bluuebunny/crossref_metadata_2025 huggingface dataset:
Source and health risks of trace metals in Clarias batrachus and Chrysichthys nigrodigitatus from surface waters in Bayelsa State, Nigeria: a probabilistic model
Authors: Izah Sylvester Chibueze , Richard Glory , Stanley Herbert Okechukwu , Sawyer Wisdom Ebiye , Uwaeme Onyebuchi Remy , Sylva Ligeiaziba
Published: September 2024

Introduction

Human activities have inadvertently led to the release of harmful substances, including trace metals, into aquatic environments, with consequential impacts on aquatic organisms and potential health risks for consumers. This research assessed the presence, origins, and health implications of trace elements within the muscles of Clarias batrachus and Chrysichthys nigrodigitatus from the Bomadi and Gbotebo rivers and their surroundings in Bayelsa State, Nigeria.

Methods

Thirty samples from each fish species were collected and analyzed to conduct the study. Through the use of an atomic absorption spectrophotometer, the researchers determined the concentrations of trace metals, including iron, copper, zinc, lead, nickel, cadmium, and cobalt, in the fish tissues.

Results and discussion

The concentrations of the metals within the two fish species varied, with notable differences in zinc and cadmium levels. Utilizing statistical analyses like Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (CA), it was established that the trace metals originated from diverse sources. The study then evaluated health risks associated with these trace elements, considering both non-carcinogenic and carcinogenic hazards for different age groups. The results indicated that children’s total target hazard quotient fell below 1 for both fish species, implying a limited tendency toward non-carcinogenic risks through lifelong fish consumption. However, in some adult fish samples, the quotient exceeded 1, indicating a higher potential for non-carcinogenic risks. Regarding carcinogenic hazards, the mean risks were generally lower than the accepted threshold, except for lead in both fish species among adults and children. Stricter values highlighted that only lead concentrations in fish from both categories were deemed acceptable. Consequently, this study highlights the importance of raising awareness among consumers who buy fish from the studied region. Moreover, consistent monitoring of potentially harmful trace elements in water, sediments, and fish is recommended to safeguard consumer health and well-being.
Potential of Trichoderma strains to positively modulate plant growth processes and bulb yield in Rabi onion
Authors: Dutta Ram , Kumar Satish , Jayalakshmi K. , Radhakrishna A. , Bhagat Kiran , Manjunatha Gowda D. C. , Karuppaiah V. , Bhandari Hem Raj , Bomble Ram , Gurav Vishal , Mahajan Vijay , Singh Major
Published: September 2024

The use of beneficial microbes is hitherto known and constantly increasing in agriculture due to their positive impact on crop growth and yield, and their minimal negative impact on the environment. The objective of this study was to evaluate the impact of eight Trichoderma strains of diverse origin on crop growth and yield of onion under field conditions. The identity of the strains used in the current study was confirmed by ITS and Tef1 gene sequencing. Field experiments were conducted in the Rabi season for 2 years (2020–21, and 2022–23) to evaluate the effect of the application of eight different Trichoderma strains that were applied individually and separately as eight different treatments (T1–T8) in experimental plots. In the plant growth promotion assay conducted in vitro, all strains showed the ability to produce IAA (indole-3-acetic acid), with levels ranging from 23.52 μg/mL (T6) to 45.54 μg/mL (T3). Our results revealed that Trichoderma treated experimental plots displayed better growth indices (plant height, pseudostem diameter), RWC (Relative water content), leaf chlorophyll content, and yield-attributing features like biomass (bulb and root dry mass), bulb diameter, and harvested bulb yield compared to the untreated control plants. In terms of yield, the T2 strain exhibited the highest bulb yield consistently for both the years (2020–21 and 2022–23) followed by T3 being statistically at par with T5. Among all the evaluated Trichoderma strains, the strain T2 (OGRDT2) and T3 (GRDT1), taxonomically identified as Trichoderma longibrachiatum, registered bulb yield of 32.24 t/ha and 30.76 t/ha, respectively while T5 (GRDT3), identified as Trichoderma asperellum, registered 30.55 t/ha average yield for 2 years compared to 24.08 t/ha average yield recorded for untreated control plants with an increase of 34, 28 and 27%, respectively. Based on our findings, it is concluded that the T. longibrachiatum strains OGRDT2 (T2) and GRDT1 (T3), T. asperellum strain GRDT3 (T5) are the best inducers of the onion crop growth and yield in the Rabi season and would be explored further for its commercial application in onion farming.
Meshfree Variational-Physics-Informed Neural Networks (MF-VPINN): An Adaptive Training Strategy
Authors: Berrone Stefano , Pintore Moreno
Published: September 2024

In this paper, we introduce a Meshfree Variational-Physics-Informed Neural Network. It is a Variational-Physics-Informed Neural Network that does not require the generation of the triangulation of the entire domain and that can be trained with an adaptive set of test functions. In order to generate the test space, we exploit an a posteriori error indicator and add test functions only where the error is higher. Four training strategies are proposed and compared. Numerical results show that the accuracy is higher than the one of a Variational-Physics-Informed Neural Network trained with the same number of test functions but defined on a quasi-uniform mesh.
Study on the Vibration Reduction Effect of Piezoelectric Actuation on Flexible Tilting Pad Bearings with Different Structural Parameters
Authors: Qin Yanyan , Wang Xiaojing , Huang Guangyao , Zhang Xiaohan , Yi Shuxiang
Published: September 2024

