bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the Association between Nutrient Intake and Food Insecurity among Children and Adolescents in Palestine Using Machine Learning Techniques
Authors: Qasrawi Radwan , Sgahir Sabri , Nemer Maysaa , Halaikah Mousa , Badrasawi Manal , Amro Malak , Vicuna Polo Stephanny , Abu Al-Halawa Diala , Mujahed Doa’a , Nasreddine Lara , Elmadfa Ibrahim , Atari Siham , Al-Jawaldeh Ayoub
Published: May 2024

Food insecurity is a public health concern that affects children worldwide, yet it represents a particular burden for low- and middle-income countries. This study aims to utilize machine learning to identify the associations between food insecurity and nutrient intake among children aged 5 to 18 years. The study’s sample encompassed 1040 participants selected from a 2022 food insecurity household conducted in the West Bank, Palestine. The results indicated that food insecurity was significantly associated with dietary nutrient intake and sociodemographic factors, such as age, gender, income, and location. Indeed, 18.2% of the children were found to be food-insecure. A significant correlation was evidenced between inadequate consumption of various nutrients below the recommended dietary allowance and food insecurity. Specifically, insufficient protein, vitamin C, fiber, vitamin B12, vitamin B5, vitamin A, vitamin B1, manganese, and copper intake were found to have the highest rates of food insecurity. In addition, children residing in refugee camps experienced significantly higher rates of food insecurity. The findings emphasize the multilayered nature of food insecurity and its impact on children, emphasizing the need for personalized interventions addressing nutrient deficiencies and socioeconomic factors to improve children’s health and well-being.
Machine Learning for Predicting Key Factors to Identify Misinformation in Football Transfer News
Authors: Runsewe Ife , Latifi Majid , Ahsan Mominul , Haider Julfikar
Published: May 2024

The spread of misinformation in football transfer news has become a growing concern. To address this challenge, this study introduces a novel approach by employing ensemble learning techniques to identify key factors for predicting such misinformation. The performance of three ensemble learning models, namely Random Forest, AdaBoost, and XGBoost, was analyzed on a dataset of transfer rumours. Natural language processing (NLP) techniques were employed to extract structured data from the text, and the veracity of each rumor was verified using factual transfer data. The study also investigated the relationships between specific features and rumor veracity. Key predictive features such as a player’s market value, age, and timing of the transfer window were identified. The Random Forest model outperformed the other two models, achieving a cross-validated accuracy of 95.54%. The top features identified by the model were a player’s market value, time to the start/end of the transfer window, and age. The study revealed weak negative relationships between a player’s age, time to the start/end of the transfer window, and rumor veracity, suggesting that for older players and times further from the transfer window, rumors are slightly less likely to be true. In contrast, a player’s market value did not have a statistically significant relationship with rumor veracity. This study contributes to the existing knowledge of misinformation detection and ensemble learning techniques. Despite some limitations, this study has significant implications for media agencies, football clubs, and fans. By discerning the credibility of transfer news, stakeholders can make informed decisions, reduce the spread of misinformation, and foster a more transparent transfer market.
Shape Dependence of Photoresponsive Molecular Crystals Composed of Naphthyl Acrylic Acid Stimulated by Solid-State [2 + 2] Photocycloaddition
Authors: Li Tian-Yuan , Du Yu-Ze , Xu Tian-Yi , Zhang Tian-Le , Tong Fei
Published: May 2024

Photomechanical molecular crystals, actuated by solid-state photochemical reactions, manifest a spectrum of mechanical motions upon light exposure, underscoring their prospective integration into the next generation of intelligent materials and devices. Utilizing the solid-state photodimerization of naphthyl acrylic acid as a paradigm, this study delved into the interplay between crystal morphology and reaction dynamics on the photomechanical responses of molecular crystals. Distinct crystal forms—bulk, microrods, and microplates—were cultivated through tailored crystallization conditions. While bulk crystals of naphthyl acrylic acid (NA) underwent shattering and splintering upon UV light exposure, the microplate counterparts displayed unique cracking patterns with fissures yet retained their overall structural integrity. In contrast, NA microrods underwent pronounced bending under identical irradiation conditions. These phenomena are attributed to the efficient lattice reconfiguration stemming from the [2 + 2] cycloaddition photochemical reaction within the crystals. An intermediate fluorescence enhancement was observed across all crystal types upon light exposure. Collectively, our results underscore the pivotal role of crystal shape in dictating photomechanical behavior, thereby heralding novel strategies for developing advanced photomechanical materials.
Assessing the Utility of Acoustic Radiation Force Impulse in the Evaluation of Non-Alcoholic Fatty Liver Disease with Severe Obesity or Steatosis
Authors: Kang Yeo Wool , Baek Yang Hyun , Lee Jong Hoon , Roh Young Hoon , Kwon Hee Jin , Moon Sang Yi , Son Min Kook , Jeong Jin Sook
Published: May 2024

