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1.
Int Immunopharmacol ; 143(Pt 1): 113229, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39357208

RESUMEN

T-bet and Eomes, both T-box transcription factors, have been extensively studied for their critical roles in the differentiation and functional maintenance of various immune cells. In this review, we provide a focused overview of their contributions to the transcriptional activation and differentiation, development, and terminal maturation of natural killer cells and innate lymphoid cell 1 cells. Furthermore, the interplay between T-bet and Eomes in regulating NK cell function, and its subsequent implications for immune responses against infections and tumors, is thoroughly examined. The review explores the ramifications of dysregulated transcription factor expression, examining its impact on homeostatic balance and its role in a spectrum of disease models. Expression variances among distinct NK cell subsets resident in different tissues are highlighted to underscore the complexity of their biological roles. Collectively, this work aims to expand the current understanding of NK cell biology, thereby paving the way for innovative approaches in the realm of NK cell-based immunotherapies.

2.
ACS Omega ; 9(40): 42010-42026, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39398160

RESUMEN

The present study focuses on a middle-arch dual-channel municipal solid waste (MSW) incinerator facing issues of high NO x emission and overheating. To address these problems and optimize the incinerator, an advanced numerical simulation method was employed to comprehensively assess its bed combustion, freeboard combustion, and NO x emission characteristics. A multiphase fuel bed model considering large-particle characteristics of MSW was developed, coupled with a three-dimensional (3D) model for combustion in freeboard. The analysis revealed that the observed issues stem from multiple factors, including primary-to-secondary air ratio, flame propagation in bed, release of volatiles from bed, and distribution and mixing of components in freeboard. Reducing the proportion of primary air and correspondingly increasing secondary air effectively alleviated the localized overheating in the furnace and reduced NO x emission. Further adjustments to the distribution of primary air in three stages delaying air supply toward the burnout stage, together with the decrease in the grate movement speed, can better control the amount and speciation of N released from the bed. Implementing a counterflow mixing strategy with NH3 in the front channel and NO in the rear channel can greatly reduce the original NO x emission concentration to 95.94 mg/(N·m3), as predicted by a numerical simulation. Subsequent practical adjustments to an actual incinerator led to notable improvements, clearly optimizing the localized high-temperature issues at various locations, especially the front channel suffering severe slagging problems, with the temperature reduced from 1118 to 957 °C. Meanwhile, NO x emission concentration decreased from 200 mg/(N·m3) to around 50 mg/(N·m3), with no negative effect on the boiler load.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39217591

RESUMEN

The composition and characteristics of emergency patients in the Affiliated Brain Hospital, Guangzhou Medical University during 2020-2022 were retrospectively analyzed to provide data support for the optimization of the process of psychiatric emergency and the elastic allocation of emergency medical staff. This study collected data from patients who sought medical attention at the emergency department of the Affiliated Brain Hospital, Guangzhou Medical University between January 1, 2020, and December 31, 2022. The fundamental information of these patients was statistically analyzed using descriptive analytic methods. In addition, a comprehensive statistical analysis was performed on the data of patient visits, which included precise triage time points, months, and seasons, in order to evaluate the temporal distribution of patient visits. The patient population had an average age of 36.4 years and was slightly more female (54.08%). The mean age of the male and female patients was 36.4 ± 18.91 and 36.4 ± 16.80 years, respectively. There was no statistically significant age difference between the male and female patients (p > 0.05). The top five diseases were mental disorder (6,483 cases), bipolar disorder (3,017 cases), depressive episode (2522 cases), schizophrenia (1778 cases) and anxiety state (1097 cases), accounting for 35.63%, 16.58%, 13.86%, 9.77% and 6.03% of the total, respectively. Additionally, a notable record of psychiatric drug intoxication was noted. Significant comorbidity with physical disorders, such as hypertension (9.36%), hypokalemia (3.41%), diabetes (2.83%), and cerebral infarction (2.79%), was also seen. The results of seasonal and monthly analysis indicated that emergency attendance patterns fluctuated, peaking in the spring and fall. The patterns of daily visits also revealed two peak times. The first peak occurs from 8:00 to 10:00, and the second peak occurs from 14:00 to 16:00. This study emphasizes the increasing occurrence of mental problems in psychiatric crises, particularly among younger populations, underscoring the necessity for comprehensive care methods. Specialized treatment methods and collaborative networks are required to address the substantial prevalence of psychiatric medication poisoning. Efficient allocation of resources and heightened security protocols are vital in emergency departments, particularly during periods of high demand and in handling instances of patient hostility.

