bluuebunny/crossref_metadata_2025 huggingface dataset:
Benefits and Challenges of Collaboration between Students and Conversational Generative Artificial Intelligence in Programming Learning: An Empirical Case Study
Authors: Yan Wanxin , Nakajima Taira , Sawada Ryo
Published: April 2024

The utilization of conversational generative artificial intelligence (Gen AI) in learning is often seen as a double-edged sword that may lead to superficial learning. We designed and implemented a programming course focusing on collaboration between students and Gen AI. This study explores the dynamics of such collaboration, focusing on students’ communication strategies with Gen AI, perceived benefits, and challenges encountered. Data were collected from class observations, surveys, final reports, dialogues between students and Gen AI, and semi-structured in-depth interviews. The results showed that effective collaboration between students and Gen AI could enhance students’ meta-cognitive and self-regulated learning skills and positively impact human-to-human communication. This study further revealed the difficulties and individual differences in collaborating with Gen AI on complex learning tasks. Overall, collaborating with Gen AI as a learning partner, rather than just a tool, enables sustainable and independent learning, beyond specific learning tasks at a given time.
Cognitive Profiles in Preschool Children at Risk for Co-Occurring Dyslexia and ADHD
Authors: Kellens Silke , Baeyens Dieter , Ghesquière Pol
Published: April 2024

Developmental dyslexia and attention-deficit/hyperactivity disorder (ADHD) co-occur in 15–40% of individuals diagnosed with one disorder. Despite substantial research on the cognitive profiles of preschoolers at risk for either dyslexia or ADHD, studies have neglected children at risk for co-occurring dyslexia and ADHD. Thus, our study compared the cognitive profile of preschoolers at risk for dyslexia with the profile of children at risk for co-occurring dyslexia and ADHD. We assessed 50 preschoolers at dyslexia risk (DR), 50 at dyslexia + ADHD risk (DAR), and 48 without risk (NR) (Mage = 67 months). Our assessment encompassed phonological processing, executive functioning (EF), receptive vocabulary, and processing speed. Principal component analysis revealed two distinct components within the measures of EF, a verbal short-term memory and an EF component. ANOVA revealed that the NR group outperformed risk groups across measures, except for cognitive flexibility and delay of gratification. Notably, the DR and DAR groups did not differ in most measures but showed near-significant differences on the EF component, with the DR group having higher composite scores than the DAR group. In conclusion, ADHD risk did not impact the cognitive performance of children at risk for dyslexia but might amplify EF problems that at-risk preschoolers encounter.
Academic Satisfaction and Meaning in Life: The Mediating Roles of Personal Growth Initiative and Career Adaptability
Authors: Li Tiantian , Tien Hsiu-Lan Shelley , Wang Juanjuan
Published: April 2024

The present study examined the relationship between academic satisfaction and meaning in life. To further explain the relationship between these factors, we examined personal growth initiative and career adaptability as mediator variables. A total of 691 undergraduate students were invited as participants. They completed the following four inventories: the Meaning in Life Scale, the Academic Satisfaction Scale, the Career Adaptability Scale, and the Personal Growth Initiative Scale. The results indicated the following: (a) Chinese undergraduate students’ academic satisfaction could positively predict their presence of meaning in life and search for meaning in life. (b) The relationship between academic satisfaction and presence of meaning in life among Chinese undergraduate students was mediated by personal growth initiative and career adaptability, but the relationship between academic satisfaction and searching for meaning in life among Chinese undergraduate students was only mediated by personal growth initiative. This study demonstrated that academic satisfaction promoted meaning in life not only directly but also indirectly through the mediating effect of personal growth initiative and career adaptability.
Role of Physical Activities during Working Hours in Promoting Planetary Health
Authors: Tapani Annukka , Östring Elina , Sinkkonen Merja
Published: April 2024

Work can be a source of a meaningful life and well-being. It can also be a source of stress and mental illness. The trends concerning working life development involve intensification and individualisation, and, at the same time, the demands of expertise work are such that they need collaborative actions. With respect to well-being, there is a need for individuals to see themselves members of the community. In this study, we identified vocational education staff types by studying the connections between physical activities and experienced workload. The data were collected by using empathy-based stories. The method of analysing the data can be described as a discursive–narrative approach based on qualitative and thematic content analyses. Based on the data, four story types were established: Forerunner, Exhausted, Leisure-Time Enthusiast, and Thinker. Individual conceptions of breaks, workload, free time, and awareness of one’s well-being were found to be important in the creation of a healthy working life. There is a need to discuss realistic work demands in the vocational education context. Education and active teacher members could be key actors in achieving sustainability goals and improving planetary health.
Intelligent Security Authentication for Connected and Autonomous Vehicles: Attacks and Defenses
Authors: Qiu Xiaoying , Yu Jinwei , Jiang Wenbao , Sun Xuan
Published: April 2024

