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1.
Sci Rep ; 14(1): 13995, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38886477

RESUMEN

As mechanized open-pit coal mining intensifies, assessing and predicting slope stability has become increasingly important. To address the limitations of traditional mechanical calculations, numerical simulations, and physical experiments, this paper identifies the key factors impacting slope stability in open-pit mines and develops a multi-parameter sample data set. The study employs hyperparameters optimized using a Bayesian algorithm, introduces additional convolutional layers, and combines the Adam optimizer with dropout techniques to enhance the feature extraction and performance of one-dimensional convolutional neural networks (1D-CNN). This leads to a Bayesian-optimized one-dimensional convolutional neural network (B-1D MCNN) model for predicting slope stability.The study evaluates the classification performance and accuracy of various models for slope stability, including BP neural networks, genetic algorithm-optimized convolutional neural networks, 1D-CNN, and B-1D MCNN, using accuracy, precision, and F1-score as metrics. The analysis also examines the influence of factor indicators and training set length on the model's output to assess its generalization capabilities.The research findings suggest that: (1) the B-1D MCNN model for evaluating slope stability demonstrates the capability to accurately depict the nonlinear correlation between influencing factors and slope stability. (2) Compared with other models, the B-1D MCNN model has shown enhancements of 10.96% to 27.85%, 10.26% to 28.55%, and 8.98% to 25.05% in terms of Accuracy, F1-Score, and Precision, respectively. (3) As the length of the training dataset increases, the performance of the model improves accordingly. (4) The B-1D MCNN model shows a generalization power of 87.5%.

3.
Mar Pollut Bull ; 203: 116493, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38759468

RESUMEN

The properties of microplastics determine their settling velocities and affect the fates and migration pathways of microplastics. This paper has simulated the settling velocities of film-shaped microplastics, which are present in natural aquatic environments. The numerical results provided more data to fit the terminal settling velocities of film-shaped microplastics. Comparison between the particle definition and the equivalent spherical diameter confirmed that the particle definition is more suitable for film-shaped microplastics. In the transitional flow regime, CD decreases linearly with Re. As Re further increases, CD gradually converges at approximately 1.20. By integrating the experimental and simulated data, a new explicit formula for predicting the settling velocity of film-shaped microplastics has been presented with the optimal shape parameter f. The presented formula achieves better performance (MAPE = 6.6 %, RMSE = 16.8 %, and R2 = 0.99) than the existing formulas for settling velocity for film-shaped microplastics, closely rivaling that of the ensemble learning algorithm.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos
4.
Sci Rep ; 14(1): 10119, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698057

RESUMEN

The production plan of an open-pit mine depends on the block model, so it's crucial to determine the appropriate method and size for partitioning it. This study proposes a new method based on a closed shell three-dimensional geological model for determining block model size in open-pit mines. Instead of using regular block models, the shell model is directly cut, and the discrete geological body is referred to as the "mining model." Mining parameters and the shovel-truck's performance are integrated into the method. Bench height determines the Z-axis size, bench slope angle determines the inclination angle, and shovel width determines the X-axis size of the block model. The operation efficiency of the shovel-truck considers the probability distribution of simultaneous operations, allowing the determination of the Y-axis size of block models for different types of shovels. The developed "Mining Model" module in the software "Life Cycle Mining System" is used for practical implementation. By comparing the results with traditional block models, the superiority of the proposed method is demonstrated. This study provides a more accurate model for optimizing the production plan of open-pit mines throughout their life cycle.

5.
Front Endocrinol (Lausanne) ; 15: 1253832, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686201

RESUMEN

Background: In recent years, with the widespread use of immune checkpoint inhibitors (ICIs) in cancer treatment, the toxicity associated with immunotherapy of ICIs has attracted more attention from scholars. Endocrine toxicity is the most likely immune-related adverse events (irAEs) and is often irreversible, posing a significant clinical treatment challenge. Methods: In this study, bibliometric methods were used to analyze relevant literature in screening endocrine-related adverse events caused by ICIs in the Web of Science core collection database (WoSCC) and to summarize the status, research hot spots, and future trends in this field. Results: 321 countries, 297 institutions, 365 authors, and 305 journals had published 671 English documents on endocrine adverse reactions of ICIs as of 1 December, 2022. The United States, Japan, and China were the top three countries with the most publications. The University of Texas MD Anderson Cancer Center, Harvard Medical School, and Memorial Sloan Kettering Cancer Center were the top three research institutions in terms of publication output. F Stephen Hodi, from the Dana-Farber Cancer Institute in the United States, contributed the largest number of publications. Frontiers in Oncology, which was the most widely distributed publication in the field. The main keywords or clusters identified that current research hotspots include the management of endocrine-related adverse events, hypophysitis, thyroid dysfunction, type I diabetes mellitus, and the impact of endocrine adverse events on survival of patients in this field. Conclusion: The basic knowledge structure of the field of endocrine-related adverse events of ICIs, including publication trends, authors, institutions, countries, keywords, journals and publications, and cited documents, was visually analyzed in this bibliometric analysis. The research results comprehensively demonstrated the hot spots and future trends in the research field, as well as its broad prospects, thus providing a reference for the researchers.


