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21 pages, 4636 KiB  
Article
Molecular Characteristics, Expression Patterns, and Response of Insulin-like Growth Factors Gene Induced by Sex Steroid Hormones in Blotched Snakehead (Channa maculata)
by Xiaotian Zhang, Yuxia Wu, Yang Zhang, Jin Zhang, Kunci Chen, Haiyang Liu, Qing Luo, Shuzhan Fei, Jian Zhao and Mi Ou
Fishes 2024, 9(4), 120; https://doi.org/10.3390/fishes9040120 (registering DOI) - 28 Mar 2024
Abstract
Insulin-like growth factors (IGFs) play central roles in the growth and development of vertebrates. Blotched snakehead (Channa maculata), an economically significant fish, exhibits obvious sexual dimorphism and achieves sexual maturity in one year. However, the role of IGFs in C. maculata [...] Read more.
Insulin-like growth factors (IGFs) play central roles in the growth and development of vertebrates. Blotched snakehead (Channa maculata), an economically significant fish, exhibits obvious sexual dimorphism and achieves sexual maturity in one year. However, the role of IGFs in C. maculata remains unknown. Three IGF genes were identified in C. maculata, designated as CmIGF1-1, CmIGF1-2, and CmIGF2. The cDNA sequences of these genes are 1184, 655, and 695 bp, encoding putative proteins of 168, 131, and 215 amino acids, respectively, and all three proteins contain a conserved IGF domain. Quantitative real-time PCR (qPCR) revealed the predominant expression of CmIGFs in the liver of adult fish, with higher expression levels observed in males. Notably, CmIGF1-1, CmIGF1-2, and CmIGF2 displayed analogous expression profiles in the liver across various developmental stages, peaking at 365 days after hatching (dah). Subsequently, 600 individuals at 75 dah, at an early developmental stage, were randomly divided equally into six groups and reared in aerated 2 m × 2 m × 2 m cement ponds at 26.0 ± 1.0 °C. Following a one-week acclimatization period, fish without observed abnormalities were intraperitoneally injected with either 17α-ethynylestradiol (EE2) or 17α-methyltestosterone (MT) at a dose of 10 μg/g body weight. Three groups underwent short-term hormone treatment, and the remaining three groups underwent long-term hormone treatment, which included five injections at two-week intervals over ten weeks. The analysis of CmIGFs expression levels in the liver under different hormone treatments revealed that EE2 suppressed the expression of CmIGF1-1 and CmIGF1-2 while promoting CmIGF2 expression. In females, MT up-regulated the expression of CmIGF1-1 and CmIGF2 in a time-dependent manner, but consistently inhibited CmIGF2 expression. In males, MT promoted the expression of CmIGFs in a time-dependent manner, reaching peak levels for CmIGF1-1, CmIGF1-2, and CmIGF2 after 8, 10, and 2 weeks of injection, respectively. Additionally, CmIGF1 and CmIGF2 might exhibit a complementary relationship, with a compensatory increase in CmIGF2 expression in response to low CmIGF1 concentration. These findings highlight the potential key role of IGFs upon growth and their regulation by sex steroid hormones in C. maculata, providing a crucial foundation for future research aimed at elucidating the molecular mechanisms underlying the growth dimorphism between female and male blotched snakeheads. Full article
(This article belongs to the Special Issue Genetics and Breeding in Aquaculture)
21 pages, 3650 KiB  
Article
Dynamic Events in the Flexible Job-Shop Scheduling Problem: Rescheduling with a Hybrid Metaheuristic Algorithm
by Shubhendu Kshitij Fuladi and Chang-Soo Kim
Algorithms 2024, 17(4), 142; https://doi.org/10.3390/a17040142 (registering DOI) - 28 Mar 2024
Abstract
In the real world of manufacturing systems, production planning is crucial for organizing and optimizing various manufacturing process components. The objective of this paper is to present a methodology for both static scheduling and dynamic scheduling. In the proposed method, a hybrid algorithm [...] Read more.
In the real world of manufacturing systems, production planning is crucial for organizing and optimizing various manufacturing process components. The objective of this paper is to present a methodology for both static scheduling and dynamic scheduling. In the proposed method, a hybrid algorithm is utilized to optimize the static flexible job-shop scheduling problem (FJSP) and dynamic flexible job-shop scheduling problem (DFJSP). This algorithm integrates the genetic algorithm (GA) as a global optimization technique with a simulated annealing (SA) algorithm serving as a local search optimization approach to accelerate convergence and prevent getting stuck in local minima. Additionally, variable neighborhood search (VNS) is utilized for efficient neighborhood search within this hybrid algorithm framework. For the FJSP, the proposed hybrid algorithm is simulated on a 40-benchmark dataset to evaluate its performance. Comparisons among the proposed hybrid algorithm and other algorithms are provided to show the effectiveness of the proposed algorithm, ensuring that the proposed hybrid algorithm can efficiently solve the FJSP, with 38 out of 40 instances demonstrating better results. The primary objective of this study is to perform dynamic scheduling on two datasets, including both single-purpose machine and multi-purpose machine datasets, using the proposed hybrid algorithm with a rescheduling strategy. By observing the results of the DFJSP, dynamic events such as a single machine breakdown, a single job arrival, multiple machine breakdowns, and multiple job arrivals demonstrate that the proposed hybrid algorithm with the rescheduling strategy achieves significant improvement and the proposed method obtains the best new solution, resulting in a significant decrease in makespan. Full article
37 pages, 1429 KiB  
Review
A Critical Analysis of Quadratic Boost Based High-Gain Converters for Electric Vehicle Applications: A Review
by Madhav Kumar, Kaibalya Prasad Panda, Ramasamy T. Naayagi, Ritula Thakur and Gayadhar Panda
Sensors 2024, 24(7), 2186; https://doi.org/10.3390/s24072186 (registering DOI) - 28 Mar 2024
Abstract
Conventional DC-DC boost converters have played a vital role in electric vehicle (EVs) powertrains by enabling the necessary voltage to increase to meet the needs of electric motors. However, recent developments in high-gain converters have introduced new possibilities with enhanced voltage amplification capabilities [...] Read more.
