Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Inflamm Res ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112648

RESUMO

BACKGROUND: Acute Kidney Injury (AKI), a prevalent complication of Liver Transplantation (LT) that occurs during the perioperative period has been established to profoundly impact the prognosis of transplant recipients. This study aimed to investigate the mechanism of the hepatic IRI-induced AKI and to identify potential therapeutic targets for treating this condition and improving the prognosis of LT patients. METHODS: An integrated transcriptomics and proteomics approach was employed to investigate transcriptional and proteomic alterations in hepatic IRI-induced AKI and the hypoxia-reoxygenation (H/R) model using TCMK-1 cells and the hepatic IRI-induced AKI mouse model using male C57BL/6 J mice were employed to elucidate the underlying mechanisms. Hematoxylin-eosin staining, reverse transcription quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and Western blot were used to assess the effect of Rosiglitazone (RGZ) on hepatic IRI-induced AKI in vitro and in vivo. RESULTS: According to the results, 322 genes and 128 proteins were differentially expressed between the sham and AKI groups. Furthermore, Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomics (KEGG) pathway analyses revealed significant enrichment in pathways related to amino acid and lipid metabolism. Additionally, the Protein-Protein Interaction (PPI) network analysis of the kidney tissues obtained from a hepatic IRI-induced AKI mouse model highlighted arachidonic acid metabolism as the most prominent pathway. Animal and cellular analyses further revealed that RGZ, a PPAR-γ agonist, could inhibit the expression of the PPAR-γ/NF-κB signaling pathway-associated proteins in in vitro and in vivo. CONCLUSIONS: These findings collectively suggest that RGZ ameliorates hepatic IRI-induced AKI via PPAR-γ/NF-κB signaling pathway modulation, highlighting PPAR-γ as a crucial therapeutic target for AKI prevention post-LT.

2.
Environ Sci Technol ; 58(26): 11727-11736, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38836508

RESUMO

Satellite evidence indicates a global increase in lacustrine algal blooms. These blooms can drift with winds, resulting in significant changes of the algal biomass spatial distribution, which is crucial in bloom formation. However, the lack of long-term, large-scale observational data has limited our understanding of bloom drift. Here, we have developed a novel method to track the drift using multi-source remote sensing satellites and presented a comprehensive bloom drift data set for four typical lakes: Lake Taihu (China, 2011-2021), Lake Chaohu (China, 2011-2020), Lake Dianchi (China, 2003-2021), and Lake Erie (North America, 2003-2021). We found that blooms closer to the water surface tend to drift faster. Higher temperatures and lower wind speeds bring blooms closer to the water surface, therefore accelerating drift and increasing biomass transportation. Under ongoing climate change, algal blooms are increasingly likely to spread over larger areas and accumulate in downwind waters, thereby posing a heightened risk to water resources. Our research greatly improves the understanding of algal bloom dynamics and provides new insights into the driving factors behind the global expansion of algal blooms. Our bloom-drift-tracking methodology also paves the way for the development of high-precision algal bloom prediction models.


Assuntos
Mudança Climática , Eutrofização , Lagos , Monitoramento Ambiental/métodos , Vento , Biomassa , China , Tecnologia de Sensoriamento Remoto
3.
Environ Res ; 238(Pt 2): 117265, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37775009

RESUMO

Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO2(110) surface. Specifically, the effects of doping MnO2 with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO2(110) surface includes O2 adsorption and dissociation, HCHO adsorption and dehydrogenation, CO2 desorption, H2O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol-1. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO2 outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO2 can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.


Assuntos
Manganês , Óxidos , Óxidos/química , Compostos de Manganês/química , Oxigênio/química , Catálise , Formaldeído/química
4.
Nucleic Acids Res ; 49(1): 190-205, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33332564

