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1.
Theranostics ; 14(8): 3282-3299, 2024.
Article de Anglais | MEDLINE | ID: mdl-38855179

RÉSUMÉ

Rationale: Pharmacological targeting of mitochondrial ion channels is developing as a new direction in cancer therapy. The opening or closing of these channels can impact mitochondrial function and structure by interfering with intracellular ion homeostasis, thereby regulating cell fate. Nevertheless, their abnormal expression or regulation poses challenges in eliminating cancer cells, and further contributes to metastasis, recurrence, and drug resistance. Methods: We developed an engineered mitochondrial targeted delivery system with self-reinforcing potassium ion (K+) influx via amphiphilic mitochondrial targeting polymer (TMP) as carriers to co-deliver natural K+ channel agonists (Dinitrogen oxide, DZX) and artificial K+ channel molecules (5F8). Results: Using this method, DZX specifically activated natural K+ channels, whereas 5F8 assembled artificial K+ channels on the mitochondrial membrane, leading to mitochondrial K+ influx, as well as oxidative stress and activation of the mitochondrial apoptotic pathway. Conclusion: The synergistic effect of 5F8 and DZX presents greater effectiveness in killing cancer cells than DZX alone, and effectively inhibited tumor recurrence and lung metastasis following surgical resection of breast cancer tumors in animal models. This strategy innovatively integrates antihypertensive drugs with artificial ion channel molecules for the first time to effectively inhibit tumor recurrence and metastasis by disrupting intracellular ion homeostasis, which will provide a novel perspective for postoperative tumor therapy.


Sujet(s)
Homéostasie , Mitochondries , Animaux , Mitochondries/métabolisme , Mitochondries/effets des médicaments et des substances chimiques , Humains , Homéostasie/effets des médicaments et des substances chimiques , Souris , Lignée cellulaire tumorale , Femelle , Récidive tumorale locale/prévention et contrôle , Tumeurs du sein/traitement médicamenteux , Tumeurs du sein/anatomopathologie , Tumeurs du sein/métabolisme , Apoptose/effets des médicaments et des substances chimiques , Potassium/métabolisme , Tumeurs du poumon/traitement médicamenteux , Tumeurs du poumon/secondaire , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/métabolisme , Souris de lignée BALB C , Canaux ioniques/métabolisme , Canaux potassiques/métabolisme , Souris nude , Métastase tumorale
2.
World J Otorhinolaryngol Head Neck Surg ; 10(2): 113-120, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38855290

RÉSUMÉ

Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.

3.
Article de Chinois | MEDLINE | ID: mdl-38858107

RÉSUMÉ

Non-steroidal anti-inflammatory drugs-exacerbated respiratory disease (N-ERD) is a chronic respiratory disease characterized by eosinophilic inflammation, featuring chronic rhinosinusitis (CRS), asthma, and intolerance to cyclooxygenase 1 (COX-1) inhibitors. The use of these medications can lead to an acute worsening of rhinitis and asthma symptoms. This condition has not yet received sufficient attention in China, with a high rate of misdiagnosis and a lack of related research. The Chinese Rhinology Research Group convened a group of leading young experts in otolaryngology from across the country, based on the latest domestic and international evidence-based medical practices to formulate this consensus.The consensus covers the epidemiology, pathogenesis, clinical manifestations, diagnostic methods, and treatment strategies for N-ERD, including pharmacotherapy, surgery, biologic treatments, and desensitization therapy. The goal is to improve recognition of N-ERD, reduce misdiagnosis, and enhance treatment outcomes.


Sujet(s)
Anti-inflammatoires non stéroïdiens , Humains , Anti-inflammatoires non stéroïdiens/effets indésirables , Chine , Rhinite/diagnostic , Rhinite/thérapie , Rhinite/induit chimiquement , Sinusite/diagnostic , Sinusite/thérapie , Sinusite/traitement médicamenteux , Consensus , Asthme/diagnostic , Asthme/traitement médicamenteux , Maladie chronique
4.
Opt Express ; 32(8): 13342-13356, 2024 Apr 08.
Article de Anglais | MEDLINE | ID: mdl-38859307

