bluuebunny/crossref_metadata_2025 huggingface dataset:
Steady- and Transient-State CFD Simulations of a Modified Barra–Costantini Solar System in Comparison with a Traditional Trombe–Michel Wall
Authors: Corasaniti Sandra , Manni Luca , Petracci Ivano , Potenza Michele
Published: January 2024

Passive solar systems are one of most important strategies to reduce the heating loads of buildings. The Trombe–Michel (TM) wall and its variants are some of the better-known structures in the field of solar systems. An alternative to the TM wall is the Barra–Costantini (BC) system. In the present paper, CFD numerical simulations, both in steady and transient states, of modified BC and TM walls were carried out in the winter season. Different interspace thicknesses were simulated in order to evaluate their effects on the temperature field and air velocity, and the numerical results were compared among them. It was found that the BC system offers greater hot air flow compared with the TM wall; the mass flow rate increased up to 43% in the BC system and up 28% in the TM system when the interlayer thickness was increased by 500%. The transient simulations (100 h simulated) demonstrated that the dynamic response of the BC wall was shorter than that of the TM wall, even when the TM wall was simulated with initial thermal conditions that were more advantageous than those for the BC wall. The BC system reached a periodic stabilized regime within 24 h, whereas the TM system failed to stabilize in 100 h. The results show that for both TM and BC structures, the interlayer thickness scarcely influenced the temperature of the environment reached (the temperature peak increased up to 3–4% as the interlayer thickness was increased by 500%), while larger air speed changes were observed in the BC system in the transient state compared with the TM system. Thus, in the TM system, the outlet air velocity was practically constant as the interlayer thickness was increased; in contrast, the outlet velocity peak increased up to 50% in the BC system. Moreover, the BC wall presented a quicker response to satisfy the ambient thermal loads.
Fault Detection and Prediction for Power Transformers Using Fuzzy Logic and Neural Networks
Authors: Mateus Balduíno César , Farinha José Torres , Mendes Mateus
Published: January 2024

Transformers are indispensable in the industry sector and society in general, as they play an important role in power distribution, allowing the delivery of electricity to different loads and locations. Because of their great importance, it is necessary that they have high reliability, so that their failure does not cause additional losses to the companies. Inside a transformer, the primary and secondary turns are insulated by oil. Analyzing oil samples, it is possible to diagnose the health status or type of fault in the transformer. This paper combines Fuzzy Logic and Neural Network techniques, with the main objective of detecting and if possible predicting failures, so that the maintenance technicians can make decisions and take action at the right time. The results showed an accuracy of up to 95% in detecting failures. This study also highlights the importance of predictive maintenance and provides a unique approach to support decision-making for maintenance technicians.
Exploring the Influence of Digital Transformation on Clean Energy Transition, Climate Change, and Economic Growth among Selected Oil-Export Countries through the Panel ARDL Approach
Authors: Sarabdeen Masahina , Elhaj Manal , Alofaysan Hind
Published: January 2024

Amid global imperatives to combat climate change and achieve sustainable economic development, the convergence of digital transformation and the transition to clean energy has emerged as a critical focal point for oil-exporting nations. This study comprehensively investigates the interplay of digital technology, clean energy transition, climate change, and economic growth among selected oil-exporting nations. Drawing upon a diverse set of economic and geographical contexts, this study uses panel data analysis of data from the World Bank’s Economic Indicators and the United Nations Development Program for the period from 2006 to 2020. The results show that digital technology reduces climate change by improving environmental quality, but internet and mobile access have insignificant and negative effects on environmental quality, respectively. Meanwhile, all technology variables negatively impact green energy and economic growth, while the Happy Planet Index and financial development positively impact the green energy transition. This study is important for regulators, producers, and consumers, as it provides a better understanding of the crucial role of digital transformation in sustainable development within oil-export countries. This study’s findings can be used to develop policy recommendations for a low-carbon economy, the promotion of digital transformation through green energy, and the management of climate change.
Breathing Planet Earth: Analysis of Keeling’s Data on CO2 and O2 with Respiratory Quotient (RQ), Part I: Global Respiratory Quotient (RQGlob) of Earth
Authors: Annamalai Kalyan
Published: January 2024

In biology, respiratory quotient (RQ) is defined as the ratio of CO2 moles produced per mole of oxygen consumed. Recently, Annamalai et al. applied the RQ concept to engineering literature to show that CO2 emission in Giga Tons per Exa J of energy = 0.1 ∗ RQ. Hence, the RQ is a measure of CO2 released per unit of energy released during combustion. Power plants on earth use a mix of fossil fuels (FF), and the RQ of the mix is estimated as 0.75. Keeling’s data on CO2 and O2 concentrations in the atmosphere (abbreviated as atm., 1991–2018) are used to determine the average RQGlob of earth as 0.47, indicating that 0.47 “net” moles of CO2 are added to which means that there is a net loss of 5.6 kg C(s) from earth per mole of O2 depleted in the absence of sequestration, or the mass loss rate of earth is estimated at 4.3 GT per year. Based on recent literature on the earth’s tilt and the amount of water pumped, it is speculated that there could be an additional tilt of 2.7 cm over the next 17 years. While RQ of FF, or biomass, is a property, RQGlob is not. It is shown that the lower the RQGlob, the higher the acidity of oceans, the lesser the CO2 addition to atm, and the lower the earth’s mass loss. Keeling’s saw-tooth pattern of O2 is predicted from known CO2 data and RQGlob. In Part II, the RQ concept is expanded to define energy-based RQGlob,En, and adopt the CO2 and O2 balance equations, which are then used in developing the explicit relations for CO2 distribution amongst atm., land, and ocean, and the RQ-based results are validated with results from more detailed literature models for the period 1991–2018.
Research on Multi-Objective Optimization of High-Speed Solenoid Valve Drive Strategies under the Synergistic Effect of Dynamic Response and Energy Loss
Authors: Yu Zhiqing , Yang Li , Zhao Jianhui , Grekhov Leonid
Published: January 2024