The emergence of integrated positioning, communication, and sensing technologies has paved the way for a surge in connected and autonomous vehicles. The control system has been successful in reliable and fast transmission. However, practical applications face security risks, especially data tampering and spoofing attacks. To improve the resilience of the system against potential attacks, we attempt to leverage a generative adversarial network learning-assisted authentication framework (GAF). In addition to proposing a new method for validating vehicles, we also introduce a new architectural innovation in the generator–discriminator pair to achieve improved results. The generator sub-network is constructed using an advanced convolutional neural network, whereas the discriminator is designed to leverage global and local information to determine whether a signal is real or fake. On this basis, we propose a signal enhancement-based authentication method, a deep convolutional generative adversarial network (DCGAN). Experimental results using the National Institute of Standards and Technology (NIST) dataset show that the proposed method is effective in denoising and improving the detection performance.
Classification of Microscopic Hyperspectral Images of Blood Cells Based on Lightweight Convolutional Neural Network
Authors: Fang Jinghui
Published: April 2024

Hyperspectral imaging has emerged as a novel imaging modality in the medical field, offering the ability to acquire images of biological tissues while simultaneously providing biochemical insights for in-depth tissue analysis. This approach facilitates early disease diagnosis, presenting advantages over traditional medical imaging techniques. Addressing challenges such as the computational burden of existing convolutional neural networks (CNNs) and imbalances in sample data, this paper introduces a lightweight GhostMRNet for the classification of microscopic hyperspectral images of human blood cells. The proposed model employs Ghost Modules to replace conventional convolutional layers and a cascading approach with small convolutional kernels for multiscale feature extraction, aiming to enhance feature extraction capabilities while reducing computational complexity. Additionally, an SE (Squeeze-and-Excitation) module is introduced to selectively allocate weights to features in each channel, emphasizing informative features and efficiently achieving spatial–spectral feature extraction in microscopic hyperspectral imaging. We evaluated the performance of the proposed GhostMRNet and compared it with other state-of-the-art models using two real medical hyperspectral image datasets. The experimental results demonstrate that GhostMRNet exhibits a superior performance, with an overall accuracy (OA), average accuracy (AA), and Kappa coefficient reaching 99.965%, 99.565%, and 0.9925, respectively. In conclusion, the proposed GhostMRNet achieves a superior classification performance at a smaller computational cost, thereby providing a novel approach for blood cell detection.
Multi-Strategy Improved Particle Swarm Optimization Algorithm and Gazelle Optimization Algorithm and Application
Authors: Qin Santuan , Zeng Huadie , Sun Wei , Wu Jin , Yang Junhua
Published: April 2024

In addressing the challenges associated with low convergence accuracy and unstable optimization results in the original gazelle optimization algorithm (GOA), this paper proposes a novel approach incorporating chaos mapping termed multi-strategy particle swarm optimization with gazelle optimization algorithm (MPSOGOA). In the population initialization stage, segmented mapping is integrated to generate a uniformly distributed high-quality population which enhances diversity, and global perturbation of the population is added to improve the convergence speed in the early iteration and the convergence accuracy in the late iteration. By combining particle swarm optimization (PSO) and GOA, the algorithm leverages individual experiences of gazelles, which improves convergence accuracy and stability. Tested on 35 benchmark functions, MPSOGOA demonstrates superior performance in convergence accuracy and stability through Friedman tests and Wilcoxon signed-rank tests, surpassing other metaheuristic algorithms. Applied to engineering optimization problems, including constrained implementations, MPSOGOA exhibits excellent optimization performance.
A Ka-Band Two-Channel Two-Beam Receiver Based on a Substrate-Integrated Suspended Line
Authors: Xu Hui , Ma Kaixue , Li Shuantao , Liu Gaojian , Wang Yongqiang
Published: April 2024

To realize the miniaturization and high performance for the key transceiver components of a phased array antenna, we proposed a two-channel two-beam receiver based on a substrate-integrated suspended-line (SISL). Multi-layer composite substrate printing circuit is used in the SISL structure to replace the metal cavity and passive circuits. The active components are placed in the air cavity in the SISL structure. The substrates forming the cavity are soldered together to ensure the hermetic seal and high performance. The SISL circuits have the advantage of low loss, low cost, light weight, self-packaging, and high inter-channel isolation. The proposed Ka-band two-channel two-beam receiver shows a gain of >28 dB, a noise figure of <2.6 dB, with functions of 6-bit phase shifting and attenuation.
Guest Editorial: Foreword of the Special Issue on Real-World Applications of Machine Learning
Authors: Rizvi Syed Tahir Hussain , Arif Arslan
Published: April 2024

Machine learning is an ever-growing field, and many real-time applications are utilized in daily life [...]
Light-Emitting Diodes for Energy Harvesting
Authors: Colace Lorenzo , Assanto Gaetano , De Iacovo Andrea
Published: April 2024

Energy harvesting is gaining substantial relevance in the realm of ultra-low-power electronics and Internet-of-Things devices with limited access to classic power sources. Several harvesting approaches are available, depending on the energy source; among them, photovoltaic devices benefit from the highest energy density. However, the inclusion of a dedicated photovoltaic cell in a low-power system may result in increased costs and complexity, thus hampering economic sustainability. Conversely, electronic apparatuses often make use of light-emitting-diodes (LEDs), which could be effectively employed as photovoltaic energy harvesters whenever not actively generating photons. Here, we explore the potentials of commercially available LEDs for energy harvesting and determine their quantum efficiency. We examine the correlation of the latter with the spectral response and the available light, demonstrating that visible-wavelength diode emitters can yield very high conversions in the photovoltaic mode. We report measured quantum efficiencies as high as 39% under low-intensity (100 µW/cm2) fluorescent illumination.
Shared Knowledge Distillation Network for Object Detection
Authors: Guo Zhen , Zhang Pengzhou , Liang Peng
Published: April 2024

