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1.
Plant Physiol ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39361658

RESUMEN

Mitogen-activated protein kinases (MAPKs/MPKs) are pivotal regulators in many stress-signaling pathways in plants. The dual phosphorylation of the TXY motif by MAP Kinase Kinases (MKKs) is essential for activating MAPKs. Here, we reveal a mechanism for MAPK activation that bypasses the need for MKKs. We identified rice (Oryza sativa) calcium-dependent protein kinase 5 (OsCPK5) and OsCPK13as positive regulators in salt stress tolerance. These kinases are essential for the full activation of OsMPK3 and OsMPK6 in response to elevated sodium levels, with both OsMPK3 and OsMPK6 also acting as positive regulators in rice salt tolerance. Biochemical analysis demonstrated that OsCPK5/13 directly interact with and activate OsMPK3/6 by phosphorylating the TXY motif in vitro and in vivo. Additionally, we have discovered that OsCPK5/13 relocate from the cell membrane to the nucleus in response to salt stress. This process relies on their N-terminal myristoylation and a calcium-dependent phosphorylation event within the N-terminus. Our results elucidate a MAPK activation pathway in rice that is independent of traditional MKK-mediated phosphorylation, highlighting the crucial roles of OsCPK5 and OsCPK13 in directly phosphorylating and activating OsMPK3/6, which are important for rice tolerance to salt stress.

2.
Cell ; 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39353437

RESUMEN

Complex structural variations (cxSVs) are often overlooked in genome analyses due to detection challenges. We developed ARC-SV, a probabilistic and machine-learning-based method that enables accurate detection and reconstruction of cxSVs from standard datasets. By applying ARC-SV across 4,262 genomes representing all continental populations, we identified cxSVs as a significant source of natural human genetic variation. Rare cxSVs have a propensity to occur in neural genes and loci that underwent rapid human-specific evolution, including those regulating corticogenesis. By performing single-nucleus multiomics in postmortem brains, we discovered cxSVs associated with differential gene expression and chromatin accessibility across various brain regions and cell types. Additionally, cxSVs detected in brains of psychiatric cases are enriched for linkage with psychiatric GWAS risk alleles detected in the same brains. Furthermore, our analysis revealed significantly decreased brain-region- and cell-type-specific expression of cxSV genes, specifically for psychiatric cases, implicating cxSVs in the molecular etiology of major neuropsychiatric disorders.

3.
J Nanobiotechnology ; 22(1): 541, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39238002

RESUMEN

Liver fibrosis is a serious global health issue for which effective treatment remains elusive. Chemical-induced hepatocyte-like cells (ciHeps) have emerged as an appealing source for cell transplantation therapy, although they present several challenges such as the risk of lung thromboembolism or hemorrhage. Apoptotic vesicles (apoVs), small membrane vesicles generated during the apoptosis process, have gained attention for their role in regulating various physiological and pathological processes. In this study, we generated ciHep-derived apoVs (ciHep-apoVs) and investigated their therapeutic potential in alleviating liver fibrosis. Our findings revealed that ciHep-apoVs induced the transformation of macrophages into an anti-inflammatory phenotype, effectively suppressed the activity of activated hepatic stellate cells (aHSCs), and enhanced the survival of hepatocytes. When intravenously administered to mice with liver fibrosis, ciHep-apoVs were primarily engulfed by macrophages and myofibroblasts, leading to a reduction in liver inflammation and fibrosis. Proteomic and miRNA analyses showed that ciHep-apoVs were enriched in various functional molecules that modulate crucial cellular processes, including metabolism, signaling transduction, and ECM-receptor interactions. ciHep-apoVs effectively suppressed aHSCs activity through the synergistic inhibition of glycolysis, the PI3K/AKT/mTOR pathway, and epithelial-to-mesenchymal transition (EMT) cascades. These findings highlight the potential of ciHep-apoVs as multifunctional nanotherapeutics for liver fibrosis and provide insights into the treatment of other liver diseases and fibrosis in other organs.


