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1.
Small ; 20(23): e2309134, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38150666

RESUMEN

Almost all colloidal quantum dots (QDs) exhibit undesired photoluminescence (PL) blinking, which poses a significant obstacle to their use in numerous luminescence applications. An in-depth study of the blinking behavior, along with the associated mechanisms, can provide critical opportunities for fabricating high-quality QDs for diverse applications. Here the blinking of a large series of colloidal QDs is investigated with different surface ligands, particle sizes, shell thicknesses, and compositions. It is found that the blinking behavior of single alloyed CdSe/ZnS QDs with a shell thickness of up to 2 nm undergoes an irreversible conversion from Auger-blinking to band-edge carrier blinking (BC-blinking). Contrastingly, single perovskite QDs with particle sizes smaller than their Bohr diameters exhibit reversible conversion between BC-blinking and more pronounced Auger-blinking. Changes in the effective trapping sites under different excitation conditions are found to be responsible for the blinking type conversions. Additionally, changes in shell thickness and particle size of QDs have a significant effect on the blinking type conversions due to altered wavefunction overlap between excitons and effective trapping sites. This study elucidates the discrepancies in the blinking behavior of various QD samples observed in previous reports and provides deeper understanding of the mechanisms underlying diverse types of blinking.

2.
Opt Express ; 32(4): 6025-6036, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439315

RESUMEN

Quantum imaging based on entangled light sources exhibits enhanced background resistance compared to conventional imaging techniques in low-light conditions. However, direct imaging of dynamic targets remains challenging due to the limited count rate of entangled photons. In this paper, we propose a quantum imaging method based on quantum compressed sensing that leverages the strong correlation characteristics of entangled photons and the randomness inherent in photon pair generation and detection. This approach enables the construction of a compressed sensing system capable of directly imaging high-speed dynamic targets. The results demonstrate that our system successfully achieves imaging of a target rotating at a frequency of 10 kHz, while maintaining an impressive data compression rate of 10-6. This proposed method introduces a pioneering approach for the practical implementation of quantum imaging in real-world scenarios.

3.
Opt Express ; 32(6): 10419-10428, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571254

RESUMEN

Twisted stacking of two-dimensional materials with broken inversion symmetry, such as spiral MoTe2 nanopyramids and supertwisted spiral WS2, emerge extremely strong second- and third-harmonic generation. Unlike well-studied nonlinear optical effects in these newly synthesized layered materials, photoluminescence (PL) spectra and exciton information involving their optoelectronic applications remain unknown. Here, we report layer- and power-dependent PL spectra of the supertwisted spiral WS2. The anomalous layer-dependent PL evolutions that PL intensity almost linearly increases with the rise of layer thickness have been determined. Furthermore, from the power-dependent spectra, we find the power exponents of the supertwisted spiral WS2 are smaller than 1, while those of the conventional multilayer WS2 are bigger than 1. These two abnormal phenomena indicate the enlarged interlayer spacing and the decoupling interlayer interaction in the supertwisted spiral WS2. These observations provide insight into PL features in the supertwisted spiral materials and may pave the way for further optoelectronic devices based on the twisted stacking materials.

4.
J Chem Phys ; 160(17)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38748025

RESUMEN

Determining the correlation between the size of a single quantum dot (QD) and its photoluminescence (PL) properties is a challenging task. In the study, we determine the size of each QD by measuring its absorption cross section, which allows for accurate investigation of size-dependent PL blinking mechanisms and volume scaling of the biexciton Auger recombination at the single-particle level. A significant correlation between the blinking mechanism and QD size is observed under low excitation conditions. When the QD size is smaller than their Bohr diameter, single CsPbI3 perovskite QDs tend to exhibit BC-blinking, whereas they tend to exhibit Auger-blinking when the QD size exceeds their Bohr diameter. In addition, by extracting bright-state photons from the PL intensity trajectories, the effects of QD charging and surface defects on the biexcitons are effectively reduced. This allows for a more accurate measurement of the volume scaling of biexciton Auger recombination in weakly confined CsPbI3 perovskite QDs at the single-dot level, revealing a superlinear volume scaling (τXX,Auger ∝ σ1.96).