Under high-frequency operating conditions, the high-speed solenoid valve (HSV) experiences energy loss and heat generation, which significantly impacts its operational lifetime. Reducing the energy loss of an HSV without compromising its opening response characteristics poses a significant challenge. To address this issue, a finite element simulation model of an HSV coupled with a current feedback model is constructed to investigate the synergistic effects of dynamic response and energy loss. Prediction models for the opening response time, HSV driving energy, and Joule energy using a back propagation neural network (BPNN) are established. Furthermore, a multi-objective optimization study on the current driving strategy using a non-dominated sorting genetic algorithm II (NSGA-II) is conducted. After optimization, although there was a 6.24% increase in the opening response time, both HSV drive energy and Joule energy were significantly reduced by 15.67% and 22.49%, respectively. The proposed multi-objective optimization method for an HSV driving strategy holds great significance for improving its working durability.
Numerical Investigations of the Thermal-Hydraulic Characteristics of Microchannel Heat Sinks Inspired by Leaf Veins
Authors: Wang Jiale , Qi Shaohuan , Xu Yu
Published: January 2024

A microchannel heat sink (MCHS) is a potential solution for chip and battery thermal management. The new microchannel structure is beneficial for further improving the thermal-hydraulic performance of MCHSs. Inspired by leaf veins, six new channel structures were designed, and the effects of the channel structures (three parallel structures named PAR I, II, and III and three pinnate structures named PIN I, II, and III), channel depths (0.4, 0.8, and 1.6 mm), and heat fluxes (20, 50, and 80 kW/m2) were investigated via numerical simulation. The cooling medium was water, and the heating area was 40 × 40 mm2. Both PAR II and PIN III exhibit superior overall performance, characterized by the highest Nusselt number and the lowest heating wall temperature. Moreover, PIN III demonstrates the lowest standard deviation in heating wall temperature, while PAR II exhibits the lowest friction factor. The greater the channel depth is, the larger the solid–liquid contact area is, leading to a reduced wall temperature at the interface under identical conditions of inlet Reynolds number and heating wall heat flux. Consequently, an increase in the Nusselt number corresponds to an increase in the friction factor. The maximum value and standard deviation of the heating wall temperature increase with increasing heat flux, while the Nusselt number and friction factor remain unaffected. The overheating near the two right angles of the outlet should be carefully considered for an MCHS with a single inlet–outlet configuration.
Application of Wood and Vegetable Waste-Based Biochars in Sustainable Agriculture: Evaluation on Nitrate Leaching, Pesticide Fate, Soil Properties, and Brassica oleracea Growth
Authors: Losacco Daniela , Campanale Claudia , Triozzi Mariangela , Massarelli Carmine , Uricchio Vito Felice
Published: January 2024

Environmental pollution is caused by the unsustainable use of nitrogen (N) fertilizers and pesticides. Biochar (BC) is a carbon-based material applied to remove excess nutrients and pesticides from the environment. In pot experimental research, N fertilizer and pesticides alone and different biochar types were applied in the soil to evaluate cauliflower growth, soil quality, and leaching of agricultural contaminants. BC addition had increased nutrient availability based on feedstock origin. The surface structure results by SEM showed that the BC pore size was equal to 8.94 and 7.24 µm for mixed biochar and wood biochar, respectively. Nitrate concentrations in percolation water were 43.78 and 76.82 mg/L in mixed biochar and wood biochar, respectively. In soil treated with fertilizer and pesticides, NO3− was equal to 106.76 mg/L. Biochar’s binding with pesticides depends on its nature and structure. Adding wood biochar significantly reduced the leaching of fungicide compared to unamended soil, with a contraction of 327.86 and 3576 ng/L. Mixed biochar was more efficient for herbicide mitigation. FTIR was used to identify the functional groups on biochar-amended soil that play a role in the adsorption of agricultural compounds. Research shows that the BC application greatly affects the pesticide fate and N compounds of agricultural origin in soil.
Study on the Response of Vegetation Water Use Efficiency to Drought in the Manas River Basin, Xinjiang, China
Authors: Kong Jingjing , Zan Mei , Chen Zhizhong , Xue Cong , Yang Shunfa
Published: January 2024

