bluuebunny/crossref_metadata_2025 huggingface dataset:
Learners’ Perspectives on ARCH + STEM: Integration of Archaeology and Indigenous Knowledges with Western Knowledges of STEM
Authors: Simpson Amber , McCann Jada , Miroff Laurie
Published: April 2023

It is often the case that the integration of archaeology and Indigenous knowledges with science, technology, engineering, and mathematics (STEM) concepts, practices, and processes is missing in school-based contexts, which limits learners’ perspectives of STEM. This study examined how an afterschool program focused on the intersection of STEM and the field of archaeology and Indigenous knowledges developed and/or enhanced middle school learners’ perspective of (a) Indigenous people; (b) the field of archaeology; and (c) STEM concepts, practices, and processes. Data were collected through 15 focus group interviews held approximately six weeks after the program’s conclusion. The results demonstrated that learners gained a new perspective of STEM, integrating Indigenous and Western perspectives; gained an understanding of archaeology and archaeological concepts; and made connections between STEM concepts embedded in the program and those within and outside of their school experience. Based on the results, we contend that the integration of alternative knowledges and ways of being and seeing the world within nonformal learning environments has the potential to diminish differences and/or tensions between Indigenous and Western knowledges and perspectives of STEM, as well as support archaeology as an approach to facilitating the learning and application of STEM concepts, practices, and processes.
Investigation of Current Collapse Mechanism on AlGaN/GaN Power Diodes
Authors: Doublet Martin , Defrance Nicolas , Okada Etienne , Pace Loris , Duquesne Thierry , Emilien Bouyssou , Yvon Arnaud , Idir Nadir , De Jaeger Jean-Claude
Published: April 2023

In this paper, a methodology is proposed for studying the current collapse effects of Gallium Nitride (GaN) power diodes and the consequences on the dynamic on-resistance (RON). Indeed, the growing interest of GaN based, high frequency power conversion requires an accurate characterization and a deep understanding of the device’s behaviour before any development of power converters. This study can ultimately be used to model observed trap effects and, thus, improve the equivalent electrical model. Using an in-house circuit and a specific experimental setup, a current-collapse phenomenon inherent to gallium nitride semiconductor is studied on planar 650 V—6 A GaN diodes by applying high voltage stresses over a wide range of temperatures. With this method, useful data on activation energy and capture cross section of electrical defects linked to dynamic RON are extracted. Finally, the origins of such defects are discussed and attributed to carbon-related defects.
Reinforcement Learning Based Dual-UAV Trajectory Optimization for Secure Communication
Authors: Qian Zhouyi , Deng Zhixiang , Cai Changchun , Li Haochen
Published: April 2023

Unmanned aerial vehicles (UAV) can serve as aerial base stations for users due to their flexibility, low cost, and other characteristics. However, due to the high flight position of UAVs, the air-to-ground (ATG) channels usually dominate with line-of-sight (LoS), which can be easily eavesdropped by multiple eavesdroppers. This poses a challenge to secure communication between UAVs and ground users. In this paper, we study a UAV-aided secure communication in an urban scenario where a legitimate UAV Alice transmits confidential information to a legitimate user Bob on the ground in the presence of several eavesdroppers around it and a UAV Jammer sends artificial noise to interfere with the eavesdroppers. We aim to maximize the physical layer secrecy rates in the system by jointly optimizing the trajectories of UAVs and their transmitting power. Considering the time-varying characteristics of channels, this problem is modeled as a Markov decision process (MDP). An improved algorithm based on double-DQN is proposed in the paper to solve this MDP problem. Simulation results show that the proposed algorithm can converge quickly under different environments, and the UAV transmitter and UAV jammers can find the optimal location correctly to maximize the information secrecy rate. It also shows that the double-DQN (DDQN) based algorithm works better than the Q-learning and deep Q-learning network (DQN).
Analysis of Frequency Regulation Capability and Fatigue Loads of Wind Turbine Based on Over-Speed Control
Authors: Wang Yingwei , Guo Yufeng , Chen Yuheng , Xu Weimao
Published: April 2023

This study primarily analyzes the frequency regulation capability and fatigue loads of wind turbines based on over-speed control. Initially, a small-signal model of the wind turbine is established, which describes the output characteristics of the wind turbine under different control modes and wind speeds. Next, the model is used to analyze the wind turbine’s frequency regulation capability and to calculate the optimal frequency regulation parameter range based on the phase margin. Finally, a combination of frequency domain and time domain analysis is used to examine the influence of over-speed control on the fatigue loads of low-speed shafts, towers, and blades, which determines the wind speed range suitable for frequency regulation. The Fast (Fatigue, Aerodynamics, Structures, and Turbulence) Code V8 is used to simulate the dynamic characteristics of the wind turbine.
Comparative Study of Magnet Temperature Estimation at Low Speeds Based on High-Frequency Resistance and Inductance
Authors: Kim Hwigon , Kang Seon-Gu , Jung Jae-Jung , Jung Hyun-Sam
Published: April 2023

