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1.
Inorg Chem ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445543

RESUMO

For the first time, nanotubes of Y3Ga5O12:Cr3+ (referred to as YGO:Cr3+) and Y3Ga5O12:Cr3+/Yb3+ (referred to as YGO:Cr3+/Yb3+) were produced via a single-needle electrospinning method. The nanotubes of YGO:Cr3+ and YGO:Cr3+/Yb3+ have outer diameters between 190 and 210 nm, whereas the inner diameter ranges between 70 and 80 nm, and the wall thickness ranges from 50 to 60 nm. The temperature sensitivity of YGO:0.02Cr3+ nanotubes was examined by studying how the Cr3+ lifetime changes with temperature. In the temperature range of 303 to 723 K, the peak values of Sa and Sr were 0.274 and 0.0067 K-1, respectively. Temperature sensing properties of YGO:0.02Cr3+/yYb3+ (y = 0.01, 0.02, and 0.05) nanotubes were evaluated via the FIR technique utilizing nonthermally coupled energy levels. The I970/I708 in the YGO:0.05Cr3+/0.01Yb3+ nanotubes displayed a maximal Sr value of 0.013 K-1 at 633 K, which exceeds that of other Cr3+-doped NIR phosphors previously reported and is promising for high-temperature measurements.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 327: 125285, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39461084

RESUMO

Eu3+-activated materials have garnered significant attention due to their outstanding optical characteristics. In this work, the sol-gel method was successfully used to prepare Bi2Mo3O12 phosphors doped with different amounts of Eu3+. The generated samples were identified as orthorhombic Bi2Mo3O12 with a scheelite-like structure by X-ray diffraction analysis of the crystal structure. The sample's morphology and size were examined using scanning electron microscopy and transmmission electron microscopy, which revealed irregular block morphology and tens to hundreds nanometers scale dimension. From the analysis of the concentration-dependent luminescence intensity of Eu3+, it was confirmed that the exchange interaction was responsible for the quenching of 5D0 fluorescence of Eu3+. When excited at 374 nm, the phosphor emitted brilliant red light, with the highest emission occurring at 616 nm (5D0→7F2 transition), and the calculated color coordinates of the sample were (0.663, 0.336). By examining the temperature dependence of the emission spectra, the temperature sensing performance of the sample and the thermal quenching behavior of Eu3+ luminescence was explored. Furthermore, the optical transition property of Eu3+ was investigated by using the emission spectra and fluorescence lifetime within the context of Judd-Ofelt theory. Ultimately, latent fingerprint visualization of the sample on various object surfaces was studied, thanks to the intense luminescence and small particle size of the Bi2Mo3O12:Eu3+ phosphor. The results indicated that the sample can clearly display the different hierarchical features of fingerprint on different object surfaces.