5.
BMC Pulm Med ; 24(1): 65, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38297272

RESUMEN

BACKGROUND: Exercise is crucial for pulmonary rehabilitation and improving the prognosis of lung transplantation (LTx) patients. However, many LTx patients in China have low exercise tolerance and compliance, and the reasons behind these challenges have not been fully elucidated. Therefore, this qualitative research aims to identify the barriers to and facilitators of exercise rehabilitation in LTx patients. METHODS: From January to July 2023, 15 stable LTx patients were recruited and participated in in-depth, semi-structured, face-to-face interviews at Henan Provincial People's Hospital. The interview transcripts were analyzed using the COM-B model and the Theoretical Domains Framework (TDF). RESULTS: Six general themes including 19 barriers and 14 facilitators for the exercise rehabilitation of LTx patients were identified based on the COM-B model and TDF. The barriers to exercise included physical limitations, insufficient exercise endurance, lack of knowledge, and lack of motivation. The facilitators of exercise included motivation, self-efficacy, perceived significance of exercise rehabilitation, and social support. CONCLUSION: The study offers detailed insight into the development and implementation of exercise rehabilitation intervention strategies for LTx patients. By combining COM-B model and TDF, the study provides strong evidence that active behavior change strategies are required for LTx patients to promote their participation in exercise rehabilitation. Professional support, pulmonary rehabilitation training, behavior change technology, and digital health tools are essential for strengthening the evidence system for reporting exercise efficacy and effectiveness.


Asunto(s)
Ejercicio Físico , Trasplante de Pulmón , Adulto , Humanos , Investigación Cualitativa , Terapia por Ejercicio , Apoyo Social , Motivación
6.
Anal Chem ; 95(26): 9959-9966, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37351568

RESUMEN

Being characterized by the self-adaption and high accuracy, the deep learning-based models have been widely applied in the 1D spectroscopy-related field. However, the "black-box" operation and "end-to-end" working style of the deep learning normally bring the low interpretability, where a reliable visualization is highly demanded. Although there are some well-developed visualization methods, such as Class Activation Mapping (CAM) and Gradient-weighted Class Activation Mapping (Grad-CAM), for the 2D image data, they cannot correctly reflect the weights of the model when being applied to the 1D spectral data, where the importance of position information is not considered. Here, aiming at the visualization of Convolutional Neural Network-based models toward the qualitative and quantitative analysis of 1D spectroscopy, we developed a novel visualization algorithm (1D Grad-CAM) to more accurately display the decision-making process of the CNN-based models. Different from the classical Grad-CAM, with the removal of the gradient averaging (GAP) and the ReLU operations, a significantly improved correlation between the gradient and the spectral location and a more comprehensive spectral feature capture were realized for 1D Grad-CAM. Furthermore, the introduction of difference (purity or linearity) and feature contribute in the CNN output in 1D Grad-CAM achieved a reliable evaluation of the qualitative accuracy and quantitative precision of CNN-based models. Facing the qualitative and adulteration quantitative analysis of vegetable oils by the combination of Raman spectroscopy and ResNet, the visualization by 1D Grad-CAM well reflected the origin of the high accuracy and precision brought by ResNet. In general, 1D Grad-CAM provides a clear vision about the judgment criterion of CNN and paves the way for CNN to a broad application in the field of 1D spectroscopy.

7.
Opt Express ; 31(5): 7564-7571, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859885

RESUMEN

Infrared up-conversion single-photon imaging has potential applications in remote sensing, biological imaging, and night vision imaging. However, the used photon counting technology has the problem of long integration time and sensitivity to background photons, which limit its application in real-world scenarios. In this paper, a novel passive up-conversion single-photon imaging method is proposed, in which the high frequency scintillation information of a near infrared target is captured by using the quantum compressed sensing. Through the frequency domain characteristic imaging of the infrared target, the imaging signal-to-noise ratio is significantly improved with strong background noise. In the experiment, the target with flicker frequency on the order of GHz is measured, and the signal-to-background ratio of the imaging reaches up to 1:100. Our proposal greatly improved the robustness of near-infrared up-conversion single-photon imaging and will promote its practical application.