Interior permanent magnet synchronous motors have been widely used in electric vehicles. These motors employ Nd-Fe-B as the permanent magnet, which is vulnerable to temperature variations. Moreover, some features of Nd-Fe-B magnets are related to temperature, which can affect motor characteristics. Therefore, magnet temperature is an important parameter and methods for estimating it have been developed. In particular, a signal injection method has been developed for low-speed regions. In this method, two parameters are employed: high-frequency resistance and high-frequency inductance. In this paper, these two methods are compared to determine which parameter is more appropriate for estimations at low speeds and to reveal whether signal injection methods can be applied to the standstill condition. The comparison indicated that the high-frequency inductance-based method has a stronger correlation with the magnet temperature at low speed and standstill conditions than the high-frequency resistance-based method.
Application of Enterprise Architecture and Artificial Neural Networks to Optimize the Production Process
Authors: Juzoń Zbigniew , Wikarek Jarosław , Sitek Paweł
Published: April 2023

Production optimization is a complex process because it must take into account various resources of the company and its environment. In this process, it is necessary to consider the enterprise as a whole, taking into account the interaction between its key elements, both in the technological and business layer. For this reason, the article proposes the use of enterprise architecture, which facilitates the interaction of these layers in the production optimization process. As a result, a proprietary meta-model of enterprise architecture was presented, which, based on good practices and the assumptions of enterprise architecture, facilitates the construction of detailed optimization models in the area of planning, scheduling, resource allocation, and routing. The production optimization model formulated as a mathematical programming problem is also presented. The model was built taking into account the meta-model. Due to the computational complexity of the optimization model, a method using an artificial neural network (ANN) was proposed to estimate the potential result based on the structure of the model and a given data instance before the start of optimization. The practical application of the presented approach has been shown based on the example of optimization of the production of an exemplary production cell where the cost of storage and the number of unfulfilled orders and maintenance are optimized.
Using High-Level Representation Difference Constraint and Relative Reconstruction Constraint for Defending against Adversarial Attacks
Authors: Gao Song , Wang Xiaoxuan , Dong Yunyun , Yao Shaowen
Published: April 2023

Adversarial examples in which imperceptible perturbations to the input can easily subvert a well-trained model’s prediction pose huge potential security threats to deep neural networks (DNNs). As an effective way to resist adversarial samples, input reconstruction can eliminate the antagonism of adversarial examples in the inference process without involving modifications to the target model’s structure and parameters. However, preprocessing inputs often results in some loss of the protected model’s prediction accuracy. In this paper, we introduce a new input reconstruction method that adopts the high-level representation difference constraint and the relative reconstruction constraint on a dual autoencoder to advance the prediction accuracy of the protected model. The high-level representation difference constraint utilizes the gap between the protected model’s high-level representations, activated by clean images, and their adversarial examples to guide the training of the dual autoencoder. Additionally, the relative reconstruction constraint is imposed on latent representations and their noisy versions to advance the robustness of the dual autoencoder to tiny perturbations. The extensive empirical experiments on two real datasets, CIFAR-10 and ImageNet, show that the presented approach demonstrates exceptional performance in resisting different types of attacks.
Analysis of the Terminal Response Characteristics of the Twisted Three-Wire Cable Excited by a Plane Wave Field
Authors: Nie Yaning , Chen Yazhou , Zhou Xing , Zhao Min , Wang Yan
Published: April 2023

A twisted three-wire cable model with uniform twisting characteristics is proposed in this paper, and its terminal response under external electromagnetic wave irradiation is calculated using the TLM method based on Taylor model. The triple-stranded triple-helix structure is determined in the method and the parametric equations of the twisted wire bundle in the Cartesian coordinate system are provided. Then, the frequency domain equations for the voltage and current of the twisted three-wire cable under field-to-wire coupling are derived and extended to apply to scenarios with arbitrary polarization and irradiation in the incident direction based on the transmission-line theory. Finally, the response laws of the twisted three-wire wire with different cable lengths, termination loads, and pitches coupling under external electromagnetic wave irradiation are studied. A uniform twisted three-wire cable can suppress the increased induced current on the cable. In addition, the excellent characteristics of the twisted three-wire cable in terms of immunity to electromagnetic interference are also verified by comparing the frequency domain response with that of a parallel three-wire cable.
Exploring the Validity of Plane and Spherical Millimeter-Wave Incidences for Multiple-Diffraction Calculations in Wireless Communication Systems
Authors: López-Segovia Alba , Rodríguez-Rodríguez Ignacio , Rodríguez José-Víctor , Juan-Llácer Leandro , Campo-Valera María , Woo Wai Lok
Published: April 2023

The focus of this work is to determine at which threshold can the results for both plane and spherical wave incidence assumptions either converge or deviate when performing multiple diffraction attenuation calculations. The analysis has been carried out—for various millimeter-wave frequencies, inter-obstacle spacings, and angles of incidence—by employing a pair of two-dimensional (2D) hybrid formulations based on both the uniform theory of diffraction and physical optics (UTD-PO). This way, we seek to demonstrate under which circumstances each wave incidence assumption can be valid in environments that entail millimeter-wave bands. Based on this, we may ensure the minimum necessary distance from the transmitter to the first diffracting obstacle for the convergence of the spherical wave incidence solution onto that of the plane wave with a relative error below 0.1%. Our results demonstrate that for less than four diffracting elements, the minimum necessary distance engages in quasi-linear behavior under variations in both the angle of incidence and obstacle spacing. Notably, the considered frequencies (60–100 GHz) have almost no bearing on the results. Our findings will facilitate the simplified, more accurate and realistic planning of millimeter-wave radio communication systems, with multiple diffractions across various obstacles.
Connectivity Analysis with Co-Channel Interference for Urban Vehicular Ad Hoc Networks
Authors: Ren Shihai , Zhao Junhui , Zhang Huan , Li Xuan
Published: April 2023