5.
Biomed Opt Express ; 15(9): 5328-5348, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39296393

RESUMEN

Many diseases, such as inflammation, dropsy, or tumors, often cause alterations in the mechanical stiffness of human tissues. Ultrasound-based techniques are commonly adopted in clinics for stiffness assessment, whereas optical methodologies hold promise for sensing strain changes and providing optical information pertaining to the microcirculatory network, thereby facilitating comprehensive measurements of tissue physiopathology. Diffuse correlation spectroscopy (DCS), an emerging dynamic light scattering technique, has been used to capture the enhanced motion of light scatterers induced by acoustic radiation force (ARF). Theoretically, the amplitude of this enhanced scatterers motion is related to the medium stiffness. Based on this relationship, we report a light coherent technique that combines ARF and DCS to qualitatively evaluate changes in the stiffness of medium. We experimentally demonstrate the accuracy and feasibility of this technique for probing stiffness in homogeneous phantom by comparing it with independent ultrasound methods. Additionally, we explore a potential application of this technique in distinguishing between fluid filled lesion and homogeneous tissue through heterogeneous phantom experiments. This unique combination of ARF and DCS, namely, acoustomotive DCS (AM-DCS), would provide an alternative way to measure particle-motion related stiffness, thereby assisting in the diagnosis and treatment of diseases.

6.
J Phys Chem B ; 128(34): 8170-8182, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39162304

RESUMEN

The performance of lithium metal batteries can be significantly enhanced by incorporating fluorinated ether-based electrolytes, yet the solid electrolyte interphase (SEI) formation mechanism on lithium metal surfaces remains elusive. This study employs classical and ab initio molecular dynamics simulations to investigate the decomposition mechanisms of lithium bis(fluoromethanesulfonyl)imide (LiFSI) in 1,2-diethoxyethane (DEE) and its fluorinated analogues, F5DEE and F2DEE, when in contact with lithium metal. Our findings indicate that F5DEE-based electrolytes favor the formation of a FSI-rich primary solvation shell around Li+, while F2DEE-based electrolytes yield a solvent-rich environment. The normalized number density at the Li/electrolyte/Li interface shows a depletion of FSI anions in the electrochemical double layer (EDL) structure near the Li anode upon charging, with the distance between the first main peak of the FSI anion and Li anode following the order F5DEE < DEE < F2DEE. Analysis of the electronic projected density of states and charge transfer dynamics unveils the reductive dissociation pathways of FSI anions and fluorinated DEE solvents on the lithium metal surface, taking into account the influence of the EDL structure. DEE is identified as the most reduction-stable solvent, leading to the selective dissociation of FSI anions and the formation of an entirely inorganic SEI. In contrast, F2DEE displays a pronounced reduction tendency, forming an organic-rich SEI due to the solvent-dominated lowest unoccupied molecular orbital at the interface. F5DEE, competing with FSI anions for reduction, results in the formation of an inorganic-rich hybrid SEI with the highest LiF content. The simulation results correlate well with experimental observations and underscore the pivotal role of various fluorinated functional groups in the formation of EDL and SEI near the lithium metal surface.

7.
Cancer Lett ; 601: 217149, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39117066

RESUMEN

Understanding the determinants of long-term liver metastasis (LM) outcomes in gastrointestinal stromal tumor (GIST) patients is crucial. We established the feature selection model of intratumoral microbiome at the surgery, achieving robust predictive accuracies of 0.953 and 0.897 AUCs in discovery (n = 74) and validation (n = 34) cohorts, respectively. Notably, despite the significant reduction in LM occurrence with adjuvant imatinib (AI) treatment, intratumoral microbiome exerted independently stronger effects on post-operative LM. Employing both 16S and full-length rRNA sequencing, we pinpoint intracellular Shewanella algae as a foremost LM risk factor in both AI- and non-AI-treated patients. Experimental validation confirmed S. algae's intratumoral presence in GIST, along with migration/invasion-promoting effects on GIST cells. Furthermore, S. algae promoted LM and impeded AI treatment in metastatic mouse models. Our findings advocate for incorporating intratumoral microbiome evaluation at surgery, and propose S. algae as a therapeutic target for LM suppression in GIST.


