bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of ROS Production by Catechin Is a Primary Effect of Increased Azole Efficacy in Nakaseomyces glabratus (Candida glabrata) Cells Lacking the ERG6 Gene
Authors: Tóth Hervay Nora , Eliaš Daniel , Černáková Lucia , Jacko Juraj , Habová Marcela , Chovancová Natália , Gbelská Yvetta
Published: September 2024

Fungal infections have become an important public health problem. Currently, there are only three available classes of antifungals for the treatment of invasive infections. Two of them, azoles and polyenes, target the synthesis of ergosterol or bind to sterols. A promising strategy to improve current therapies is the use of natural compounds in combinational therapies with the existing antifungals. In this work, we analyzed the changes in the susceptibility of the mutant strain of Nakaseomyces glabratus (Candida glabrata) lacking the ERG6 gene (encoding the sterol C-24 methyltransferase in ergosterol biosynthesis) in the presence of catechin and antifungal azoles. The reduced content of ergosterol in the Cgerg6Δ mutant resulted in the increased tolerance of the mutant cells to both azoles and polyenes. The combination of catechin with fluconazole or miconazole led to the growth inhibition of the azole-resistant Cgerg6Δ mutant strain. In the presence of catechin and miconazole, the Cgerg6Δ mutant fails to properly activate the expression of genes encoding the transcription factors CgYap1p and CgMsn4p, as well as the gene expression of CgCTA1, which are involved in oxidative stress response and lead to the intracellular accumulation of ROS. Finally, we show that catechin administration reduces mortality in a Galleria mellonella model infected with C. glabrata. Our work thus supports the use of catechin in combination therapies for fungal infections and shows that the CgERG6 gene could be a potential new drug target.
Novel Tricyclic Flavonoids as Promising Anti-MRSA Agents
Authors: Moldovan Cristina-Veronica , Mantea Loredana-Elena , Savu Mihaela , Jones Peter G. , Sarbu Laura Gabriela , Stefan Marius , Birsa Mihail Lucian
Published: September 2024

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is considered the main cause of nosocomial and community-associated infections. Because of antimicrobial resistance, MRSA infections are difficult or impossible to treat, leading to high mortality rates and significant economic and societal costs. In view of the MRSA challenge to public health all over the world, the identification of new and effective anti-MRSA agents is a high medical priority. Objectives: A new series of tricyclic flavonoids with a methyl substituent on ring A of the flavonoid skeleton was synthesized to assess their antimicrobial properties. Methods: The structures of novel synthetic tricyclic flavonoids and their 3-dithiocarbamic flavanones were proven by X-ray structural analyses. Minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) were used to evaluate antimicrobial activity. Growth kinetic and time–kill assays were employed to confirm the antibacterial effectiveness. The mechanism of action was investigated using fluorescence microscopy. Results: Our results show that the tricyclic flavonoids exhibited important antibacterial and antifungal activities, with MIC and MBC values as low as 1.95 µg/mL and 3.90 µg/mL recorded for compound 5e against a multidrug-resistant MRSA strain. Flavonoid 5e induced a more important bacteriostatic effect compared with chloramphenicol, inhibiting the bacterial growth for up to 24 h at concentrations equivalent to 2 × MIC. Also, 5e exhibited a significant bactericidal activity, with no viable cells evidenced after 6 h of incubation in the presence of MBC and a total kill effect recorded up to 24 h. The anti-MRSA activity may be explained by the cell membrane impairment induced by 5e. Conclusions: All the data support the idea that flavonoid 5e is a reliable candidate to develop effective anti-MRSA agents, but further studies are necessary.
Comparative Pharmacokinetics of Sustained-Release versus Immediate-Release Melatonin Capsules in Fasting Healthy Adults: A Randomized, Open-Label, Cross-Over Study
Authors: Thanawala Shefali , Abiraamasundari R. , Shah Rajat
Published: September 2024

Background: Exogenous melatonin, a nutraceutical for maintaining a healthy sleep–wake cycle and managing sleep disorders, requires large, repeated doses due to its low bioavailability and short half-life. This necessitates the development of a sustained-release formulation with a longer half-life and sustained plasma concentration. Therefore, exogenous novel 5 mg sustained-release melatonin capsules (Melatonin-SR, test product) were formulated. Methods: This open-label cross-over study compared the pharmacokinetics (maximum concentration [Cmax], time to reach Cmax [Tmax], area under the curve [AUC], and elimination half-life [t1/2]) and the safety of Melatonin-SR with 5 mg immediate-release melatonin capsules (Melatonin-IR, reference product) after single-dose oral administration in healthy fasting adults. Results: Sixteen participants (aged 18–45 years) were randomized (1:1) to receive either Melatonin-SR or Melatonin-IR in two periods with a 7-day washout period. Melatonin-SR reported a lower Cmax (11,446.87 pg/mL) compared to Melatonin-IR (22,786.30 pg/mL). The mean Tmax of Melatonin-SR and Melatonin-IR was 1.26 h and 0.87 h, respectively. The mean t1/2 of Melatonin-SR (5.10 h) was prolonged by five-fold compared to Melatonin-IR (1.01 h). One adverse event (vomiting) was reported following the administration of the Melatonin-IR. Conclusions: Melatonin-SR resulted in higher and sustained plasma melatonin concentrations for an extended period and was well-tolerated. Hence, Melatonin-SR may be a promising nutraceutical for maintaining healthy sleep.
SBS Mitigation by Manipulating the Injecting Polarization Direction in a High-Power Monolithic PM Amplifier
Authors: Wen Yu , Zhang Chun , Liu Chenxu , Chu Qiuhui , Huang Lingli , Zhu Yuan , Zhang Haoyu , Tao Rumao , Lin Honghuan , Wang Jianjun
Published: September 2024

