bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovation and Evaluations of 3D Printing Resins Modified with Zirconia Nanoparticles and Silver Nanoparticle-Immobilized Halloysite Nanotubes for Dental Restoration
Authors: Darbandi Karwan Rashid , Amin Bassam Karem
Published: March 2024

Additive manufacturing technologies can be used to fabricate 3D-printed dental restorations. In this study, we evaluated the effectiveness of the functionalized loading of zirconium dioxide (ZrO2) nanoparticles and silver-nanoparticles-immobilized halloysite (HNC/Ag) nanotubes into 3D printing resins. We created 3D printing resins by adding different mass fractions of ZrO2 and HNC/Ag. First, six groups of samples containing ZrO2 were prepared, comprising five groups with different mass fractions and one control group of ZrO2 containing 1 to 16 %wt. Different mass fractions of HNC/Ag fillers were combined with the ZrO2 mixture and resin at the ideal ratio from 1 to 7.5 %wt. The mechanical characteristics of 3D resin that we assessed were the flexural strength, flexural modulus, fracture toughness, and the microhardness. Additional rates of ZrO2 4 %wt. and HNC/Ag 5 %wt. significantly increase the flexural strength, flexural modulus, and fracture toughness compared to the control group (p < 0.001). ZrO2 16 %wt. and HNC/Ag 5 %wt. were found to be significantly harder compared to the other groups (p < 0.001). The amounts of NPs that can be added to 3D printing resin modification appears to be 4 %wt., and HNC/Ag 5 %wt. can be advantageous in terms of fracture toughness, flexural strength, and flexural modulus. All additions of nanoparticles raised the resin’s hardness.
A Facile Method for the Evaluation of the Adhesion Strength of Strain Gauges
Authors: Zhang Zhibo , Long Dongfang , Yang Qinghao
Published: March 2024

The adhesion of strain gauges (SGs) onto the underlying spring element plays an important role not only during the fabrication of the SG sensors but also for the final performance of the sensors. A novel and facile method for the evaluation of the adhesion strength of SGs is proposed, tested, and validated in this paper. In comparison with the traditional peel tester method, this method demonstrated both higher reliability and efficiency, especially from an industrial manufacturing point of view. The five-grade adhesion strength, with adhesion strength decreased from Grade 1 (G1) to Grade 5 (G5), results were corroborated by the classical pull-out adhesion testing method with satisfactory consistency and can be employed in the quick evaluation and monitoring of the adhesion strength. The easiness, convenience, and reliability of the method promises a great potential application in the industrial testing and manufacturing of SG sensors.
Pre-Polymer Chain Length: Influence on Permanent Memory Effect of PDLC Devices
Authors: Mouquinho Ana , Barros Maria Teresa , Sotomayor João
Published: March 2024

This study delved into the correlation between the chain length of PEG polymerizable oligomers and the electro-optical properties exhibited by the resultant PDLC films. A range of di(meth)acrylate oligomers derived from polyethylene glycol with varying molecular weights (Mn = 1000, 2000, 4000, and 6000 g mol−1) was synthesized for incorporation as the polymer matrix in PDLC devices. Comprehensive analyses employing 1H-NMR, 13C-NMR, and MALDI-TOF mass spectroscopy were conducted to validate the structure and purity of the synthesized products. The investigation revealed a significant influence of pre-polymer molecular chain length on the thermal properties of the polymer, including amorphousness and crystallinity, which in turn impact the permanent memory effect. Specifically, it was observed that amorphous PEG polymers serve as an ideal matrix for fostering the permanent memory effect in PDLCs. Among the polymerizable PEG oligomers examined, those with a molecular weight of 1000 g/mol yielded polymer chains existing in an amorphous state, exhibiting a glass transition temperature lower than room temperature (−50 °C). This characteristic imparts flexibility and mobility to the polymer matrix chains, facilitating a 37% permanent memory effect. Conversely, longer polymer chains lead to the formation of crystal aggregates, resulting in semi-crystalline polymer matrices. This reduces the malleability of the polymer chains, thereby nullifying the permanent memory effect in the corresponding PDLC devices.
High-Performance N-Polar GaN/AlGaN Metal–Insulator–Semiconductor High-Electron-Mobility Transistors with Low Surface Roughness Enabled by Chemical–Mechanical-Polishing-Incorporated Layer Transfer Technology
Authors: Guo Bohan , Yu Guohao , Zhang Li , Zhou Jiaan , Wang Zheming , Xing Runxian , Yang An , Li Yu , Liu Bosen , Zeng Xiaohong , Du Zhongkai , Deng Xuguang , Zeng Zhongming , Zhang Baoshun
Published: March 2024