In urban vehicular ad hoc networks (VANETs), the complex channel environment and co-channel interference resulted in the uncertain delay of inter-vehicle packet transmission, which causes serious delay jitter. Connectivity is proposed as a key metric to describe this uncertainty. However, existing works lack a discussion of inter-vehicle connectivity in urban VANETs, particularly with regards to the process of transmitting packets between vehicles. In this paper, we analyze the connectivity probability of urban VANETs under co-channel interference with both complete and incomplete information. When the information is complete, we model the time-varying nature of co-channel interference and channel fading as delay jitter and analyze inter-vehicle connectivity in a time-varying environment. Then, when complete information is unavailable, we estimate the probability distribution of co-channel interference by combining the distribution of multiple parameters with the free space propagation model (Friss) model and Nakagami-m fading model. The expression for the connectivity performance of vehicle-to-vehicle (V2V) links is derived from the signal interference plus noise ratio (SINR) of the destination V2V link. Finally, we analyze the implications of various factors on connectivity, such as the transmit power of the signal, the arrival rate of packets, the number of channels and vehicles, and the distance between the transmitting vehicle and the receiving vehicle. The numerical analysis shows that co-channel interference and signal fading significantly affect inter-vehicle connectivity.
Study of Twisted Tape Inserts Segmental Application in Low-Concentrated Solar Parabolic Trough Collectors
Authors: Stanek Bartosz , Ochmann Jakub , Węcel Daniel , Bartela Łukasz
Published: April 2023

This article presents the results of an analysis of heat enhancement intensification using twisted tapes in linear absorbers for low-concentration parabolic trough collectors, a technology frequently considered as a supplementary energy source for industrial heat production. This contribution proposes a segmented application of different twisted tapes to intensify heat absorption. A 33.7 mm tubular absorber placed in the collector focal point with an aperture of 1.8 m was selected. The temperature range of the heat transfer fluid was chosen at 60–250 °C. The impact of inserts with twisted ratios of 1, 2 and 4 on system operation was analysed using the Ansys Fluent and mathematical model. The models used were validated based on experimental results from a parabolic trough collector with solar simulator test bench. The results indicated that for the range of mass flow between 0.15–0.3 kg/s, the most optimal is applying twisted ratio 1, except for the highest-temperature section. In this section, it is more optimal to use an insert with a twisted ratio 2, due to the lower need for pumping and the higher efficiency increment. The long-term analysis for the case study plant indicated that the proposed approach increased power gain by 0.27%.
The Hybridization of PSO for the Optimal Coordination of Directional Overcurrent Protection Relays of the IEEE Bus System
Authors: Wang Yuheng , Habib Kashif , Wadood Abdul , Khan Shahbaz
Published: April 2023

The hybridization of PSO for the Optimal Coordination of Directional Overcurrent Protection Relays (DOPR) of the IEEE bus system proposes a new method for coordinating directional overcurrent protection relays in power systems. The method combines the hybrid particle swarm optimization (HPSO) algorithm and a heuristic PSO algorithm to find the minimum total operating time of the directional overcurrent protection relays with speed and accuracy. The proposed method is tested on the IEEE 4-bus, 6-bus, and 8-bus systems, and the results are compared with those obtained using traditional coordination methods. The collected findings suggest that the proposed method may produce better coordination and faster operation of DOPRs than the previous methods, with an increase of up to 74.9% above the traditional technique. The hybridization of the PSO algorithm and heuristic PSO algorithm offers a promising approach to optimize power system protection.
Battery Dynamic Balancing Method Based on Calculation of Cell Voltage Reference Value
Authors: Vikhorev Nikolay , Kurkin Andrey , Aleshin Dmitriy , Ulyanov Danil , Konstantinov Maksim , Shalukho Andrey
Published: April 2023

The article is devoted to solving the problem of charge equalization of multi-element batteries with rated voltage up to 1000 V, operating in dynamic modes with different charge and discharge depths. This article proposes a method of balancing the voltages of power battery elements. The essence of the proposed method is to form a reference signal equivalent to the reference voltage of the battery element for the current state of charge. The novelty of the method presented in this article, in comparison with relevant existing techniques, lies in active control over the balancing circuit proportional to real cell voltage deviation from the reference value. The proposed method can be used both for passive balancing techniques based on ballast resistors, and for circuits made on electromagnetic energy redistribution systems between galvanic cells. A number of Simulink models were developed to determine the electrical parameters of active and passive balancing circuits. Performance and accuracy study of balancing a multi-element battery in charge and discharge modes was conducted by Simulink models. It was established that, compared to classical methods, the proposed balancing method enhances the accuracy by 1.43 times and improves dynamic indices of the balancing process at any state of charge of batteries. The proposed balancing method is a perspective for energy storage systems based on multi-element batteries for power supply nodes of high-power loads with pulsed and repeated short-term operation modes.
Prediction of Betavoltaic Battery Parameters
Authors: Yakimov Eugene B.
Published: April 2023

