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Based on the Si' lnikov theorem, this paper proposed a new three-dimensional square chaotic system, which had tow equilibrium poits. There was hyperbolic saddle focus. The formation mechanism showed that this chaotic system had Smale horseshoes (homoclinic chaos). Under satisfying the homoclinic Si' lnikov theorem, the large number of parameter values, which could be found, made that the system was chaotic state. Numerical simulation results show the effectiveness of the theoretical results. Finally, Smale horseshoses had been found in the system using undetermined-coefficient method, and it was chaotic in the sense of Si' lnikov. [ABSTRACT FROM AUTHOR]

A low temperature treatment in rice booting key period was executed on the north slope of Changbai Mountains to construct the impact model of low temperature on rice shell rate, and to reveal the effects of low temperature at different stages of rice young panicle on seed setting. The results showed that effects of low temperature in the young ear formation stage on rice shell rate generally followed the logarithmic function, the lower the temperature was, the greater the temperature influence coefficient was, and the longer the low temperature duration was, the higher rice shell rate was. The seed setting rate was most sensitive to low temperature in the middle time of booting stage (the period from formation to meiosis of the pollen mother cell), followed by the early and later stages. During the booting stage, with 1 ℃ decrease of daily temperature under 2-, 3- and 5-day low temperature treatments, the shell rate increased by 0.5, 1.7 and 4.3 percentage, respectively, and with 1 ℃ decrease of daily minimum temperature, the shell rate increased by 0.4,1.8 and 4.5 percentage, respectively. The impact of 2-day low temperature was smaller than that of 3 days or more. The impact of accumulative cold-temperature on the shell rate followed exponential function. In the range of harmful low temperature, rice shell rate increased about 8.5 percentage with the accumulative cold-temperature increasing 10 ℃·d. When the 3 days average temperature dropped to 21.6, 18.0 and 15.0 ℃, or the 5 days average temperature dropped to 22.0, 20.4 and 18.5 ℃, or the accumulative cold-temperature was more than 8, 19, 26 ℃·d, the light, moderate and severe booting stage chilling injury would occur, respectively. In Northeast China, low temperature within 2 d in rice booting stage might not cause moderate and severe chilling injury.

For determination of elements in the leaves of Prunus mongolica, the samples were digested by nitric acid-perchloric. The contents of Ca, Mg, Fe, Mn, Cu, Zn, Al, Sr, Sn and Pb in the leaves of Prunus mongolica were determined by ICP-AES, at the same time a blank experiment was carried out. The results showed that the recovery rate of the ten elements was between 93% and 110%, and the relative standard deviation was between 0.33% and 2.94%. This method is fast, simple and accurate.

In quantitative analysis of spectral data, noises and background interference always degrade the accuracy of spectral feature extraction. The wavelet transform is multi-scale decomposition used to reduce the noise and improve the analysis precision. On the other hand, the wavelet transform denoising is often followed by destroying the efficiency information. The present research introduced two indexes to control the scale of decomposition, the smoothness index (SI) and the time shift index (TSI). When the parameters satisfied TSI < 0.01 and SI > 0.100 4, the noise of spectral characteristic was reduced. In the meanwhile, the reflection peaks of biochemical components were reserved. Through analyzing the correlation between denoised spectrum and chlorophyll content, some spectral characteristics parameters reflecting the changing tendency of chlorophyll content were chosen. Finally, the partial least squares regression (PLSR) was used to develop the prediction model of the chlorophyll content of tomato leaf. The result showed that the predictiong model, which used the values of absorbance at 366, 405, 436, 554, 675 and 693 nm as input variables, had higher predictive ability (calibration coefficient was 0. 892 6, and validation coefficient was 0.829 7) and better potential to diagnose tomato growth in greenhouse.

Objective: To observe the promoting consciousness effect of electroacupuncture combined with routine western medicine therapy on the patient with coma caused by craniocerebral trauma., Methods: Thirty-two cases were randomly divided into an acupuncture-medication group treated with electroacupuncture at Neiguan (PC 6) and Quze (PC 3) and routine western medicine, and a control group treated with routine western medicine, 16 cases in each group. Glasgow (GCS) scores were assessed after treatment for 7 sessions and 30 sessions respectively and the promoting consciousness rate was observed., Results: After treatment of 7 sessions, GCS score was 6.88 +/- 1.63 in the acupuncture-medication group and 5.25-1.65 in the control group with a significant difference between the two groups (P < 0.05); after treatment of 7 sessions, the promoting consciousness rate was 25.0% in the acupuncture-medication group and 0 in the western medicine group, and after treatment for 30 sessions, the promoting conscious ness rate was 81. 3% in the acupuncture-medication group and 43.8% in the western medicine group with a signifi cant difference between the two groups (P < 0.05)., Conclusion: Electroacupuncture at Neiguan (PC 6) and Quze (PC 3) combined with western medicine has a good promoting consciousness effect in the patient with coma caused by craniocerebral trauma, which is better than that of simple western medicine.

