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1.
J Inflamm Res ; 17: 4055-4064, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939122

RESUMO

Objective: Osteitis is more prevalent in patients with chronic rhinosinusitis with nasal polyps (CRSwNP), making the disease refractory and prone to recurrence. However, the pathophysiologic mechanism of osteitis formation in CRS has not been fully elucidated, and this study aimed to further elucidate the association of eosinophils and type 2 inflammatory mediators with osteitis in patients with CRSwNP. Methods: This retrospective study collected clinical data on 125 cases of CRSwNP. The participants were categorized into two groups based on the presence or absence of osteitis in their sinus CT scan. The groups were classified as the osteitis group and the non-osteitis group. The clinical baseline data, type 2 inflammatory mediators, and eosinophils were compared between the two groups. The correlation between these factors and the Global Osteitis score scale (GOSS) was also evaluated. Results: There were 69 cases in the osteitis group and 56 cases in the non-osteitis group of CRSwNP patients. The prevalence of concomitant asthma (P=0.009), SNOT-22 score, LUND-MAKAY score, and LUND-KEDENY score were significantly higher in the osteitis group than in the non-osteitis group (All P values were < 0.001); the absolute values of IL-13 (P<0.001), periosteal proteins (P<0.001), and tissue eosinophils (P < 0.05) were significantly higher in the osteitis group as compared with the non-osteitis group. Logistic regression analysis showed that IL-13 and periosteal proteins were risk factors for CRSwNP osteitis (P<0.001). ROC curve analysis revealed that IL-13 had the highest predictive value (AUC=0.786) with a cut-off value of 5.8059 pg/mL, the sensitivity of 58.0%, and a specificity of 89.3% respectively. Conclusion: Osteitis could indicate the more severe symptoms of chronic rhinosinusitis with nasal polyps (CRSwNP), and elevated IL-13, periosteal proteins, and tissue eosinophils are risk factors for osteitis formation in patients with CRSwNP.

2.
Adv Mater ; 36(19): e2204884, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38374724

RESUMO

Phonon polaritons, quasiparticles arising from strong coupling between electromagnetic waves and optical phonons, have potential for applications in subdiffraction imaging, sensing, thermal conduction enhancement, and spectroscopy signal enhancement. A new class of phonon polaritons in low-symmetry monoclinic crystals, hyperbolic shear polaritons (HShPs), have been verified recently in ß-Ga2O3 by free electron laser (FEL) measurements. However, detailed behaviors of HShPs in ß-Ga2O3 nanostructures still remain unknown. Here, by using monochromatic electron energy loss spectroscopy in conjunction with scanning transmission electron microscopy, the experimental observation of multiple HShPs in ß-Ga2O3 in the mid-infrared (MIR) and far-infrared (FIR) ranges is reported. HShPs in various ß-Ga2O3 nanorods and a ß-Ga2O3 nanodisk are excited. The frequency-dependent rotation and shear effect of HShPs reflect on the distribution of EELS signals. The propagation and reflection of HShPs in nanostructures are clarified by simulations of electric field distribution. These findings suggest that, with its tunable broad spectral HShPs, ß-Ga2O3 is an excellent candidate for nanophotonic applications.

3.
Nat Commun ; 13(1): 4901, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987993

RESUMO

Understanding thermal transport across metal/semiconductor interfaces is crucial for the heat dissipation of electronics. The dominant heat carriers in non-metals, phonons, are thought to transport elastically across most interfaces, except for a few extreme cases where the two materials that formed the interface are highly dissimilar with a large difference in Debye temperature. In this work, we show that even for two materials with similar Debye temperatures (Al/Si, Al/GaN), a substantial portion of phonons will transport inelastically across their interfaces at high temperatures, significantly enhancing interface thermal conductance. Moreover, we find that interface sharpness strongly affects phonon transport process. For atomically sharp interfaces, phonons are allowed to transport inelastically and interface thermal conductance linearly increases at high temperatures. With a diffuse interface, inelastic phonon transport diminishes. Our results provide new insights on phonon transport across interfaces and open up opportunities for engineering interface thermal conductance specifically for materials of relevance to microelectronics.

4.
Chemosphere ; 242: 125168, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31678850

RESUMO

Plants have evolved effective strategies to cope with heavy metals Cd toxicity, but the regulatory mechanism underlying Cd tolerance and accumulation are still poorly understood. miR156 has been shown to be the master regulator of development and stress response in plants. However, whether miR156 is also involved in plant Cd stress response remains unknown. Here, we show that plants overexpressing miR156 (miR156OE) accumulated significantly less Cd in the shoot, and conferred enhanced tolerance to Cd stress. Plants with a knocked-down level of miR156 (MIM156) were sensitive to Cd stress, and accumulated significantly higher Cd. Under Cd stress, miR156OE had significantly longer primary root length, higher biomass and chlorophyll content, increased activities of antioxidative enzymes and lower levels of endogenous reactive oxygen species (ROS), while MIM156 had the opposite phenotype. To investigate the underlying mechanism of miR156-mediated Cd stress response in Arabidopsis, we profiled the expression of several Cd transporter genes. The expression of Cd uptake transporter of AtZIP1、AtZIP2 and vacuole segregated transporter AtABCC1 was significantly elevated in miR156OE, whereas it was significantly reduced in MIM156. MIM156 also led to an elevated level of AtHMA4 responsible for transporting Cd from the root to the shoot. Our results indicate that miR156 acts as a positive regulator of plant tolerance to Cd stress by modulating ROS levels and Cd uptake/transport genes expression. Therefore, our study adds a new layer of regulatory mechanism for Cd transport and tolerance in plants, and provides a perspective to regulate Cd transport artificially by modulating plant vegetative growth and development using miR156.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Bioacumulação , Cádmio/metabolismo , MicroRNAs/genética , Poluentes do Solo/metabolismo , Arabidopsis/genética , Transporte Biológico , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 169-76, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228762

