[Study on the Analysis of the Proportion of Mixed Samples with Near Infrared Spectroscopy and Non-Negative Coefficients Regression].

In the process of practical production, it is important to accurately analyze the proportion of mixed samples with high speed, which plays a great role for quality control and formulation design in food and agricultural processing. Traditional solution is to build statistical model with a large number of representative samples, which is both labor-intensive and time-consuming. In this paper, the proportion of alcohol and acids mixed samples, and their dilute solution mixed samples(used carbon tetrachloride (CCl4) which has no near-infrared absorption characteristics as the solvent medium)，as well as sheet tobacco leaf mixed samples are respectively analyzed by using near infrared spectroscopy, SG smooth and non-negative coefficients regression, which verifies the feasibility of analyzing the proportion of the mixed samples. The results show that, the analytic proportion of transmission spectra of alcohol and acids according to non-negative coefficients regression is closer to actual molar proportion with result error less than 4%. The result of the dilute solution is much better with error less than 4%. The analytic proportion of diffuse reflectance spectra of sheet tobacco leaf according to non-negative coefficients regression is highly accurate with error less than 10%. In the meantime, it has a highly consistency between actual spectra and analytic spectra of mixed samples; and the result of F-test and T-test shows that there is no significant difference between them and the confidence level is 0.01. It has the reliability of analytical proportion in theory. With the spectral data of several pure samples, the proportion of mixed samples can be thus analyzed, which has a good application prospect for quality control and formulation design in food and agricultural processing.

[Determination of Wine Varieties with NIR and Fusion of Multiple Classifiers].

The conventional qualitative analysis of near infrared spectroscopy (NIR) commonly uses one single classification model. This paper focused on the fusion of multiple classifiers based on different single classifiers by using the fused classifier to determine different varieties of red-wines. NIR spectra of 170 red-wine samples were collected by using Fourier transform near-infrared spectrometer. Red-wine classification models were established respectively, based on PLS-DA, SVM, Fisher and Ada-Boost. Then these models were selected to obtain some different base classifiers according to Diversity Measure Feature Selective (DMFS). The highest accuracy rate of determining different varieties of red-wine test samples of four single base classifiers was up to 88.24%, and at the same time the lowest discriminant accuracy rate was 81.18%. At last, we got the fused classifier, which combined four base classifiers with weighted voting principle, and determined its test set again by using the fused classifier. The final classification accuracy rate for red-wine varieties increased to 92.94%, In contrast with one single classifier, the lowest misjudged number of fused classifiers decreased from 9 to 6.These results suggested that the performance of fused classifier is superior to one single classifier. It is feasible to use fused classifier combined with near infrared spectroscopy to determine different varieties of red-wines.

[Distribution of soil organic carbon in surface soil along a precipitation gradient in loess hilly area].

Along the 368-591 mm precipitation gradient, 7 survey sites, i.e. a total 63 investigated plots were selected. At each sites, woodland, grassland, and cropland with similar restoration age were selected to investigate soil organic carbon distribution in surface soil (0-30 cm), and the influence of factors, e.g. climate, soil depth, and land uses, on soil organic carbon distribution were analyzed. The result showed that, along the precipitation gradient, the grassland (8.70 g . kg-1) > woodland (7.88 g . kg-1) > farmland (7.73 g . kg-1) in concentration and the grassland (20.28 kg . m-2) > farmland (19.34 kg . m-2) > woodland (17.14 kg . m-2) in density. The differences of soil organic carbon concentration of three land uses were not significant. Further analysis of pooled data of three land uses showed that the surface soil organic carbon concentration differed significantly at different precipitation levels (P<0.00 1). Significant positive relationship was detected between mean annual precipitation and soil organic carbon concentration (r=0.838, P<0.001) in the of pooled data. From south to north (start from northernmost Ordos), i.e. along the 368-591 mm precipitation gradient, the soil organic carbon increased with annual precipitation 0. 04 g . kg-1 . mm-1, density 0.08 kg . m-2 . mm-1. The soil organic carbon distribution was predicted with mean annual precipitation, soil clay content, plant litter in woodland, and root density in farmland.