RÉSUMÉ

Phase shifting profilometry is an important technique for reconstructing the three-dimensional (3D) geometry of objects with purely diffuse surfaces. However, it is challenging to measure the transparent objects due to the pattern aliasing caused by light refraction and multiple reflections inside the object. In this work, we analyze the aliasing fringe pattern formation for transparent objects and then, propose to learn the front surface light intensity distribution based on the formation principle by using the diffusion models for generating the non-aliased fringe patterns reflected from the front surface only. With the generated fringe patterns, the 3D shape of the transparent objects can be reconstructed via the conventional structured light. We show the feasibility and performance of the proposed method on the data of purely transparent objects that are not seen in the training stage. Moreover, we found it could be generalized to other cases with local-transparent and translucent objects, showing the potential capability of the diffusion based learnable framework in tackling the problems of transparent object reconstruction.

5.
Article de Anglais | MEDLINE | ID: mdl-38865851

RÉSUMÉ

The Zingiberis Rhizoma - Jujubae Fructus herb pair (ZJHP) is a classic herb pair in traditional Chinese medicine. The herb pair shows the effect of dispelling cold, harmonizing the middle and improving gastrointestinal function, and is widely used for patients with stomach cold syndrome (SCS), stomachache and anemofrigid cold. The gingerols, shogaols, flavonoids and triterpenic acids are the important bioactive ingredients of ZJHP. However, few pharmacokinetic studies have been investigated in vivo for the above compounds. To comprehend the kinetics of active components and promote their curative application, a fast and sensitive ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS/MS) method was established for simultaneous determination of 12 analytes in normal and SCS rats in this study. The results showed that the pharmacokinetic parameters (Cmax, Tmax, t1/2z, MRT0-t, AUC0-t and AUC0-∞) in SCS model were significantly different from those in normal rats. In addition, the pharmacokinetics of rats given ZJHP were also varied from single herb oral administration, especially in model condition. These results indicated that the in vivo processes of the above analytes changed under pathological conditions and the compatibility of the herb pair could significantly influence the absorption of active components, which might provide an insight and further supports for the clinical application of ZJHP.

6.
Sci Total Environ ; : 174054, 2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38897466

RÉSUMÉ

Up to date, most studies reported that degradation is worsened in the grassland ecosystems of Inner Mongolia and adjacent regions as a result of intensified grazing. This seems to be scientific when considering the total forage or total above-ground biomass as a degradation indicator, but it does not hold true in terms of soil organic carbon density (SOCD). In this study, we quantified the changes of grassland ecosystem carbon stock in Inner Mongolia and adjacent regions from the 1980s to 2000s and identified the major drivers influencing these variations, using the National Grassland Resource Inventory and Soil Survey Dataset in 1980s and the Inventory data during 2002 to 2009 covering 624 sampling plots concerned vegetal traits and edaphic properties across the study region. The result indicated that the above-, below-ground and total vegetation biomass declined from 1980s to 2000s by ~10 %. However, total forage production increased by 6.72 % when considering livestock intake. SOCD remained stable despite a 67 % increase in grazing intensity. A generalized linear model (GLIM) analysis suggested that an increase in grazing intensity from the 1980s to 2000s could only explain 1.04 % of the total biomass change, while changes in precipitation and temperature explained 17.7 % (p < 0.05) of total vegetation biomass (TVB) change. Meanwhile, SOCD change during 1980s - 2000s could be explained 10.08 % by the soil texture (p < 0.05) and <1.6 % by changes in climate and livestock. This implies that the impacts of climate change on grassland biomass are more significant than those of grazing utilization, and SOCD was resistant to both climate change and intensified grazing. Overall, intensified grazing did not result in significant negative impacts on the grassland carbon stocks in the study region during the 1980s and 2000s. The grassland ecosystems possess a mechanism to adjust their root-shoot ratio, enabling them to maintain resilience against grazing utilization.