The approaches for predicting output parameters of betavoltaic batteries are reviewed. The need to develop a strategy for predicting these parameters with sufficient accuracy for the optimization of betavoltaic cell design without using the simple trial and error approach is discussed. The strengths and weaknesses of previously proposed approaches for the prediction are considered. Possible reasons for the difference between the calculated and measured parameters are analyzed. The depth dependencies of beta particles deposited energy for Si, SiC, GaN, and Ga2O3 and 20% purity 63Ni and titanium tritide as radioisotope sources are simulated using the Monte Carlo algorithm taking into account the full beta energy spectrum, the isotropic angular distribution of emitted electrons and the self-absorption inside the radioisotope source for homogeneously distributed emitting points. The maximum short circuit current densities for the same semiconductors and radioisotope sources are calculated. The methodology allowing the prediction of betavoltaic cell output parameters with accuracy no worse than 30% is described. The results of experimental and theoretical investigations of the temperature dependence of betavoltaic cell output parameters are briefly discussed. The radiation damage by electrons with the subthreshold energy and the need to develop models for its prediction is considered.
Environmental Impacts and Benefits of Tofu Production from Organic and Conventional Soybean Cropping: Improvement Potential from Renewable Energy Use and Circular Economy Patterns
Authors: Colimoro Martina , Ripa Maddalena , Santagata Remo , Ulgiati Sergio
Published: April 2023

This study aimed to quantify and evaluate the main environmental impacts generated in each phase of tofu production as well as its main co-products (soy milk, food integrators, etc.) and by-products (straw, hulls, etc.) from organic and conventional soybean cropping and to compare them with the impacts of conventional protein sources (e.g., livestock meat and snails). The starting case study was the tofu production company “Tigusto SA” located in Cugnasco-Locarno (Switzerland). The analysis was performed by means of the life cycle assessment (LCA) method, applying a systematic cradle-to-gate approach, from cultivation and extraction of raw materials to the final products. The aim of the analysis was to identify the phases that cause the main environmental burdens and to propose alternative solutions to minimize the impacts. Results show the importance of applying circularity-based scenarios, such as reuse/recycling of residues and the use of renewable energy, which could increase the sustainability of the investigated system, providing environmental and economic benefits.
Contribution to Knowledge of the Oriental Taxa of the Diduga (Lepidoptera: Erebidae: Arctiinae)
Authors: Bayarsaikhan Ulziijargal , Heppner John B. , Bucsek Karol , Cha Yeong-Bin , Bae Yang-Seop , Kwon Hyung Wook
Published: April 2023

The type material of Diduga costata Moore, [1887], D. flavicostata (Snellen, 1879), D. fulvicosta Hampson, 1891, D. barlowi Holloway, 2001, and D. zetes Bucsek, 2014 are presented. Three new species are described based on the genitalia of type specimens from Indonesia (Sulawesi) and Laos. Three new combinations and one new synonym are established. An updated checklist of known species of the genus are presented with information of depositors and distributions. Illustrations of the adults and genitalia of the type materials and examined species are provided.
Sustainability Assessment for the Protected Area Tourism System from the Perspective of Ecological-Economic-Social Coordinated Development
Authors: Zhang Xiangju , Zhong Linsheng , Yu Hu , Wang Ling-En
Published: April 2023

Tourism is a significant way for the public to enjoy the cultural ecosystem services provided by protected areas (PAs). However, with PAs being expected to make much wider ecological, social and economic contributions to sustainability and human well-being, PA managers face challenges in coordinating tourism with other goals, such as ecological conservation and local community development. To address this challenge, we developed a sustainability assessment framework that considers the PA, local community, and tourism as a complex system comprising social, economic, and ecological subsystems from the perspective of subsystem relationships. The coupling coordination degree model and the obstacle degree model were applied to assess sustainability of the tourism system in Qinghai Lake Nature Reserve of China. The assessment results indicate that the sustainability index fluctuated between 2010 and 2019, but generally exhibited an upward trend, undergoing three stages and reaching the stage in 2019 where ecological sustainability took the lead. At this stage, the coupling coordination degree between the economy and society subsystems was at its lowest, and the economic subsystem faced the highest obstacle degree. The study demonstrates that involving scholars and administrators in the index selection process and considering both index information and management concerns when determining index weight makes the coupling coordination degree model more suitable for PA tourism systems. The assessment method developed in this study effectively reflects the temporal evolution of PA tourism system sustainability and provides valuable implications for coordinated ecological-economic-social management by analyzing obstacle factors.
Effect of Cork Flour Supplementation on the Growth Indices and Rhizosphere Bacterial Communities of Quercus variabilis Seedlings
Authors: Che Yuying , Kong Yong , Song Shangwen , Yi Xianfeng , Zhou Jing , Liu Baoxuan
Published: April 2023