Conventional DC-DC boost converters have played a vital role in electric vehicle (EVs) powertrains by enabling the necessary voltage to increase to meet the needs of electric motors. However, recent developments in high-gain converters have introduced new possibilities with enhanced voltage amplification capabilities and efficiency. This study discusses and evaluates the state-of-the-art high-gain DC-DC converters for EV applications based on the Quadratic Boost Converter (QBC). Research into innovative topologies has increased in response to the increasing demand for efficient and high-performance power electronic converters in the rapidly expanding EV industry. Due to its ability to provide more significant voltage gains than conventional boost converters, the QBC has become a viable option for meeting the unique requirements of EV power systems. This survey focuses on the efficiency, power density, and overall performance parameters of QBC-based high-gain converters. The literature review provides a foundation for comprehending power electronics converters’ trends, challenges, and opportunities. The acquired knowledge can enhance the design and optimization of high-gain converters based on the QBC, thereby fostering more sustainable and efficient power systems for the expanding electric mobility industry. In the future, the report suggests that investigating new high-gain converter design methodologies will reduce component stress and enhance the intact system efficiency. Full article
(This article belongs to the Section Sensor Networks)
11 pages, 332 KiB  
Article
Bullying at School, Cyberbullying, and Loneliness: National Representative Study of Adolescents in Denmark
by Katrine Rich Madsen, Mogens Trab Damsgaard, Kimberly Petersen, Pamela Qualter and Bj?rn E. Holstein
Int. J. Environ. Res. Public Health 2024, 21(4), 414; https://doi.org/10.3390/ijerph21040414 (registering DOI) - 28 Mar 2024
Abstract
Aims: The aim was to examine how loneliness was associated with bullying victimization at school and online. Methods: We used data from the Danish arm of the international Health Behavior in School-aged Children (HBSC) study from 2022. The study population was a nationally [...] Read more.
Aims: The aim was to examine how loneliness was associated with bullying victimization at school and online. Methods: We used data from the Danish arm of the international Health Behavior in School-aged Children (HBSC) study from 2022. The study population was a nationally representative sample of 11–15-year-olds who completed the internationally standardized HBSC questionnaire at school, n = 5382. Multilevel logistic regression was applied to study the associations between bullying victimization and loneliness. Results: The prevalence of reporting loneliness often or very often was 9.0%; 6.3% of the sample experienced habitual bullying victimization at school, and 4.8% incurred cyberbullying. There was a strong and graded association between loneliness and bullying victimization at school and cyberbullying. The associations were significant for boys and girls, and the association between exposure to bullying at school and loneliness was steeper for boys than girls. The gradients were steeper for physical bullying than for cyberbullying. Students exposed to habitual bullying in both contexts had an adjusted OR (95% CI) of 11.21 (6.99–17.98) for loneliness. Conclusion: Exposure to bullying at school and cyberbullying are strongly associated with loneliness. It is important to reduce bullying at school and on the internet and to promote effective interventions to reduce continuing loneliness. Full article
11 pages, 251 KiB  
Review
Proton Pump Inhibitors and Cancer Risk: A Comprehensive Review of Epidemiological and Mechanistic Evidence
by Ibrahim O. Sawaid and Abraham O. Samson
J. Clin. Med. 2024, 13(7), 1970; https://doi.org/10.3390/jcm13071970 (registering DOI) - 28 Mar 2024
Abstract
Background: Proton pump inhibitors (PPIs) are commonly prescribed long-acting drugs used to treat acid reflux, gastroesophageal reflux disease (GERD), and peptic ulcers. Recently, concerns have been raised about their safety, particularly due to the association between long-term PPI use and cancer development. Multiple [...] Read more.