Object detection based on Knowledge Distillation can enhance the capabilities and performance of 5G and 6G networks in various domains, such as autonomous vehicles, smart surveillance, and augmented reality. The integration of object detection with Knowledge Distillation techniques is expected to play a pivotal role in realizing the full potential of these networks. This study presents Shared Knowledge Distillation (Shared-KD) as a solution to overcome optimization challenges caused by disparities in cross-layer features between teacher–student networks. The significant gaps in intermediate-level features between teachers and students present a considerable obstacle to the efficacy of distillation. To tackle this issue, we draw inspiration from collaborative learning in real-world education, where teachers work together to prepare lessons and students engage in peer learning. Building upon this concept, our innovative contributions in model construction are highlighted as follows: (1) A teacher knowledge augmentation module: this module is proposed to combine lower-level teacher features, facilitating the knowledge transfer from the teacher to the student. (2) A student mutual learning module is introduced to enable students to learn from each other, mimicking the peer learning concept in collaborative learning. (3) The Teacher Share Module combines lower-level teacher features: the specific functionality of the teacher knowledge augmentation module is described, which involves combining lower-level teacher features. (4) The multi-step transfer process can be easily optimized due to the minimal gap between the features: the proposed approach breaks down the knowledge transfer process into multiple steps, which can be easily optimized due to the minimal gap between the features involved in each step. Shared-KD uses simple feature losses without additional weights in transformation, resulting in an efficient distillation process that can be easily combined with other methods for further improvement. The effectiveness of our approach is validated through experiments on popular tasks such as object detection and instance segmentation.
Advanced Interference Mitigation Method Based on Joint Direction of Arrival Estimation and Adaptive Beamforming for L-Band Digital Aeronautical Communication System
Authors: Wang Lei , Hu Xiaoxiao , Liu Haitao
Published: April 2024

The L-band digital aeronautical communication system (LDACS) is one of the candidate technologies for future broadband digital aeronautical communications, utilizing the unused L-band spectrum between distance measuring equipment (DME) channels. However, the higher signal power of DME complicates LDACS implementation. This paper proposes an advanced DME mitigation approach for the LDACS, integrating joint direction of arrival (DOA) estimation with adaptive beamforming techniques. The proposed method begins by exploiting the cyclostationary characteristics of signals, accurately obtaining the preliminary direction of the LDACS signal using the Cyclic-MUSIC method. Subsequent precise steering vectors (SVs) are selected through Capon spectrum search, followed by the reconstruction of the interference plus noise covariance matrix (INCM). Using the obtained SV and INCM, the weight vector is calculated and beamforming is performed. Simulation results validate that the proposed method not only accurately estimates the direction of LDACS signal but also efficiently mitigates DME interference, demonstrating a superior performance and reduced algorithmic complexity, even in scenarios with lower signal-to-noise ratios (SNRs) and the presence of DOA estimation errors. Additionally, the proposed method achieves a low bit error rate (BER), further validating its ability to ensure communication quality and enhance the reliability of LDACS.
The Characterization of the Key Aroma Compounds in Non-Smoked Bacon by Instrumental and Sensory Methods
Authors: Wu Han , He Zhifei , Yang Li , Li Hongjun
Published: April 2024

The aroma profiles in non-smoked bacon were investigated via GC–O–MS, GC × GC–TOFMS, and GC–IMS. GC-O-MS is advantageous for detecting aldehydes. GC × GC-TOFMS is more sensitive to hydrocarbons and alcohols, while GC-IMS detects a balanced range of categories. Only 9 of the 239 detected volatiles were identifiable by all three methods. Therefore, the combination of all three methods proved to be the most effective way to comprehensively analyze the aroma profiles of bacon. Recombination and omission tests were performed using aroma compounds with a flavor dilution (FD) factor greater than 27; five volatiles were identified as key aroma compounds in non-smoked bacon, including hexanal, (E,E)-2,4-decadienal, 1-octen-3-ol, dihydro-5-pentyl-2(3H)-furanone, and 3-methyl-butanoic acid. Among these, hexanal and 1-octen-3-ol exhibited relatively high FD factors and odor activity values (OAVs), so they were confirmed as the primary contributors. Meanwhile, seven volatiles contributed to the unique aroma of non-smoked bacon in different regions. The difference in the aroma of bacon in different regions is mainly due to the content of various volatiles rather than the type. A comprehensive analysis of the aroma in non-smoked bacon can reveal theoretical information for improving the process and quality control of the product.
Chemical Compositions and Characteristics of Biocalcium from Pre-Cooked Tuna Bone as Influenced by Sodium Chloride Pretreatment and Defatting by Asian Seabass Lipase
Authors: Benjakul Soottawat , Pomtong Saowakon , Chedosama Afeefah , Saetang Jirakrit , Sookchoo Pornsatit , Nilsuwan Krisana
Published: April 2024