Asunto(s)
Apoptosis , Hepatocitos , Cirrosis Hepática , Animales , Ratones , Cirrosis Hepática/patología , Hepatocitos/metabolismo , Fibroblastos/metabolismo , Macrófagos/metabolismo , Células Estrelladas Hepáticas/metabolismo , Transducción de Señal , Masculino , Ratones Endogámicos C57BL , MicroARNs/metabolismo , MicroARNs/genética , Células RAW 264.7 , Humanos
4.
J Integr Plant Biol ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254487

RESUMEN

The utilization of metabolomics approaches to explore the metabolic mechanisms underlying plant fitness and adaptation to dynamic environments is growing, highlighting the need for an efficient and user-friendly toolkit tailored for analyzing the extensive datasets generated by metabolomics studies. Current protocols for metabolome data analysis often struggle with handling large-scale datasets or require programming skills. To address this, we present MetMiner (https://github.com/ShawnWx2019/MetMiner), a user-friendly, full-functionality pipeline specifically designed for plant metabolomics data analysis. Built on R shiny, MetMiner can be deployed on servers to utilize additional computational resources for processing large-scale datasets. MetMiner ensures transparency, traceability, and reproducibility throughout the analytical process. Its intuitive interface provides robust data interaction and graphical capabilities, enabling users without prior programming skills to engage deeply in data analysis. Additionally, we constructed and integrated a plant-specific mass spectrometry database into the MetMiner pipeline to optimize metabolite annotation. We have also developed MDAtoolkits, which include a complete set of tools for statistical analysis, metabolite classification, and enrichment analysis, to facilitate the mining of biological meaning from the datasets. Moreover, we propose an iterative weighted gene co-expression network analysis strategy for efficient biomarker metabolite screening in large-scale metabolomics data mining. In two case studies, we validated MetMiner's efficiency in data mining and robustness in metabolite annotation. Together, the MetMiner pipeline represents a promising solution for plant metabolomics analysis, providing a valuable tool for the scientific community to use with ease.

5.
Front Cell Dev Biol ; 12: 1421981, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296933

RESUMEN

Introduction: Breast cancer is a heterogeneous disease comprising various molecular subtypes, including Luminal A, Luminal B, human epidermal growth factor receptor-2 (HER2) positive, and triple negative types, each with distinct biological characteristics and behaviors. Triple negative breast cancer (TNBC) remains a particularly challenging subtype worldwide. Our study aims to evaluate whether Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) parameters, clinical pathological features, and biochemical indicators serve as prognostic risk factors for TNBC. Additionally, we explore correlations between biochemical indicators and 18F-FDG PET/CT parameters. Methods: We conducted a retrospective analysis of 95 TNBC patients who underwent preoperative 18F-FDG PET/CT examinations at Tianjin Medical University Cancer Institute and Hospital from 2013 to 2018. Collected data included 18F-FDG PET/CT parameters, clinical and pathological features, and biochemical indicators. We used Kaplan-Meier survival analysis and multivariate Cox regression analysis to evaluate associations between 18F-FDG PET/CT parameters/biochemical indicators and disease free survival (DFS)/overall survival (OS). The log-rank test determined significant differences in survival curves, and the Spearman correlation coefficient analyzed correlations between quantitative variables. Visualization and analysis were performed using R packages. Results: Among 95 TNBC patients, mean standardized uptake value (SUVmean) was significantly correlated with DFS. Fasting blood glucose (FBG), α- L-fucosylase (AFU) and Creatine kinase (CK) were independent predictors of DFS, while Precursor albumin (PALB) and CK were independent predictors of OS. FBG showed correlations with SUVpeak and SUVmean, and CK was correlated with peak standardized uptake value (SUVpeak). Our results indicated that 18F-FDG PET/CT parameters and biochemical indicators may constitute a new prognostic model for TNBC patients post-surgery. Discussion: We found that SUVmean, FBG, AFU and CK are predictive factors for DFS in TNBC patients post-surgery, while PALB and CK are predictive factors for OS, which prompts us to pay more attention to these indicators in clinical practice. Also 18F-FDG PET/CT parameters and biochemical indicators have potential utility in constituting a new prognostic model for TNBC patients post-surgery.