Background: Proton pump inhibitors (PPIs) are commonly prescribed long-acting drugs used to treat acid reflux, gastroesophageal reflux disease (GERD), and peptic ulcers. Recently, concerns have been raised about their safety, particularly due to the association between long-term PPI use and cancer development. Multiple comprehensive studies have consistently suggested a noteworthy link between prolonged PPI usage and an increased risk of developing gastric, esophageal, colorectal, and pancreatic cancers, yet the precise underlying mechanism remains elusive. Methods: First, we review the extensive body of research that investigates the intricate relationship between cancer and PPIs. Then, we predict PPI toxicity using the prodrug structures with the ProTox-II webserver. Finally, we predict the relative risk of cancer for each PPI, using PubMed citation counts of each drug and keywords related to cancer. Results: Our review indicates that prolonged PPI use (exceeding three months) is significantly associated with an elevated risk of cancer, while shorter-term usage (less than three months) appears to pose a comparatively lower risk. Our review encompasses various proposed mechanisms, such as pH and microbiome alterations, vitamin and mineral malabsorption, hypergastrinemia, and enterochromaffin-like cell proliferation, while ProTox-II also suggests aryl hydrocarbon receptor binding. Potentially, the PubMed citations count suggests that the PPIs omeprazole and lansoprazole are more associated with cancer than pantoprazole and esomeprazole. In comparison, the H2R blocker, famotidine, is potentially less associated with cancer than PPIs, and may serve as a safer alternative treatment for periods beyond 3 months. Conclusions: Despite the well-established cancer risk associated with PPIs, it is notable that these medications continue to be widely prescribed for periods longer than 3 months. Thus, it is of paramount importance for clinicians and patients to thoughtfully evaluate the potential risks and benefits of long-term PPI usage and explore alternative treatments before making informed decisions regarding their medical management. Full article
(This article belongs to the Section Oncology)
19 pages, 2902 KiB  
Article
The Design and Optimization of a Novel Hybrid Excitation Generator for Vehicles
by Jianwei Ma, Fengyi Gu, Liwei Wang, Shilun Ma, Amir-Mohammad Golmohammadi and Shaohang Zhang
World Electr. Veh. J. 2024, 15(4), 139; https://doi.org/10.3390/wevj15040139 (registering DOI) - 28 Mar 2024
Abstract
Silicon rectifier generators, which are single-excitation generators, are commonly used in vehicles. However, a traditional single-excitation generator cannot satisfy the requirements of modern vehicles due to its low efficiency, high failure rate and large excitation loss; a hybrid excitation generator is more suitable [...] Read more.
Silicon rectifier generators, which are single-excitation generators, are commonly used in vehicles. However, a traditional single-excitation generator cannot satisfy the requirements of modern vehicles due to its low efficiency, high failure rate and large excitation loss; a hybrid excitation generator is more suitable for a wide range of applications in vehicles because of its many advantages. In this study, a novel, high-efficiency and energy-saving hybrid excitation generator with a claw-pole series magnetic circuit for vehicles was designed. The magnetic circuit and principle of operation were analyzed. The structure parameters of the hybrid excitation generator were initially designed according to motor design theory. The model of the hybrid excitation generator was built based on the finite element method, and the no-load characteristic was analyzed. Furthermore, the influences of the permanent magnet thickness and core slot width on the performance of the generator were analyzed. According to the results, the structural parameters were optimized. The no-load output characteristics and load characteristics were compared between the generator and a silicon rectifier generator, and the test results show that the design, simulation and optimization methods were reasonable. This provides theoretical support and research methods for the development of a hybrid excitation generator. Full article
14 pages, 6591 KiB  
Article
Stochastic Optimization of an Electric Bus Dynamic Wireless Charging System
by Xingzheng Zhu, Hua Fan, Shiyao Zhang and Jiao Du
World Electr. Veh. J. 2024, 15(4), 137; https://doi.org/10.3390/wevj15040137 (registering DOI) - 28 Mar 2024
Abstract
The Electric Bus Dynamic Wireless Charging (EB-DWC) system is a bus charging system that enables electric buses to receive power wirelessly from ground-based electromagnetic induction devices. In this system, how to optimally configure the charging infrastructures while considering the unpredictable nature of bus [...] Read more.
The Electric Bus Dynamic Wireless Charging (EB-DWC) system is a bus charging system that enables electric buses to receive power wirelessly from ground-based electromagnetic induction devices. In this system, how to optimally configure the charging infrastructures while considering the unpredictable nature of bus movement is a great challenge. This paper presents an optimization problem for an EB-DWC system in urban settings, addressing stochastic elements inherent in the vehicle speed, initial charging state, and dwell time at bus stops. We formulate a stochastic planning problem for the EB-DWC system by integrating these uncertainties and apply Monte Carlo sampling techniques to effectively solve this problem. The proposed method can improve the system’s robustness effectively. Full article
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25 pages, 370 KiB  
Article
The Existence Results of Solutions to the Nonlinear Coupled System of Hilfer Fractional Differential Equations and Inclusions
by Renhao Ma, Yuan Meng and Huihui Pang
Fractal Fract. 2024, 8(4), 194; https://doi.org/10.3390/fractalfract8040194 (registering DOI) - 28 Mar 2024
Abstract
This paper is dedicated to studying the existence results of solutions to the nonlinear coupled system of Hilfer fractional differential equations and inclusions, with multi-strip and multi-point mixed boundary conditions. Through tools such as the Leray-Schauder alternative and the nonlinear alternative of Leray-Schauder [...] Read more.
This paper is dedicated to studying the existence results of solutions to the nonlinear coupled system of Hilfer fractional differential equations and inclusions, with multi-strip and multi-point mixed boundary conditions. Through tools such as the Leray-Schauder alternative and the nonlinear alternative of Leray-Schauder type, continuous and measurable selection theorems, along with Leray-Schauder degree theory, the main results can be obtained. The Hilfer fractional differential system has practical implications for specific physical phenomena. Examples are provided to clarify the application of our main results. Full article
12 pages, 8558 KiB  
Article
Probabilistic Forecasting of Lightning Strikes over the Continental USA and Alaska: Model Development and Verification
by Ned Nikolov, Phillip Bothwell and John Snook
Fire 2024, 7(4), 111; https://doi.org/10.3390/fire7040111 (registering DOI) - 28 Mar 2024
Abstract
Lightning is responsible for the most area annually burned by wildfires in the extratropical region of the Northern Hemisphere. Hence, predicting the occurrence of wildfires requires reliable forecasting of the chance of cloud-to-ground lightning strikes during storms. Here, we describe the development and [...] Read more.
