Highly Sensitive and Selective Turn-on Fluorescent Probe for Hg2+ Based on Rhodamine 6G-Thiourea Conjugate.

An easily available novel fluorescent probe based on rhodamine 6G-thiourea conjugate (RGTU) has been synthesized. Upon mixed with Hg2+ in CH3CN-H2O (1:9, v/v), the dramatic enhancement of fluorescence intensity as well as the color change of the solution were observed. The presence of common coexisting alkali, alkaline earth, and transition metal ions showed small or no interference with the detection of Hg2+. The Job's plot and 1H NMR spectra indicated that Hg2+ induced spirolactam open to form 1:1 complex between RGTU and Hg2+.

A Sensitive and Selective Fluorescent Coumarin-Based Probe for Detection of Hypochlorite ion and its Application to Cellular Imaging.

Selective, sensitive fluorescent probes for ClO(-) are desirable due to the importance of ClO(-) in biological processes. Herein, a readily available turn-off fluorescent probe for ClO(-) is reported, which displays highly selectivity and sensitivity over other common anions and reactive oxygen/nitrogen. Moreover, it is able to detect ClO(-) in Ramos cells via cellular imaging.

[Study on an Algorithm for Near Infrared Singular Sample Identification Based on Strong Influence Degree].

Correcting sample selection and elimination of singular sample is very important for the quantitative and qualitative modeling of near infrared spectroscopy. However, methods for identification of singular sample available are generally based on data center estimates which require an experience decision threshold, this largely limit its recognition accuracy and practicability. Aiming at the low accuracy of the existing methods of singular sample recognition problem, this paper improves the existing metric-Leverage value and presents a new algorithm for near infrared singular sample identification based on strong influence degree. This metric reduces the dependence on the data center to a certain extent, so that the normal samples become more aggregation, and the distance between the singular samples and the normal samples is opened; at the same time, in order to avoid artificial setting threshold unreasonably according to experience, this paper introduces the concept of the jump degree in the field of statistics, and proposes an automatic threshold setting method to distinguish singular samples. In order to verify the validity of our algorithm, abnormal samples of 200 representative samples were eliminated in the calibration set with using Mahalanobis distance, Leverage-Spectral residual method and the algorithm presented in this paper respectively; then through partial least squares (PLS), the rest of the calibration samples were made quantitative modelings (took Nicotine as index), and the results of quantitative modelings were made a comparative analysis; besides, 60 representative testing samples were made a prediction through the modelings; at last, all the algorithms above were made a comparison with took Root Mean Square Error of Cross Validation (RMSECV), Correlation Coefficient (r) and Root Mean Square Error of Prediction (RMSEP) as evaluation Index. The experimental results demonstrate that the algorithm for near infrared singular sample identification based on strong influence degree significantly improves the accuracy of singular sample identificition over existing methods. With lower RMSECV (0.104), RMSEP (0.112) and higher r (0.983), it also contribute to boost the stability and prediction ability of the model.

[Comparative analysis of trace elements in five marine-derived shell TCM using multivariate statistical analysis].

A comparable study were carried out by determination of trace elements on five marine-derived shell traditional Chinese medicine (TCM) (Ostreae Concha, Haliotidis Concha, Margaritifera Concha, Meretricis Concha, and Arcae Concha), which were recorded in the Chinese Pharmacopoeia (2010 version). Seven trace elements in 51 batches of this type of shell TCM were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), combined with principal component analysis (PCA) methods. The content of element Se, which exhibited significant differences among different drugs, could be used as a key element to distinguish this type of drugs. Meanwhile, the contents of elements Co, Cu, Mo, and Ba in Haliotidis Concha, Co and As in Margaritifera Concha, Mo and As in Meretricis Concha, Mo, As, and Ba in Arcae Concha, and Zn in Meretricis Concha were relatively stable. In the PCA plot, Arcae Concha and Meretricis Concha could be efficiently distinguished from Ostreae Concha together with Haliotidis Concha, and Margaritifera Concha. The results also showed a correlation with their medicinal function. In conclusion, trace elements in marine-derived shell TCM could not be neglected for their quality control.

[Research on monitoring land subsidence in Beijing plain area using PS-InSAR technology].

