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1.
Front Pharmacol ; 15: 1354806, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601461

RESUMO

Lung injury leads to respiratory dysfunction, low quality of life, and even life-threatening conditions. Circular RNAs (circRNAs) are endogenous RNAs produced by selective RNA splicing. Studies have reported their involvement in the progression of lung injury. Understanding the roles of circRNAs in lung injury may aid in elucidating the underlying mechanisms and provide new therapeutic targets. Thus, in this review, we aimed to summarize and discuss the characteristics and biological functions of circRNAs, and their roles in lung injury from existing research, to provide a theoretical basis for the use of circRNAs as a diagnostic and therapeutic target for lung injury.

3.
J Med Microbiol ; 73(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506717

RESUMO

Purpose. Metagenomic next-generation sequencing (mNGS) has been widely used in the diagnosis of infectious diseases, while its performance in diagnosis of tuberculous meningitis (TBM) is incompletely characterized. The aim of this study was to assess the performance of mNGS in the diagnosis of TBM, and illustrate the sensitivity and specificity of different methods.Methods. We retrospectively recruited TBM patients between January 2021 and March 2023 to evaluate the performance of mNGS on cerebrospinal fluid (CSF) samples, in comparison with conventional microbiological testing, including culturing of Mycobacterium tuberculosis (MTB), acid-fast bacillus (AFB) stain, reverse transcription PCR and Xpert MTB/RIF.Results. Of the 40 enrolled, 34 participants were diagnosed with TBM, including 15(44.12 %) definite and 19(55.88 %) clinical diagnosis based upon clinical manifestations, CSF parameters, brain imaging, pathogen evidence and treatment response. The mNGS method identified sequences of Mycobacterium tuberculosis complex (MTBC) in 11 CSF samples. In patients with definite TBM, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of mNGS were 78.57, 100, 100, 66.67 and 85 %, respectively. Compared to conventional diagnostic methods, the sensitivity of mNGS (78.57 %) was higher than AFB (0 %), culturing (0 %), RT-PCR (60 %) and Xpert MTB/RIF (14.29 %).Conclusions. Our study indicates that mNGS of CSF exhibited an overall improved sensitivity over conventional diagnostic methods for TBM and can be considered a front-line CSF test.


Assuntos
Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Tuberculose Meníngea/diagnóstico , Estudos Retrospectivos , Sequenciamento de Nucleotídeos em Larga Escala , Mycobacterium tuberculosis/genética , Encéfalo
4.
Ecotoxicol Environ Saf ; 274: 116203, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479313

RESUMO

PCDD/Fs are dioxins produced by waste incineration and pose risks to human health. We aimed to detail the health risks of airborne and soil PCDD/Fs near a municipal solid-waste incinerator (MSWI) for the surrounding population and develop a new model that improves upon existing methods. Thus, we conducted field sampling and then investigated a MSWI in the Pearl River Delta (2016-2018). Our results showed that the carcinogenic and non-carcinogenic risk values of PCDD/Fs exposed to residents in nearby areas were acceptable, with hazard index (HI) values lower than 1.0 and a total carcinogenic risk lower than 1.0E-6. Notably, the results raised concerns regarding higher non-carcinogenic risks in children than in adults. Comparative analysis of the frequency accumulation diagram, accumulated probability risk, and the absolute value of error (δ) between the 95% confidence interval (CI) and the 90% CI of the Monte Carlo stochastic simulation-triangular fuzzy number (MCSS-TFN) and the MCSS model, respectively, demonstrated that the MCSS-TFN exhibited less uncertainty than the MCSS model, regardless of the health risk value of PCDD/Fs in ambient air or in soil. This observation underscores the superiority of the MCSS-TFN model over other models in assessing the health risks associated with PCDD/Fs in situations with limited data. Our new method overcomes the limited dataset size and high uncertainty in assessing the health risks of dioxin substances, providing a more comprehensive understanding of their associated health risks than MCSS models.