Lightning is responsible for the most area annually burned by wildfires in the extratropical region of the Northern Hemisphere. Hence, predicting the occurrence of wildfires requires reliable forecasting of the chance of cloud-to-ground lightning strikes during storms. Here, we describe the development and verification of a probabilistic lightning-strike algorithm running on a uniform 20 km grid over the continental USA and Alaska. This is the first and only high-resolution lightning forecasting model for North America derived from 29-year-long data records. The algorithm consists of a large set of regional logistic equations parameterized on the long-term data records of observed lightning strikes and meteorological reanalysis fields from NOAA. Principal Component Analysis was employed to extract 13 principal components from a list of 611 potential predictors. Our analysis revealed that the occurrence of cloud-to-ground lightning strikes primarily depends on three factors: the temperature and geopotential heights across vertical pressure levels, the amount of low-level atmospheric moisture, and wind vectors. These physical variables isolate the conditions that are favorable for the development of thunderstorms and impact the vertical separation of electric charges in the lower troposphere during storms, which causes the voltage potential between the ground and the cloud deck to increase to a level that triggers electrical discharges. The results from a forecast verification using independent data showed excellent model performance, thus making this algorithm suitable for incorporation into models designed to forecast the chance of wildfire ignitions. Full article
(This article belongs to the Special Issue Probabilistic Risk Assessments in Fire Protection Engineering)
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24 pages, 5732 KiB  
Article
Design of a Modularization-Based Automation Performance Simulation Framework for Multi-Vehicle Interaction System
by Qifeng Qian, Ronghui Xiang, Xiaohua Zeng, Dafeng Song and Xuanming Zhang
World Electr. Veh. J. 2024, 15(4), 138; https://doi.org/10.3390/wevj15040138 (registering DOI) - 28 Mar 2024
Abstract
With the electrification and connectivity of vehicles in transportation, traditional vehicles with single drivetrains are being replaced by pure electric or hybrid electric vehicles (HEVs). This evolution has given rise to diverse electromechanical coupling drivetrains. There is a pressing need to update simulation [...] Read more.
With the electrification and connectivity of vehicles in transportation, traditional vehicles with single drivetrains are being replaced by pure electric or hybrid electric vehicles (HEVs). This evolution has given rise to diverse electromechanical coupling drivetrains. There is a pressing need to update simulation software to assess the economic performance of vehicles in various environments, and promote sustainable development and energy conservation. This paper presents a unified framework for the construction and automated operation of large-scale automated vehicle simulations with multiple drivetrain types, facilitating synchronous information exchange among vehicles. Central to the framework is the development of a plug-and-play vehicle model based on a modular component design, facilitating the rapid assembly of vehicles with varied drivetrain configurations and standardizing simulation file management. Additionally, a standardized simulation process construction is established to accommodate the automated operation of simulations. Furthermore, a data scheduling method among vehicles is introduced to achieve multi-vehicle interconnection simulation. Finally, the effectiveness of the framework is demonstrated through a case study involving queue-following control for HEVs. This framework aims to provide a comprehensive solution for quickly establishing automated simulation environments for multi-vehicle interaction, enhancing model reusability and scalability. Full article
(This article belongs to the Topic Advanced Electric Vehicle Technology, 2nd Volume)
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22 pages, 528 KiB  
Article
A Quasilinearization Approach for Identification Control Vectors in Fractional-Order Nonlinear Systems
by Miglena N. Koleva and Lubin G. Vulkov
Fractal Fract. 2024, 8(4), 196; https://doi.org/10.3390/fractalfract8040196 (registering DOI) - 28 Mar 2024
Abstract
This paper is concerned with solving the problem of identifying the control vector problem for a fractional multi-order system of nonlinear ordinary differential equations (ODEs). We describe a quasilinearization approach, based on minimization of a quadratic functional, to compute the values of the [...] Read more.
This paper is concerned with solving the problem of identifying the control vector problem for a fractional multi-order system of nonlinear ordinary differential equations (ODEs). We describe a quasilinearization approach, based on minimization of a quadratic functional, to compute the values of the unknown parameter vector. Numerical algorithm combining the method with appropriate fractional derivative approximation on graded mesh is applied to SIS and SEIR problems to illustrate the efficiency and accuracy. Tikhonov regularization is implemented to improve the convergence. Results from computations, both with noisy-free and noisy data, are provided and discussed. Simulations with real data are also performed. Full article
(This article belongs to the Special Issue Fractional Order Controllers for Non-linear Systems)
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18 pages, 2463 KiB  
Article
Research on Vision-Based Servoing and Trajectory Prediction Strategy for Capturing Illegal Drones
by Jinyu Ma, Puhui Chen, Xinhan Xiong, Liangcheng Zhang, Shengdong Yu and Dongyuan Zhang
Drones 2024, 8(4), 127; https://doi.org/10.3390/drones8040127 (registering DOI) - 28 Mar 2024
Abstract
A proposed strategy for managing airspace and preventing illegal drones from compromising security involves the use of autonomous drones equipped with three key functionalities. Firstly, the implementation of YOLO-v5 technology allows for the identification of illegal drones and the establishment of a visual-servo [...] Read more.