RESUMO

Secondary wall thickening in the sclerenchyma cells is strictly controlled by a complex network of transcription factors in vascular plants. However, little is known about the epigenetic mechanism regulating secondary wall biosynthesis. In this study, we identified that ARABIDOPSIS HOMOLOG of TRITHORAX1 (ATX1), a H3K4-histone methyltransferase, mediates the regulation of fiber cell wall development in inflorescence stems of Arabidopsis thaliana. Genome-wide analysis revealed that the up-regulation of genes involved in secondary wall formation during stem development is largely coordinated by increasing level of H3K4 tri-methylation. Among all histone methyltransferases for H3K4me3 in Arabidopsis, ATX1 is markedly increased during the inflorescence stem development and loss-of-function mutant atx1 was impaired in secondary wall thickening in interfascicular fibers. Genetic analysis showed that ATX1 positively regulates secondary wall deposition through activating the expression of secondary wall NAC master switch genes, SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN1 (SND1) and NAC SECONDARY WALL THICKENING PROMOTING FACTOR1 (NST1). We further identified that ATX1 directly binds the loci of SND1 and NST1, and activates their expression by increasing H3K4me3 levels at these loci. Taken together, our results reveal that ATX1 plays a key role in the regulation of secondary wall biosynthesis in interfascicular fibers during inflorescence stem development of Arabidopsis.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Código das Histonas , Histona-Lisina N-Metiltransferase/fisiologia , Histonas/genética , Inflorescência/metabolismo , Proteínas de Plantas/genética , Caules de Planta/metabolismo , Fatores de Transcrição/fisiologia , Transcriptoma , Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/genética , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica de Plantas/genética , Ontologia Genética , Genes de Plantas , Histonas/metabolismo , Lignina/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/ultraestrutura , RNA de Plantas/biossíntese , RNA de Plantas/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Xilanos/metabolismo
5.
Molecules ; 28(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049746

RESUMO

As a substitute for banned brominated flame retardants (BFRs), the use of organophosphate esters (OPEs) increased year by year with the increase in industrial production and living demand. It was inevitable that OPEs would be discharged into wastewater in excess, which posed a great threat to the health of human beings and aquatic organisms. In the past few decades, people used various methods to remove refractory OPEs. This paper reviewed the photocatalysis method, the adsorption method with wide applicability, and the biological method mainly relying on enzymolysis and hydrolysis to degrade OPEs in water. All three of these methods had the advantages of high removal efficiency and environmental protection for various organic pollutants. The degradation efficiency of OPEs, degradation mechanisms, and conversion products of OPEs by three methods were discussed and summarized. Finally, the development prospects and challenges of OPEs' degradation technology were discussed.


Assuntos
Retardadores de Chama , Água , Humanos , Retardadores de Chama/análise , Adsorção , Organofosfatos , Ésteres , Monitoramento Ambiental , China
6.
Angew Chem Int Ed Engl ; 62(52): e202315076, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37960950

RESUMO

Polymer electrolytes provide a visible pathway for the construction of high-safety quasi-solid-state batteries due to their high interface compatibility and processability. Nevertheless, sluggish ion transfer at room temperature seriously limits their applications. Herein, a triangular synergy strategy is proposed to accelerate Na-ion conduction via the cooperation of polymer-salt, ionic liquid, and electron-rich additive. Especially, PVDF-HFP and NaTFSI salt acted as the framework to stably accommodate all the ingredients. An ionic liquid (Emim+ -FSI- ) softened the polymer chains through a weakening molecule force and offered additional liquid pathways for ion transport. Physicochemical characterizations and theoretical calculations demonstrated that electron-rich Nerolin with π-cation interaction facilitated the dissociation of NaTFSI and effectively restrained the competitive migration of large cations from EmimFSI, thus lowering the energy barrier for ion transport. The strategy resulted in a thin F-rich interphase dominated by NaTFSI salt's decomposition, enabling rapid Na+ transmission across the interface. These combined effects resulted in a polymer electrolyte with high ionic conductivity (1.37×10-3  S cm-1 ) and tNa+ (0.79) at 25 °C. The assembled cells delivered reliable rate capability and stability (200 cycles, 99.2 %, 0.5 C) with a good safety performance.

7.
Plant J ; 96(6): 1121-1136, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30218582

RESUMO

Anthocyanins are involved in several aspects of development and defence in poplar (Populus spp.). Although, over the past decades, significant progress has been made in uncovering these anthocyanin biosynthetic and regulatory mechanisms, the fundamental understanding of the epigenetic regulation in this pathway is still largely unclear. Here, we isolated a histone H3K9 demethylase gene JMJ25 from Populus and characterized its role in anthocyanin biosynthesis by genetic and biochemical approaches. JMJ25 was induced by continuous dark treatment. Overexpression of JMJ25 led to downregulated expression of anthocyanin biosynthetic genes in transgenic poplar, resulting in a significant reduction in anthocyanin content. ChIP-qPCR assays showed that JMJ25 could directly associate with MYB182 chromatin and dynamically demethylate at H3K9me2. Furthermore, JMJ25 also affected the DNA methylation levels of MYB182. By contrast, knockout of JMJ25 by CRISPR/Cas9 resulted in ectopic anthocyanin accumulation under dark condition and increased expression of anthocyanin biosynthetic genes. Our results support a model in which JMJ25 directly affects MYB182 expression by altering the histone methylation status of its chromatin and DNA methylation, resulting in repression of anthocyanin accumulation. This study uncovered an epigenetic mechanism that modulates anthocyanin biosynthesis in poplar.