8.
Cell Mol Biol (Noisy-le-grand) ; 69(13): 270-278, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38158666

RESUMEN

Long non-coding RNAs (lncRNAs) have a vital potential in premature delivery. This research was intended to explore PSMA3-AS1's role in premature delivery as well as its possible molecular mechanism. We enrolled 100 premature delivery patients and 100 term patients. Fetal membranes were collected. RT-qPCR was adopted for evaluating PSMA3-AS1, miRNA-224-3p, along with Nrf2 expression. Cell function experiments were implemented to clarify PSMA3-AS1 functions in human trophoblast HTR-8/SVneo cells. Rescue together with mechanistic experiments were implemented for assessing the regulatory function and interaction between miR-224-3p and PSMA3-AS1 or Nrf2 axis in human trophoblast cells. The results uncovered that PSMA3-AS1 level presented downregulation in the fetal membrane tissues and human trophoblast cells. Overexpressed PSMA3-AS1 enhanced cell proliferation but suppressed ferroptosis in human trophoblast cells. Besides, PSMA3-AS1 elevation also attenuated the LPS-induced inflammatory response and restored the LPS-induced upregulation of 20α-HSD and downregulation of progesterone (P4). Mechanistically, miR-224-3p could bind to PSMA3-AS1 and present upregulation in fetal membranes and human trophoblast cells. Notably, overexpressed miR-224-3p offset the influences of PSMA3-AS1 on human trophoblast cell proliferation and ferroptosis. Furthermore, Nrf2 was targeted by miR-224-3p. Downregulated Nrf2 offset the influences of the miR-224-3p inhibitor and induced HTR-8/SVneo dysfunction. Additionally, Nrf2 transcriptionally activated PSMA3-AS1 and GPX4. In conclusion, PSMA3-AS1 expression is low during premature delivery and overexpressing PSMA3-AS1 promotes proliferation and suppresses ferroptosis of human trophoblast cells by interacting with miR-224-3p to downregulate Nrf2. Therefore, enhancing PSMA3-AS1 expression may be a promising therapeutic strategy to prevent premature delivery.


Asunto(s)
Ferroptosis , MicroARNs , Nacimiento Prematuro , ARN Largo no Codificante , Femenino , Humanos , Recién Nacido , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Lipopolisacáridos , MicroARNs/genética , MicroARNs/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Nacimiento Prematuro/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Embarazo
9.
Opt Express ; 30(15): 26557-26569, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-36236844

RESUMEN

The optical interference effect originating from the multiple reflections between the two-dimensional (2D) materials and the substrates has been used to dramatically enhance their Raman signal. However, this effect in the hybrid structures of colloidal quantum dots (QD) coupled to 2D materials is always overlooked. Here we theoretically prove that the photoluminescence (PL) intensities of the QD films in the QD-2D hybrid structures can be strongly enhanced and modulated by the optical interference effect between QD and 2D interfaces, breaking the inherent standpoint that PL intensities of the QD films are always prominently quenched in these hybrid structures. The theoretical predictions have been well confirmed by experimental measurements of PL properties of CdSe/ZnS and CdSeTe/ZnS QD on different 2D materials (such as WSe2, MoS2, and h-BN). PL intensities of these QD films have been periodically modulated from almost disappearing to strong enhancement (with the enhancement of about 6 times). The optical interference effect uncovered in this work enables a powerful method to manipulate the PL property of the QD films in the different QD-2D hybrid structures. These results can boost the optical performance of the QD-based electronic and optoelectronic devices in the hybrid QD-2D structures.

10.
Nano Lett ; 21(3): 1477-1483, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33507086

RESUMEN

Massive magical phenomena in nature are closely related to quantum effects at the microscopic scale. However, the lack of straightforward methods to observe the quantum coherent dynamics in integrated biological systems limits the study of essential biological mechanisms. In this work, we developed a single-molecule coherent modulation (SMCM) microscopy by combining the superior features of single-molecule microscopy with ultrafast spectroscopy. By introducing the modem technology and defining the coherent visibility, we realized visualization and real-time observation of the decoherence process of a single molecule influenced by the microenvironment for the first time. In particular, we applied this technique to observe the quantum coherent properties of the entire chlorella cells and found the correlation between the coherent visibility and metabolic activities, which may have potential applications in molecular diagnostics and precision medicine.


Asunto(s)
Chlorella , Imagen Individual de Molécula , Microscopía , Nanotecnología , Análisis Espectral
11.
Opt Express ; 29(2): 1851-1869, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726390

RESUMEN

Photostability has always been an important issue that limits the performance of organo-metal halide perovskites in optoelectronic devices. Although the photostability can be partially improved by polymer coating/encapsulation, one rising question that needs to be considered is whether the improvement of photostability is accessed at the expense of intangible loss in photoluminescence (PL) properties. By in situ analyzing the evolution of PL properties of individual perovskite crystals during the polymer encapsulation procedure, we demonstrate here that poly(methyl methacrylate), a common polymeric encapsulant, would passivate the surface defects of perovskite crystals, leading to the suppress of PL blinking. However, somewhat counterintuitive, the toluene solvent will induce the PL decline of individual perovskite crystals via accumulation of the number of quenchers that, most probably, are related to the ion migration in perovskite. The findings at the single-particle level emphasize the often-neglected role of the polymer matrix and the solvent in the optical properties of perovskite material during the polymer encapsulation process, and will guide the further design of more stable and high-performance devices based on perovskite.