To improve the vibration performance of oil-lubricated tilting pad bearing systems, this paper investigates the impact of different structural parameters on the vibration reduction effect of piezoelectric actuators on flexible tilting pad bearings. Four sets of flexible tilting pad bearings were designed and manufactured, including a flexible hinge tilting pad bearing and three sets of double-layer spring-supported flexible tilting pad bearings with different parameters. The radial displacement of the bearing load pad was controlled to varying degrees using a piezoelectric actuator, and semi-active control experiments were conducted on the flexible tilting pad bearings. The experimental results show that appropriately reducing the radial clearance and the stiffness of the bearing’s flexible structure can effectively suppress vibrations, enhance the vibration reduction effect of the piezoelectric actuation, and increase the stability of the bearing-rotor system. This study is of significant importance for the design of flexible tilting pad bearings and the vibration suppression of rotor systems.
Adaptive Nonsingular Fast Terminal Sliding Mode Control for Shape Memory Alloy Actuated System
Authors: Li Xiaoguang , Zhi Wenzhuo , Shi Enming , Fan Xiaoliang , Zhao Ming , Zhang Bi
Published: September 2024

Due to its high power-to-weight ratio, low weight, and silent operation, shape memory alloy (SMA) is widely used as a muscle-like soft actuator in intelligent bionic robot systems. However, hysteresis nonlinearity and multi-valued mapping behavior can severely impact trajectory tracking accuracy. This paper proposes an adaptive nonsingular fast terminal sliding mode control (ANFTSMC) scheme aimed at enhancing position tracking performance in SMA-actuated systems by addressing hysteresis nonlinearity, uncertain dynamics, and external disturbances. Firstly, a simplified third-order actuator model is developed and a variable gain extended state observer (VGESO) is employed to estimate unmodeled dynamics and external disturbances within finite time. Secondly, a novel nonsingular fast terminal sliding mode control (NFTSMC) law is designed to overcome singularity issues, reduce chattering, and guarantee finite-time convergence of the system states. Finally, the ANFTSMC scheme, integrating NFTSMC with VGESO, is proposed to achieve precise position tracking for the prosthetic hand. The convergence of the closed-loop control system is validated using Lyapunov’s stability theory. Experimental results demonstrate that the external pulse disturbance error of ANFTSMC is 8.19°, compared to 19.21° for the comparative method. Furthermore, the maximum absolute error for ANFTSMC is 0.63°, whereas the comparative method shows a maximum absolute error of 1.03°. These results underscore the superior performance of the proposed ANFTSMC algorithm.
A Hinge Moment Alleviation Control Strategy for Morphing Tail Aircraft Based on a Data-Driven Method
Authors: Cao Rui , Lyu Huitao
Published: September 2024

Morphing airplane technology is currently a focal point of research. For morphing airplanes, besides effective morphing strategies and control schemes, the hinge moment at the root of the vertical tail during morphing is a critical factor influencing flight safety. To prevent failure in tail morphing due to excessive hinge moments, this paper analyzes the hinge moment characteristics of the variable vertical tail structure in high-speed flight, based on a flying wing model from the China Aerodynamics Research and Development Center. The proposed adaptive morphing tail hinge moment reduction (AMTHR) method is model-free, utilizing real-time data to dynamically adjust the rudder and reduce hinge moments without requiring prior knowledge of system dynamics. This method utilizes the concept of extremum-seeking control by introducing periodic perturbations to the system and adjusting the control input based on their impact on the output. This approach drives the output toward an extremum point, enabling real-time reduction of the vertical tail hinge moment. Finally, the simulation analysis is carried out under the conditions of no wind and gust disturbance, and the effect of this method on the load reduction of the tail hinge moment is verified.
A Modified Robust Homotopic Method for the Low-Thrust Fuel-Optimal Orbital Control Problem
Authors: Huang Yuyang , Zhang Lifei , Zhang Xianjian
Published: September 2024

This study focuses on improving the application of the quadratic penalty smoothing technique for solving the fuel-optimal problem of low-thrust trajectory. Some practical techniques, including the Particle Swarm Optimization algorithm (PSO), the co-state normalization technique, and the single shooting method, are employed. These approaches can enhance convergence to the globally optimal solution. The application of PSO is improved through the introduction of the diversity termination term. Furthermore, a new parameter, the maximum thrust to initial mass ratio (CTm), is introduced and analyzed. The relationships among Lagrange multipliers for different CTm in the energy-optimal auxiliary problem are also derived. These relationships can be used in scenarios with high CTm to reduce the variable search space, leading to a significant decrease in computation time. Nonetheless, few researchers have proposed a well-defined strategy for the homotopic process. We propose a robust iteration strategy, involving the determination of the maximum step size and the distinction of sub-optimal solutions. This iterative strategy could ensure a robust convergence toward the optimal solutions. An interplanetary rendezvous example is provided to demonstrate the effectiveness of the presented techniques and strategy.
Aerodynamic Analysis and Simulation for a Z-Shaped Folding Wing UAV
Authors: Wang Jin-Gang , Guo Xiang-Ying
Published: September 2024