Ecosystem water use efficiency (WUE) is an important measure of the degree of water–hydrogen coupling and an important indicator for assessing ecosystem responses to climate change. Drought adversely affects ecosystem security, particularly in irrigated agricultural areas; therefore, understanding the relationship between WUE and drought is important. This study revealed the spatial and temporal characteristics of drought in the Manas River Basin, Xinjiang, China, from 2001 to 2020 through multi-source data using standardised anomaly indices and mutation detection. It also quantitatively analysed the hysteresis effect and resilience characteristics of drought for different vegetation types in the study area. The results showed that droughts at a severe level occurred less frequently in most of the study area on average from 2001 to 2020, and that droughts in the vegetation growing season occurred more frequently, particularly in grasslands; the frequency of droughts in woodlands was low. Furthermore, the lag in WUE to drought occurred on a 3-month scale and accounted for 64.0% of the total watershed area. Finally, 38.16% of the regional vegetation ecosystems in the Manas River Basin exhibited drought resistance. In conclusion, our results provide novel insights into the water-use strategies of plants in the study area and will help facilitate WUE optimisation.
Identification of Cytospora Species Isolated from Branch Canker Diseases of Woody Plants in Tibet, China
Authors: Li Jie-Ting , Li Jiang-Rong , Jiang Ning
Published: January 2024

Branch canker diseases are important in forest ecosystems, causing economic and ecological losses. Members of Cytospora are common on cankered branches and associated with the diseases. Investigations on Cytospora cankers were conducted in Tibet, China, during 2022 and 2023. Samples were collected from Euonymus japonicus, Larix gmelinii, Malus pumila, M. spectabilis and Rosa omeiensis f. pteracantha, and cultures were obtained and identified by morphological features and molecular phylogeny of a combination of internal transcribed spacer region rDNA (ITS), the partial actin (act) region, RNA polymerase II second largest subunit (rpb2) gene, the translation elongation factor 1-alpha (tef1) gene and the partial beta-tubulin (tub2) gene. As a result, a new species is proposed herein named Cytospora lhasaensis and four known species are described for the first time from Tibet, viz. C. euonymina, C. gigaspora, C. mali and C. schulzeri. The current research enhances our understanding of the Cytospora species associated with woody host diseases in Tibet, China.
MangroveSeg: Deep-Supervision-Guided Feature Aggregation Network for Mangrove Detection and Segmentation in Satellite Images
Authors: Dong Heng , Gao Yifan , Chen Riqing , Wei Lifang
Published: January 2024

Mangrove forests are significant participants in coastal ecological environment systems. For the development of protection strategies, it is crucial to automatically and accurately detect the distribution and area of mangroves using satellite images. Although many deep-learning-based mangrove detection and segmentation algorithms have made notable progress, the complex regional structures and the great similarity between mangroves and the surrounding environment, as well as the diversity of mangroves, render the task still challenging. To cover these issues, we propose a novel deep-supervision-guided feature aggregation network for mangrove detection and segmentation called MangroveSeg, which is based on a U-shaped structure with ResNet, combining an attention mechanism and a multi-scale feature extraction framework. We also consider the detection and segmentation of mangroves as camouflage detection problems for the improvement and enhancement of accuracy. To determine more information from extracted feature maps in a hidden layer, a deep supervision model is introduced in up-sampling to enhance feature representation. The spatial attention mechanism with attention gates is utilized to highlight significant regions and suppress task-independent feature responses. The feature fusion module can obtain multi-scale information by binding each layer to the underlying information and update feature mappings. We validated our framework for mangrove detection and segmentation using a satellite image dataset, which includes 4000 images comprising 256 × 256 pixels; we used 3002 for training and 998 for testing. The satellite images dataset was obtained from the Dongzhaigang National Nature Reserve located in Haikou City, Hainan Province, China. The proposed method achieved a 89.58% overall accuracy, 89.02% precision, and 80.7% mIoU. We also used the trained MangroveSeg model to detect mangroves on satellite images from other regions. We evaluated the statistical square measure of some mangrove areas and found that the evaluation accuracy can reach 96% using MangroveSeg. The proposed MangroveSeg model can automatically and accurately detect the distribution and area of mangroves from satellite images, which provides a method for monitoring the ecological environment.
Carbon Allocation to Leaves and Its Controlling Factors and Impacts on Gross Primary Productivity in Forest Ecosystems of Northeast China
Authors: Li Zhiru , Lai Quan , Bao Yuhai , Sude Bilige , Bao Zhengyi , Liu Xinyi
Published: January 2024

Carbon allocation in forest ecosystems is essential for the optimization of growth. However, remote-sensing-based research on the estimation of carbon allocation in forests is inadequate. This article considers forests in northeastern China as the research area and uses leaf area index (LAI) data combined with random forest and structural equation modelling methods to study the spatiotemporal distribution characteristics and driving factors of carbon allocation to leaves (ΔLAI) in deciduous broad-leaved forests (DBF), deciduous coniferous forests (DNF), and mixed forests (MF) during the green-up period (GUP) at a monthly scale during April, May, June, and July from 2001 to 2021, and clarifies the impact of leaf carbon allocation on gross primary productivity (GPP). The ΔLAI was the highest in DBF in April and in DNF and MF in May. The ΔLAI in April with an increasing trend year by year in DBF and MF, and the ΔLAI in May with an increasing trend in DNF. Among all the direct and indirect relationships that affect ΔLAI, temperature (TEM) has the highest path coefficient for DBF’s ΔLAI in April (−1.213) and the start of the season (SOS) has the highest path coefficient for DNF (−1.186) and MF (0.815). ΔLAI in the GUP has a significant positive impact on the GPP. In the MF, the higher ΔLAI in May was most conducive to an increase in GPP. During the critical period, that is April and May, carbon allocation to leaves effectively improves the carbon sequestration capacity of forestland. This information is of great value for the development and validation of terrestrial ecosystem models.
Feeding Value Assessment of Five Varieties Whole-Plant Cassava in Tropical China
Authors: Li Mao , Zhou Hanlin , Zi Xuejuan , Lv Renlong , Tang Jun , Ou Wenjun , Chen Songbi
Published: January 2024