In the present paper, the authors use permanent scatterers synthetic aperture radar interferometry (PS-InSAR) technique and 29 acquisitions by Envisat during 2003 to 2009 to monitor and analyze the spatial-temporal distribution and mechanism characterize of land subsidence in Beijing plain area. The results show that subsidence bowls have been bounded together in Beijing plain area, which covers Chaoyang, Changping, Shunyi and Tongzhou area, and the range of subsidence has an eastward trend. The most serious regional subsidence is mainly distributed by the quaternary depression in Beijing plain area. PS-Insar results also show a new subsidence bowl in Pinggu. What's more, the spatial and temporal distribution of deformation is controlled mainly by faults, such as Liangxiang-Shunyi fault, Huangzhuang-Gaoliying fault, and Nankou-Sunhe fault. The subsidence and level of groundwater in study area shows a good correlation, and the subsidence shows seasonal ups trend during November to March and seasonal downs trend during March to June along with changes in groundwater levels. The contribution of land subsidence is also influenced by stress-strain behavior of aquitards. The compaction of aquitards shows an elastic, plastic, viscoelastic pattern.

[Spatial-temporal evolution characterization of land subsidence by multi-temporal InSAR method and GIS technology].

Long-term over-exploitation of underground resources, and static and dynamic load increase year by year influence the occurrence and development of regional land subsidence to a certain extent. Choosing 29 scenes Envisat ASAR images covering plain area of Beijing, China, the present paper used the multi-temporal InSAR method incorporating both persistent scatterer and small baseline approaches, and obtained monitoring information of regional land subsidence. Under different situation of space development and utilization, the authors chose five typical settlement areas; With classified information of land-use, multi-spectral remote sensing image, and geological data, and adopting GIS spatial analysis methods, the authors analyzed the time series evolution characteristics of uneven settlement. The comprehensive analysis results suggests that the complex situations of space development and utilization affect the trend of uneven settlement; the easier the situation of space development and utilization, the smaller the settlement gradient, and the less the uneven settlement trend.

[Identification of marine-derived shell TCM by near infrared spectroscopy].

The identification of five marine-derived shell traditional Chinese medicine (TCM) recorded in the Chinese Pharmacopoeia were studied. Using near infrared technology (NIR) combined with principal component analysis (PCA) methods, Ostreae Concha, Haliotidis Concha, and Margaritifera Concha could be efficiently distinguished from Meretricis Concha together with Arcae Concha. In the first principal components, Ostreae Concha exhibited obvious differences with high loadings in 4 236, 5 263, 7 142 cm(-1) concerning to the contents of CaCO3 and H2O in the samples. Arcae Concha and Meretricis Concha displayed significant differences with others in the second principal components, which can be illustrated by high loadings in 5 000 -4 430 cm(-1) areas. It is indicated that the second principal components might be related to organics which contained NH and CH groups, for example proteins. Meanwhile, our data showed a correlation between the function of these shell TCM and their distribution in the PCA plot. These results suggested that organic components in marine-derived shell TCM could not be neglected for their quality control.

[The relationship between the variation rate of MODIS land surface temperature and AMSR-E soil moisture and its application to downscaling].

Using AMSR-E soil moisture, MODIS land surface temperature (Ts) and vegetation index product, the authors discuss the relationship between the variation rate of land surface temperature and surface soil moisture. Selecting the plains region of central United States as the study area, the authors propose the distribution triangle of the variation rate of land surface temperature and soil moisture. In the present paper, temperature variation and vegetation index (TVVI), a new index containing the information of temperature variation and vegetation, is introduced. The authors prove that TVVI and soil moisture show a steady relationship of exponential function; and build a quantitative model of soil moisture(SM) and instantaneous surface temperature variation (VTs). The authors later achieve downscaling of AMSR-E soil moisture data, through the above stated functional relationships and high-resolution MODIS data. Comparison with measured data on ground surface indicates that this method of downscaling is of high precision

[Study on the nonlinear characteristics of the mixed pixel's reflectance in hyperspectral space].