The potential of folding wing unmanned aerial vehicles (UAVs) in enhancing the adaptability of complex missions is substantial. Analyzing the aerodynamic characteristics of these UAVs is vital for optimizing the design of their folding wing configuration and airfoil shape. In this study, a model of a Z-shaped folding wing UAV was established with the objective of enhancing UAV maneuverability. An integrated vortex lattice method (VLM) was employed to analyze the aerodynamic characteristics of the Z-shaped folding wing and numerical simulations were utilized to validate the obtained results, which prove the effectiveness of the integrated VLM in studying aerodynamic characteristics at a high angle of attack of the Z-shaped folding wing UAV. This is a new way to reduce computation time while maintaining accuracy to calculate such complex folding structures in high fidelity. Furthermore, the Z-shaped folding wing configuration demonstrates enhanced maneuverability at high angles of attack, and a Simulink flight simulation model based on the aerodynamic coefficients of the Z-shaped folding wing verifies this property. This analysis can properly predict the post-stall characteristics for the Z-shaped folding wing UAV to ensure the safety of the vehicle during flight.
Differential Game-Based Cooperative Interception Guidance Law with Collision Avoidance
Authors: Zhu Xueping , Wang Xinxing , Li Yue , Yang Jun
Published: September 2024

To deal with the offense-defense confrontation problem of multi-missile cooperative intercepting a high-speed and large-maneuvering target, a differential game-based cooperative interception guidance law with collision avoidance is proposed, in which the offense-defense parties are the incoming target and the interceptors, respectively. Given that both offense-defense parties have uniformly decreasing speeds and first-order biproper dynamics, the relative motion models among the offense-defense parties are established, and the performance indices of the target and the interceptors are proposed. After that, the cooperative interception guidance law with collision avoidance is derived based on a differential game. The guidance law considers the effects of speed variations and rudder layouts on the motions of both offense-defense parties, ensuring excellent algorithmic real-time property and interception accuracy while introducing inter-missile collision avoidance constraints. In addition, the parameters of the target performance index are set according to the target acceleration information estimated by the interceptors. The simulation results verify the effectiveness of the guidance law designed in this paper, under various three-to-one scenarios, the interceptors could achieve collision-free interceptions with the interception accuracy of less than 5 m and the interception time difference of less than 0.1 s.
Optimization of the Camellia oleifera Fruit Harvester Engine Compartment Heat Dissipation Based on Temperature Experiments and Airflow Field Simulation
Authors: Tong Wenfu , Liao Kai , Li Lijun , Gao Zicheng , Chen Fei , Luo Hong
Published: September 2024

The Camellia oleifera fruit harvester, a specialized agricultural device, is engineered for efficient operation within the densely planted C. oleifera groves of China’s undulating terrains. Its design features a notably small footprint to navigate the constrained spaces between trees. With the enhancement of the functionality and power of the harvester, the engine compartment becomes even more congested. This, while beneficial for performance, complicates heat dissipation and reduces harvesting efficiency. In this study, experiments were initially conducted to collect temperature data from the main heat-generating components and parts susceptible to high temperatures within the harvester’s engine compartment. Subsequently, a 3D model was developed for numerical simulations, leading to the proposal of optimization schemes for the engine compartment’s structure and the validation of these schemes’ feasibility. A comparison of the experimental data, both before and after optimization, revealed a significant reduction in the surface temperatures of components within the engine compartment following optimization. As a result, the heat dissipation of the engine compartment has been greatly optimized. The harvester has demonstrated prolonged normal operation, enhancing the reliability and economy of the harvester.
Modeling for Apple-Slice Drying in Carbon Dioxide Gas
Authors: Do Tien Cong , Le Quoc Tuan , Tran Thi Thu Hang
Published: September 2024

In this study, a numerical model of a modified air-drying process of apple slices that considers the conjugate heat and mass transfer in the drying chamber is developed. Inside the apple slice sample, the continuum model is incorporated to describe the non-isothermal two-phase transport. The intra- and extra-sample heat, mass, and momentum transfer are coupled to simulate the transportation phenomena inside the drying chamber using the finite volume method implemented in computational fluid dynamic software (COMSOL Multiphysics 6.0). In this manner, temperature, velocity, moisture content of the drying agent inside the chamber, sample temperature, and moisture content distributions can be predicted. The validity of the proposed model is confirmed by a good agreement between the numerical and experimental data in terms of the overall evaporation rate and temperature. The simulation results indicate that the maldistribution of the convective heat and mass transfer resistance on the sample surface is significant. This can be explained by the nonuniform velocity distribution inside the drying chamber. Additionally, both experimental and numerical observations show that the drying process can be divided into two periods: the quasi-constant drying rate and falling drying rate periods. The impact of dryer operational conditions on the drying process is numerically investigated.
Influence of Preprocessing Methods of Automated Milking Systems Data on Prediction of Mastitis with Machine Learning Models
Authors: Kashongwe Olivier , Kabelitz Tina , Ammon Christian , Minogue Lukas , Doherr Markus , Silva Boloña Pablo , Amon Thomas , Amon Barbara
Published: September 2024

