bluuebunny/crossref_metadata_2025 huggingface dataset:
ESE-YOLOv8: A Novel Object Detection Algorithm for Safety Belt Detection during Working at Heights
Authors: Zhou Qirui , Liu Dandan , An Kang
Published: July 2024

To address the challenges associated with supervising workers who wear safety belts while working at heights, this study proposes a solution involving the utilization of an object detection model to replace manual supervision. A novel object detection model, named ESE-YOLOv8, is introduced. The integration of the Efficient Multi-Scale Attention (EMA) mechanism within this model enhances information entropy through cross-channel interaction and encodes spatial information into the channels, thereby enabling the model to obtain rich and significant information during feature extraction. By employing GSConv to reconstruct the neck into a slim-neck configuration, the computational load of the neck is reduced without the loss of information entropy, allowing the attention mechanism to function more effectively, thereby improving accuracy. During the model training phase, a regression loss function named the Efficient Intersection over Union (EIoU) is employed to further refine the model’s object localization capabilities. Experimental results demonstrate that the ESE-YOLOv8 model achieves an average precision of 92.7% at an IoU threshold of 50% and an average precision of 75.7% within the IoU threshold range of 50% to 95%. These results surpass the performance of the baseline model, the widely utilized YOLOv5 and demonstrate competitiveness among state-of-the-art models. Ablation experiments further confirm the effectiveness of the model’s enhancements.
Superconducting Quantum Simulation for Many-Body Physics beyond Equilibrium
Authors: Yao Yunyan , Xiang Liang
Published: July 2024

Quantum computing is an exciting field that uses quantum principles, such as quantum superposition and entanglement, to tackle complex computational problems. Superconducting quantum circuits, based on Josephson junctions, is one of the most promising physical realizations to achieve the long-term goal of building fault-tolerant quantum computers. The past decade has witnessed the rapid development of this field, where many intermediate-scale multi-qubit experiments emerged to simulate nonequilibrium quantum many-body dynamics that are challenging for classical computers. Here, we review the basic concepts of superconducting quantum simulation and their recent experimental progress in exploring exotic nonequilibrium quantum phenomena emerging in strongly interacting many-body systems, e.g., many-body localization, quantum many-body scars, and discrete time crystals. We further discuss the prospects of quantum simulation experiments to truly solve open problems in nonequilibrium many-body systems.
Characteristic Extraction and Assessment Methods for Transformers DC Bias Caused by Metro Stray Currents
Authors: Wang Aimin , Lin Sheng , Wu Guoxing , Li Xiaopeng , Wang Tao
Published: July 2024

Metro stray currents flowing into transformer-neutral points cause the high neutral DC and a transformer to operate in the DC bias state.Because neutral DC caused by stray current varies with time, the neutral DC value cannot be used as the only characteristic indicator to evaluate the DC bias risk level. Thus, unified characteristic extraction and assessment methods are proposed to evaluate the DC bias risk of a transformer caused by stray current, considering the signals of transformer-neutral DC and vibration. In the characteristic extraction method, the primary characteristics are obtained by comparing the magnitude and frequency distributions of transformer-neutral DC and vibration with and without metro stray current invasion. By analyzing the correlation coefficients, the final characteristics are obtained by clustering the primary characteristics with high correlation. Then, the magnitude and frequency characteristics are extracted and used as indicators to evaluate the DC bias risk. Moreover, to avoid the influence of manual experience on indicator weights, the entropy weight method (EWM) is used to establish the assessment model. Finally, the proposed methods are applied based on the neutral DC and vibration test data of a certain transformer. The results show that the characteristic indicators can be extracted, and the transformer DC bias risk can be evaluated by using the proposed methods.
Survival Analysis of Small Business during COVID-19 Pandemic, a Brazilian Case Study
Authors: Tonetto Jorge Luis , Pique Josep Miquel , Fochezatto Adelar , Rapetti Carina
Published: July 2024

The impact of COVID-19 on the economy was devastating. Small businesses typically have few resources to fight against such adversity. Many businesses remained closed for some time during the pandemic period, resulting in significant consequences for people in terms of jobs, income and life. The objective of this research is to identify the factors that contributed to increasing company failures during the pandemic. Furthermore, this study aims to verify whether the size of the companies, the sectors of economic activity in which they operate and their geographic location influence enterprise failure. This article analyzes the survival of 8931 small businesses from 2017 to 2023, in Rio Grande do Sul, Brazil. The study applied a survival analysis using the Kaplan–Meier procedure, complemented with the Cox procedure, to determine the effects of the size of companies, sector activity and location on the survival time. The results indicate that survival is much higher in small companies with large revenues that are located in the Campaign and West Frontier regions, as well as in the Northeast, North, Production, South, Taquari, and Rio Pardo Valleys regions, whereas the survival rates were extremely lower in the commercial sector and in financial intermediation activities. In the second analysis restricted to the commerce sector, the data highlighted the retail activities, accommodation and food activities sectors as the most affected in terms of overall survival. The results indicated that the survival of small business remained relatively strong during the COVID-19 pandemic, signaling the pertinent support from the government. The smallest business with revenues under USD 15,576 (BRL 81,000) per year were the most affected, with only 39% survival after 7 years. Some activities and some regions suffered more than others, emphasizing the need for special attention from authorities in future catastrophes.
An Effective Mechanism for FOG Computing Assisted Function Based on Trustworthy Forwarding Scheme (IOT)
Authors: Hameed Fatimah Mohammed Hameed , Kurnaz Sefer
Published: July 2024