3.
Cell Transplant ; 33: 9636897241270401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39219184

RESUMO

The annual number of human leukocyte antigen (HLA)-haploidentical allogeneic hematopoietic stem cell transplantation (haplo-HCT) is increasing steadily. Comparative studies about haplo-HCT versus HCT with HLA-matched sibling donors (MSD-HCT) have been tried in acute myeloid leukemia and B-cell acute lymphoblastic leukemia/lymphoma (ALL). Few studies were reported in adult T-cell ALL (T-ALL). In this retrospective study, a total of 88 consecutive patients with T-ALL were enrolled who underwent MSD-HCT (n = 24) and haplo-HCT (n = 64) with antithymocyte globulin (ATG)-based graft versus host disease (GVHD) prophylaxis between 2010 and 2022. Median follow-up for survivors was similar (43.5 [range: 7-88] months for MSD-HCT versus 43.5 (range: 6-144) months in the Haplo-HCT group). The 100-day cumulative incidence of grade II to IV acute GVHD (aGVHD) was similar, 33% (95% confidence interval [CI], 16%-52%) after MSD-HCT versus 44% (95% CI, 31%-55%) after haplo-HCT, P = 0.52. The cumulative incidences of grade III-IV aGVHD were 8% (95% CI, 1%-23%) in the MSD-HCT group and 5% (95% CI, 1%-12%) in the haplo-HCT group (P = 0.50). The 2-year cumulative incidence of chronic GVHD (limited and extensive) in the haplo-HCT, 11% (95% CI, 5%-20%) was significantly lower than that in the MSD-HCT group (42% [95% CI, 21%-62%], P = 0.002). The cumulative incidence of 4-year relapse rates (44% versus 37%, P = 0.56) and non-relapse mortality (7% versus 21%, P = 0.08) did not differ between these two groups. There were also no differences in 4-year overall survival (46% versus 47%, P = 0.44) and progression-free survival (49% versus 42%, P = 0.45) between these two groups. On multivariate analysis, using busulfan/fludarabine (BU/Flu) conditioning regimen was found to be associated with worse clinical outcome. Our results suggested that ATG-based haplo-HCT platform could work as an alternative to MSD-HCT for adult patients with T-ALL. Compared with MSD-HCT, haplo-HCT might carry a low risk for cGVHD.


Assuntos
Soro Antilinfocitário , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Irmãos , Humanos , Adulto , Feminino , Masculino , Soro Antilinfocitário/uso terapêutico , Pessoa de Meia-Idade , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Adulto Jovem , Estudos Retrospectivos , Transplante Haploidêntico/métodos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/métodos , Doença Crônica
4.
Dalton Trans ; 53(40): 16530-16540, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39324955

RESUMO

Cubic and hexagonal structured SrTa4O11(STO):Er3+/Yb3+ phosphors were synthesized by a solid state reaction (SSR) and molten salt synthesis (MSS). The upconversion luminescence (UCL) intensity of these samples was investigated. Hexagonal STO:Er3+/Yb3+ with much or a little ß-Ta2O5 can be synthesized by SSR in air or vacuum, respectively, and the UCL intensity of the sample synthesized by SSR in a vacuum is higher. Cubic STO:Er3+/Yb3+ can be synthesized by MSS with KCl flux, and hexagonal STO:Er3+/Yb3+ can be synthesized by MSS with B2O3 flux, which has the strongest UCL intensity among all the samples compared with samples prepared by SSR. The sample by MSS with B2O3 flux was acid pickled (AP) with HCl solution, and the green UCL intensity increased by 2.18 times, which reached 32.95% for ß-NaYF4:Er3+/Yb3+. The UCL intensity of the hexagonal STO:Er3+/Yb3+ is much higher than that of the cubic structure, which is due to the layered structure and the non-central symmetry of the Er3+/Yb3+ doped sites in hexagonal STO:Er3+/Yb3+. The temperature sensitivity of samples is evaluated by luminescence intensity ratio (LIR) technology. The maximum relative sensitivity is 0.0099 K-1 at 303 K. All the results show that hexagonal STO:Er3+/Yb3+ has excellent pure green UCL intensity and high temperature sensitivity, which can be used in UCL display and temperature sensing.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 326: 125219, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39348739

RESUMO

The low photoluminescence quantum yield (PLQY) of CsPbCl3 perovskite quantum dots (PQDs) poses a significant challenge to their application as ion detection probes. To address this issue, we enhanced the PLQY of CsPbCl3 PQDs through Mn doping. These enhanced PQDs were then employed as probes for the highly sensitive detection of Cu2+ ions and temperature. CsPbCl3:Mn PQDs with varying Mn/Pb ratios were synthesized via hot injection. The Mn doping introduced an emission band near 600 nm, with intensity increasing alongside doping concentration. At an Mn/Pb ratio of 2.0, the PLQY was enhanced nearly tenfold, from 5.46 % for undoped CsPbCl3 to 52.48 % for CsPbCl3:Mn. CsPbCl3:Mn PQDs with the highest PLQY were employed as luminescent probes, utilizing the fluorescence intensity ratio (FIR) technique for copper detection and temperature sensing. The experimental results demonstrated a linear relationship between the FIR and Cu2+ concentration over the range of 22.12 nM-1600 nM, with 22.12 nM being the calculated limit of detection. Analysis of the emission spectra and fluorescence lifetimes at varying Cu2+ concentrations revealed that electron transfer from CsPbCl3 to Cu2+ induced fluorescence quenching. CsPbCl3:Mn exhibits a high relative sensitivity of 15.89 % K-1 at 298 K, along with excellent reversibility. These findings highlight the potential application of CsPbCl3:Mn PQDs in both temperature sensing and the analysis of wear metals in engine lubricating oils.