The polarization direction-dependent SBS threshold was investigated, and the terminal polarization control technique was demonstrated to restore the linear polarization state. By increasing the relative angle of the injecting polarization direction from 0° to 90°, the measured SBS threshold increased until reaching a maximum value, beyond which it decreased in a nearly symmetrical trend. The highest SBS threshold was achieved with the relative polarization angle being 45°, delivering a 67% threshold enhancement compared with that at 0°. A quarter-wave-plate was used to restore the polarization state of the output laser manually from an elliptic to a linearly polarized state, and temperature-dependent polarization fluctuation was observed, which intensified as the laser power was scaled. By reducing the cooling temperature, a 1 kW laser with a linearly polarized state was demonstrated using a 45° polarization direction-injected monolithic PM amplifier.
Development of Miniaturised Fibre-Optic Laser Doppler Velocimetry for Opaque Liquid: Measurement of the Velocity Profile in the Engine Oil Flow of a Lubrication System
Authors: Tajikawa Tsutomu , Kohri Shimpei , Mouri Taiki , Fujimi Takaichi , Yamaguchi Hiromasa , Ohba Kenkichi
Published: September 2024

This study developed a fibre-optic laser Doppler velocimetry sensor for use in opaque, high-temperature, and high-pressure fluid flows by inserting the fibre perpendicular to the main flow. The tip of the optical fibre was obliquely polished and chemically etched using a buffered hydrofluoric acid solution, and a reflective mirror was deposited on the surface of the oblique fibre tip. Based on the results of the verification test using the rotating annular open channel, the fabrication conditions of the fibre tip were optimized for measuring the lubricating oil flow. The flow velocity profiles in the engine’s oil flow of the lubrication system during engine bench testing were measured. These velocity profiles were influenced by variations in the measurement position, oil temperature, and engine speed. The measurement accuracy of this sensor was compared with the volumetric flow rate obtained by cross-sectional area integration of the flow velocity profile, as measured using a Coriolis flowmeter, and the difference was within 1%. By combining computational simulation for flow and optical attenuation and particle scattering in light transmission through a working fluid, this fibre-optic sensor achieved a measurement volume of 200 microns in length and 200 microns in width at a distance of 900–1000 microns from the sensor.
Attenuation Characteristics of a 905-nm Pulsed Laser for Short-Range Transmission in Snowfall Environments
Authors: Chen Miaomiao , Gan Lin , Zhang He , Ke Changkun
Published: September 2024

Aiming at the problems of power attenuation and spot expansion of pulsed laser transmission in snowfall environments, based on ray scattering and Fraunhofer diffraction theories, a model of laser transmission attenuation in snowfall environments is established. The model considers the influence of multiple scattering effects by introducing a forward correction coefficient. The Monte Carlo multiple scattering model was used to numerically simulate the attenuation characteristics of a 905-nm pulsed laser in snowfall environments, and an experimental platform for the attenuation characteristics was constructed. The experimental, simulation, and theoretical results show that, in three snowfall environments of 0 < SR < 1, 1 < SR < 2, and 2 < SR < 3, the laser transmittance decreases with the increase of transmission distance, and when the transmission distance is the same, the laser transmittance decreases with the increase in snowfall rate. The influence of transmission distance, simulated photon number, and asymmetry factor on spot extension was studied. The simulation results show that the spot radius increases with the increase in transmission distance, remains almost constant with the increase in the simulated photon number, and decreases with the increase in the asymmetry factor in three snowfall environments.
Growth of Low-Temperature Epitaxial Lithium Niobate Thin Films and Guided-Wave Optical Properties
Authors: Bui Thanh Ngoc Kim , Wagner Estelle , Moalla Rahma , Maudez William , Dogheche Karim , Bachelet Romain , Masenelli Bruno , Benvenuti Giacomo , Rémiens Denis , Dogheche El Hadj
Published: September 2024

LiNbO3 thin films are grown on a c-plane (0001) sapphire wafer at a relatively low substrate temperature by chemical beam vapor deposition (CBVD) in Sybilla equipment. Raman measurements only evidence the LiNbO3 phase, while HR-XRD diffractograms demonstrate a c-axis-oriented growth with only (006) and (0012) planes measured. The rocking curve is symmetric, with a full width at half maximum (FWHM) of 0.04°. The morphology and topography observed by SEM and AFM show very low roughness, with rms equaling 2.0 nm. The optical properties are investigated by a guided-wave technique using prism coupling. The ordinary refractive index (no) and extraordinary refractive index (ne) at different wavelengths totally match with the LiNbO3 bulk, showing the high microstructural quality of the film. The film composition is estimated by Raman and bi-refringence and shows a congruent or near-stoichiometric LiNbO3.
Real-Time Simulation of Clear Sky Background Radiation in Gas Infrared Remote Sensing Monitoring
Authors: Shu Shengquan , Liu Jianguo , Xu Liang , Wang Yuhao , Deng Yasong , Sun Yongfeng
Published: September 2024