As the Internet of Things (IoT) continues to proliferate, the demand for efficient and secure data processing at the network edge has grown exponentially. Fog computing, a paradigm that extends cloud capabilities to the edge of the network, plays a pivotal role in meeting these requirements. In this context, the reliable and trustworthy forwarding of data is of paramount importance. This paper presents an innovative mechanism designed to ensure the trustworthiness of data forwarding in the context of MQTT (Message Queuing Telemetry Transport), a widely adopted IoT communication protocol. Our proposed mechanism leverages the inherent advantages of MQTT to establish a robust and secure data-forwarding scheme. It integrates fog computing resources seamlessly into the MQTT ecosystem, enhancing data reliability and security. The mechanism employs trust models to evaluate the credibility of IoT devices and fog nodes involved in data forwarding, enabling informed decisions at each stage of the transmission process. Key components of the mechanism include secure communication protocols, authentication mechanisms, and data integrity verification. The proposed secure communication protocols (TLS/SSL, MQTTS, and PKI) and data integrity verification methods (MAC, digital signatures, checksums, and CRC) provide a robust framework for ensuring secure and trustworthy data transmission in IoT systems. These elements collectively contribute to the establishment of a reliable data forwarding pipeline within MQTT. Additionally, the mechanism prioritizes low-latency communication and efficient resource utilization, aligning with the real-time requirements of IoT applications. Through empirical evaluations and simulations, the research demonstrates the effectiveness of our proposed mechanism in improving the trustworthiness of data forwarding, while minimizing overhead, as the experiment was conducted with 15 fog nodes, and the maximum Level of Trust (LoT) score was 0.968, which is very high, with an estimated accuracy of 97.63%. The results indicate that our approach significantly enhances data security and reliability in MQTT-based IoT environments, thereby facilitating the seamless integration of fog computing resources for edge processing.
A Hybrid Stacking Model for Enhanced Short-Term Load Forecasting
Authors: Guo Fusen , Mo Huadong , Wu Jianzhang , Pan Lei , Zhou Hailing , Zhang Zhibo , Li Lin , Huang Fengling
Published: July 2024

The high penetration of distributed energy resources poses significant challenges to the dispatch and operation of power systems. Improving the accuracy of short-term load forecasting (STLF) can optimize grid management, thus leading to increased economic and social benefits. Currently, some simple AI and hybrid models have issues to deal with and struggle with multivariate dependencies, long-term dependencies, and nonlinear relationships. This paper proposes a novel hybrid model for short-term load forecasting (STLF) that integrates multiple AI models with Lasso regression using the stacking technique. The base learners include ANN, XgBoost, LSTM, Stacked LSTM, and Bi-LSTM, while lasso regression serves as the metalearner. By considering factors such as temperature, rainfall, and daily electricity prices, the model aims to more accurately reflect real-world conditions and enhance predictive accuracy. Empirical analyses on real-world datasets from Australia and Spain show significant improvements in the forecasting accuracy, with a substantial reduction in the mean absolute percentage error (MAPE) compared to existing hybrid models and individual AI models. This research highlights the efficiency of the stacking technique in improving STLF accuracy, thus suggesting potential operational efficiency benefits for the power industry.
A Secure GNN Training Framework for Partially Observable Graph
Authors: An Dongdong , Yang Yi , Liu Wenyan , Zhao Qin , Liu Jing , Qi Hongda , Lian Jie
Published: July 2024

Graph Neural Networks (GNNs) are susceptible to adversarial injection attacks, potentially compromising the model integrity, reducing accuracy, and posing security risks. However, most of the current countermeasures focus on enhancing the robustness of GNNs rather than directly addressing these specific attacks. The challenge stems from the difficulty of protecting all nodes in the entire graph and the agnostic of the attackers. Therefore, we propose a secure training strategy for GNNs that counters the vulnerability to adversarial injection attacks and overcomes the obstacle of partial observability in existing defense mechanisms—where defenders are only aware of the graph’s post-attack structure and node attributes, without the identification of compromised nodes. Our strategy not only protects specific nodes but also extends security to all nodes in the graph. We model the graph security issues as a Partially Observable Markov Decision Process (POMDP) and use Graph Convolutional Memory (GCM) to transform the observations of a POMDP into states with temporal memory proceeding to use reinforcement learning to solve for the optimal defensive strategy. Finally, we prevent learning from malicious nodes by limiting the convolutional scope, thus defending against adversarial injection attacks. Our defense method is evaluated on five datasets, achieving an accuracy range of 74% to 86.7%, which represents an enhancement of approximately 5.09% to 100.26% over post-attack accuracies. Compared with various traditional experimental models, our method shows an accuracy improvement ranging from 0.82% to 100.26%.
Effects of Fractional Time Delay as a Low-Power True Time Delay Digital Beamforming Architecture
Authors: Liebold Zachary , Broughton Bob , Shemelya Corey
Published: July 2024