Pre-cooked bone is a waste product generated during tuna processing and can serve as a potential source of biocalcium (BC). Generally, non-collagenous protein and fat must be removed properly from bone. A NaCl solution can be used to remove such proteins, while fish lipase can be used in a green process, instead of solvent, for fat removal. Thus, this study aimed to investigate the impact of NaCl pretreatment at different concentrations in combination with heat to eliminate non-collagenous proteins, and to implement fish lipase treatments at varying levels for fat removal, for BC production from pre-cooked tuna bone. Optimal NaCl pretreatment of bone was achieved when a 5% NaCl solution at 80 °C was used for 150 min. The lowest lipid content was obtained for bone defatted with crude lipase extract (CLE) at 0.30 Unit/g of bone powder for 2 h. BC powder from bone defatted with CLE (DF-BC) possessed greater contents of ash, calcium, and phosphorus and smaller particle sizes than the control BC powder. X-ray diffractograms suggested that both BC powders consisted of hydroxyapatite as a major compound, which had a crystallinity of 62.92–63.07%. An elemental profile confirmed the presence of organic and inorganic matter. Thus, BC powder could be produced from pre-cooked tuna bone using this ‘green process’.
Lost Food and Associated Phosphorus Footprint: Evidence from China
Authors: Gao Dengyun , Li Xing , Ma Junkai , Qian Long
Published: April 2024

The environmental impacts of excessive phosphorus emissions (PE) have been widely discussed in recent years. This study aims to calculate and evaluate the phosphorus footprint (PF) of food thrown away in Chinese universities. Based on a nationwide survey involving 9192 university students from 29 provinces and 29 universities in China, the result reveals that the PF generated by food waste in Chinese university canteens was 3.209 Kt in 2018. Furthermore, it is found that meal satisfaction, gender, regional economic level, dietary culture, and years of education all have significant impacts on lost food PF. Our findings emphasize the importance of reducing food waste in university canteens, which plays a crucial role in ensuring food security and environmental protection.
Decoding the Effect of Running on Flavor Perception Changes during Consumption of Sports Drinks
Authors: Pu Biwen , Meng Ruixin , Shi Yige , Pu Dandan
Published: April 2024

An online survey was conducted to show that most respondents preferred sports drinks with sweet and fruity characteristics. Eleven sports drinks with higher consumers’ preferences were further selected for aroma and taste evaluation. Temporal dominance of sensations analysis showed that fruity and fresh attributes were dominant, while sour and fruity sweet were dominant tastes during consumption. β-Damascenone, β-ionone, and linalool contributing to floral perception, γ-decalactone, ethyl cinnamate, and isoamyl acetate contributing to fruity perception, and menthol contributing to fresh perception were confirmed by odor activity value analysis. Running affected the nasal air flow and the saliva secretion, resulting in the flavor perception changing from fruity sweet, sweet, and fruity to sour because the recognition threshold decreased for sweet, fruity, floral, and fresh flavors and increased for saltiness, astringency, and sour tastes.
Exploring the Influence of Origin, Harvest Time, and Cultivation Method on Antioxidant Capacity and Bioactive Compounds of Matcha Teas
Authors: Jakubczyk Karolina , Szymczykowska Kinga , Kika Joanna , Janda-Milczarek Katarzyna , Palma Joanna , Melkis Klaudia , Alshekh Rami , Maciejewska-Markiewicz Dominika
Published: April 2024

Matcha, or powdered green tea, has been gaining popularity and is no longer consumed only in the form of infusions, finding new uses in gastronomy and the food industry. The range of teas available on the food market has expanded considerably; hence, the aim of this study was to determine, for the first time, the antioxidant capacity and contents of antioxidant compounds in various Matcha teas available on the Polish market, taking into account the country of origin, time of harvest, and conventional vs. organic cultivation. Eleven green-tea powders were used in the analyses performed using spectrophotometric methods (Trolox equivalent antioxidant capacity, Ferric-Ion-Reducing Antioxidant Power, Total Polyphenol Content, Total Flavonoid Content, Vitamin C Content) and HPLC methods (polyphenolic acids, flavonoids, and caffeine). Antioxidant capacity ranged from 7.26 to 9.54 mM Trolox equivalent/L while reducing power ranged from 1845.45 to 2266.12 Fe(II)/L. Total phenolic content amounted to 820.73–1017.83 mg gallic acid equivalent/L, and total flavonoid content was 864.71–1034.40 mg rutin equivalent /L. A high vitamin C content was found, ranging from 38.92 to 70.15 mg/100 mL. Additionally, a high content of caffeine that ranged between 823.23 and 7313.22 mg/L was noted. Moreover, a high content of polyphenolic compounds, including epicatechin gallate, myricetin, gallic acid, and 4—hydroxybenzoic acid, was found. The phytochemical composition and antioxidant properties depended on the harvest time, type of cultivation, and country of origin. Therefore, Matcha tea infusions have been shown to be a valuable source of antioxidants that can be used in the daily diet.
Effect of Neutral Protease on Freshness Quality of Shucked Pacific Oysters at Different Storage Conditions
Authors: Su Lanxiang , Yang Wenge , Liu Siyang , Yuan Chunhong , Huang Tao , Jia Ru , Wei Huamao
Published: April 2024

