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Keywords = permeability index

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21 pages, 14626 KiB  
Article
Hydrogeochemical Insights into the Sustainable Prospects of Groundwater Resources in an Alpine Irrigation Area on Tibetan Plateau
by Shaokang Yang, Zhen Zhao, Shengbin Wang, Shanhu Xiao, Yong Xiao, Jie Wang, Jianhui Wang, Youjin Yuan, Ruishou Ba, Ning Wang, Yuqing Zhang, Liwei Wang and Hongjie Yang
Sustainability 2024, 16(21), 9229; https://doi.org/10.3390/su16219229 - 24 Oct 2024
Abstract
The Tibetan Plateau is the “Asia Water Tower” and is pivotal for Asia and the whole world. Groundwater is essential for sustainable development in its alpine regions, yet its chemical quality increasingly limits its usability. The present research examines the hydrochemical characteristics and [...] Read more.
The Tibetan Plateau is the “Asia Water Tower” and is pivotal for Asia and the whole world. Groundwater is essential for sustainable development in its alpine regions, yet its chemical quality increasingly limits its usability. The present research examines the hydrochemical characteristics and origins of phreatic groundwater in alpine irrigation areas. The study probes the chemical signatures, quality, and regulatory mechanisms of phreatic groundwater in a representative alpine irrigation area of the Tibetan Plateau. The findings indicate that the phreatic groundwater maintains a slightly alkaline and fresh status, with pH values ranging from 7.07 to 8.06 and Total Dissolved Solids (TDS) between 300.25 and 638.38 mg/L. The hydrochemical composition of phreatic groundwater is mainly HCO3-Ca type, with a minority of HCO3-Na·Ca types, closely mirroring the profile of river water. Nitrogen contaminants, including NO3, NO2, and NH4+, exhibit considerable concentration fluctuations within the phreatic aquifer. Approximately 9.09% of the sampled groundwaters exceed the NO2 threshold of 0.02 mg/L, and 28.57% surpass the NH4+ limit of 0.2 mg/L for potable water standards. All sampled groundwaters are below the permissible limit of NO3 (50 mg/L). Phreatic groundwater exhibits relatively good potability, as assessed by the entropy-weighted water quality index (EWQI), with 95.24% of groundwaters having an EWQI value below 100. However, the potential health risks associated with elevated NO3 levels, rather than NO2 and NH4+, merit attention when such water is consumed by minors at certain sporadic sampling locations. Phreatic groundwater does not present sodium hazards or soil permeability damage, yet salinity hazards require attention. The hydrochemical makeup of phreatic groundwater is primarily dictated by rock–water interactions, such as silicate weathering and cation exchange reactions, with occasional influences from the dissolution of evaporites and carbonates, as well as reverse cation-exchange processes. While agricultural activities have not caused a notable rise in salinity, they are the main contributors to nitrogen pollution in the study area’s phreatic groundwater. Agricultural-derived nitrogen pollutants require vigilant monitoring to avert extensive deterioration of groundwater quality and to ensure the sustainable management of groundwater resources in alpine areas. Full article
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21 pages, 31333 KiB  
Article
Multiscale Characterization of Fractures and Analysis of Key Controlling Factors for Fracture Development in Tight Sandstone Reservoirs of the Yanchang Formation, SW Ordos Basin, China
by Peng Chen, Shuhan Yang, Xinyu Chen, Zeyu Li, Chuanbo Shen and Huaning Qiu
Appl. Sci. 2024, 14(21), 9676; https://doi.org/10.3390/app14219676 - 23 Oct 2024
Abstract
Tight sandstone reservoirs, despite their low porosity and permeability, present considerable exploration potential as unconventional hydrocarbon resources. Natural fractures play a crucial role in hydrocarbon migration, accumulation, and present engineering challenges such as late-stage reformation in these reservoirs. This study examines fractures in [...] Read more.