12.
Opt Express ; 29(6): 8880-8889, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33820329

RESUMEN

GaTe nanoflakes have been receiving much research attention recently due to their applications in optoelectronic devices, such as anisotropic non-volatile memory, solar cells, and high-sensitivity photodetectors from the ultraviolet to the visible region. Further applications, however, have been impeded due to the limited understanding of their exciton dynamics. In this work we perform temperature- and power-dependent time-resolved photoluminescence (PL) spectra to comprehensively investigate the exciton dynamics of GaTe nanoflakes. Temperature-dependent PL measurements manifest that spectral profiles of GaTe nanoflakes change dramatically from cryogenic to room temperature, where the bound exciton and donor-to-acceptor pair transition normally disappear above 100 K, while the charged exciton survives to room temperature. The lifetimes of these excitons and their evolution vs temperature have been uncovered by time-resolved PL spectra. Further measurements reveal the entirely different power-dependent exciton behaviors of GaTe nanoflakes between room and cryogenic temperatures. The underlying mechanisms have been proposed to explore the sophisticated exciton dynamics within GaTe nanoflakes. Our results offer a more thorough understanding of the exciton dynamics of GaTe nanoflakes, enabling further progress in engineering GaTe-based applications, such as photodetectors, light-emitting diodes, and nanoelectronics.

13.
Opt Express ; 29(15): 22855-22867, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34614564

RESUMEN

Au nanoparticles are attractive contrast agents for noninvasive living tissue imaging with deep penetration because of their strong two-photon photoluminescence (TPPL) intensity and excellent biocompatibility. However, the inevitable phototoxicity and huge auto-fluorescence are consistently associated with laser excitation. Therefore, enhancement of TPPL intensity and suppression of backgrounds are always highly desired under the demand of reducing excitation powers. In this work, we develop a double-pulse TPPL (DP-TPPL) scheme with controlled phase differences (Δφ) between the double pulses to significantly improve the signal-to-noise ratio (SNR) of TPPL imaging. Under the modulated phase (Δφ periodically varying between 0-2π), our results show that SNR can be improved from 4.3 to 1715, with an enhancement of up to 400 folds at the integration of 50 ms. More importantly, this enhancement can be unlimitedly lifted by increasing the number of photons or integration times in principle. Further boosting has been achieved by reducing the magnitude of background noises; subsequently, SNR is improved by more than 104 times. Our schemes offer great potential for reducing phototoxicity and extracting extremely weak signals from huge backgrounds and open up a new possibility for a rapid, flexible, and reliable medical diagnosis by TPPL imaging with diminished laser powers.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Sondas Moleculares/química , Imagen Individual de Molécula/métodos , Fluorescencia , Rayos Láser
14.
Phys Rev Lett ; 127(7): 073902, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34459625

RESUMEN

The interaction between light and metal nanoparticles enables investigations of microscopic phenomena on nanometer length and ultrashort timescales, benefiting from strong confinement and enhancement of the optical field. However, the ultrafast dynamics of these nanoparticles are primarily investigated by multiphoton photoluminescence on picoseconds or photoemission on femtoseconds independently. Here, we presented two-photon photoluminescence (TPPL) measurements on individual Au nanobipyramids (AuNP) to reveal their ultrafast dynamics by double-pulse excitation on a global timescale ranging from subfemtosecond to tens of picoseconds. Two orders of magnitude photoluminescence enhancement, namely, coherent interference fringes, has been demonstrated. Power-dependent measurements uncovered the transform of the nonlinearity from 1 to 2 when the interpulse delay varied from tens of femtoseconds to tens of picoseconds. We proved that the real intermediate state plays a critical role in the observed phenomena, supported by numerical simulations with a three-state model. Our results provide insight into the role of intermediate states in the ultrafast dynamics of noble metal nanoparticles. The presence of the intermediate states in AuNP and the coherent control of state populations offer interesting perspectives for imaging, sensing, nanophotonics, and in particular, for preparing macroscopic superposition states at room temperature and low-power superresolution stimulated emission depletion microscopy.