Asunto(s)
Neoplasias Gastrointestinales , Tumores del Estroma Gastrointestinal , Mesilato de Imatinib , Neoplasias Hepáticas , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/microbiología , Mesilato de Imatinib/farmacología , Mesilato de Imatinib/uso terapéutico , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/microbiología , Animales , Ratones , Femenino , Masculino , Neoplasias Gastrointestinales/patología , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/microbiología , Quimioterapia Adyuvante/métodos , Persona de Mediana Edad , Microbiota/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Anciano
8.
Nat Commun ; 15(1): 6255, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048547

RESUMEN

Evolution of SARS-CoV-2 variants emphasizes the need for multivalent vaccines capable of simultaneously targeting multiple strains. SCTV01E is a tetravalent COVID-19 vaccine derived from the spike protein of SARS-CoV-2 variants Alpha, Beta, Delta, and Omicron BA.1. In this double-blinded placebo-controlled pivotal efficacy trial (NCT05308576), the primary endpoint was vaccine efficacy (VE) against COVID-19 seven days post-vaccination in individuals without recent infection. Other endpoints included evaluating safety, immunogenicity, and the VE against all SARS-CoV-2 infections in individuals meeting the study criteria. Between December 26, 2022, and January 15, 2023, 9,223 individuals were randomized at a 1:1 ratio to receive SCTV01E or a placebo. SCTV01E showed a VE of 69.4% (95% CI: 50.6, 81.0) 7 days post-vaccination, with 75 cases in the placebo group and 23 in the SCTV01E group for the primary endpoint. VEs were 79.7% (95% CI: 51.0, 91.6) and 82.4% (95% CI: 57.9, 92.6), respectively, for preventing symptomatic infection and all SARS-CoV-2 infections 14 days post-vaccination. SCTV01E elicited a 25.0-fold higher neutralizing antibody response against Omicron BA.5 28 days post-vaccination compared to placebo. Reactogenicity was generally mild and transient, with no reported vaccine-related SAE, adverse events of special interest (AESI), or deaths. The trial aligned with the shift from dominant variants BA.5 and BF.7 to XBB, suggesting SCTV01E as a potential vaccine alternative effective against present and future variants.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Eficacia de las Vacunas , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Método Doble Ciego , Femenino , Masculino , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , SARS-CoV-2/inmunología , Adulto , Persona de Mediana Edad , Anticuerpos Antivirales/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/inmunología , Anciano , Adulto Joven , Inmunogenicidad Vacunal , Adolescente , Vacunación/métodos
9.
Cancer Immunol Immunother ; 73(8): 151, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832951

RESUMEN

BACKGROUND: Immunotherapy for gastric cancer remains a challenge due to its limited efficacy. Metabolic reprogramming toward glycolysis has emerged as a promising avenue for enhancing the sensitivity of tumors to immunotherapy. Pyruvate dehydrogenase kinases (PDKs) play pivotal roles in regulating glycolysis. The importance of PDKs in the context of gastric cancer immunotherapy and their potential as therapeutic targets have not been fully explored. METHODS: PDK and PD-L1 expression was analyzed using data from the GSE66229 and The Cancer Genome Atlas (TCGA) cohorts. Additionally, the Immune Checkpoint Blockade Therapy Atlas (ICBatlas) database was utilized to assess PDK expression in an immune checkpoint blockade (ICB) therapy group. Subsequently, the upregulation of PD-L1 and the enhancement of anticancer effects achieved by targeting PDK were validated through in vivo and in vitro assays. The impact of PDK on histone acetylation was investigated using ChIP‒qPCR to detect changes in histone acetylation levels. RESULTS: Our analysis revealed a notable negative correlation between PD-L1 and PDK expression. Downregulation of PDK led to a significant increase in PD-L1 expression. PDK inhibition increased histone acetylation levels by promoting acetyl-CoA generation. The augmentation of acetyl-CoA production and concurrent inhibition of histone deacetylation were found to upregulate PD-L1 expression in gastric cancer cells. Additionally, we observed a significant increase in the anticancer effect of PD-L1 antibodies following treatment with a PDK inhibitor. CONCLUSIONS: Downregulation of PDK in gastric cancer cells leads to an increase in PD-L1 expression levels, thus potentially improving the efficacy of PD-L1 immune checkpoint blockade therapy.