True time delay digital beamforming enables large squint-free bandwidths and high beamcounts, ideal for Low Earth Orbit (LEO) satellite communication links. This work proposes a true time delay architecture using Variable Fractional Delay (VFD). True time delay eliminates many analog beamforming performance constraints including inaccurate beam steering and limited beamcounts, while managing system quantization error. This article presents a method of implementing true time delay using a VFD digital filter with sufficient time resolution to minimize quantization error and enable both gigahertz bandwidths and sampling frequencies. Simulations of antenna patterns utilizing the proposed VFD digital filters demonstrate satisfactory LEO beamforming performance with only a 29-tap filter. The VFD filter was implemented using a Xilinx Virtex Ultrascale FPGA and demonstrated a 1077% reduction in dynamic power and a minimum 498% reduction in logic resources, with only a modest increase in multipliers required when compared to Farrow-based architectures previously proposed in the literature.
Augmented Millimeter Wave Radar and Vision Fusion Simulator for Roadside Perception
Authors: Liu Haodong , Wan Jian , Zhou Peng , Ding Shanshan , Huang Wei
Published: July 2024

Millimeter-wave radar has the advantages of strong penetration, high-precision speed detection and low power consumption. It can be used to conduct robust object detection in abnormal lighting and severe weather conditions. The emerging 4D millimeter-wave radar has improved the quality and quantity of generated point clouds. Adding radar–camera fusion enhances the tracking reliability of transportation system operation. However, it is challenging due to the absence of standardized testing methods. Hence, this paper proposes a radar–camera fusion algorithm testing framework in a highway roadside scenario using SUMO and CARLA simulators. First, we propose a 4D millimeter-wave radar simulation method. A roadside multi-sensor perception dataset is generated in a 3D environment through co-simulation. Then, deep-learning object detection models are trained under different weather and lighting conditions. Finally, we propose a baseline fusion method for the algorithm testing framework. This framework provides a realistic virtual environment for device selection, algorithm testing and parameter tuning for millimeter-wave radar–camera fusion algorithms. Solutions show that the method proposed in this paper can provide a realistic virtual environment for radar–camera fusion algorithm testing for roadside traffic perception. Compared to the camera-only tracking method, the radar–vision fusion method proposed significantly improves tracking performance in rainy night scenarios. The trajectory RMSE is improved by 68.61% in expressway scenarios and 67.45% in urban scenarios. This method can also be applied to improve the detection of stop-and-go waves on congested expressways.
Comprehensive Chassis Control Strategy Based on Coordination of Traction/Braking Distribution and Active Roll Control
Authors: Feng Jianbo , Gao Zepeng , Guo Bingying , Du Cong
Published: July 2024

A coordinated control of front/rear traction, four-wheel independent braking, and an active roll control system is proposed in this paper to improve overall vehicle cornering performance. The control algorithm is structured in a hierarchical form: the supervisory controller is used to calculate the desired yaw rate and roll angle based on the driver input and vehicle states; the upper-level controller is utilized to decide the target longitudinal tire forces, yaw moment, and anti-roll moment based on the sliding mode control method; and the control allocator is used to optimally map the virtual control input to the control commands of specific actuators. Co-simulations of MATLAB/Simulink and CarSim were conducted to verify the performance enhancement of the proposed controller. The results suggest that the proposed controller can effectively enhance the driving performance in limit cornering while maintaining lateral stability, and it reduces tire usage, as indicated by the index of tire dissipation energy when compared to control methods such as AWD, AWD-ESC, and ICC.
Correction: Tasnim Mowri et al. Assessing the Impact of First-Life Lithium-Ion Battery Degradation on Second-Life Performance. Energies 2024, 17, 501
Authors: Tasnim Mowri Sadia , Barai Anup , Moharana Sanghamitra , Gupta Aniruddha , Marco James
Published: July 2024

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Unique Coolant Supply Passage Arrangements to Induce Large-Scale Vortex within Turbine Blade Interior Leading Edge Chambers
Authors: Cai Yang , Liu Xinzi , Sun Yu , Fan Xiaojun , Wang Jiao
Published: July 2024

Gas turbines are widely applied in many fields, and blade cooling is a key way to improve gas turbines’ power and efficiency. In order to explore a high-efficiency cooling method, a new variant configuration with unique coolant supply passage arrangements is proposed and explored in this paper. The numerical simulation method of solving the Navier–Stokes equations is used after mesh independence calculation and turbulence model validation. The results show that the variant structure has better streamlines distribution with double vortex flows in both the inner and outer chambers. Compared to the original configuration, the heat transfer intensity in the outer chamber is improved, and the globally averaged Nusselt number is 17.1% larger. The case with uniformly distributed nozzles has the best flow and heat transfer performance. As the nozzle number increases, the total pressure loss and friction coefficient decrease, but the heat transfer increases first and then decreases. The case of three nozzles has the best comprehensive cooling behavior. The aspect ratio has important influences on the double-vortex cooling configuration. Cases with small aspect ratios have higher local heat transfer intensity, but the flow loss is larger. The case with aspect ratio 4 has the best cooling performance.
Simulation Study on the Effect of Cement Shrinkage on the Stress Distribution of Large Tonnage Disc-Type Suspension Porcelain Insulators
Authors: Zhao Jianli , Chen Yixin , Dou Wenping , Cao Bin , Wang Liming , Yin Fanghui
Published: July 2024

