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1.
Int J Hyperthermia ; 40(1): 2172219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36775652

RESUMO

OBJECTIVES: Current predictors are largely unsatisfied for early recurrence (ER) of hepatocellular carcinoma (HCC) after thermal ablation. We aimed to explore the prognostic value of peripheral immune factors (PIFs) for better ER prediction of HCC after thermal ablation. METHODS: Patients who received peripheral blood mononuclear cells (PBMCs) tests before thermal ablation were included. Clinical parameters and 18 PIFs were selected to construct ModelClin, ModelPIFs and the hybrid ModelPIFs-Clin. Model performances were evaluated using area under the curve (AUC), and recurrence-free survival (RFS) were analyzed by Kaplan-Meier analysis and log-rank tests. RESULTS: 244 patients were included and were randomly divided in 3:1 ratio to discovery and validation cohorts. Clinical parameters including tumor size and AFP, and PIFs including neutrophils, platelets, CD3+CD16+CD56+ NKT and CD8+CD28- T lymphocytes were selected. The ModelPIFs-Clin showed increase in predictive performance compared with ModelClin, with the AUC improved from 0.664 (95%CI:0.588-0.740) to 0.801 (95%CI:0.734-0.867) in discovery cohort (p < 0.0001), and from 0.645 (95%CI:0.510-0.781) to 0.737(95%CI:0.608-0.865) in validation cohort (p = 0.1006). ModelPIFs-Clin enabled ER risk stratification of patients. Patients predicted in ModelPIFs-Clin high-risk subgroup had a poor RFS compared with those predicted as ModelPIFs-Clin low-risk subgroup, with the median RFS was 18.00 month versus 100.78 month in discovery cohort (p < 0.0001); and 24.00 month versus 60.35 month in validation cohort (p = 0.288). Patients in different risk subgroups exhibited distinct peripheral immune contexture. CONCLUSIONS: Peripheral immune cells aiding clinical parameters boosted the prediction ability for ER of HCC after thermal ablation, which be helpful for pre-ablation ER risk stratification.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Leucócitos Mononucleares , Prognóstico , Hepatectomia , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
2.
Opt Express ; 30(17): 30870-30880, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242183

RESUMO

Fiber lasers, owing to the advantages of excellent beam quality and unique robustness, play a crucial role in lots of fields in modern society. Developing optical glass fibers with superior performance is of fundamental importance for wide applications of fiber lasers. Here, a new Nd3+-doped phosphate single-mode fiber that enables a high gain at 0.9 µm is designed and fabricated. Compared to previous Nd3+-doped silica fibers, the developed phosphate fiber exhibits a significant gain promotion, up to 2.7 dB cm-1 at 915 nm. Configuring in a continuous-wave fiber laser, this phosphate fiber can provide a slope efficiency of 11.2% in a length of only 4.5 cm, about 6 times higher than that of Nd3+-doped silica fiber. To showcase its uniqueness, an ultrafast fiber laser with ultrashort cavity is constructed, such that an ultrashort pulse train with a fundamental repetition rate of up to 1.2 GHz is successfully generated. To the best of our knowledge, this is the highest fundamental repetition rate for mode-locked fiber lasers at this wavelength range - two orders of magnitude higher than that of prior works. These results indicate that this Nd3+-doped phosphate fiber is an effective gain medium for fiber amplifiers and lasers at 0.9 µm, and it is promising for two-photon biophotonics that requires long-term operation with low phototoxicity.

3.
PLoS Genet ; 15(1): e1007408, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30608921

RESUMO

The mechanisms that ensure fertilization of egg by a sperm are not fully understood. In all teleosts, a channel called the 'micropyle' is the only route of entry for sperm to enter and fertilize the egg. The micropyle forms by penetration of the vitelline envelope by a single specialized follicle cell, the micropylar cell. The mechanisms underlying micropylar cell specification and micropyle formation are poorly understood. Here, we show that an effector of the Hippo signaling pathway, the Transcriptional co-activator with a PDZ-binding domain (Taz), plays crucial roles in micropyle formation and fertilization in zebrafish (Danio rerio). Genome editing mutants affecting taz can grow to adults. However, eggs from homozygous taz females are not fertilized even though oocytes in mutant females are histologically normal with intact animal-vegetal polarity, complete meiosis and proper ovulation. We find that taz mutant eggs have no micropyle. Taz protein is specifically enriched in mid-oogenesis in the micropylar cell located at the animal pole of wild type oocyte, where it might regulate the cytoskeleton. Taz protein and micropylar cells are not detected in taz mutant ovaries. Our work identifies a novel role for the Hippo/Taz pathway in micropylar cell specification in zebrafish, and uncovers the molecular basis of micropyle formation in teleosts.