This article presents the utilization of the chemical–mechanical polishing (CMP) method to fabricate high-performance N-polar GaN/AlGaN metal–insulator–semiconductor high-electron-mobility transistors (MIS-HEMTs) through layer transfer technology. The nucleation and buffer layers were removed via CMP to attain a pristine N-polar GaN surface with elevated smoothness, featuring a low root-mean-square (RMS) roughness of 0.216 nm. Oxygen, carbon, and chlorine impurity elements content were low after the CMP process, as detected via X-ray photoelectron spectroscopy (XPS). The electrical properties of N-polar HEMTs fabricated via CMP exhibited a sheet resistance (Rsh) of 244.7 Ω/sq, a mobility of 1230 cm2/V·s, and an ns of 2.24 × 1013 cm−2. Compared with a counter device fabricated via inductively coupled plasma (ICP) dry etching, the CMP devices showed an improved output current of 756.1 mA/mm, reduced on-resistance of 6.51 Ω·mm, and a significantly reduced subthreshold slope mainly attributed to the improved surface conditions. Meanwhile, owing to the MIS configuration, the reverse gate leakage current could be reduced to as low as 15 μA/mm. These results highlight the feasibility of the CMP-involved epitaxial layer transfer (ELT) technique to deliver superior N-polar GaN MIS-HEMTs for power electronic applications.
Walking with the Atoms in a Chemical Bond: A Perspective Using Quantum Phase Transition
Authors: Kais Sabre
Published: March 2024

Phase transitions happen at critical values of the controlling parameters, such as the critical temperature in classical phase transitions, and system critical parameters in the quantum case. However, true criticality happens only at the thermodynamic limit, when the number of particles goes to infinity with constant density. To perform the calculations for the critical parameters, a finite-size scaling approach was developed to extrapolate information from a finite system to the thermodynamic limit. With the advancement in the experimental and theoretical work in the field of ultra-cold systems, particularly trapping and controlling single atomic and molecular systems, one can ask: do finite systems exhibit quantum phase transition? To address this question, finite-size scaling for finite systems was developed to calculate the quantum critical parameters. The recent observation of a quantum phase transition in a single trapped 171 Yb+ ion indicates the possibility of quantum phase transitions in finite systems. This perspective focuses on examining chemical processes at ultra-cold temperatures, as quantum phase transitions—particularly the formation and dissociation of chemical bonds—are the basic processes for understanding the whole of chemistry.
Solar Photovoltaic Cooker with No Electronics or Battery
Authors: Lecuona-Neumann Antonio , Nogueira-Goriba José I. , Famiglietti Antonio , Rodríguez-Hidalgo María del Carmen , Boubour Jean
Published: March 2024

The paper offers innovative cooking utensil designs for remote, isolated, and even peri-urban communities at a low price, with high reliability and simple construction. It can alleviate energy poverty and improve food security. This utensil uses only local solar energy directly and allows comfortable indoor cooking. This paper provides the design principles of a solar cooker/frying pan or generic heater, based on a PV panel or a plurality of them, which are directly connected to a plurality of Positive Thermal Coefficient (PTC) resistors to match the power. PTCs are nowadays produced in massive quantities and are widely available at low cost. The proposed device does not require an electronic controller or a battery for its operation. The aim is for family use, although the design can be easily scaled to a larger size or power, maintaining its simplicity. Electric heating inside or attached to the cooking pot, plus the temperature self-limiting effect of PTCs, allows for thermally insulating the cooking pot from its outside using ordinary materials. Insulation enhances energy efficiency during cooking and keeps cooked food warm for a long time. Clean development would receive a significant impulse with its application. A simple mathematical model describes its functioning and states guidelines for adequate design. Its results indicate a successful proof of concept and high efficiency both for water and oil as representatives of cooking.
Analysis of the Flow Capacity of Variable Cycle Split Fans at the Middle Speed
Authors: An Guangfeng , Zhou Rui , Yu Xianjun , Liu Baojie , Wu Guanghan
Published: March 2024

The next-generation variable cycle engine imposes stricter requirements on a fan’s flow capacity at the middle speed. To tackle this challenge, the implementation of split fans presents as a potential solution. In the present study, we conducted numerical simulations using the commercial software NUMECA to investigate the aerodynamic performance variation with bypass ratios for variable cycle split fans in “1 + 2” and “2 + 1” configurations at 80% rpm. The results indicate that the flow capacity of the split fans exhibits an increasing trend with a rise in the bypass ratio at 80% rpm and subsequently stabilizes upon reaching a certain bypass ratio. Specifically, the flow capacity of the “2 + 1” split fans is particularly stronger at the small bypass ratios, whereas the “1 + 2” split fans exhibit superior maximum flow capacity at the high bypass ratios. Additionally, there is a significantly faster increase in the flow capacity of the “1 + 2” split fans compared to that of the “2 + 1” split fans. Furthermore, when the flow capacity of the split fans reaches its maximum, both the efficiency and stall margin achieve their optimal values, indicating that the corresponding bypass ratio is optimal.
Depolymerization of PMMA-Based Dental Resin Scraps on Different Production Scales
Authors: Ribeiro Haroldo Jorge da Silva , Ferreira Armando Costa , Ferreira Caio Campos , Pereira Lia Martins , Santos Marcelo Costa , Guerreiro Lauro Henrique Hamoy , Assunção Fernanda Paula da Costa , da Mota Sílvio Alex Pereira , Castro Douglas Alberto Rocha de , Duvoisin Sergio , Borges Luiz Eduardo Pizarro , Machado Nélio Teixeira , Bernar Lucas Pinto
Published: March 2024