6.
Sensors (Basel) ; 24(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39338626

RESUMO

In this study, we present an electronic nose (e-nose) humidity compensation system based on rapid detection to solve the issue of humidity drift's potential negative impact on the performance of electronic noses. First, we chose the first ten seconds of non-steady state (rapid detection mode) sensor data as the dataset, rather than waiting for the electronic nose to stabilize during the detection process. This was carried out in the hope of improving the detection efficiency of the e-nose and to demonstrate that the e-nose can collect gasses efficiently in rapid detection mode. The random forest approach is then used to optimize and reduce the dataset's dimensionality, filtering critical features and improving the electronic nose's classification capacity. Finally, this study builds an electronic nose humidity compensation system to compensate for the datasets generated via rapid real-time detection, efficiently correcting the deviation of the sensor response caused by humidity variations. This method enhanced the average resolution of the electronic nose in this trial from 87.7% to 99.3%, a 12.4% improvement, demonstrating the efficacy of the humidity compensation system based on rapid detection for the electronic nose. This strategy not only improves the electronic nose's anti-drift and classification capabilities but also extends its service life, presenting a new solution for the electronic nose in practical detecting applications.

7.
Mikrochim Acta ; 191(9): 553, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167246

RESUMO

Single-level biomarker detection has the limitation of insufficient accuracy in cancer diagnosis. Therefore, the strategy of developing highly sensitive, multi-channel biosensors for high-throughput ctDNA determination is critical to improve the accuracy of early diagnosis of clinical tumors. Herein, in order to achieve efficient detection of up to ten targets for early diagnosis of ovarian cancer, a DNA-nanoswitch-based multi-channel (DNA-NSMC) biosensor was built based on the multi-module catalytic hairpin assembly-mediated signal amplification (CHA) and toehold-mediated DNA strand displacement (TDSD) reaction. Only two different fluorescence signals were used as outputs, combined with modular segmentation strategy of DNA-nanoswitch-based reaction platform; the multi-channel detection of up to ten targets was successfully achieved for the first time. The experimental results suggest that the proposed biosensor is a promising tool for simultaneously detecting multiple biomarkers for the early diagnosis of ovarian cancer, offering new strategies for the early screening, diagnosis, and treatment not only for ovarian cancer but also for other cancers.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , DNA Tumoral Circulante , Neoplasias Ovarianas , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/sangue , Feminino , Humanos , Técnicas Biossensoriais/métodos , Biomarcadores Tumorais/sangue , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , Limite de Detecção
8.
Inorg Chem ; 63(30): 14152-14161, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38995295