Missing data and class imbalance hinder the accurate prediction of rare events such as dairy mastitis. Resampling and imputation are employed to handle these problems. These methods are often used arbitrarily, despite their profound impact on prediction due to changes caused to the data structure. We hypothesize that their use affects the performance of ML models fitted to automated milking systems (AMSs) data for mastitis prediction. We compare three imputations—simple imputer (SI), multiple imputer (MICE) and linear interpolation (LI)—and three resampling techniques: Synthetic Minority Oversampling Technique (SMOTE), Support Vector Machine SMOTE (SVMSMOTE) and SMOTE with Edited Nearest Neighbors (SMOTEEN). The classifiers were logistic regression (LR), multilayer perceptron (MLP), decision tree (DT) and random forest (RF). We evaluated them with various metrics and compared models with the kappa score. A complete case analysis fitted the RF (0.78) better than other models, for which SI performed best. The DT, RF, and MLP performed better with SVMSMOTE. The RF, DT and MLP had the overall best performance, contributed by imputation or resampling (SMOTE and SVMSMOTE). We recommend carefully selecting resampling and imputation techniques and comparing them with complete cases before deciding on the preprocessing approach used to test AMS data with ML models.
Growth Performance of Sabia Grass Irrigated by Drippers Installed in Subsurface
Authors: Rocha Mayara Oliveira , de Miranda Amilton Gabriel Siqueira , da Silva Policarpo Aguiar , de Oliveira Job Teixeira , da Cunha Fernando França
Published: September 2024

Studies to improve the use of subsurface drippers in pasture formation are needed. Therefore, the objective of this study was to evaluate the germination and emergence of Sabia grass as a function of drippers installed at different depths. The study was conducted in pots in Viçosa, Minas Gerais State, Brazil. The experiment was conducted using a completely randomized design with four replicates. The experimental layout featured split plots over time, where the main plots consisted of three cultivation cycles and the subplots represented various dripper installation depths. The three sowing dates were 26 March, 12 April, and 29 April 2022. Drip tapes were installed at seven different depths: 0 (superficial), 5, 10, 15, 20, 25, and 30 cm. The results showed that the reduction in water potential, associated with increased temperature, resulted in lower performance of Sabia grass seeds. Seed germination and parameters related to germination speed were negatively impacted by the increase in dripper installation depth, with a 30–40% reduction in germination speed observed at depths greater than 15 cm. Drippers installed at 15–20 cm depth in clayey soil were ideal, providing a balance between reducing soil water evaporation and maintaining seedling emergence rates. Compared to surface installation, this depth improved seed performance by up to 25%, while enhancing operability and minimizing water loss. It is recommended to install drippers at a depth of 15–20 cm in subsurface drip irrigation systems in clayey soil areas to achieve benefits such as decreased soil water evaporation and improved operability compared to surface systems.
Effects of Interactions between Feeding Patterns and the Gut Microbiota on Pig Reproductive Performance
Authors: Wang Mingyu , Yue Jiaqi , Lv Guangquan , Wang Yaxin , Guo Ao , Liu Zhe , Yu Taiyong , Yang Gongshe
Published: September 2024

The feeding mode is an important factor affecting the reproductive performance of pigs. The composition and expression of the intestinal microbiota are closely related to the physiological and biochemical indicators of animals. Therefore, to explore the impact of different feeding patterns on the reproductive performance of pigs, this study collected reproductive performance data from 1607 Yorkshire pigs raised under different feeding patterns and conducted a fixed-effect variance analysis. Among them, 731 were in the artificial feeding (AM) group and 876 were in the feeding station feeding (SM) group. Additionally, 40 Yorkshire sows in the late gestation period were randomly selected from each feeding mode for intestinal microbiota analysis. The results of the analysis showed that, in the AM group, both the number of birth deformities (NBD) and the number of stillbirths (NSB) were significantly greater than they were in the SM group (p < 0.05). Additionally, the total number born (TNB) in the AM group was significantly lower than that in the SM group (p < 0.05). The results of the intestinal microbiota analysis revealed that at the phylum level, there were significant differences in nine bacterial taxa between the AM and SM groups (p < 0.05). At the genus level, the abundance of a variety of beneficial bacteria related to reproductive performance in the SM group was significantly greater than that in the AM group. Finally, fecal metabolomic analysis revealed that the contents of butyric acid, isovaleric acid, valeric acid, and isobutyric acid, which are associated with reproductive performance, in the feces of sows in the SM group were significantly higher than those in the AM group (p < 0.05). These results indicate that different feeding methods can affect the gut microbiota composition of Yorkshire pigs and further influence the reproductive performance of pigs through the gut microbiota–metabolic product pathway. The results of this study provide valuable insights for further exploring the relationships between feeding modes, intestinal microbial composition, and host phenotypes.
Carbapenem-Resistant Enterobacterales in the Western Balkans: Addressing Gaps in European AMR Surveillance Map
Authors: Brkic Snezana , Cirkovic Ivana
Published: September 2024