Asunto(s)
Antígeno B7-H1 , Glucólisis , Inmunoterapia , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Neoplasias Gástricas , Regulación hacia Arriba , Antígeno B7-H1/metabolismo , Humanos , Animales , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Inmunoterapia/métodos , Ratones , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Desnudos
11.
Cancer Lett ; 593: 216935, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38704136

RESUMEN

Hepatocellular carcinoma (HCC) is a prevalent malignancy characterized by complex heterogeneity and drug resistance. Resistance to ferroptosis is closely related to the progression of HCC. While HCC tumors vary in their sensitivity to ferroptosis, the precise factors underlying this heterogeneity remain unclear. In this study, we sought to elucidate the mechanisms that contribute to ferroptosis resistance in HCC. Whole-genome CRISPR/Cas9 screen using a subtoxic concentration (IC20) of ferroptosis inducer erastin in the HCC cell line Huh7 revealed TRIM34 as a critical driver of ferroptosis resistance in HCC. Further investigation revealed that TRIM34 suppresses ferroptosis in HCC cells, promoting their proliferation, migration, and invasion both in vitro and in vivo. Furthermore, TRIM34 expression is elevated in HCC tumor tissues, correlating with a poor prognosis. Mechanistically, TRIM34 directly interacts with Up-frameshift 1 (UPF1), a core component of the nonsense-mediated mRNA decay (NMD) pathway, to promote its ubiquitination and degradation. This interaction suppresses GPX4 transcript degradation, thus promoting the protein levels of this critical ferroptosis suppressor in HCC. In light of the close crosstalk between ferroptosis and the adaptive immune response in cancer, HCC cells with targeting knockdown of TRIM34 exhibited an improved response to anti-PD-1 treatment. Taken together, the TRIM34/UPF1/GPX4 axis mediates ferroptosis resistance in HCC, thereby promoting malignant phenotypes. Targeting TRIM34 may thus represent a promising new strategy for HCC treatment.


Asunto(s)
Sistemas CRISPR-Cas , Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Animales , Humanos , Ratones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Inmunoterapia/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Portadoras/antagonistas & inhibidores
12.
iScience ; 27(6): 109821, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38770131

RESUMEN

The cyclic AMP-responsive element-binding protein (CREB)-regulated transcription coactivator 2 (CRTC2) is a crucial regulator of hepatic lipid metabolism and gluconeogenesis and correlates with tumorigenesis. However, the mechanism through which CRTC2 regulates hepatocellular carcinoma (HCC) progression is largely unknown. Here, we found that increased CRTC2 expression predicted advanced tumor grade and stage, as well as worse prognosis in patients with HCC. DNA promoter hypomethylation led to higher CRTC2 expression in HCC. Functionally, CRTC2 contributed to HCC malignant phenotypes through the activated Wnt/ß-catenin pathway, which could be abrogated by the small-molecular inhibitor XAV-939. Moreover, Crtc2 facilitated tumor growth while concurrently downregulating the PD-L1/PD-1 axis, resulting in primary resistance to immunotherapy. In immunocompetent mice models of HCC, targeting Crtc2 in combination with anti-PD-1 therapy prominently suppressed tumor growth by synergistically enhancing responsiveness to immunotherapy. Collectively, targeting CRTC2 might be a promising therapeutic strategy to sensitize immunotherapy in HCC.

13.
Front Microbiol ; 15: 1384459, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774504

RESUMEN

Pine wilt disease caused by Bursaphelenchus xylophilus poses a serious threat to the economic and ecological value of forestry. Nematode trapping fungi trap and kill nematodes using specialized trapping devices, which are highly efficient and non-toxic to the environment, and are very promising for use as biological control agents. In this study, we isolated several nematode-trapping fungi from various regions and screened three for their high nematocidal efficiency. However, the effectiveness of these fungi as nematicides is notably influenced by temperature and exhibits different morphologies in response to temperature fluctuations, which are categorized as "NA," "thin," "dense," and "sparse." The trend of trap formation with temperature was consistent with the trend of nematocidal efficiency with temperature. Both of which initially increased and then decreased with increasing temperature. Among them, Arthrobotrys cladodes exhibited the highest level of nematocidal activity and trap formation among the tested species. Transcriptome data were collected from A. cladodes with various trap morphologies. Hydrolase activity was significantly enriched according to GO and KEGG enrichment analyses. Eight genes related to hydrolases were found to be consistent with the trend of trap morphology with temperature. Weighted gene co-expression analysis and the Cytoscape network revealed that these 8 genes are associated with either mitosis or autophagy. This suggests that they contribute to the formation of "dense" structures in nematode-trapping fungi. One of these genes is the serine protein hydrolase gene involved in autophagy. This study reveals a potentially critical role for hydrolases in trap formation and nematocidal efficiency. And presents a model where temperature affects trap formation and nematocidal efficiency by influencing the serine protease prb1 involved in the autophagy process.