With the development of UHV transmission technology, large-tonnage disc-type suspension porcelain insulators have been widely used. Insulators with cylindrical heads have the advantages of light weight and high strength compared with traditional insulators with conical heads. Cement is an important part of disc-type suspension porcelain insulators. The drying shrinkage of cement can lead to sliding between cement and porcelain. It can also transform the stress distribution of the porcelain, thus influencing the overall long-term mechanical performance of the insulators. In this paper, the effect of the shrinkage of cement on the stress distribution of porcelain insulators was studied by simulation. In addition, the effect of the drying shrinkage rates of cement on insulators with cylindrical and conical heads were compared. The simulation results show that cylindrical-head insulators can better resist the stress change caused by cement shrinkage than the conical-head insulators, which was beneficial to the long-term performance of the insulators. Based on the tensile stress of porcelain parts, the recommended range of the drying shrinkage rate of cement for insulators with cylindrical heads was presented. The research results are of practical value for the selection of cement.
Results of Experimental Research on Microflame Burners for Hot Water Boilers and Gas Turbines
Authors: Beloev Hristo I. , Dostiyarov Abay M. , Sarakeshova Nurbubi N. , Makzumova Ainura K. , Iliev Iliya K.
Published: July 2024

The study aims to address the need for cleaner and more efficient combustion technologies in the context of global energy demand and sustainability goals. It focuses on microflame techniques to enhance the performance of gas turbines and water heating boilers. This research investigated, for the first time, the operation of a micromodular burner for hot water boilers and a microflame burner for gas turbines, based on patented inventions. Methods for assessing efficiency included analyzing heat flows, fuel conversion rates to thermal energy, and emission analysis. Using high-precision measuring equipment, such as TESTO 350-XL, thermocouples, flow meters, and others, optimal operating modes were determined for the gas turbine combustion chamber and hot water boiler. This resulted in achieving high efficiency and reducing harmful emission levels (NOx < 15 ppm, CO < 140 ppm). Theoretical calculations were compared with experimental data, confirming the reliability of the results obtained.
Experimental Evaluation of Enhanced Oil Recovery in Shale Reservoirs Using Different Media
Authors: Tao Jiaping , Meng Siwei , Li Dongxu , Liang Lihao , Liu He
Published: July 2024

The presence of highly developed micro-nano pores and poor pore connectivity constrains the development of shale oil. Given the rapid decline in oil production , enhanced oil recovery (EOR) technologies are necessary for shale oil development. The shale oil reservoirs in China are mainly continental and characterized by high heterogeneity, low overall maturity, and inferior crude oil quality. Therefore, it is more challenging to achieve a desirably high recovery factor. The Qingshankou Formation is a typical continental shale oil reservoir, with high clay content and well-developed bedding. This paper introduced high-precision non-destructive nuclear magnetic resonance technology to carry out a systematic and targeted study. The EOR performances and oil recovery factors related to different pore sizes were quantified to identify the most suitable method. The results show that surfactant, CH4, and CO2 can recover oil effectively in the first cycle. As the huff-and-puff process continues, the oil saturated in the shale gradually decreases, and the EOR performance of the surfactant and CH4 is considerably degraded. Meanwhile, CO2 can efficiently recover oil in small pores (<50 nm) and maintain good EOR performance in the second and third cycles. After four huff-and-puff cycles, the average oil recovery of CO2 is 38.22%, which is much higher than that of surfactant (29.82%) and CH4 (19.36%). CO2 is the most applicable medium of the three to enhance shale oil recovery in the Qingshankou Formation. Additionally, the injection pressure of surfactant increased the fastest in the injection process, showing a low flowability in nano-pores. Thus, in the actual shale oil formations, the swept volume of surfactant will be suppressed, and the actual EOR performance of the surfactant may be limited. The findings of this paper can provide theoretical support for the efficient development of continental shale oil reservoirs.
Assessment of Electromagnetic Fields in Trolleybuses and Electric Buses: A Study of Municipal Transport Company Lublin’s Fleet
Authors: Mazurek Paweł A. , Chudy Aleksander , Hołyszko Piotr
Published: July 2024

As electromobility and especially the electrification of public transportation develops, it is necessary to safeguard human health and minimize environmental impact. Electromagnetic fields generated by the current flowing through on-board batteries, installations, converters, propulsion, air conditioning, heating, lighting, or wireless communication systems in these vehicles may pose risks to drivers and passengers. This research investigates electromagnetic fields induced by extreme low-frequency currents and permanent magnets on electric and trolleybuses implanted in Lublin, Poland. The identification of electromagnetic fields concerned an electric bus model and two trolleybus models. A comparative analysis of the results obtained with the permissible limits in the environment was carried out.
Enhancing the Properties of Nanostructure TiO2 Thin Film via Calcination Temperature for Solar Cell Application
Authors: Arifin Nurliyana Mohamad , Mhd Noor Ervina Efzan , Mohamad Fariza , Mohamad Norhidayah , Mohamed Muzni Nur Haslinda
Published: July 2024