Tight sandstone reservoirs, despite their low porosity and permeability, present considerable exploration potential as unconventional hydrocarbon resources. Natural fractures play a crucial role in hydrocarbon migration, accumulation, and present engineering challenges such as late-stage reformation in these reservoirs. This study examines fractures in the seventh member of the Triassic Yanchang Formation’s tight sandstone within the Ordos Basin using a range of methods, including field outcrops, core samples, imaging and conventional logging, thin sections, and scanning electron microscopy. The study clarifies the characteristics of fracture development and evaluates the relationship between dynamic and static rock mechanics parameters, including the calculation of the brittleness index. Primary factors influencing fracture development were quantitatively assessed through a combination of outcrop, core, and mechanical test data. Findings reveal that high-angle structural fractures are predominant, with some bedding and diagenetic fractures also present. Acoustic, spontaneous potential, and caliper logging, in conjunction with imaging data, enabled the development of a comprehensive probabilistic index for fracture identification, which produced favorable results. The analysis identifies four key factors influencing fracture development: stratum thickness, brittleness index, lithology, and rock mechanical stratigraphy. Among these factors, stratum thickness is negatively correlated with fracture development. Conversely, the brittleness index positively correlates with fracture development and significantly influences fracture length, aperture, and linear density. Fractures are most prevalent in siltstone and fine sandstone, with minimal development in mudstone. Different rock mechanics layer types also impact fracture development. These insights into fracture characteristics and controlling factors are anticipated to enhance exploration efforts and contribute to the study of similar unconventional reservoirs. Full article
(This article belongs to the Section Earth Sciences)
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16 pages, 7495 KiB  
Article
Influence of Chemical Weathering and Microcracks on Permeability Variations in Crystalline Rocks
by Jinyoung Park, Seongwoo Jeong, Seonggan Jang, Juyeon Lee, Kyoungtae Ko and Minjune Yang
Water 2024, 16(20), 3007; https://doi.org/10.3390/w16203007 - 21 Oct 2024
Abstract
Rock permeability, an important factor in subsurface fluid migration, can be influenced by microcracks and chemical weathering due to water–rock interactions. Understanding the relationship between permeability, chemical weathering, and microcracks is crucial for assessing fluid flow in rocks. This study focuses on the [...] Read more.
Rock permeability, an important factor in subsurface fluid migration, can be influenced by microcracks and chemical weathering due to water–rock interactions. Understanding the relationship between permeability, chemical weathering, and microcracks is crucial for assessing fluid flow in rocks. This study focuses on the hydrogeological characteristics of granite and gneiss, potential host rocks for high-level radioactive waste disposal in South Korea. Samples were analyzed for permeability, porosity, P-wave velocity, and chemical weathering indices. Regression analysis revealed a weak correlation between permeability and both porosity and rock density, while an inverse correlation was observed between permeability and chemical weathering indices. Interestingly, some samples showed low permeability (10−21 to 10−22 m2) despite high weathering, while others showed high permeability (10−18 to 10−19 m2) despite low weathering. SEM-EDS analysis indicated the presence of microcracks within the rocks or the filling of these cracks with secondary minerals. The findings suggest that chemical weathering generally increases pore size and porosity, but actual permeability can vary depending on the presence and connectivity of microcracks and the extent to which they are filled with secondary minerals. Therefore, both chemical weathering and microcrack connectivity must be considered when evaluating the hydrogeological characteristics of crystalline rocks. Full article
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25 pages, 4217 KiB  
Article
Development of Potential Slip Surface Identification Model for Active Deep-Seated Landslide Sites: A Case Study in Taiwan
by Shih-Meng Hsu, Chun-Chia Hsiung, Yu-Jia Chiu, Yi-Fan Liao and Jie-Ru Lin
Geosciences 2024, 14(10), 276; https://doi.org/10.3390/geosciences14100276 - 18 Oct 2024
Viewed by 174
Abstract
Identifying locations of landslide slip surfaces provides critical information for understanding the volume of landslides and the scale of disasters, both of which are essential for formulating disaster preparedness and mitigation strategies. Based on hydrogeological survey data from 24 deep-seated landslide-prone sites in [...] Read more.