In the context of global efforts to combat antimicrobial resistance (AMR), the importance of comprehensive AMR data is more crucial than ever. AMR surveillance networks, such as the European Antimicrobial Resistance Surveillance Network (EARS-Net) and the Central Asian and European Surveillance of Antimicrobial Resistance (CAESAR), support member states in obtaining high-quality AMR data. Nevertheless, data gaps persist in some countries, including those in the Western Balkans (WBs), a region with high AMR rates. This review analyzed existing research on carbapenem-resistant Enterobacterales (CRE) to better understand the AMR landscape in the WB countries. The most prevalent CRE was Klebsiella pneumoniae, followed by Escherichia coli, Enterobacter cloacae, and Proteus mirabilis, with sporadic cases of Morganella morganii, Providencia spp., Klebsiella oxytoca, and Citrobacter sedlakii. Carbapenemase production was identified as the most common mechanism of carbapenem resistance, but other resistance mechanisms were not investigated. An increasing trend in carbapenem resistance has been observed over the last decade, alongside a shift in carbapenemase epidemiology from the NDM type in 2013–2014 to the OXA-48 type in recent years. Few studies have applied whole-genome sequencing for CRE analysis, which has demonstrated the spread of resistance determinants across different niches and over time, emphasizing the importance of molecular-based research. The overall low number of studies in the WB countries can be attributed to limited resources, highlighting the need for enhanced support in education, training, technology, and equipment to improve data collection and evaluation.
Polyphenolic Screening and the Antioxidant Activity of Grape Pomace Extracts of Romanian White and Red Grape Varieties
Authors: Radulescu Cristiana , Olteanu Radu Lucian , Buruleanu Claudia Lavinia , (Tudorache) Mihaela Nechifor , Dulama Ioana Daniela , Stirbescu Raluca Maria , Bucurica Ioan Alin , Stanescu Sorina Geanina , Banica Andreea Laura
Published: September 2024

Due to its valuable organic compounds, grape pomace represents a valuable resource in the creation of value-added food products. In this study, we investigated grape pomace hydroalcoholic extracts obtained by ultrasonication from two white and two red Romanian grape varieties. The phytochemical parameters, i.e., polyphenolics, flavonoids, anthocyanins, condensed tannins content, and antioxidant activity, were determined by UV-Vis spectrometry. The statistical analysis revealed that Tămâioasă Românească and Negru de Drăgășani, respectively, and Fetească Albă and Fetească Neagră are similar to each other. Significant differences among the pomaces obtained from different grape varieties were noticed in terms of their phenolic contents. The red varieties (Fetească Neagră and Negru de Drăgășani) were richest in terms of total phenolics and total anthocyanins, respectively. The antioxidant activity of extracts obtained from grape pomace showed that Negru de Drăgășani had the higher value due to its high amounts of polyphenols, followed by Fetească Neagră, Fetească Albă, and Tămâioasă Românească. Higher levels of bioactive polyphenolic substances, i.e., catechin, myricetin, resveratrol, and vanillic acid, were found in the pomace of Negru de Drăgășani extracts using high-performance liquid chromatography. These results emphasize the potential of the Negru de Drăgășani variety to be further exploited for nutritional and functional applications.
Thermal Behavior and Infrared Absorbance Bands of Citric Acid
Authors: Tsioptsias Costas , Panagiotou Afroditi , Mitlianga Paraskevi
Published: September 2024

Citric acid is widely used in the Food and Pharmaceutical Industry. Various issues regarding its thermal behavior and infrared spectrum require clarification. Here, we studied citric acid monohydrate (raw, heated, freeze-dried and recrystallized from D2O) via Differential Scanning Calorimetry, Thermogravimetric Analysis, Infrared Spectroscopy, and antioxidant capacity assay. Also, we used ab initio Density Functional Theory calculations for further supporting the interpretations of the experimental results. Citric acid monohydrate exhibits desolvation inability and upon heating does not dehydrate but esterifies. Nor by freeze drying can it be dehydrated. The heated sample is not anhydrous, it exhibits melting inability, and any fluidization occurs simultaneously with decomposition. In other words, the interpretations regarding the two endothermic peaks in the DSC curve of citric acid that have been attributed to water evaporation and melting are not correct. The increase in the molecular weight due to esterification is most likely responsible for the increased antioxidant/chelation capacity of the heated sample. We concluded that what we call citric acid monohydrate and anhydrous do not exist in a pure form (in the solid state) and actually are mixtures of different compositions of citric acid, water and a citric acid oligomer that is produced through esterification. The esterification reaction seems to be able to proceed easily under mild heating or even at room temperature. The presence of the ester oligomer and water affect the infrared spectrum of citric acid monohydrate and anhydrous and is responsible for the existence of multiple peaks in the C=O stretching region, which partially overlaps with the water H-O-H bending vibration. The insights presented in this work could be useful for optimizing the design, performance and quality of food and drug products in which citric acid is used.
Diversity of Host Species and Optimized Cultivation Practices for Enhanced Bioactive Compound Production in Cordyceps militaris
Authors: Trung Nguyen Quang , Quyen Phan Duong Thuc , Ngoc Nguyen Thi Thanh , Minh Truong Ngoc
Published: September 2024