Background: Non-alcoholic fatty liver disease (NAFLD) encompasses a heterogeneous spectrum ranging from simple steatosis to fibrosis and cirrhosis. Fibrosis, associated with long-term overall mortality and liver-related events, requires evaluation. Traditionally, liver biopsy has been the gold standard for diagnosing fibrosis. However, its invasive nature, potential complications, and sampling variability limit widespread use. Consequently, various non-invasive tests have been developed as alternatives for diagnosing fibrosis in NAFLD patients. Aim: This study aimed to compare the accuracy of non-invasive tests (NITs) and evaluate the diagnostic accuracy of acoustic radiation force impulse (ARFI), one of the point shear wave techniques, compared to conventional methods, assessing its effective role in diagnosis. Methods: This is a retrospective study; a total of 136 patients diagnosed with fatty liver disease through ultrasonography were enrolled. The anthropometric data of the patients were collected on the day of admission and blood tests, measurements of ARFI, and a point shear test were conducted using abdominal ultrasound; a biopsy was performed the following day. In addition, we calculated the aspartate aminotransferase-to-platelet ratio index (APRI) index based on four factors (FIB-4) and the NAFLD fibrosis score (NFS). Subsequently, we assessed the diagnostic accuracy of NITs within various subgroups based on the extent of obesity, steatosis, or NAFLD activity score. Results: ARFI has been shown to have the highest diagnostic value among various NITs, with AUROC values of 0.832, 0.794, 0.767, and 0.696 for ARFI, APRI, FIB-4, and NFS, respectively. In the morbidly obese subgroup, the AUROC values of ARFI, APRI, FIB-4, and NFS were 0.805, 0.769, 0.736, and 0.674. In the group with severe steatosis or non-alcoholic steatohepatitis (NASH), the AUROC values were 0.679, 0.596, 0.661, and 0.612, respectively, for severe steatosis and 0.789, 0.696, 0.751, and 0.691, respectively, for NASH. Conclusions: In conclusion, ARFI is not affected by various factors and maintains diagnostic accuracy compared to serum NITs. Therefore, we can recommend ARFI as a valuable diagnostic test to screen for advanced fibrosis in patients with NAFLD.
Assistive Technology for Higher Education Students with Disabilities: A Qualitative Research
Authors: Papadopoulos Konstantinos , Koustriava Eleni , Isaraj Lisander , Chronopoulou Elena , Manganello Flavio , Molina-Carmona Rafael
Published: May 2024

The objective of this qualitative investigation is to identify the assistive technology recognized by students with disabilities and to determine the assistive technology (software apps and devices) they require both at university and at home. A total of forty-two students, comprising 20 males and 22 females, were recruited from four different countries (Germany, Greece, Italy, and Spain) for participation in this study. The sample encompassed 10 students with visual impairments, 11 with hearing impairments, 11 with mobility impairments, and 10 with specific learning disabilities. Semi-structured interviews were conducted with the students either online or in person. Content analysis was employed to scrutinize the data obtained from these interviews. The outcomes of this analysis shed light on the assistive technology acknowledged, utilized, or desired by students with disabilities in both academic and domestic settings. The findings from this study carry practical implications for fostering inclusive and accessible education within higher education institutions, benefiting accessibility units/offices staff as well as teaching personnel.
Enactment of Transformational School Leadership—Insights from Primary School and System Leaders
Authors: Wilson Heenan Inez , Lafferty Niamh , McNamara Patricia Mannix
Published: May 2024

Transformational leadership has been proposed as an approach that can inspire effective change. How this is manifest in schools is understudied in Irish primary schools, which have undergone significant change in recent years. The focus of this qualitative research study was primary school and system leaders’ knowledge of transformational school leadership, perceived benefits, limitations, and feasibility, and how transformational school leadership actually manifests in practice. Participants were recruited using purposive sampling. In-depth interviews were carried out with principals, deputy and assistant principals, and former school inspectors, with the interviews aligned to the following research questions: (1) How can we characterize school and system leaders’ knowledge, understanding and perceptions regarding the feasibility of transformational school leadership? (2) How do transformational school leadership behaviours manifest in primary school settings? Data analysis yielded the following themes and sub-themes: (1) Understanding of transformational school leadership: (i) transformation, change and growth, (ii) relationships, (iii) vision, mission, and goals, (iv) leading; (2) Perceptions of feasibility of transformational school leadership: (i) realism, (ii) people and relationships, (iii) practical challenges; (3) Benefits of transformational school leadership: (i) aspiration, (ii) culture, (iii) motivation and modelling, (iv) school community, (v) delivering quality learning; (4) Limitations of transformational school leadership: (i) personality, (ii) pressure, (iii) slow process, (iv) unexpected variables; (5) Manifestations of transformational school leadership: (i) idealised influence, (ii) inspirational motivation, (iii) individualised consideration, (iv) intellectual stimulation, (v) school development, (vi) improving curricular offerings. Participants’ positive disposition to transformational school leadership was encouraging and suggests the need for further research, specifically to examine potential synergy between transformational and distributed school leadership.
Linking School Culture to Successful Curriculum Reform
Authors: Grgić Marina , Jutzi Michelle
Published: May 2024