6.
Eco Environ Health ; 3(3): 271-280, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39252856

RESUMEN

Freshwater salinization is receiving increasing global attention due to its profound influence on nitrogen cycling in aquatic ecosystems and the accessibility of water resources. However, a comprehensive understanding of the changes in river salinization and the impacts of salinity on nitrogen cycling in arid and semi-arid regions of China is currently lacking. A meta-analysis was first conducted based on previous investigations and found an intensification in river salinization that altered hydrochemical characteristics. To further analyze the impact of salinity on nitrogen metabolism processes, we evaluated rivers with long-term salinity gradients based on in situ observations. The genes and enzymes that were inhibited generally by salinity, especially those involved in nitrogen fixation and nitrification, showed low abundances in three salinity levels. The abundance of genes and enzymes with denitrification and dissimilatory nitrate reduction to ammonium functions still maintained a high proportion, especially for denitrification genes/enzymes that were enriched under medium salinity. Denitrifying bacteria exhibited various relationships with salinity, while dissimilatory nitrate reduction to ammonium bacterium (such as Hydrogenophaga and Curvibacter carrying nirB) were more inhibited by salinity, indicating that diverse denitrifying bacteria could be used to regulate nitrogen concentration. Most genera exhibited symbiotic and mutual relationships, and the highest proportion of significant positive correlations of abundant genera was found under medium salinity. This study emphasizes the role of river salinity on environment characteristics and nitrogen transformation rules, and our results are useful for improving the availability of river water resources in arid and semi-arid regions.

7.
Water Res ; 267: 122472, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39305525

RESUMEN

This study examined the influence of water periods on river nitrogen cycling by analysing nitrogen functional genes and bacterial communities in the Qingshui River, an upstream tributary of the Yellow River in China. Nitrate nitrogen predominated as inorganic nitrogen during the low-flow seasons, whereas salinity was highest during the high-flow seasons. Overall, the functional gene abundance increased with decreasing water volume, and nitrogen concentrations were determined by various specific gene groups. The relative abundance of bacteria carrying these genes varied significantly across water periods. The abundance of Pseudomona, Hydrogenophaga (carrying narGHI and nirB genes), and Flavobacterium (carrying nirK, norBC, and nosZ genes) significantly increased during the low-flow seasons. Nitrogen transformation bacteria exhibited both symbiotic and mutualistic relationships. Microbial network nodes and sizes decreased with decreasing water volume, whereas modularity increased. Additionally, the water period affected the functional microbial community structure by influencing specific environmental factors. Among them, SO42- primarily determined the denitrification, dissimilatory nitrate reduction to ammonium, and assimilatory nitrate reduction to ammonium communities, whereas NO2--N and Mg2+ were the main driving factors for the nitrogen-fixing and nitrifying communities, respectively. These findings have substantial implications for better understanding the reduction in river nitrogen loads in arid and semi-arid regions during different water periods.

8.
Sci Rep ; 14(1): 22379, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333623

RESUMEN

The effects on the upper masonry structure and the construction parameters of shield cutting piles were studied during shield construction, focusing on a shield interval of Zhengzhou Metro Line 5. The study utilized the actual engineering case of left and right double-lane shields superimposed on cutting cement soil group pile composite foundations beneath masonry structures. Findings revealed that masonry structures within approximately 30 m (5.0 times the tunnel diameter) were impacted before and after shield cut pile construction, resulting in deflection and twisting deformations of houses along the central axes of the left and right tunnel lines. Implementation of "clay shock" grouting outside the shield shell, radial grouting through small conduits, shield tail synchronous grouting, and secondary reinforcement grouting effectively mitigated the disturbance caused by shield construction to the ground. When shield cut piles passed beneath masonry structures, pressure on the soil chamber, total thrust, and cutterhead speed were consistently controlled. Furthermore, the cutterhead torque was appropriately reduced, and slurry injection volume increased, contributing to better control of house settlement.