7.
Cell Biochem Funct ; 42(4): e4078, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38898665

RÉSUMÉ

Zinc finger proteins (ZNFs) play a significant role in the initiation and progression of tumors. Nevertheless, the specific contribution of ZNF610 to lung adenocarcinoma (LUAD) remains poorly understood. This study sought is to elucidate the role of ZNF610 in LUAD. Transcript data of LUAD were obtained from The Cancer Genome Atlas Program (TCGA) database and processed via R program. The expression of ZNF610 was assessed in various cell lines. To compare the proliferative capacity of cells with or without ZNF610 silencing, CCK8, cell colony formation assay, and Celigo label-free cell counting assay were employed. Furthermore, transwell migration and invasion assays were conducted to evaluate the migratory and invasive abilities of the cells. The expression levels of genes and proteins were assessed using quantitative real-time polymerase chain reaction (qRT-PCR) and western blot techniques. In different LUAD cells, the expression level of ZNF610 was found to be significantly higher in LUAD cells compared to MRC-5 and BASE-2B cells. Moreover, the silencing of ZNF610 resulted in a decrease in cell proliferation and migration abilities. Additionally, the apoptosis rate of cells increased upon silencing ZNF610. Notably, the proportion of cells in the G0/G1 phase increased, while the proportion of cells in the S phase decreased following ZNF610 silencing. Finally, ß-catenin and snail were identified as downstream targets of ZNF610 in cells. Our findings suggest that silencing ZNF610 could inhibit LUAD cell proliferation and migration, possibly through the downregulation of ß-catenin and snail.


Sujet(s)
Adénocarcinome pulmonaire , Mouvement cellulaire , Prolifération cellulaire , Tumeurs du poumon , Humains , Adénocarcinome pulmonaire/anatomopathologie , Adénocarcinome pulmonaire/métabolisme , Adénocarcinome pulmonaire/génétique , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/métabolisme , Tumeurs du poumon/génétique , Extinction de l'expression des gènes , Lignée cellulaire tumorale , Apoptose
8.
Clin Oral Investig ; 28(7): 385, 2024 Jun 19.
Article de Anglais | MEDLINE | ID: mdl-38890168

RÉSUMÉ

OBJECTIVES: Robots are increasingly being used for surgical procedures in various specialties. However, information about the accuracy of robot-assisted dental implant surgery is lacking. This pilot clinical study aimed to investigate the accuracy of an autonomous dental implant robotic (ADIR) system in partially edentulous cases. MATERIAL AND METHODS: The ADIR system was used to place a total of 20 implants in 13 participants. Implant deviation from the planned positions was assessed to determine accuracy. The entry, apex, and angular deviations were described as means ± standard deviation. A two-sample t test was used to compare implant deviation between the flap and flapless groups and between maxillary and mandibular implants (α = .05). RESULTS: The entry, apex, and angular deviations were 0.65 ± 0.32 mm, 0.66 ± 0.34 mm, and 1.52 ± 1.01°, respectively, with no statistically significant difference between the flap and flapless approaches (P > .05). No adverse events were encountered in any of the participants. CONCLUSIONS: DIR accuracy in this clinical series was comparable to that reported for static and dynamic computer-assisted implant surgery. Robotic computer-assisted implant surgery may be useful for dental implant placement, potentially improving the quality and safety of the procedure. CLINICAL RELEVANCE: The findings of this study showed that the ADIR system could be useful for dental implant surgery.


Sujet(s)
Pose d'implant dentaire endo-osseux , Mâchoire partiellement édentée , Humains , Projets pilotes , Mâle , Femelle , Adulte d'âge moyen , Pose d'implant dentaire endo-osseux/méthodes , Mâchoire partiellement édentée/chirurgie , Adulte , Interventions chirurgicales robotisées/instrumentation , Interventions chirurgicales robotisées/méthodes , Implants dentaires , Résultat thérapeutique
9.
Medicine (Baltimore) ; 103(24): e37963, 2024 Jun 14.
Article de Anglais | MEDLINE | ID: mdl-38875401