15.
Eur Radiol ; 31(5): 3187-3194, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33052467

RESUMEN

OBJECTIVES: To investigate age-related changes on passive muscle stiffness in healthy individuals and measure the shear modulus in different age groups. METHODS: Shear wave elastography (SWE) movies of gastrocnemius medialis (GM) were collected during passive stretching induced by ankle rotation from plantarflexion (PF) to dorsiflexion (DF). A series of SWE images at ankle angles of PF 40°, PF 30°, PF 20°, PF 10°, 0°, DF 10°, DF 20°, and DF 30° were collected and shear moduli measured accordingly for analyses. RESULTS: Eighty-six healthy volunteers (27 children, 31 middle-aged adults, and 28 older people) were recruited. No significant difference was observed in the shear modulus between the three groups at ankle angles of PF 40°, PF 30°, PF 20°, PF 10°, and 0° (p > 0.05). The difference in the shear modulus among the three groups became significant as DF increased. At ankle angles of DF 10°, DF 20°, and DF 30°, the shear modulus was the greatest in the older group, followed by the middle-aged group and then the children group (p = 0.007, 0.000, and 0.000, respectively). CONCLUSIONS: Passive muscle stiffness increases with age, and the difference between age groups was pronounced only after reaching a certain degree of stretching. KEY POINTS: • The influence of age on passive muscle stiffness becomes pronounced only after reaching a certain degree of stretching. • Age should be considered when evaluating passive muscle stiffness in muscular disorders.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Adulto , Anciano , Anciano de 80 o más Años , Tobillo , Articulación del Tobillo/diagnóstico por imagen , Niño , Humanos , Persona de Mediana Edad , Músculo Esquelético/diagnóstico por imagen , Rango del Movimiento Articular
16.
J Chem Phys ; 155(24): 244301, 2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34972379

RESUMEN

Photoblinking and photobleaching are commonly encountered problems for single-photon sources. Numerous methods have been devised to suppress these two impediments; however, either the preparation procedures or the operating conditions are relatively harsh, making them difficult to apply to practical applications. Here, we reported giant suppression of both photoblinking and photobleaching of a single fluorescent molecule, terrylene, via the utilization of hexagonal boron nitride (h-BN) flakes as substrates. Experimentally, a much-prolonged survival time of terrylene has been determined, which can have a photostable emission over 2 h at room temperature under ambient atmospheres. Compared with single molecules on a SiO2/Si substrate or glass coverslip, a more than 100-fold increase in the total number of photons collected from each terrylene on h-BN flakes has been demonstrated. We also proved that the photostability of terrylene molecules can be well maintained for more than 6 months even under ambient conditions without any further protection. Our results demonstrate that the utilization of h-BN flakes to suppress photoblinking and photobleaching of fluorescent molecules has promising applications in the production of high-quality single-photon sources at room temperature.

17.
J Obstet Gynaecol ; 41(1): 73-76, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32420780

RESUMEN

The exact prevalence of mirror syndrome remains unclear, and the precise clinical features need to be disclosed. We retrospectively reviewed 85 cases of foetal hydrops from a total of 98,484 deliveries. Of these 16 showed mirror syndrome, while 69 did not. The incidence of mirror syndrome among all deliveries was 0.0162%, while that among patients with foetal hydrops was 23.2%. Maternal symptoms of mirror syndrome included anaemia (n = 15), hypertension (n = 7), proteinuria (n = 8), pulmonary oedema (n = 3), cardiac failure (n = 2) and HELLP syndrome (n = 2). Placental thickness, placental weight and amniotic fluid index were significantly different between the groups. In the mirror syndrome group, uric acid, lactate dehydrogenase, creatinine and D-dimer levels were significantly higher (p < .05), whereas haemoglobin, serum albumin levels, haematocrit value and platelet count were significantly lower (p < .05). Elevated uric acid, lactate dehydrogenase and D-dimer levels may be useful as predictors of mirror syndrome.Impact statementWhat is already known on this subject? As mirror syndrome is uncommon and under-diagnosed, its exact incidence is not yet clear, and most publications are case reports or reviews of case reports.What the results of this study add? The incidence of mirror syndrome among all deliveries was 0.0162%, while that among patients with foetal hydrops was 23.2%. Pregnant women who develop mirror syndrome may show severe complications of pregnancy. Attention should be paid to the further progress of the condition. Placental thickness, placental weight and amniotic fluid index were significantly different between those with mirror syndrome and those without. In the mirror syndrome group, the uric acid, lactate dehydrogenase, creatinine and D-dimer levels were significantly higher (p < .05), whereas haemoglobin level, haematocrit value, platelet count and serum albumin level were significantly lower (p < .05).What the implications are of these findings for clinical practice and/or further research? Mirror syndrome is not rare among patients with foetal hydrops. Elevated uric acid, lactate dehydrogenase and D-dimer levels may be useful as predictors of mirror syndrome.