In this study, titanium dioxide (TiO2) was deposited onto a fluorine-doped tin oxide (FTO) substrate using the sol–gel spin coating method. Through the implementation of calcination treatment on the thin film, enhancements were observed in terms of structural, optical, and morphological properties. Various calcination temperatures were explored, with TiO2 annealed at 600 °C identified as the optimal sample. Analysis of the X-ray diffraction spectroscopy (XRD) pattern revealed the prominent orientation plane of (101), indicating the presence of anatase TiO2 with a tetragonal pattern at this temperature. Despite fluctuations in the optical spectrum, the highest transmittance of 80% was observed in the visible region within the wavelength range of 400 nm. The estimated band-gap value of 3.45 eV reaffirmed the characteristic of TiO2. Surface analysis indicated the homogeneous growth of TiO2, uniformly covering the FTO substrate. Cross-sectional examination revealed a thickness of 263 nm with dense and compact nature of TiO2 thin film. No presence of defects or pores reflects a well-organized structure and high-quality formation. Significant electrical rectification properties were observed, indicating the successful formation of a p–n junction. In summary, calcination treatment was found to be crucial for enhancing the properties of the thin film, highlighting its significance in the development of solar cell applications.
Innovations in Crude-Oil Characterization: A Comprehensive Review of LF-NMR Applications
Authors: Khelil Ismail , Al-Muntaser Ameen A. , Varfolomeev Mikhail A. , Hakimi Mohammed Hail , Suwaid Muneer A. , Saeed Shadi A. , Nurgaliev Danis K. , Al-Fatesh Ahmed S. , Osman Ahmed I.
Published: July 2024

The advent of low-field nuclear magnetic resonance (LF-NMR) has revolutionized the petroleum industry by providing a swift and straightforward method for the spectroscopic characterization of crude oil. This review paper delves into the significant strides made in LF-NMR technology since its inception by Felix Bloch and Edward Purcell in 1946, particularly its application in determining the composition, viscosity, and water content of crude oil, alongside SARA (Saturates, Aromatics, Resins, and Asphaltenes) analysis. LF-NMR’s ability to noninvasively quantify the total water and oil content, differentiate between bound and mobile phases, and measure the SARA fractions underscores its superiority over traditional analysis methods, which often suffer from interference and lack of precision. This manuscript not only highlights LF-NMR’s pivotal role in enhancing crude-oil characterization but also reviews recent developments that solidify its position as an indispensable tool in the petroleum industry. The convergence of empirical studies and technological advancements points toward a pressing need for further research to fully exploit LF-NMR’s potential and refine its application, ensuring its continued contribution to the efficient and accurate analysis of petroleum products.
Integrated Approach for Offshore Wind Turbine Site Selection: Implications for Sustainability in Power Supply Chain
Authors: Karuppiah Koppiahraj , Sankaranarayanan Bathrinath , Ali Syed Mithun , Marimuthu Uthayakumar
Published: July 2024

Offshore wind turbine (OWT), a sustainable energy source, has recently gained wide attention. The energy demand for India is soaring high as it is a fast-developing nation in terms of industrialization; however, the interest shown by India toward renewable energy is low, especially for OWTs. This study aims to identify, categorize, and evaluate the criteria needed to be considered in the installation of OWTs and selection of potential locations in India. Based on literature analysis and exploratory interviews with experts, six aspects, namely, climatic conditions, regional features, investments and benefits, environmental impact, economic impact, and social and technical impact, with a total of twenty-six criteria, were identified and evaluated. An integrated approach of data envelopment analysis (DEA) with grey analytical hierarchy process (GAHP) and grey Complex proportional assessment (GCOPRAS) is used to evaluate the criteria and also to identify the locations for OWTs. Soil condition, extreme wind speed, seismic movement, tidal flow, and closeness to the power transmission grid have been identified as the top five criteria to be considered in the installation of OWTs. Gujarat, Tamil Nadu, Odisha, the Lakshadweep Islands, and the Andaman and Nicobar Islands have been identified as potential locations for installing OWTs in India. The outcomes of this study will deliver better insights for the practitioners about the criteria that need to be considered in OWTs. Further, this study sheds light on the importance of OWTs in an Indian context, which can possibly attract more investments.
On the Dynamics of Spot Power Prices across Western Europe in Pandemic Times
Authors: Abadie Luis María , Chamorro José Manuel
Published: July 2024

Learning the dynamics of power prices in a given market is important for a number of players (e.g., producers, consumers, and policy makers) at both macro- and microeconomic levels. This paper analyzes the recent behavior of spot prices in eight Western European countries. The sample period coincides with the COVID-19 pandemic for the most part: it starts in April 2020 and runs until May 2023; it includes the start of the Russia–Ukraine war. We introduce a new model for the hourly spot price of electricity. The deterministic component includes yearly, weekly, and daily seasonalities; the stochastic component accounts for volatility, mean reversion, and discrete jumps. We estimate the model with publicly available hourly data. Regarding the development of the internal market for electricity, we find that core mainland power markets now move closer in step with one another than before, but the integration process of the Iberian Peninsula seems to have kicked into reverse. As for the dynamics of power prices, in the last part of the sample period the speed of reversion falls everywhere, and price volatility increases noticeably; the expected number of jumps per hour decreases, but their average size turns to positive and they become more volatile.
Study on Heat and Mass Transfer Performance of Ultra-Thin Micro-Heat Pipes
Authors: Xiang Yuming , Sun Yonghua , Li Guolin , Liu Xiangjuan , Liu Lin , Zhao Fangwei , Li Xibing
Published: July 2024