A proposed strategy for managing airspace and preventing illegal drones from compromising security involves the use of autonomous drones equipped with three key functionalities. Firstly, the implementation of YOLO-v5 technology allows for the identification of illegal drones and the establishment of a visual-servo system to determine their relative position to the autonomous drone. Secondly, an extended Kalman filter algorithm predicts the flight trajectory of illegal drones, enabling the autonomous drone to compensate in advance and significantly enhance the capture success rate. Lastly, to ensure system robustness and suppress interference from illegal drones, an adaptive fast nonsingular terminal sliding mode technique is employed. This technique achieves finite time convergence of the system state and utilizes delay estimation technology for the real-time compensation of unknown disturbances. The stability of the closed-loop system is confirmed through Lyapunov theory, and a model-based hardware-in-the-loop simulation strategy is adopted to streamline system development and improve efficiency. Experimental results demonstrate that the designed autonomous drone accurately predicts the trajectory of illegal drones, effectively captures them using a robotic arm, and maintains stable flight throughout the process. Full article
14 pages, 5758 KiB  
Article
Glass Beads Test with True Triaxial Stress Path Achieved by Conventional Triaxial Apparatus
by Xuefeng Li, Jiahui Ma and Longlong Lv
Fractal Fract. 2024, 8(4), 193; https://doi.org/10.3390/fractalfract8040193 (registering DOI) - 28 Mar 2024
Abstract
The impact of fabric anisotropy, fractal dimension, and breakage on the strength and deformation of granular materials were diminished by uniform-size spherical glass beads. Triaxial drained and undrained tests were performed on glass beads based on a novel method to substitute true triaxial [...] Read more.
The impact of fabric anisotropy, fractal dimension, and breakage on the strength and deformation of granular materials were diminished by uniform-size spherical glass beads. Triaxial drained and undrained tests were performed on glass beads based on a novel method to substitute true triaxial stress paths with conventional triaxial apparatus equivalents with varying intermediate principal stress coefficients (b-values). The result indicates that all specimens manifested a noticeable strain-softening phenomenon. The peak strength decreased with increasing b-value, and the specimens showed more pronounced dilatancy. This pattern is similar to the results of the true triaxial test in current research. Compared to the undrained test, the peak friction angle in the drained test displayed a greater variation with varying b-values, which indicated that the mechanical response of glass beads is sensitive to water. This difference provides experimental evidence for comprehending effective stress in granular materials with constant friction coefficients. The experiments reflect the effect of b-value changes on the p-q stress path, as well as on the peak stress ratio, the state transition stress ratio, and the critical state stress ratio. The specimens exhibited a distinct shear band at different b-values ranging from 0.2 to 0.6, which is different from observations in conventional triaxial tests for granular materials. Full article
(This article belongs to the Special Issue Fractal Mechanics of Engineering Materials)
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34 pages, 495 KiB  
Article
Fundamental Matrix, Integral Representation and Stability Analysis of the Solutions of Neutral Fractional Systems with Derivatives in the Riemann—Liouville Sense
by Hristo Kiskinov, Mariyan Milev, Slav Ivanov Cholakov and Andrey Zahariev
Fractal Fract. 2024, 8(4), 195; https://doi.org/10.3390/fractalfract8040195 (registering DOI) - 28 Mar 2024
Abstract
The paper studies a class of nonlinear disturbed neutral linear fractional systems with derivatives in the the Riemann–Liouville sense and distributed delays. First, it is proved that the initial problem for these systems with discontinuous initial functions under some natural assumptions possesses a [...] Read more.
The paper studies a class of nonlinear disturbed neutral linear fractional systems with derivatives in the the Riemann–Liouville sense and distributed delays. First, it is proved that the initial problem for these systems with discontinuous initial functions under some natural assumptions possesses a unique solution. The assumptions used for the proof are similar to those used in the case of systems with first-order derivatives. Then, with the obtained result, we derive the existence and uniqueness of a fundamental matrix and a generalized fundamental matrix for the homogeneous system. In the linear case, via these fundamental matrices we obtain integral representations of the solutions of the homogeneous system and the corresponding inhomogeneous system. Furthermore, for the fractional systems with Riemann–Liouville derivatives we introduce a new concept for weighted stabilities in the Lyapunov, Ulam–Hyers, and Ulam–Hyers–Rassias senses, which coincides with the classical stability concepts for the cases of integer-order or Caputo-type derivatives. It is proved that the zero solution of the homogeneous system is weighted stable if and only if all its solutions are weighted bounded. In addition, for the homogeneous system it is established that the weighted stability in the Lyapunov and Ulam–Hyers senses are equivalent if and only if the inequality appearing in the Ulam–Hyers definition possess only bounded solutions. Finally, we derive natural sufficient conditions under which the property of weighted global asymptotic stability of the zero solution of the homogeneous system is preserved under nonlinear disturbances. Full article
(This article belongs to the Special Issue Advances in Fractional Modeling and Computation)
18 pages, 1342 KiB  
Article
MiR-106a-5p by Targeting MAP3K2 Promotes Repair of Oxidative Stress Damage to the Intestinal Barrier in Prelaying Ducks
by Li Zhang, Xiang Luo, Rui Tang, Yan Wu, Zhenhua Liang, Jingbo Liu, Jinsong Pi and Hao Zhang
Animals 2024, 14(7), 1037; https://doi.org/10.3390/ani14071037 (registering DOI) - 28 Mar 2024
Abstract
Under caged stress conditions, severe disruptions in duck intestinal barrier function, which adversely affect economic performance, have been observed. MiRNAs play a crucial role in cellular processes, but the mechanisms underlying their involvement in repairing oxidative stress-induced damage to duck intestinal barriers have [...] Read more.