Effects of sodium tanshinone II A sulphonate on hypoxic pulmonary hypertension in rats in vivo and on Kv2.1 expression in pulmonary artery smooth muscle cells in vitro.

AIM OF THE STUDY: To investigate the effect of sodium tanshinone IIA sulphonate (STS), a water-soluble derivative of tanshinone II A, on hypoxic pulmonary hypertension (HPH) in rats and its underlying mechanisms. MATERIALS AND METHODS: Rats were exposed to hypoxia for two or three weeks, pretreated with or without STS. We detected mean pulmonary arterial pressure (mPAP), the ratio of right ventricle weight to left ventricle with septum weight [RV/(LV+S)], wall thickness and voltage-activated potassium channel (Kv) 2.1 mRNA level of pulmonary arteries (PAs), respectively, and the in vitro effects of STS on proliferation and Kv2.1 expression of cultured pulmonary smooth muscle cells (PASMCs) from normal rats. Cell proliferation was determined by 3-(4,5-dimethylthiazal-2-yl)-2,5-diphenyltetrazoliumbromiede (MTT) assay and direct cell counting. Kv2.1 mRNA and protein level were evaluated by reverse transcription-polymerase chain reaction and Western blot, respectively. RESULTS: Chronic hypoxia increased values of mPAP and RV/(LV+S) and inhibited Kv2.1 mRNA level in PAs. Three weeks' daily STS pretreatment inhibited the hypoxia-induced increased mPAP and RV/(LV+S), pulmonary arterial thickening and up-regulated Kv2.1 mRNA level in PAs. Further study in vitro showed that STS suppressed significantly hypoxia-induced PASMCs proliferation and inhibition of Kv2.1 expression in PASMCs. CONCLUSIONS: STS might play protective effects on HPH through decreasing mPAP, V/(LV+S) and inhibiting structural remodeling in distal PAs. The mechanism of these effects may be attributed to inhibiting PASMCs proliferation and stimulating Kv2.1 expression.

[Study on relativity of hypoxic pulmonary hypertension with levels of endothelin-1 and vascular endothelial growth factor in plasma of pulmonary artery and carotid artery].

AIM: To study the effects of endothelin-1 (ET-1) and vascular endothelial growth factor (VEGF) on the mechanism of hypoxic pulmonary hypertension (HPH). METHODS: We studied 4 groups of age-controlled male rats, i.e., normal control for 2 weeks group (N2), normal control for 3 weeks group (N3), exposed to hypoxia for 2 weeks group (H2) and for 3 weeks group (H3). Chronic HPH rat models were established by chronic hypobaric hypoxia [(10.0% +/- 0.5% O2] for 2 and 3 weeks, respectively. The rats were anesthetized and fixed, and the levels of mean pulmonary artery pressure (mPAP) and carotid arterial pressure (CAP) were measured using catheters by a microcomputer via transducers. The weight ratio of right ventricle (RV) and left ventricle and septum (LV + S) [RV/ (LV+S)] were determined. The contents of ET-1 in plasma of pulmonary artery and carotid artery and in homogenates of lung and systemic arteries were determined by radioimmunoassay, and the contents of VEGF in serum of pulmonary artery and carotid artery were determined by ABC-ELISA. RESULTS: HPH rat models were established successfully. Compared with control groups, the values of ET-1 were both enhanced in carotid artery and pulmonary artery plasma in model groups (P < 0.01). In the HPH groups, the level of pulmonary artery plasma ET-1 was significantly lower than that of carotid artery plasma, but just the reverse was ET-1 in control rats. The levels of ET-1 in homogenates of lungs from HPH models were significantly higher than those in homogenates of lungs from control groups (P < 0.01), and markedly higher than those in homogenates of systemic arteries from HPH rats (P < 0.01) SThe values of VEGF in serum of pulmonary artery from H3 group were significantly higher than those from control groups and H2 group (P < 0.01). In serum of carotid artery, the values of VEGF from the HPH models were higher than those from the control groups (P < 0.01). CONCLUSION: ET-1 and VEGF play important roles in the pathogenesis of HPH. The result that ET-1 concentration around pulmonary arteries was significantly higher than that around systemic arteries may be one of the mechanisms accounting for the different reaction of them to hypoxia.