
(This article belongs to the Topic AI and Computational Methods for Modelling, Simulations and Optimizing of Advanced Systems: Innovations in Complexity)
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