9.
Diabetes Metab Syndr Obes ; 17: 3447-3453, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39309307

RESUMEN

Purpose: Insulin resistance is associated with kidney impairment in patients with type 2 diabetes mellitus (T2DM). The triglyceride glucose-body mass index (TyG-BMI), which combines the TyG index with body mass index (BMI), has received significant attention as a tool for evaluating insulin resistance. Thus, the aim of this study was to explore the association between TyG-BMI and kidney impairment in patients with type 2 diabetes mellitus (T2DM). Patients and Methods: The cross-sectional analysis included 1080 patients with T2DM, and data were collected retrospectively. TyG-BMI was calculated by fasting blood glucose, triglyceride, and body mass index. Results: TyG-BMI was significantly higher in T2DM patients with albuminuria than those without albuminuria (232.16 [206.52-268.02] vs 229.83 [206.11-255.64], p =0.023). T2DM patients with chronic kidney disease (CKD) showed a significantly higher value of TyG-BMI compared with those without CKD (232.23 [206.46-268.28] vs 229.73 [206.11-255.49], p=0.014). Correlation analysis showed a significantly positive association between TyG-BMI and metabolic parameters including BMI (r = 0.866, p < 0.001), TG (r = 0.630, p < 0.001), TC (r = 0.119, p < 0.001), HDL-C (r = -0.374, p < 0.001), FBG (r = 0.297, p < 0.001), and HbA1c (r = 0.116, p < 0.001) in patients with T2DM. The binary logistic regression analysis found that TyG-BMI was an independent factor for albuminuria (OR = 1.004, 95% CI: 1.001-1.008, p = 0.010) and CKD (OR = 1.005, 95% CI: 1.001-1.008, p = 0.005) in patients with T2DM respectively. Conclusion: The study suggests that TyG-BMI is associated with kidney impairment in patients with T2DM. Given that TyG-BMI is a novel parameter of insulin resistance, the study results indicates that clinicians should pay close attention to screening for kidney impairment in T2DM patients with insulin resistance.

10.
Sensors (Basel) ; 24(16)2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39205007

RESUMEN

F-P (Fabry-Perot) pressure sensors have a wide range of potential applications in high-temperature, high-pressure, and high-dynamic environments. However, existing demodulation methods commonly rely on spectrometers, which limits their application to high-frequency pressure signal acquisition. To solve this problem, this study developed a self-compensated, three-wavelength demodulation system composite with an F-P pressure sensor and a thermocouple to construct a comprehensive sensing system. The system produces accurate pressure measurements in high-temperature, high-pressure, and high-dynamic environments. In static testing at room temperature, the sensing system shows excellent linearity, and the pressure sensitivity is 158.48 nm/MPa. In high-temperature testing, the sensing system maintains high linearity in the range of 100 °C to 700 °C, with a maximum pressure-indication error of about 0.13 MPa (0~5 MPa). In dynamic testing, the sensor exhibits good response characteristics at 1000 Hz and 5000 Hz sinusoidal pressure frequencies, with a signal-to-noise ratio (SNR) greater than 37 dB and 45 dB, respectively. These results indicate that the sensing system proposed in this study has significant competitive advantages in the field of high-temperature, high-speed, and high-precision pressure measurements and provides an important experimental basis and theoretical support for technological progress in related fields.