Substrate and rhizosphere microorganisms are key factors affecting seedling growth; however, the effects of seedling substrates and rhizosphere bacteria on the growth of Quercus variabilis are not completely understood. Here, Q. variabilis seedlings were grown in substrates with and without cork flour, as follows: H substrate (charcoal soil/cork flour/perlite, 1:1:2), S substrate (cork flour/perlite, 1:1), and the control (CK) substrate (charcoal soil/perlite, 3:2). High-throughput sequencing and qPCR were used to investigate the effects of these substrates on seedling growth, physiological indices, and rhizosphere bacterial communities. Root and shoot weights of seedlings grown in H and S substrates were significantly higher than those of seedlings grown in CK. Moreover, H was conducive to chlorophyll synthesis in seedling leaves, and the transpiration rate and intercellular CO2 concentration of the leaves of seedlings grown in H were higher than those of seedlings grown in CK. The number of rhizosphere bacterial 16S rRNA copies was significantly greater in the case of seedlings grown in S than for those grown in H and CK. As well, rhizosphere bacterial richness was higher in seedlings grown in H and S than in those grown in CK. Thus, cork-flour-supplemented substrates are beneficial for seedling growth and development, seedling rhizosphere bacterial abundance and diversity, and the abundance of nitrogen and phosphorus metabolism-promoting microbial taxa.
The Effect of Storage Conditions on the Strength Characteristic of Glulam Beams
Authors: Mirski Radosław , Kuliński Marcin , Kawalerczyk Jakub , Walkiewicz Joanna , Czarnecki Rafał
Published: April 2023

Despite many outdoors applications, the number of works aimed to determine the effect of changing conditions on the properties of glulam beams, in particular those produced in non-standard arrangements, is few. Therefore, the aim of this study was to assess changes in flexural strength properties (MOE, MOR) of the beams stored for 30 months in varying conditions. Analyzed variants of pine GLT beams included five-meter-long structural elements reinforced with oak timber, high-quality pine timber and steel rods stored both in the roofed shed outdoors and inside the climatic chamber. Moisture content of the beam varied significantly depending on the placement of the sensors (on the surface or inside the beam). The average modulus of elasticity after 30 months of storage decreased by approx. 7% compared to initial values. The results varied depending on both the assumed beam arrangement and the applied conditions.
A Comparison between the Latest Models of Li-Ion Batteries and Petrol Chainsaws Assessing Noise and Vibration Exposure in Cross-Cutting
Authors: Neri Francesco , Laschi Andrea , Bertuzzi Lucia , Galipò Giovanni , Frassinelli Niccolò , Fabiano Fabio , Marchi Enrico , Foderi Cristiano , Marra Elena
Published: April 2023

Chainsaw operators are exposed to many hazards that can lead to health problems. The two most frequently documented ergonomics threats in the use of chainsaws are noise and vibration exposure. Since the use of battery chainsaws is increasing due to the growing improvements in battery life and power, the study aims to compare the difference in terms of noise emission and vibration levels of the following two new models of chainsaws: the battery-powered Stihl MSA 300 and the petrol-powered Stihl MS 261 C-M. Black pine and European beech logs were cross-cut in order to evaluate both noise and vibration exposure. The results show that the use of battery-powered chainsaws, in comparison to the petrol one, can reduce the daily vibration exposure by more than 51% and the noise dose by 11%. The daily vibration exposure of 1.60 ms−2 and 1.67 ms−2 measured for the battery-powered chainsaw on Black pine and on European beech, respectively, is far from the daily exposure action value set by the EU directives for health and safety requirements (2.5 ms−2). On the contrary, the daily noise exposure for the battery chainsaw was 93 dB(A), exceeding the upper exposure action value of 85 dB(A).
Field Drying for Enhancing Biomass Quality of Eucalyptus Logs and Trees in Florida, USA
Authors: Rockwood Donald L. , Tamang Bijay , Ellis Martin F.
Published: April 2023

Field drying Eucalyptus biomass can minimize the storage requirements, transportation costs, and/or the cost associated with biomass drying for biochar and other products. In central Florida, 12 6-year-old and 12 8-year-old Eucalyptus amplifolia and Eucalyptus grandis trees were field dried over two seasons, with two months of field drying in each season, and two tree forms (logs, whole tree). The whole tree average initial moisture content (MCod) on a dry basis ranged between 115 and 121% in E. amplifolia and 116 and 119% in E. grandis. The season and duration of field drying affected drying, but species, tree size, and tree form did not. In southern Florida, 19 3+-year-old coppice stems of an E. grandis × Eucalyptus urophylla hybrid clone (EH1) were field dried over two months of one season, with and without tree tops. The whole tree initial MCod ranged between 119 and 138%. The duration of field drying affected drying, but tree size and tree tops did not. Both studies suggest that field drying can effectively reduce wood MC and thus enhance E. amplifolia, E. grandis, and EH1 biomass quality.
In Vitro Rumen Fermentation Kinetics Determination and Nutritional Evaluation of Several Non-Conventional Plants with Potential for Ruminant Feeding
Authors: Maduro Dias Cristiana S. A. M. , Nunes Helder , Vouzela Carlos , Madruga João , Borba Alfredo
Published: April 2023