Assuntos
Desenvolvimento Embrionário/genética , Fertilização/genética , Oogênese/genética , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Aciltransferases , Animais , Animais Geneticamente Modificados , Citoesqueleto/genética , Citoesqueleto/ultraestrutura , Embrião não Mamífero , Feminino , Masculino , Oócitos/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , Ovário/ultraestrutura , Proteínas Serina-Treonina Quinases/genética , Serina-Treonina Quinase 3 , Transdução de Sinais , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/ultraestrutura , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
4.
Ecotoxicol Environ Saf ; 243: 113974, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988381

RESUMO

In recent years, cardiovascular diseases (CVDs) have become the primary cause of death in the world. Existing studies have found that greenspace is important for the prevention of CVDs and stroke. However, since they only focus on large green infrastructure (e.g., urban parks) or the general greenspace (usually being evaluated through normalized difference vegetation index), little information exists regarding the association between street-level greenspace and CVDs (stroke). In this study, the CVDs and stroke data of participants were retrieved from the 33 Chinese Community Health Study. We measured participants' exposure to street-level greenspace exposure using street view images and machine learning technique. Multilevel logistic regressions were applied. While controlling for confounders, we found that higher level of street-level greenspace exposure was associated with lower CVDs prevalence. However, street-level greenspace exposure was associated with stroke prevalence only for females. The associations were stronger among females, younger adults, participants with educational attainment above high school, physically active participants and participants who were not overweight. None of the mediators (air pollution, physical exercise, and BMI) can explain the associations between street-level greenspace exposure and CVDs (stroke) prevalence. Our findings suggest that street-level vegetation should be increased to cope with the rapid growth of the CVDs burdens. Also, the differences between the effect of street-level trees and grasses should be noted before formulating specific urban planning policies.


Assuntos
Poluição do Ar , Doenças Cardiovasculares , Acidente Vascular Cerebral , Adulto , Doenças Cardiovasculares/epidemiologia , China/epidemiologia , Feminino , Humanos , Parques Recreativos , Acidente Vascular Cerebral/epidemiologia
5.
Genesis ; 58(2): e23345, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31705616

RESUMO

Myosin phosphatase targeting subunit 1 (Mypt1) is the regulatory subunit of myosin phosphatase which dephosphorylates the light chain of myosin II to inhibit its contraction. Although biochemical properties of Mypt1 have been characterized in detail, its biological functions in organisms are not well understood. The zebrafish mypt1 sq181 allele was found defective in the ventral pancreatic bud and extrapancreatic duct development, resulting in dysplasia of exocrine pancreas. In mypt1 sq181 mutant, the early growth of the ventral pancreatic bud was initiated but failed to expand due to impaired cell proliferation and increased cell apoptosis. As Mypt1 is essential for cell migration, the loss-of-function of Mypt1 in the mutant disrupted the lateral plate mesoderm migration during gut looping, therefore, altering the Bmp2a expression pattern within it, and eventually leading to impaired Bmp signaling in the adjacent exocrine pancreas. Overexpression of bmp2a could rescue the development of exocrine pancreas, suggesting that the impaired Bmp2a signaling is responsible for the pancreatic development defects. Bmp2a has been reported to promote the early specification of the ventral pancreatic bud, and our study reveals that it continues to serve as a cell proliferation/survival signal to ensure pancreatic bud growth properly in zebrafish.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Pâncreas Exócrino/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Apoptose , Proteína Morfogenética Óssea 2/genética , Regulação da Expressão Gênica no Desenvolvimento , Mutação com Perda de Função , Fosfatase de Miosina-de-Cadeia-Leve/genética , Pâncreas Exócrino/embriologia , Transdução de Sinais , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
6.
Small ; 15(43): e1904298, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31490613

RESUMO

Precise knowledge about optical and structural performance of individual rare earth (RE)-doped particles is extremely important for the optimization of luminescent particles and for fully exploiting their capability as multifunctional probes for interdisciplinary applications. In this work, optical and structural anisotropy of individual particles through RE-doped single fluoride microcrystals with controllable morphology is reported. Unique luminescent phenomena, for example, white light-emission from Pr3+ at single particle level and different photoluminescent spectra variation dependence on excitation polarization orientation at different excitation direction are observed upon excitation with a 980 nm linearly polarized laser. Based on the analysis of local site symmetry and electron cloud distribution of REs in hexagonal structure by density functional theory calculations, an exciting mechanism of excitation polarization response anisotropy is given for the first time, providing a guidance for emission polarization simultaneously. The structural anisotropy is presented in Raman spectra with obvious differing Raman curves, revealing the reason why there are differences between powder groups. Taking advantage of anisotropic crystals, potential applications in microscopic multi-information transportation are suggested for the optical and structural performance anisotropy from RE-doped fluoride single nano/microcrystals to ordered nano/microcrystal arrays, such as local rate probing in a flowing liquid.

