Two-color resonant two-photon mass-analyzed threshold ionization （MATI） spectroscopy was used to record the vibrationally resolved cation spectra of the selected rotamers of p- ethoxyphenol. The adiabatic ionization...Two-color resonant two-photon mass-analyzed threshold ionization （MATI） spectroscopy was used to record the vibrationally resolved cation spectra of the selected rotamers of p- ethoxyphenol. The adiabatic ionization energies of the trans and cis rotamers are determined to be 61565±5 and 61670±5 cm^-1, which are less than that of p-methoxyphenol by 645 and 643 cm^-1, respectively. Analysis on the MATI spectra of the selected rotamers of p-ethoxyphenol cation shows that the relative orientation of the ethoxy group has little effect on the in-plane ring vibrations. The low-frequency OC2H5 bending vibrations appear to be active for both forms of the cation.展开更多
Under consideration that the profiles of bands at close wavelengths are quite similar and the curvelets are good at capturing profiles, a junk band recovery algorithm for hyperspectral data based on curvelet transform...Under consideration that the profiles of bands at close wavelengths are quite similar and the curvelets are good at capturing profiles, a junk band recovery algorithm for hyperspectral data based on curvelet transform is proposed. Both the noisy bands and the noise-free bands are transformed via curvelet band by band. The high frequency coefficients in junk bands are replaced with linear interpolation of the high frequency coefficients in noise-flee bands, and the low frequency coefficients remain the same to keep the main spectral characteristics from being distorted. Jutak bands then are recovered after the inverse curvelet transform. The performance of this method is tested on the hyperspectral data cube obtained by airborne visible/infrared imaging spectrometer （AVIRIS）. The experimental results show that the proposed method is superior to the traditional denoising method BayesShrink and the art-of-state Curvelet Shrinkage in both roots of mean square error （RMSE） and peak-signal-to-noise ratio （PSNR） of recovered bands.展开更多
In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regul...In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regulation mechanism and destabilized enhanced green fluorescent protein （d2EGFP） reporter gene technique. The positive cell clone was confirmed by real-time polymerase chain reaction （PCR） and imaging analysis. To assess the value of this model, we screened over 2000 high performance liquid chromatography （HPLC）-fractionated samples from the ethanol extracts of Chinese medicinal herbs. Six fractions （isolated from Panax japonicus, Veratrum nigrum, Phellodendron amurense, Fructus Aurantii lmmaturus, Chaenomeles speciosa, and Dictamnus dasycarpus） showed significant effects on active reporter gene expression, three of which （isolated from Phellodendron amurense, Fructus Aurantii lmmaturus, and Chaenomeles speciosa） were selected for further concentration response analysis and the half maximal effective concentration （EC1/2 max） values were 4.2, 2.7, and 4.8 μg/ml, respectively. Therefore, this reporter gene assay was suitable for screening β2-adrenoceptor agonists. The results suggest that the six herbal extracts are the possible agonists of β2-adrenoceptor.展开更多
文摘Two-color resonant two-photon mass-analyzed threshold ionization （MATI） spectroscopy was used to record the vibrationally resolved cation spectra of the selected rotamers of p- ethoxyphenol. The adiabatic ionization energies of the trans and cis rotamers are determined to be 61565±5 and 61670±5 cm^-1, which are less than that of p-methoxyphenol by 645 and 643 cm^-1, respectively. Analysis on the MATI spectra of the selected rotamers of p-ethoxyphenol cation shows that the relative orientation of the ethoxy group has little effect on the in-plane ring vibrations. The low-frequency OC2H5 bending vibrations appear to be active for both forms of the cation.
基金Project(10871231) supported by the National Natural Science Foundation of China
文摘Under consideration that the profiles of bands at close wavelengths are quite similar and the curvelets are good at capturing profiles, a junk band recovery algorithm for hyperspectral data based on curvelet transform is proposed. Both the noisy bands and the noise-free bands are transformed via curvelet band by band. The high frequency coefficients in junk bands are replaced with linear interpolation of the high frequency coefficients in noise-flee bands, and the low frequency coefficients remain the same to keep the main spectral characteristics from being distorted. Jutak bands then are recovered after the inverse curvelet transform. The performance of this method is tested on the hyperspectral data cube obtained by airborne visible/infrared imaging spectrometer （AVIRIS）. The experimental results show that the proposed method is superior to the traditional denoising method BayesShrink and the art-of-state Curvelet Shrinkage in both roots of mean square error （RMSE） and peak-signal-to-noise ratio （PSNR） of recovered bands.
基金Project (No. 30873103) supported by the National Natural Science Foundation of China
文摘In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regulation mechanism and destabilized enhanced green fluorescent protein （d2EGFP） reporter gene technique. The positive cell clone was confirmed by real-time polymerase chain reaction （PCR） and imaging analysis. To assess the value of this model, we screened over 2000 high performance liquid chromatography （HPLC）-fractionated samples from the ethanol extracts of Chinese medicinal herbs. Six fractions （isolated from Panax japonicus, Veratrum nigrum, Phellodendron amurense, Fructus Aurantii lmmaturus, Chaenomeles speciosa, and Dictamnus dasycarpus） showed significant effects on active reporter gene expression, three of which （isolated from Phellodendron amurense, Fructus Aurantii lmmaturus, and Chaenomeles speciosa） were selected for further concentration response analysis and the half maximal effective concentration （EC1/2 max） values were 4.2, 2.7, and 4.8 μg/ml, respectively. Therefore, this reporter gene assay was suitable for screening β2-adrenoceptor agonists. The results suggest that the six herbal extracts are the possible agonists of β2-adrenoceptor.