This study focused on the connection between organisational school culture and the success of curriculum reform. Utilizing a sample of 348 teachers in 25 Swiss schools, we investigated how different school culture types correlate with teachers’ perceived success of the current process of implementing the “Media and Information Literacy” curriculum. We found that the school culture type Clan is the most dominant across the schools and found a negative connection between the school culture type Hierarchy and teachers’ perceived reform success. An exploratory cluster analysis was used to identify further profiles of school culture that were not based on the dominant culture but were determined based on the distribution of mean values. Two other profiles were identified in a further procedure: Collegial Associates and Competitive Organisations. These results thus fill a gap in the previous research on school culture that had particularly set out to identify the dominant school culture. Based on the results, we cannot only confirm the validity of the Organisational Culture Assessment Instrument for Swiss schools but also give indications as to which characteristics of school culture types are hindering the perceived success of curriculum reforms from the teachers’ points of view.
Is Consuming Avocados Equally Sustainable Worldwide? An Activity to Promote Eco-Social Education from Science Education
Authors: Guevara-Herrero Irene
Published: May 2024

The socio-environmental crisis in which we find ourselves makes it necessary to promote a citizenship capable of facing global challenges in an informed, critical, and participatory manner. Given the shortcomings of environmental education practices and the limitations of teachers to develop effective activities in their classrooms, it is necessary to review and redefine teacher training. In accordance with the case study research method, we present the results of the implementation of an activity for teacher training on environmental socio-scientific issues: the production and consumption of avocados in Spain. The aim is to find out how students use the evidence and what perspectives they integrate when making argued decisions, which will allow us to assess the didactic potential of the designed activity and contribute to the consolidation of the didactic dimension of eco-social education. The results show the students’ ability to use the evidence in a critical and reflective way, sometimes oriented toward the search for and proposal of solutions, and also their ability to address the problem using a systemic approach, integrating different perspectives, including political, economic, social, ecological, ethical, health, local, and global considerations. For this reason, the activity presented is considered suitable for promoting the didactics of eco-social education in teacher training.
Overcoming Fear and Improving Public Speaking Skills through Adaptive VR Training
Authors: Jinga Nicolae , Anghel Ana Magdalena , Moldoveanu Florica , Moldoveanu Alin , Morar Anca , Petrescu Livia
Published: May 2024

This paper examines the effectiveness of virtual reality (VR) in training public speaking skills. The fear of public speaking (FPS) is a common problem that can have a significant impact on an individual’s professional and personal life. Traditional therapies for public speaking anxiety have been shown to be effective, but there is growing interest in the use of VR as an alternative or supplement to these therapies. This study aims to investigate the VR medium in improving public speaking skills and to explore the potential mechanisms underlying this effect. A framework was developed with the aim to investigate the possibility of improving public speaking skills through VR. Key features of this framework include the ability to adjust the audience size and alter the dimensions of the room. Additionally, it allows for the modification of initial audience behaviors. One of the innovative aspects is the inclusion of an evolving attention span in the virtual audience, adding a dynamic element to the VR experience. The framework excels in tracking various metrics in real time and has the audience react dynamically based on them. These metrics include movement and voice parameters. The system is designed to present this data as immediate feedback to the user, but also as a summary after a presentation has concluded. After an extensive two-phased testing, the results are discussed. These findings suggest that VR can be an effective means for improving public speaking skills and potentially helping in alleviating fear of public speaking.
A Digital Twin Framework for Simulating Distributed Energy Resources in Distribution Grids
Authors: Værbak Magnus , Billanes Joy Dalmacio , Jørgensen Bo Nørregaard , Ma Zheng
Published: May 2024

As the adoption of distributed energy resources (DERs) grows, the future of electricity distribution systems is confronted with significant challenges. These challenges arise from the transformation of consumers into prosumers and the resulting increased system complexity, leading to more pressure on the distribution grids. To address this complexity, a Digital Twin framework is designed to simulate DERs within distribution grids effectively. This framework is structured around four key modules: DERs, the electricity distribution grid, the energy management system, and the consumers. It incorporates a communication interface to facilitate interactions among these modules and includes considerations for grid topologies and demand-side configurations. The framework allows for the exploration of various DER adoption rates and capacities. The validation of this framework involves case studies on two Danish distribution grids with scenarios incorporating rooftop photovoltaic (PV) systems, batteries, and electric vehicles, considering different combinations of these technologies. The findings demonstrate the framework’s ability to depict the states of the grid, PV systems, electric vehicles, and battery systems with a 10 min resolution over periods ranging from a day to over a decade.
The Application of Magnet Structures to Reduce the Cogging Torque Associated with Fractional Slot Number in Permanent Magnet Generators
Authors: Said Sri Mawar , Nur Tajuddin , Herlina Herlina
Published: May 2024

This study proposes the application of a magnet structure to minimize the cogging torque (CT) and unstable pull in endless magnet generators. The investigation was conducted using an integral slot number of 24 slots and 10 poles, as well as a fractional slot number of 18 slots and 8 poles. The purpose of combining the multi-slot mechanism with pole arc optimization at the magnet edge was to underestimate the peak CT through a reduction in the quantity of tangential flux density. However, the results indicate that CT did not decrease significantly using this method, and this led to the optimization of the edge shape in the magnet structure through the introduction of the surface response method. The combination method’s goal was to ensure a significant reduction in both the integral and fractional slot numbers of the permanent magnet generator. The results show that the CT in the structure with an integral slot number of 24 slots and 10 poles decreased to around 99.4% compared with the baseline structure, while the CT in the structure with a fractional slot number of 18 slots and 8 poles was minimized to 98.8%. This led to the conclusion that the techniques could be combined in structure with any number of integral and fractional slots to reduce CT.
Modeling of Heat and Mass Transfer in Cement-Based Materials during Cement Hydration—A Review
Authors: Klemczak Barbara , Smolana Aneta , Jędrzejewska Agnieszka
Published: May 2024