During the process of infrared remote sensing monitoring, obtaining real-time measurements of sky background radiation is extremely inconvenient. The current methods incur a certain amount of lag. In this study, within the existing theoretical framework, a fast transmittance calculation method using interpolation was adopted, and a simplified transmission model was established. This led to the development of a new and simplified method for rapid temperature and humidity retrieval. Compared to the line-by-line integration method, the interpolation method significantly improves the speed of transmittance calculation by several tens of times, while maintaining a high level of accuracy. The relative deviation between the results obtained using the interpolation method and those obtained through line-by-line integration is less than 1 ‱. With the proposed method, temperature and humidity profile information can be retrieved from measured spectra within 5 min and corresponding background spectra can be obtained. The differences between the calculated background radiation and the measured spectra using the new method are smaller, making it more suitable for calculating sky background radiation. Additionally, the rapid retrieval results of the temperature profiles in the lower atmosphere have a certain level of accuracy (the mean deviation is less than 2 K).
RNA-Seq Analysis and Candidate Gene Mining of Gossypium hirsutum Stressed by Verticillium dahliae Cultured at Different Temperatures
Authors: Yang Ni , Gong Zhaolong , Liang Yajun , Geng Shiwei , Sun Fenglei , Li Xueyuan , Qian Shuaishuai , Lai Chengxia , Yusuyin Mayila , Wang Junduo , Zheng Juyun
Published: September 2024

The occurrence and spread of Verticillium dahliae (V. dahliae) in cotton depends on the combined effects of pathogens, host plants, and the environment, among which temperature is one of the most important environmental factors. Studying how temperature impacts the occurrence of V. dahliae in cotton and the mechanisms governing host defense responses is crucial for disease prevention and control. Understanding the dual effects of temperature on both pathogens and hosts can provide valuable insights for developing effective strategies to manage this destructive fungal infection in cotton. This study was based on the deciduous V. dahliae Vd-3. Through cultivation at different temperatures, Vd-3 formed the most microsclerotia and had the largest colony diameter at 25 °C. Endospore toxins were extracted, and 48 h was determined to be the best pathogenic time point for endotoxins to infect cotton leaves through a chlorophyll fluorescence imaging system and phenotypic evaluation. Transcriptome sequencing was performed on cotton leaves infected with Vd-3 endotoxins for 48 h at different culture temperatures. A total of 34,955 differentially expressed genes (DEGs) were identified between each temperature and CK (no pathogen inoculation), including 17,422 common DEGs. The results of the enrichment analysis revealed that all the DEGs were involved mainly in photosynthesis and sugar metabolism. Among the 34,955 DEGs, genes in the biosynthesis and signal transduction pathways of jasmonic acid (JA), salicylic acid (SA), and ethylene (ET) were identified, and their expression patterns were determined. A total of 5652 unique DEGs were clustered into six clusters using the k-means clustering algorithm, and the functions and main transcription factors (TFs) of each cluster were subsequently annotated. In addition, we constructed a gene regulatory network via weighted correlation network analysis (WGCNA) and identified twelve key genes related to cotton defense against V. dahliae at different temperatures, including four genes encoding transcription factors. These findings provide a theoretical foundation for investigating temperature regulation in V. dahliae infecting cotton and introduce novel genetic resources for enhancing resistance to this disease in cotton plants.
Enhancing Red Table Grape Coloration Using Tsikoudia: A Novel and Sustainable Approach
Authors: Kontaxakis Emmanouil , Lydakis Dimitrios , Fisarakis Ioannis
Published: September 2024

Achieving optimal coloration in red table grapes, especially in warm-climate regions, presents significant challenges due to high temperatures that inhibit anthocyanin biosynthesis. Conventional methods to enhance grape coloration, including the use of abscisic acid (ABA), ethephon, foliar nutrient supplementation, and viticultural practices like cluster trimming and girdling, have limitations related to cost, regulatory restrictions, and potential adverse effects on grapes quality. This study proposes the application of tsikoudia, a traditional Greek alcoholic beverage, as a novel, sustainable, and cost-effective alternative to conventional practices. Tsikoudia, applied during the veraison stage, significantly improved the coloration of ‘Crimson Seedless’ and ‘Red Globe’ grapes by enhancing anthocyanin accumulation and altering color parameters. Specifically, lightness (L*), chroma (C*), and hue angle (h), measured using the CIE-Lab color system, were reduced, while the Color Index for Red Grapes (CIRG) was increased. Additionally, total anthocyanin content, determined through spectrophotometric analysis, also showed an increase. These changes indicate a more intense red coloration. This research highlights the effectiveness of tsikoudia in improving grape coloration and contributes to the development of more sustainable viticultural practices.
Genome-Wide Identification of the COMT Gene Family in Juglans regia L. and Response to Drought Stress
Authors: Ma Xiaolan , Luo Hongjia , Li Jianhong , Wei Zhiyue , Gao Yanlong , Zhang Zhongxing , Wang Yanxiu
Published: September 2024