Identifying locations of landslide slip surfaces provides critical information for understanding the volume of landslides and the scale of disasters, both of which are essential for formulating disaster preparedness and mitigation strategies. Based on hydrogeological survey data from 24 deep-seated landslide-prone sites in Taiwan’s mountainous regions, this study developed the hydraulic conductivity potential index (HCPI) using principal component analysis to quantify the hydraulic properties of disturbed rock formations with six geological factors. Then, regression analysis was performed to construct a permeability estimation model for the geological environment of landslides. Finally, the established model was utilized to develop an identification method for potential slip depths in landslide-prone sites. Results indicated a strong relation between HCPI and hydraulic conductivity with a determination coefficient of 0.895. The relation equation confirmed that the data it generated concerning the depths of significant changes in hydraulic conductivity could be used to identify potential slip surfaces. Additionally, this study successfully established a rule for identifying potential slip zones by summarizing data concerning the generated hydraulic conductivity profiles, stratigraphic lithology, existing inclinometer slip depth records, and groundwater level of landslide sites. This identification method was then applied to predict potential slip depths for ten landslide sites where slip surfaces have not yet occurred. These findings offer a new alternative to having early information on potential sliding depths for timely disaster management and control implementation. Full article
(This article belongs to the Section Natural Hazards)
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14 pages, 775 KiB  
Article
Nutritional Status, Diet, and Intestinal Permeability of Mexican Children with Autism Spectrum Disorders
by Karina Alejandra Pedroza-García, Miriam Aracely Anaya-Loyola, Dolores Ronquillo, María del Carmen Caamaño, David Masuoka, Jorge Palacios-Delgado and Jorge L. Rosado
Gastroenterol. Insights 2024, 15(4), 912-925; https://doi.org/10.3390/gastroent15040064 - 16 Oct 2024
Viewed by 338
Abstract
Introduction: Autism spectrum disorder (ASD) comprises a group of developmental disorders characterized by deficits in social interaction and behavioral patterns. Children with ASD may face nutritional challenges, primarily due to their restrictive behaviors and frequent gastrointestinal issues. Objective: The objective of the present [...] Read more.
Introduction: Autism spectrum disorder (ASD) comprises a group of developmental disorders characterized by deficits in social interaction and behavioral patterns. Children with ASD may face nutritional challenges, primarily due to their restrictive behaviors and frequent gastrointestinal issues. Objective: The objective of the present study was to assess nutritional status, dietary habits, and intestinal permeability in a sample of individuals with ASD. Methods: A cross-sectional study was conducted with 24 children and adolescents (both sexes), aged 4 to 18 years, living in two cities of Mexico (Aguascalientes and Querétaro). Weight and height were measured, and body mass index for age was calculated and compared using WHO Z-scores. Diet was assessed through three 24 h dietary recalls and a food frequency questionnaire. Intestinal permeability was evaluated using a lactulose/mannitol test by HPLC. Results: A high prevalence of malnutrition was observed; 12.5% of the participants were underweight, and 45.8% were overweight or obese. Children had a low intake of fiber, vitamin E, folate, potassium, zinc, and phosphorus and a high intake of sodium. On average, the intestinal permeability ratio was 0.09 ± 0.05, with 54.2% of the children exhibiting high intestinal permeability. Conclusions: It is advisable to develop food counseling strategies for children with ASD to prevent micronutrient deficiencies, promote healthy weight, and improve gastrointestinal integrity. Full article
(This article belongs to the Section Gastrointestinal Disease)
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34 pages, 7963 KiB  
Article
Impact of Lyophilized Milk Kefir-Based Self-Nanoemulsifying System on Cognitive Enhancement via the Microbiota–Gut–Brain Axis
by Mai M. Anwar, Amira A. Boseila, Abeer A. Mabrouk, Abdelfattah A. Abdelkhalek and Amr Amin
Antioxidants 2024, 13(10), 1205; https://doi.org/10.3390/antiox13101205 - 7 Oct 2024
Viewed by 493
Abstract
Chronic inflammatory bowel disorders (IBDs) are characterized by altered intestinal permeability, prompting inflammatory, oxidative stress, and immunological factors. Gut microbiota disorders impact brain function via the bidirectional gut–brain axis, influencing behavior through inflammatory cascades, oxidative stress, and neurotransmitter levels. This study highlights the [...] Read more.