RESUMO

The influence of cooling history for the Zn3Ga2Ge2O10/Cr3+ phosphors prepared by solid state reaction on the spectral properties was discovered, and an anticounterfeiting scheme based on the identification with smartphone was proposed and experimentally demonstrated using the studied phosphors. A combination of color-tunable visible fluorescence emission and near-infrared (NIR) afterglow emission in Zn3Ga2Ge2O10/x mol % Cr3+(x = 0, 0.05, 1, 2, 3, and 4) phosphors to achieve multimode anticounterfeiting was reported. It is found that with the increasing Cr3+ concentrations, the visible emission can be tuned from green, light pink, and light red to deep red under 254 nm ultraviolet (UV) excitation. This phenomenon is related to the formation of oxygen vacancies in the host during the process of natural cooling and the characteristic emission of Cr3+. In addition, the persistent time of the Cr3+ emission centered at 700 nm can be also tuned by various Cr3+ concentrations. A possible mechanism was deduced to explain the afterglow phenomenon. Lastly, a flower pattern applied in anticounterfeiting was fabricated using the Zn3Ga2Ge2O10/x mol % Cr3+ (x = 0, 0.05, 1, 2, 3, and 4) phosphors to present tunable color and NIR afterglow signals at different excitation modes, and the camera of smartphone was chosen as a detection tool to take the NIR images. The results obtained above suggest that the prepared phosphors at natural cooling condition have great potential in affording advanced optical anticounterfeiting.

9.
Int Immunopharmacol ; 137: 112493, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897126

RESUMO

Microglia-mediated neuroinflammation is closely associated with many neurodegenerative diseases. Psoralen has potential for the treatment of many diseases, however, the anti-neuroinflammatory and neuroprotective effects of psoralen have been unclear. This study investigated the anti-neuroinflammatory and neuroprotective effects of psoralen and its regulation of microglial M1/M2 polarization. The LPS-induced mice model was used to test anti-neuroinflammatory effects, regulatory effects on microglia polarization, and neuroprotective effects of psoralen in vivo. The LPS-induced BV2 model was used to test the anti-neuroinflammatory effects and the regulatory effects and mechanisms on microglial M1/M2 polarization of psoralen in vitro. PC12 cell model induced by conditioned medium of BV2 cells was used to validate the protective effects of psoralen against neuroinflammation-induced neuronal damage. These results showed that psoralen inhibited the expression of iNOS, CD86, and TNF-α, and increased the expression of Arg-1, CD206, and IL-10. These results indicated that psoralen inhibited the M1 microglial phenotype and promoted the M2 microglial phenotype. Further studies showed that psoralen inhibited the phosphorylation of Fyn and PKCδ, thereby inhibiting activation of the MAPKs and NF-κB pathways and suppressing the expression of pro-inflammatory cytokines in microglia. Furthermore, psoralen reduced oxidative stress, neuronal damage, and apoptosis via inhibition of neuroinflammation. For the first time, this study showed that psoralen protected neurons and alleviated neuroinflammation by regulating microglial M1/M2 polarization, which may be mediated by inhibition of the Fyn-PKCδ pathway. Thus, psoralen may be a potential agent in the treatment of neuroinflammation-related diseases.


Assuntos
Ficusina , Lipopolissacarídeos , Microglia , Doenças Neuroinflamatórias , Neurônios , Fármacos Neuroprotetores , Proteína Quinase C-delta , Proteínas Proto-Oncogênicas c-fyn , Transdução de Sinais , Animais , Microglia/efeitos dos fármacos , Microglia/metabolismo , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Proteína Quinase C-delta/metabolismo , Camundongos , Ficusina/farmacologia , Ficusina/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/imunologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Masculino , Camundongos Endogâmicos C57BL , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo
10.
Sci Total Environ ; 935: 173323, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777058

RESUMO

The extensive utilization of antibiotics has resulted in their frequent detection, contributing to an increased abundance of antibiotic resistance genes in rivers and posing a significant threat to environmental health. Particulate matter plays a crucial role as the primary carrier of various pollutants in river ecosystem. Its physicochemical properties and processes of sedimentation and re-suspension can influence the migration and transformation of antibiotics, yet the mechanisms of this impact remain unclear. In this study, we investigated the distribution characteristics at the micro-scale of particles in the upstream plain river network of the Taihu basin and the adsorption behaviors of antibiotics in particulate matter. The results revealed that particles were predominantly in the size range of 30 to 150 µm in the river network and highest total antibiotic concentrations in 0 to 10 µm particle size fractions. Adsorption experiments also confirmed that the smaller the suspended particle size, the stronger the adsorption capacity for antibiotics. Spatially, both the average particle size and total antibiotic concentrations were lower downstream than upstream. The distribution mechanism of antibiotic in river network sediments was significantly influenced by frequent resuspension and settling of fine particles with a stronger capacity to adsorb antibiotics under hydrodynamic conditions. This ultimately facilitated the release of antibiotics from sediment into the water, resulting in lower antibiotic concentrations in downstream sediments relative to upstream These findings suggest that fine particles serve as the primary carriers of antibiotics, and their sorting and transport processes can significantly influence the distribution of antibiotics in water-sediment systems. This study enhances our understanding of the migration mechanisms of antibiotics in river networks and will prove beneficial for the development of management strategies aimed at controlling antibiotic dissemination.