Asunto(s)
Bibliometría , Enfermedades del Sistema Endocrino , Inhibidores de Puntos de Control Inmunológico , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Enfermedades del Sistema Endocrino/inducido químicamente , Enfermedades del Sistema Endocrino/epidemiología , Neoplasias/tratamiento farmacológico , Inmunoterapia/efectos adversos , Investigación Biomédica/tendencias
6.
Cancer Immunol Res ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630891

RESUMEN

Follicular helper T (TFH) cells are essential for inducing germinal center (GC) reactions to mediate humoral adaptive immunity in tumors, but the mechanisms underlying TFH cell differentiation remain unclear. Here, we found that the metabolism sensor sirtuin 3 (SIRT3) is critical for TFH cell differentiation and GC formation during tumor and viral infection. SIRT3 deficiency in CD4+ T cells intrinsically enhanced TFH cell differentiation and GC reactions during tumor and virus infection. Mechanistically, damaged oxidative phosphorylation (OXPHOS) compensatively triggered the NAD+-glycolysis pathway to provide a cellular energy supply, which was necessary for SIRT3 deficiency-induced TFH cell differentiation. Blocking NAD+ synthesis-glycolysis signaling or recovering OXPHOS activities reversed the TFH cell differentiation induced by SIRT3 deficiency. Moreover, the mTOR and HIF1α signaling axis was found to be responsible for TFH cell differentiation induced by SIRT3 deficiency. HIF1α directly interacted with and regulated the activity of the transcription factor Bcl-6. Thus, our findings identify a cellular energy compensatory mechanism, regulated by the mitochondrial sensor SIRT3, that triggers NAD+-dependent glycolysis during mitochondrial OXPHOS injuries and a mTOR-HIF1α-Bcl-6 pathway to reprogram TFH cell differentiation. These data have implications for future cancer immunotherapy research targeting SIRT3 in T cells.

7.
Heliyon ; 10(6): e27832, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38515725

RESUMEN

Objective: The primary objective of this paper is to investigate the research hotspots and future trends of immune-related adverse events induced by immune checkpoint inhibitors, offering valuable insights for researchers in this field. Methodology: Using the visual analysis software, this study conducted quantitative statistics and visualization research on the relevant literature concerning immune-related adverse events caused by immune checkpoint inhibitors in the Web of Science Core Collection Database. By evaluating the publication trends, countries, institutions, keywords, research status, cited documents, and document co-citations, among several others, the discussion revolved around the hot spots and future development trends in this field and provided references for future research. Findings and conclusions: A total of 514 English articles were included, and the top three countries in the research field at the time of this study were the United States, Japan, and China. More specifically, the University of Texas MD Anderson Cancer Center, Dana-Farber Cancer Institute, and Massachusetts General Hospital have been the top three research institutes with more than 10 publications. The frequency of keyword use linked to immune-related adverse events caused by immune checkpoint inhibitors in literature research has been steadily growing over the years. Additionally, the research with respect to the disease focuses on melanoma, cell lung cancer, hepatocellular carcinoma, and breast cancer. In the context of drugs, cancer-related research has mainly focused on the combined use of nivolumab, pembrolizumab, ipilimumab, and immune checkpoint inhibitors. Meanwhile, research on adverse events has delved into the immune checkpoint inhibitors causing vitiligo, thyroid dysfunction, pancreatitis, cholangitis, and rheumatism. Related studies cover acute arthritis, myositis, acute kidney injury, as well as the combination therapy of immune checkpoint inhibitors and docetaxel, management of irAEs in cancer immunotherapy, and biomarkers of immune adverse reactions of immune checkpoint inhibitors. Finally, case report studies of immune adverse reactions caused by immune checkpoint inhibitors could serve as research hotspots in the future.