The aim of this study was to investigate the effect of neutral protease treatment on the biochemical properties of various parts of Pacific oysters (Crassostrea gigas) under different storage conditions. The mechanism of quality degradation in the mantle, adductor muscle, gill, and trunk of treated oysters stored at −1.5 °C (superchilling) or 4 °C (refrigeration) for several days using different storage methods was studied. The results showed that the oyster treated with the enzyme exhibited higher glycogen content, flavor nucleotide content, and sensory scores compared to the control group. Superchilling at −1.5 °C was observed to slow the increase in total volatile basic nitrogen (TVB-N), total viable count (TVC), and pH, while maintaining sensory scores better than refrigeration at 4 °C. Both wet superchilling (WS) and dry exposed superchilling (DeS) methods effectively preserved freshness and quality at −1.5 °C. The freshness of the oysters’ body trunk changed most significantly. K value, K′ value, and AEC value, as the evaluation indexes of oyster freshness, were affected by the storage medium. Therefore, neutral protease enhances the flavor of oysters in a short time, and oysters stored in wet superchilling or dry exposed superchilling conditions have an extended shelf life.
Widely Targeted Metabolomics and Network Pharmacology Reveal the Nutritional Potential of Yellowhorn (Xanthoceras sorbifolium Bunge) Leaves and Flowers
Authors: Sha Haojie , Li Shouke , Li Jiaxing , Zhao Junying , Su Dingding
Published: April 2024

Yellowhorn (Xanthoceras sorbifolium Bunge) is a unique oilseed tree in China with high edible and medicinal value. However, the application potential of yellowhorn has not been adequately explored. In this study, widely targeted metabolomics (HPLC-MS/MS and GC-MS) and network pharmacology were applied to investigate the nutritional potential of yellowhorn leaves and flowers. The widely targeted metabolomics results suggested that the yellowhorn leaf contains 948 non-volatile metabolites and 638 volatile metabolites, while the yellowhorn flower contains 976 and 636, respectively. A non-volatile metabolite analysis revealed that yellowhorn leaves and flowers contain a variety of functional components beneficial to the human body, such as terpenoids, flavonoids, alkaloids, lignans and coumarins, phenolic acids, amino acids, and nucleotides. An analysis of volatile metabolites indicated that the combined action of various volatile compounds, such as 2-furanmethanol, β-icon, and 2-methyl-3-furanthiol, provides the special flavor of yellowhorn leaves and flowers. A network pharmacology analysis showed that various components in the flowers and leaves of yellowhorn have a wide range of biological activities. This study deepens our understanding of the non-volatile and volatile metabolites in yellowhorn and provides a theoretical basis and data support for the whole resource application of yellowhorn.
Development of Germinated-Brown-Rice-Based Novel Functional Beverage Enriched with γ-Aminobutyric Acid: Nutritional and Bio-Functional Characterization
Authors: Jabeen Rifat , Jan Nusrat , Naseer Bazila , Sarangi Prakash Kumar , Sridhar Kandi , Dikkala Praveen Kumar , Bhaswant Maharshi , Hussain Syed Zameer , Inbaraj Baskaran Stephen
Published: April 2024

γ-aminobutyric acid (GABA), recognized as a primary inhibitory neurotransmitter within the brain, serves a crucial role in the aging process and in neurodegenerative conditions such as Alzheimer’s disease. Research has demonstrated the beneficial effects of GABA, particularly for elderly individuals. Given that elderly individuals often encounter challenges with swallowing food, beverages designed to address dysphagia represent a preferable option for this demographic. Among the different processing techniques, the germination process triggers biochemical changes, leading to an increase in certain nutrients and bioactive compounds (e.g., GABA). Therefore, we attempted to develop a novel functional beverage utilizing germinated brown rice enriched with GABA and studied its nutritional and bio-functional characterization. The optimal conditions (X1, X2, X3 and X4.) were determined: powdered sugar (40 g), chocolate powder (20 g), sodium carboxymethyl cellulose (0.5 g), GBR (220 g), and water (440 mL). The results of storage studies indicated that the germinated-brown-rice-based beverage exhibited favorable nutritional attributes, including increased γ-oryzanol (52.73 ± 1.56%), total phenolic content (26.68 ± 1.56 mg GAE/100 g), niacin (5.17 ± 0.14%), and GABA (42.12 ± 0.63 mg/100 g) levels. Additionally, the beverage demonstrated notable antioxidant activity (74.23 ± 2.37 µmol TE/100 g), suggesting potential health-promoting effects. Sensory evaluation revealed satisfactory acceptability among consumers, highlighting its palatability. Overall, this study elucidates the development of a novel functional beverage utilizing germinated brown rice enriched with GABA, offering promising nutritional and bio-functional characteristics for health-conscious consumers.
Robust Fractional-Order PI/PD Controllers for a Cascade Control Structure of Servo Systems
Authors: Chuong Vo Lam , Nam Ngo Hong , Giang Le Hieu , Vu Truong Nguyen Luan
Published: April 2024