Using invasive plants as non-conventional forage in livestock production can contribute to meeting climate change targets and provide a competitive advantage in a global market. This study evaluated the nutritional potential of several non-conventional plants: Pennisetum setaceum, Ricinus communis, Arundo donax, Acacia melanoxylon, Opuntia ficus-indica, Agave americana, Pittosporum undulatum, and Hedychium gardnerianum. Chemical composition, in vitro digestibility, gas production, and energy estimates were determined. Opuntia showed the lowest DM value (6.65%), while the highest was found for Acacia (39.43%). Ricinus recorded the highest levels of CP (23.56% DM), RFV (273.86), and in vitro gas production at 24 h (43.49 mL/200 mg DM). The highest NDF (80.39% DM), HEM (39.03% DM), and CEL (36.81% DM) values were observed for Pennisetum. Agave produced the highest amount of gas from the start to the end of incubation (22.68 to 48.99 mL/200 mg DM), while Acacia produced the least (3.83 to 14.78 mL/200 mg DM). The highest ME (8.72 MJ/kg DM) and NEL (5.06 MJ/kg DM) estimates were obtained for Agave. Correlations between the chemical compositions and feed quality indices of the plants were observed, showing strong negative correlations between ADF and DMD, OMD, and DMI (r > 0.86, p < 0.01). We can conclude that all these non-conventional plants have potential as an alternative feed for ruminants when there are fodder shortages.
Influence of the Physical Properties of Samples in the Use of NIRS to Predict the Chemical Composition and Gas Production Kinetic Parameters of Corn and Grass Silages
Authors: Dias Cristiana S. A. M. Maduro , Nunes Helder P. B. , Borba Alfredo E. S.
Published: April 2023

Livestock production is the main economic engine of the Azores. Given the role nutrition plays in animal performance and the context of limited Averages sharing the same letter are noagricultural area of the archipelago, optimising the quality and availability of the fodder used in feeds takes on an important role in increasing the competitiveness and viability of the industry. This work evaluated the potential of NIR spectroscopy to quantify several chemical and biological parameters used to assess silage quality in the specific agroclimatic context of the Azores. Reference values were determined for 400 grass silage and 400 corn silage samples. The corresponding NIR spectra were extracted, and mathematical models capable of correlating these readings with the various parameters were built. The best results were obtained for crude protein, neutral detergent fibre, acid detergent fibre, and crude ash for both fresh and dry samples. For the biological parameters concerning gas production, no satisfactory results were reached. It was concluded that it was feasible to build models capable of accurately predicting these important quality parameters, which demonstrates that NIRS is a viable technique that can be used in the Azores to perform a close and timely monitoring of forage quality and to facilitate the management and optimisation of diets.
Effect of Lactic Acid Bacteria Fermentation on the Polar Compounds Content with Antioxidant and Antidiabetic Activity of Avocado Seed Extracts
Authors: Razola-Díaz María del Carmen , De Montijo-Prieto Soumi , Aznar-Ramos María José , Jiménez-Valera María , Ruiz-Bravo Alfonso , Verardo Vito , Gómez-Caravaca Ana María
Published: April 2023

Avocado seeds, a common waste in the avocado processing industry, have been found to have several bioactivities, such as anticancer, antimicrobial, hypocholesterolemic, antioxidant, and antidiabetic activities, among others. Nowadays, this wastage is causing an environmental problem, so the use of new technologies to take advantage of it is a novel field of research. In this study, the submerged fermentation by lactic acid bacteria was used as a novel tool for improving the bioactive compound extraction from avocado seeds. Avocado seeds were fermented by different strains, their polar compounds were identified and quantified by HPLC-ESI-TOF-MS, the antioxidant activity was measured by DPPH and FRAP assays, and the antidiabetic activity was analyzed by the alpha-amylase assay. A total of 32 polar compounds were identified, with 13 of them being described in avocado seeds for the first time. Avocado seeds fermented by Pentosaceus acidilactici showed the highest sum of polar compounds (6279.63 ± 67.74 µg/g d.w.), and by extension, of hydroxytyrosol glucoside (2989.76 ± 3.64 µg/g d.w.). Lactiplantibacillus plantarum CECT 9567 showed the highest antioxidant activity measured by both DPPH and FRAP assays (6294.67 ± 19.44 and 6846.91 ± 2.13 µg TE/g d.w., respectively). Furthermore, Lactiplantibacillus plantarum CECT 748T had the highest antidiabetic activity (52.15% ± 0.67% inhibition of alpha-amylase activity), attributable to the polyphenols. According to the results, submerged fermentation by lactic acid bacteria led to an interesting increase of the polar compounds’ extractability of avocado seeds, consequently improving the bioactivities of the extracts, which could then be used for food nutraceutical or cosmetic purposes.
Extending Learning and Collaboration in Quantum Information with Internet Support: A Future Perspective on Research Education beyond Boundaries, Limitations, and Frontiers
Authors: Delgado Francisco
Published: April 2023

Quantum information is an emerging scientific and technological discipline attracting a growing number of professionals from various related fields. Although it can potentially serve as a valuable source of skilled labor, the Internet provides a way to disseminate information about education, opportunities, and collaboration. In this work, we analyzed, through a blended approach, the sustained effort over 12 years to involve science and engineering students in research education and collaboration, emphasizing the role played by the Internet. Three main spaces have been promoted, workshops, research stays, and a minor, all successfully developed through distance education in 2021–2022, involving students from various locations in Mexico and the United States. The success of these efforts was measured by research-oriented indicators, the number of participants, and their surveyed opinions. The decisive inclusion of the Internet to facilitate the blended approach has accelerated the boost in human resources and research production. During the COVID-19 pandemic, the Internet played a crucial role in the digital transformation of this research education initiative, leading to effective educative and collaborative experiences in the “New Normal”.
Shear Strength Prediction of Steel-Fiber-Reinforced Concrete Beams Using the M5P Model
Authors: Al-Abdaly Nadia Moneem , Hussein Mahdi J. , Imran Hamza , Henedy Sadiq N. , Bernardo Luís Filipe Almeida , Al-Khafaji Zainab
Published: April 2023