With increased heat control requirements for high-heat-flux products in a narrow heat dissipation space, the ultra-thin micro-heat pipe (MHP) with high heat transfer performance has become an ideal heat dissipation component. In this study, the computational fluid dynamics (CFD) method is used to conduct three-dimensional modeling based on the geometric structure characteristics of an ultra-thin MHP. The capillary pressure of the sintered wick is represented by the modified parameter, and a simple and valuable heat and mass transfer model of the ultra-thin MHP is established by fitting the real experimental data through parameter modification. The flow situation of the working medium inside the ultra-thin MHP is analyzed based on the abovementioned parameters. The results show that when the modified parameter is α = 1.5, the temperature equalization requirements of the ultra-thin MHP can be met to the best degree. Moreover, with an increase in heating power, the error value between the surface temperature data of the model and the experimental data of the ultra-thin MHP sample decreases. Under different heating powers, the working medium inside the ultra-thin MHP has the same flow trend. In addition, a 40% increase in temperature difference is found at the junction of the heating section and the adiabatic section, leading to a fluctuation in the temperature gradient on the heat pipe surface. The research results provide a theoretical basis for the model establishment, heat and mass transfer performance investigation, and parameter optimization of ultra-thin MHPs.
Quality Assessment of Greek-Style Set Yoghurt Fortified with Extracted and Dried Australian Native Fruit, Illawarra Plum
Authors: McCullum Rebecca , Saifullah Md , Bowyer Michael , Vuong Quan
Published: July 2024

The Illawarra plum (IP) is native to Australia and has been used as a bush food for centuries. With rich phytochemicals and natural pigments, IP has the potential to be an added ingredient to improve the physicochemical properties of food, including yoghurt. This study prepared dried IP powders through vacuum drying (VD) and freeze drying (FD), produced extracts from these dried powders, and fortified them into Greek-style set yoghurt. The changes in colour, pH, titratable acidity (TA), syneresis, total soluble solids (TS), and phytochemicals were measured throughout a chilled storage period of 28 days. The results showed that FD and FD extract could provide a stable, distinct pink colour to yoghurt. IP powders and their extracts improved TS content and, thus, the consistency of yoghurt. Compared to the control, VD, FD, and FD extract of IP did not significantly affect the level of acidity or syneresis after 28 days of chilled storage. Yoghurt fortified with FD and FD extract had the greatest level of phenolics, anthocyanins, and radical scavenging antioxidant activities. This study revealed that IP powders and their extracts can positively improve the physicochemical properties of Greek-style set yoghurt. FD powder is recommended over its extract to fortify this yoghurt, as it can be cost-effectively prepared by freeze drying and then grinding the fresh fruit into powder. Future studies are needed to evaluate other variables in yoghurt preparation, including the concentration of IP and strains of yoghurt culture. Further, the consumer perception of sensory quality and acceptability of yoghurt fortified with FD IP powder should be investigated.
Rapid Determination of Crude Protein Content in Alfalfa Based on Fourier Transform Infrared Spectroscopy
Authors: Du Haijun , Zhang Yaru , Ma Yanhua , Jiao Wei , Lei Ting , Su He
Published: July 2024

The crude protein (CP) content is an important determining factor for the quality of alfalfa, and its accurate and rapid evaluation is a challenge for the industry. A model was developed by combining Fourier transform infrared spectroscopy (FTIS) and chemometric analysis. Fourier spectra were collected in the range of 4000~400 cm−1. Adaptive iteratively reweighted penalized least squares (airPLS) and Savitzky–Golay (SG) were used for preprocessing the spectral data; competitive adaptive reweighted sampling (CARS) and the characteristic peaks of CP functional groups and moieties were used for feature selection; partial least squares regression (PLSR) and random forest regression (RFR) were used for quantitative prediction modelling. By comparing the combined prediction results of CP content, the predictive performance of airPLST-cars-PLSR-CV was the best, with an RP2 of 0.99 and an RMSEP of 0.053, which is suitable for establishing a small-sample prediction model. The research results show that the combination of the PLSR model can achieve an accurate prediction of the crude protein content of alfalfa forage, which can provide a reliable and effective new detection method for the crude protein content of alfalfa forage.
Daily Supplementation with Bifidobacterium longum KACC91563 Alleviates Allergic Contact Dermatitis in an Animal Model
Authors: Hoa Van-Ba , Park So-Hyun , Ha Do-Hyun , Son Je-Hee , Lee Kil-Ho , Park Won-Seo , Yoo Ja-Yeon , Bae In-Seon , Kim Hyoun-Wook , Kang Han-Byul , Lee Sang-Myeong , Ham Jun-Sang
Published: July 2024