Assuntos
Antibacterianos , Monitoramento Ambiental , Material Particulado , Rios , Poluentes Químicos da Água , Rios/química , Antibacterianos/análise , Material Particulado/análise , Poluentes Químicos da Água/análise , China , Tamanho da Partícula
11.
Proc Natl Acad Sci U S A ; 121(22): e2319880121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768353

RESUMO

Elevated interstitial fluid pressure (IFP) within pathological tissues (e.g., tumors, obstructed kidneys, and cirrhotic livers) creates a significant hindrance to the transport of nanomedicine, ultimately impairing the therapeutic efficiency. Among these tissues, solid tumors present the most challenging scenario. While several strategies through reducing tumor IFP have been devised to enhance nanoparticle delivery, few approaches focus on modulating the intrinsic properties of nanoparticles to effectively counteract IFP during extravasation and penetration, which are precisely the stages obstructed by elevated IFP. Herein, we propose an innovative solution by engineering nanoparticles with a fusiform shape of high curvature, enabling efficient surmounting of IFP barriers during extravasation and penetration within tumor tissues. Through experimental and theoretical analyses, we demonstrate that the elongated nanoparticles with the highest mean curvature outperform spherical and rod-shaped counterparts against elevated IFP, leading to superior intratumoral accumulation and antitumor efficacy. Super-resolution microscopy and molecular dynamics simulations uncover the underlying mechanisms in which the high curvature contributes to diminished drag force in surmounting high-pressure differentials during extravasation. Simultaneously, the facilitated rotational movement augments the hopping frequency during penetration. This study effectively addresses the limitations posed by high-pressure impediments, uncovers the mutual interactions between the physical properties of NPs and their environment, and presents a promising avenue for advancing cancer treatment through nanomedicine.


Assuntos
Sistemas de Liberação de Medicamentos , Líquido Extracelular , Nanopartículas , Pressão , Nanopartículas/química , Líquido Extracelular/metabolismo , Animais , Sistemas de Liberação de Medicamentos/métodos , Camundongos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Linhagem Celular Tumoral , Extravasamento de Materiais Terapêuticos e Diagnósticos , Simulação de Dinâmica Molecular , Antineoplásicos/farmacocinética , Antineoplásicos/administração & dosagem , Antineoplásicos/química
12.
Environ Res ; 252(Pt 2): 118841, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582418

RESUMO

The significant threat of antibiotic resistance genes (ARGs) to aquatic environments health has been widely acknowledged. To date, several studies have focused on the distribution and diversity of ARGs in a single river while their profiles in complex river networks are largely known. Here, the spatiotemporal dynamics of ARG profiles in a canal network were examined using high-throughput quantitative PCR, and the underlying assembly processes and its main environmental influencing factors were elucidated using multiple statistical analyses. The results demonstrated significant seasonal dynamics with greater richness and relative abundance of ARGs observed during the dry season compared to the wet season. ARG profiles exhibited a pronounced distance-decay pattern in the dry season, whereas no such pattern was evident in the wet season. Null model analysis indicated that deterministic processes, in contrast to stochastic processes, had a significant impact on shaping the ARG profiles. Furthermore, it was found that Firmicutes and pH emerged as the foremost factors influencing these profiles. This study enhanced our comprehension of the variations in ARG profiles within canal networks, which may contribute to the design of efficient management approaches aimed at restraining the propagation of ARGs.