Chronic inflammatory bowel disorders (IBDs) are characterized by altered intestinal permeability, prompting inflammatory, oxidative stress, and immunological factors. Gut microbiota disorders impact brain function via the bidirectional gut–brain axis, influencing behavior through inflammatory cascades, oxidative stress, and neurotransmitter levels. This study highlights the potential effect of integrating lyophilized milk kefir alone and lyophilized milk kefir as solid carriers loaded with a self-nanoemulsifying self-nanosuspension (SNESNS) of licorice extract on an induced chronic IBD-like model in rats. Licorice-SNESNS was prepared by the homogenization of 30 mg of licorice extract in 1 g of the selected SNEDDS (30% Caraway oil, 60% Tween 20, and 10% propylene glycol (w/w)). Licorice-SNESNS was mixed with milk kefir and then freeze-dried. Dynamic TEM images and the bimodal particle size curve confirmed the formation of the biphasic nanosystems after dilution (nanoemulsion and nanosuspension). Daily oral administration of lyophilized milk kefir (100 mg/kg) loaded with SNESNS (10 mg/kg Caraway oil and 1 mg/kg licorice) restored normal body weight and intestinal mucosa while significantly reducing submucosal inflammatory cell infiltration in induced rats. Importantly, this treatment demonstrated superior efficacy compared to lyophilized milk kefir alone by leading to a more significant alleviation of neurotransmitter levels and improved memory functions, thereby addressing gut–brain axis disorders. Additionally, it normalized fecal microbiome constituents, inflammatory cytokine levels, and oxidative stress in examined tissues and serum. Moreover, daily administration of kefir-loaded SNESNS normalized the disease activity index, alleviated histopathological changes induced by IBD induction, and partially restored the normal gut microbiota. These alterations are associated with improved cognitive functions, attributed to the maintenance of normal neurotransmitter levels and the alleviation of triggered inflammatory factors and oxidative stress levels. Full article
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18 pages, 3067 KiB  
Article
QbD Approach for the Development of Tea Tree Oil-Enhanced Microemulgel Loaded with Curcumin and Diclofenac for Rheumatoid Arthritis Treatment
by Shivam Pathak, Ruhi Singh, Afzal Hussain, Nasir Ali Siddiqui, Saurabh Mittal and Annie Gupta
Gels 2024, 10(10), 634; https://doi.org/10.3390/gels10100634 - 30 Sep 2024
Viewed by 529
Abstract
Rheumatoid arthritis, a chronic autoimmune disorder affecting millions worldwide each year, poses a significant threat due to its potential for progressive joint damage and debilitating pain if left untreated. Topical anti-inflammatory and analgesic treatments offer localized relief with reduced systemic side effects compared [...] Read more.
Rheumatoid arthritis, a chronic autoimmune disorder affecting millions worldwide each year, poses a significant threat due to its potential for progressive joint damage and debilitating pain if left untreated. Topical anti-inflammatory and analgesic treatments offer localized relief with reduced systemic side effects compared to conventional oral therapies, making them a promising option for managing rheumatoid arthritis. Therefore, the current study endeavored to formulate a microemulsion gel formulation loaded with diclofenac and curcumin for topical administration in the management of rheumatoid arthritis, utilizing Tea tree oil. The ratio of surfactant and cosurfactant was 4:1, assessed by pseudoternary phase diagram on the basis of the maximum emulsification region. The microemulsion underwent optimization using a Central Composite Rotatable Design (CCRD) with constraints of minimum particle size, polydispersity index, and maximum transmittance. The Curcufenac-T microemulsion had a particle size, polydispersity index (PDI), and transmittance of 151.82 ± 15.9 nm, 0.287 ± 0.021, and −5.78 ± 0.26 mV, respectively. DSC analyses confirmed the stability and compatibility of diclofenac and curcumin within the formulation. The microemulsion was changed into gel form by incorporating 1% carbopol-934. Skin permeation analysis revealed that the percentage of diclofenac permeated at 0.5 h from Curcufenac-T microemugel and the conventional gel was 12.1% and 3.9%, respectively, while at 12 h, the rates were 82.6% and 34.2%, respectively. In vitro permeability demonstrated significant potential for the effective delivery of diclofenac and curcumin to targeted sites, compared to conventional gel. Therefore, it was deduced that the Tea tree oil integrated diclofenac and curcumin microemulsion gel could enhance the effectiveness of diclofenac and serve as a promising vehicle for rheumatoid arthritis treatment. Full article
(This article belongs to the Special Issue Synthetic, Natural and Hybrid Gels Intended for Various Applications)
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17 pages, 1517 KiB  
Article
Effects of a Sorghum Beverage with Lacticaseibacillus paracasei on Body Composition, Lipid Profiles, and Intestinal Health in Overweight and Obese Adults: A Randomized Single-Blind Pilot Study
by Lucimar Aguiar da Silva, Vinícius Parzanini Brilhante de São José, Larissa Arruda Rodrigues, Pietra Vidal Cardoso do Prado, Renata Celi Lopes Toledo, Frederico Augusto Ribeiro de Barros, Andressa Moreira de Souza, Rosemar Antoniassi, Carlos Wanderlei Piler de Carvalho, Valéria Aparecida Vieira Queiroz, Karina Maria Olbrich dos Santos, Joseph Francis Pierre, Bárbara Pereira da Silva and Hércia Stampini Duarte Martino
Foods 2024, 13(19), 3128; https://doi.org/10.3390/foods13193128 - 30 Sep 2024
Viewed by 782
Abstract
(1) Background: This study aimed to evaluate the effect of an extruded whole-grain sorghum beverage containing L. paracasei on body composition, lipid profiles, and intestinal health in overweight and obese adults. (2) Methods: A chronic, single-blind randomized controlled pilot study was conducted with [...] Read more.