The feeding value of five varieties of whole-plant cassava (SC5, SC7, SC9, SC14, and SC205) was assessed through analysis of the nutritional composition and in situ ruminal degradability. The results showed abundant nutrients in whole-plant cassava, and the means of starch and crude protein (CP) were 267.7 and 176.8 (g kg−1), and ranged from 223.7 g kg−1 (SC9) to 296.4 g kg−1 (SC14) and from 142.4 g kg−1 (SC5) to 195.8 g kg−1 (SC9) (p < 0.05), respectively. Meanwhile, the moderate neutral detergent fiber (NDF) of whole-plant cassava was also observed and ranged from 266.2 g kg−1 in SC9 to 286.6 g kg−1 in SC14 (p < 0.05). In addition, the trace elements, such as Fe, Mn, Cu, and Zn, in whole-plant cassava were relatively enriched, and their mean concentrations were 135.8, 1225.2, 5.8, and 105.3 mg kg−1 (p < 0.05), respectively. Both the highest essential amino acid and total amino acid concentrations were obtained in SC7 (p < 0.01). The hydrogen cyanide (HCN) content of fresh and dried whole-plant cassava ranged from 76.5 to 131.6 and from 36.0 to 56.7 mg kg−1 (p < 0.05), respectively. The in situ dry matter ruminal degradability and metabolizable energy (ME) varied significantly (p < 0.05) and were consistently lowest and highest in SC9 and SC14, ranging from 50.9% to 80.0% and from 7.5 to 12.3 MJ kg−1, respectively. Collectively, all varieties of whole-plant cassava had a high feeding value, as reflected by abundant starch, minerals, amino acid, and water-soluble carbohydrates, while having a low fiber content and HCN toxicity, as well as excellent ruminal digestibility characteristics, and they could be used as a potential feed resource for ruminants.
Production with Fermentation Culture and Antioxidant Activity of Polysaccharides from Morchella esculenta
Authors: Li Xiaobei , Sun Qiuyan , Li Shuai , Chen Wenchao , Shi Zhimin , Xu Ziyin , Xu Lin , Chen Mei , Li Zhonghai
Published: January 2024

Morchella esculenta is a precious edible and medicinal fungus rich in protein, polysaccharides, polyphenols, amino acids, triterpenes, and other active components. In this study, MS-1 was isolated from the fruiting body of M. esculenta. Through conducting single-factor experiments and the response surface analysis of the culture conditions, the optimal culture components of an M. esculenta fermentation broth for extracellular polysaccharide production were determined, namely, 3.7% glucose, 2% yeast extract, and 0.15% sodium chloride. The polysaccharides MSF and MSL were extracted from the fruiting body of M. esculenta and the fermentation broth, respectively, and analyzed with gel permeation chromatography (GPC), monosaccharide composition, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and in vivo and in vitro antioxidant and anti-inflammatory activity analyses. The research results show that the calculated MW of MSF is 2.34 × 105 Da, and the calculated MW of MSL is 1.40 × 105 Da. MSF is composed of three monosaccharides: D-galactose, D-glucose, and D-mannose (molar ratio of 4.34:90.22:5.45). MSL consists of five monosaccharides: D-arabinose, D-galactose, D-glucose, D-mannose, and glucuronic acid (molar ratio of 0.31:14.71:13.03:71.43:0.53). The in vitro antioxidant test results show that MSF and MSL both have significant antioxidant activities. Activity experiments on MSF and MSL in zebrafish showed that MSF and MSL have significant repair effects on the oxidative damage caused by metronidazole in zebrafish embryos, and there were significant changes in the transcriptional activity levels of the oxidative stress-related genes SOD, Keap1, and Nrf2. Therefore, the polysaccharides MSF and MSL from MS-1 can be used as important raw materials for functional foods and drugs.
Dietary Nanometer Selenium Enhances the Selenium Accumulation, Nutrient Composition and Antioxidant Status of Paramisgurnus dabryanus spp.
Authors: Chen Jianhua , Xing Shaopeng , Xu Haixin , Zhu Honggeng , Fu Huiyun , Wang Haihua , Li Fugui , Zhu Ming
Published: January 2024