Assuntos
Poluentes Atmosféricos , Dioxinas , Dibenzodioxinas Policloradas , Adulto , Criança , Humanos , Resíduos Sólidos , Monitoramento Ambiental/métodos , Dibenzodioxinas Policloradas/toxicidade , Dibenzodioxinas Policloradas/análise , Dibenzofuranos , Poluentes Atmosféricos/análise , Incineração , Dioxinas/toxicidade , Medição de Risco , Dibenzofuranos Policlorados/análise , Solo
5.
ACS Appl Mater Interfaces ; 16(6): 7500-7511, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300744

RESUMO

In recent years, organic photonic field-effect transistors have made remarkable progress with the rapid development of conjugated polycrystalline materials. Liquid crystals, with their smooth surface, defined layer thickness, and crystalline structures, are commonly used for these advantages. In this work, a series of smectic liquid crystalline molecules, 2,9-didecyl-dinaphtho-thienothiophene (C10-DNTT), 2,7-didecyl-benzothieno-benzothiopene (C10-BTBT), 3,9-didecyl-dinaphtho-thiophene (C10-DNT), and didecyl-sexithiophene (C10-6T), have been used in photonic transistor memory, functioning as both hole-transport channels and electron traps to investigate systematically the reasons and mechanisms behind the memory behavior of smectic liquid crystals. After thermal annealing, C10-BTBT and C10-6T/C10-DNTT are homeotropically aligned from the smectic A and smectic X phases, respectively. The 3D-ordered structure of these smectic-aligned crystals contributed to efficient photowriting and electrical erasing processes. Among them, the device performance of C10-BTBT was particularly significant, with a memory window of 21 V. The memory ratio could reach 1.5 × 106 and maintain a memory ratio of over 3 orders after 10,000 s, contributing to its smectic A structure. Through the research, we confirmed the memory and light/bias-gated behaviors of these smectic liquid crystalline molecules, attributing them to reversible molecular conformation transitions and the inherent structural inhomogeneity inside the polycrystalline channel layer.

6.
Int J Cardiol ; 400: 131773, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211670

RESUMO

BACKGROUND: High density lipoprotein cholesterol (HDL-C) is considered as "good cholesterol". Recent evidence suggests that a high HDL-C level may increase the risk of poor outcomes in some populations. PURPOSE: To investigate the association between HDL-C levels and poor outcomes in patients after percutaneous coronary intervention (PCI). METHODS: Patients undergoing PCI during January 2012 and December 2018 were consecutively recruited and divided into three groups with different HDL-C levels: HDL-C ≤ 25 mg/dL, 25 < HDL-C ≤ 60 mg/dL, HDL-C > 60 mg/dL by the restricted cubic spline (RCS) analysis and assessed for all-cause mortality (ACM). The association between HDL-C levels and poor outcomes was assessed by multivariable cox regression analysis. RESULTS: The patients were followed with a median duration of 4 years. Of the 7284 participants, 727 all-cause deaths and 334 cardiovascular deaths occurred. A V-shaped association of HDL-C with the prognosis was observed, patients with either excessively low or high HDL-C levels reporting a higher risk than those with midrange values. After adjustment for confounding factors, the former exhibited a higher cumulative rate of ACM and cardiovascular mortality (CM) than the latter [low HDL-C: for ACM, hazard ratio (HR), 1.96; 95%CI, 1.41, 2.73, P < 0.001; for CM, HR, 1.66; 95%CI, 1.03, 2.67; P = 0.037; high HDL-C: for ACM, HR, 1.73; 95%CI, 1.29, 2.32, P < 0.001; for CM, HR, 1.73; 95%CI, 1.16, 2.58; P = 0.007]. CONCLUSION: HDL-C levels display a V-shaped association with poor outcomes in patients after PCI, with excessively high or low HDL-C suggesting a higher mortality risk. An optimal HDL-C level may fall in the range of 25-60 mg/dL.