Cement-based materials encompass a broad spectrum of construction materials that utilize cement as the primary binding agent. Among these materials, concrete stands out as the most commonly employed. The cement, which is the principal constituent of these materials, undergoes a hydration reaction with water, playing a crucial role in the formation of the hardened composite. However, the exothermic nature of this reaction leads to significant temperature rise within the concrete elements, particularly during the early stages of hardening and in structures of substantial thickness. This temperature rise underscores the critical importance of predictive modeling in this domain. This paper presents a review of modeling approaches designed to predict temperature and accompanying moisture fields during concrete hardening, examining different levels of modeling accuracy and essential input parameters. While modern commercial finite element method (FEM) software programs are available for simulating thermal and moisture fields in concrete, they are accompanied by inherent limitations that engineers must know. The authors further evaluate effective commercial software tools tailored for predicting these effects, intending to provide construction engineers and stakeholders with guidance on managing temperature and moisture impacts in early-age concrete.
Grid Model of Energy Consumption Using Random Forest by Integrating Data on the Nighttime Light, Population, and Urban Impervious Surface (2000–2020) in the Guangdong–Hong Kong–Macau Greater Bay Area
Authors: Lei Yanfei , Xu Chao , Wang Yunpeng , Liu Xulong
Published: May 2024

Energy consumption is an important indicator for measuring economic development and is closely related to the atmospheric environment. As a demonstration zone for China’s high-quality development, the Guangdong–Hong Kong–Macao Greater Bay Area imposes higher requirements on ecological environment and sustainable development. Therefore, accurate data on energy consumption is crucial for high-quality green development. However, the statistical data on local energy consumption in China is insufficient, and the lack of data is severe, which hinders the analysis of energy consumption at the metropolitan level and the precise implementation of energy policies. Nighttime light data have been widely used in the inversion of energy consumption, but they can only reflect socio-economic activities at night with certain limitations. In this study, a random forest model was developed to estimate metropolitan-level energy consumption in the Guangdong–Hong Kong–Macao Greater Bay Area from 2000 to 2020 based on nighttime light data, population data, and urban impervious surface data. The estimation results show that our model shows good performance with an R2 greater than 0.9783 and MAPE less than 9%. A long time series dataset from 2000 to 2020 on energy consumption distribution at a resolution of 500 m in the Guangdong–Hong Kong–Macao Greater Bay Area was built using our model with a top-down weight allocation method. The spatial and temporal dynamics of energy consumption in the Greater Bay Area were assessed at both the metropolitan and grid levels. The results show a significant increase in energy consumption in the Greater Bay Area with a clear clustering, and approximately 90% of energy consumption is concentrated in 22% of the area. This study established an energy consumption estimation model that comprehensively considers population, urban distribution, and nighttime light data, which effectively solves the problem of missing statistical data and accurately reflects the spatial distribution of energy consumption of the whole Bay Area. This study provides a reference for spatial pattern analysis and refined urban management and energy allocation for regions lacking statistical data on energy consumption.
Frequency Regulation Adaptive Control Strategy of Wind Energy Storage System for Wind Speed Uncertainty
Authors: Chen Changqing , Li Lixiong
Published: May 2024

In order to reduce the negative influence of wind speed randomness and prediction error on frequency modulation, the reliability of the wind storage system was assessed effectively. In the wind storage frequency modulation system, a state of charge (SOC) adaptive adjustment method for wind speed randomness is proposed. Firstly, through the correlation analysis between the standby capacity of frequency modulation and the output power of wind turbine, the uncertainty of its frequency modulation capacity is revealed. Secondly, in view of the uncertainty of wind turbine frequency modulation, the output power of energy storage frequency modulation is optimized with the goal of minimizing the frequency modulation power deviation of the wind storage front under the framework of model predictive control, and the improved whale optimization algorithm (WOA) is used to solve the problem. Finally, the simulation results show that, under the given 5 min continuous disturbance, the root mean square of frequency regulation of the proposed restoration method is reduced by 56.65% compared to the SOC recovery base point set to 0.5. Under continuous large perturbations, the maximum frequency deviation is reduced by 0.0455 Hz. This effectively shows that this method can not only improve the frequency modulation reliability of wind power system but also improve the continuous frequency modulation capability of energy storage system.
Research on the EMA Control Method Based on Transmission Error Compensation
Authors: Zhang Pan , Shi Zhaoyao , Yu Bo , Qi Haijiang
Published: May 2024