Selenium, an essential trace element, exerts beneficial effects on aquatic animals when present in suitable concentrations. This study investigates the effect of dietary nanometer selenium (Nano-Se) on the muscle selenium accumulation, nutrient composition, and antioxidant ability of Paramisgurnus dabryanus spp. Nano-Se was supplemented in the basal diets at levels of 0, 0.1, 0.2, 0.4, and 0.6 mg/kg. Three hundred fish, averaging 5.21 ± 0.06 g, were randomly divided into five groups and fed the experimental diet for 6 weeks. Fish with a dietary Nano-Se supplement of 0.2 mg/kg exhibited activities of SOD, GSH-Px, AKP, and CAT in the liver, which were significantly higher (p < 0.05) compared to the control diet, while MDA content was significantly lower (p < 0.05) in the 0.2 mg/kg group. The muscle selenium content significantly increased (p < 0.05) at ≥0.2 mg/kg Nano-Se levels. The highest levels of essential amino acids, EAA/TAA, and EAA/NEAA ratios were observed in fish fed 0.2 mg of Nano-Se. Thus, this study recommends incorporating 0.2 mg of Nano-Se per kg in the diet to enhance antioxidant defense, selenium content, and nutrient composition.
The Effect of Climate Change on Salmonid Fishes in Rivers
Authors: Jonsson Bror
Published: January 2024

Climate warming is a serious threat to many organisms, such as cold-adapted ectotherms [...]
From Navier to Stokes: Commemorating the Bicentenary of Navier’s Equation on the Lay of Fluid Motion
Authors: Tamburrino Aldo
Published: January 2024

The article presents a summarised history of the equations governing fluid motion, known as the Navier–Stokes equations. It starts with the work of Castelli, who established the continuity equation in 1628. The determination of fluid flow resistance was a topic that involved the brightest minds of the 17th and 18th centuries. Navier’s contribution consisted of the incorporation of molecular attraction effects into Euler’s equation, giving rise to an additional term associated with resistance. However, his analysis was not the only one. This continued until 1850, when Stokes firmly established the boundary conditions that must be applied to the differential equations of motion, specifically stating the non-slip condition of the fluid in contact with a solid surface. With this article, the author wants to commemorate the bicentennial of the publication of “Sur les Lois du Mouvement des Fluides” by Navier in the Mémoires de l’Académie Royale des Sciences de l’Institut de France.
Wind Velocity and Forced Heat Transfer Model for Photovoltaic Module
Authors: Hassanian Reza , Yeganeh Nashmin , Riedel Morris
Published: January 2024

This study proposes a computational model to define the wind velocity of the environment on the photovoltaic (PV) module via heat transfer concepts. The effect of the wind velocity and PV module is mostly considered a cooling effect. However, cooling and controlling the PV module temperature leads to the capability to optimize the PV module efficiency. The present study applied a nominal operating cell temperature (NOCT) condition of the PV module as a reference condition to determine the wind velocity and PV module temperature. The obtained model has been examined in contrast to the experimental heat transfer equation and outdoor PV module performance. The results display a remarkable matching of the model with experiments. The model’s novelty defines the PV module temperature in relation to the wind speed, PV module size, and various ambient temperatures that were not included in previous studies. The suggested model could be used in PV module test specification and provide analytical evaluation.
A Spectral/hp-Based Stabilized Solver with Emphasis on the Euler Equations
Authors: Ranjan Rakesh , Catabriga Lucia , Araya Guillermo
Published: January 2024

The solution of compressible flow equations is of interest with many aerospace engineering applications. Past literature has focused primarily on the solution of Computational Fluid Dynamics (CFD) problems with low-order finite element and finite volume methods. High-order methods are more the norm nowadays, in both a finite element and a finite volume setting. In this paper, inviscid compressible flow of an ideal gas is solved with high-order spectral/hp stabilized formulations using uniform high-order spectral element methods. The Euler equations are solved with high-order spectral element methods. Traditional definitions of stabilization parameters used in conjunction with traditional low-order bilinear Lagrange-based polynomials provide diffused results when applied to the high-order context. Thus, a revision of the definitions of the stabilization parameters was needed in a high-order spectral/hp framework. We introduce revised stabilization parameters, τsupg, with low-order finite element solutions. We also reexamine two standard definitions of the shock-capturing parameter, δ: the first is described with entropy variables, and the other is the YZβ parameter. We focus on applications with the above introduced stabilization parameters and analyze an array of problems in the high-speed flow regime. We demonstrate spectral convergence for the Kovasznay flow problem in both L1 and L2 norms. We numerically validate the revised definitions of the stabilization parameter with Sod’s shock and the oblique shock problems and compare the solutions with the exact solutions available in the literature. The high-order formulation is further extended to solve shock reflection and two-dimensional explosion problems. Following, we solve flow past a two-dimensional step at a Mach number of 3.0 and numerically validate the shock standoff distance with results obtained from NASA Overflow 2.2 code. Compressible flow computations with high-order spectral methods are found to perform satisfactorily for this supersonic inflow problem configuration. We extend the formulation to solve the implosion problem. Furthermore, we test the stabilization parameters on a complex flow configuration of AS-202 capsule analyzing the flight envelope. The proposed stabilization parameters have shown robustness, providing excellent results for both simple and complex geometries.
Quantitative Color Schlieren for an H2–O2 Exhaust Jet Developing in Air
Authors: Prisăcariu Emilia-Georgiana , Prisecaru Tudor
Published: January 2024