8.
PLoS One ; 19(2): e0296932, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38394262

RESUMEN

The delineation of the open-pit mining boundary, particularly in the context of medium to long-term planning, forms the foundation of mining design. However, due to the non-linear and dynamic nature of the economic and technical parameters influencing boundary delineation, determining the optimal mining boundary can be exceedingly challenging. Currently, most boundary optimization methods assume that block parameters remain fixed, which results in enterprises assuming a certain level of risk when facing changes in internal and external conditions. In this regard, this paper introduces the concept of "achievement degree" to reflect the risk associated with the results of boundary design. Using coal prices as an example, this article applies the predicted coal price curve to boundary optimization adjustments by specifying the "achievement degree" requirements for various time periods, thereby facilitating risk-controlled and economically optimal boundary decisions. Taking the illustrative case of an idealized small-scale inclined coal seam open-pit mine, adjustments to the boundary closely track variations in coal prices, further enhancing returns. The results demonstrate that the method proposed in this paper can increase overall revenue by approximately 51.15% within the forecast period, while effectively managing risks.


Asunto(s)
Minas de Carbón , Carbón Mineral , Minería , Medición de Riesgo , Gestión de Riesgos
9.
BMC Musculoskelet Disord ; 25(1): 184, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424580

RESUMEN

BACKGROUND: To evaluate the reliability of the Soft Tissue Tension Cloud Chart (STTCC) technology, an original method combining multi-point Cervical Paravertebral Soft Tissue Test (CPSTT) with MATLAB software, we conducted a preliminary analysis on the immediate effects of Orthopaedic Manual Therapy (OMT) on cervical paravertebral soft tissue. METHODS: 30 patients with Cervical Spondylotic Radiculopathy (CSR) were included in this study. We analyzed the differences in CPSTT before and after treatment with Cervical Rotation-Traction Manipulation (CRTM), a representative OMT technique in Traditional Chinese Medicine, using the STTCC technology. RESULTS: The STTCC results demonstrated that post-treatment CPSTT levels in CSR patients were significantly lower than pre-treatment levels after application of CRTM, with a statistically significant difference (P < 0.001). Additionally, pre-treatment CPSTT levels on the symptomatic side (with radicular pain or numbness) were higher across the C5 to C7 vertebrae compared to the asymptomatic side (without symptoms) (P < 0.001). However, this difference disappeared after CRTM treatment (P = 0.231). CONCLUSIONS: The STTCC technology represents a reliable method for analyzing the immediate effects of OMT. CSR patients display uneven distribution of CPSTT characterized by higher tension on the symptomatic side. CRTM not only reduces overall cervical soft tissue tension in CSR patients, but can also balance the asymmetrical tension between the symptomatic and asymptomatic sides. TRIAL REGISTRATION: This study was approved by the Chinese Clinical Trials Registry (Website: . https://www.chictr.org.cn .) on 20/04/2021 and the Registration Number is ChiCTR2100045648.


Asunto(s)
Manipulación Espinal , Radiculopatía , Espondilosis , Humanos , Rotación , Tracción/métodos , Reproducibilidad de los Resultados , Manipulación Espinal/métodos , Vértebras Cervicales , Radiculopatía/diagnóstico , Radiculopatía/terapia , Espondilosis/terapia , Tecnología
10.
Front Bioeng Biotechnol ; 12: 1322212, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38390357

RESUMEN

Objective: Evaluate the effect of rotation-traction manipulation on intradiskal pressure in human cervical spine specimen with different force and duration parameters, and compare the intradiskal pressure changes between rotation-traction manipulation and traction. Methods: Seven human cervical spine specimens were included in this study. The intradiskal pressure was measured by miniature pressure sensor implanting in the nucleus pulposus. rotation-traction manipulation and cervical spine traction were simulated using the MTS biomechanical machine. Varied thrust forces (50N, 150N, and 250N) and durations (0.05 s, 0.1 s, and 0.15 s) were applied during rotation-traction manipulation with Intradiscal pressure recorded in the neutral position, rotation-anteflexion position, preloading, and thrusting phases. Futuremore, we documented changes in intradiscal pressure during cervical spine traction with different loading forces (50N, 150N, and 250N). And a comparative analysis was performed to discern the impact on intradiscal pressure between manipulation and traction. Results: Manipulation application induced a significant reduction in intradiscal pressure during preloading and thrusting phases for each cervical intervertebral disc (p < 0.05). When adjusting thrust parameters, a discernible decrease in intradiscal pressure was observed with increasing thrust force, and the variations between different thrust forces were statistically significant (p < 0.05). Conversely, changes in duration did not yield a significant impact on intradiscal pressure (p > 0.05). Additionally, after traction with varying loading forces (50N, 150N, 250N), a noteworthy decrease in intradiscal pressure was observed (p < 0.05). And a comparative analysis revealed that rotation-traction manipulation more markedly reduced intradiscal pressure compared to traction alone (p < 0.05). Conclusion: Both rotation-traction manipulation and cervical spine traction can reduce intradiscal pressure, exhibiting a positive correlation with force. Notably, manipulation elicits more pronounced and immediate decompression effect, contributing a potential biomechanical rationale for its therapeutic efficacy.