Assuntos
Rios , Estações do Ano , Rios/microbiologia , Resistência Microbiana a Medicamentos/genética , Hidrologia , Genes Bacterianos , Antibacterianos/farmacologia
13.
Foods ; 13(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38611420

RESUMO

Fruits and vegetables are an important part of our daily diet and contain low-content components that are crucial for our health. Detecting these components accurately is of paramount significance. However, traditional detection methods face challenges such as complex sample processing, slow detection speed, and the need for highly skilled operators. These limitations fail to meet the growing demand for intelligent and rapid detection of low-content components in fruits and vegetables. In recent years, significant progress has been made in intelligent rapid detection technology, particularly in detecting high-content components in fruits and vegetables. However, the accurate detection of low-content components remains a challenge and has gained considerable attention in current research. This review paper aims to explore and analyze several intelligent rapid detection techniques that have been extensively studied for this purpose. These techniques include near-infrared spectroscopy, Raman spectroscopy, laser-induced breakdown spectroscopy, and terahertz spectroscopy, among others. This paper provides detailed reports and analyses of the application of these methods in detecting low-content components. Furthermore, it offers a prospective exploration of their future development in this field. The goal is to contribute to the enhancement and widespread adoption of technology for detecting low-content components in fruits and vegetables. It is expected that this review will serve as a valuable reference for researchers and practitioners in this area.

14.
Dalton Trans ; 53(14): 6399-6409, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498319

RESUMO

A series of Tb3+-doped Sr2YTaO6 double perovskite phosphors (SYT:Tb3+) were synthesized using a conventional solid-state reaction method. A strong green emission was observed in the SYT:Tb3+ phosphors, and the optimal doping concentration of Tb3+ was confirmed to be 5 mol%. The electric dipole-dipole interaction was ascribed to be the main mechanism for the luminescence concentration quenching. Analysis of the concentration-dependent fluorescence decay confirmed that the self-generated quenching model holds for the dynamic process of Tb3+ decays in SYT. Furthermore, the internal quantum efficiencies, non-radiative transition rates, and energy transfer rates of the 5D4 level for the SYT:Tb3+ samples were estimated, respectively. The luminescence thermal stability of the sample was also evaluated based on the Arrhenius model. The chromaticity shift of the SYT:5 mol% Tb3+ phosphor was examined to be 0.013 when the sample temperature was increased from 303 to 483 K, thus indicating excellent chromaticity shifting resistance under high temperature conditions. Moreover, the Judd-Ofelt parameters were calculated from the emission spectra of SYT:Tb3+ to be Ω2 = 0.29 × 10-20, Ω4 = 0.45 × 10-20, and Ω6 = 0.72 × 10-20 cm2, respectively. The fluorescence branching ratios and radiative transition rates for the 5D4 level were calculated based on the obtained Judd-Ofelt parameters. Finally, a white light-emitting diode (LED) prototype was assembled using a 310 nm LED chip combined with a prepared green SYT:Tb3+ phosphor and two other commercial blue and red phosphors. The obtained warm white light exhibits good chromaticity coordinates (0.32, 0.32) and a high color rendering index of 96.1. Based on the above results, it can be known that the prepared SYT:Tb3+ phosphors have a potential application as green emitting phosphors in white LEDs.