In this paper, a cascade control structure is suggested to control servo systems that normally include a servo motor in coupling with two kinds of mechanism elements, a translational or rotational movement. These kinds of systems have high demands for performance in terms of fastest response and no overshoot/oscillation to a ramp function input. The fractional-order proportional integral (FOPI) and proportional derivative (FOPD) controllers are addressed to deal with those control problems due to their flexibility in tuning rules and robustness. The tuning rules are designed in the frequency domain based on the concept of the direct synthesis method and also ensure the robust stability of controlled systems by using the maximum sensitivity function. The M-Δ structure, using multiplicative output uncertainties for both control loops simultaneously, is addressed to justify the robustness of the controlled systems. Simulation studies are considered for two kinds of plants that prove the effectiveness of the proposed method, with good tracking of the ramp function input under the effects of the disturbances. In addition, the robustness of the controlled system is illustrated by a structured singular value (µ) plot in which its value is less than 1 over the frequency range.
Astrochemistry of the Molecular Gas in Dusty Star-Forming Galaxies at the Cosmic Noon
Authors: Perrotta Francesca , Torsello Martina , Giulietti Marika , Lapi Andrea
Published: April 2024

Far-infrared and submillimeter observations have established the fundamental role of dust-obscured star formation in the assembly of stellar mass over the past ∼12 billion years. At z = 2–4, the so-called “cosmic noon”, the bulk of star formation is enshrouded in dust, and dusty star-forming galaxies (DSFGs) contain ∼50% of the total stellar mass density. Star formation occurs in dense molecular clouds, and is regulated by a complex interplay between all the ISM components that contribute to the energy budget of a galaxy: gas, dust, cosmic rays, interstellar electromagnetic fields, gravitational field, and dark matter. Molecular gas is the actual link between star-forming gas and its complex environment: much of what we know about star formation comes from observations of molecular line emissions. They provide by far the richest information about the star formation process. However, their interpretation requires complex modeling of the astrochemical networks which regulate molecular formation and establish molecular abundances in a cloud, and a modeling of the physical conditions of the gas in which molecular energy levels become populated. This paper critically reviews the main astrochemical parameters needed to obtain predictions about molecular signals in DSFGs. Molecular lines can be very bright compared to the continuum emission, but radiative transfer models are required to properly interpret the observed brightness. We review the current knowledge and the open questions about the interstellar medium of DSFGs, outlining the key role of molecular gas as a tracer and shaper of the star formation process.
Polyhedral Oligomeric Sesquioxane Cross-Linked Chitosan-Based Multi-Effective Aerogel Preparation and Its Water-Driven Recovery Mechanism
Authors: Liu Yang , Ma Mingjian , Shen Yuan , Zhao Zhengdong , Wang Xuefei , Wang Jiaqi , Pan Jiangbo , Wang Di , Wang Chengyu , Li Jian
Published: April 2024

The use of environmentally friendly and non-toxic biomass-based interfacial solar water evaporators has been widely reported as a method for water purification in recent years. However, the poor stability of the water transport layer made from biomass materials and its susceptibility to deformation when exposed to harsh environments limit its practical application. To address this issue, water-driven recovery aerogel (PCS) was prepared by cross-linking epoxy-based polyhedral oligomeric silsesquioxane (EP-POSS) epoxy groups with chitosan (CS) amino groups. The results demonstrate that PCS exhibits excellent water-driven recovery performance, regaining its original volume within a very short time (1.9 s) after strong compression (ε > 80%). Moreover, PCS has a water absorption rate of 2.67 mm s−1 and exhibits an excellent water absorption capacity of 22.09 g g−1 even after ten cycles of absorption-removal. Furthermore, a photothermal evaporator (PCH) was prepared by loading the top layer with hydrothermally reacted tannins (HAs) and Zn2+ complexes. The results indicate that PCH achieves an impressive evaporation rate of 1.89 kg m−2 h−1 under one sun illumination. Additionally, due to the antimicrobial properties of Zn2+, PCH shows inhibitory effects against Staphylococcus aureus and Escherichia coli, thereby extending the application of solar water evaporators to include antimicrobial purification in natural waters.
New Tsunami Evacuation Training Methods: A Tsunami Evacuation Training Application
Authors: Arakawa Toshiya , Obayashi Fumiaki , Kobayashi Kazunobu , Itamiya Tomoki , Uno Shintaro , Yamabe Shigeyuki , Suzuki Takahiro
Published: April 2024

Despite evacuation on foot being recommended by authorities, evacuation in practice is assumed to include evacuation on foot and evacuation by car, as a certain amount of evacuation by car is to be expected. We developed a tsunami evacuation training application operating on smartphones and tablets, and a tsunami evacuation training simulator to evaluate the effect of this application. We then conducted an experiment in Nishio City to evaluate the application. We found that the subjects were able to quickly grasp the attention targets that were present near them but had difficulty grasping attention targets that were far away. This suggests that participants need to be trained repeatedly on distant objects of attention to be able to locate them instantaneously.
Chemistry in Retrieved Ryugu Asteroid Samples Revealed by Non-Invasive X-ray Microanalyses: Pink-Beam Fluorescence CT and Tender-Energy Absorption Spectroscopy
Authors: Northrup Paul , Tappero Ryan , Glotch Timothy D. , Flynn George J. , Yesiltas Mehmet , Kebukawa Yoko , Flores Leonard , Gemma Marina E. , Piccione Gavin
Published: April 2024