Under the experimental condition of the 50 degree incidence zenith angle and 45 degree detection azimuth, 24 groups of reflectance spectral of the mixed pixel of lotus and water body acquired using the reflex platform and FieldSpec 3 Hi-Res portable spectrum instrument. The hyperspectral space was built based on the reflectance character. The relationship between similarity and the index of lotus area ratio was analyzed using the linear, logarithm and quadratic curve fitting, and the goodness of fitting is 63.6%, 76.2% and 82.9% respectively. According to the real relationship of the mixed pixel spectral vector and the reference spectral, the best fitting model has nonlinear characteristics. The idea that the mixed pixel may have the critical value was proposed on the base of the analysis. The research result will help understand the mixed pixel further, and provide a new direction for unmixing the mixed pixel.

[Study on reflectance spectra morphological character of the hyperspectral mixed pixels at different component proportion].

Under the experimental condition, the hyperspectral reflectance spectra of the mixed pixel of lotus and water body were acquired using the multi-angles dichotic reflex platform and ASD spectrum instrument. The reflectance spectral morphological character index variation of the hyperspectral mixed pixel at different component proportion was analyzed. The conclusions are as follows: the correlation between these morphological indexes was obvious, and the best morphological index was chosen by removing the index whose R2 was greater than 0.5 (R is correlation coefficient); the variation of different morphological index was obvious; the cluster analysis shows that there was a critical value in the progress of the transformation from the pure pixel (water) to mixed pixel. If the proportion was less than the critical value, the reflectance spectra reflected the reflection characteristics of pure pixel; otherwise, it was the reflection of characteristics of mixed pixel.

[The impact of load density differences on land subsidence based on build-up index and PS-InSAR technology].

The excessive mining for underground water is the main reason inducing the land subsidence in Beijing, while, increasing of load brought by the urban construction aggravate the local land subsidence in a certain degree. As an international metropolis, the problems of land subsidence that caused by urban construction are becoming increasingly highlights, so revealing the relationship between regional load increase and the response of land subsidence also becomes one of the key problems in the land subsidence research field. In order to analyze the relationship between the load changes in construction and the land subsidence quantitatively, the present study selected the TM remote sensing image covering Beijing plain and used Erdas Modeler tool to invert the index based on building site (IBI), acquired the spatial and temporal change information in research area further; Based on results monitored by PS-InSAR (permanent scatterer interferometry) and IBI index method, and combined with the GIS spatial analysis method in the view of pixels in different scales, this paper analyzes the correlation between typical area load change and land subsidence, The conclusions show that there is a positive correlation between the density of load and the homogeneity of subsidence, especially in area which has a high sedimentation rate. Owing to such characteristics as the complexity and hysteretic nature of soil and geological structure, it is not obvious that the land subsidence caused by the increase of load in a short period. But with the increasing of local land load made by high density buildings and additional settlement of each monomer building superposed with each other, regional land subsidence is still a question that cannot be ignored and needs long-term systematic research and discussion.

[Tumor-suppression effect of polyactin A combined with GM-CSF, TNF-alpha and IL-4 on cord blood mononuclear cells].

OBJECTIVE: To investigate the tumor-suppression effect of PA combined with GM-CSF, TNF-alpha and IL-4 on cord blood mononuclear cells (CBMC). METHODS: The mononuclear cells were isolated from human umbilical cord blood and cultured with polyacttin A (PA), GM-CSF + TNF-alpha + IL-4 (GTI), and GTI + PA (GTIP) respectively. Six days later, surface antigen expression of the cultured cells, including CD1a and CD83, which were the specialized markers of dendritic cell (DC), were analyzed by immunohistochemistry technique. The CBMC were cultured with GTI for 24 h to enhance DC, then were added apoptotic/necrotic Hela/HepG2 tumor cells, and finally PA was co-cultured. The antitumor cytotoxicity of CBMC was measured by MTT assay. RESULTS: After the culture, CD1a and CD83 positive cell rates of the PA group inreased significantly, reaching (19.63 +/- 3.61)%, (9.28 +/- 4.31) % respectively, much higher than that of the control, but lower than that of the GTI group. The killing rate to the tumor cells of CBMC cultured with GTIP increased remarkably, much higher than the control, GTI and PA groups. After tumor antigens were added to the CBMC of GTIP group (GTIP + Tc), the killing rate increased. CONCLUSION: PA not only promotes the proliferation and maturation of cord blood derived DC, but also improves the tumor-suppression effect of CBMC cultured with GTI.