Allergic contact dermatitis (ACD) is the most common chronic inflammatory skin disease (or immune-mediated disease), causing disruption to our psychological condition and life quality. In this study, the therapeutic properties of probiotic Bifidobacterium longum (B. longum) was investigated by using an ACD-induced animal model. For ACD induction, BALB/c mice ear and dorsal skin were sensitized with 240 µL of 1% (w/v) 2,4-dinitrochlorobenzene (DNCB) twice (3-day intervals). After a week of the first induction, the mice were re-sensitized by painting on their dorsal skin and ear with 0.4% (w/v) DNCB for a further three times (once per week). Before the ACD induction of 2 weeks and throughout the trial period, the BALB/c mice were supplemented daily with 1 mL of 1.0 × 109 CFU or 5.0 × 109 CFU B. longum using an intragastric gavage method. The ACD-induced mice without B. longum supplementation were used as a control. Results show that B. longum supplementation significantly alleviated ACD symptoms (e.g., ear swelling, epidermal damage) and immune response (e.g., reduced immune cell recruitment, serum IgE level, and cytokine production). The therapeutic efficiency of B. longum increased as the supplementation dose increased. Thus, daily supplementation with 5.0 × 109 CFU probiotic B. longum could be an effective method for the prevention and treatment of ACD.
Effects of Transglutaminase-Induced β-Conglycinin Gels on Intestinal Morphology and Intestinal Flora in Mice at Different High-Intensity Ultrasound Pretreatment Time
Authors: Zhang Jixin , Zhang Lan , Xu Huiqing , Wang Jun
Published: July 2024

TGase-7S gels prepared after different HIU pretreatment times were used to intervene in healthy mice to analyze their effects on growth characteristics and intestinal morphology, and 16S rRNA high-throughput sequencing was applied to fecal samples to investigate the effects of the gel on the structure and diversity of intestinal flora in mice. The results showed that the intestinal tissues of mice in different treatment groups showed better integrity, and the intake of gel increased the length of small intestinal villi in mice, among which the 30-gel group had the highest value of villi length (599.27 ± 44.28) μm (p < 0.05) and showed the neatest and tightest arrangement, indicating that the intake of gel did not have adverse effects on the intestinal tract. The effect of gel ingestion on the diversity of the intestinal microbial community structure was more significant, positively promoting the growth of beneficial bacteria such as Desferriobacterium, Synechococcus, and Bifidobacterium. In addition, the ingestion of the gel improved the intestinal health of mice by altering the physiological functions of the intestinal flora and modulating their participation in various metabolic pathways. The above findings provide some theoretical value for the safety of 7S gel in food applications.
Derivation of Closed-Form Expressions in Apéry-like Series Using Fractional Calculus and Applications
Authors: Duangpan Ampol , Boonklurb Ratinan , Rakwongwan Udomsak , Sutthimat Phiraphat
Published: July 2024

This paper explores the Apéry-like series and demonstrates the derivation of closed-form expressions using fractional calculus. We consider a variety of Apéry-like functions, which were categorized by their functional forms and coefficients by applying the Riemann–Liouville fractional integral and derivative to examine their properties across various domains. The study focuses on establishing rigorous mathematical frameworks that unveil new insights into the behaviors of these series, contributing to a deeper understanding of number theory and mathematical analysis. Key results include proofs of convergence and divergence within specified intervals and the derivation of closed-form solutions through fractional integration and differentiation. This paper also introduces a method aimed at conjecturing mathematical constants through continued fractions as an application of our results. Finally, we provide the proof of validation for three unproven conjectures of continued fractions obtained from the Ramanujan Machine.
Sequential Impact of Diabetes Mellitus on Deep Neck Infections: Comparison of the Clinical Characteristics of Patients with and without Diabetes Mellitus
Authors: Liao Ting-I , Ho Chia-Ying , Chin Shy-Chyi , Wang Yu-Chien , Chan Kai-Chieh , Chen Shih-Lung
Published: July 2024

Background: Deep neck infections (DNIs) can compromise the airway and are associated with high morbidity and mortality rates. Diabetes mellitus (DM) is a metabolic disorder characterized by chronic hyperglycemia that is associated with several comorbidities. We compared the clinical characteristics of DNI patients with and without DM. Methods: This study recorded the relevant clinical variables of 383 patients with DNIs between November 2016 and September 2022; of those patients, 147 (38.38%) had DM. The clinical factors between DNI patients with and without DM were assessed. Results: Patients with DM were older (p < 0.001), had higher white blood cell counts (p = 0.029) and C-reactive protein levels (CRP, p < 0.001), had a greater number of deep neck spaces (p = 0.002) compared to patients without DM, and had longer hospital stays (p < 0.001). Klebsiella pneumoniae was cultured more frequently from patients with DM than those without DM (p = 0.002). A higher CRP level (OR = 1.0094, 95% CI: 1.0047–1.0142, p < 0.001) was a significant independent risk factor for DM patients with prolonged hospitalization. The lengths of hospital stays in patients with poorly controlled DM were longer than those with well-controlled DM (p = 0.027). Conclusions: DNI disease severity and outcomes were worse in patients with DM than those without DM. Antibiotics effective against Klebsiella pneumoniae should be used for DNI patients with DM. DNI patients with DM and high CRP levels had more prolonged hospitalizations. Appropriate blood glucose control is essential for DNI patients with DM.
Multifaceted Impact of CO2 Laser Therapy on Genitourinary Syndrome of Menopause, Vulvovaginal Atrophy and Sexual Function
Authors: Jankovic Svetlana , Rovcanin Marija , Zamurovic Milena , Jovanovic Branka , Raicevic Tatjana , Tomic Ana
Published: July 2024