The Hayabusa2 space mission recently retrieved 5.4 g of material from asteroid Ryugu, providing the first direct access to pristine material from a carbonaceous asteroid. This study employs a novel combination of non-invasive synchrotron X-ray techniques to examine microscale chemistry (elemental distributions and element-specific chemical speciation and local structure) inside Ryugu grains without physically cutting the samples. Manganese primarily occurs in carbonate: Mn-bearing dolomite with minor earlier ankerite. Iron sulfides present as large single grains and as smaller particles in the finer-grained matrix are both predominantly pyrrhotite. At the 5 μm scale, Fe sulfides do not show the mineralogical heterogeneity seen in many carbonaceous meteorites but exhibit some heterogeneous localized oxidation. Iron is present often as intergrowths of oxide and sulfide, indicating incomplete replacement. Trace selenium substitutes for S in pyrrhotite. Copper is present as Fe-poor Cu sulfide. These results demonstrate multiple episodes of fluid alteration on the parent body, including partial oxidation, and help constrain the sequence or evolution of fluids and processes that resulted in the current grain-scale mineralogical composition of Ryugu materials.
Tourism Development through the Sense of UNESCO World Heritage: The Case of Hegra, Saudi Arabia
Authors: Sampieri Sara , Saoualih Abdellah , Safaa Larbi , de Carnero Calzada Fernando Martinez , Ramazzotti Marco , Martínez-Peláez Agustín
Published: April 2024

This study explores the perception of a “sense of place” among tourists visiting Hegra, an archaeological site in northern Saudi Arabia, through reviews on TripAdvisor. The 267 reviews on TripAdvisor between 2020 and 2023 were analyzed using the VADER sentiment polarity analysis tool and object modeling using the NMF machine learning algorithm. The results highlight positive factors linked to the history and uniqueness of the place while showing some critical issues related to isolation, cost, privatization, and competitiveness. The originality of the research lies in the type of case study chosen, an archaeological site of a country that has recently opened its doors to tourism, and in the pragmatic nature of the investigation, oriented towards the search for possible solutions to be adopted in terms of heritage management based on the feedback received for the development of the tourist destination.
Inclusion of Antifungal and Probiotic Lactiplantibacillus plantarum Strains in Edible Alginate Coating as a Promising Strategy to Produce Probiotic Table Grapes and Exploit Biocontrol Activity
Authors: De Simone Nicola , Scauro Angela , Fatchurrahman Danial , Russo Pasquale , Capozzi Vittorio , Spano Giuseppe , Fragasso Mariagiovanna
Published: April 2024

The use of lactic acid bacteria (LAB) for the probiotic enrichment of minimally processed fruit is a well-established practice in the literature. In addition, several LAB demonstrated a strain-specific ability to control harmful microorganisms and decay agents, improving shelf life, maintaining quality, and promoting the safety of fruits and vegetables. Edible coatings can help modulate the phenomena of gas exchange and water loss by fruits, representing protection from physical damage and spoilage phenomena linked to oxidation and the development of undesired microorganisms. At the same time, the coating can represent an innovative delivery matrix for the LAB strains of potential interest to improve safety and quality in the postharvest management of fruits. In this work, five Lactiplantibacillus plantarum strains, previously characterised for their probiotic and antifungal activity, were incorporated into a sodium alginate coating to develop edible probiotic coatings with antifungal properties for table grapes cv. Italia. The bacterial transfer and their survival were evaluated by comparing coated and uncoated table grapes during 14 days of cold storage at 4 °C. The alginate edible coating increased the number of viable cells transferred to the surface of the berries from about 5 to more than 7 Log CFU/g, with a crucial impact on the potential functional attributes of the final product. The ability of the functionalised coatings to counteract the decay development was evaluated on table grape berries artificially contaminated with Aspergillus niger CECT 2805. A significant reduction in lesion diameter was observed in the alginate coating with L. plantarum 11-A, with a reduction from 15.40 ± 1.14 mm of uncoated berries to 8.40 ± 1.14 mm of berries coated with L. plantarum 11-A. The lesion diameter reduction was also accompanied by a reduction in the symptoms of infection, such as browning around the wound. These results suggest the application of selected strains of L. plantarum as promising bio-resources to enhance the overall value of ready-to-eat fruits and vegetables, particularly in combination with edible coating as a carrier matrix. While a strain-dependent effect was not detected with respect to the improvement in the number of cells in the edible coating, a variability depending on the biotype used was detected for the properties linked to biocontrol, suggesting that the inclusion in edible packaging may represent an innovative criterion in the selection of lactobacilli to be applied postharvest.
Transcriptome and Pigment Analyses Provide Insights into Carotenoids and Flavonoids Biosynthesis in Camellia nitidissima Stamens
Authors: Feng Yi , Zhao Kunkun , Li Jiyuan , Wang Minyan , Yin Hengfu , Fan Zhengqi , Li Xinlei , Liu Weixin
Published: April 2024