14.
Angew Chem Int Ed Engl ; 63(24): e202405763, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38607321

RESUMEN

Photocatalytic oxygen reduction reactions and water oxidation reactions are extremely promising green approaches for massive H2O2 production. Nonetheless, constructing effective photocatalysts for H2O2 generation is critical and still challenging. Since the network topology has significant impacts on the electronic properties of two dimensional (2D) polymers, herein, for the first time, we regulated the H2O2 photosynthetic activity of 2D covalent organic frameworks (COFs) by topology. Through designing the linking sites of the monomers, we synthesized a pair of novel COFs with similar chemical components on the backbones but distinct topologies. Without sacrificial agents, TBD-COF with cpt topology exhibited superior H2O2 photoproduction performance (6085 and 5448 µmol g-1 h-1 in O2 and air) than TBC-COF with hcb topology through the O2-O2⋅--H2O2, O2-O2⋅--O2 1-H2O2, and H2O-H2O2 three paths. Further experimental and theoretical investigations confirmed that during the H2O2 photosynthetic process, the charge carrier separation efficiency, O2⋅- generation and conversion, and the energy barrier of the rate determination steps in the three channels, related to the formation of *OOH, *O2 1, and *OH, can be well tuned by the topology of COFs. The current study enlightens the fabrication of high-performance photocatalysts for H2O2 production by topological structure modulation.

15.
Front Cardiovasc Med ; 11: 1286620, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38576421

RESUMEN

Background: Chemotherapy with anthracyclines can cause cardiotoxicity, possibly leading to stopping treatment in some cancer patients. In cardio-oncology research, preventing and minimizing anthracycline-induced cardiotoxicity (AIC) is a hot issue. For the treatment of AIC, calycosin (CA), an isoflavone component in astragali radix (AR), has become a research focus. However, the elaborate mechanisms of calycosin treating AIC remain to be unrevealed. Aim of the study: To explore the effects of CA on AIC through multiple dimensions concerning network pharmacology, molecular docking, and experimental evaluations. Methods: The study evaluated calycosin's potential targets and mechanisms for treating AIC using network pharmacology and molecular docking. The candidate genes/targets of CA and AIC were screened using the online-available database. Protein-protein interactions (PPI) between the common targets were constructed using the STRING platform, and the results were then visualized using Cytoscape. Molecular docking was used to evaluate the strength of the binding force between CA and the common targets. The possible pharmacological mechanisms of CA were explained by pathway enrichment and GSEA. Subsequently, the candidate targets were identified in vitro experiments. Results: Network pharmacology effectively discovered the CA's multitarget intervention in AIC, including TNF, ABCC1, TOP2A, ABCB1, and XDH. CA binds to the ATP-binding cassette subfamily B member 1(ABCB1) had the highest binding energy (-7.5 kcal/mol) according to the molecular docking analysis and was selected and visualized for subsequent analysis. In vitro experiments showed that ABCB1 exhibited significant time-curve changes under different doses of doxorubicin (DOX) compared with DMSO control experiments. The anti-AIC pharmacological mechanism of CA were revealed by highlighting the biological processes of oxidative stress (OR) and inflammation. Conclusions: We employed a practicable bioinformatics method to connect network and molecular docking to determine the calycosin's therapeutic mechanism against AIC and identified some bioinformatics results in in vitro experiments. The results presented show that CA may represent an encouraging treatment for AIC.

17.
Langmuir ; 40(15): 8133-8143, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38568837

RESUMEN

Aluminum (Al) alloy surfaces are prone to serious corrosion in humid and salt-laden environments, which promotes the development of numerous protective approaches. Although the amorphous state is more conducive to improve corrosion resistance compared with the crystalline state, it still faces coating design problems like insufficient adhesive strength and flaking-off tendency. Here, we propose a strategy of femtosecond laser-assisted oxygen-rich doping to in situ create a dense high-quality passivation layer on Al alloy surfaces. With respect to the femtosecond laser processing in traditional air ambience, the material surface modifications within the oxygen-rich environment demonstrate some distinctiveness. For the ridge area of the laser ablation grooves, the oxidation surface is separated into two layers: the outer region presents a loose and porous appearance similar to the observations in the air ambience, while the inner region exhibits complete and homogeneous oxidation, especially associated with the continuous distribution of the amorphous substance, in sharp contrast to the nanoscale discrete amorphous formation in the air case. Simultaneously, the high degree of material oxidization with the amorphous phase is also developed on the wallside area of the groove valleys, which is much different from the incomplete oxidation in the air ambience. As a result, the measured corrosion current decreases by 49 times to a value of Icorr = 1.19 × 10-10 A/cm2 relative to the laser treatment in the air environment. Such a method offers the prospect for elevating the anticorrosion performance of metal surfaces.