RÉSUMÉ

BACKGROUND: Graves' disease is a prevalent thyroid disorder and is the primary cause of hyperthyroidism. Significant progress has been made in understanding the epidemiology, pathogenesis, diagnosis, treatment, and prognosis of this disease. However, bibliometric analyses on Graves' disease are lacking. We aimed to comprehensively summarize the research, progression, and focal points of Graves' disease through data mining and integrated analysis of the existing literature. METHODS: We retrieved relevant literature on Graves' disease from 2003 to 2023 from the Web of Science database. We performed bibliometric analysis using CiteSpace and the R package Bibliometrix. RESULTS: We identified 10,901 publications from 132 countries, with a steady rise in the number of publications over the past 5 years. The US leads in publication volume, with the University of California System being the primary contributing institution. The journal Thyroid had the highest publication output, while the Journal of Clinical Endocrinology and Metabolism was the most frequently cited. These publications involved 2305 authors, with Antonelli Alessandro and Smith Terry being the most prolific. The most frequently cited articles were the "2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis" and the "Thyroid Association/European Group on Graves' orbitopathy guidelines for the management of Graves' orbitopathy." Analysis of the bursts of cited references, keywords, and their clustering revealed that research on Graves' disease predominantly centers on clinical management, thyroid-stimulating hormone receptors, thyroid hormones, autoimmunity and inflammation, Graves' ophthalmopathy, thyroid nodules, and thyroid cancer. CONCLUSION: This is the first comprehensive bibliometric study to summarize progress and trends in Graves' disease research. These results highlight recent research hotspots and promising directions, thereby providing a valuable reference for other scholars.


Sujet(s)
Bibliométrie , Maladie de Basedow , Humains , Maladie de Basedow/épidémiologie , Recherche biomédicale/tendances , Recherche biomédicale/statistiques et données numériques , Santé mondiale
10.
J Magn Reson ; 364: 107711, 2024 Jun 10.
Article de Anglais | MEDLINE | ID: mdl-38879928

RÉSUMÉ

In the design of ultrahigh field nuclear magnetic resonance (NMR) superconducting magnets, it typically requires a high homogeneous magnetic field in the diameter of spherical volume (DSV) to obtain high spectrum resolution. However, shimming technique presents challenges due to the magnet bore space limitations, as accurate measurement of magnetic field distribution is very difficult, especially for customized micro-bore magnets. In this study, we introduced an active shimming method that utilized iterative adjustment of shim coil currents to improve the magnetic field homogeneity based on the full width at half maximum (FWHM) of the spectrum. The proposed method can determine the optimal set of currents for shim coils, effectively enhancing spatial field homogeneity by converging the FWHM. Experimental validation on a 25 T NMR superconducting magnet demonstrated the efficacy of the proposed method. Specifically, the active shimming method improved the field homogeneity of a 10 mm DSV from 7.09 ppm to 2.27 ppm with only four shim coils, providing a superior magnetic field environment for solid NMR and further magnetic resonance imaging (MRI) experiment. Furthermore, the proposed method can be promoted to more customized micro-bore magnets that require high magnetic field homogeneity.

11.
J Hazard Mater ; 475: 134925, 2024 Jun 14.
Article de Anglais | MEDLINE | ID: mdl-38889458

RÉSUMÉ

The polychaete Perinereis aibuhitensis is used for bioremediation; however, its ability to remove fluorene, a common environmental pollutant, from sediments remains unclear, especially at low concentrations of fluorene (10 mg/kg). In this study, we explored the mechanism of intestinal injury induced by low concentrations of fluorene and the reason intestinal injury is alleviated in high fluorene concentration groups (100 and 1000 mg/kg) using histology, ecological biomarkers, gut microbiome, and metabolic response analyses. The results show that P. aibuhitensis showed high tolerance to fluorene in sediments, with clearance rates ranging 25-50 %. However, the remediation effect at low fluorene concentrations (10 mg/kg) was poor. This is attributed to promoting the growth of harmful microorganisms such as Microvirga, which can cause metabolic disorders, intestinal flora imbalances, and the generation of harmful substances such as 2-hydroxyfluorene. These can result in severe intestinal injury in P. aibuhitensis, reducing its fluorene clearance rate. However, high fluorene concentrations (100 and 1000 mg/kg) may promote the growth of beneficial microorganisms such as Faecalibacterium, which can replace the dominant harmful microorganisms and improve metabolism to reverse the intestinal injury caused by low fluorene concentrations, ultimately restoring the fluorene-removal ability of P. aibuhitensis. This study demonstrates an effective method for evaluating the potential ecological risks of fluorene pollution in marine sediments and provides guidance for using P. aibuhitensis for remediation.