11.
PLoS One ; 19(1): e0295579, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38165924

RESUMEN

This paper proposes a feature selection method based on a hybrid optimization algorithm that combines the Golden Jackal Optimization (GJO) and Grey Wolf Optimizer (GWO). The primary objective of this method is to create an effective data dimensionality reduction technique for eliminating redundant, irrelevant, and noisy features within high-dimensional datasets. Drawing inspiration from the Chinese idiom "Chai Lang Hu Bao," hybrid algorithm mechanisms, and cooperative behaviors observed in natural animal populations, we amalgamate the GWO algorithm, the Lagrange interpolation method, and the GJO algorithm to propose the multi-strategy fusion GJO-GWO algorithm. In Case 1, the GJO-GWO algorithm addressed eight complex benchmark functions. In Case 2, GJO-GWO was utilized to tackle ten feature selection problems. Experimental results consistently demonstrate that under identical experimental conditions, whether solving complex benchmark functions or addressing feature selection problems, GJO-GWO exhibits smaller means, lower standard deviations, higher classification accuracy, and reduced execution times. These findings affirm the superior optimization performance, classification accuracy, and stability of the GJO-GWO algorithm.

12.
Int J Cancer ; 154(5): 773-785, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37815294

RESUMEN

Neutrophil extracellular trap (NET) is one of the defense functions of neutrophils, which has a rapid ability to kill infections and is also crucial in a variety of immune-associated diseases including infections, tumors and autoimmune diseases. Recent studies have shown that NETs are closely related to the development of tumors. The regulatory role of NETs in tumors has been of interest to researchers. In addition to awakening latent tumor cells, NETs can also promote the proliferation and development of tumor cells and their metastasis to other sites. At the same time, NETs also have the effect of inhibiting tumors. At present, there are some new advances in the impact of NETs on tumor development, which will provide a more theoretical basis for developing NET-targeted drugs. Therefore, this review just summarized the formation process of NETs, the regulation of tumor development and the treatment methods based on NETs.


Asunto(s)
Enfermedades Autoinmunes , Trampas Extracelulares , Neoplasias , Humanos , Neutrófilos , Neoplasias/patología
13.
Gene ; 893: 147948, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37925117

RESUMEN

Cathepsin C (CTSC) has been reported to be upregulated in several cancers, however, there are still many missing links about the role of CTSC in glioma. To address this knowledge gap, the present study employed bioinformatics analysis, Transwell assay, RT-qPCR and Western blot assays to investigate the expression level of CTSC in glioma tissues, its relationship with survival period, and its effect on the migration and invasion ability of glioma cells. The findings revealed that CTSC was upregulated in glioma and was associated with poor prognosis. Moreover, CTSC was found to promote cell migration and invasion abilities as well as epithelial-mesenchymal transition (EMT). A further study found that CTSC induced SERPINA3 and STAT3 expression in glioma cells. Additionally, we demonstrated that STAT3 signaling mediated upregulation of SERPINA3 expression by CTSC. In sum, our findings suggest that CTSC activates the STAT3/SERPINA3 axis to promote migration and invasion of glioma cells, which may lead to new potential therapeutic approaches for humans with cancer.