11.
Biodivers Data J ; 12: e125570, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39099603

RESUMEN

Background: Mycena (Pers.) Roussel (1806) is a large genus of Mycenaceae known for having small to medium-sized basidiomata. It is typified by the species Mycenagalericulata (Scop.) Gray. For years, many mycologists have made important contributions to understanding Mycena and several monographs have been published. Three specimens were collected from China that belonged to the genus Mycena. On the basis of morphological analysis and phylogenetic analyses employing DNA sequences, a new species is described. New information: Mycenabrunnescens sp. nov. is described as a new species from subtropical areas of China. It is characterised by its brown pileus, whitish lamellae that turns brown when bruised, orange to brown lamellae edges, the absence of pleurocystidia and cheilocystidia with simple or branched excrescences at the apex containing yellowish-brown contents. We performed phylogenetic analyses on a concatenated dataset comprising the internal transcribed spacer and large subunit regions of nuclear ribosomal RNA using Bayesian Inference and Maximum Likelihood methods. The result showed that the new taxon clustered in an independent group and is closely related to M.albiceps and M.flosoides.

12.
Thorac Cancer ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39098997

RESUMEN

BACKGROUND: Lung cancer is one of the major threats to human life worldwide. MiR-190 has been found to perform essential roles in multiple cancer progression; however, there have been no studies focused on its function and underlying regulatory mechanism in lung cancer. METHOD: The miR-190 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The cell functional experiments, including cell counting kit-8 (CCK-8), colony formation and transwell assay were conducted in vitro, as well as animal experiments performed in vivo. The regulation and potential binding sites of CBX4 on miR-190 were predicted by TCGA data set and JASPAR website and verified by ChIP assay and dual-luciferase reporter assay. The prospects binding site of miR-190-3p on CBX4 3'UTR region was predicted by StarBase and verified by dual-luciferase reporter assay. RESULTS: MiR-190 was decreased in lung cancer cells. The overexpression of miR-190 had no effects on cell proliferation, but significantly inhibited cancer metastasis both in vitro and in vivo. Moreover, miR-190 expression could be transcriptionally inhibited by CBX4, and CBX4 was the direct target of miR-190-3p. CONCLUSION: MiR-190 served as a cancer metastasis inhibitor in lung cancer and formed a regulatory loop with CBX4. These findings provided emerging insights into therapeutic targets and strategies for metastatic lung cancer.

13.
RSC Adv ; 14(35): 25852-25864, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39156749

RESUMEN

In this study, Cd1-x Na x Cu3Ti4O12 (x = 0, 0.02, 0.04, 0.06, and 0.08) ceramics were prepared via a solid-state method. The phase composition, microstructure, and defect characteristics as well as optical, dielectric, and nonlinear properties of the ceramics were systematically studied. A CuO second phase was detected in doped samples. Grain boundary precipitates, Na with a low melting point, and oxygen and cation vacancies together caused the grain size to first increase and then decrease with an increase in the Na+ doping amount. The abundant emerging cation vacancies with an increase in Na+ content led to a decrease in the optical energy band. The sample with x = 0.04 exhibited the highest ε' value (∼35 800) due to its largest grain size. Moreover, it possessed a lower tan δ (∼0.053) at 10 kHz, which was attributed to the multiplication of insulating grain boundaries. The huge dielectric constant originated from Maxwell-Wagner polarization at low frequencies and followed the internal barrier effect model. The lowest tan δ (∼0.037) and optimal nonlinear properties (α = 3.66 and E b = 3.82 kV cm-1) were obtained in the sample with x = 0.08, which were associated with its highest grain boundary resistance and barrier height. Electric modulus data proved that dielectric relaxation at low frequencies was associated with grain boundaries. Dielectric anomalies in the high temperature range were attributed to oxygen vacancies.