Cordyceps militaris, recognized for its diverse and potent medicinal properties, plays a critical role in herbal medicine. This study investigates the genus Cordyceps, particularly focusing on C. militaris, a species widely utilized in East Asian traditional medicine for its therapeutic properties. C. militaris is rich in bioactive compounds, including cordycepin, adenosine, polysaccharides, ergosterol, and mannitol, which contribute to its broad physiological activities. The research aims to explore the diversity of host species in the cultivation of C. militaris and assess their impact on the biological activity and chemical composition of the fungus. The study highlights the variability in the efficacy of bioactive compounds due to different cultivation conditions and host species, emphasizing the need for standardized cultivation practices. Advances in genetic engineering and fermentation technology have significantly enhanced the production of these metabolites, supporting the sustainable scale-up of C. militaris cultivation. Future research should continue to explore the molecular mechanisms of its bioactive compounds, identify new clinical applications, and improve production efficiency and environmental sustainability. This comprehensive review provides insights for researchers, healthcare professionals, and cultivators on optimizing C. militaris for medicinal and commercial applications.
Log-Based Fault Localization with Unsupervised Log Segmentation
Authors: Dobrowolski Wojciech , Iwach-Kowalski Kamil , Nikodem Maciej , Unold Olgierd
Published: September 2024

Localizing faults in a software is a tedious process. The manual approach is becoming impractical because of the large size and complexity of contemporary computer systems as well as their logs, which are often the primary source of information about the fault. Log-based Fault Localization (LBFL) is a popular method applied for this purpose. However, in real-world scenarios, this method is vulnerable to a large number of previously unseen log lines. In this paper, we propose a novel method that can guide programmers to the location of a fault by creating a hierarchy of log lines with the highest rank, selected by the traditional LBFL method. We use the intuition that the symptoms of faults are in the context of normal behavior, whereas suspicious log lines grouped together are from new or additional functionalities turned on during faulty execution. To obtain this context, we used unsupervised log sequence segmentation, which has been previously used to segment log sequences into meaningful segments. Experiments on real-life examples show that our method reduces the effort to find the most crucial logs by up to 64% compared with the traditional timestamp approach. We demonstrate that context is highly useful in advancing fault localization, showing the possibility of further speeding up the process.
Combined ResNet Attention Multi-Head Net (CRAMNet): A Novel Approach to Fault Diagnosis of Rolling Bearings Using Acoustic Radiation Signals and Advanced Deep Learning Techniques
Authors: Xu Xiaozheng , Li Ying , Ding Xuebao
Published: September 2024

The fault diagnosis of rolling bearing acoustic radiation signals holds significant importance in industrial equipment maintenance. It effectively prevents equipment failures and downtime, ensuring the smooth operation of the production process. Compared with traditional vibration signals, acoustic radiation signals have the advantage of non-contact measurement. They can diagnose faults in special conditions where sensors cannot be installed and provide more comprehensive equipment status information. Therefore, to extract the fault characteristic information of rolling bearings from complex acoustic signals, this paper proposes an advanced deep learning model combining Gramian Angular Field (GAF), ResNet1D, ResNet2D, and multi-head attention mechanism, named CRAMNet (Combined ResNet Attention Multi-Head Net), to diagnose the faults of rolling bearing acoustic radiation signals. Firstly, this method includes converting one-dimensional signals into GAF images and performing data standardization and segmentation. Then, the method utilizes ResNet1D to extract features from one-dimensional signals and ResNet2D to extract features from GAF images. Further, it combines the multi-head attention mechanism to enhance feature representation and capture dependencies between different channels. Finally, this paper compares the proposed method with several traditional models (including CNN, LSTM, DenseNet, and CNN-Transformers). Experimental results show that the proposed method performs outstandingly in terms of accuracy and robustness. The combination of residual networks and multi-head attention mechanism in the model significantly enhances its ability to accurately diagnose rolling bearing faults, proving the superiority of the algorithm.
Development and Validation of a Tool for VBOI (Virtual Body Ownership Illusion) Level Assessment
Authors: Yoo Gayoung , Kim Kyungdoh
Published: September 2024

Virtual Body Ownership Illusion (Virtual BOI) refers to the perceptual, cognitive, and behavioral changes that occur due to the illusion that a virtual body is one’s own actual body. Recent research has focused on inducing Virtual Body Ownership Illusion (Virtual BOI) using various physical conditions of VR environments such as haptic feedback and 360-degree immersion, among others. The level of Virtual BOI has been recognized as an important factor in VR-based clinical therapy programs where patient immersion is crucial. However, a common issue is the lack of standardized evaluation tools for Virtual BOI, with most experiments relying on ad hoc tools based on experimental conditions or lacking consideration for the physical design elements of VR. This measurement tool was designed to consider the characteristics of recent VR devices, such as haptics and hand tracking, in the design of experiments and questionnaires. The tool is composed of sub-attributes related to VR technology, including Embodiment, Presence, Visuo-tactile, Visuo-proprioceptive, and Visuo-Motor. Based on a review of the existing literature, we hypothesized that the Virtual BOI scores would vary depending on manipulation methods, viewpoints, and haptic conditions. An experiment was conducted with 39 participants, who performed the same task under four different conditions using a virtual hand. Virtual BOI scores were assessed using the evaluation tool developed for this study. The questionnaire underwent CFA, and three items with factor loadings below 0.5 were removed, resulting in a total of 14 items. Each subscale demonstrated high reliability, with Cronbach’s alpha values greater than 0.60. When developing experiments, clinical programs, or VR content related to Virtual BOI, the evaluation tool presented in this study can be used to assess the level of Virtual BOI. Additionally, by considering technological elements such as haptics and hand tracking, VR environments can be designed to enhance the level of Virtual BOI.
Recent Advances in Solar Thermal Selective Coatings for Solar Power Applications: Technology Categorization, Preparation Methods, and Induced Aging Mechanisms
Authors: Zayed Mohamed E.
Published: September 2024