Assuntos
Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Biomarcadores , Prognóstico , Colesterol , HDL-Colesterol , Fatores de Risco
7.
J Synchrotron Radiat ; 31(Pt 2): 252-259, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241123

RESUMO

In this study, a combination of X-ray excited optical luminescence (XEOL), time-resolved XEOL (TR-XEOL) and the Hanbury-Brown and Twiss (HB-T) interferometer at the Taiwan Photon Source (TPS) 23A X-ray nanoprobe beamline for exploring quantum materials is demonstrated. On the basis of the excellent spatial resolution rendered using a nano-focused beam, emission distributions of artificial micro-diamonds can be obtained by XEOL maps, and featured emission peaks of a selected local area can be obtained by XEOL spectra. The hybrid bunch mode of the TPS not only provides a sufficiently high peak power density for experiments at each beamline but also permits high-quality temporal domain (∼200 ns) measurements for investigating luminescence dynamics. From TR-XEOL measurements, the decay lifetime of micro-diamonds is determined to be approximately 16 ns. Furthermore, the XEOL spectra of artificial micro-diamonds can be investigated by the HB-T interferometer to identify properties of single-photon sources. The unprecedented strategy of combining XEOL, TR-XEOL and the HB-T interferometer at the X-ray nanoprobe beamline will open new avenues with significant characterization abilities for unraveling the emission mechanisms of single-photon sources for quantum materials.

8.
Small ; : e2307774, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200683

RESUMO

Tin (Sn)-based perovskites are being investigated in many optoelectronic applications given their similar valence electron configuration to that of lead-based perovskites and the potential environmental hazards of lead-based perovskites. However, the formation of high-quality Sn-based perovskite films faces several challenges, mainly due to the easy oxidation of Sn2+ to Sn4+ and the fast crystallization rate. Here, to develop an environmentally friendly process for Sn-based perovskite fabrication, a series of natural antioxidants are studied as additives and ascorbic acid (VitC) is found to have a superior ability to inhibit the oxidation problem. A common cyclic molecule, 18-Crown-6, is further added as a second additive, which synergizes with VitC to significantly reduce the nonradiative recombination pathways in the PEA2 SnI4 film. This synergistic effect greatly improves the performance of 2D red Sn-based PeLED, with a maximum external quantum efficiency of 1.87% (≈9 times that of the pristine device), a purer color, and better bias stability. This work demonstrates the potential of the dual-additive approach in enhancing the performance of 2D Sn-based PeLEDs, while the use of these environmentally friendly additives contributes to their future sustainability.

9.
ACS Biomater Sci Eng ; 10(2): 1128-1138, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38221709

RESUMO

The physiological state of the human body can be indicated by analyzing the composition of sweat. In this research, a fluorescence-recovered wearable hydrogel patch has been designed and realized which can noninvasively monitor the glucose concentration in human sweat. Rare-earth nanoparticles (RENPs) of NaGdF4 doped with different elements (Yb, Er, and Ce) are synthesized and optimized for better luminescence in the near-infrared second (NIR-II) and visible region. In addition, RENPs are coated with CoOOH of which the absorbance has an extensive peak in the visible and NIR regions. The concentration of H2O2 in the environment can be detected by the fluorescence recovery degree of CoOOH-modified RENPs based on the fluorescence resonance energy transfer effect. For in vivo detection, the physiological state of oxidative stress at tumor sites can be visualized through its fluorescence in NIR-II with low background noise and high penetration depth. For the in vitro detection, CoOOH-modified RENP and glucose oxidase (GOx) were doped into a polyacrylamide hydrogel, and a patch that can emit green upconversion fluorescence under a 980 nm laser was prepared. Compared with the conventional electrochemical detection method, the fluorescence we presented has higher sensitivity and linear detection region to detect the glucose. This improved anti-interference sweat patch that can work in the dark environment was obtained, and the physiological state of the human body is conveniently monitored, which provides a new facile and convenient method to monitor the sweat status.