Asunto(s)
Edema/patología , Hidropesía Fetal/patología , Complicaciones del Embarazo/patología , Adulto , Edema/sangre , Edema/complicaciones , Femenino , Humanos , Placenta/patología , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/etiología , Estudios Retrospectivos , Síndrome
18.
Small ; 16(51): e2005435, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33236844

RESUMEN

Lead halide perovskite quantum dots (QDs) are promising materials for next-generation photoelectric devices because of their low preparation costs and excellent optoelectronic properties. In this study, the blinking mechanisms and the intrinsic quantum-confined Stark effect (IQCSE) in single organic-inorganic hybrid CH3 NH3 PbBr3 perovskite QDs using single-dot photoluminescence (PL) spectroscopy is investigated. The PL quantum yield-recombination rates distribution map allows the identification of different PL blinking mechanisms and their respective contributions to the PL emission behavior. A strong correlation between the excitation power and the blinking mechanisms is reported. Most single QDs exhibit band-edge carrier blinking under a low excitation photon fluence. While under a high excitation photon fluence, different proportions of Auger-blinking emerge in their PL intensity trajectories. In particular, significant IQCSEs in the QDs that exhibit more pronounced Auger-blinking are observed. Based on these findings, an Auger-induced IQCSE model to explain the observed IQCSE phenomena is observed.

19.
Int J Mol Sci ; 21(11)2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32527042

RESUMEN

This study investigated the prognostic effects of genomic biomarkers for predicting chemoradiotherapy (CRT)-based treatment outcomes in patients with adenocarcinoma (AC) of the uterine cervix. In all, 21 patients receiving definitive CRT were included. In accordance with the International Federation of Gynecology and Obstetrics (FIGO) staging system, 5, 8, and 8 patients were classified as having stage IB3, II, and III disease, respectively. Pretreatment biomarkers were analyzed using tissue microarrays from biopsy specimens. Genomic alterations were examined by next-generation sequencing (NGS). The outcome endpoints were disease-free survival (DFS), distant metastasis-free survival (DMFS), and local relapse-free survival (LRFS). A Cox regression model was used to examine the prognostic effects of the biomarkers and clinical parameters. The presence of myeloid cell leukemia-1 (MCL1) gene amplification and a lower immunohistochemical (IHC) marker of tumor necrotic factor alpha (TNF-α) H-score were two prognostic factors for inferior DFS. The four-year DFS was 28% and 68% for patients with or without MCL1 copy number gain, respectively (p = 0.028). In addition, MCL1 amplification predicted poor DMFS. A lower tumor mutation number (TMN) calculated from nonsynonymous mutations was associated with lower LRFS. For patients with adenocarcinoma of the uterine cervix receiving definitive CRT, prognostic information can be supplemented by MCL1 amplification, the TMN, and the TNF-α H score.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Biomarcadores de Tumor/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Quimioradioterapia , Supervivencia sin Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Pronóstico , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/mortalidad
20.
Opt Express ; 27(3): 2886-2898, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732319

RESUMEN

Photoluminescence (PL) of Au nanoparticles is appealing for various biological applications, owing to their unique advantages. However, widespread applications are still limited by their extremely low quantum yield. Here, we report on the giant PL enhancement of aggregated Au nanospheres by continuous-wave (CW) laser irradiation. Our studies show that the laser-induced PL enhancement is influenced by the wavelength and power density of irradiation laser, as well as the size of Au nanospheres. The averaged intensity of Au nanospheres after irradiation by 405 nm CW laser at power density of 6 MW/cm2 is 75 times that of the as-prepared sample, where the highest enhancement of 150 folds is obtained. The giant PL enhancement is attributed to laser-induced photothermal welding and reshaping of adjacent Au nanospheres, which will dramatically enhance the incidence light field in the crevices around the welding areas by surface plasmon resonance. These studies not only declare that Au nanospheres are expected to find many new applications in PL-based biosensing and bioiamging, but also suggest that CW laser can be used as a versatile tool to weld and reshape the Au nanospheres in order to build up functionalized electronic and optoelectronic devices.

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