Caffeic acid O-methyltransferase (COMT), as a multifunctional enzyme involved in various physiological and biochemical processes in lignin metabolism, plays an important role in a plant’s response to stress. In this study, we isolated COMT family members from the walnut genome by bioinformatics and analyzed their physicochemical properties and their expression under drought stress to provide gene resources for drought resistance in walnut. The results showed that 33 COMT genes were identified from walnuts and distributed on different chromosomes. The molecular weight of proteins varies greatly. According to the phylogenetic tree, the family can be divided into seven subgroups, which are relatively conservative in evolution and closely related to Arabidopsis thaliana. Promoter analysis showed that the promoter of the walnut COMT gene contains rich cis-elements of plant hormone response and stress response, and the real-time fluorescence scale name can be significantly induced by drought stress. Compared with wild-type Arabidopsis, overexpression JrCOMT19 significantly increased the enzyme activity (SOD, POD, and CAT) and proline content. Meanwhile, overexpression of JrCOMT19 significantly increased the lignin content and expression of related genes. Therefore, JrCOMT plays an important role in responding to drought in walnuts, and overexpression JrCOMT19 can improve the resistance to drought stress by increasing lignin content, antioxidant enzyme activity, and osmotic substance content.
Performance Enhancement of Polyurethane Acrylate Resin by Urushiol: Rheological and Kinetic Studies
Authors: Zhang Yuchi , Fang Run , Xue Hanyu , Ye Yuansong , Chen Li , Xia Jianrong
Published: September 2024

A natural extract, i.e., urushiol, was employed to effectively cross-link and modify commercial wet-cured polyurethane acrylic resin. Comprehensive characterization of the paint film was performed using techniques such as FTIR, SEM, and TGA. The results indicated that the incorporation of urushiol significantly increased the cross-linking density of the resin, which in turn enhanced the film-forming properties, mechanical strength, and thermal stability of the paint film. Additionally, the study discovered that under isothermal conditions, the dynamic moduli (G′ and G″) of the paint film are related to the gel point frequency by a power law, aligning with the predictions of percolation theory. The application of the autocatalytic model has provided a novel approach to studying non-isothermal kinetic reactions, offering valuable insights for process optimization and further development of urushiol-based polyurethane.
Recent Advances in Propylene-Based Elastomers Polymerized by Homogeneous Catalysts
Authors: Li Chengkai , Fan Guoqiang , Zheng Gang , Gao Rong , Liu Li
Published: September 2024

Propylene-based elastomers (PBEs) have received widespread attention and research in recent years due to their structural diversity and excellent properties, and are also an important area for leading chemical companies to compete for layout, but efficient synthesis of PBEs remains challenging. In this paper, we review the development of PBEs and categorize them into three types, grounded in their unique chain structures, including homopolymer propylene-based elastomers (hPBEs), random copolymer propylene-based elastomers (rPBEs), and block copolymer propylene-based elastomers (bPBEs). The successful synthesis of these diverse PBEs is largely credited to the relentless innovative advancements in homogeneous catalysts (metallocene catalysts, constrained geometry catalysts, and non-metallocene catalysts). Consequently, we summarize the catalytic performance of various homogeneous catalysts employed in PBE synthesis and delve into their effect on molecular weight, molecular weight distribution, and chain structures of the resulting PBEs. In the end, based on the current academic research and industrialization status of PBEs, an outlook on potential future research directions for PBEs is provided.
Influence of the Molecular Weight of the Polycarbonate Polyol on the Intrinsic Self-Healing at 20 °C of Polyurethanes
Authors: Paez-Amieva Yuliet , Martín-Martínez José Miguel
Published: September 2024

Different polyurethanes (PUs) were synthesized with polycarbonate polyols of molecular weights of 500, 1000, and 2000 Da. Their self-healing abilities at 20 °C were tested, and their structural, thermal, and mechanical properties were analyzed. The PUs made with polycarbonates of molecular weights 500 (YC500) and 1000 Da (YC1000) exhibited self-healing at 20 °C, and the self-healing time of YC1000 was the shortest. The absence of crystallinity and the low degree of micro-phase separation favored self-healing at 20 °C in YC500. However, the presence of tack and the existence of allophanate species and urethane–carbonate and urea–carbonate hydrogen bonds disfavored self-healing. Consequently, the self-healing time at 20 °C of YC500 was longer than expected. On the other hand, YC1000 exhibited an “equilibrium” between urethane-carbonate and urea–carbonate hydrogen bonds and carbonate–carbonate interactions among the soft segments, so a particular structural order was produced that was associated with its fastest self-healing at 20 °C. The PU made with the polycarbonate of molecular weight 2000 Da did not exhibit self-healing at 20 °C because of its significant micro-phase separation, the presence of semi-crystalline soft domains, and the lower density of hydrogen bonds.
Effect of CO2 Concentration on the Performance of Polymer-Enhanced Foam at the Steam Front
Authors: Wu Mingxuan , Li Binfei , Ruan Liwei , Zhang Chao , Tang Yongqiang , Li Zhaomin
Published: September 2024