Assuntos
Cobalto , Metais Terras Raras , Nanopartículas , Óxidos , Dispositivos Eletrônicos Vestíveis , Humanos , Fluorescência , Glucose , Hidrogéis , Peróxido de Hidrogênio , Metais Terras Raras/química , Nanopartículas/química
10.
J Infect Chemother ; 30(6): 544-547, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37992864

RESUMO

Streptococcus suis is a pathogen of emerging zoonotic diseases and meningoencephalitis is the most frequent clinical symptom of S. suis infection in humans. Rapid diagnosis of S. suis meningoencephalitis is critical for the treatment of the disease. While the current routine microbiological tests including bacterial culture and gram staining are poorly sensitive, diagnosis of S. suis meningoencephalitis by metagenomic next-generation sequencing (mNGS) has been rarely reported. Here, we report a 52-year-old female pork food producer with a broken finger developed S. suis meningoencephalitis. After her admission, no pathogenic bacteria were detected through bacterial culture and Gram staining microscopy in the cerebrospinal fluid obtained via lumbar puncture. However, mNGS identified the presence of S. suis in the sample. mNGS is a promising diagnostic tool for rapid diagnosis of rare infectious diseases in the central nervous system.

11.
Technol Health Care ; 32(2): 705-718, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37483032

RESUMO

BACKGROUND: With improving living standards, the incidence of cervical spondylotic myelopathy (CSM) has become increasingly high. OBJECTIVE: The study aims to explore the effect of diversified health-promoting models on rehabilitation exercises in patients with CSM after an operation. METHOD: This was a randomized controlled trial, wherein 107 patients with CSM treated by neurosurgery were selected as the subjects. Of those, 52 patients in the control group adopted the conventional health-promoting model, while the remaining 55 patients in the intervention group adopted diversified health-promoting models. The effect of rehabilitation exercises in the two groups was evaluated according to the self-efficacy rehabilitation outcome scale, grip strength measurement of the affected limb, and Barthel index. RESULTS: At Day 3 post-operation and before discharge, the self-efficacy management of rehabilitation exercises in the intervention group was better than that of the control group (P< 0.05). The grip strength measurement of the affected limb, Japanese Orthopedic Association score of the cervical vertebra, and Barthel index of the two groups at Day 3 post-operation were lower than before the intervention and were not statistically significant (P> 0.05). However, these three items before discharge were improved when compared with those of before intervention and were statistically significant (P< 0.05). CONCLUSION: Postoperative rehabilitation exercises guided by the diversified health-promoting models for patients with CSM can improve the patients' self-efficacy management ability in rehabilitation exercises, help improve grip strength, and promote the recovery of cervical vertebra function, thereby improving the patients' quality of life.


Assuntos
Doenças da Medula Espinal , Espondilose , Humanos , Qualidade de Vida , Espondilose/cirurgia , Espondilose/complicações , Doenças da Medula Espinal/cirurgia , Doenças da Medula Espinal/etiologia , Vértebras Cervicais/cirurgia , Resultado do Tratamento , Terapia por Exercício
12.
Microbiol Spectr ; 12(1): e0224623, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38047697

RESUMO

IMPORTANCE: Tuberculous meningitis is a life-threatening infection with high mortality and disability rates. Current diagnostic methods using cerebrospinal fluid (CSF) samples have limited sensitivity and lack predictive biomarkers for evaluating prognosis. This study's findings reveal excessive activation of the immune response during tuberculous meningitis (TBM) infection. Notably, a strong negative correlation was observed between CSF levels of monokine induced by interferon-γ (MIG) and the CSF/blood glucose ratio in TBM patients. MIG also exhibited the highest area under the curve with high sensitivity and specificity. This study suggests that MIG may serve as a novel biomarker for differentiating TBM infection in CSF or serum, potentially leading to improved diagnostic accuracy and better patient outcomes.


Assuntos
Tuberculose Meníngea , Humanos , Tuberculose Meníngea/diagnóstico , Tuberculose Meníngea/tratamento farmacológico , Curva ROC , Interferon gama , Soro , Biomarcadores , Líquido Cefalorraquidiano
13.
Acta Pharmaceutica Sinica ; (12): 84-93, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1005427