This article presents a mathematical model developed using the M5P tree to predict the shear strength of steel-fiber-reinforced concrete (SFRC) for slender beams using soft computing techniques. This method is becoming increasingly popular for addressing complex technical problems. Other approaches, such as semi-empirical equations, can show known inaccuracies, and some soft computing methods may not produce predictive equations. The model was trained and tested using 332 samples from an experimental database found in the previous literature, and it takes into account independent variables such as the effective depth d, beam width bw, longitudinal reinforcement ratio ρ, concrete compressive strength fc, shear span to effective depth ratio a/d, and steel fiber factor Fsf. The predictive performance of the proposed M5P-based model was also compared with the one of existing models proposed in the previous literature. The evaluation revealed that the M5P-based model provided a more consistent and accurate prediction of the actual strength compared to the existing models, achieving an R2 value of 0.969 and an RMSE value of 37.307 for the testing dataset. It was found to be a reliable and also straightforward model. The proposed model is likely to be highly helpful in assessing the shear capacity of SFRC beams during the pre-planning and pre-design stages and could also be useful to help for future revisions of design standards.
Anthocyanins and Vascular Health: A Matter of Metabolites
Authors: Festa Joseph , Hussain Aamir , Al-Hareth Zakia , Singh Harprit , Da Boit Mariasole
Published: April 2023

Anthocyanins are a subgroup of flavonoid polyphenols previously investigated for improving cardiovascular health and preventing the development of endothelial dysfunction. However, their poor bioavailability raises the question of whether the observed biological activity is due to their metabolites. Phenolic metabolites can reach higher plasma concentrations and can persist in the circulation for periods much longer than their original anthocyanin form; therefore, the biological activity and health promoting effects of anthocyanins may differ from their metabolites. To address this, recent studies have facilitated different cell models, in vivo studies and explored physiologically relevant concentrations to better understand their mechanisms of action. The criteria were chosen based on previous reports demonstrating that anthocyanins can improve endothelial function via modulation of the Akt-endothelial nitric oxide synthase pathway and transcription factors Nrf2 and NF-κB, which made it critical to assess the phenolic metabolites’ modes of action via these pathways. This review demonstrates how phenolic metabolites differ in bioactivity from their precursor anthocyanin, demonstrating improved endothelial function in response to inflammatory mediators at concentrations that are tolerated in vivo. The review highlights the crucial need for further studies to focus on improving the bioavailability of metabolites in isolation and explore the effect of metabolites in mixtures.
Physico-Chemical Property, Sensory Profile and Consumer Acceptability of Water Buffalo (Bubalus bubalis L.) Chocolate Milk Using Alkalized and Natural Cocoa Powder
Authors: Juvinal Joel , De Steur Hans , Schouteten Joachim , Muhammad Dimas , De Leon Alma , Dewettinck Koen , Gellynck Xavier
Published: April 2023

Due to its nutritional quality and palatability, chocolate milk beverages are gaining popularity globally. Alkalized cocoa powder is mostly used in its production since it provides for more intense color and dispersibility, but it has a negative effect on the phytochemical content of cocoa powder. Studies have suggested that water buffalo milk is superior to other milk due to its higher protein content and superior emulsion properties. As such, this study investigated the physico-chemical characteristics, sensory profile, and consumer acceptability of commercial and prototype water buffalo chocolate milk incorporated with alkalized and natural cocoa powder. Based on four buffalo chocolate milk samples, consumer acceptance was assessed by 120 consumers, which was combined with descriptive sensory data using a trained panel (n = 8) to determine drivers of liking. Compositional proximate analysis of alkalized and natural cocoa powders showed a significant difference in pH, moisture content, ash content, and fat content. Descriptive analysis showed that 8 out of 13 attributes (color, visual sandiness, cocoa and vanilla aroma, smoothness, creaminess, vanilla taste, and chocolate aftertaste) were effective discriminators of sensory attributes. Overall, buffalo chocolate milk samples were equally liked, but hedonic ratings of the individual attributes revealed that the samples were statistically different for color, viscosity (mouthfeel), and chocolate flavor. Partial least square regression (PLSR) identified chocolate flavor, viscous appearance, viscous mouthfeel, and bitter aftertaste as positive “drivers of liking”. The darker color provided by alkalized cocoa powder did not increase consumer liking. The purchase intention was equal for all chocolate milk samples, whether alkalized or natural. Both cocoa powders showed comparable performance in the manufacture of buffalo chocolate milk. Using natural cocoa powder may be beneficial to local producers of cocoa powder and cocoa farmers since it is easier to produce, while it can provide a marketing advantage for dairy beverages in the global trend of going back to “organic” and “natural”.
Choline and Fish Oil Can Improve Memory of Mice through Increasing Brain DHA Level
Authors: Li Jin , Jian Yaqiong , Liu Ruonan , Zhao Xianfeng , Mao Jiangyi , Wei Wei , Jiang Chenyu , Zhang Lina , Wang Yi , Zhou Peng
Published: April 2023