15.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123830, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38184878

RESUMO

Anti-counterfeiting labels based on luminescence materials are a newly emerging technique for protecting legal goods and intellectual property. In the anti-counterfeiting field to prevent forgery and cloning, luminescence materials with properties different from the commercialized and traditional ones are in urgent need. In this work, multicolor-emitting Er3+ single-doped and Er3+/Yb3+ co-doped Zn2GeO4 phosphors combining static and dynamic identifications were developed in order to achieve advanced anti-counterfeiting application. The variation of trap content with increasing the doping content of rare earth ions was analyzed through X - ray photoelectron spectroscopy, thermoluminescence analysis. It was found that there are two types of traps with different depth in Zn2GeO4 phosphors. The depths of the traps were experimentally confirmed to be 0.68 and 0.79 eV, respectively. The transient photocurrent response measurement confirmed the existence of charge carriers, and the mechanism for long persistent luminescence was deduced. The multicolor upconversion mechanisms under 980 and 1550 nm excitation were also discovered. Based on the multicolor steady and transient emission features, an anti-counterfeiting pattern was designed using the phosphors. Static and dynamic identification was demonstrated and presented in detail. Finally, it is indicated that the studied phosphors are excellent candidates for potential applications in luminescence anti-counterfeiting labels.

16.
Light Sci Appl ; 13(1): 17, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38225231

RESUMO

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for silicon-based solar cells. In this work, efficient Yb3+ infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er3+ and Yb3+ concentrations, and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er3+/Yb3+ co-doped tungstate system. The quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er3+ to Yb3+. The two-step energy transfer efficiencies, the radiative and nonradiative transition rates of all interested 4 f levels of Er3+ in NaY(WO4)2 were confirmed in the framework of Föster-Dexter theory, Judd-Ofelt theory, and energy gap law, and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173% in NaY(WO4)2: 5 mol% Er3+/50 mol% Yb3+ sample. Strong and nearly pure infrared upconversion emission of Yb3+ under 1550 nm excitation was achieved in Er3+/Yb3+ co-doped NaY(WO4)2 by adjusting Yb3+ doping concentrations. The Yb3+ induced infrared upconversion emission enhancement was attributed to the efficient energy transfer 4I11/2 (Er3+) + 2F7/2 (Yb3+) → 4I15/2 (Er3+) + 2F5/2 (Yb3+) and large nonradiative relaxation rate of 4I9/2. Analysis on the temperature sensing indicated that the NaY(WO4)2:Er3+/Yb3+ serves well the solar cells as thermos-managing material. Moreover, it was confirmed that the fluorescence thermal quenching of 2H11/2/4S3/2 was caused by the nonradiative relaxation of 4S3/2. All the obtained results suggest that NaY(WO4)2:Er3+/Yb3+ is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123683, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38006864

RESUMO

Detecting heavy metal copper ions in lubricating oil holds immense significance for assessing mechanical wear and predicting mechanical failure. While perovskite nanocrystals offer high sensitivity in detecting copper ions, traditional lead halide perovskites suffer from lead toxicity defects. Lead-free perovskites, like Cs2NaInCl6, avoid the issue of lead toxicity but display lower luminescence intensity due to the presence of forbidden optical transitions. To address these issues, this study synthesized Cs2NaInCl6 nanocrystals (NCs) co-doped with Sb3+ and Tb3+ ions for copper ions detection in lubricating oil. The introduction of Sb3+ effectively reduced the band gap of the Cs2NaInCl6 host, creating an energy transfer pathway for Tb3+ emission via self-trapped excitations (STEs). Moreover, the doping of Tb3+ ions resulted in the suppression of STEs emission due to electron transfer from STEs to Tb3+. The emission of Tb3+ increased initially and then decreased with the increasing Tb3+ concentration, peaking at 40 %. Finally, Cs2NaInCl6: 2.5 %Sb3+, 40 %Tb3+ NCs were employed as probes for copper ions detection, exhibiting superior sensitivity and selectivity compared to similar probes. The presence of copper ions introduced competition between copper and Tb3+ for electrons from STEs, consequently leading to the quenching of multiple emission intensities associated with STEs and Tb3+. This method shows promising potential in predicting mechanical failure.