This research explores the depolymerization of waste polymethyl methacrylate (PMMAW) from dental material in fixed bed semi-batch reactors, focusing on three production scales: laboratory, technical and pilot. The study investigates the thermal degradation mechanism and kinetics of PMMAW through thermogravimetric (TG) and differential scanning calorimetry (DSC) analyses, revealing a two-step degradation process. The heat flow during PMMAW decomposition is measured by DSC, providing essential parameters for designing pyrolysis processes. The results demonstrate the potential of DSC for energetic analysis and process design, with attention to standardization challenges. Material balance analysis across the production scales reveals a temperature gradient across the fixed bed negatively impacting liquid yield and methyl methacrylate (MMA) concentration. Reactor load and power load variables are introduced, demonstrating decreased temperature with increased process scale. The study identifies the influence of temperature on MMA concentration in the liquid fraction, emphasizing the importance of controlling temperature for efficient depolymerization. Furthermore, the research highlights the formation of aromatic hydrocarbons from the remaining char, indicating a shift in liquid composition during the depolymerization process. The study concludes that lower temperatures below 450 °C favor liquid fractions rich in MMA, suggesting the benefits of lower temperatures and slower heating rates in semi-batch depolymerization. The findings contribute to a novel approach for analyzing pyrolysis processes, emphasizing reactor design and economic considerations for recycling viability. Future research aims to refine and standardize the analysis and design protocols for pyrolysis and similar processes.
Data-Driven Management Systems for Wave-Powered Renewable Energy Communities
Authors: Iqbal Saqib , Mehran Kamyar
Published: March 2024

This research focus on the essential task of precise prediction for power generation and energy consumption of wave energy converters (WECs) within the framework of contemporary wave-powered renewable energy sources (RESs). Utilizing real-time wave data, we introduce a deep learning methodology featuring a long short-term memory (LSTM) model. Additionally, we propose an online management system for RESs aimed at optimizing interactions among WECs, energy storage systems (ESSs), super capacitor (SC), and load. This approach leads to significant enhancements in mean square error (MSE) for critical variables such as wave height, time period, and direction, improving predictive accuracy by factors of 8.37, 9.30, and 16.14, respectively. Through diverse scenario-based experimental evaluations, our solution exhibits competitive performance when compared to benchmark strategies and ideal solutions. These findings underscore the potential of the LSTM-NN model to advance the efficiency and reliability of wave energy forecasting and management systems. As wave energy technology evolves, this study contributes to ongoing efforts to enhance practical applicability, especially in coastal regions with substantial wave energy potential.
An Investigation of Tidal Stream Turbine Wake Development Using Modified BEM–AD Model
Authors: Pang Chee M. , Kennedy David M. , O’Rourke Fergal
Published: March 2024

Tidal stream turbines (TST) are a promising option for electricity generation to meet the ever-increasing demand for energy. The actuator disk (AD) method is often employed to represent a TST, to evaluate the TST operating in a tidal flow. While this method can effectively reduce the computational cost and provide accurate prediction of far-wake flow conditions, it falls short of fully characterising critical hydrodynamics elements. To address this limitation, a hybrid method is implemented by coupling AD with the blade element momentum (BEM) theory, using detailed performance data, such as thrust, to enhance the prediction of the wake effects. This work focuses on the development of a hybrid BEM–AD method using Reynolds-Averaged Navier–Stokes (RANS) turbulence models within computational fluid dynamics (CFD). Two variations and a hybrid modification of an AD model are presented in this paper. The first modified variation is a velocity variation that takes into account velocity profile inflow into the disk’s configuration. The second modified variation is a radial variation that integrates the blade element theory into the disk’s configuration. The hybrid modified model combines both the velocity profiles influenced and blade element theory in the design and analysis of the actuator disk. Several key investigations on some of the pre-solver parameters are also investigated in this research such as the effect of changing velocity and radial distance on the porosity and loss coefficient of the actuator disk performance. Importantly, this work provides an improved method to evaluate the key wake effects from a TST array which is crucial to determine the power performance of the TST array.
Multiple Factors Coupling Probability Calculation Model of Transmission Line Ice-Shedding
Authors: Pan Hao , Zhou Fangrong , Ma Yi , Ma Yutang , Qiu Ping , Guo Jun
Published: March 2024

After a transmission line is covered by ice in winter, ice-shedding and vibration occurs under special meteorological and external dynamic conditions, which leads to intense transmission line shaking. Transmission line ice-shedding and vibration often cause line flashover trips and outages. In January 2018, three 500 kV transmission lines, namely, the 500 kV Guanli line, the 500 kV Dushan line, and the 500 kV Guanqiao line, tripped and cut off due to ice-shedding and vibration in Anhui province, seriously threatening the safe operation of a large power grid. Current studies mainly focus on analyzing the influence factors and characteristics of line ice-shedding and investigating suppression measures, but they only analyze the correlation between each influencing factor and icing or shedding, and do not consider the coupling effects between multiple factors. In this paper, the key influencing factors and the probability distribution of transmission line ice-shedding were analyzed, and a multiple-factor coupling fault probability calculation model of line ice-shedding based on Copula function was proposed. The fault probability was calculated directly by considering multiple influence factors at the same time, which effectively overcame the error caused by multi-factor transformation in fuzzy membership degree and other methods. It provided an important decision-making basis for preventing and controlling transmission line ice-shedding faults.
Airfoil Control of Small Wind Turbines
Authors: Sesalim Dean , Naser Jamal
Published: March 2024