Solar thermal selective coatings (STSCs) are crucial for enhancing the thermal efficiency of receivers in solar power applications. Enhancing the photothermal conversion performance of STSCs is crucial for improving the thermo-economic efficiency of these sustainable high-temperature applications. Wherefore, in this study, we comprehensively review the ongoing technologies and enhanced strategies of solar thermal selective coatings, highlighting their advantages, drawbacks, technological advancements, and mechanisms. This review comprehensively examines the latest advancements in material synthesis, coating structure designs, and induced aging mechanisms of STSCs. It critically discusses the various types of STSCs, and the research techniques employed to assess photothermal performance and enhance thermal stability. Lastly, the limitations and future expectations of STSCs are also highlighted. This paper serves as a detailed guide for planning and implementing various types of STSCs in diverse solar power applications.
Fundus-DANet: Dilated Convolution and Fusion Attention Mechanism for Multilabel Retinal Fundus Image Classification
Authors: Yan Yang , Yang Liu , Huang Wenbo
Published: September 2024

The difficulty of classifying retinal fundus images with one or more illnesses present or missing is known as fundus multi-lesion classification. The challenges faced by current approaches include the inability to extract comparable morphological features from images of different lesions and the inability to resolve the issue of the same lesion, which presents significant feature variances due to grading disparities. This paper proposes a multi-disease recognition network model, Fundus-DANet, based on the dilated convolution. It has two sub-modules to address the aforementioned issues: the interclass learning module (ILM) and the dilated-convolution convolutional block attention module (DA-CBAM). The DA-CBAM uses a convolutional block attention module (CBAM) and dilated convolution to extract and merge multiscale information from images. The ILM uses the channel attention mechanism to map the features to lower dimensions, facilitating exploring latent relationships between various categories. The results demonstrate that this model outperforms previous models in classifying fundus multilocular lesions in the OIA-ODIR dataset with 93% accuracy.
Robotic Manipulation of Cumulus–Oocyte Complexes for Cumulus Cell Removal
Authors: Zhai Rongan , Hao Miao , Wang Yong , Ru Changhai , Zhu Junhui
Published: September 2024

The removal of cumulus cells from cumulus–oocyte complexes is a critical step in clinical in vitro fertilization. Since the oocyte is partially occluded by the surrounding cumulus cells and individual cumulus cells are small in size, it is difficult for embryologists to assess the oocyte's maturity before cumulus cell removal and to completely remove all the cumulus cells manually . Furthermore, it is easy for the oocyte to become lost inside the micropipette during aspiration due to the inaccuracy of manual control. To deal with these difficulties, a robotic system was developed to completely remove cumulus cells from mature oocytes. In this study, an EPSANet50 network was developed to accurately assess the maturity of oocytes, avoiding the removal of cumulus cells around the immature oocyte. An adaptive controller was designed to accurately position oocytes at the target position, reducing the loss of oocytes inside the micropipette. An improved Yolov5s network was proposed to quantify the number and size of cumulus cells and assess the completeness of cumulus cell removal. The experimental results on mouse cumulus–oocyte complexes showed that the robotic system had a higher success rate (98.0 ± 1.8% vs. 85.3 ± 2.4%) and lower discard rate (4.1 ± 2.7% vs. 19.6 ± 3.5%) than the manual operation. Moreover, a higher amplification rate and lower non-specific rate were also achieved by the robotic system in the subsequent genetic testing procedure, indicating reduced genetic contamination from the cumulus cells.
Multi-Body Model of Agricultural Tractor for Vibration Transmission Investigation
Authors: Rekem Jakub , Janečková Radka , Otipka Václav , Prokop Aleš , Řehák Kamil , Žlábek Pavel
Published: September 2024

This article analyses vibration transmission on agricultural tractors with the excitation from the road to the driver’s seat. A multi-body model of agricultural tractors created in Adams is presented. The main parts for the investigation of vibration transmission are the tractor body, where the only suspension elements are tyres, the tractor cabin, spring-dampers suspended at the rear and bushings at the front, and the driver seat with its pneumatic spring. A series of measurements were performed, and the model was validated using vertical acceleration values on the tractor body at four different locations. The FTire model (physical FEM-based model) was chosen to describe the behaviour of tyres. The model was created using measured tyre characteristics. Measured characteristics of spring-dampers and front cabin bushings were also implemented. For comfort investigation, ride simulations on ISO 5008 rough roads were performed. The transmission of vibrations in ride simulations was examined. A modal analysis of the linearised model was performed to confirm assumptions of the contribution of suspension elements to overall vibration levels. Finally, three case studies were conducted to better understand the model’s vibration transmission properties.
Prediction and Control of Broadband Noise Associated with Advanced Air Mobility—A Review
Authors: Hua Jie , Mankbadi Reda R.
Published: September 2024