This research investigates the impact of nonlinear clearance factors on position tracking accuracy in the servo drive system of a harmonic reducer. The study introduces a technique for modeling and compensating for transmission errors, thereby improving position tracking accuracy through online compensation combined with an auto-disturbance rejection controller. Initially, the mathematical model of the permanent magnet synchronous motor is outlined, and the current loop and speed loop control models are derived. Subsequently, an electromechanical actuator (EMA) simulation model with clearance is established, and detailed simulation analysis is conducted to verify the impact of clearance on tracking accuracy. A model for online compensation of transmission errors is then developed. Following the principles of active disturbance rejection control (ADRC), a second-order ADRC is formulated for real-time compensation of transmission errors in EMA position mode. Finally, through no-load and load experiments, the change in position tracking error with and without transmission error compensation is compared and analyzed. The results demonstrate that utilizing automatic disturbance rejection control with transmission error compensation achieves the highest position tracking accuracy. Compared to the proportion integration differentiation (PID) control method, the root mean square of position tracking error is reduced by approximately 12.8% and 17.3% under no-load and load conditions, respectively. By compensating for position errors online, the accuracy of the EMA position can be improved.
Pellets Obtained from the Husks of Sunflower Seeds and Beech Sawdust for Comparison
Authors: Lunguleasa Aurel , Olarescu Alin , Spirchez Cosmin
Published: May 2024

The energetic fossil resources of the world have decreased drastically in recent decades, and the quick and efficient solution to replace them is to use renewable biomass resources. This category also includes vegetable biomass, and within it, sunflower seed shells have an important contribution. The present work aimed to analyze the pellets obtained from the husks of sunflower seeds, as lignocellulosic biomass resulting from the production of edible oil, and for comparison, some pellets from beech sawdust were used. The main physical properties (such as moisture content, density, coefficient of densification, etc.), mechanical properties (such as shear strength) and calorific properties (high and low calorific value, calorific density, volatile content and ash content) were determined and statistically analyzed. As the main element of comparison of these types of pellets, the pellets obtained from beech sawdust were used. For the comparison of the pellets obtained from the husks of sunflower seeds, especially to observe their differences compared to the torrefied pellets, charcoal was chosen. The conclusions highlighted the fact that sunflower seed husks are an important source of biomass that can be used to obtain lignocellulosic pellets, and the torrefied pellets obtained from these husks are comparable with the energetic value of charcoal.
Production of Seedlings of Corymbia citriodora Inoculated with Endophytic Bacteria
Authors: de Oliveira Augusto Matias , de Abreu Caique Menezes , Grazziotti Paulo Henrique , de Andrade Gabriel Faria Parreiras , Gomes Jaqueline Vieira , Avelino Natanielly Rodrigues , Menezes June Faria Scherrer , Barroso Gabriela Madureira , dos Santos José Barbosa , da Costa Márcia Regina
Published: May 2024

This study aimed to evaluate the effect of inoculants of endophytic bacteria producing indoleacetic acid (IAA) on the physiological quality of seeds and the production of seedlings of Corymbia citriodora (Hook.) KD Hill & LAS Johnson. In the physiological quality test of the seeds, the treatments used were individual inoculation with Priestia megaterium, Exiguobacterium sibiricum, Pantoea vagans strain 45URP4-1, and Bacillus sp.; joint effect of the four strains (mix); inoculation only with the carrier (cassava starch and activated charcoal); carrier with 1.0 μg mL−1 of IAA; and non-inoculated control without IAA and without a carrier. In the production of seedlings in a greenhouse, the treatments were the same, except for the mix, which was replaced by P. vagans strain 7URP1-6 (Pvs7), as inoculation with the mix increased the number of abnormal seedlings. In the physiological quality test of seeds, seeds inoculated with the bacteria individually did not have the physiological quality impaired and the carrier created a microenvironment around the seeds, benefiting germination percentage, germination speed index, average germination time, and average germination speed. In the greenhouse, seedlings inoculated with Pvs7, P. megaterium and E. sibiricum were taller, with a larger stem diameter and dry mass of shoot, roots, and total. Seeds inoculated with E. sibiricum had higher averages for height, chlorophyll b content, and shoot and total dry mass, as well as a greater ability to colonize the rhizosphere and roots of C. citriodora, resulting in the production of higher-quality seedlings. Inoculation of seeds of C. citriodora with endophytic bacteria proved to be a promising alternative for plant development.
Effects of Simulated Warming on Bacterial Community Structure in Litters of Chinese Fir Based on Displacement Test
Authors: Wu Xiaojian , Li Jiangfei , Zhu Jianing , Jiang Yu , Huang Zhijun , Wu Pengfei , Ma Xiangqing
Published: May 2024

Bacterial communities are vital factors for regulating litter decomposition in forests. With the gradual increase in global climate change, the effects of global warming on the decomposition of forest litter have become a cause for concern. In this study, we used a displacement test to simulate the effects of warming (+2.5, +4.6, and +6.5 °C) on the composition and diversity of bacterial communities in Chinese fir litters based on the natural differences in temperature between the elevation of Wuyi Mountain. Warming significantly increased the abundance and diversity of bacterial communities and altered the functional abundance of bacterial communities. Warming significantly increased the relative abundance of Acidothermus and decreased that of Bacteroidetes and Mucilaginibacter. Structural variations in the bacterial communities were closely related to the chemical properties of the litter. The relative abundance of Planctomycetes exhibited a positive association with nitrogen content and a negative association with cellulose content, whereas phosphorus content was the main driving factor of Acidothermus abundance. Warming increased the complexity of the bacterial community structure, which promoted the decomposition of Chinese fir litter and accelerated nutrient cycling in the Chinese fir plantation ecosystem.
Genotyping-by-Sequencing Study of the Genetic Diversity and Population Structure of the Endangered Plant Tsoongiodendron odorum Chun in China
Authors: Wang Yiping , Li Huihu , Yang Zhijun , Liu Bingyu , Liu Yuanjie , Zhong Yongda
Published: May 2024