Although the latest technologies have achieved outstanding improvements in the energy capture efficiency of wind power turbines, lack of cost effectiveness remains a major disadvantage. The problem lies in the limitation of operating effectively over a wide range of wind speeds. A variety of wind turbines have implemented variable control systems such as pitch control to extend the range of wind speeds at which the turbines can operate efficiently. These systems, however, have negatively impacted on the cost of wind energy. This paper investigates the possibility of achieving variable speed control performance by means of airfoil design for an uncontrolled wind turbine. Using computational fluid dynamics (CFD), this study optimizes the maximum thickness location of the S809 airfoil profile implemented in the National Renewable Energy Laboratory (NREL) Phase VI wind turbine blades to verify the design parameter most relevant to the objective of this research. The aerodynamic characteristics of the resulting design are compared to those of the baseline model. The results do indeed indicate the ability of the airfoil design to improve the power curve without the use of control systems.
Economic Pricing in Peer-to-Peer Electrical Trading for a Sustainable Electricity Supply Chain Industry in Thailand
Authors: Leelasantitham Adisorn , Wongsamerchue Thammavich , Sukamongkol Yod
Published: March 2024

The state-owned power Electricity Generating Authority of Thailand (EGAT), a monopoly market in charge of producing, distributing, and wholesaling power, is the focal point of Thailand’s electricity market. Although the government has encouraged people to install on-grid solar panels to sell electricity as producers and retail consumers, the price mechanism, i.e., purchasing price and selling prices, is still unilaterally determined by the government. Therefore, we are interested in studying the case where blockchain can be used as a free trading platform. Without involving buying or selling from the government, this research presents a model of fully traded price mechanisms. Based on the study results of the double auction system, data on buying and selling prices of electrical energy in Thailand were used as the initial data for the electricity peer-to-peer free-trading model. Then, information was obtained to analyze the trading price trends by using the law of demand and supply in addition to the principle of the bipartite graph. The price trend results agree well with those of price equilibrium equations. Therefore, we firmly believe that the model we offer can be traded in a closed system of free-trade platforms. In addition, the players in the system can help to determine the price trend that will occur according to various parameters and will cause true fairness in the sustainable electricity supply chain industry in Thailand.
Integrating Industry 4.0 and 5.0 Innovations for Enhanced Energy Management Systems
Authors: Introna Vito , Santolamazza Annalisa , Cesarotti Vittorio
Published: March 2024

Industry 4.0 and Industry 5.0 have introduced a lot of innovative technologies in industrial plants, transforming them into complex digital systems. On the other hand, the importance of Energy Management Systems in industrial plants is growing for both sustainability and economic reasons, but the opportunity of Industry 4.0/5.0 technologies in enhancing energy management systems is not fully understood. Thus, this paper analyzes how Industry 4.0/5.0 technologies can be applied to meet the requirements of Energy Management Systems, focusing on each aspect such as design, monitoring, control, and budget planning. It identifies additional opportunities that arise with different levels of technological implementation, suggesting organic implementation steps. The final aim is to provide a comprehensive framework for fostering a strategic and conscious implementation approach of these tools in the Energy Management Systems of industrial plants, giving clear and comprehensive suggestions.
Forecasting Energy Poverty in European Countries: The Effect of Increasing Energy Commodities Prices
Authors: Carfora Alfonso , Scandurra Giuseppe
Published: March 2024

The impact of the global COVID-19 pandemic has been devastating in many countries, increasing household energy poverty. Lockdown measures have brought the EU economies into recession phases and forced people to stay confined to their homes, aggravating these issues. From the second half of 2021, when the worst seemed behind us, a new threat has appeared threatening economic recovery: the inflationary process in energy prices. This paper aims to verify the effects on energy poverty in European countries following the economic crisis generated by COVID-19 and the current inflationary scenario due to the increase in energy commodity prices through dynamic factor models, estimating the time it will take for energy poverty to return to levels before the shocks that occurred over the past two years. The outcomes show that the overall rise in energy prices (in particular gas) that unexpectedly affected European countries modifies the forecast scenarios, delaying, at best, the first improvements, initially expected as early as 2021, until after 2022.
Real Options Volatility Surface for Valuing Renewable Energy Projects
Authors: González-Muñoz Rosa-Isabel , Molina-Muñoz Jesús , Mora-Valencia Andrés , Perote Javier
Published: March 2024

Real options analysis is an adequate tool with which to value companies and projects under investment uncertainty. Nevertheless, the estimation of the volatility to be employed in the valuation procedure is a challenging task. The volatility parameter not only affects the investment value, but is also important in strategic decision-making. The aim of this paper is to provide a suitable methodology for the estimation of volatility in real option project valuation, with a focus on renewable energy projects. Our procedure is a straightforward extension of the implied volatility methodology employed for financial options; however, our proposal considers the debt-to-equity ratio instead of the moneyness or strike price. Thus, the volatility of the project is the implied volatility obtained from the volatility surface of comparable firms for a certain valuation date and the given debt-to-equity relation of a renewable project. Furthermore, the natural spline model is utilized to calibrate the volatility surface for real option valuation purposes. The empirical results demonstrate that the implied volatility ranges from 3.37% to 113.78%, with median values between 16.42% and 47.10%, in the period from January 2014 to December 2020, for our research study. Finally, we consider that our proposal is a natural and straightforward manner in which to estimate the implied volatility for projects under investment uncertainty, since real option valuation is based on the same idea and tools used in financial option pricing.
A Review on Digital Twins and Its Application in the Modeling of Photovoltaic Installations
Authors: Angelova Dorotea Dimitrova , Fernández Diego Carmona , Godoy Manuel Calderón , Moreno Juan Antonio Álvarez , González Juan Félix González
Published: March 2024