Under caged stress conditions, severe disruptions in duck intestinal barrier function, which adversely affect economic performance, have been observed. MiRNAs play a crucial role in cellular processes, but the mechanisms underlying their involvement in repairing oxidative stress-induced damage to duck intestinal barriers have not been elucidated. We performed miRNA-seq and protein tandem mass tagging (TMT) sequencing and identified differentially expressed miRNAs and proteins in oxidative stress-treated ducks. Dual-luciferase reporter vector experiments, RT‒qPCR, and Western blotting revealed the regulatory role of apla-miR-106a-5p/MAP3K2 in intestinal barrier damage repair. The results showed that oxidative stress led to shortened villi and deepened crypts, impairing intestinal immune function. Significant downregulation of apla-miR-106a-5p was revealed by miRNA-seq, and the inhibition of its expression not only enhanced cell viability but also improved intestinal barrier function. TMT protein sequencing revealed MAP3K2 upregulation in caged-stressed duck intestines, and software analysis confirmed MAP3K2 as the target gene of apla-miR-106a-5p. Dual-fluorescence reporter gene experiments demonstrated direct targeting of MAP3K2 by apla-miR-106a-5p. RT‒qPCR showed no effect on MAP3K2 expression, while Western blot analysis indicated that MAP3K2 protein expression was suppressed. In summary, apla-miR-106a-5p targets MAP3K2, regulating gene expression at the transcriptional level and facilitating effective repair of intestinal barrier damage. This discovery provides new insights into the molecular mechanisms of physiological damage in ducks under caged stress, offering valuable guidance for related research. Full article
(This article belongs to the Special Issue Redox Balance in Animal Physiology: Health and Welfare)
19 pages, 1763 KiB  
Article
Estimating Lung Volume Capacity from X-ray Images Using Deep Learning
by Samip Ghimire and Santosh Subedi
Quantum Beam Sci. 2024, 8(2), 11; https://doi.org/10.3390/qubs8020011 (registering DOI) - 28 Mar 2024
Abstract
Estimating lung volume capacity is crucial in clinical medicine, especially in disease diagnostics. However, the existing estimation methods are complex and expensive, which require experts to handle and consequently are more error-prone and time-consuming. Thus, developing an automatic measurement system without a human [...] Read more.
Estimating lung volume capacity is crucial in clinical medicine, especially in disease diagnostics. However, the existing estimation methods are complex and expensive, which require experts to handle and consequently are more error-prone and time-consuming. Thus, developing an automatic measurement system without a human operator that is less prone to human error and, thus, more accurate has always been a prerequisite. The limitation of radiation dose and various medical conditions in technologies like computed tomography was also the primary concern in the past. Although qualitative prediction of lung volume may be a trivial task, designing clinically relevant and automated methods that effectively incorporate imaging data is a challenging problem. This paper proposes a novel multi-tasking-based automatic lung volume estimation method using deep learning that jointly learns segmentation and regression of volume estimation. The two networks, namely, segmentation and regression networks, are sequentially operated with some shared layers. The segmentation network segments the X-ray images, whose output is regressed by the regression network to determine the final lung volume. Besides, the dataset used in the proposed method is collected from three different secondary sources. The experimental results show that the proposed multi-tasking approach performs better than the individual networks. Further analysis of the multi-tasking approach with two different networks, namely, UNet and HRNet, shows that the network with HRNet performs better than the network with UNet with less volume estimation mean square error of 0.0010. Full article
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28 pages, 26981 KiB  
Article
Micro- and Macro-Scale Topology Optimization of Multi-Material Functionally Graded Lattice Structures
by Jerónimo Santos, Abdolrasoul Sohouli and Afzal Suleman
J. Compos. Sci. 2024, 8(4), 124; https://doi.org/10.3390/jcs8040124 (registering DOI) - 28 Mar 2024
Abstract
Lattice structures are becoming an increasingly attractive design approach for the most diverse engineering applications. This increase in popularity is mainly due to their high specific strength and stiffness, considerable heat dissipation, and relatively light weight, among many other advantages. Additive manufacturing techniques [...] Read more.
Lattice structures are becoming an increasingly attractive design approach for the most diverse engineering applications. This increase in popularity is mainly due to their high specific strength and stiffness, considerable heat dissipation, and relatively light weight, among many other advantages. Additive manufacturing techniques have made it possible to achieve greater flexibility and resolution, enabling more complex and better-performing lattice structures. Unrestricted material unit cell designs are often associated with high computational power and connectivity problems, and highly restricted lattice unit cell designs may not reach the optimal desired properties despite their lower computational cost. This work focuses on increasing the flexibility of a restricted unit cell design while achieving a lower computational cost. It is based on a two-scale concurrent optimization of the lattice structure, which involves simultaneously optimizing the topology at both the macro- and micro-scales to achieve an optimal topology. To ensure a continuous optimization approach, surrogate models are used to define material and geometrical properties. The elasticity tensors for a lattice unit cell are obtained using an energy-based homogenization method combined with voxelization. A multi-variable parameterization of the material unit cell is defined to allow for the synthesis of functionally graded lattice structures. Full article
(This article belongs to the Special Issue Characterization and Modelling of Composites, Volume III)
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14 pages, 1297 KiB  
Article
Assessment of Sequential Yeast Inoculation for Blackcurrant Wine Fermentation
by Zhuoyu Wang, Andrej Svyantek, Zachariah Miller and Aude A. Watrelot
Fermentation 2024, 10(4), 184; https://doi.org/10.3390/fermentation10040184 (registering DOI) - 28 Mar 2024
Abstract
Blackcurrant is well known for its health benefits, but its wine products are understudied. In this research, studies were conducted after non-Saccharomyces and Saccharomyces yeast strain inoculation in less than 20% (w/v) fruit must for blackcurrant fermentation. Three [...] Read more.