Tsoongiodendron odorum Chun is a large evergreen tree in the Magnoliaceae family and an ancient relict species represented by small wild populations. It has excellent material quality, high ornamental value, and scientific significance. However, due to the complicated natural reproduction and notable habitat destruction, its wild populations must be urgently conserved. We used genotyping-by-sequencing to examine 17 natural populations of T. odorum in China, the species’ primary habitat, to better understand the genetic diversity of this species and use its germplasm resources. T. odorum had a very low level of genetic diversity; its mean values for Ho, He, Pi, and PIC were 0.175, 0.123, 0.160, and 0.053, respectively. With an average within-population Fst of 0.023 and an inter-population gene flow Nm of 10.918, population genetic variation was primarily found within populations, demonstrating minute genetic divergence between populations. The 17 natural populations of T. odorum were divided into two major categories: the Fujian populations in eastern China and the Jiangxi, Guangdong, Hunan, and Guangxi populations in central and western China. Our research contributes to the understanding of T. odorum’s genetic diversity and organization and offers a theoretical framework for the species’ conservation, breeding, and selection.
Melanoidin Content Determines the Primary Pathways in Glucose Dark Fermentation: A Preliminary Assessment of Kinetic and Microbial Aspects
Authors: Comparato Carolina Nemeth , de Araujo Matheus Neves , Sakamoto Isabel Kimiko , Fuess Lucas Tadeu , Damianovic Márcia Helena Rissato Zamariolli , da Silva Ariovaldo José
Published: May 2024

Melanoidins are heterogeneous polymers with a high molecular weight and brown color formed during the Maillard reaction by the combination of sugars and amino acids at high temperatures with the potential to inhibit the microbial activity in bioprocesses. This study assessed the impacts of melanoidins on the kinetic of substrate conversion and production of organic acids via dark fermentation using microbial consortia as inoculum. The investigations were carried out in fed-batch reactors using synthetic melanoidins following glucose-to-melanoidin ratios (G/M; g-glucose g−1 melanoidins) of 0.50, 1.50, 1.62, 1.67, and 5.00, also considering a melanoidin-free control reactor. The results showed that melanoidins negatively impacted the kinetics of glucose fermentation by decreasing the first-order decay constant (k1): when dosing equivalent initial concentrations of glucose (ca. 3 g L−1), the absence of melanoidins led to a k1 of 0.62 d−1, whilst dosing 2 g L−1 (G/M = 1.5) and 6.0 g L−1 (G/M = 0.5) of melanoidins produced k1 values of 0.37 d−1 and 0.27 d−1, respectively. The production of butyric and acetic acids was also negatively impacted by melanoidins, whilst the lactic activity was not impaired by the presence of these compounds. Lactate production reached ca. 1000 mg L−1 in G/M = 1.67, whilst no lactate was detected in the control reactor. The presence of melanoidins was demonstrated to be a selective metabolic driver, decreasing the microbial diversity compared to the control reactor and favoring the growth of Lactobacillus. These results highlight the importance of further understanding the impacts of melanoidins on melanoidin-rich organic wastewater bioconversion, such as sugarcane vinasse, which are abundantly available in biorefineries.
Production of Hydrogen with Ruminal Microbiota: Finding Culture Conditions for High Yields
Authors: Gándara-Arteaga Vianca Maribel , Guatemala-Morales Guadalupe María , Martínez-Gómez Álvaro de Jesús , Toriz Guillermo , Pelayo-Ortiz Carlos , Corona-González Rosa Isela
Published: May 2024

Hydrogen is ideal for replacing fossil fuels because upon combustion it generates only water. Dark fermentation (DF) from lignocellulose might be a competitive process for hydrogen production at the industrial scale. However, lignocellulose must be pretreated to obtain fermentable sugars, which is costly and creates pollution. Microorganisms from bovine rumen efficiently degrade lignocellulose. Unfortunately, they have scarcely been explored for the production of hydrogen. Therefore, deeper studies on the culture conditions have to be undertaken to understand the behavior of microbial consortia from the rumen of bovines (MCRB) during hydrogen production. In this work, we evaluated the production of hydrogen by DF with MCRB by varying the incubation time, two culture media (MB and Rhodospirillaceae), headspace (40 and 80 mL), and thermal treatment. It was found that the production of hydrogen was maximum at 16 h MCRB incubation in MB. An amount of 80 mL headspace resulted in a threefold production of hydrogen as compared to 40 mL; the MCRB without heat treatment had a higher H2 yield. The production of hydrogen with 32 MCRB was highly variable, ranging between 21 and 696 mL. Our findings show a different perspective on the treatment of MCRB for the production of hydrogen and give insights on the impact of the culture conditions for increasing hydrogen production.
Unexpected Behavior of a Maltose-Negative Saccharomyces cerevisiae Yeast: Higher Release of Polyfunctional Thiols from Glutathionylated Than from Cysteinylated S-Conjugates
Authors: Simon Margaux , Christiaens Romain , Janssens Philippe , Collin Sonia
Published: May 2024