18.
Materials (Basel) ; 17(3)2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38591486

RESUMEN

Owing to the challenge of capturing the dynamic behaviour of metal experimentally, high-precision numerical simulations have become essential for analysing dynamic characteristics. In this study, calculation accuracy was improved by analysing the impact of constitutive models using the finite element (FE) model, and the deep learning (DL) model was employed for result analysis. The results showed that FE simulations with these models effectively capture the elastic-plastic response, and the ZA model exhibits the highest accuracy, with a 26.0% accuracy improvement compared with other models at 502 m/s for Hugoniot elastic limit (HEL) stress. The different constitutive models offer diverse descriptions of stress during the elastic-plastic response because of temperature effects. Concurrently, the parameters related to the yield strength at quasi-static influence the propagation speed of elastic waves. Calculation show that the yield strength at quasi-static of 6061 Al adheres to y = ax + b for HEL stress. The R-squared (R2) and mean absolute error (MAE) values of the DL model for HEL stress predictions are 0.998 and 0.0062, respectively. This research provides a reference for selecting constitutive models for simulation under the same conditions.

19.
Plants (Basel) ; 13(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38475521

RESUMEN

Forest biomass allocation is a direct manifestation of biological adaptation to environmental changes. Studying the distribution patterns of forest biomass along elevational gradients is ecologically significant for understanding the specific impacts of global change on plant resource allocation strategies. While aboveground biomass has been extensively studied, research on belowground biomass remains relatively limited. Furthermore, the patterns and driving factors of the belowground biomass proportion (BGBP) along elevational gradients are still unclear. In this study, we investigated the specific influences of climatic factors, soil nutrients, and key leaf traits on the elevational pattern of BGBP using data from 926 forests at 94 sites across China. In this study, BGBP data were calculated from the root biomass to the depth of 50 cm. Our findings indicate considerable variability in forest BGBP at a macro scale, showing a significant increasing trend along elevational gradients (p < 0.01). BGBP significantly decreases with increasing temperature and precipitation and increases with annual mean evapotranspiration (MAE) (p < 0.01). It decreases significantly with increasing soil phosphorus content and increases with soil pH (p < 0.01). Key leaf traits (leaf nitrogen (LN) and leaf phosphorus (LP)) are positively correlated with BGBP. Climatic factors (R2 = 0.46) have the strongest explanatory power for the variation in BGBP along elevations, while soil factors (R2 = 0.10) and key leaf traits (R2 = 0.08) also play significant roles. Elevation impacts BGBP directly and also indirectly through influencing such as climate conditions, soil nutrient availability, and key leaf traits, with direct effects being more pronounced than indirect effects. This study reveals the patterns and controlling factors of forests' BGBP along elevational gradients, providing vital ecological insights into the impact of global change on plant resource allocation strategies and offering scientific guidance for ecosystem management and conservation.

20.
Angew Chem Int Ed Engl ; 63(17): e202400045, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385624

RESUMEN

Zinc ion batteries (ZIBs) exhibit significant promise in the next generation of grid-scale energy storage systems owing to their safety, relatively high volumetric energy density, and low production cost. Despite substantial advancements in ZIBs, a comprehensive evaluation of critical parameters impacting their practical energy density (Epractical) and calendar life is lacking. Hence, we suggest using formulation-based study as a scientific tool to accurately calculate the cell-level energy density and predict the cycling life of ZIBs. By combining all key battery parameters, such as the capacity ratio of negative to positive electrode (N/P), into one formula, we assess their impact on Epractical. When all parameters are optimized, we urge to achieve the theoretical capacity for a high Epractical. Furthermore, we propose a formulation that correlates the N/P and Coulombic efficiency of ZIBs for predicting their calendar life. Finally, we offer a comprehensive overview of current advancements in ZIBs, covering cathode and anode, along with practical evaluations. This Minireview outlines specific goals, suggests future research directions, and sketches prospects for designing efficient and high-performing ZIBs. It aims at bridging the gap from academia to industry for grid-scale energy storage.

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