Throughout many decades, the Schlieren visualization method has been mainly used as means to visualize transparent flows in a qualitative manner. The images recorded provide data regarding the existence of the flow, or illustrate predicted flow geometries and details. The colored Schlieren method has been developed in the late 1890s and has always had the intent to provide quantitative data rather than qualitative pictures of the studied phenomena. This paper centers on applying a quantitative color Schlieren method to help determine the gasodynamic parameters of an H2–O2 exhaust jet, developing in air. A comparison between the parameters obtained through calibrating the color filter for the Schlieren method and the results from a CFD simulation is performed to assess the range of the CS (color Schlieren) measurement. This paper’s findings address the issues of calibrated color filter Schlieren encounter during its implementation and discusses possible errors appearing when the method is applied to a 3D flow. While the qualitative Schlieren images are still impressive to observe, the quantitative Schlieren presents challenges and a low measurement accuracy (75%) when applied to 3D flows and compared to 2D cases found in the literature (97–98%).
Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves
Authors: Ronca Carolina L. , Marques Sara S. , Ritieni Alberto , Giménez-Martínez Rafael , Barreiros Luisa , Segundo Marcela A.
Published: January 2024

Around two million tons of olive oil are produced in Europe annually, with Portugal being among the top five European olive oil-producing countries. Olive oil production results in a substantial amount of waste in the form of olive leaves. These discarded olive leaves contain valuable phenolic compounds with antioxidant, anti-inflammatory, hypoglycaemic, neuroprotective, and antiproliferative properties. Due to their richness in polyphenols with health-promoting properties, olive leaves can be considered a potential functional food ingredient. Thus, sustainable practices for reusing olive leaf waste are in demand. In this study, the polyphenolic content in olive leaves from different Portuguese locations was determined using HPLC-UV-Vis after defining the best fit-for-purpose liquid extraction strategy. The differences in the in vitro antioxidant activity in these samples were determined by several methodologies based on radical scavenging (against 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-2-picrylhydrazyl (DPPH), and peroxyl radical (ORAC)) and on reducing properties (cupric-reducing antioxidant capacity (CUPRAC), and Folin–Ciocalteu assay (FC)), to unveil the relationship between the profile and quantity of polyphenols with antioxidant mechanisms and their capacity. At last, the stability of extracted compounds upon lyophilization and exposition to surrogate biological fluids was assessed, envisioning the future incorporation of olive leaves extracted compounds in food products.
Effects of Different Heat Treatments on Yak Milk Proteins on Intestinal Microbiota and Metabolism
Authors: Shu Senbiao , Jing Rong , Li Liang , Wang Wenhan , Zhang Jinchao , Luo Zhang , Shan Yuanyuan , Liu Zhendong
Published: January 2024

Dairy products are susceptible to modifications in protein oxidation during heat processing, which can lead to changes in protein function, subsequently affecting intestinal health. Despite being a unique nutritional source, yak milk has not been thoroughly examined for the effects of its oxidized proteins on intestinal microbiota and metabolism. Hence, this study employed different heat treatment methods (low-temperature pasteurization, high-temperature pasteurization, and high-temperature sterilization) to induce oxidation in yak milk proteins. The study then assessed the degree of oxidation in these proteins and utilized mice as research subjects. Using metagenomics and metabolomics methods, this study examined the structure of intestinal microbial communities and metabolic products in mice consuming oxidized yak milk. The results showed a decrease in carbonyl and total thiol contents of yak milk proteins after different heat treatments, indicating that heat treatment causes oxidation in yak milk proteins. Metagenomic analysis of mouse intestinal microbiota revealed significant changes in 66 genera. In the high-temperature sterilization group (H), key differential genera included Verrucomicrobiales, Verrucomicrobiae, Akkermansiaceae, and 28 others. The high-temperature pasteurization group (M) mainly consisted of Latilactobacillus, Bacillus, and Romboutsia. The low-temperature pasteurization group (L) primarily comprised of Faecalibacterium, Chaetomium, Paenibacillaceae, Eggerthella, Sordariales, and 33 others. Functionally, compared to the control group (C), the H group upregulated translation and energy metabolism functions, the L group the M group significantly upregulated metabolism of other amino acids, translation, and cell replication and repair functions. Based on metabolomic analysis, differential changes in mouse metabolites could affect multiple metabolic pathways in the body. The most significantly affected metabolic pathways were phenylalanine metabolism, vitamin B6 metabolism, steroid hormone biosynthesis, and pantothenate and CoA biosynthesis. The changes were similar to the functional pathway analysis of mouse metagenomics, affecting amino acid and energy metabolism in mice. In summary, moderate oxidation of yak milk proteins exhibits a positive effect on mouse intestinal microbiota and metabolism. In conclusion, yak milk has a positive effect on mouse intestinal microflora and metabolism, and this study provides a scientific basis for optimizing dairy processing technology and further developing and applying yak milk.
Whole Flour of Purple Maize as a Functional Ingredient of Gluten-Free Bread: Effect of In Vitro Digestion on Starch and Bioaccessibility of Bioactive Compounds
Authors: Monsierra Luisina , Mansilla Pablo Sebastián , Pérez Gabriela Teresa
Published: January 2024