7.
Opt Express ; 25(17): 19691-19700, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-29041657

RESUMO

All solid-state PbS quantum dot (QD)-doped glass precursor fibers avoiding crystallization during fiber-drawing process are successfully fabricated by melt-in-tube technique. By subsequent heat treatment schedule, controllable crystallization of PbS QDs can be obtained in the glass precursor fibers, contributing to broad near-infrared emissions from PbS QD-doped glass fibers. Nevertheless, we find that element-migration and volatilization of sulfur simultaneously happen during the whole fiber-drawing process, because of the huge difference between the melting temperature of core glass and the fiber-drawing temperature. Element-migration pathways along the fiber length were revealed. Such PbS QD-doped glass fiber with broadband emissions will be a potential application as gain medium of broadband fiber amplifiers and fiber lasers.

8.
Opt Express ; 23(2): 1370-6, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25835895

RESUMO

We investigated the influence of laser-induced air breakdown on the femtosecond laser ablation of aluminum target using time-resolved pump-probe shadowgraphic imaging method. The early-stage plasma expanding dynamics and subsequent expanding behaviors of shockwaves and material ejection plume were analyzed through shadowgraphs recorded at different time delays. The dominated mechanisms were clarified at different stages during femtosecond laser pulses ablating aluminum, which provide very valuable information for ultrashort laser ablation of metals.

9.
Opt Express ; 23(13): 16723-9, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191684

RESUMO

PbS quantum dot (QD)-doped glass was prepared by the heat treatment of as-prepared glass, which was confirmed by transmission electron microscope (TEM), absorption and photoluminescence (PL) spectra. Choosing the glass heat treatment at 600°C for 24h as a representative sample, steady-state and transient-state PL, lifetime and time-resolve emission spectra (TRES) of PbS QD-doped glass were studied in detail. The results indicated that the lifetime spectra showed a similar variation tendency with the PL spectra. The steady-state, transient-state PL and TRES results first revealed the energy transfer process from smaller QDs with higher energy to bigger QDs with lower energy in the PbS QD-doped glass.

10.
Opt Express ; 23(10): 13376-83, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-26074587

RESUMO

Topological insulator (TI) Bi2SeTe2 nanosheets with very regular hexagonal morphology were synthesized by a hydrothermal route. Open aperture (OA) z-scan method was performed to measure the saturable absorption (SA) characteristics of the as-prepared TI Bi2SeTe2 nanosheets. The measured modulation depth, saturation intensity and nonsaturable loss of the sample were 61.9%, 4.46 GW/cm2 and 4.5% respectively. An ultrafast intraband scattering time of ~50 fs was obtained through simulating the SA curve, which indicates the TI Bi2SeTe2 nanosheets may be a good candidate for mode-locking material.

11.
Opt Express ; 23(22): 28258-63, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26561096

RESUMO

Glass ceramic fibers containing Ni(2+) doped LiGa(5)O(8) nanocrystals were fabricated by a melt-in-tube method and successive heat treatment. Fiber precursors were prepared by drawing at high temperature where fiber core glass was melted while fiber clad glass was softened. After heat treatment, LiGa(5)O(8) nanocrystals were precipitated in the fiber core. Excited by 980 nm laser, efficient broadband near-infrared emission was observed in the glass ceramic fiber compared to that of precursor fiber. The melt-in-tube method can realize controllable crystallization and is suitable for fabrication of novel glass ceramic fibers. The Ni(2+)-doped glass ceramic fiber is promising for broadband optical amplification.

12.
Opt Express ; 22 Suppl 5: A1278-83, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25322182

RESUMO

A grating structure was inscribed in a tellurite glass after irradiation with high-repetition rate femtosecond laser pulses. High diffraction efficiency was obtained due to the large refractive index change, which was caused by the precipitation of Te crystals in the laser modified region. Two-dimensional multicolored arrays were generated by cascaded four-wave mixing (CFWM) together with the prefabricated grating structure, which showed much more superior than those induced by beam breakup.