Industry 4.0 is in continuous technological growth that benefits all sectors of industry and society in general. This article reviews the Digital Twin (DT) concept and the interest of its application in photovoltaic installations. It compares how other authors use the DT approach in photovoltaic installations to improve the efficiency of the renewable energy generated and consumed, energy prediction and the reduction of the operation and maintenance costs of the photovoltaic installation. It reviews how, by providing real-time data and analysis, DTs enable more informed decision-making in the solar energy sector. The objectives of the review are to study digital twin technology and to analyse its application and implementation in PV systems.
Characterization of Change in Tree Cover State and Condition over the Conterminous United States
Authors: Dwomoh Francis K. , Auch Roger F.
Published: March 2024

Variability in the effects of disturbances and extreme climate events can lead to changes in tree cover over time, including partial or complete loss, with diverse ecological consequences. It is therefore critical to identify in space and time the change processes that lead to tree cover change. Studies of change are often hampered by the lack of data capable of consistently detecting different types of change. Using the Landsat satellite record to create a long time-series of land cover and land cover change, the U.S. Geological Survey Land Change Monitoring Assessment and Projection (LCMAP) project has made an annual time series of land cover across the conterminous United States for the period 1985 to 2018. Multiple LCMAP products analyzed together with map validation reference plots provide a robust basis for understanding tree cover change. In LCMAP (Collection 1.2), annual change detection is based on harmonic model breaks calculated at each Landsat pixel from the Continuous Change Detection and Classification (CCDC) algorithm. The results showed that the majority of CCDC harmonic model breaks (signifying change) indicated partial tree cover loss (associated with management practices such as tree cover thinning) as compared to complete tree cover loss (associated with practices like clearcut harvest or fire disturbance). Substantially fewer occurrences of complete tree cover loss were associated with change in land cover state. The area of annual tree cover change increased after the late 1990s and stayed high for the rest of the study period. The reference data showed that tree harvest dominated across the conterminous United States. The majority of tree cover change occurred in evergreen forests. Large estimates of disturbance-related tree cover change indicated that tree cover loss may have previously been underreported due to omission of partial tree cover loss in prior studies. This has considerable implications for forest carbon accounting along with tracking ecosystem goods and services.
A Comprehensive Analysis of Vegetation Dynamics and Their Response to Climate Change in the Loess Plateau: Insight from Long-Term kernel Normalized Difference Vegetation Index Data
Authors: He Qingyan , Yang Qianhua , Jiang Shouzheng , Zhan Cun
Published: March 2024

The Loess Plateau (LP) is a typical climate-sensitive and ecologically delicate area in China. Clarifying the vegetation–climate interaction in the LP over 40+ years, particularly pre- and post-Grain to Green Program (GTGP) implementation, is crucial for addressing potential climate threats and achieving regional ecological sustainability. Utilizing the kernel Normalized Difference Vegetation Index (kNDVI) and key climatic variables (precipitation (PRE), air temperature (TEM), and solar radiation (SR)) between 1982 and 2022, we performed an extensive examination of vegetation patterns and their reaction to changes in climate using various statistical methods. Our findings highlight a considerable and widespread greening on the LP from 1982 to 2022, evidenced by a kNDVI slope of 0.0020 yr−1 (p < 0.001) and a 90.9% significantly increased greened area. The GTGP expedited this greening process, with the kNDVI slope increasing from 0.0009 yr−1 to 0.0036 yr−1 and the significantly greened area expanding from 39.1% to 84.0%. Over the past 40 years, the LP experienced significant warming (p < 0.001), slight humidification, and a marginal decrease in SR. Post-GTGP implementation, the warming rate decelerated, while PRE and SR growth rates slightly accelerated. Since the hurst index exceeded 0.5, most of the vegetated area of the LP is expected to be greening, warming, and humidification in the future. In the long term, 75% of the LP vegetated area significantly benefited from the increase in PRE, especially in relatively dry environments. In the LP, 61% of vegetated areas showed a positive correlation between kNDVI and TEM, while 4.9% exhibited a significant negative correlation, mainly in arid zones. SR promoted vegetation growth in 23% of the vegetated area, mostly in the eastern LP. The GTGP enhanced the sensitivity of vegetation to PRE, increasing the area corresponding to a significant positive correlation from 15.3% to 59.9%. Overall, PRE has emerged as the dominant climate driver for the vegetation dynamics of the LP, followed by TEM and SR. These insights contribute to a comprehensive understanding of the climate-impact-related vegetation response mechanisms, providing guidance for efforts toward regional sustainable ecological development amid the changing climate.
Variation and Correlation among Fine Root Traits of Desert Plants in Arid Areas of Northwest China
Authors: Ma Jing , Wang Taotao , Wang Hongyong , Yang Jie , Xie Tingting , Zhang Zhengzhong , He Cai , Shan Lishan
Published: March 2024