12.
J Cell Mol Med ; 28(12): e18481, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38899542

RÉSUMÉ

Bacillus subtilis relies on biofilms for survival in harsh environments. Extracellular polymeric substance (EPS) is a crucial component of biofilms, yet the dynamics of EPS production in single cells remain elusive. To unveil the modulation of EPS synthesis, we built a minimal network model comprising the SinI-SinR-SlrR module, Spo0A, and EPS. Stochastic simulations revealed that antagonistic interplay between SinI and SinR enables EPS production in bursts. SlrR widens these bursts and increases their frequency by stabilizing SinR-SlrR complexes and depleting free SinR. DNA replication and chromosomal positioning of key genes dictate pulsatile changes in the slrR:sinR gene dosage ratio (gr) and Spo0A-P levels, each promoting EPS production in distinct phases of the cell cycle. As the cell cycle lengthens with nutrient stress, the duty cycle of gr pulsing decreases, whereas the amplitude of Spo0A-P pulses elevates. This coordinated response facilitates keeping a constant proportion of EPS-secreting cells within colonies across diverse nutrient conditions. Our results suggest that bacteria may 'encode' eps expression through strategic chromosomal organization. This work illuminates how stochastic protein interactions, gene copy number imbalance, and cell-cycle dynamics orchestrate EPS synthesis, offering a deeper understanding of biofilm formation.


Sujet(s)
Bacillus subtilis , Protéines bactériennes , Biofilms , Réplication de l'ADN , Régulation de l'expression des gènes bactériens , Biofilms/croissance et développement , Bacillus subtilis/génétique , Bacillus subtilis/métabolisme , Bacillus subtilis/physiologie , Réplication de l'ADN/génétique , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Matrice de substances polymériques extracellulaires/métabolisme , Cycle cellulaire/génétique
14.
Inorg Chem ; 63(25): 11832-11841, 2024 Jun 24.
Article de Anglais | MEDLINE | ID: mdl-38847596

RÉSUMÉ

Highly ordered periodic macroporous structures have been extensively utilized to significantly enhance the photocatalytic activity. However, constructing 3D interconnected ordered porous ternary nanostructures with highly crystalline frameworks remains a formidable challenge. Here, we introduce the design and fabrication of 3D interconnected periodic macroporous NaNbO3 (PM NaNbO3) to effectively increase the density of surface-active sites and optimize the photogenerated carrier-transfer efficiency. By incorporating Pt as a cocatalyst, PM NaNbO3 exhibits an exceptional photocatalytic hydrogen generation rate of 10.04 mmol h-1 g-1, which is approximately six and five times higher than those of calcined NaNbO3 (C-NaNbO3) and hydrothermal NaNbO3 (H-NaNbO3), respectively. This outstanding performance can be attributed to the synergistic effects arising from its well-interconnected pore architecture, large surface area, enhanced light absorption capability, and improved charge carrier separation and transport efficiency. The findings presented in this study demonstrate an innovative approach toward designing hierarchically periodic macroporous materials for solar-driven hydrogen production.

16.
Angew Chem Int Ed Engl ; : e202407355, 2024 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-38837587

RÉSUMÉ

The structure of molecular aggregates is crucial for charge transport and photovoltaic performance in organic solar cells (OSCs). Herein, the intermolecular interactions and aggregated structures of nonfused-ring electron acceptors (NFREAs) are precisely regulated through a halogen transposition strategy, resulting in a noteworthy transformation from a 2D-layered structure to a 3D-interconnected packing network. Based on the 3D electron transport pathway, the binary and ternary devices deliver outstanding power conversion efficiencies (PCEs) of 17.46% and 18.24%, respectively, marking the highest value for NFREA-based OSCs.