Blackcurrant is well known for its health benefits, but its wine products are understudied. In this research, studies were conducted after non-Saccharomyces and Saccharomyces yeast strain inoculation in less than 20% (w/v) fruit must for blackcurrant fermentation. Three inoculations were carried out on blackcurrant musts, as follows: (1) sequential inoculation with Torulaspora delbrueckii (strain Biodiva) followed by Saccharomyces EC1118 strain; (2) sequential inoculation with Metschnikowia pulcherimma (strain Flavia) followed by EC1118; (3) single-strain inoculation with EC1118 as the control treatment. None of these treatments did alter sugar consumption dynamics. Biodiva inoculation had impacts on both color dynamic parameter changes and final wine color profiles compared to EC1118. The final wine compositions indicate that Biodiva treatment had a significant impact on wine pH and acidity, whereas EC1118 single-strain largely influenced wine ethanol and glycerol contents. Although the total antioxidant capabilities were close among the three produced wines, the monophenol profiles indicate that Biodiva enhanced the total anthocyanin and hydroxycinnamates content but reduced the total flavanol contents in the final wine. EC1118 and Flavia wines contained more total flavanols compared to Biodiva treatment. The nonflavonoid profiles indicate that there were no significant differences among the three treatments. Our findings provide useful information for the application of yeast strains in blackcurrant wine fermentation. Full article
(This article belongs to the Section Fermentation for Food and Beverages)
19 pages, 2115 KiB  
Article
Metagenomic/Metaproteomic Investigation of the Microbiota in Dongbei Suaicai, a Traditional Fermented Chinese Cabbage
by Yamin Zhang, Haiyang Yan, Xiangxiu Xu, Xiaowei Xiao, Yuan Yuan, Na Guo, Tiehua Zhang, Mengyao Li, Ling Zhu, Changhui Zhao, Zuozhao Wang and Haiqing Ye
Fermentation 2024, 10(4), 185; https://doi.org/10.3390/fermentation10040185 (registering DOI) - 28 Mar 2024
Abstract
Dongbei Suaicai (DBSC) has a complicated microbial ecosystem in which the composition and metabolism of microbial communities during the process have not been well explored. Here, combined metagenomic and metaproteomic technology was used to reveal the taxonomic and metabolic profiles of DBSC. The [...] Read more.
Dongbei Suaicai (DBSC) has a complicated microbial ecosystem in which the composition and metabolism of microbial communities during the process have not been well explored. Here, combined metagenomic and metaproteomic technology was used to reveal the taxonomic and metabolic profiles of DBSC. The results showed that firmicutes and proteobacteria were the prevalent bacteria in phylum and Pseudomonas, while Weissella, Pediococcus, and Leuconostoc were the prevalent genus. The vital metabolic pathways were involved in glycolysis/gluconeogenesis [path: ko00010], as well as pyruvate metabolism [path: ko00620], fructose and mannose metabolism [path: Ko00051], glycine, and serine and threonine metabolism [path: Ko00260]. Moreover, the key proteins (dps, fliC, tsf, fusA, atpD, metQ, pgi, tpiA, eno, alaS, bglA, tktA, gor, pdhD, aceE, and gnd) in related metabolized pathways were enriched during fermentation. This study will aid in facilitating the understanding of the fermentation mechanisms of DBSC. Full article
(This article belongs to the Section Fermentation for Food and Beverages)
15 pages, 1241 KiB  
Article
Vocalization Pattern and Echolocation Signal Characteristics of Yangtze Finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) in Captivity
by Jia Chen, Haiying Liang, Danqing Lin, Jialu Zhang, Dong Li, Kun Ye, Wenfei Lu and Kai Liu
Fishes 2024, 9(4), 119; https://doi.org/10.3390/fishes9040119 (registering DOI) - 28 Mar 2024
Abstract
The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP) possesses the ability to detect distance through echolocation signals, and its sonar signal signature is adjusted to detect different targets. In order to understand the vocal characteristics of YFPs in different behavioral states [...] Read more.
The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP) possesses the ability to detect distance through echolocation signals, and its sonar signal signature is adjusted to detect different targets. In order to understand the vocal characteristics of YFPs in different behavioral states and their differential performance, we recorded the vocal activities of YFPs in captivity during free-swimming, feeding, and nighttime resting and quantified their signal characteristic parameters for statistical analysis and comparison. The results showed that the number of vocalizations of the YFPs in the daytime free-swimming state was lower than that in the feeding and nighttime resting states, and the echolocation signals emitted in these three states showed significant differences in the −10 dB duration, −3 dB bandwidth, −10 dB bandwidth, and root-mean-square (RMS) bandwidth. Analysis of the resolution of the echolocation signals of the YFPs using the ambiguity function indicated that their distance resolution could reach the millimeter level. These results indicate that the echolocation signal characteristics of YFPs present diurnal differences and that they can be adjusted with changes in their detection targets. The results of this study can provide certain scientific references and foundations for the studies of tooth whale behavioral acoustics, and provide relevant scientific guidance for the conservation and management of YFPs. Full article
(This article belongs to the Special Issue Underwater Acoustic Technologies for Sustainable Fisheries)
22 pages, 2300 KiB  
Review
Yeast Bioflavoring in Beer: Complexity Decoded and Built up Again
by Chiara Nasuti and Lisa Solieri
Fermentation 2024, 10(4), 183; https://doi.org/10.3390/fermentation10040183 (registering DOI) - 28 Mar 2024
Abstract
Yeast is a powerful bioflavoring platform, suitable to confer special character and complexity to beer aroma. Enhancing yeast bioflavoring represents a chance for the brewing production chain to diversify its product portfolio and to increase environmental sustainability in the era of climate change. [...] Read more.