Genitourinary syndrome of menopause (GSM) encompasses a range of distressing symptoms in the vulvovaginal and/or bladder–urethral regions related to menopause changes, negatively influencing woman’s quality of life and sexual activity. Fractional micro-ablative CO2 laser therapy has shown the potential to reinstate the vaginal epithelium to a condition akin to the premenopausal state, thereby ameliorating the subjective symptoms associated with GSM. We conducted a prospective, pilot study in 73 sexually active postmenopausal women treated with CO2 laser for their GSM symptoms, while assessing Vaginal Health Index Score (VHIS) and sexual function through the Female Sexual Function Index (FSFI) Questionnaire. The laser treatment resulted in a decrease in VHIS and patient-reported vulvovaginal atrophy (VVA) symptoms, with a significantly lower prevalence of vaginal itching, dryness, and burning (p < 0.001), as well as dyspareunia (p = 0.002). The occurrence of urinary incontinence, urgency, and vaginal heaviness significantly reduced, with an improvement in the staging of cystocele, either to Stage 1 or complete resolution (p < 0.001). FSFI total and domain scores were significantly higher after the treatment, indicating better sexual function, with a post-treatment score median of 25 (p < 0.001). Therefore, using a three-cycle fractional CO2 laser was an effective choice for reducing urogenital discomfort related to GSM in postmenopausal women.
Unveiling the Moderating Factors in the Relationship between Physical Activity and Health-Related Quality of Life among University Students during COVID-19: A Mixed Study Design
Authors: Mortada Eman M. , Al Awaji Nisreen N. , Zaidi Uzma , Aldhahi Monira I. , Alsaleh Hadel , Alroqaiba Nouf , Awad Salwa S.
Published: July 2024

This study examines the moderating effects of various factors on the relationship between physical activity (PA) and health-related quality of life (HRQoL) among 287 female college students during the COVID-19 pandemic. Data were collected through an online questionnaire covering health issues, PA, self-esteem, HRQoL, and sociodemographic information, supplemented by semi-structured interviews and focus groups with six participants. Results showed that 46% of respondents had good HRQoL, and 38% were physically active. The interactions of age, socioeconomic status (SES), and academic performance with PA on HRQoL were insignificant. However, physical and mental health problems significantly moderated the PA–HRQoL relationship, accounting for 1% and 4% of the variance, respectively. The qualitative analysis highlighted the need for student activity clubs and mental health support to enhance coping strategies and overall HRQoL. In conclusion, age and SES did not moderate the PA–HRQoL relationship, while physical and mental health issues did. Programs targeting students with health problems are crucial to improving their physical and mental health, thereby enhancing their well-being.
Analysis of Endodontic Successes and Failures in the Removal of Fractured Endodontic Instruments during Retreatment: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis
Authors: Dioguardi Mario , Dello Russo Corrado , Scarano Filippo , Esperouz Fariba , Ballini Andrea , Sovereto Diego , Alovisi Mario , Martella Angelo , Lo Muzio Lorenzo
Published: July 2024

This study presents a systematic review with meta-analysis to evaluate the success rates of endodontic retreatments in teeth where separated instruments are located within the roots. The search and selection of studies were conducted across two databases, SCOPUS and PubMed, as well as the Cochrane Library registry, yielding a total of 1620 records. Following the selection process, 11 studies were included in the systematic review. Overall, out of 1133 retreated teeth, there were 172 failures in instrument removal and 55 perforations. The meta-analysis results indicate that failures are more frequent when instruments are located in the apical third, with a failure rate of 21%, compared to an 8.8% failure rate in the middle/coronal third. The anatomy of the root canals, particularly the location of the separated instruments, significantly influences the success rates.
Bixafen, Prothioconazole, and Trifloxystrobin Alone or in Combination Have a Greater Effect on Health Related Gene Expression in Honey Bees from Nutritionally Deprived than from Protein Supplemented Colonies
Authors: Kato Aline Y. , Freitas Tainá A. L. , Gomes Cássia R. A. , Alves Thais R. R. , Ferraz Yara M. M. , Trivellato Matheus F. , De Jong David , Biller Jaqueline D. , Nicodemo Daniel
Published: July 2024

The aim of this study was to evaluate whether alterations in food availability compromise the metabolic homeostasis of honey bees exposed to three fungicides alone or together. Ten honey bee colonies were used, with half receiving carbohydrate-protein supplementation for 15 weeks while another five colonies had their protein supply reduced with pollen traps. Subsequently, forager bees were collected and exposed by contact to 1 or 7 µg of bixafen, prothioconazole, or trifloxystrobin, either individually or in combination. After 48 h, bee abdomens without the intestine were used for the analysis of expression of antioxidant genes (SOD-1, CAT, and GPX-1), detoxification genes (GST-1 and CYP306A1), the storage protein gene vitellogenin, and immune system antimicrobial peptide genes (defensin-1, abaecin, hymenoptaecin, and apidaecin), through real-time PCR. All fungicide treatments induced changes in gene expression, with bixafen showing the most prominent upregulation. Exposure to 1 µg of each of the three pesticides resulted in upregulation of genes associated with detoxification and nutrition processes, and downregulation of immune system genes. When the three pesticides were combined at a dose of 7 µg each, there was a pronounced downregulation of all genes. Food availability in the colonies affected the impact of fungicides on the expression of the studied genes in forager bees.