Camellia nitidissima is famous for its golden flowers. Its flowers are rich in secondary metabolites, and they have ornamental, medicinal, and edible value. Pigment composition and regulation has been studied in the golden petals, but there has been little research on pigment composition or the molecular mechanism underlying yellow stamens in C. nitidissima. To explore the molecular mechanism of yellow stamen formation, three developmental stages (S0, S1, and S2) were used for transcriptome and pigment analyses. Pigment analysis showed that the flavonoid content increased sharply from the S0 to S1 stage and decreased from the S1 to S2 stage, and the carotenoid content increased sharply during yellow stamen formation (from the S1 to S2 stage). RNA-seq analysis showed that a total of 20,483 differentially expressed genes (DEGs) were identified. KEGG and heatmap analyses showed that flavonoid and carotenoid biosynthesis pathways were enriched, and we identified 14 structural genes involved in flavonoid biosynthesis and 13 genes involved in carotenoid biosynthesis and degradation. In addition, the expression of carotenoid- and flavonoid-related genes was consistent with carotenoid and flavonoid content. In addition, correlation network analysis indicated that the WARYK, MYB, bHLH, and AP2/ERF transcription factor families were screened for involvement in the biosynthesis of flavonoids and carotenoids. In this study, we describe the pathway associated with color formation in the stamens of C. nitidissima.
Hefting Heavy Shells: Sustenance Demands Caused by Various Abodes of the Hermit Crab Pagurus granosimanus
Authors: Torjman Brooke Z. , Iyengar Erika V.
Published: April 2024

Marine hermit crabs inhabiting different species of shells in the rocky intertidal may receive varied benefits and costs. Thick shell walls, sculpture, and certain silhouettes may increase protection against crushing predators and waves, but also the energy cost for bearing such a shell. To determine the relative energy demands on Pagurus granosimanus supporting one of three different species of shells commonly inhabited in nature, we measured the consumption of food by free-roaming, size-matched individuals after four days of food deprivation in the laboratory. Surprisingly, while all hermit crabs consumed a significant amount of food, that amount did not differ significantly across the types of shells inhabited, despite the significantly heavier weight of one type of shell (>150% of each of the other two species), and markedly different shell silhouettes. Whether our results were due to the inherent abilities of arthropods to support proportionally immense weights (physiology), reduced movements by animals in heavier shells (plastic behavior), or the way the hermit crabs bear the burden of the shell requires further investigation. Regardless, our results suggest that individuals of P. granosimanus that inhabit heavier shells that likely provide increased protection do not experience corresponding elevated food consumption requirements over the short term, even if those shells are not centered over the body mass of the hermit crab. Pagurus granosimanus crabs can bear the burden.
Groundwater Flow Model Calibration Using Variable Density Modeling for Coastal Aquifer Management
Authors: Perdikaki Martha , Chrysanthopoulos Efthymios , Markantonis Konstantinos , Kallioras Andreas
Published: April 2024

The paper investigates the mechanism of seawater intrusion and the performance of free and open-source codes for the simulation of variable density flow problems in coastal aquifers. For this purpose, the research focused on the Marathon Watershed, located in the northeastern tip of Attica, Greece. For the simulation of the groundwater system, MODFLOW, MT3DMS and SEAWAT codes were implemented, while sensitivity analysis and calibration processes were carried out with UCODE. Hydraulic head calibration was performed on the MODFLOW model, and TDS concentration was validated in the SEAWAT model. The calibrated parameters of the MODFLOW model were obtained for the variable density flow simulation with SEAWAT. The MODFLOW and SEAWAT hydraulic head outputs were analyzed and compared to one another. The outcome of this analysis is that SEAWAT produced slightly better results in terms of the hydraulic heads, concluding that parameter transferability can take place between the two models. For the purpose of the seawater intrusion assessment, the use of the SEAWAT code revealed that the aquifer is subjected to passive and passive–active seawater intrusion during wet and dry seasons, respectively. Finally, an irregular shape of a saltwater wedge is developed at a specific area associated with the hydraulic parameters of the aquifer.
Research on the Spatial Network Structure of Tourist Flows in Hangzhou Based on BERT-BiLSTM-CRF
Authors: Qi Danfeng , Wang Bingbing , Zhao Qiuhao , Jin Pingbin
Published: April 2024

Tourist flows, crucial information within online travelogues, reveal the interactive relationships between different tourist destinations and serve as the nerve center and link of the tourism system. This study takes Hangzhou, China, as a case to investigate the spatial network structure of its tourist flows. Firstly, a BERT-BiLSTM-CRF model and pan-attraction database are built to extract tourist attractions from online travelogues and create the tourist flow matrix. Then, this study uses social network analysis (SNA) to examine the structure of the tourist flow network from a county-level perspective. Additionally, GIS spatial analysis methods are applied to analyze the evolution of the tourist gravity center and standard deviation ellipse (SDE) of the network. The results reveal that the identification performances of the tourist flow extraction model this study proposed are significantly better than those of previous mainstream models, with an F1 value of 0.8752. Furthermore, the tourist flow network in Hangzhou displays a relatively sparse and unbalanced distribution, forming a “Core–Semi-Periphery–Periphery” structure. Lastly, from 2020 to 2022, the network’s gravity center experienced a shift towards the southwest, paralleled by an initial expansion and subsequent contraction of the SDE in the same southwest direction. These findings provide valuable insights into the spatial network structure of tourism in Hangzhou and can serve as a reference for policymakers to promote the “all-for-one” tourism.