RESUMO

Fraction absorbed (Fa) is an important parameter to describe the absorption level of oral drugs, and an important basis for the development and optimization of the formulation process. Because it is easily confused with the concept of absolute bioavailability, it has not received enough attention from the industry. There are many complex factors affecting Fa. There are three time-related factors that directly affect the extent of Fa: the release time, the absorption time, and the residence time. The relationship between these three time-related factors determines the extent of Fa. Generally, we are more concerned about the apparent factors that affect the extent of Fa, including independent variables and covariates; The independent variables include administered dose, route, dosage form, etc. The covariates are divided into internal and external factors, and external factors include food factors, drug interactions, etc. Internal causes include age, sex, disease, etc. This paper analyzes and systematically combs how independent variables and covariates directly or indirectly affect the three time-related factors by affecting the body's physiology and internal environment, thus changing the complex process of Fa. Understanding this theoretical framework can better optimize the independent variables to reduce the impact of covariates on Fa. In addition, this paper also introduces the latest progress of prediction and evaluation of Fa, including the progress of complex dissolution device and the status of software prediction.

14.
Opt Express ; 31(25): 41864-41874, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087574

RESUMO

We report a theoretical investigation of X-ray back diffraction at grazing incidence. Based on the framework of the dynamical theory of X-ray diffraction, the grazing incidence for Si (12 4 0) back diffraction is taken as an example to resolve the eigenvalue problem inside the crystal. The dispersion surface and the resulting diffraction intensities are strongly affected by the miscut angle as well as the diffraction geometry of grazing incidence. The kinematical relationship between the incident angle and the miscut angle is well explained by Snell's law. While only the two-beam diffraction is considered, our treatment can be further extended to include the cases for multiple diffractions as well.

15.
ACS Appl Mater Interfaces ; 15(42): 49379-49389, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37842834

RESUMO

Cr-doped inorganic materials are pivotal in developing near-infrared optical materials; however, multivalent Cr ions and their respective distribution in the materials remain ambiguous. Herein, a series of Li(Sc1-xInx)O2:Cr phosphors containing both Cr3+/Cr6+ ions are prepared. High-resolution synchrotron X-ray diffraction (XRD) reveals two similar phases in Li(Sc1-xInx)O2. Raman spectra further confirm distinct scattering patterns for the two end-member compositions, corroborating the findings from the synchrotron XRD analysis. Cr K-edge X-ray absorption near-edge structure and extended X-ray absorption fine structure demonstrate that most Cr ions in the as-prepared samples are Cr6+, while Cr3+ becomes dominant after washing with water. Moreover, the source and distribution of Cr3+ and Cr6+ ions in the as-prepared and washed samples are revealed through X-ray fluorescence and X-ray excited optical luminescence techniques, which indicate that Cr6+ ions aggregate within the sample, while Cr3+ ions are evenly distributed. Photoluminescence, decay curves, and line shape analyses are implemented to resolve the electron-lattice interactions, and the corresponding mechanisms are provided to explain the asymmetry between photoluminescence and photoluminescence excitation spectra. Overall, this study provides valuable insights into the distribution of low-concentration multivalence ions in solid-state materials and offers a deeper understanding of the approaches to precisely resolve the subtle changes in the crystal structure.