The variation and correlation among desert plant traits are helpful to understanding the adaptation strategies of plants to the environment and the mechanism of community assembly. However, the diversity and covariation among fine root traits of desert plants and their phylogenetic relationships remain unclear. Principal component analysis, Pearson’s correlations, phylogenetic independent comparison, mixed linear model, and variance decomposition were used to investigate the variation and correlation among 10 fine root traits of 25 common desert plants in arid areas. The results are as follows: (1) We found that all fine root traits varied more among interspecific variation, with the coefficient of variation ranging from 21.83% to 105.79%. Most traits were predominantly shaped by interspecific variation, whereas root phosphorus content (RPC) and intraspecific variation in root carbon/nitrogen ratio (RCN) were more important. (2) Root traits were correlated with four axes of variation. Root nitrogen content (RNC) correlated positively with root diameter (AD) and tissue density (RTD) but negatively with specific root length (SRL), which was inconsistent with the inference of the root economics spectrum (RES). (3) Covariance and trade-off strategies of fine root traits in different life forms of plants were different. Herb RNC was negatively correlated with SRL and positively correlated with AD, while this relationship did not exist in shrubs. Moreover, shrub AD was negatively correlated with RTD, but herbs showed no significant correlation. (4) Influenced by phylogenetic factors, fine root traits exhibited a covariant or trade-off pattern. Taken together, fine root traits were predominantly shaped by interspecific variation, but intraspecific variation also played a significant role. Concurrently, distinct patterns in fine root covariation and trade-off strategies among different life forms of plants were also observed. Future studies should explore the variation and correlation among traits at different scales within and between species from the perspective of life form.
Efficient Secretory Expression of Leghemoglobin in Saccharomyces cerevisiae
Authors: Huang Yiyun , Zhou Jingwen , Li Jianghua , Du Guocheng , Chen Jian , Zhao Xinrui
Published: March 2024

Leghemoglobin (LegH) is a plant-derived hemoglobin that can be used as a food additive to confer red color and meat flavor to plant-based meat products. Although LegH has been expressed in Saccharomyces cerevisiae, the productivity is low at the shaking-flask level, and the downstream process of purification is complicated. Herein, the intracellular expression of LegH reached 151.2 mg/L through initial promoter modification. Then, the fermentation strategy was optimized, and the titer of LegH reached 544.8 mg/L (5.2 mg/L/OD600 per unit yield) in the two-stage fed-batch fermentation in a 5-L fermenter. After the modification of signal peptide and knockout of proteases, the secretory expression of LegH was achieved in recombinant S. cerevisiae, and the final secretory titer of LegH reached 88.5 mg/L at the 5-L fermenter level. Based on the results of this study, the secreted LegH can be widely applied in the fields of food processing and biocatalysis in the future.
Identification and Transcriptome Analysis of a Novel Allelic Mutant of NAL1 in Rice
Authors: Wang Yang , Xu Wanxin , Liu Yan , Yang Jie , Guo Xin , Zhang Jiaruo , Pu Jisong , Chen Nenggang , Zhang Wenfeng
Published: March 2024

Leaf morphology is a crucial aspect of plant architecture, yet the molecular mechanisms underlying leaf development remain incompletely understood. In this study, a narrow leaf mutant, m625, was identified in rice (Oryza sativa L.), exhibiting pleiotropic developmental defects. Pigment measurement revealed reduced levels of photochromic pigments in m625. Cytological analysis demonstrated that the m625 gene affected vascular patterns and cell division. Specifically, the narrowing of the leaf was attributed to a decrease in small vein number, shorter vein spacing, and an abnormal V-shaped arrangement of bulliform cells, while the thickening was caused by longer leaf veins, thicker mesophyll cells, and an increased number of parenchyma cell layers. The dwarf stature and thickened internode were primarily due to shortened internodes and an increase in cell layers, respectively. Positional cloning and complementation assays indicated that the m625 gene is a novel allele of NAL1. In the m625 mutant, a nucleotide deletion at position 1103 in the coding sequence of NAL1 led to premature termination of protein translation. Further RNA-Seq and qRT-PCR analyses revealed that the m625 gene significantly impacted regulatory pathways related to IAA and ABA signal transduction, photosynthesis, and lignin biosynthesis. Moreover, the m625 mutant displayed thinner sclerenchyma and cell walls in both the leaf and stem, particularly showing reduced lignified cell walls in the midrib of the leaf. In conclusion, our study suggests that NAL1, in addition to its known roles in IAA transport and leaf photosynthesis, may also participate in ABA signal transduction, as well as regulate secondary cell wall formation and sclerenchyma thickness through lignification.
Mapping of Candidate Genes for Nitrogen Uptake and Utilization in Japonica Rice at Seedling Stage
Authors: Chen Ning , Ma Tianze , Xia Sijia , Li Chengxin , Liu Yinuo , Wang Jiaqi , Qu Guize , Liu Hualong , Zheng Hongliang , Yang Luomiao , Zou Detang , Wang Jingguo , Xin Wei
Published: March 2024