13.
Opt Express ; 22(15): 17908-14, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25089411

RESUMO

We report on three-dimensional (3D) precipitation of ZnO crystals inside a silicate glass by a 500 kHz femtosecond pulse laser. The precipitation and distribution of ZnO crystals in glass are confirmed and analyzed by Raman spectra and Raman mapping. Mirco- luminescence is observed in the laser modified region when excited by femtosecond pulse laser or Xenon lamp. The effect of laser average power on the precipitation of the ZnO crystals has also been investigated. The possibility of 3D optical data storage using the observed phenomena is demonstrated.

14.
Phys Med Biol ; 69(5)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38271728

RESUMO

Objective. This study aims to develop and assess a tumor contraction model, enhancing the precision of ablative margin (AM) evaluation after microwave ablation (MWA) treatment for hepatocellular carcinomas (HCCs).Approach. We utilize a probabilistic method called the coherent point drift algorithm to align pre-and post-ablation MRI images. Subsequently, a nonlinear regression method quantifies local tumor contraction induced by MWA, utilizing data from 47 HCC with viable ablated tumors in post-ablation MRI. After automatic non-rigid registration, correction for tumor contraction involves contracting the 3D contour of the warped tumor towards its center in all orientations.Main results. We evaluate the performance of our proposed method on 30 HCC patients who underwent MWA. The Dice similarity coefficient between the post-ablation liver and the warped pre-ablation livers is found to be 0.95 ± 0.01, with a mean corresponding distance between the corresponding landmarks measured at 3.25 ± 0.62 mm. Additionally, we conduct a comparative analysis of clinical outcomes assessed through MRI over a 3 month follow-up period, noting that the AM, as evaluated by our proposed method, accurately detects residual tumor after MWA.Significance. Our proposed method showcases a high level of accuracy in MRI liver registration and AM assessment following ablation treatment. It introduces a potentially approach for predicting incomplete ablations and gauging treatment success.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Ablação por Cateter/métodos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
15.
Innov Aging ; 8(1): igad130, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38235486

RESUMO

Background and Objectives: This study systematically explores the association between community green space and preventing kidney failure among middle-aged and older adults in China, using street view data. Research Design and Methods: The 33 Chinese Community Health Study was used to conduct the analysis. We used street view data to assess street view green space (SVG) exposure and clearly distinguished the difference between grass (SVG-grass) and trees (SVG-tree). The normalized difference vegetation index (NDVI) was also used. Kidney failure was defined as a serum creatinine concentration of above 177 mol/L. We used multilevel logistic regression models (controlled for a series of covariates) to examine the associations between SVG and the odds of middle-aged and older adults having kidney failure. We also tested whether middle-aged and older adults from socioeconomically disadvantaged groups are likely to derive greater benefits from the effects of green space ("equigenesis"). Results: The results showed that both SVG (OR = 0.353; 95% CI = 0.171-0.731) and SVG-trees (OR = 0.327; 95% CI = 0.146-0.736) were negatively associated with the likelihood of middle-aged and older adults experiencing kidney failure, but there was no significant evidence of any links between either SVG-grass (OR = 0.567; 95% CI = 0.300-1.076) or the NDVI (OR = 0.398; 95% CI = 0.237-1.058) and kidney failure. Furthermore, the moderation analysis indicated that income and educational attainment have a moderating effect on the association between green space and the improvement of kidney health, which suggests that green space has greater positive effects on the kidney health of disadvantaged groups. Discussion and Implications: To reduce inequalities in relation to kidney disease through urban planning, policymakers are advised to provide more visual green space-especially trees-within the community and to focus in particular on socioeconomically disadvantaged population groups.

16.
Nat Commun ; 15(1): 1033, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310125

RESUMO

Phosphor-glass composites (PGC) are excellent candidates for highly efficient and stable photonic converters; however, their synthesis generally requires harsh procedures and long time, resulting in additional performance loss and energy consumption. Here we develop a rapid synthetic route to PGC within about 10 seconds, which enables uniform dispersion of Y3Al5O12:Ce3+ (YAG:Ce) phosphor particles through a particle self-stabilization model in molten tellurite glass. Thanks for good wettability between YAG:Ce micro-particles and tellurite glass melt, it creates an energy barrier of 6.94 × 105 zJ to prevent atomic-scale contact and sintering of particles in the melt. This in turn allows the generation of YAG:Ce-based PGC as attractive emitters with high quantum efficiency (98.4%) and absorption coefficient (86.8%) that can produce bright white light with luminous flux of 1227 lm and luminous efficiency of 276 lm W-1 under blue laser driving. This work shows a generalizable synthetic strategy for the development of functional glass composites.