This study examines the impact of CO2 concentration on the stability and plugging performance of polymer-enhanced foam (PEF) under high-temperature and high-pressure conditions representative of the steam front in heavy oil reservoirs. Bulk foam experiments were conducted to analyze the foam performance, interfacial properties, and rheological behavior of CHSB surfactant and Z364 polymer in different CO2 and N2 gas environments. Additionally, core flooding experiments were performed to investigate the plugging performance of PEF in porous media and the factors influencing it. The results indicate that a reduction in CO2 concentration in the foam, due to the lower solubility of N2 in water and the reduced permeability of the liquid film, enhances foam stability and flow resistance in porous media. The addition of polymers was found to significantly improve the stability of the liquid film and the flow viscosity of the foam, particularly under high-temperature conditions, effectively mitigating the foam strength degradation caused by CO2 dissolution. However, at 200 °C, a notable decrease in foam stability and a sharp reduction in the resistance factor were observed. Overall, the study elucidates the effects of gas type, temperature, and polymer concentration on the flow and plugging performance of PEF in porous media, providing reference for fluid mobility control at the steam front in heavy oil recovery.
Morphological, Thermal, and Mechanical Assessment of Polypropylene and Ammonium Phosphate Composites Enhanced with Lignosulfonate and Zirconium
Authors: Tosin Keiti Gilioli , Aguzzoli Cesar , Poletto Matheus
Published: September 2024

Polypropylene and ammonium phosphate (AP) composites were synthesized at a 25 wt% concentration. The changes in the morphological, thermal, and physical behavior of the composites were analyzed with the addition of lignosulfonate (LG) and zirconium phosphate (ZrP). Additionally, metallic zirconium was deposited onto lignosulfonate using the magnetron sputtering technique to develop polypropylene and zirconium-modified lignosulfonate (LGMod) composites. Thus, composites of PP/25AP, PP/25AP/8LG/5ZrP, and PP/25AP/8LGMod were synthesized. The synthesis involved mixing the materials in a Hake mixer, followed by compression molding. The composites were characterized by field emission scanning electron microscopy (SEM–EDS), a thermogravimetric analysis (TGA) with combustion parameters, a vertical burn test (UL-94), a thermal camera, and mechanical properties. All composites achieved a V2 rating according to UL-94 standards. The PP/25AP extinguishes flames more quickly compared to other materials, approximately 99.2% faster than PP and showed the lowest temperature variation and mass loss after burning. The PP/25AP/8LG/5ZrP composite exhibited a 7% higher rigidity and 84.5% better flame retardancy compared to pure PP. Additionally, substituting ZrP with LGMod led to a lower environmental impact and improved thermal properties, despite some mechanical disadvantages.
Evaluation of Bond Strength of Concrete Repaired Using Polyurethane Grout Material under Static and Impact Loads Coupled with Statistical Analysis
Authors: Haruna Sadi Ibrahim , Ibrahim Yasser E. , Al-shawafi Ali
Published: September 2024

The effectiveness of repair work relies on whether the interface substrate can achieve sufficient bond strength when subjected to numerous stresses. This study investigated the bond properties of repaired normal concrete (NC-to-NC) elements, including cube, beam, and U-shaped specimens, after undergoing natural fracture due to flexural and tensile stresses. The specimens were repaired using a polyurethane (PU) matrix by gluing the two parts and applying compression, splitting, and drop-weight impact (DWI) tests to evaluate the bond strength properties. The results revealed that the PU matrix effectively repairs NC substrate with adequate bond strength, which exceeds the minimum allowable bond strength specified in the ASTM ACI 546-06 to rehabilitate damage concrete structures. The reference beams exhibit a peak applied load capacity of 15.6 kN with less deflection than the repaired samples. The compressive strength of the NC-to-NC repaired specimens loaded along and parallel to the interface plane revealed a decrease in compressive strength of 47.3% and 31.5% compared to the NC-R samples, respectively. The mean number of blows at the cracking stages appeared nearly equal for reference and repaired NC-to-NC specimens. The reference specimens exhibited an average number of 24 and 31 blows at the initial and failure stages, respectively, which were higher by 9.1% and 5.2% than the NC-to-NC repaired specimens. The PU binder showed promising results in achieving adequate interfacial bond strength under static and impact loads.
Optimization of the Industrial Production Process of Tunisian Date Paste for Sustainable Food Systems
Authors: Ben Amara Sana , Lakoud Atef , Mahmoudi Imen , Ben Tekaya Imene , Amri Assila , Snoussi Ahmed , Hachani Mondher , Fattouch Sami , Hassouna Mnasser
Published: September 2024

The production of date paste from second-grade date fruits is a fast-growing industrial activity which promotes more sustainable food systems. The industrial date paste process is mainly dependent on the thermal treatments of hydration and drying that precede flesh crushing. These thermal treatments are commonly performed industrially using steam hydration instead of water soaking and convective hot air drying, which are known to be energy-intensive operations leading to high greenhouse gas emissions. The objective of this work was to optimize, on the one hand, the operations of hydration and drying of dates at an industrial scale using a response surface Box–Behnken experimental design in order to reduce the energy consumption and, on the other hand, to assess the biochemical and microstructural properties of date paste produced under optimized conditions. Optimization was performed based on the measurements of sensory attributes, instrumental texture firmness, moisture content, water activity (aw), and color parameters (L*, a*, b*), as well as on the energy savings related to the factors of hydration duration and temperature and time of drying. The optimal conditions to ensure the highest quality of the final product and the lowest energy consumption were 9.6 min of hydration at 80 °C and 3 h of drying at 52.28 °C. The biochemical analysis of the date paste produced under the optimized process showed that it is rich in dietary fibers (9.80 ± 2.10%) and total phenols (261 ± 6.2 mg gallic acid equivalent/100 g of extract). Furthermore, the studied sample exhibited a higher antioxidant potential than the raw date material as a result of the heat-inhibitory effect of oxidases. The obtained results suggest that date paste presents a good source of natural bioactive molecules and could potentially be considered as a functional food ingredient. SEM analysis showed that the microstructural properties of date paste produced under optimal conditions may promote its quality preservation during storage.
A Numerical Investigation on Kick Control with the Displacement Kill Method during a Well Test in a Deep-Water Gas Reservoir: A Case Study
Authors: Li Qingchao , Li Qiang , Han Ying
Published: September 2024