16.
Huan Jing Ke Xue ; 44(10): 5813-5822, 2023 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-37827796

RESUMO

Soil acidification and low SOC are the main limiting factors in acidic paddy soils. Straw returning with lime is an effective measure to alleviate soil acidification and improve soil fertility; however, its interaction effects on SOC and carbon pool management are still unclear. To investigate the impact of straw returning with lime on the organic carbon pool of acidic paddy soil, field experiments were conducted on acidic paddy soil in Baiyun District and Huiyang District of Guangdong Province. The changes in soil total organic carbon (TOC), water-soluble organic carbon (DOC), active organic carbon (LOC), particulate organic carbon (POC), microbial biomass carbon (MBC), carbon pool index (CPI), stable organic carbon (IOC), carbon pool activity (L), carbon pool activity index (CPAI), and carbon pool management index (CPMI) were analyzed under three treatments (CK, conventional fertilization; RS, straw returning+conventional fertilization; RS+L straw returning with lime+conventional fertilization). The results demonstrated that compared with that in CK, the TOC, LOC, POC, and MBC in the RS+L treatment were significantly increased by 10.24%-17.79%, 34.49%-44.37%, 19.27%-23.59%, and 33.36%-43.26%, respectively (P<0.05). Compared with that in CK, the RS+L treatment significantly increased the DOC content during the early growth stage (15-45 days after transplanting) of rice (P<0.05) but had no significant influence on the DOC content during the late growth stage of rice. Compared with that in RS, the TOC, LOC, POC, and MBC in the RS+L treatment were increased by 2.15%-6.95%, 1.17%-17.90%, 4.27%-8.65%, and 12.99%-14.53%, respectively. Compared with that in CK, the RS+L treatment significantly increased IOC and CPI by 8.32%-15.57% and 14.00%-20.00%, respectively (P<0.05). Compared with that in the CK treatment, the RS treatment significantly increased CPI by 14.00%-18.00% (P<0.05). No significant differences in L, CPAI, or CPMI were detected among the different treatments. The soil pH in the RS+L treatment was significantly higher than that in the CK treatment (P<0.05). No significant differences in rice yield were detected among the different treatments. Principal component analysis demonstrated that rice yield was primarily correlated with DOC, LOC, CPAI, and CPMI but its contribution to SOC and carbon pool management index was low. Principal component analysis also indicated that straw returning with lime could improve soil pH and nutrient contents of acidic paddy soil, driving the formation and accumulation of organic carbon fraction such as MBC and POC, thus boosting the increase in SOC. In conclusion, straw returning with lime is beneficial to the accumulation of MBC, POC, LOC, and IOC in acidic paddy soil to improve the content and stability of soil total organic carbon, which is an effective way to improve the carbon sequestration of acidic paddy soil.

17.
ACS Appl Mater Interfaces ; 15(39): 46157-46170, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37728642

RESUMO

The vision-inspired artificial neural network based on optical synapses has drawn a tremendous amount of attention for emulating biological senses. Although photoexcitation-induced synaptic functionalities have been widely studied, optical habituation via the photoinhibitory pathway is yet to be demonstrated for sophisticated biomimetic visual adaptive systems. Here, the first optical neuromorphic block copolymer (BCP) phototransistor is demonstrated as an all-optical operation responding to various wavelengths, fulfilling photoassisted dynamic learning/forgetting cycles via optical potentiation without gate bias. The polyfluorene BCPs were precisely designed to enable wavelength-adaptive responses, benefiting from interfacial semiconductor/electret morphology and the crystallinity/electron affinity of the BCPs. Notably, this is the first work to simultaneously exhibit fully light-controlled short- and long-term memory based on organic material systems. The device presents a high current contrast above 100-fold and long-term retention over 104 s. As a proof-of-concept for neural networks, a 6 × 6 array of photosynapses performed outstanding visual pattern learning/forgetting with high accuracy. This study exploits the design strategy of a conjugated BCP electret to unleash the full potential of wavelength-adaptive visual neuroplasticity transitions. It provides an effective architecture for designing high-performance and high-storage capacity required applications in next-generation neuromorphic systems.

18.
Macromol Rapid Commun ; 44(24): e2300382, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37703910

RESUMO

Organic-inorganic hybrid perovskites have garnered significant attention in optoelectronics owing to their outstanding tunable optical characteristics. Controlled growth of perovskite nanocrystals from solutions is key for controlling the emission intensity and photoluminescence lifetime of perovskites. In particular, most studies have focused on controlling the crystallization of perovskite through chemical treatment using chelating ligands or physical treatment via antisolvent diffusion, and there exists a trade-off between the photoluminescence intensity and lifetime of perovskites. Herein, a selective solvent vapor-assisted crystallization with the aid of a functional polymer, which nanoscale perovskite crystals are grown andante from precursor solution, is presented for tuning the crystallization and optical properties of a common halide perovskite, methylammonium lead bromide (MAPbBr3 ). The proposed method here produces perovskite nanocrystals in the range of 200-300 nm. The spin-coated thin film formed from the perovskite solution exhibits strong green photoluminescence with a long lifetime. The effects of the functional group and polymer dosage on the crystallization of MAPbBr3 are systematically investigated, and the crystallization mechanism is explained based on a modified LaMer model. This study provides an advanced solution process for precisely controlling perovskite crystallization to enhance their optical properties for next-generation optoelectronic devices.