The growing demand for gluten-free products requires the study of alternatives to produce nutritionally and technologically favorable foods. The aim was to evaluate the content and antioxidant capacity of gluten-free bread enriched with whole flour of purple maize (PM) and how starch and bioaccessibility of antioxidant compounds were modified during in vitro digestion. Gluten-free bread was prepared with the addition of 34%, 50%, and 70% PM, and white maize bread served as control. The content of total polyphenols, anthocyanins, and antioxidant capacity through FRAP and TEAC was measured. Specific volume, crumb texture, and starch digestibility were determined in the breads. Simultaneously, in vitro digestion and dialysis by membrane were performed to evaluate the bioaccessible and potentially bioavailable fraction. Bread with 34% PM had a similar specific volume and crumb texture to the control, but higher content of polyphenols (52.91 mg AG/100 g), anthocyanins (23.13 mg c3-GE/100 g), and antioxidant capacity (3.55 and 5.12 µmol tr/g for FRAP and TEAC, respectively). The PM breads had a higher antioxidant content and capacity and higher slowly digestible and resistant starch than the control. These parameters increased as the PM proportion rose. After digestion, anthocyanins were degraded, polyphenols and antioxidant capacity decreased, but they remained potentially bioavailable, although to a lesser extent. Bread with 34% shows acceptable technological parameters, lower starch digestibility, and contribution of bioactive compounds with antioxidant capacity. This indicates that purple maize flour represents a potential ingredient to produce gluten-free bread with an improved nutritional profile.
A Polysaccharide from Ficus carica L. Exerts Immunomodulatory Activity in Both In Vitro and In Vivo Experimental Models
Authors: Ye Lin , Zhang Qin-Qiu , Lin Shang , Zhang Qing , Yan Jing , Wu Ding-Tao , Liu Shu-Xiang , Qin Wen
Published: January 2024

Polysaccharides from Ficus carica L. (FCP) exert multiple biological activities. As a biological macromolecule, the available knowledge about the specific structures and mechanisms of the biological activity of purified ‘Brunswick’ fig polysaccharides is currently limited. In the present study, chemical purification and characteristics were identified via chemical and instrumental analysis, and then the impact of FCP on immunomodulation activity in vitro and in vivo was examined. Structural characteristics showed that the molecular weight of the FCP sample was determined to be 127.5 kDa; the primary monosaccharides present in the FCP sample were galacturonic acid (GalA), arabinose (Ara), galactose (Gal), rhamnose (Rha), glucose (Glc), and xylose (Xyl) at a ratio of 0.321:0.287:0.269:0.091:0.013:0.011. Based on the investigation of in vitro immunomodulatory activity, FCP was found to stimulate the production of NO, TNF-α, and IL-6, and increased the pinocytic activity of macrophages. Further analysis revealed that FCP activated macrophages by interacting with Toll-like receptor 4 (TLR4). Moreover, the in vivo test results indicate that FCP showed a significant increase in serum pro-inflammatory factors in immunosuppressed mice. Overall, this study suggests that FCP has the potential to be utilized as a novel immunomodulator in the pharmaceutical and functional food industries.
Metabolomics of Red Wines Aged Traditionally, with Chips or Staves
Authors: Dumitriu (Gabur) Georgiana-Diana , Sánchez-Suárez Fernando , Peinado Rafael A. , Cotea Valeriu V. , de Lerma Nieves López , Gabur Iulian , Simioniuc Violeta
Published: January 2024

Traditionally and alternatively aged wines’ odour activity values (OAVs) are investigated to differentiate and highlight the differences between the selected methods. An analysis of the volatile aroma compounds of wines derived from ageing in barrels, oak chips, and staves was performed using stir bar sorptive extraction chromatography–mass spectroscopy (SBSE-GC-MS). The results showed that alcohols, esters, and oak compounds were the main contributors to aroma, and their OAVs were higher in the stave samples after 3 months than in the samples from the other two systems of ageing. Furthermore, wines aged with staves have stronger fruity, spiced, and woody aromas, while samples aged in barrels present more chemistry-driven, floral, caramelly, and creamy aromas. The staves—medium plus toast (SMPT at 3 months > 225) and chips—medium plus toast (CMPT at 3 months > 170) showed the highest levels of aromatic series, suggesting that alternative systems provided more powerful aromas than traditional systems, such as barrels—medium plus toast (BMPT at 3 months > 150). A principal component analysis (PCA), orthogonal partial least squares (OPLS) analysis, and cluster analysis allowed for a clear differentiation to be made between red wines according to ageing systems and ageing times. The odour activity values fingerprint in winemaking is a feasible approach to characterise and distinguish wines. Moreover, OAVs provide important information on the effects of production methods on wine quality and aroma profile.
Characteristics of Lactic Acid Bacteria as Potential Probiotic Starters and Their Effects on the Quality of Fermented Sausages
Authors: Liu Yinchu , Gao Sai , Cui Yue , Wang Lin , Duan Junya , Yang Xinyu , Liu Xiaochang , Zhang Songshan , Sun Baozhong , Yu Haojie , Gao Xiaoguang
Published: January 2024