14.
RSC Adv ; 14(35): 25619-25628, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39148761

RESUMEN

This research focused on utilizing banana peel as the primary material for producing mesoporous biomass charcoal through one-step potassium hydroxide activation. Subsequently, the biomass charcoal underwent high-temperature calcination with varying impregnation ratios of KOH : BC for different durations in tubular furnaces set at different temperatures. The resultant biomass charcoal was then subjected to hydrothermal treatment with FeCl3·6H2O to produce biochar/iron oxide composites. The adsorption capabilities of these composites towards methylene blue (MB) were examined under various conditions, including pH (ranging from 3 to 12), temperature variations, and initial MB concentrations (ranging from 50 to 400 mg L-1). The adsorption behavior aligned with the Langmuir model and demonstrated quasi-secondary kinetics. After five adsorption cycles, the capacity decreased from 618.64 mg g-1 to 497.18 mg g-1, indicating considerable stability. Notably, Fe3O4-N-BC exhibited exceptional MB adsorption performance.

15.
Am J Health Promot ; : 8901171241275868, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162683

RESUMEN

PURPOSE: Healthcare professionals experience stressors that begin during training and persist into their careers that adversely impact their well-being. This study aims to identify students' and professionals' stress levels, satisfaction with wellness domains, barriers to wellness, and stress management practices. DESIGN: This study was a cross-sectional self-reported survey study. SETTINGS AND SAMPLE: The study included students (N = 242) and professionals (N = 237) from medicine, nursing, pharmacy, physical therapy, social work, and counseling/psychology. MEASURES: The Managing Health & Wellness in Health Professions Training and Practice survey was used to capture wellness practices and barriers among participants. Results: Students reported significantly higher perceived stress compared to professionals (P < 0.001). Total wellness is significantly higher among professionals compared to students (P < 0.001). A higher stress rate is significantly related to being female, having a lower wellness score, and facing more barriers (P < 0.001). Intellectual health is the most valuable wellness domain for providers (M = 3.71, SD = 0.9) and students (M = 3.43, SD = 0.85), followed by spiritual health for providers (M = 3.4, SD = 1.1), and work/learning environment for students (M = 3.33, SD = 0.93). Professionals and students are least satisfied with their physical and financial health. Barriers include fatigue, workload/productivity in clinical practice, work hours, and burnout. CONCLUSIONS: Healthcare professionals exhibit a variety of stress management practices, encounter barriers, and prioritize different wellness domains. Healthcare systems should incorporate self-care education into their curricula and implement systemic changes to foster a thriving healthcare workforce.

16.
Front Med ; 18(4): 744-751, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38958922

RESUMEN

Corona virus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has affected the whole world. Acquired thrombotic thrombocytopenic purpura (TTP) has been reported after administration of mRNA- or adenoviral vector-based COVID-19 vaccines, including Ad26.COV2-S, BNT162b2, mRNA-1273, and ChAdOx1 nCov-19. However, whether inactivated vaccines, such as CoronaVac, could cause TTP and whether the symptoms in TTPs caused by inactivated vaccines are different from previously reported cases are unknown. In this study, two cases were reported. Both cases developed TTP after the second CoronaVac vaccination shot, but not the first. They demonstrated symptoms of fever, neurological abnormalities, renal dysfunction, thrombocytopenia, and hemolysis. Both patients achieved complete remission through several sessions of plasma exchanges and immune suppression. The incidence of TTP in Nanjing area was analyzed. The number of patients with TTP was 12 in 2019, 6 in 2020, 16 in 2021, and 19 in 2022. To the authors' knowledge, this report is the first report of TTP associated with inactivated COVID-19 vaccine (CoronaVac). The rarity and delayed onset may be due to the relatively milder immune response caused by the inactivated vaccines than mRNA-based ones. Timely plasma exchange is a vital treatment for CoronaVac-related TTP, similar to activated vaccine-related TTP.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Púrpura Trombocitopénica Trombótica , Vacunas de Productos Inactivados , Humanos , Vacunas contra la COVID-19/efectos adversos , Púrpura Trombocitopénica Trombótica/terapia , Púrpura Trombocitopénica Trombótica/etiología , COVID-19/prevención & control , COVID-19/inmunología , Masculino , Femenino , Vacunas de Productos Inactivados/administración & dosificación , Persona de Mediana Edad , SARS-CoV-2/inmunología , Intercambio Plasmático , Adulto
17.
Inorg Chem ; 63(31): 14623-14629, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39038226