Assuntos
Compostos de Cálcio , Gases , Cristalização , Difusão
19.
Phys Chem Chem Phys ; 25(37): 25639-25653, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721171

RESUMO

In the present study, synchrotron-based X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS) and X-ray excited optical luminescence (XEOL) have been used to investigate the induced defect states in metal oxide nanomaterials. Specifically, two synthesis approaches have been followed to develop unique nano-sized peanut-shaped (N-ZnO) nanostructures and micron-sized hexagonal rods (M-ZnO). XANES analysis at the Zn K-edge revealed the presence of defect states with a divalent oxidation state of zinc (Zn2+) in a tetrahedral structure. Furthermore, XAS measurements performed at the Zn L3,2-edge and O K-edge confirm higher oxygen-related defects in M-ZnO, while N-ZnO appeared to have a higher concentration of surface defects due to size confinement. Moreover, the in-line XEOL and time dependent-XEOL measurements exposed the radiative excitonic recombination phenomena occurring in the band-tailing region as a function of absorption length, X-ray energy excitation, and time. Based on the chronology developed in the defect state improvement, a possible energy band diagram is proposed to accurately locate the defect states in the two systems. Furthermore, the increased absorption intensity at the Zn L3,2-edge and the O K-edge under the UV lamp suggests delayed recombination of electrons and holes, highlighting their potential use as photo catalysts. The photocatalytic activity degrading the rhodamine B dye established M-ZnO as a superior catalyst with a rapid degradation rate and significant mineralization. Overall, this work provides valuable insights into ZnO defect states and provides a foundation for efficient advanced materials for environmental or other optoelectronic applications.

20.
Cardiovasc Diabetol ; 22(1): 198, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537553

RESUMO

BACKGROUND: Early identification of populations at high cardiovascular disease (CVD) risk and improvement of risk factors can significantly decrease the probability of CVD development and improve outcomes. Insulin resistance (IR) is a CVD risk factor. The triglyceride glucose (TyG) index is a simple and reliable index for evaluating IR. However, no clinical studies on the prognostic value of the TyG index in a high risk CVD population have been conducted. This study evaluated the relationship between the TyG index and prognosis in a high risk CVD population. METHODS: This study enrolled 35,455 participants aged 35-75 years who were at high CVD risk and visited selected health centers and community service centers between 2017 and 2021. Their general clinical characteristics and baseline blood biochemical indicators were recorded. The TyG index was calculated as ln[fasting triglyceride (mg/dl)× fasting blood glucose (mg/dl)/2]. The endpoints were all-cause death and cardiovascular death during follow-up. Cox proportional hazard models and restricted cubic spline (RCS) analysis were used to evaluate the correlation between the TyG index and endpoints. RESULTS: In the overall study population, the mean age of all participants was 57.9 ± 9.6 years, 40.7% were male, and the mean TyG index was 8.9 ± 0.6. All participants were divided into two groups based on the results of the RCS analysis, with a cut-off value of 9.83. There were 551 all-cause deaths and 180 cardiovascular deaths during a median follow-up time of 3.4 years. In the multivariate Cox proportional hazard model, participants with a TyG index ≥ 9.83 had a higher risk of all-cause death (Hazard ratio [HR] 1.86, 95% Confdence intervals [CI] 1.37-2.51, P<0.001) and cardiovascular death (HR 2.41, 95%CI 1.47-3.96, P = 0.001) than those with a TyG index < 9.83. Subgroup analysis revealed that there was no interaction between the TyG index and variables in all subgroup analyses. CONCLUSIONS: The high TyG index was associated with an increased risk of all-cause death and cardiovascular death in people at high risk of CVD. This finding demonstrates the value of the TyG index in the primary prevention of CVD. TRIAL REGISTRATION: retrospectively registered, the registration number is K2022-01-005 and the date is 2022.01.30.


Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Prognóstico , Glucose , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Triglicerídeos , Glicemia/análise , Biomarcadores , Fatores de Risco , Medição de Risco
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