Docosahexaenoic acid (DHA) is highly enriched in the brain, and is essential for normal brain development and function. However, evidence suggests that currently used supplements, such as fish oil, do not significantly increase brain DHA levels. Therefore, this study aimed to investigate whether combined fish oil and choline supplementation could affect the type and enrich the content of DHA in the brain. The results revealed that the combined intake of fish oil and choline upregulated the expression of key transporters and receptors, including MFSD2A, FATP1, and FABP5, which increased the uptake of DHA in the brain. Additionally, this supplementation improved the synthesis and release of acetylcholine in the brain, which, in turn, enhanced the learning and memory abilities of mice. These findings suggest that the combined intake of fish oil and choline improves the bioavailability of DHA in the brain.
Fish Freshness Indicator for Sensing Fish Quality during Storage
Authors: Kim Do-Yeong , Park Sung-Woo , Shin Han-Seung
Published: April 2023

This study aims to develop a freshness indicator for fish products that changes color to indicate ammonia among volatile base compounds (TVB-N) generated during storage. Through an optimization experiment, we observed the indicator’s color change relative to the ammonia concentration standard, finally selecting cresol red and bromocresol purple for the indicator mixture. In addition, eco-DEHCH and Breathron film were applied to the freshness indicator, considering environmental and economic values. For the storage experiment, Chub mackerel (Scomber japonicus), Spanish mackerel (Scomberomorus niphonius), and Largehead hairtail (Trichiurus lepturus) samples were stored at three different temperatures (4, 10, and 20 °C) for seven days, and we measured pH, TVB-N, total bacterial count, and ammonia content every 24 h. The pH-sensitive sensors’ color changes monitor amine release, especially ammonia, from decomposing fish. The chromatic parameter ∆E value increased significantly with fish product storage periods. We confirmed that when the freshness limit and bacterial spoilage level were reached, the color of the indicator changed from yellow to black and sequentially changed to purple as the storage period increased. Therefore, a developed freshness indicator can be used for determining the quality of fish products quickly and non-destructively by reflecting the freshness and spoilage degree of fish products during storage.
Participation of FaTRAB1 Transcription Factor in the Regulation of FaMADS1 Involved in ABA-Dependent Ripening of Strawberry Fruit
Authors: Lu Wenjing , Wei Xiaopeng , Han Xueyuan , Chen Renchi , Xiao Chaogeng , Zheng Xiaojie , Mao Linchun
Published: April 2023

Abscisic acid (ABA) plays a crucial role in regulating the ripening of non-climacteric strawberry fruit. In the present study, ABA was confirmed to promote strawberry ripening and induce the down-regulation of FaMADS1. The transient silence of FaMADS1 in strawberries promoted fruit ripening and induced the content of anthocyanin and soluble pectin but reduced firmness and protopectin through a tobacco rattle virus-induced gene silencing technique. In parallel with the accelerated ripening, the genes were significantly induced in the transiently modified fruit, including anthocyanin-related PAL6, C4H, 4CL, DFR, and UFGT, softening-related PL and XTH, and aroma-related QR and AAT2. In addition, the interaction between FaMADS1 and ABA-related transcription factors was researched. Yeast one-hybrid analysis indicated that the FaMADS1 promoter could interact with FaABI5-5, FaTRAB1, and FaABI5. Furthermore, dual-luciferase assay suggested that FaTRAB1 could actively bind with the FaMADS1 promoter, resulting in the decreased expression of FaMADS1. In brief, these results suggest that the ABA-dependent ripening of strawberry fruit was probably inhibited through inhibiting FaMADS1 expression by the active binding of transcript FaTRAB1 with the FaMADS1 promoter.
Antibacterial Activity and Mechanism of Peptide PV-Q5 against Vibrio parahaemolyticus and Escherichia coli, Derived from Salt-Fermented Penaeus vannamei
Authors: Dai Jingyi , Jin Ritian , Gao Jialong , Aweya Jude Juventus , Lin Rong , Li Guiling , Yang Shen
Published: April 2023

The increasing threat posed by antibiotic-resistant pathogens has prompted a shift to the use of naturally-derived antimicrobial peptides (AMPs) in place of chemical preservatives in controlling foodborne pathogens. In this study, ten peptides were identified from salt-fermented shrimps (Penaeus vannamei) using ultra-performance liquid chromatography-mass spectrometry. One of the peptides, designated PV-Q5 (QVRNFPRGSAASPSALASPR), with most features of an AMP, was further explored and found to possess strong antibacterial activity against Vibrio parahaemolyticus and Escherichia coli, with a minimum inhibitory concentration of 31.25 μg/mL. Moreover, PV-Q5 increased bacterial cell membrane permeability and ruptured bacteria cell membranes, as revealed by transmission electron microscopy. Circular dichroism analysis showed that the conformation of PV-Q5 was a random coil in phosphate-buffered saline and α-helical in sodium dodecyl sulfate, which is conducive for interaction with bacteria cell membranes. These findings indicated that PV-Q5 could find potential use in food preservation to control foodborne pathogenic bacteria.