At present, non-alcoholic and low-alcoholic beers (NABLABs), in addition to their premature sensitivity to oxidation, still suffer from a lack of fruity fermentation aromas. Maltose/maltotriose-negative yeasts offer a highly attractive alternative for creating diversified pleasant aromas and/or eliminating off-flavors in NABLAB production. The aim of this study was to explore the potential of Saccharomyces cerevisiae var. chevalieri, SafBrewTM LA-01 to release fruity polyfunctional thiols from glutathionylated (G-) and cysteinylated (Cys-) precursors. Interestingly, it proved to release free thiols from their glutathionylated S-conjugate much more efficiently (0.34% from G-3-sulfanylhexanol in 15 °P wort after seven days at 24 °C) than the best S. pastorianus strains previously screened (0.13% for lager yeast L7). On the other hand, despite its classification as a S. cerevisiae strain, it showed an inefficient use of cysteinylated precursors, although the release efficiency was slightly higher under NABLAB fermentation conditions (6 °P; 3 days at 20 °C). Under these conditions, as expected, LA-01 consumed only glucose, fructose, and saccharose (0.4% v/v ethanol formation) and produced only low levels of fermentation esters (1.6 mg/L in total) and dimethylsulfide (5 µg/L). The POF+ character of LA-01 also brought significant levels of 4-vinylguaiacol (810 μg/L), which could give to NABLABs the flavors of a white beer.
Characteristics and Immunogenicity of Gluten Peptides in Enzyme-Treated and -Untreated Beers for Celiac Patients
Authors: Decloedt Anneleen , Watson Hellen , Gheysen Godelieve , Van Landschoot Anita
Published: May 2024

The peptidomes from the literature of 24 prolyl-endopeptidase-treated beers during fermentation, declared gluten-free, and 13 untreated beers have been characterised and subjected to an extensive study to investigate their safety for celiac patients. The analysis contains 1996 gluten peptides, ascribed to the treated beers, and 1804 to the untreated beers. The prolyl-endopeptidase-untreated malt beers are hazardous for celiac patients. Peptides of most of these beers showed matches with complete celiac immunogenic motifs, and an additional 28% of the peptides have partial matches with complete immunogenic motifs. On the other hand, after the enzyme treatment during fermentation no celiac hazardous gluten peptides are identified in the treated beers. Due to partial matches with complete celiac immunogenic motifs, 11% potentially hazardous gluten peptides are still identified in the treated beers. Only a maximum of 17% of these peptides can be detected by ELISA analysis. A mass spectrometry analysis or the recently developed method based on G12/A1 monoclonal antibody lateral flow immunochromatographic assay seems necessary to thoroughly reveal the potential risk of the treated beers. The actual immune response of treated beer, described in the literature by the response of the serum antibodies of celiac disease (CD)-active patients and by in vitro immune response, could not be related to the presence of known (partial) CD-immunogenic motifs in the gluten peptides.
Effect of Organic or Inorganic Fertilization on Microbial Flocs Production in Integrated Cultivation of Ulva lactuca with Oreochromis niloticus and Penaeus vannamei
Authors: Carvalho Andrezza , Brandão Hellyjúnyor , Zemor Julio C. , Cardozo Alessandro Pereira , Vieira Felipe N. , Okamoto Marcelo H. , Turan Gamze , Poersch Luís H.
Published: May 2024

Different fertilization regimes in biofloc systems influence the predominance of distinct bacterial populations, impacting water quality and organism performance. This study evaluates the growth and nutrient absorption of the macroalgae Ulva lactuca when cultivated in an integrated system with Penaeus vannamei and Oreochromis niloticus in chemoautotrophic and heterotrophic systems. The experiment lasted 45 days and comprised two treatments, each with three replicates: chemoautotrophic—utilizing chemical fertilizers; heterotrophic—employing inoculum from mature biofloc shrimp cultivation, supplemented with organic fertilizers. Each treatment consisted of three systems, each containing a 4 m3 tank for shrimp, 0.7 m3 for tilapia, and 0.35 m3 for macroalgae, with continuous water circulation between tanks and constant aeration. Water quality analyses were carried out during the experiment, as were the performances of the macroalgae and animals. The data were subjected to a statistical analysis. Results revealed an increase in macroalgae biomass and the removal of nitrate (57%) and phosphate (47%) during cultivation, with a higher specific growth rate observed in the chemoautotrophic treatment. Nonetheless, the heterotrophic treatment exhibited higher levels of protein in the macroalgae (18% dry matter) and phosphate removal rates (56%), along with superior maintenance of water quality parameters. Tilapia performance varied across treatments, with a higher final weight and weight gain recorded in the heterotrophic treatment. The recycling of water from an ongoing biofloc cultivation with organic fertilization demonstrated viability for macroalgae cultivation within an integrated system involving shrimp and fish.
Exploring Seasonal Variations in Fish Communities: A Study of the Yellow River Estuary and Its Adjacent Waters Using eDNA and Trawl Surveys
Authors: Wang Xiaoyang , Li Fan , Shao Fei , Song Hongjun , Song Na , Zhang Xiaomin , Zhao Linlin
Published: May 2024