The efficient exploitation of marine oil and gas resources holds significant potential to mitigate the current severe energy crisis. Regrettably, incidents, such as gas kick and even blowouts, can significantly impact normal development activities. The displacement kill method is one effective strategy for well control in deep-water areas. In this study, the detailed mathematical method for determining kill parameters involved in the kill operation by using the displacement kill method was proposed. Of course, this includes both cases: one where the kill fluid leaks during the kill process and another where no leakage occurs. Meanwhile, its applicability was verified through comparison with experimental results. Then, evolution characteristics of kill parameters, when killing fluid leakage occurs and when it does not occur, were analyzed. Finally, factors, such as pit gain and shut-in casing pressure, affecting the kill parameters of kill operation, were explored. It was found that the experimental and calculated results show great similarity, although there are slight differences between them. The total kill time in the simulation is 44 s shorter than that in the verification experiment. This indicates that the model established in this study is suitable for simulating the process of kill operation using the displacement kill method. In addition, the investigation results show that leakage of kill fluid increases the difficulty of the kill operation and prolongs the operation time. The number of kill cycles in the presence of kill fluid leakage is one more than that when there is no fluid leakage, resulting in an additional 70 min of total duration. Furthermore, the increase in pit gain and the rise in shut-in casing pressure can also pose challenges to the kill operations. The total kill time will be extended by 164 min when the mud pit gain increases from 20 m3 to 50 m3. The number of kill cycles rises by two when the shut-in casing pressure is increased from 5 MPa to 20 MPa. To ensure the safety of the drilling operation in abnormally high-pressure reservoirs, it is crucial to monitor parameters such as casing pressure during the drilling process and timely well control measures.
Feasibility Verification of Casing Drilling in Shallow Marine Formations
Authors: Song Gang , Zhang Xin , Chen Xiaojun , Cui Shuying , Niu Qinglei , Tian Yingying , Ning Bo , Jiang Yuanzhuang , Zhao Ming , Chen Genlong , Han Zelong , Ren Qiwei , Jiang Yafeng
Published: September 2024

DDWC (Directional Drilling with Casing) is an effective wellbore construction technique, particularly suitable for soft marine formations. In DDWC, the casing replaces the drill pipe for sliding drilling operations, and the passability of the drill string through the casing has become one of the primary challenges in applying DDWC. This study uses ANSYS Workbench to simulate the strain and bending behavior of the casing under various geological conditions. Simulations were conducted for different wellbore trajectories, casing specifications, and materials to evaluate the feasibility of the drill string passing through the casing under different conditions. The results show that, when the dogleg severity reaches 18°/30 m and the casing’s inner diameter is 315 mm, the maximum radial strain of the casing is 4.2 mm, which cannot guarantee the successful passage of a drill string assembly with a 311 mm outer diameter. For other casing specifications, with a minimum inner diameter of 317 mm, the drill string can pass through under the maximum dogleg severity. Additionally, since the elastic modulus and Poisson’s ratio of the casing materials are identical, the strain behavior is consistent across different materials, meaning that the material does not affect the passability of the casing. Moreover, the study optimized the selection of casing specifications and materials. From the perspective of ensuring drill string passability and resource conservation, a casing with an inner diameter of 319.4 mm was chosen. To ensure the longevity of the casing and the stability of the wellbore, N80 steel was selected as the material. A sensitivity analysis was conducted on the factors affecting casing strain, and the results aligned with the simulation findings, showing that wellbore trajectory and casing specifications have a significant impact on casing strain. Verifying the passability of the drill string through the casing is critical for the development and application of DDWC technology.
Removal of Cd2+ and Pb2+ from an Aqueous Solution Using Modified Coal Gangue: Characterization, Performance, and Mechanisms
Authors: Chang Zhibing , Lu Chunwei , Bai Lu , Guo Nan , Xing Zhenguo , Yan Yinuo
Published: September 2024

The impact of various modification methods on enhancing the adsorption performance of coal gangue (CG) for hazardous heavy metals has not been thoroughly investigated. In this study, three CG samples were first modified by calcination, followed by acid washing, alkali washing, and hydrothermal treatment, to obtain modified CG samples. The adsorption performance was assessed based on the adsorption capacities for Cd2⁺ and Pb2⁺ (i.e., qe,Cd and qe,Pb), and the kinetics of the adsorption processes were analyzed using kinetic equations. XRD, SEM-EDX, FTIR, and N2 adsorption–desorption isotherms were used to elucidate the adsorption mechanisms. Results indicated that qe,Cd and qe,Pb of raw CG samples were approximately 10 and 25 mg/g, respectively, with only slight changes observed after calcination, acid washing, and alkali washing. In contrast, hydrothermal treatment yielded NaP and NaA zeolites, which significantly enhanced qe,Cd and qe,Pb to values of 48.5–72.7 and 214.9–247.5 mg/g, respectively. The hydrothermally treated CG samples primarily adsorbed Cd2⁺ and Pb2⁺ through ion exchange with Na⁺ within the zeolite structure, facilitating the entry of these ions into the zeolite’s pore channels. The adsorption processes were effectively described by the pseudo-second-order kinetic model. By optimizing the conditions of hydrothermal modification, the adsorption performance of CG samples is anticipated to further improve due to the creation of additional adsorption sites.
A Comparative Study of Drying Technologies for Apple and Ginger Pomace: Kinetic Modeling and Antioxidant Properties
Authors: Araujo Beatriz Z. R. , Martins Valter F. R. , Pintado Manuela E. , Morais Rui M. S. C. , Morais Alcina M. M. B.
Published: September 2024