This review presents an overview of advanced air mobility broadband noise (BBN) prediction and control techniques, highlighting significant advancements in various prediction models. Methods such as the semi-empirical Brooks–Pope–Marcolini (BPM) model, analytical Amiet model, and time-domain models based on the FW-H equation have been extensively studied. Machine learning (ML) shows promise in BBN prediction but requires extensive data training and application to noise source mechanisms. Passive control methods, such as leading and trailing edge serrations and blade tip designs, have been partially successful but often compromise the aerodynamic performance. Active control methods, like suction and blowing control, trim adjustments, and dielectric barrier discharge (DBD) plasma actuators, show great potential, with the latter two being particularly effective for reducing BBN in thin propeller structures. Overall, while progress has been made in understanding and predicting BBN, further research is needed to refine these methods and develop comprehensive noise control strategies. These advancements hold significant promise for effective and efficient noise mitigation in future AAM vehicles.
Microzonation Approach for Analyzing Regional Seismic Response: A Case Study of the Dune Deposit in Concón, Chile
Authors: Diaz-Segura Edgar Giovanny , Vielma Juan Carlos , Oviedo-Veas Jorge Eduardo
Published: September 2024

Urban areas located on complex geological formations, such as dune deposits, require detailed seismic risk assessments that extend beyond standard seismic codes. This study focuses on the city of Concón, Chile, where a significant portion of the urban area is situated on a coastal dune deposit. The research integrates seismic microzonation with a three-dimensional finite element model (3D FEM) to comprehensively evaluate the regional seismic response. Field data from 208 strategically distributed points were collected and combined with geotechnical and geomorphological information to construct a detailed 3D model of the region. This model allowed for the simulation of seismic behavior under various conditions, highlighting the limitations of general seismic codes in capturing local variations in seismic response. The results underscore the importance of considering local geological conditions in structural design, particularly in areas with irregular topography and complex subsurface conditions. This study concludes that incorporating microzonation into urban planning and seismic analysis can significantly enhance infrastructure resilience and disaster preparedness, providing a replicable approach for other cities facing similar geological challenges.
Bias and Linking Error in Fixed Item Parameter Calibration
Authors: Robitzsch Alexander
Published: September 2024

The two-parameter logistic (2PL) item response theory (IRT) model is frequently applied to analyze group differences for multivariate binary random variables. The item parameters in the 2PL model are frequently fixed when estimating the mean and the standard deviation for a group of interest. This method is also called fixed item parameter calibration (FIPC). In this article, the bias and the linking error of the FIPC approach are analytically derived in the presence of random uniform differential item functioning (DIF). The adequacy of the analytical findings was validated in a simulation study. It turned out that the extent of the bias and the variance in distribution parameters increases with increasing variance of random DIF effects.
Comparative Analysis of Ligninolytic Potential among Pleurotus ostreatus and Fusarium sp. with a Special Focus on Versatile Peroxidase
Authors: Parmar Manisha , Patel Sayeed A. H. , Phutela Urmila Gupta , Dhawan Manish
Published: September 2024

Lignocellulosic biomass is contemplated to be an inexpensive and copious feedstock that can be used for numerous industrial applications. However, lignin forms the lignin sheath and provides a physical barrier to enzymatic hydrolysis. In addition, lignin physically blocks cellulase, preventing it from being combined with the substrate in a process known as non-productive binding. Therefore, the depletion of lignin is a crucial method for obtaining fermentable sugars from the lignocellulosic biomass. Different white-rot fungi secrete different sets of lignin-mineralizing enzymes and each fungus secretes one or more of the three enzymes essential for lignin degradation. Among efficient redox enzymes, versatile peroxidase is extensively studied for its ability to degrade aromatics without the need for a mediator or polyvalent catalytic site. However, the presence of versatile peroxidase in F. spp. has not been studied. This study was planned with the objective of screening and comparing the production of versatile peroxidase enzymes from F. spp. and a standard culture of Pleurotus ostreatus MTCC-142. These fungal strains were first screened on solid media containing tannic acid, malachite green, or bromocresol green. The potency index for the tannic acid, malachite green, and bromocresol green on the 16th day of incubation was reported to be 1.28, 1.07, 1.09, and 1.10, respectively. Versatile peroxidase production patterns were investigated under solid state fermentation conditions for a period of 25 days at different temperatures ranging from 10 to 35 °C. The highest versatile peroxidase activity (592 UL−1) in F. sp. was observed at 30 °C after the 7th day of incubation. The molecular confirmation showed the presence of the vp gene in F. sp. along with Pleurotus ostreatus MTCC-142. The results determined that F. sp. possesses a versatile peroxidase enzyme and is able to degrade lignin efficiently, and thus it could be utilized as an alternative to other ligninolytic enzyme-producing fungi.