Nitrogen (N) is one of the essential nutrients for the growth and development of crops. The adequate application of N not only increases the yield of crops but also improves the quality of agricultural products, but the excessive application of N can cause many adverse effects on ecology and the environment. In this study, genome-wide association analysis (GWAS) was performed under low- and high-N conditions based on 788,396 SNPs and phenotypic traits relevant to N uptake and utilization (N content and N accumulation). A total of 75 QTLs were obtained using GWAS, which contained 811 genes. Of 811 genes, 281 genes showed different haplotypes, and 40 genes had significant phenotypic differences among different haplotypes. Of these 40 genes, 5 differentially expressed genes (Os01g0159250, Os02g0618200, Os02g0618400, Os02g0630300, and Os06g0619000) were finally identified as the more valuable candidate genes based on the transcriptome data sequenced from Longjing31 (low-N-tolerant variety) and Songjing 10 (low-N-sensitive variety) under low- and high-N treatments. These new findings enrich the genetic resources for N uptake and utilization in rice, as well as lay a theoretical foundation for improving the efficiency of N uptake and utilization in rice.
An Identification of Functional Genetic Variants in B4GALNT2 Gene and Their Association with Growth Traits in Goats
Authors: Xu Liang , Chen Zitong , Chen Shuheng , Chen Yu , Guo Jiazhong , Zhong Tao , Wang Linjie , Zhan Siyuan , Li Li , Zhang Hongping , Cao Jiaxue
Published: March 2024

β-1,4-N-acetylgalactosamine transferase 2 (B4GALNT2) is a vital candidate gene that affects the growth traits in sheep. However, whether it has the same function in goats remains to be investigated further. This study selected 348 Nanjiang Yellow goats, screened all exons, and conserved non-coding regions of the B4GALNT2 gene for single-nucleotide polymorphisms (SNPs). Our results revealed the presence of a synonymous mutation, rs672215506, within the exon of the B4GALNT2 gene in the Nanjiang Yellow goat population. The mutation resulted in a decrease in the mRNA stability of the B4GALNT2 gene. The results of SNP detection of the conserved non-coding region of the B4GALNT2 gene showed five potential regulatory SNPs in the Nanjiang Yellow goat population. Except for rs66095343, the ~500 bp fragments of the other four SNPs (rs649127714, rs649573228, rs652899012, and rs639183528) significantly increased the luciferase activity both in goat skeletal muscle satellite cells (MuSCs) and 293T cells. The genetic diversity indexes indicated low or intermediate levels for all six SNPs analyzed, and the genotype frequencies were in Hardy–Weinberg equilibrium. Association analysis showed that rs660965343, rs649127714, and rs649573228 significantly correlate with growth traits in the later stage of growth and development of Nanjiang Yellow goats. The haplotype combinations of H2H3 and H2H2 had higher body weight and greater body size. Moreover, H2H2 haplotype combinations significantly correlated with the litter size of the Nanjiang Yellow goats. The results of our study demonstrate the potential role of the B4GALNT2 gene as a functional genetic marker in the breeding programs of Nanjiang Yellow goats.
Unmethylated Mosaic Full Mutation Males without Fragile X Syndrome
Authors: Tak YeEun , Schneider Andrea , Santos Ellery , Randol Jamie Leah , Tassone Flora , Hagerman Paul , Hagerman Randi J.
Published: March 2024

Fragile X syndrome (FXS) is the leading inherited cause of intellectual disability (ID) and single gene cause of autism. Although most patients with FXS and the full mutation (FM) have complete methylation of the fragile X messenger ribonucleoprotein 1 (FMR1) gene, some have mosaicism in methylation and/or CGG repeat size, and few have completely unmethylated FM alleles. Those with a complete lack of methylation are rare, with little literature about the cognitive and behavioral phenotypes of these individuals. A review of past literature was conducted regarding individuals with unmethylated and mosaic FMR1 FM. We report three patients with an unmethylated FM FMR1 alleles without any behavioral or cognitive deficits. This is an unusual presentation for men with FM as most patients with an unmethylated FM and no behavioral phenotypes do not receive fragile X DNA testing or a diagnosis of FXS. Our cases showed that mosaic males with unmethylated FMR1 FM alleles may lack behavioral phenotypes due to the presence of smaller alleles producing the FMR1 protein (FMRP). However, these individuals could be at a higher risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS) due to the increased expression of mRNA, similar to those who only have a premutation.
The Genetics of Tuberous Sclerosis Complex and Related mTORopathies: Current Understanding and Future Directions
Authors: Man Alice , Di Scipio Matteo , Grewal Shan , Suk Yujin , Trinari Elisabetta , Ejaz Resham , Whitney Robyn
Published: March 2024