Assuntos
Antocianinas/biossíntese , Histona Desmetilases/metabolismo , Proteínas de Plantas/metabolismo , Populus/metabolismo , Cromatina/metabolismo , Metilação de DNA , Regulação da Expressão Gênica de Plantas/genética , Histona Desmetilases/genética , Histona Desmetilases/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Populus/enzimologia , Populus/genética
8.
Sensors (Basel) ; 15(11): 27525-42, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26528977

RESUMO

The regional constellation of the BeiDou navigation satellite system (BDS) has been providing continuous positioning, navigation and timing services since 27 December 2012, covering China and the surrounding area. Real-time kinematic (RTK) positioning with combined BDS and GPS observations is feasible. Besides, all satellites of BDS can transmit triple-frequency signals. Using the advantages of multi-pseudorange and carrier observations from multi-systems and multi-frequencies is expected to be of much benefit for ambiguity resolution (AR). We propose an integrated AR strategy for medium baselines by using the combined GPS and BDS dual/triple-frequency observations. In the method, firstly the extra-wide-lane (EWL) ambiguities of triple-frequency system, i.e., BDS, are determined first. Then the dual-frequency WL ambiguities of BDS and GPS were resolved with the geometry-based model by using the BDS ambiguity-fixed EWL observations. After that, basic (i.e., L1/L2 or B1/B2) ambiguities of BDS and GPS are estimated together with the so-called ionosphere-constrained model, where the ambiguity-fixed WL observations are added to enhance the model strength. During both of the WL and basic AR, a partial ambiguity fixing (PAF) strategy is adopted to weaken the negative influence of new-rising or low-elevation satellites. Experiments were conducted and presented, in which the GPS/BDS dual/triple-frequency data were collected in Nanjing and Zhengzhou of China, with the baseline distance varying from about 28.6 to 51.9 km. The results indicate that, compared to the single triple-frequency BDS system, the combined system can significantly enhance the AR model strength, and thus improve AR performance for medium baselines with a 75.7% reduction of initialization time on average. Besides, more accurate and stable positioning results can also be derived by using the combined GPS/BDS system.

9.
Environ Sci Pollut Res Int ; 31(10): 15209-15222, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38289558

RESUMO

Utilizing cost-effective corn cob, zinc chloride-modified biochar was synthesized through one-step method for benzene adsorption from air. Study on impregnation ratio impact showed optimal benzene adsorption at ZnCl2:CC ratio of 1.5:1, with capacity reaching 170.53 mg g-1. Characterization using BET, SEM, FTIR, and XPS was conducted. BET results indicated specific surface area of Zn1.5BC at 1260.63 m2 g-1 and maximum pore volume of 0.546 m3 g-1. SEM analysis revealed microporous-mesoporous structure in Zn1.5BC, marking significant improvement over original biomass. DFT pore size distribution and FTIR analysis suggested post-modification dehydration and elimination reactions, leading to volatile compound release, functional group reduction, and pore widening. XPS analysis showed decrease in O = C-OH content with increased impregnation ratio, enhancing biochar's π-π electron diffusion for benzene. Langmuir isotherm and pseudo-second-order kinetic models effectively described experimental data, indicating multilayer benzene adsorption on biochar controlled by complex physicochemical adsorption and pore diffusion. Adsorption condition assessment, including adsorption temperature (20-120 â„ƒ) and benzene concentration in inlet phase (159.73-383.36 mg L-1), was performed. Yoon-Nelson model fitting indicated adsorption site loss at higher temperatures and reduced capture ability due to increased adsorbate molecule kinetic energy. Higher adsorbate concentrations aided adsorption molecule diffusion to biochar surface and internal pores, increasing adsorption rate and shortening equilibrium time. Overall, zinc chloride-modified biochar facilitates benzene adsorption through pore filling and π-π interactions, with pore filling as primary mechanism. Produced biochar shows excellent regeneration properties and reusability.