Based on MODIS images and by using the algorithm of maximum value composite (MVC), the monthly vegetation indices (VIs) in 2005 in Hunan Province were obtained. Through the analysis of the MODIS VIs, Hunan Province was divided into six districts to describe the spatial distribution of the VIs, and by using the monthly mean temperature and rainfall data collected from 5 climatic monitoring stations in this province, the temporal variation of the VIs was analyzed. The results showed that the spatial distribution of MODIS VIs was positively correlated with vegetation cover, and appeared regional characteristics. The MODIS VIs varied with season, and the curves of their monthly mean values were downwards opening quadratic parabolas, with the maximum appeared in July. The value of MODIS EVI was smaller than that of MODIS NDVI. MODIS VI was mainly affected by monthly mean temperature, but this effect was decreased with decreasing latitude. The variation pattern of MODIS EVI was more apparent than that of MODIS NDVI, i. e. , the quadratic parabola of MODIS EVI was smoother, going gradually from minimum to maximum and then going down, while that of MODIS NDVI had tiny fluctuations on both sides of the maximum point.

Aim: To develop a near-infrared diffuse reflectance analysis (NIRDRA) method for rapid noninvasive quantitative determination of ambroxol hydrochloride in half-finished product particles and non-blister-packed, blistered tablets., Methods: All spectra were measured with a Fourier transform spectrometer equipped with a PbS and a InGaAs detector, an external integrating sphere, a rotating sample cup, and a fibre-optic probe for reflectance measurements. All samples were scanned from 12,000 cm-1 to 4,000 cm-1, and each sample spectrum was obtained as an automatic mean of 64 scans. No spectrum pre-processing method was used, and spectral regions, 4,602-4,247, 12,000-7,498 and 6,102-5,446, 12,000-5,446 cm-1 were selected to develope mathematical models by partial least square method for half-finished product particles and non-blister-packed, blistered tablets samples, respectively., Results: The optimal rank and mean square error determined for half-finished product particles and non-blister-packed, blistered tablets samples by cross validation method all was 6 and 0.306, 0.972 and 1.492, respectively, the average recovery was 100%, 100% and 102% respectively; and the RSD was 1.17%, 1.70% and 1.78% respectively., Conclusion: Results showed that the NIRDRA method was rapid, simple, noninvasive and sensitive, and it can be applied to assay the content of ambroxol hydrochloride in half-finished product particles non-blister-packed and blistered tablets.

Aim: To determine the molecular weight and first-order structure of somatostatin., Methods: The molecular weight of somatostatin was determined by electrospray ionization mass spectrometry. Somatostatin was deoxidized by 2-mercaptoethanol. A series of typical fragment ions of deoxidized product were obtained by insource collision-induced dissociation (CID)., Results: The m/z of quasi-molecular ion [M + H]+ of somatostatin was 1,637.8 and [M + Na]+ was 1,659.5. The m/z of double-charge ion [M + 2H]2+ was 819.5 and [M + H + Na]2+ was 830.3. It showed that the molecular weight of somatostatin was 1,636.7. The y and b series of fragment ions of deoxidized product were obtained by adjusting the fragmentor voltage. It was determined that the first-order structure of deoxidized product of somatostatin was A-G-C-K-N-F-F-W-K-T-F-T-S-C., Conclusion: The molecular weight and first-order structure of somatostatin were confirmed.

Aim: To establish a RP-HPLC method for determination of cyclovirobuxine D., Methods: Cyclovirobuxine D reacted with a derivative reagent 1-naphthyl isocyanate in chloroform to form fluorescence derivatives, stopped the reaction by adding the mobile phase and then directly injected the solution into the chromatograph to seperate it by RP-HPLC. The analysis was carried out on C18 column, the mobile phase is methanol-water (85:15), the excitation wavelength was set at 305 nm, emission at wavelength 385 nm, and the flow rate was 1 mL.min-1. The effect of several factors including the reaction medium, temperature, time and amount of 1-naphthyl isocyanate on the yield of the derivatization was also investigated systematically., Results: A simple and rapid RP-HPLC method for the simultaneous isolation and analysis of cyclovirobuxine D and its related substances was developed, and the absence of interference between the derivative peak responses of cyclovirobuxine D and its related substances were verified by UV diode array detecter and MS. The linearity was obtained from 0.75 microgram.mL-1 to 2.5 micrograms.mL-1 of cyclovirobuxine D derivatives with a correlation coefficient of 0.9991. The detection limit of cyclovirobuxine D derivative was 1 ng.mL-1, the repeatability of derivatization was good with relative standard derivation no more than 1.2% and derivative was stable within 48 h. The method described conforms to the validation of China Pharmacopiea compendial methods used for pharmaceutical products in general., Conclusion: The established method is proved to be reliable quantitative method for the quality control of cyclovirobuxine D.