(1) Background: This study aimed to evaluate the effect of an extruded whole-grain sorghum beverage containing L. paracasei on body composition, lipid profiles, and intestinal health in overweight and obese adults. (2) Methods: A chronic, single-blind randomized controlled pilot study was conducted with 30 volunteers allocated to three groups (n = 10/group): extruded sorghum beverage (ESB), extruded sorghum beverage with L. paracasei (ESPB), and control beverage (CB) (waxy maize starch). The chemical composition of the beverages was analyzed. Volunteers consumed the beverages for ten weeks at breakfast, along with individual dietary prescriptions. Body composition, biochemical markers, gastrointestinal symptoms, stool consistency, intestinal permeability, short-chain fatty acids, fecal pH, and stool L. paracasei DNA concentration were analyzed at the beginning and end of the intervention period. (3) Results: The ESB showed better composition than the CB, particularly in terms of resistant starch content, total phenolic compounds, condensed tannins, and antioxidant capacity. Both the ESB and the ESPB had an effect on body composition (estimated total visceral fat and waist volume), biochemical markers (Castelli index I), and intestinal health (Bristol scale, diarrhea score, valeric acid, and L. paracasei DNA concentration). No changes were observed in the CB group after the intervention. (4) Conclusions: Whole-grain sorghum beverages demonstrated good nutritional value, and consumption of these beverages, with or without L. paracasei, provided health benefits, including improvements in body composition, Castelli index I scores, and intestinal health, in overweight and obese adults. Full article
(This article belongs to the Section Grain)
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15 pages, 3257 KiB  
Article
Tight Oil Well Productivity Prediction Model Based on Neural Network
by Yuhang Jin, Kangliang Guo, Xinchen Gao and Qiangyu Li
Processes 2024, 12(10), 2088; https://doi.org/10.3390/pr12102088 - 26 Sep 2024
Viewed by 318
Abstract
Productivity prediction has always been an important part of reservoir development, and tight reservoirs need accurate and efficient productivity prediction models. Due to the complexity of the tight oil reservoir, the data obtained by the detection instrument need to extract data features at [...] Read more.
Productivity prediction has always been an important part of reservoir development, and tight reservoirs need accurate and efficient productivity prediction models. Due to the complexity of the tight oil reservoir, the data obtained by the detection instrument need to extract data features at a deeper level. Using the Pearson correlation coefficient and partial correlation coefficient to analyze the main control of productivity factors, eight characteristic parameters of volume coefficient, water saturation, density, effective thickness, skin factor, shale content, porosity, and effective permeability were obtained, and the specific oil production index was used as the target parameter. Two sample structures of pure static parameters and dynamic and static parameters (shale content, effective permeability, porosity, water saturation, and density as dynamic parameters, volume coefficient, skin factor, and effective thickness as static parameters) were created, and corresponding model structures (BP (Backpropagation), neural network model, and LSTM-BP (Long Short-Term Memory Backpropagation) neural network model) were designed to compare the prediction effects of models under different sample structures. The mean absolute error, root mean square error, mean relative percentage error, and coefficient of determination were used to evaluate the model results. The LSTM-BP neural network was used to predict the production capacity of the test set. The results showed that the average absolute error was 0.07, the root mean square error was 0.10, the average absolute percentage error was 21%, and the coefficient of determination was 0.97. Using wells in the WZ area for testing, the LSTM-BP model’s predictions are evenly distributed on both sides of the 45° line, separating the predicted values from actual values, with errors from the line being relatively small. In contrast, the BP model and analytical method are unable to achieve such an even distribution around the line. Experiments show that the LSTM-BP neural network model can effectively extract dynamic parameter features and has a stronger generalization ability. Full article
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13 pages, 7185 KiB  
Article
Melatonin Treatment Alleviates Chilling Injury of Loquat Fruit via Modulating ROS Metabolism
by Jiahui Wan, Yanting Wu, Zhihong Tong, Wenbing Su, Hetong Lin and Zhongqi Fan
Foods 2024, 13(19), 3050; https://doi.org/10.3390/foods13193050 - 25 Sep 2024
Viewed by 490
Abstract
Cold storage is one of the most effective methods to maintain postharvest fruit quality. However, loquat fruits are prone to chilling injury (CI) during cold storage, appearing as symptoms such as browning and pitting, which leads to quality deterioration and economic losses. In [...] Read more.