Assuntos
Benzeno , Cloretos , Poluentes Químicos da Água , Compostos de Zinco , Zea mays , Adsorção , Poluentes Químicos da Água/química , Carvão Vegetal/química , Cinética
10.
J Exp Clin Cancer Res ; 43(1): 143, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745179

RESUMO

BACKGROUND: Sorafenib is a standard first-line treatment for advanced hepatocellular carcinoma (HCC), yet its effectiveness is often constrained. Emerging studies reveal that sorafenib triggers ferroptosis, an iron-dependent regulated cell death (RCD) mechanism characterized by lipid peroxidation. Our findings isolate the principal target responsible for ferroptosis in HCC cells and outline an approach to potentially augment sorafenib's therapeutic impact on HCC. METHODS: We investigated the gene expression alterations following sgRNA-mediated knockdown induced by erastin and sorafenib in HCC cells using CRISPR screening-based bioinformatics analysis. Gene set enrichment analysis (GSEA) and the "GDCRNATools" package facilitated the correlation studies. We employed tissue microarrays and cDNA microarrays for validation. Ubiquitination assay, Chromatin immunoprecipitation (ChIP) assay, RNA immunoprecipitation (RIP) assay, and dual-luciferase reporter assay were utilized to delineate the specific mechanisms underlying ferroptosis in HCC cells. RESULTS: Our study has revealed that pleiomorphic adenoma gene 1 (PLAG1), a gene implicated in pleomorphic adenoma, confers resistance to ferroptosis in HCC cells treated with sorafenib. Sorafenib leads to the opposite trend of protein and mRNA levels of PLAG1, which is not caused by affecting the stability or ubiquitination of PLAG1 protein, but by the regulation of PLAG1 at the transcriptional level by its upstream competitive endogenous long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1). Data from 139 HCC patients showed a significant positive correlation between PLAG1 and GPX4 levels in tumor samples, and PLAG1 is instrumental in redox homeostasis by driving the expression of glutathione peroxidase 4 (GPX4), the enzyme that reduces lipid peroxides (LPOs), which further leads to ferroptosis inhibition. CONCLUSIONS: Ferroptosis is a promising target for cancer therapy, especially for patients resistant to standard chemotherapy or immunotherapy. Our findings indicate that PLAG1 holds therapeutic promise and may enhance the efficacy of sorafenib in treating HCC.


Assuntos
Carcinoma Hepatocelular , Proteínas de Ligação a DNA , Ferroptose , Neoplasias Hepáticas , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Sorafenibe , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Ferroptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
Psychol Health ; : 1-20, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119793

RESUMO

OBJECTIVE: Health-promoting behaviors carry substantial significance for miners' overall health and well-being. This study aimed to examine the association between cumulative risk (CR) and miners' health-promoting behaviors and test the mediating role of health beliefs in this relationship. METHODS: Data were collected from a sequential survey conducted among 712 frontline miners (Mage=41.7 ± 10.1 years) in China. The survey entailed online questionnaire measurements at three distinct time points, each spaced two weeks apart. This study utilized the conceptual model of health-promoting behaviors, the CR model, and structural equation modeling in the analysis of relationships. RESULTS: CR was negatively related to health-promoting behaviors, with a negative acceleration effect. CR was positively associated with perceived threat in a gradient effect, while negatively associated with perceived benefits in a gradient effect. Furthermore, CR was negatively related to self-efficacy, following a negative acceleration effect. Perceived threat, perceived benefits, and self-efficacy emerged as significant mediators in the relationship between CR and health-promoting behaviors. CONCLUSION: This study highlights the critical role of considering both CR and health beliefs in shaping miners' health-promoting behaviors. Understanding these dynamics is pivotal for developing interventions to enhance miners' health and well-being.

12.
Materials (Basel) ; 17(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38541510

RESUMO

Thermally induced pores (TIPs) are generally the source of fatigue crack initiation in the powder metallurgy (PM) Ni-based FGH96 superalloy. The effect of TIPs on fatigue crack initiation on the surface of the FGH96 superalloy was detected using scanning electron microscopy (SEM). The cause of fatigue crack deflection was studied using electron backscatter diffraction (EBSD) analysis. The results indicated that there are two states of TIPs including isolated TIPs and clustered TIPs located at the grain boundary. The investigation of crack initiation and propagation around TIPs was conducted in detail through the comprehensive integration of experimental findings and computational results. For cracks initiated by isolated TIPs, the maximum equivalent size and the ratio of the vertical-parallel axis to the loading direction of the TIPs reveal a linear relationship, and both of them determine crack initiation. Regarding clustered TIPs, the constituent pores of the clustered TIPs will compete to initiate cracks based on the experimental results, and the largest pore will be more likely to initiate cracking. Moreover, the results showed that fatigue crack propagation can be hindered by hard-orientation grains and twins with a low Schmid factor (SF). Large-angle crack deflection due to twins with a low SF can significantly increase crack length and resistance to crack propagation.