RESUMEN

Chalcopyrite copper-indium-gallium diselenides (CIGS) have emerged as promising materials with remarkable electronic properties and potential applicability to high-efficiency solar cells. The crystal and electronic structures of CIGS can be continuously tuned from their initial states under pressure. Although pressure-induced band gap closure in CIGS has been predicted in extensive theoretical studies, it has not been supported by experimental evidence. Here, we comprehensively investigate the pressure-dependent optical, electronic, and structural properties of Cu(In0.7Ga0.3)Se2 up to 42.6 GPa. Our experimental results reveal an irreversible electronic transition from the semiconducting to the metallic state at 14.3 GPa. Under compression, the Cu(In0.7Ga0.3)Se2 structure evolves from a tetragonal I4̅2d phase to an orthorhombic Pna21 phase, which has not been previously reported in chalcopyrite. More intriguingly, the Pna21 phase is irreversible and possesses smaller Cu-Se and In/Ga-Se bond lengths and a smaller Cu-Se-Cu bond angle than the I4̅2d phase. Density functional theory calculations indicate a lower enthalpy of the Pna21 phase than that of the I4̅2d phase at pressures above 10.6 GPa. Meanwhile, density of states calculations illustrate that metallization arises from the overlap of the Se p and Cu d orbitals as the bond length reduces. This pressure-induced behavior could facilitate the development of novel devices with various phenomena involving strong coupling of the mechanical, electrical, and optical properties of chalcopyrite.

19.
Chemistry ; 30(53): e202402023, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39032086

RESUMEN

This study presents the design, synthesis, and comprehensive characterization of a novel series of D-π-A type malononitrile-derived chromophores, BTC-1-BTC-4. Combining various spectroscopic techniques, nonlinear Z-scan measurements, and quantum chemical calculations, we revealed the intricate relationship between nonlinear optical properties and the interplay of molecular structure, intramolecular charge transfer (ICT), and dipole moments (µ). Our experimental and computational findings corroborate that the polarization degree in the ground state, the charge separation in the excited state and twisted intramolecular charge transfer (TICT) collectively dictate the nonlinear optical properties of the compounds. Notably, BTC-1 exhibits an exceptional nonlinear absorption coefficient ß value (2×10-8 m W-1), attributed to its optimized charge transfer efficiency and pronounced degree of charge separation. Our findings provide actionable insights for the rational design of high-performance organic Nonlinear optics (NLO) materials with potential applications in advanced photonic devices.

20.
ACS Nano ; 18(26): 16842-16852, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38912721

RESUMEN

The accelerated formation of lithium dendrites has considerably impeded the advancement and practical deployment of all-solid-state lithium metal batteries (ASSLMBs). In this study, a soft carbon (SC)-Li3N interface layer was developed with both ionic and electronic conductivity, for which the in situ lithiation reaction not only lithiated SC into LiC6 with good electronic/ionic conductivity but also successfully transformed the mixed-phase Li3N into pure-phase ß-Li3N with a high ionic conductivity/ion diffusion coefficient and stability to lithium metal. The mixed conductive interface layer facilitates fast Li+ transport at the interface and induces the homogeneous deposition of lithium metal inside it. This effectively inhibits the formation of lithium dendrites and greatly improves the performance of the ASSLMB. The ASSLMB assembled with the SC-Li3N interface layer exhibits high areal capacity (15 mA h cm-2), high current density (7.5 mA cm-2), and long cycle life (6000 cycles). These results indicate that this interface layer has great potential for practical applications in high-energy-density ASSLMBs.

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