Asunto(s)
Glioma , Serpinas , Humanos , Catepsina C/metabolismo , Línea Celular Tumoral , Transducción de Señal , Glioma/genética , Glioma/metabolismo , Movimiento Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Proliferación Celular , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Serpinas/metabolismo
14.
Arch Microbiol ; 206(1): 18, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085370

RESUMEN

Through the study of biosorption of Pb2+ by lactic acid bacteria, two strains called CN-011 and CN-005 with high tolerance and great adsorption to lead were screened. The minimum bactericidal concentration of lead ions for both CN-011 and CN-005 was 1.45 mmol/L. The optimal culture conditions for the removal of 30 mg/L lead ions were achieved by culturing lactic acid bacteria at an initial pH of 7.0, 37 °C and 120 rpm for 48 h. The adsorption rate of CN-011 and CN-005 for Pb2+ were 85.95% and 86.78%, respectively. In simulated wastewater samples, the average adsorption rate of Pb2+ was 73.38% for CN-011 and 74.15% for CN-005. The mechanism of biosorption was characterized by Fourier Transform infrared spectroscopy, Scanning Electron Microscope-Energy Dispersive Spectrometer, X-ray Photoelectron Spectroscopy, which revealed that Pb2+ mainly reacted with hydroxyl ions in peptidoglycan or polysaccharide, and carboxylate radical in teichoic acid or protein on the surface of lactic acid bacteria cell wall. The deposits produced on the bacterial surface were identified as lead oxide and lead nitrate.


Asunto(s)
Lactobacillales , Contaminantes Químicos del Agua , Aguas Residuales , Lactobacillales/metabolismo , Plomo/metabolismo , Concentración de Iones de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Iones/metabolismo , Cinética , Contaminantes Químicos del Agua/análisis , Biomasa
15.
Sci Rep ; 13(1): 21286, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38042905

RESUMEN

To address the problem of excessive local secondary stripping between adjacent mining areas in open pit mines caused by internal row raising, a multivariate function was fitted to the model of the main mining seam of Zhundong open pit coal mine in Xinjiang, and the different locations of the end gang of the second mining area were divided into multiple sections at certain step sizes and calculated by integration, resulting in stripping ratios for each section, which were fitted to a stripping ratio curve. The optimal location of the mining area boundary was found to be 55 m westward offset from the mining area boundary in the inner row of the raised section, and numerical simulations based on the strength reduction method were applied to analyse the slope stability of the end gang at this location. The results of the study show that the analysed slope meets the stability requirements and the optimised new boundary avoids the stripping of approximately 65,837,376 m3 of economically unreasonable section.

16.
Heliyon ; 9(10): e20142, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37780780

RESUMEN

Objective: To discuss the hotspots and future trends of autophagy in traditional Chinese medicine (TCM) and provide a reference for researchers in this field. Method: Using visual analysis tools, metrological statistics and visual research on the pertinent literature in the area of autophagy use in TCM were undertaken in the core collection database of the Web of Science. By examining the authors, keywords, research circumstances, research hotspots, and trends of linked research, the use of autophagy in TCM was investigated. Results and Conclusions: A total of 916 studies were included, among which Beijing University Chinese Medicine was the largest number of advantageous research institutions, followed by Shanghai University Traditional Chinese Medicine and Guangzhou University Chinese Medicine.The keywords of literature research primarily comprise apoptosis, activation, inhibition, pathway, mechanism, oxidative stress, proliferation, NF-κB, cancer, mtor, etc. At present, the research on autophagy in the field of TCM is increasing on a year-to-year basis. The research has focused on the role played by TCM in malignant tumors, atherosclerosis, Alzheimer's disease through autophagy, and the regulation of autophagy signaling pathways (e.g., PI3K/AKT/mTOR signaling pathway, TLR4 signaling pathway,nrf2 signaling pathway and NF-κB signaling pathway). In the future, the therapeutic effect of TCM on chemotherapy-resistant tumor cells through autophagy pathway, the role of TCM mediating mitophagy and activating autophagy function, and the therapeutic effect of TCM components represented by luteolin on tumors, asthma, myocardial injury and other diseases through autophagy mechanism will be the research hotspots in the future.

17.
Sci Rep ; 13(1): 18580, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903870

RESUMEN

The transport truck is one of the important equipment for open-pit mines, and predicting the truck's fault time is of great significance in improving the economic benefits of open-pit mines. In this paper, we discuss the reason for the large prediction error of the exponential smoothing method. Then, we propose a novel nonlinear exponential smoothing method (ESNN) for predicting the truck's fault time, and demonstrate the equivalence between our approach and the neural network structure. Finally, based on the augmented Lagrange function, the solving method of ESNN is proposed. We conduct experiments on real-world datasets and our results demonstrate the effectiveness of ESNN in comparison to existing state-of-the-art methods. Our approach makes it easier for maintenance personnel to predict fault situations in advance and provides a basis for enterprises to develop preventive maintenance plans.