13.
Materials (Basel) ; 17(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38930160

RESUMO

P91 steel and P91 steel joints experience performance degradation after serving for 30,000 h in working conditions. To clarify the damage and failure behavior and remaining life of the joints during subsequent service, further creep testing was conducted on the welded joints of P91 steel that had been in service for 30,000 h at three temperatures: 550 °C, 575 °C, and 600 °C. The fracture surface and the cross-section damage behavior were characterized by SEM and EBSD methods. The results show that there are two types of fracture modes in the joints at different temperatures: ductile cracking occurring at the BM, and type IV cracking occurring in the FGHAZ. The threshold stress for fracture mode transition decreases with an increase in working temperature. Type IV cracking near the HAZ is the main reason for the premature failure of joints during service. And based on the fracture mode, the dual-constant L-M method was proposed to predict the strength of in-service joint materials. The testing data are discussed and classified based on the fracture mode in this method, which has high accuracy and can prevent the premature failure of joints.

14.
Front Pediatr ; 12: 1305456, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38742242

RESUMO

Objective: The aim of this study was to identify the risk factors for postoperative adverse events in children with duplex kidney undergoing upper pole heminephrectomy. Methods: We collected clinical data from pediatric patients with duplex kidney who underwent upper pole heminephrectomy. Based on the presence or absence of postoperative adverse events, the patients were divided into two groups: an adverse events group (n = 16) and a non- adverse events group (n = 37), using multivariate logistic regression analysis to screen for independent risk factors for postoperative adverse events. Results: Through univariate and multivariate analysis, we found that the presence of upper renal ureterocele (P = 0.042, OR = 7.116, 95% CI 1.073-47.172), as well as the presence of accessory renal artery type (P = 0.016, OR = 10.639, 95% CI 1.551-72.978) and other types (P = 0.039, OR = 3.644, 95% CI 0.351-37.836) as the upper kidney's blood supply artery increase the risk of postoperative adverse events, with these differences being statistically significant. Conclusions: In pediatric patients with duplex kidney undergoing upper pole heminephrectomy, the presence of upper renal ureterocele and the presence of accessory renal artery type and other types as the upper kidney's blood supply artery are independent risk factors for postoperative adverse events.

15.
Environ Sci Pollut Res Int ; 30(2): 2555-2574, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35933530

RESUMO

In this paper, the NO-SCO (the selective catalytic oxidation of NO) experiments of single-phase Mn2O3, supported Mn2O3/Al2O3, and the Ce-doped MnxCey/Al catalyst system were carried out. The physical and chemical properties of the catalysts were analyzed by XRD, BET, XPS, SEM, O2-TPD, and H2-TPR. The effects of loading and Ce doping on catalyst activity were studied. The results show that the Mn2O3 catalyst exhibited the best activity at 300 ℃, and the NO conversion rate of Mn2O3 was 78.2%. The relative content of Oα adsorbed on the surface of the Mnx/Al catalyst decreased obviously by loading Mn2O3 on γ-Al2O3, which led to the decrease in catalyst activity. And the temperature window moved to the high-temperature region. After doping Ce, the dispersion of Mn enhanced, and the relative content of oxygen Oα adsorbed on the surface increased. The low-temperature activity and fluidity of oxygen in catalysts were improved. Among them, the Mn0.2Ce0.08/Al catalyst obtained a high specific surface area, good pore structure, large oxygen storage capacity, and excellent surface oxygen species. The corresponding NO conversion rate reached 83.5% at 290 ℃. Then, the effects of operating parameters such as space velocity, NO concentration, and O2 content on the catalytic activity of Mn0.2Ce0.08/Al were discussed. The experimental results show that the NO conversion rate of Mn0.2Ce0.08/Al decreased with increasing NO concentration and space velocity. The O2 content had a positive effect on the catalytic activity of the catalyst. However, the NO conversion rate tended to be stable due to the saturation of oxygen adsorbed on the catalyst. Through cycling experiments, we found that Mn2O3, Mn0.2/Al, and Mn0.2Ce0.08/Al catalysts showed good oxidation stabilities for NO oxidation. The evaluation of the water and sulfur resistance of the catalyst shows that the toxicity of SO2 was reduced by the aqueous atmosphere to a certain extent. Through the structural optimization of the basic model and the calculation of the NO-SCO reaction path, the results show that the NO-SCO reaction on the Mn2O3 (110) face followed the ER mechanism more. For the Mn2O3/Al2O3 (110) surface, the LH-MvK hybrid mechanism can greatly reduce the desorption energy barrier of the reaction intermediates, which is more favorable for the NO-SCO reaction. The catalytic mechanisms of the MnxCey/Al catalysts require further in-depth research.