18.
Appl Environ Microbiol ; 89(12): e0146523, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38092675

RESUMO

IMPORTANCE: Microorganisms play important roles in driving the biogeochemical cycles within river ecosystems. It has been suggested that hydrologic conditions could influence microbial communities in rivers, but their specific effects on the behaviours of microbial coalescence have not been thoroughly investigated. In this study, the dynamics of sedimentary bacterial communities within a plain river network were analyzed by amplicon sequencing followed by several ecological models to uncover the underlying assembly processes. Additionally, a comparative analysis between bacterioplankton communities and sedimentary bacterial communities was performed to unveil their coalescence patterns. The results suggested that similar coalescence patterns between sedimentary bacterial and bacterioplankton communities were driven by distinct assembly processes under dynamic hydrological conditions. These findings enhanced our understanding of microbial diversity features within river ecosystems.


Assuntos
Ecossistema , Microbiota , Rios/microbiologia , Organismos Aquáticos , Bactérias/genética , Hidrologia
19.
Nanomaterials (Basel) ; 13(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38132999

RESUMO

Novel and high-security anti-counterfeiting technology has always been the focus of attention and research. This work proposes a nanocomposite combination of upconversion nanoparticles (UCNPs) and perovskite quantum dots (PeQDs) to achieve color-adjustable dual-mode luminescence anti-counterfeiting. Firstly, a series of NaGdF4: Yb/Tm UCNPs with different sizes were synthesized, and their thermal-enhanced upconversion luminescence performances were investigated. The upconversion luminescence (UCL) intensity of the samples increases with rising temperature, and the UCL thermal enhancement factor rises as the particle size decreases. This intriguing thermal enhancement phenomenon can be attributed to the mitigation of surface luminescence quenching. Furthermore, CsPbBr3 PeQDs were well adhered to the surfaces and surroundings of the UCNPs. Leveraging energy transfer and the contrasting temperature responses of UCNPs and PeQDs, this nanocomposite was utilized as a dual-mode thermochromic anti-counterfeiting system. As the temperature increases, the color of the composite changes from green to pink under 980 nm excitation, while it displays green to non-luminescence under 365 nm excitation. This new anti-counterfeiting material, with its high security and convenience, has great potential in anti-counterfeiting applications.

20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(5): 1501-1508, 2023.
Artigo em Chinês | MEDLINE | ID: mdl-37846708

RESUMO

OBJECTIVE: To investigate the clinical features of transplant-associated thrombotic microangiopathy (TA-TMA) and the prognostic value of different prognostic risk models for TA-TMA. METHODS: The clinical characteristics of 32 TA-TMA patients diagnosed at the First Medical Center of the PLA General Hospital from January 2018 to February 2022 in terms of short-term prognosis and influencing factors were retrospectively analyzed. In addition, the risk population composition ratio, treatment response, and overall survival between the BATAP risk model and the TMA index model were compared, as well as the efficacy of two prognostic risk models for predicting death in patients with TA-TMA. RESULTS: Independent risk factors affecting the short-term prognosis of TA-TMA include III-IV aGVHD prior to TA-TMA diagnosis (P=0.001), renal or neurological dysfunction (P=0.006), and Hb<70 g/L (P=0.043). In the TMA index model, treatment response was worst in the high-risk group (P=0.008), while there was no significant difference in treatment response between different risk groups in the BATAP model (P=0.105). In the BATAP model, there was a statistically significant difference in the OS between the three groups of low risk, intermediate risk, and high risk (87.5% vs 61.1% vs 16.7%, χ2=6.7, P=0.014). In the TMA index model, there was a statistically significant difference in the OS between the three groups of low risk, intermediate risk, and high risk (77.8% vs 45.5% vs 0.0%, χ2=7.3, P=0.017). The area under the ROC curve (AUC) of the TMA index model was 0.745 (95%CI: 0.56-0.88, P<0.05), and the AUC of the BATAP model was 0.743 (95%CI: 0.56-0.88, P<0.05), indicating that both prognostic risk models have good predictive value. CONCLUSION: The short-term prognosis of TA-TMA patients might be accurately determined using both the BATAP model and the TMA index model. When predicting the efficacy of TA-TMA in different risk groups, the TMA index model may perform better than the BATAP model.

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