The mechanistic target of rapamycin (mTOR) pathway serves as a master regulator of cell growth, proliferation, and survival. Upregulation of the mTOR pathway has been shown to cause malformations of cortical development, medically refractory epilepsies, and neurodevelopmental disorders, collectively described as mTORopathies. Tuberous sclerosis complex (TSC) serves as the prototypical mTORopathy. Characterized by the development of benign tumors in multiple organs, pathogenic variants in TSC1 or TSC2 disrupt the TSC protein complex, a negative regulator of the mTOR pathway. Variants in critical domains of the TSC complex, especially in the catalytic TSC2 subunit, correlate with increased disease severity. Variants in less crucial exons and non-coding regions, as well as those undetectable with conventional testing, may lead to milder phenotypes. Despite the assumption of complete penetrance, expressivity varies within families, and certain variants delay disease onset with milder neurological effects. Understanding these genotype–phenotype correlations is crucial for effective clinical management. Notably, 15% of patients have no mutation identified by conventional genetic testing, with the majority of cases postulated to be caused by somatic TSC1/TSC2 variants which present complex diagnostic challenges. Advancements in genetic testing, prenatal screening, and precision medicine hold promise for changing the diagnostic and treatment paradigm for TSC and related mTORopathies. Herein, we explore the genetic and molecular mechanisms of TSC and other mTORopathies, emphasizing contemporary genetic methods in understanding and diagnosing the condition.
A Human Homozygous HELQ Missense Variant Does Not Cause Premature Ovarian Insufficiency in a Mouse Model
Authors: Bakhshalizadeh Shabnam , Bird Anthony D. , Sreenivasan Rajini , Bell Katrina M. , Robevska Gorjana , van den Bergen Jocelyn , Asghari-Jafarabadi Mohammad , Kueh Andrew J. , Touraine Philippe , Lokchine Anna , Jaillard Sylvie , Ayers Katie L. , Wilhelm Dagmar , Sinclair Andrew H. , Tucker Elena J.
Published: March 2024

Disruption of meiosis and DNA repair genes is associated with female fertility disorders like premature ovarian insufficiency (POI). In this study, we identified a homozygous missense variant in the HELQ gene (c.596 A>C; p.Gln199Pro) through whole exome sequencing in a POI patient, a condition associated with disrupted ovarian function and female infertility. HELQ, an enzyme involved in DNA repair, plays a crucial role in repairing DNA cross-links and has been linked to germ cell maintenance, fertility, and tumour suppression in mice. To explore the potential association of the HELQ variant with POI, we used CRISPR/Cas9 to create a knock-in mouse model harbouring the equivalent of the human HELQ variant identified in the POI patient. Surprisingly, Helq knock-in mice showed no discernible phenotype, with fertility levels, histological features, and follicle development similar to wild-type mice. Despite the lack of observable effects in mice, the potential role of HELQ in human fertility, especially in the context of POI, should not be dismissed. Larger studies encompassing diverse ethnic populations and alternative functional approaches will be necessary to further examine the role of HELQ in POI. Our results underscore the potential uncertainties associated with genomic variants and the limitations of in vivo animal modelling.
FOXO3/Rab7-Mediated Lipophagy and Its Role in Zn-Induced Lipid Metabolism in Yellow Catfish (Pelteobagrus fulvidraco)
Authors: Xiao Fei , Chen Chuan , Zhang Wuxiao , Wang Jiawei , Wu Kun
Published: March 2024

Lipophagy is a selective autophagy that regulates lipid metabolism and reduces hepatic lipid deposition. However, the underlying mechanism has not been understood in fish. In this study, we used micronutrient zinc (Zn) as a regulator of autophagy and lipid metabolism and found that Ras-related protein 7 (rab7) was involved in Zn-induced lipophagy in hepatocytes of yellow catfish Pelteobagrus pelteobagrus. We then characterized the rab7 promoter and identified binding sites for a series of transcription factors, including Forkhead box O3 (FOXO3). Site mutation experiments showed that the −1358/−1369 bp FOXO3 binding site was responsible for Zn-induced transcriptional activation of rab7. Further studies showed that inhibition of rab7 significantly inhibited Zn-induced lipid degradation by lipophagy. Moreover, rab7 inhibitor also mitigated the Zn-induced increase of cpt1α and acadm expression. Our results suggested that Zn exerts its lipid-lowering effect partly through rab7-mediated lipophagy and FA β-oxidation in hepatocytes. Overall, our findings provide novel insights into the FOXO3/rab7 axis in lipophagy regulation and enhance the understanding of lipid metabolism by micronutrient Zn, which may help to reduce excessive lipid accumulation in fish.
Mesenchymal Tumors of the Gastrointestinal Tract—Beyond GIST—A Review
Authors: Gama João Martins , Oliveira Rui Caetano
Published: March 2024

Sarcomas are rare lesions and encompass a wide variety of entities, depending on their nature. In recent years new entities have been described and new knowledge, especially that provided by molecular studies, has been increasing. This makes it very difficult to be updated with all the described entities, since only some of the centers have the desired ancillary studies for the correct diagnosis. Some lesions are extremely rare and may appear once or twice during the lifetime of a general pathologist. When we refer to sarcomas of the gastrointestinal tract, the gastrointestinal stromal tumor (GIST) is the most well-known lesion that the pathologist will most frequently find in daily practice. This paper aims to comprehensively review the sarcomas associated with the gastrointestinal tract, emphasizing histopathology and going beyond GIST. This review highlights the histopathology of rare types of sarcomas so it may increase awareness of common and rare lesions, prompting an easy and effective diagnosis.