Cold storage is one of the most effective methods to maintain postharvest fruit quality. However, loquat fruits are prone to chilling injury (CI) during cold storage, appearing as symptoms such as browning and pitting, which leads to quality deterioration and economic losses. In this study, the effects of melatonin on CI alleviation and the potential role of reactive oxygen species (ROS) metabolism in loquat fruit were investigated. The results showed that 50 μM melatonin was the optimal concentration to inhibit the increase in CI index and cell membrane permeability. Moreover, compared to control fruits, 50 μM melatonin inhibited the malonaldehyde (MDA) content, O2−. production rate and H2O2 content (ROS accumulation) by 17.8%, 7.2% and 11.8%, respectively, during cold storage. Compared to non-treated loquats, 50 μM melatonin maintained higher levels of 1-diphenyl-2-picrylhydrazyl radical-scavenging ability and reducing power, as well as the contents of ascorbic acid (AsA) and glutathione (GSH). Additionally, 50 μM melatonin enhanced the activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) by increasing relevant gene expressions. The activities of SOD, CAT and APX were increased by up to 1.1-, 1.1- and 1.1-times (16 d) by melatonin, as compared with the control fruits. These findings indicate that melatonin mitigation of CI is involved in maintaining cellular redox apphomeostasis in loquat fruit during cold storage. Full article
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23 pages, 3961 KiB  
Article
Multivariate Statistical Approach and Assessment of Pollution of Water and Sediments in Karstic Springs of Transboundary Aquifer Žumberak–Samoborsko Gorje Mountain (Croatia/Slovenia)
by Nenad Buzjak, Natalija Matić, Krešimir Maldini and Vinod Jena
Water 2024, 16(19), 2718; https://doi.org/10.3390/w16192718 - 24 Sep 2024
Viewed by 734
Abstract
This study highlights the geochemistry of water and sediments of the karstic springs of the transboundary aquifer (TBA) Žumberak–Samoborsko Gorje Mt. (NW Croatia). After calculating pollution indices, the analysis showed that the sediments are unpolluted. The geo-accumulation index (Igeo) showed only the elements [...] Read more.
This study highlights the geochemistry of water and sediments of the karstic springs of the transboundary aquifer (TBA) Žumberak–Samoborsko Gorje Mt. (NW Croatia). After calculating pollution indices, the analysis showed that the sediments are unpolluted. The geo-accumulation index (Igeo) showed only the elements Ba and Rb, indicating moderate levels of pollution, with the highest values in springs Vapnik and Bistrac. Statistical analysis confirmed their natural origin. The water of these springs is under possible anthropogenic influence as indicated by elevated concentrations of total nitrogen (TN) and total phosphorus (TP). According to a principal component analysis (PCA) for elements in sediments, PC1 described a combined lithogenic and oxidative–reductive influence, PC2 described a combined geological background including total organic carbon (TOC) content and oxidative–reductive influence, while TOC had the greatest influence on PC3. Depending on element composition, the factor scores related to PC1 and PC2 resulted in two different groups of sites, while the factor scores concerning PC1 and PC3 did not show separation in two groups. The hierarchical cluster analysis showed three clusters in relation to the content of the elements. The correlation coefficient between the sediment and related water samples showed that the springs placed in a low-permeability formation (dolomite) had a strong positive coefficient of correlation. Full article
(This article belongs to the Section Hydrogeology)
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18 pages, 6286 KiB  
Article
The Gas Production Characteristics of No. 3 Coal Seam Coalbed Methane Well in the Zhengbei Block and the Optimization of Favorable Development Areas
by Cong Zhang, Qiujia Hu, Chunchun Liu, Huimin Jia, Guangjie Sang, Dingquan Wu, Kexin Li and Qian Wang
Processes 2024, 12(9), 2018; https://doi.org/10.3390/pr12092018 - 19 Sep 2024
Viewed by 424
Abstract
The characteristics and influencing factors of gas production in CBM wells are analyzed based on the field geological data and the productivity data of coalbed methane (CBM) wells in the Zhengbei block, and then the favorable areas are divided. The results show that [...] Read more.