18.
J Phys Ther Sci ; 35(9): 628-632, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37670764

RESUMEN

[Purpose] To measure the reliability of and quantify the force on the spinous process during lumbar neuromuscular joint facilitation using mechanical measuring gloves. [Participants and Methods] We recruited 12 healthy participants. The operator wore a mechanical measuring glove and performed evaluations in the four modes of neuromuscular joint facilitation of the lumbar spine. The mechanical glove was used to measure the force applied by the fingers on the spinous process during the intervention. [Results] The reliability of measuring the supraspinous force during lumbar neuromuscular joint facilitation with mechanical gloves was found to be good; the force was 30.9 ± 6.6 N for front lifting, 37.1 ± 9.1 N for rear descent, 36.8 ± 9.0 N for forward descent, and 24.6 ± 4.7 N for rear lifting. Overall, the average force was 32.3 ± 9.0 N. No statistical difference was observed between passive and resistance motion. [Conclusion] This study confirmed that the measurement of the force on the spinous process in lumbar neuromuscular joint facilitation using mechanical measurement gloves has good reliability. Furthermore, we determined the average force exerted on the spinous process during lumbar neuromuscular joint facilitation and quantified the operation specifications of this manipulation were.

19.
Mar Pollut Bull ; 194(Pt B): 115438, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37659321

RESUMEN

The settling process of marine microplastics (MPs) is crucial research concerning the transport and movement of MPs. The settling processes of MP fibers that possess a cylindrical geometry are affected by environmental factors and properties. In this study, a three-dimensional numerical model for the still water settling of MPs with complex shapes was constructed using the lattice Boltzmann method (LBM) and the immersed boundary method (IBM). The fully resolved settling simulation of cylindrical MPs was achieved, and the model results demonstrated good agreement with the semi-empirical settling velocity formulas. Based on the simulation results, the critical aspect ratio of the cylindrical MP was found to be between 0.93 and 0.94. Near this critical aspect ratio, there is a decline in the drag force. Additionally, it was found that the angular displacement and aspect ratio influence horizontal movement but not the vertical settling velocity, while the density only affects vertical movement.


Asunto(s)
Microplásticos , Plásticos , Simulación por Computador , Movimiento
20.
Am J Transplant ; 23(12): 1845-1857, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37633450

RESUMEN

Although myeloid-derived suppressor cells (MDSCs) are critical for allograft survival, their regulatory mechanism remains unclear. Herein, our results showed that metabolism sensor sirtuin 2 (SIRT2) negatively regulates the functions of MDSCs in inducing allogeneic skin graft rejection. Genetic deletion of SIRT2 in myeloid cells (Sirt2Δmye) increased the number of CD11b+Gr1+ MDSCs in bone marrow, spleens, draining lymph nodes, and allografts, inhibited the production of proinflammatory cytokine tumor necrosis factor ɑ, enhanced the production of anti-inflammatory cytokine interleukin 10, and potentiated the suppressive activation of MDSCs in prolonging allograft skin survival. C-X-C motif chemokine receptor 2 is critical for mediating the recruitment and cytokine production of MDSCs induced by SIRT2. Mechanistically, Sirt2Δmye enhanced NAD+ levels, succinate dehydrogenase subunit A (SDHA) activities, and oxidative phosphorylation (OXPHOS) levels in MDSCs after transplantation. Pharmacologically blocking nicotinamide phosphoribosyltransferase effectively reverses the production of cytokines and suppressive activities of MDSC induced by Sirt2Δmye. Blocking OXPHOS with knockdown of SDHA or pharmacological blocking of SDHA significantly restores Sirt2Δmye-mediated stronger MDSC suppressive activity and inflammatory factor productions. Thus, our findings identify a previously unrecognized interplay between NAD+ and SDH-mediated OXPHOS metabolic pathways in regulating MDSC functions induced by the metabolic sensor SIRT2 in allogeneic transplantation.


Asunto(s)
Células Supresoras de Origen Mieloide , Animales , Ratones , Sirtuina 2/metabolismo , Sirtuina 2/farmacología , NAD/metabolismo , NAD/farmacología , Trasplante Homólogo , Citocinas/metabolismo , Aloinjertos , Ratones Endogámicos C57BL
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