17.
Brain Res ; 1840: 149049, 2024 May 31.
Article de Anglais | MEDLINE | ID: mdl-38825161

RÉSUMÉ

BACKGROUND: Previous studies have revealed structural brain abnormalities in individuals with depression, but the causal relationship between depression and brain structure remains unclear. METHODS: A genetic correlation analysis was conducted using summary statistics from the largest genome-wide association studies for depression (N = 674,452) and 1,265 brain structural imaging-derived phenotypes (IDPs, N = 33,224). Subsequently, a bidirectional two-sample Mendelian Randomization (MR) approach was employed to explore the causal relationships between depression and the IDPs that showed genetic correlations with depression. The main MR results were obtained using the inverse variance weighted (IVW) method, and other MR methods were further employed to ensure the reliability of the findings. RESULTS: Ninety structural IDPs were identified as being genetically correlated with depression and were included in the MR analyses. The IVW MR results indicated that reductions in the volume of several brain regions, including the bilateral subcallosal cortex, right medial orbitofrontal cortex, and right middle-posterior part of the cingulate cortex, were causally linked to an increased risk of depression. Additionally, decreases in surface area of the right middle temporal visual area, right middle temporal cortex, right inferior temporal cortex, and right middle-posterior part of the cingulate cortex were causally associated with a heightened risk of depression. Validation and sensitivity analyses supported the robustness of these findings. However, no evidence was found for a causal effect of depression on structural IDPs. CONCLUSIONS: Our findings reveal the causal influence of specific brain structures on depression, providing evidence to consider brain structural changes in the etiology and treatment of depression.

19.
Heliyon ; 10(11): e31626, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38841475

RÉSUMÉ

Understanding public emotion on social media about community wellness is crucial for enhancing health awareness and guiding policy-making. In order to more fully mine the deep contextual semantical information of short texts and further enhance the effectiveness of emotion prediction in social media, we propose the Deep Parallel Contextual Analysis Framework (DPCAF) in the community wellness domain, specifically addressing the challenges of limited text length and available semantical features in social media text. Specifically, at the embedding layer, we first utilize two different word embedding techniques to generate high-quality vector representations, aiming to achieve more comprehensive semantical capture, stronger generalization ability, and more robust model performance. Subsequently, in the deep contextual layer, the obtained representations are fused with POS and locational representations, and processed through a deep parallel layer composed of Convolutional Neural Networks and Bidirectional Long Short-Term Memory Network. An attention model is then used to further extract semantical features of social media texts. Finally, these deep parallel contextual representations are post-integrated for emotion prediction. Experiments on a dataset collected from social media regarding community wellness demonstrate that compared to benchmark models, DPCAF achieves at least a 4.81 % increase in Precision, a 3.44 % increase in Recall, and a 10.81 % increase in F1-score. Relative to the most advanced models, DPCAF shows a minimum improvement of 2.65 % in Precision, 3.02 % in Recall, and 2.53 % in F1-score.

20.
J Colloid Interface Sci ; 672: 805-813, 2024 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-38875836

RÉSUMÉ

Short-side-chain perfluorosulfonic acid (SSC-PFSA) ionomers with high ion-exchange-capacity are promising candidates for high-temperature proton exchange membranes (PEMs) and catalyst layer (CL) binders. The solution-casting method determines the importance of SSC-PFSA dispersion characteristics in shaping the morphology of PEMs and CLs. Therefore, a thorough understanding of the chain behavior of SSC-PFSA in dispersions is essential for fabricating high-quality PEMs and CLs. In this study, we have employed multiple characterization techniques, including dynamic light scatting (DLS), small-angle X-ray scattering (SAXS), and cryo-transmission electron microscope (Cryo-TEM), to fully study the chain aggregation behaviors of SSC-PFSA in water-ethanol solvents and elucidate the concentration-dependent self-assembly process. In dilute dispersions (2 mg/mL), SSC-PFSA assembles into mono-disperse rod-like aggregates, featuring a twisted fluorocarbon backbone that forms a hydrophobic stem, and the sulfonic acid side chains extending outward to suit the hydrophilic environment. As the concentration increases, the radius of rod particles increases from 1.47 to 1.81 nm, and the mono-disperse rod particles first form a "end-to-end" configuration that doubles length (10 mg/mL), and then transform into a swollen network structure in semi-dilute dispersion (20 mg/mL). This work provides a well-established structure model for SSC-PFSA dispersions, which is the key nanostructure to be inherited by PEMs.

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