Yeast is a powerful bioflavoring platform, suitable to confer special character and complexity to beer aroma. Enhancing yeast bioflavoring represents a chance for the brewing production chain to diversify its product portfolio and to increase environmental sustainability in the era of climate change. In flavor compound metabolism, multiple genes encoding biosynthetic enzymes and the related regulatory factors are still poorly known, but significant advances have been recently made to dissect gene contribution in flavor molecule production. Furthermore, causative mutations responsible for the huge strain diversity in yeast bioflavoring aptitude have been recently disclosed. This review covers the most recent advances in the genetics of yeast bioflavoring, with special regards to higher alcohols, esters, monoterpene alcohols, thiols, and phenolic derivatives of hydroxycinnamic acids. We also critically discussed the most significant strategies to enhance yeast bioflavoring, including bioprospecting for novel Saccharomyces and non-Saccharomyces strains, whole-genome engineering, and metabolic engineering. Full article
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17 pages, 4983 KiB  
Article
HiFly-Dragon: A Dragonfly Inspired Flapping Flying Robot with Modified, Resonant, Direct-Driven Flapping Mechanisms
by He Ma, Peiyi Gong, Yuqiang Tian, Qingnan Wu, Min Pan, Hao Yin, Youjiang Liu and Chilai Chen
Drones 2024, 8(4), 126; https://doi.org/10.3390/drones8040126 (registering DOI) - 28 Mar 2024
Abstract
This paper describes a dragonfly-inspired Flapping Wing Micro Air Vehicle (FW-MAV), named HiFly-Dragon. Dragonflies exhibit exceptional flight performance in nature, surpassing most of the other insects, and benefit from their abilities to independently move each of their four wings, including adjusting the flapping [...] Read more.
This paper describes a dragonfly-inspired Flapping Wing Micro Air Vehicle (FW-MAV), named HiFly-Dragon. Dragonflies exhibit exceptional flight performance in nature, surpassing most of the other insects, and benefit from their abilities to independently move each of their four wings, including adjusting the flapping amplitude and the flapping amplitude offset. However, designing and fabricating a flapping robot with multi-degree-of-freedom (multi-DOF) flapping driving mechanisms under stringent size, weight, and power (SWaP) constraints poses a significant challenge. In this work, we propose a compact microrobot dragonfly with four tandem independently controllable wings, which is directly driven by four modified resonant flapping mechanisms integrated on the Printed Circuit Boards (PCBs) of the avionics. The proposed resonant flapping mechanism was tested to be able to enduringly generate 10 gf lift at a frequency of 28 Hz and an amplitude of 180° for a single wing with an external DC power supply, demonstrating the effectiveness of the resonance and durability improvement. All of the mechanical parts were integrated on two PCBs, and the robot demonstrates a substantial weight reduction. The latest prototype has a wingspan of 180 mm, a total mass of 32.97 g, and a total lift of 34 gf. The prototype achieved lifting off on a balance beam, demonstrating that the directly driven robot dragonfly is capable of overcoming self-gravity with onboard batteries. Full article
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16 pages, 10953 KiB  
Article
Detection and Comparison of Volatile Organic Compounds in Four Varieties of Hawthorn Using HS-GC-IMS
by Lijun Zhu, Feilin Ou, Yun Xiang, Bin Wang, Yingchao Mao, Lingfeng Zhu, Qun Zhang and Chang Lei
Separations 2024, 11(4), 100; https://doi.org/10.3390/separations11040100 (registering DOI) - 28 Mar 2024
Abstract
Hawthorn is a type of natural food with significant medicinal and nutritional properties; it has been listed in the “Both Food and Drug” list by the Chinese Ministry of Health Item List since 1997. However, hawthorn varieties have complex origins, and there are [...] Read more.
Hawthorn is a type of natural food with significant medicinal and nutritional properties; it has been listed in the “Both Food and Drug” list by the Chinese Ministry of Health Item List since 1997. However, hawthorn varieties have complex origins, and there are significant differences in the content, type, and medicinal efficacy of the chemically active ingredients in different varieties of hawthorn. This leads to the phenomenon of mixed varieties and substandard products being passed off as high-quality. In this work, by using headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS), we identified and analyzed volatile organic compounds (VOCs) in four varieties of hawthorn, establishing their characteristic fingerprints. As a result, a total of 153 peaks were detected, and 139 VOCs were also identified. As shown by the fingerprint profiles, the different hawthorn samples contained different VOCs. Meanwhile, by using principal component analysis (PCA), Euclidean distance, and partial least-squares discriminant analysis (PLS-DA), the relationship between the VOCs found in the different varieties of hawthorn was revealed. This study developed a simple, fast, accurate, and sensitive method for identifying, tracking, and evaluating hawthorn varieties. Full article
(This article belongs to the Topic Advances in Analysis of Food and Beverages)
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