The Yellow River Estuary and its adjacent waters serve as crucial spawning, foraging, and nursery areas for marine organisms, possessing abundant biological resources. Monitoring fish communities provides a baseline for implementing the sustainable utilization of marine resources. In this study, data were collected from 15 spring surface and bottom sites and 17 summer surface sites using eDNA and trawl surveys. The results showed that 37, 40, and 35 fish species were detected using eDNA in the spring (surface and bottom) and summer (surface), respectively, with 38 fish species caught during summer trawling. The dominant species mainly belonged to Engraulidae of Clupeiformes in the spring and Gobiidae of Perciformes in the summer, characterized by smaller-sized, short-lived, and pelagic fish species. The summer surface communities exhibited higher diversity than the spring surface and bottom communities. NMDS analysis revealed a degree of seasonal differences in fish communities and that there may be a lack of vertical stratification in the spring communities. The pH and DO were identified as the key environmental factors affecting the fish community. Additionally, the combination of eDNA and trawl surveys was regarded as a superior survey method. Our study provides valuable information for understanding seasonal fish communities in the Yellow River Estuary and its adjacent waters, contributing to fishery resource management and conservation in the region.
Insights into the Correlation between Microbial Community Succession and Pericarp Degradation during Pepper (Piper nigrum L.) Peeling Process via Retting
Authors: Fu Yuting , Chen Shuai , Wang Xinjun , Wang Lu , Wang Zexin , Cheng Yanfei , Liu Yuyi , Zhang Lin , Liu Sixin , Kang Jiamu , Li Congfa
Published: May 2024

White pepper, used both as a seasoning in people’s daily diets and as a medicinal herb, is typically produced by removing the pericarp of green pepper through the retting process. However, the mechanism of the retting process for peeling remains unclear. Therefore, this study aimed to investigate the changes in physicochemical factors, microbial community succession effects, and metabolites of the pepper pericarp during the pepper peeling process. The findings indicated that pre-treatment involving physical friction before the retting process effectively reduced the production time of white pepper. During the retting process, the pectinase activity increased, leading to a decrease in the pectin content in the pepper pericarp. There was a significant correlation observed between the changes in pH, pectin content, and peeling rate and the Shannon diversity index of bacteria and fungi. Prevotella, Lactococcus, and Candida were the dominant microbial genera during the retting. The functional predictions suggested that the monosaccharides degraded from the pepper pericarp could have been utilized by microbes through sugar metabolism pathways. Metabolomic analysis showed that the metabolic pathways of carbohydrates and amino acids were the main pathways altered during the pepper peeling process. The verification experiment demonstrated that the degradation of pectin into galacturonic acid by polygalacturonase was identified as the key enzyme in shortening the pepper peeling time. The structure of the pepper pericarp collapsed after losing the support of pectin, as revealed by scanning electron microscopy. These results suggest that the decomposition of the pepper pericarp was driven by key microbiota. The succession of microbial communities was influenced by the metabolites of the pepper pericarp during retting. These findings provide new insights into the retting process and serve as an important reference for the industrial production of white pepper.
Comparative Metabolome Profiling for Revealing the Effects of Different Cooking Methods on Glutinous Rice Longjing57 (Oryza sativa L. var. Glutinosa)
Authors: Guo Zhenhua , Cai Lijun , Liu Chuanxue , Zhang Yunjiang , Wang Linan , Liu Hao , Feng Yanjiang , Pan Guojun , Ma Wendong
Published: May 2024

Glutinous rice (GR), an important food crop in Asia, provides prolonged energy for the human body due to its high amylopectin content. The non-volatile metabolites generated by different cooking methods that affect the nutritional value and color of GR are still poorly understood. Herein, a widely targeted metabolomics approach was used to understand the effects of different cooking methods (steaming, baking, and frying) on the metabolite profiles of GR. Compared with other treatments, steamed GR had a brighter color and significantly lower contents of total sugar, starch, amylopectin, and amylose, at 40.74%, 14.13%, 9.78%, and 15.18%, respectively. Additionally, 70, 108, and 115 metabolites were significantly altered in the steaming, baking, and frying groups respectively, and amino acid and carbohydrate metabolism were identified as the representative metabolic pathways based on KEGG annotations. Further evaluation of 14 amino acids and 12 carbohydrates in steamed GR, especially 4-aminobutyric acid, suggested its high nutraceutical value. Additionally, multivariate analysis indicated that total sugar content, amylose content, beta-alanine methyl ester hydrochloride, and 4-aminobutyric acid played a critical role in color formation in raw and cooked GR. Finally, the levels of major amino acids and carbohydrates were quantified by conventional methods to verify the reliability of the metabolome. Consequently, this in-depth understanding of metabolite profiling in normal cooking methods has provided a foundation for the processing of GR products.