The aim of this study was to explore the potential of commercial lactic acid bacteria (LAB) as probiotic starters in fermented sausages. We initially investigated the growth activity, acid production capability, and tolerance to fermentation conditions of Lactobacillus sakei, Lactiplantibacillus plantarum, and Pediococcus pentosaceus. All three LAB strains proved viable as starters for fermented sausages. Subsequently, we explored their potential as probiotics based on their antibacterial and antioxidant capabilities. L. plantarum exhibited stronger inhibition against Escherichia coli and Staphylococcus aureus. All three strains displayed antioxidant abilities, with cell-free supernatants showing a higher antioxidant activity compared to intact cells and cell-free extracts. Moreover, the activities of superoxide dismutase, glutathione peroxidase, and catalase were stronger in the cell-free supernatant, cell-free extract, and intact cell, respectively. Finally, we individually and collectively inoculated these three LAB strains into sausages to investigate their impact on quality during the fermentation process. External starters significantly reduced pH, thiobarbituric acid reactive substances, and sodium nitrite levels. The improvements in color and texture had positive effects, with the L. plantarum inoculation achieving higher sensory scores. Overall, all three LAB strains show promise as probiotic fermentation starters in sausage production.
Accurate Botanical Nomenclature: Pomegranate and the ‘Aril’ Misconception
Authors: Melgarejo Pablo , Martínez-Nicolás Juan José , Núñez-Gómez Dámaris , Almansa María Soledad , Legua Pilar
Published: January 2024

The pomegranate (Punica granatum L.) attracts attention in studies for its nutritional and medicinal properties. However, a recurring issue in the literature arises due to the multidisciplinary nature of these studies, leading to a mistaken repetition of basic botanical terms. The problem stems from the misapplication of the term “aril” to the pomegranate seed, despite the fruit being exariled, signifying the absence of an aril. This confusion may be attributed to the sarcotesta’s appearance, resembling a complete aril, coupled with a lack of awareness in fields such as medicine, pharmacy, and cosmetics. This study specifically examines the Kingdom-variety pomegranate, due its economic importance in the fruit market. The fruits were evaluated at different developmental stages—initial, intermediate, and commercial. Magnification photography techniques were used to study the development state of the pomegranate fruits. The physiological studies confirm that the pomegranate seed constitutes the complete grain, with the juicy, sweet part surrounding it identified as the testa, not an aril. The findings underscore a persistent error in the existing literature, emphasizing the necessity for dissemination and education in future studies. A thorough grasp of pomegranate anatomy and precise use of terminology are indispensable for ensuring accuracy and rigor in scientific communication.
The Mitochondrial Genomes of Siboglinum plumosum and Oligobrachia dogieli (Annelida: Siboglinidae) and Their Phylogenetic Analysis
Authors: Skalon Elizaveta K. , Starunova Zinaida I. , Petrov Sergey A. , Smirnov Roman V. , Zaitseva Olga V. , Starunov Viktor V.
Published: January 2024

Frenulates are a group of sedentary Annelida within the family Siboglinidae that inhabit the ocean floor and present a unique challenge for comprehensive molecular and phylogenetic investigations. In this study, we focused on the frenulates, specifically assembling the mitochondrial genomes of Siboglinum plumosum and Oligobrachia dogieli. The phylogenetic reconstruction placed S. plumosum as a sister taxon to S. ekmani, and O. dogieli as a sister taxon to S. fiordicum, supporting the non-monophyletic nature of the genus Siboglinum. Overall, this study supports the phylogeny of the family Siboglinidae while highlighting the need for additional molecular data within frenulates.
Selection and Verification of Standardized Reference Genes of Angelica dahurica under Various Abiotic Stresses by Real-Time Quantitative PCR
Authors: Zhang Jing , He Xinyi , Zhou Jun , Dong Zhuang , Yu Han , Tang Qi , Yuan Lei , Peng Siqing , Zhong Xiaohong , He Yuedong
Published: January 2024

In traditional Chinese medicine, Angelica dahurica is a valuable herb with numerous therapeutic applications for a range of ailments. There have not yet been any articles on the methodical assessment and choice of the best reference genes for A. dahurica gene expression studies. Real-time quantitative PCR (RT-qPCR) is widely employed as the predominant method for investigating gene expression. In order to ensure the precise determination of target gene expression outcomes in RT-qPCR analysis, it is imperative to employ stable reference genes. In this study, a total of 11 candidate reference genes including SAND family protein (SAND), polypyrimidine tract-binding protein (PTBP), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin (ACT), TIP41-like protein (TIP41), cyclophilin 2 (CYP2), elongation factor 1 α (EF1α), ubiquitin-protein ligase 9 (UBC9), tubulin β-6 (TUB6), thioredoxin-like protein YLS8 (YLS8), and tubulin-α (TUBA) were selected from the transcriptome of A. dahurica. Subsequently, three statistical algorithms (geNorm, NormFinder, and BestKeeper) were employed to assess the stability of their expression patterns across seven distinct stimulus treatments. The outcomes obtained from these analyses were subsequently amalgamated into a comprehensive ranking using RefFinder. Additionally, one target gene, phenylalanine ammonia-lyase (PAL), was used to confirm the effectiveness of the selected reference genes. According to the findings of this study, the two most stable reference genes for normalizing the expression of genes in A. dahurica are TIP41 and UBC9. Overall, our research has determined the appropriate reference genes for RT-qPCR in A. dahurica and provides a crucial foundation for gene screening and identifying genes associated with the biosynthesis of active ingredients in A. dahurica.