17.
Adv Mater ; 36(23): e2313219, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38597361

RESUMO

The development of novel materials and structures for efficient second-order nonlinear micro/nano devices remains a significant challenge. In this study, the remarkable enhancement of second-harmonic generation (SHG) and cascaded sum frequency generation in whispering gallery mode microspheres made of surface-crystallized glass with a 6-µm Ba2TiSi2O8 crystal layer are demonstrated. Attributed to the core-shell design, the Ba2TiSi2O8 located on the surface can be efficiently coupled with whispering gallery modes, resulting in a highly efficient micron-scale cavity-enhanced second-order optical nonlinearity. Greatly enhanced SHG of the microcavity is observed, which is up to 80 times stronger than that of a non-resonant sample. Furthermore, owing to the wavelength non-selectivity of random quasi-phase matching, ultra-wideband SHG with a strong response ranging from 860 to 1600 nm and high-contrast polarization characteristics is demonstrated. The glass-ceramic-based microsphere cavity also boosts the cascading optical nonlinearity, manifested by a two-magnitude enhancement of cascaded sum frequency generation. This work delineates an efficient strategy for boosting nonlinear optical response in glass ceramics, which will open up new opportunities for applications in photonics and optical communications.

18.
Fundam Res ; 4(3): 624-634, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38933183

RESUMO

The pursuit of compact and integrated devices has stimulated a growing demand for multifunctional sensors with rapid and accurate responses to various physical parameters, either separately or simultaneously. Fluorescent fiber sensors have the advantages of robust stability, light weight, and compact geometry, enabling real-time and noninvasive signal detection by monitoring the fluorescence parameters. Despite substantial progress in fluorescence sensors, achieving multifunctional sensing in a single optical fiber remains challenging. To solve this problem, in this study, we present a bottom-up strategy to design and fabricate thermally drawn multifunctional fiber sensors by incorporating functional nanocrystals with temperature and pressure fluorescence responses into a transparent glass matrix. To generate the desired nanocrystal-in-glass composite (NGC) fiber, the fluorescent activators, incorporated nanocrystals, glassy core materials, and cladding matrix are rationally designed. Utilizing the fluorescence intensity ratio technique, a self-calibrated fiber sensor is demonstrated, with a bi-functional response to temperature and pressure. For temperature sensing, the NGC fiber exhibits temperature-dependent near-infrared emission at temperatures up to 573 K with a maximum absolute sensitivity of 0.019 K-1. A pressure-dependent upconversion emission is also realized in the visible spectral region, with a linear slope of -0.065. The successful demonstration of multifunctional NGC fiber sensors provides an efficient pathway for new paradigms of multifunctional sensors as well as a versatile strategy for future hybrid fibers with novel combinations of magnetic, optical, and mechanical properties.

19.
Adv Mater ; : e2404493, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718355

RESUMO

Optical waveguides fabricated in single crystals offer crucial passive/active optical components for photonic integrated circuits. Single crystals possess inherent advantages over their amorphous counterpart, such as lower optical losses in visible-to-mid-infrared band, larger peak emission cross-section, higher doping concentration. However, the writing of Type-I positive refractive index modified waveguides in single crystals using femtosecond laser technology presents significant challenges. Herein, this work introduces a novel femtosecond laser direct writing technique that combines slit-shaping with an immersion oil objective to fabricate low-loss Type-I waveguides in single crystals. This approach allows for precise control of waveguide shape, size, mode-field, and refractive index distribution, with a spatial resolution as high as 700 nm and a high positive refractive index variation on the order of 10-2, introducing new degrees of freedom to design and fabricate passive/active optical waveguide devices. As a proof-of-concept, this work successfully produces a 7 mm-long circular-shaped gain waveguide (≈10 µm in diameter) in an Er3+-doped YAG single crystal, exhibiting a propagation loss as low as 0.23 dB cm-1, a net gain of ≈3 dB and a polarization-insensitive character. The newly-developed technique is theoretically applicable to arbitrary single crystals, holding promising potential for various applications in integrated optics, optical communication, and photonic quantum circuits.

20.
Opt Express ; 21(16): 18943-8, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23938807

RESUMO

Thermal luminescence quenching behavior of a phosphor is essential for application in phosphor converted white light emitting diodes (pc-WLEDs) because the phosphor layer can be heated up to 473K in a working high power WLEDs. Here, we have confirmed indeed a red luminescence of Mn(4+) substituting for calcium sites rather than tetrahedral aluminum sites in CaAl(4)O(7):Mn which can be synthesized in pure phase even with boron acid as flux, and examined the low and high temperature luminescent properties in the range of 10 to 500K. We have revealed as well as thermal quenching mechanism that distorted octahedral Mn(4+) sites suffer severe thermal quenching. This work, thus, hints a strategy to find a new Mn(4+) phosphor with better resistance to thermal impact in the future.

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