Apple and ginger mixed pomace is a by-product that can be valorized by drying. In this study, mixed pomace was subjected to hot-air drying (HAD) at 45, 62, and 70 °C and stepwise at 45 °C followed by at 62 °C or the reverse, at 62 °C followed by at 45 °C (2.5 mm layer), and microwave drying (MWD) at 100, 180, and 300 W (2.5 mm and 1.5 mm layers) and stepwise at 100 W followed by at 300 W (2.5 mm layer). The results show that the Crank model well fitted the HAD kinetics, with a water effective diffusivity (Deff) of 2.28 ± 0.06 × 10−10–4.83 ± 0.16 × 10−10 m2/s and energy of activation of 23.9 kJ/mol. The step approach of drying at 45 °C followed by at 62 °C resulted in a higher Deff than the reverse approach (drying at 62 °C followed by at 45 °C). The Midilli et al. model presented a good fit for the MWD kinetics. The drying time was calculated using these models to achieve 12% moisture content in the pomace and found to be 125.0 ± 9.2–439.5 ± 118.2 min for HAD, and 11.1 ± 0.2–61.5 ± 6.0 min for MWD. The specific energy required was 410.78 ± 6.30–763.79 ± 205.4 kWh/kg and 1.32 ± 0.01–2.26 ± 0.05 kWh/kg, respectively. MWD at 180 W preserved the total phenolic content and the antioxidant activity (ABTS, DPPH) better than HAD at 62 °C. The former technology also preserved the pomace color well, with a low color difference, ΔE, of 7.39 ± 1.1. Therefore, MWD is more promising than HAD to dry apple and ginger pomace, reducing the environmental impact of the drying process due to its lower energy consumption, shorter drying time, and better quality. The dried product could be converted into apple and ginger pomace flour to be used as a novel food ingredient.
Synthesis of Nanostructured Mg2Ni for Hydrogen Storage by Mechanical Alloying via High-Pressure Torsion
Authors: López Gómez Edgar Ignacio , Gonzalez Joaquín , Cubero-Sesin Jorge M. , Huot Jacques
Published: September 2024

Mg2Ni is a highly promising candidate for solid-state hydrogen storage due to its high storage capacity. However, its synthesis is challenging due to the high melting point of Ni (1455 °C) and the boiling point of Mg (1090 °C). In this study, elemental powder mixtures of Mg and 30 at% Ni were processed by high-pressure torsion (HPT) to synthesize the Mg2Ni intermetallic compound through mechanical methods. The formation of 11 wt% of Mg2Ni after 50 turns of HPT was confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS), reaching a maximum of 59 wt% after 100 turns. Rietveld refinement confirmed a nanocrystalline size for the Mg2Ni phase synthesized via HPT. Hydrogenation tests showed that the Mg-Ni synthesized by HPT can absorb hydrogen at 350 °C even after several weeks of air exposure. Furthermore, a maximum absorption capacity of 3.8 wt% was reached after 20 h of hydrogen exposure for the sample with 100 turns. This capacity is close to the theoretical capacity of 3.9 wt% for this composition. The results confirm that combining HPT with subsequent heat treatment is an efficient strategy to increase the Mg2Ni fraction after HPT processing.
Detection of Wet Snow by Weakly Supervised Deep Learning Change Detection Algorithm with Sentinel-1 Data
Authors: Gong Hanying , Yu Zehao , Zhang Shiqiang , Zhou Gang
Published: September 2024

The snowmelt process plays a crucial role in hydrological forecasting, climate change, disaster management, and other related fields. Accurate detection of wet snow distribution and its changes is essential for understanding and modeling the snow melting process. To address the limitations of conventional fixed-threshold methods, which suffer from poor adaptability and significant interference from scattering noise, we propose a weakly supervised deep learning change detection algorithm with Sentinel-1 multi-temporal data. This algorithm incorporates the Multi-Region Convolution Module (MRC) to enhance the central region while effectively suppressing edge noise. Furthermore, it integrates the ResNet residual network to capture deeper image features, facilitating wet snow identification through feature fusion. Various combinations of differential images, polarization data, elevation, and slope information during and after snowmelt were input into the model and tested. The results suggest that the combination of differential images, VV polarization data, and slope information has greater advantages in wet snow extraction. Comparisons between our method, the fixed-threshold method, OTSU algorithm, and FCM algorithm against the results of Landsat images indicates that the overall accuracy of our method improves significantly when the proportion of wet snow cover is large, and the average overall accuracy of wet snow extraction is 85.2%. This study provides clues for the accurate identification of wet snow during the mid-snowmelt phase.
Spatial–Temporal Assessment of Eco-Environment Quality with a New Comprehensive Remote Sensing Ecological Index (CRSEI) Based on Quaternion Copula Function
Authors: Wang Zongmin , Hou Longfei , Yang Haibo , Zhao Yong , Chen Fei , Li Qizhao , Duan Zheng
Published: September 2024