RESUMO

Spectral indices (SIs) method has been widely applied in the prediction of vegetation biochemical parameters. Take the diversity of spectral response of different sensors into consideration, this study aimed at researching spectral scale effect of SIs for estimating vegetation chlorophyll content (VCC). The 5 nm leaf reflectance data under 16 levels of chlorophyll content was got by the radiation transfer model PROSPECT and then simulated to multiple bandwidths spectrum (10-35 nm), using Gaussian spectral response function. Firstly, the correlation between SIs and VCC was studied. And then the sensitivity of SIs to VCC and bandwidth were analyzed and compared. Lastly, 112 samples were selected to verify the results above mentioned. The results show that Vegetation Index Based on Universal Pattern Decomposition Method (VIUPD) is the best spectral index due to its high sensitivity to VCC but low sensitivity to bandwidth, and can be successfully used to estimate VCC with coefficient of determination R2 of 0.99 and RMSE of 3.52 µg x cm(-2). Followed by VIUPD, Normalized Difference Vegetation Index (NDVI) and Simple Ratio Index (SRI) presented a comparatively good performance for VCC estimation (R2 > 0.89) with their prediction value of chlorophyll content was lower than the true value. The worse accuracy of other indices were also tested. Results demonstrate that spectral scale effect must be well-considered when estimating chlorophyll content, using SIs method. VIUPD introduced in the present study has the best performance, which reaffirms its special feature of comparatively sensor-independent and illustrates its potential ability in the area of estimating vegetation biochemical parameters based on multiple satellite data.


Assuntos
Clorofila/análise , Folhas de Planta/química , Análise Espectral , Modelos Teóricos , Análise de Regressão
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 975-81, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197586

RESUMO

Spectral index method was widely applied to the inversion of crop chlorophyll content. In the present study, PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage of winter wheat. Then the measured spectra were resampled to simulate TM multispectral data and Hyperion hyperspectral data respectively, using the Gaussian spectral response function. We chose four typical spectral indices including normalized difference vegetation index (NDVD, triangle vegetation index (TVI), the ratio of modified transformed chlorophyll absorption ratio index (MCARI) to optimized soil adjusted vegetation index (OSAVI) (MCARI/OSAVI) and vegetation index based on universal pattern decomposition (VIUPD), which were constructed with the feature bands sensitive to the vegetation chlorophyll. After calculating these spectral indices based on the resampling TM and Hyperion data, the regression equation between spectral indices and chlorophyll content was established. For TM, the result indicates that VIUPD has the best correlation with chlorophyll (R2 = 0.819 7) followed by NDVI (R2 = 0.791 8), while MCARI/OSAVI and TVI also show a good correlation with R2 higher than 0.5. For the simulated Hyperion data, VIUPD again ranks first with R2 = 0.817 1, followed by MCARI/OSAVI (R2 = 0.658 6), while NDVI and TVI show very low values with R2 less than 0.2. It was demonstrated that VIUPD has the best accuracy and stability to estimate chlorophyll of winter wheat whether using simulated TM data or Hyperion data, which reaffirms that VIUPD is comparatively sensor independent. The chlorophyll estimation accuracy and stability of MCARI/OSAVI also works well, partly because OSAVI could reduce the influence of backgrounds. Two broadband spectral indices NDVI and TVI are weak for the chlorophyll estimation of simulated Hyperion data mainly because of their dependence on few bands and the strong influence of atmosphere, solar altitude, viewing angle of sensor, background and so on. In conclusion, the stability and consistency of chlorophyll estimation is equally important to the estimation accuracy by spectral index method. VIUPD introduced in the study has the best performance to estimate winter wheat chlorophyll, which illustrates its potential ability in the area of estimating vegetation biochemical parameters.


Assuntos
Clorofila/análise , Folhas de Planta/química , Análise Espectral , Triticum/química , Solo
7.
Opt Express ; 17(18): 16073-80, 2009 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-19724607

RESUMO

A green light at 556 nm is generated by direct frequency doubling of a fiber laser at 1111.6 nm with a periodically poled MgO:LiNbO3 waveguide. We have investigated optical inhomogeneities by measuring the temperature tuning curve of second harmonic generation, and the obtained parameters are used for identifying the uniformity of the waveguide. The thermal dephasing could be diminished by adjusting the crystal temperature, and the conversion efficiency was maximized. Finally, an output power of 111.8 mW at 556 nm was generated with 213 mW of coupled fundamental light under optimum conditions, which corresponds to 52.5% conversion efficiency.

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