Assuntos
Temperatura Baixa , Água , Temperatura , Oxirredução , Oxigênio , Catálise
16.
Front Endocrinol (Lausanne) ; 14: 1108125, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484943

RESUMO

Background: Central lymph node metastases (CLNM) in papillary thyroid microcarcinoma (PTMC) are common, but management through prophylactic central lymph node dissection (pCLND) remains controversial. In this study, the independent predictors of CLNM in PTMC were retrospectively studied based on ultrasound and pathological data, and we aim to establish the prediction model to predict CLNM in PTMC. Methods: This study included a total of 1,506 patients who underwent thyroid surgery for PTMC at the First Affiliated Hospital of Chongqing Medical University from 2015 to 2018. Ultrasound and clinicopathological features were summarized and analyzed. Univariate and multivariate analyses were performed to determine the risk factors associated with CLNM. The prediction model is established and verified according to the multivariate analysis results. The Kaplan-Meier curve was used to evaluate the effect of CLNM on survival. Results: The CLNM rate was 44.5% (670/1,506). Multivariate analysis showed that men, younger age, smaller diameter, ETE, microcalcification, without Hashimoto's thyroiditis, and multifocal were independent risk predictors of CLNM. Nomogram has a good discriminative ability (C-index: 0.755 in the validation group), and the calibration effect is good. In the DCA curve, the CLNM prediction model performed better net benefit given any high-risk thresholds. The median follow-up time was 30 months (12-59 months), 116 cases were lost, and the follow-up rate was 92.8% (1,506/1,622). Of the 1,506 patients included, 12 (0.8%) experienced recurrence. Conclusion: The likelihood of CLNM can be objectively quantified before surgery by using this reliable and accurate nomogram that combines preoperative ultrasound with clinicopathological features. Clinicians can use this nomogram to assess central lymph node status in patients with PTMC and consider prophylactic CND in patients with high scores.


Assuntos
Nomogramas , Neoplasias da Glândula Tireoide , Masculino , Humanos , Metástase Linfática , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia
17.
Nanoscale ; 15(35): 14338-14345, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37581287

RESUMO

Low-cost micro-sized silicon is an attractive replacement for commercial graphite anodes in advanced lithium-ion batteries (LIBs) but suffers from particle fracture during cycling. Hybridizing micro-sized silicon with conductive carbon materials, especially graphene, is a practical approach to overcome the volume change issue. However, micro-sized silicon/graphene anodes prepared via the conventional technique encounter sluggish Li+ transport due to the lack of efficient electrolyte diffusion channels. Here, we present a facile and scalable method to establish efficient Li+ transport channels through direct foaming from the laminated graphene oxide/micro-sized silicon membrane followed by annealing. The conductive graphene layers and the Li+ transport channels endow the composite material with excellent electronic and ionic conductivity. Moreover, the interconnected graphene layers provide a robust framework for micro-sized silicon particles, allowing them to transform decently in the graphene layer space. Consequently, the prepared hybrid material, namely foamed graphene/micro-sized Si (f-G-Si), can work as a binder-free and free-standing anode without additives and deliver remarkable electrochemical performance. Compared with the control samples, micro-sized silicon wrapped by laminated graphene layers (G-Si) and commercial micro-sized Si, f-G-Si maximizes the utilization of silicon and demonstrates superior performance, disclosing the role of Li+ diffusion channels. This study sheds light on the rational design and manufacture of silicon anodes and beyond.