The traditional remote sensing ecological index (RSEI), based on principal component analysis (PCA) to integrate four evaluation indexes: greenness (NDVI), humidity (WET), dryness (NDBSI), and heat (LST), is insufficient to comprehensively consider the influence of each eco-environment evaluation index on eco-environment quality (EEQ). In this research, a new comprehensive remote sensing ecological index (CRSEI) based on the quaternion Copula function is proposed to comprehensively characterize EEQ responded by integrating four eco-environment evaluation indexes. Additionally, the spatiotemporal variation of EEQ in Henan Province is evaluated using monthly CRSEI data from 2001 to 2020. The results show that: (1) The applicability and monitoring accuracy of CRSEI are better than that of RSEI, which can be used to assess the EEQ. (2) The EEQ of Henan Province declined between 2001 and 2010 but significantly improved and rebounded from 2011 to 2020. During this period, CRSEI values were higher in West and South Henan and lowest in central Henan, with West Henan consistently showing the highest values across all seasons. (3) The EEQ in Henan Province exhibited a tendency of deterioration from the central cities outward, followed by improvement from the outer areas back towards the central cities. In 2010, regions with poor EEQ made up 68.3% of the total area, whereas by 2020, regions with excellent EEQ accounted for 74% of the total area. (4) The EEQ was significantly negatively correlated with human activities, while it was positively correlated with precipitation. The research provides a reference and guidance for the scientific assessment of the regional eco-environment.
An Evaluation of Future Climate Change Impacts on Key Elements of the Water–Carbon Cycle Using a Physics-Based Ecohydrological Model in Sanchuan River Basin, Loess Plateau
Authors: Yuan Yujie , Zhu Xueping , Gao Xuerui , Zhao Xuehua
Published: September 2024

The cycle of carbon and water in ecosystems is likely to be significantly impacted by future climate change, especially in semiarid regions. While a considerable number of investigations have scrutinized the repercussions of impending climatic transformations on either the carbon or water cycles, there is a scarcity of studies delving into the effects of future climate change on the coupled water–carbon process and its interrelationships. Based on this, the Sanchuan River Basin, an ecologically fragile region of the Loess Plateau, was chosen as the research area. General circulation model-projected climate scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5) and an ecohydrological model were integrated to predict (2021–2100) changes in actual evapotranspiration (ET), surface runoff (Rs), net primary productivity (NPP), and soil organic carbon (SOC). The results indicated that under the impacts of future climatic warming and humidification, ET, Rs, and NPP will increase by 0.17–6.88%, 1.08–42.04%, and 2.18–10.14%, respectively, while SOC will decrease by 3.38–10.39% in the basin. A path analysis showed that precipitation and temperature had significant effects on ET and NPP, Rs was more sensitive to precipitation, and temperature had a significant impact on SOC. Furthermore, all climate scenarios had an average ET-NPP correlation coefficient greater than 0.6, showing that the basin’s water–carbon cycle was tightly coupled. However, under SSP5-8.5, the correlation coefficient of Rs-NPP decreased from −0.35 in the near-future period to −0.44 in the far-future period, which may indicate that the positive effect of increased precipitation on Rs-NPP would barely offset the negative effect of large future temperature increases. As a foundation for achieving sustainable water resource management and ecosystem preservation policies, this study can be utilized to build adaptation methods to manage climate change.
Evaluation of Reanalysis and Satellite Products against Ground-Based Observations in a Desert Environment
Authors: Nelli Narendra , Francis Diana , Alkatheeri Abdulrahman , Fonseca Ricardo
Published: September 2024

The Arabian Peninsula (AP) is notable for its unique meteorological and climatic patterns and plays a pivotal role in understanding regional climate dynamics and dust emissions. The scarcity of ground-based observations makes atmospheric data essential, rendering reanalysis and satellite products invaluable for understanding weather patterns and climate variability. However, the accuracy of these products in the AP’s desert environment has not been extensively evaluated. This study undertakes the first comprehensive validation of reanalysis products—the European Centre for Medium-Range Weather Forecasts’ European Reanalysis version 5 (ERA5) and ERA5 Land (ERA5L), along with Clouds and Earth’s Radiant Energy System (CERES) radiation fluxes—against measurements from the Liwa desert in the UAE. The data, collected during the Wind-blown Sand Experiment (WISE)–UAE field experiment from July 2022 to December 2023, includes air temperature and relative humidity at 2 m, 10 m wind speed, surface pressure, skin temperature, and net radiation fluxes. Our analysis reveals a strong agreement between ERA5/ERA5L and the observed diurnal T2m cycle, despite a warm night bias and cold day bias with a magnitude within 2 K. The wind speed analysis uncovered a bimodal distribution attributed to sea-breeze circulation and the nocturnal low-level jet, with the reanalysis overestimating the nighttime wind speeds by 2 m s−1. This is linked to biases in nighttime temperatures arising from an inaccurate representation of nocturnal boundary layer processes. The daytime cold bias contrasts with the excessive net radiation flux at the surface by about 50–100 W m−2, underscoring the challenges in the physical representation of land–atmosphere interactions.