The characteristics and influencing factors of gas production in CBM wells are analyzed based on the field geological data and the productivity data of coalbed methane (CBM) wells in the Zhengbei block, and then the favorable areas are divided. The results show that the average gas production of No. 3 coal seam CBM wells in the study area is in the range of 0~1793 m3/d, with an average of 250.97 m3/d; 80% of the wells are less than 500 m3/d, and there are fewer wells above 1000 m3/d. The average gas production is positively correlated with gas content, critical desorption pressure, permeability, Young’s modulus, and Schlumberger ratio, and negatively correlated with fracture index, fault fractal dimension, Poisson’s ratio, and horizontal stress difference coefficient. The relationship between coal seam thickness and the minimum horizontal principal stress is not strong. The low-yield wells have the characteristics of multiple pump-stopping disturbances, unstable casing pressure control, overly rapid pressure reduction in the single-phase flow stage, sand and pulverized coal production, and high-yield water in the later stage during the drainage process. It may be caused by the small difference in compressive strength between the roof and floor and the coal seam, and the small difference in the Young’s modulus of the floor. The difference between the two high-yield wells is large, and the fracturing cracks are easily controlled in the coal seam and extend along the level. The production control factors from strong to weak are as follows: critical desorption pressure, permeability, Schlumberger ratio, fault fractal dimension, Young’s modulus, horizontal stress difference coefficient, minimum horizontal principal stress, gas content, Poisson’s ratio, fracture index, coal seam thickness. The type I development unit (development of favorable areas) of the Zhengbei block is interspersed with the north and south of the block on the plane, and the III development unit is mainly located in the east of the block and near the Z-56 well. The comprehensive index has a significant positive correlation with the gas production, and the prediction results are accurate. Full article
(This article belongs to the Special Issue Advances in Enhancing Unconventional Oil/Gas Recovery, 2nd Edition)
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25 pages, 13281 KiB  
Article
Dilation Potential Analysis of Low-Permeability Sandstone Reservoir under Water Injection in the West Oilfield of the South China Sea
by Huan Chen, Yanfeng Cao, Jifei Yu, Yingwen Ma, Yanfang Gao, Shaowei Wu, Hui Yuan, Minghua Zou, Dengke Li, Xinjiang Yan and Jianlin Peng
Processes 2024, 12(9), 2015; https://doi.org/10.3390/pr12092015 - 19 Sep 2024
Viewed by 445
Abstract
At present, many offshore oil fields are facing problems, such as pollution-induced near-well zone blockage, poor inter-well connectivity, and strong vertical heterogeneity, which lead to insufficient formation energy and low production in the middle and late stages of development. It is necessary to [...] Read more.
At present, many offshore oil fields are facing problems, such as pollution-induced near-well zone blockage, poor inter-well connectivity, and strong vertical heterogeneity, which lead to insufficient formation energy and low production in the middle and late stages of development. It is necessary to develop a new technology to overcome these issues. In this regard, water-injection-induced dilation technology, which was already proven to have positive effects on loose sandstone reservoirs, was controversially applied to an offshore low-permeability reservoir. To investigate whether the water-injection-induced dilation technology is suitable, experiments were conducted to analyze the dilation potential of offshore low-permeability sandstone reservoirs, namely, X-ray diffraction, laser particle size analysis, physical simulation, computed tomography scan, and electron microscope scanning experiments. The X-ray diffraction experiments showed that the samples had more than 80% non-clay mineral content and a high brittleness index, which meant more complex microfractures under water injection. Particle size analysis experiments revealed that the particle size was mainly between 10 μm and 100 μm, and thus belonged to coarse silty sand. According to the sorting grade, the sample particle size distribution was uniform and the reservoir was more prone to dilation. The true triaxial physical simulation showed that a volumetric dilation zone occurred around the wellbore, where complicated microfractures occurred. This paper provides adequate evidence and mechanisms of dilation potential for an offshore low-permeability sandstone reservoir. Full article
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20 pages, 1937 KiB  
Article
Design and Characterization of Liposomal-Based Carriers for the Encapsulation of Rosa canina Fruit Extract: In Vitro Gastrointestinal Release Behavior
by Aleksandra A. Jovanović, Bojana Balanč, Predrag M. Petrović, Mina Volić, Darko Micić, Jelena Živković and Katarina P. Šavikin
Plants 2024, 13(18), 2608; https://doi.org/10.3390/plants13182608 - 18 Sep 2024
Viewed by 484
Abstract
The increasing demand for natural compounds as an alternative to synthetic antioxidants and conservans has led to the utilization of secondary plant metabolites in the food industry, as these bioactive compounds possess great antioxidative and antimicrobial properties without side effects on human health. [...] Read more.
The increasing demand for natural compounds as an alternative to synthetic antioxidants and conservans has led to the utilization of secondary plant metabolites in the food industry, as these bioactive compounds possess great antioxidative and antimicrobial properties without side effects on human health. Despite this, the sensitivity of plant-derived compounds is a restrictive factor in terms of their full potential. The current research aimed to characterize rosehip-fruit-extract-loaded liposomes (non-treated and UV-irradiated) in terms of their density, surface tension, viscosity, chemical composition (FTIR and HPLC analyses), and thermal behavior. In the storage stability study, the vesicle size, polydispersity index (PDI), zeta potential, conductivity, and mobility of the liposomes were monitored. FTIR analysis confirmed that the plant compounds were successfully loaded within the carrier, while no chemical reaction between the rosehip fruit extract and phospholipids was detected. The results of the HPLC analysis evidence the high potential for liposomal encapsulation to protect sensitive bioactives in the rosehip fruit extract from the degrading effect of UV irradiation. The size of the rosehip-fruit-extract-encapsulated liposomes increased on the seventh day of storage from 250 nm to 300 nm, while the zeta potential values were between −21 mV and −30 mV in the same period and further stabilized over 60 days of monitoring. In Vitro release studies in water and simulated gastrointestinal fluids showed that the presence of enzymes and bile salts (in intestinal fluid) enhanced the rosehip–polyphenol permeability from liposomes (70.3% after 6 h) compared with their release in water after 24 h and in gastric fluid after 4 h (38.9% and 41.4%, respectively). The obtained results indicate that the proliposome method was an effective method for rosehip fruit extract liposomal encapsulation and for the delivery of these plant-derived bioactives in foods. Full article
(This article belongs to the Section Phytochemistry)
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18 pages, 2698 KiB  
Article
ANT-Mediated Inhibition of the Permeability Transition Pore Alleviates Palmitate-Induced Mitochondrial Dysfunction and Lipotoxicity
by Natalia V. Belosludtseva, Anna I. Ilzorkina, Dmitriy A. Serov, Mikhail V. Dubinin, Eugeny Yu. Talanov, Maxim N. Karagyaur, Alexandra L. Primak, Jiankang Liu and Konstantin N. Belosludtsev
Biomolecules 2024, 14(9), 1159; https://doi.org/10.3390/biom14091159 - 15 Sep 2024
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Abstract
Hyperlipidemia is a major risk factor for vascular lesions in diabetes mellitus and other metabolic disorders, although its basis remains poorly understood. One of the key pathogenetic events in this condition is mitochondrial dysfunction associated with the opening of the mitochondrial permeability transition [...] Read more.
Hyperlipidemia is a major risk factor for vascular lesions in diabetes mellitus and other metabolic disorders, although its basis remains poorly understood. One of the key pathogenetic events in this condition is mitochondrial dysfunction associated with the opening of the mitochondrial permeability transition (MPT) pore, a drop in the membrane potential, and ROS overproduction. Here, we investigated the effects of bongkrekic acid and carboxyatractyloside, a potent blocker and activator of the MPT pore opening, respectively, acting through direct interaction with the adenine nucleotide translocator, on the progression of mitochondrial dysfunction in mouse primary lung endothelial cells exposed to elevated levels of palmitic acid. Palmitate treatment (0.75 mM palmitate/BSA for 6 days) resulted in an 80% decrease in the viability index of endothelial cells, which was accompanied by mitochondrial depolarization, ROS hyperproduction, and increased colocalization of mitochondria with lysosomes. Bongkrekic acid (25 µM) attenuated palmitate-induced lipotoxicity and all the signs of mitochondrial damage, including increased spontaneous formation of the MPT pore. In contrast, carboxyatractyloside (10 μM) stimulated cell death and failed to prevent the progression of mitochondrial dysfunction under hyperlipidemic stress conditions. Silencing of gene expression of the predominate isoform ANT2, similar to the action of carboxyatractyloside, led to increased ROS generation and cell death under conditions of palmitate-induced lipotoxicity in a stably transfected HEK293T cell line. Altogether, these results suggest that targeted manipulation of the permeability transition pore through inhibition of ANT may represent an alternative approach to alleviate mitochondrial dysfunction and cell death in cell culture models of fatty acid overload. Full article
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