18.
Adv Mater ; 35(21): e2212157, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36841944

RESUMO

Silicon is attractive for lithium-ion batteries and beyond but suffers large volume change upon cycling. Hierarchical tactics show promise yet lack control over the unit construction and arrangement, limiting stability improvement at the practical level. Here, a protocol is developed as controlled isotropic canalization of microsized silicon. Distinct from the existing strategies, it involves isotropic canalization by honeycomb-like radial arrangement of silicon nanosheets, and canal consolidation by controlled dual bonding of silicon with carbon. The proof-of-concept nitrogen-doped carbon dual-bonded silicon honeycomb-like microparticles, specifically with a medium density of CNSi and COSi bonds, exhibit stable cycling impressively at high rates and industrial-scale loadings. Two key issues involve isotropic canalization facilitating ion transport in all directions of individual granules and controlled consolidation conferring selective ion permeation and securing charge transport. The study highlights the configurational isotropy and interfacial bonding density, and provides insight into rational design and manufacture of silicon and others with industry-viable features.

19.
Nanoscale ; 15(32): 13272-13279, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37526608

RESUMO

Metal fluoride conversion cathodes are promising for the production of cheap, sustainable, and high-energy lithium-ion batteries. Yet, such systems are plagued by active material dissolution that causes capacity fade and hinders commercialization. Here, a covalent netting strategy is proposed to overcome this hurdle. In a proof-of-concept design, polydopamine derived carbon-mediated covalent binding inhibited the dissolution, while the pyrolyzed bacterial cellulose netting structure furnished fast electronic and ionic transport pathways. We demonstrate high-capacity, high-rate and long-lasting stability attained at practical loading levels. Our investigations suggest that the covalent netting-enabled formation of a robust and efficient blocking layer, highly competent in suppressing the leaching, is key for a stable performance. The successful stabilization of metal difluorides in the absence of electrolyte engineering opens an avenue for their practical deployment in future higher-level but lower-cost batteries, and provides a solution to similar challenges encountered by other dissolving energy electrode materials.

20.
Front Immunol ; 14: 1165510, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063918

RESUMO

Background: Immune function, nutrition status, and inflammation influence tumor initiation and progression. This was a retrospective multicenter cohort study that investigated the prognostic value and clinical relevance of immune-, inflammatory-, and nutritional-related biomarkers to develop a novel prognostic immune-inflammatory-nutritional score (PIIN score) for patients with intrahepatic cholangiocarcinoma (ICC). Methods: The clinical data of 571 patients (406 in the training set and 165 in the validation set) were collected from four large hepato-pancreatico-biliary centers of patients with ICC who underwent surgical resection between January 2011 and September 2017. Twelve blood biomarkers were collected to develop the PIIN score using the LASSO Cox regression model. The predictive value was further assessed using validation datasets. Afterward, nomograms combining the PIIN score and other clinicopathological parameters were developed and validated based on the calibration curve, time-dependent AUC curves, and decision curve analysis (DCA). The primary outcomes evaluated were overall survival (OS) and recurrence-free survival (RFS) from the day of primary resection of ICC. Results: Based on the albumin-bilirubin (ALBI) grade, neutrophil- to- lymphocyte ratio (NLR), prognostic nutritional index (PNI), and systemic immune- inflammation index (SII) biomarkers, the PIIN score that classified patients into high-risk and low-risk groups could be calculated. Patients with high-risk scores had shorter OS (training set, p < 0.001; validation set, p = 0.003) and RFS (training set, p < 0.001; validation set, p = 0.002) than patients with low-risk scores. The high PIIN score was also associated with larger tumors (≥5 cm), lymph node metastasis (N1 stage), multiple tumors, and high tumor grade or TNM (tumor (T), nodes (N), and metastases (M)) stage. Furthermore, the high PIIN score was a significant independent prognostic factor of OS and RFS in both the training (p < 0.001) and validation (p = 0.003) cohorts, respectively. A PIIN-nomogram for individualized prognostic prediction was constructed by integrating the PIIN score with the clinicopathological variables that yielded better predictive performance than the TNM stage. Conclusion: The PIIN score, a novel immune-inflammatory-nutritional-related prognostic biomarker, predicts the prognosis in patients with resected ICC and can be a reliable tool for ICC prognosis prediction after surgery. Our study findings provide novel insights into the role of cancer-related immune disorders, inflammation, and malnutrition.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Prognóstico , Estudos de Coortes , Biomarcadores , Inflamação , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/cirurgia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA