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Objective: To solve the problems of poor accuracy and low sorting efficiency of the existing string fruits in robot sorting. Methods: Based on the structure of the high-speed parallel food sorting system, the improved SURF algorithm and the improved RANSAC algorithm were combined to locate the grab points of the food sorting robot, and a three-dimensional grab model was established to realize the automatic and stable grab of string fruits. Taking grapes as an example, the superiority and accuracy of the proposed method were verified by experiments. Results: Compared with the conventional method, the proposed method improved the average capture success rate by about 15.00% and the average capture time by 0.101 s. Conclusion: The food sorting robot can effectively improve the accuracy of the positioning of the holding points of string fruits, and has a high success rate.

Objective To investigate the role of proline-rich protein tyrosine kinase (Pyk2) in angiotensin Ⅱ(Ang Ⅱ)-induced cardiac hypertrophy and the underlying mechanism in rat. Methods Primary rat cardio-myocytes were isolated from rats and randomly divided into control group, Ang Ⅱ induction group (the dose of Ang Ⅱ was 100 nmol/L, cardiomyocytes were stimulated in the cell culture dish for 24 hours), Pyk2 inhibitor PF-431396 group (the dose of PF-431396 was 10 μmol/L, added to the cell culture dish 30 minutes in advance before Ang Ⅱ stimulation) and Ang Ⅱ induction group intervened by PF-431396 (the dose of Ang Ⅱ was 100 nmol/L, the dose of PF-431396 was 10 μmol/L). The size of cardiomyocytes was measured by α-actinin fluorescence staining. RT-qPCR was performed to detect the mRNA level of hypertrophic markers (ANP and β-MHC) in cardiomyocytes. The expressions of p-Pyk2, Pyk2 and p53 in cardiomyocytes were detected by Western blot analysis. Results Ang Ⅱ stimulation increased the surface area of cardiomyocytes and the mRNA level of hypertrophic markers(P＜0.05). In addition, the proteins of p-Pyk2 and p53 were increased(P＜0.05). However, after treatment of Pyk2 inhibitor PF-431396, moycardial hypertrophy was significantly improved and the protein level of Pyk2 and p53 decreased(P＜0.05). Conclusions Pyk2 promotes cardiomyocyte hypertrophy in rat induced by Ang Ⅱ through the p53 signaling pathway.

Objective To investigate the effects of metformin on the proliferation, apoptosis and migration ability of human hepatocellular carcinoma cells HCCLM3. Methods HCCLM3 cells were treated with different concentrations of metformin. Cell proliferation was assessed by CCK-8 assay. The expression of related apoptosis genes, Bax and Bcl-2 were determined by RT-PCR. Cell migration was determined by scratch experiment. Results Metformin decreased the proliferation of HCCLM3 cells in a dose-dependent and time-dependent manner and the cell proliferation inhibition rate was significantly higher than the control group (P < 0.05) . The migration of HCCLM3 was inhibited when the concentration of metformin reaches 10mmol/L. The expression of Bax mRNA was up-regulated, while Bcl-2 was down-regulated after 48h treated. Conclusion Metformin can inhibit HCCLM3 cell proliferation and migration, and affect the expression of apoptosis related gene Bax and Bcl-2 in a concentration and time-dependent manner. [ABSTRACT FROM AUTHOR]

To understand the mechanism of NaHSO3 as a photosynthetic accelerator on rapeseed, the effects of NaHSO3 on growth, nitrogen metabolism and photosynthetic characteristics of Brassica napus cultivar Zhuangshuang 11 were investigated in liquid solution added with NaHSO3 at the concentration of 0-0.08 mmol/L. Results showed that with 0. 02 mmolL NaHSO3, plant height increased by 21.0%, 28.4% and 40.4% respectively after 10, 15 and 20 days. Their fresh weight and root length were also increased but not significantly different to the control. With 0. 08 mmolL NaHSO3, root length was significantly decreased by 15.1 - 16.5% after 10-15 days. Contents of chlorophyll b and total chlorophyll in rapeseed seedlings significantly increased under all concentrations of NaHSO3 treatments. Increase of chlorophyll a was observed only at 0.02 mmol/L NaHSO3 treatment, and the highest contents of chlorophyll b and total chlorophyll were also achieved. After NaHSO3 treatment, photosynthetic rate (Pn), light saturation point (LCP) and apparent quantum efficiency (AQY) increased significantly, while photorespiration rate (Rp), intercellular concentration of CO2(Ci) and transpiration rate (Tr) declined significantly. With a higher maximum light energy conversion rate (Fv/Fm) and actual light energy conversion rate n) and a lower non - photochemical quenching coefficient (NPQ), the low concentration of NaHSO3 resulted in an increasing of the share of light energy which was used to describing photochemical transfer. The activity of nitrate reductase (NR) and glutamine synthetase (SR) increased after NaHSO3 treatment. In conclusion, NaHSO3 improved the photosynthesis through the increase of chlorophyll b content, which led to a higher efficiency of electronic absorption and transportation. [ABSTRACT FROM AUTHOR]

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The study presented time series of atmospheric CO2 concentrations from flask sampling at SDZ regional station in Beijing during 2007 and 2013, together with delta(13)CO2) values during 2009 and 2013. The "representative data" of CO2 and delta(13)C (CO2) were selected from the complete data for further analysis. Annual CO2 concentrations increased from 385.6 x 10(-6) in 2007 to 398.1 x 10(-6) in 2013, with an average growth rate of 2.0 x 10(-6) a(-1), while the delta(13)C values decreased from -8.38% per hundred in 2009 to -8.52% per hundred in 2013, with a mean growth rate of -0.03% per hundred x a(-1). The absolute increase of CO2 from 2007 to 2008 reached the lowest level during 2007 and 2013, possibly due to relatively less carbon emissions during the 2008 Olympic Games period. The peak-to-peak amplitudes of atmospheric CO2 and delta(13)C seasonal variations were 23. 9 x 10 -6 and 1. 03%o, respectively. The isotopic signatures of CO2 sources/sinks were also discussed in this study. The delta8 value for heating season I (Jan. 01-Mar. 14) was -21.30% per hundred, while -25.39% per hundred for heating season 11 (Nov. 15-Dec.31) , and for vegetative season (Mar. 15-Nov. 14) the delta(bio) value was estimated to be -21.28% per hundred, likely suggesting the significant impact of fossil fuel and corn straw combustions during winter heating season and biological activities during vegetative season.

To strengthen scientific management and sharing of greenhouse gas data obtained from atmospheric background stations in China, it is important to ensure the standardization of quality assurance and quality control method for background CO2 sampling and analysis. Based on the greenhouse gas sampling and observation experience of CMA, using portable sampling observation and WS-CRDS analysis technique as an example, the quality assurance measures for atmospheric CO,sampling and observation in the Waliguan station (Qinghai), the glass bottle quality assurance measures and the systematic quality control method during sample analysis, the correction method during data processing, as well as the data grading quality markers and data fitting interpolation method were systematically introduced. Finally, using this research method, the CO2 sampling and observation data at the atmospheric background stations in 3 typical regions were processed and the concentration variation characteristics were analyzed, indicating that this research method could well catch the influences of the regional and local environmental factors on the observation results, and reflect the characteristics of natural and human activities in an objective and accurate way.

The real-time, automatic, highly accurate and efficient system for measuring the mixing ratios of CO2, CH4, CO and N2O has been developed by combining the commercial FTIR system (Wollongong University) with an auto-sampling system and a working standard module. Based on the tests conducted, the FTIR showed the high precision and a relatively low accuracy associated with its poor determination of correction factors. The absolute error of the mixing ratio of CO was above 38.8 x 10(-9), suggesting that FTIR alone could not meet the requirement for the real time measurement. Using the working standard gases to adjust results from the FTIR significantly improved the accuracy of measurements. For both static and dynamic conditions, the discrepancies between the measured results and the real values were below 0.11 x 10(-6), 1.8 x 10(-9), 0.15 x 10(-9) and 0.5 x 10(-9) for CO2, CH4, N2O and CO respectively, meeting the requirements for the atmospheric real-time measurements. During 6 days in-situ measurements of greenhouse gas outside the lab, the precision of target gas can reach 0.05 x 10(-6), 0.2 x 10(-9), 0.07 x 10(-9), 0.5 x 10(-9) for CO2, CH4, N2O, CO, and inaccuracy can be 0.09 x 10(-6), 0.4 x 10(-9), 0.14 x 10(-9), 0.5 x 10(-9), respectively.

Background CH4 concentrations were continuously measured at the 4 WMO/GAW stations [Waliguan in Qinghai (WLG), Lin'an in Zhejiang (LAN), Shangdianzi in Beijing (SDZ), and Longfengshan in Heilongjiang (LFS)] by Cavity Ring Down Spectroscopy system. From 2009 to 2010, the diurnal cycle of hourly average CH4 concentration at LAN was found to be similar in all four seasons, with the highest level detected at 05:00 (Beijing Time) and the lowest at about 14:00. Similar CH4 diurnal cycles were observed at LFS in the summer time. However, the daily amplitude was much higher than that at LAN and reached 216. 8 x 10(-9) (molar ratio). For SDZ station, there were similar trends in spring, autumn and winter. The daily average concentration in the summer was much higher than those of the other seasons and reached the highest at about 20:00. No apparent CH4 diurnal cycle was observed at the WLG station during the whole year. The seasonal variations were obvious at the three regional stations (LAN, SDZ, LFS). The background concentration was the lowest in July at LAN while reached the highest level in August at LFS. The yearly background concentration variation at LFS displayed a "W" pattern. At LFS and SDZ, the wintertime CH4 concentrations were higher than those in spring and autumn. WLG represented a clean area and its CH4 value was the lowest among the four stations with the monthly average amplitude to be about 11.5 x 10(-9). At all three regional stations, non-background data accounted for more than 70% of the whole data. Cluster analysis of 3 day backward trajectories corresponding to the high CH4 concentration (WLG: CH4 > 1 870 x 10(-9), LFS: CH4 > 2100 x 10(-9), LAN: CH4 > 2 150 x10(-9), SDZ: CH4 > 2050 x 10(-9)) data points suggested that the high CH4 level measured in summer might be associated with the air mass transportation.

In-situ GC-FID system for atmospheric CH4 and CO mixing ratio measurements at the Shangdianzi (SDZ) GAW regional station in Beijing was designed and optimized in 2009 based on a comparable system at the Waliguan GAW global station in Qinhai. Results from this study indicate that the system's precisions for CH4 and CO are higher than 0.03% and 0.45% respectively, which can meet the quality target on background greenhouse gas observations by the World Meteorology Organization's Global Atmosphere Watch (WMO/GAW) program. The selection method of working standards for this system was established: two working standards (WH for the high concentration and WL for the low concentration) were selected, the concentrations of CH4 and CO in these two standards can cover the ambient mixing ratios of CH4 (2 007.1 x 10(-9) and 1 809.5 x 10(-9)) and CO (405.6 x 10(-9) and 123.8 x 10(-9)), an injection sequence was programmed so that the two standards were analyzed alternatively for every three runs. The measurement accuracies are high, as shown by the standard deviations less than 1.7 x 10(-9) and 1 x 10(-9), for CH4 and CO, respectively. This method has been applied to in-situ measurement of atmospheric CH4 and CO in North China.

To strengthen scientific management and sharing of greenhouse gas data obtained from atmospheric background stations in China, it is important to ensure the standardization of observations and establish the data treatment and quality control procedure so as to maintain consistency in atmospheric carbon dioxide (CO2) and methane (CH4) measurements from different background stations. An automated gas chromatographic system (Hewlett Packard 5890GC employing flame ionization detection) for in situ measurements of atmospheric CO2 and CH4 has been developed since 1994 at the China Global Atmosphere Watch Baseline Observatory at Mt. Waliguan, in Qinhai. In this study, processing and quality control flow of CO2 and CH4 data acquired by HP ChemStation are discussed in detail, including raw data acquisition, data merge, time series inspection, operator flag, principal investigator flag, and the comparison of the GC measurement with the flask method. Atmosphere CO2 and CH4 mixing ratios were separated as background and non-background data using a robust local regression method, approximately 72% and 44% observed values had been filtered as background data for CO2 and CH4, respectively. Comparison of the CO1 and CH, in situ data to the flask sampling data were in good agreement, the relative deviations are within +/- 0.5% for CO2 and for CH4. The data has been assimilated into global database (Globalview-CO2, Globalview-CH4), submitted to the World Data Centre for Greenhouse Gases (WDCGG), and applied to World Meteorological Organization (WMO) Greenhouse Gas Bulletin and assessment reports of the United Nations Intergovernmental Panel on Climate Change (IPCC).

Objective: To explore the mechanism of action of tanshinone II A for liver protection in hepatic fibrotic mice by observing its effects on signaling pathway of insulin-like growth factor binding protein 7 (IGFBP7) and TGFbeta1/Smad3., Methods: Hepatic fibrosis model was induced by intraperitoneal injection of thioacetamide (TAA). Thirty-six male Kunming mice were divided into five groups: the normal control group (N), the 4-week model group (A), the 4-week tanshinone II A prevented group (B), the 6-week model group (C) and the 3-week tanshinone II A treated group (D). Changes of serum levels of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH), histopathology of liver (HE staining), area density of collagen in liver (Masson staining), expressions of alpha-smooth muscle actin (alpha-SMA), collagen I , fibronectin (FN), transforming growth factor-beta1 (TGF-beta1), Smad3 and IGFBP7 in liver (by immunohiStochemistry), liver content of FN, Smad3 and IGFBP7 (by Western blot), and the hepatocyte apoptosis (by TUNEL) were observed., Results: The serum levels of ALT and LDH, the expressions of alpha-SMA, collagen I , TGF-beta1 in liver, expressions and contents of FN, Smad3 and IGFBP7 in liver were significantly lower; the liver damage and the hepatic apoptosis index were lesser in Group B than in Group A, also in Group D than in Group C, respectively, all showing statistical significance (P < 0.05)., Conclusion: Tanshinone II A could improve liver function, inhibit the activation of hepatic stellate cells, reduce the production of extracellular matrix, and protect the hepatocytes, and its of mechanisms of actions might be related with blocking TGF-beta1/Smad3 signaling pathway and down-regulating the expression of IGFBP7 in liver.

Objective: To study the correlations of mannose-binding lectin (MBL) gene promoter polymorphisms and plasma MBL concentrations to the susceptibility to HIV infection in northern Chinese Han population., Methods: This case-control study included 115 HIV-infected patients and 115 non-infected healthy individuals, in whom the MBL gene promoter polymorphisms were detected using pyrosequencing technique and plasma MBL concentrations measured using enzyme-linked immunosorbent assay (ELISA)., Results: The MBL promoter genotypes of LY/LY, LY/LX, HY/LY, HY/HY and LX/LX were detected in 66 (57.40%), 25 (21.70%), 17 (14.80%), 5 (4.30%) and 2 (1.70%) among the HIV-infected patients, and in 77 (67.00%), 23(20.00%), 12 (10.40%), 0 (0.00%), and 3 (2.60%) among the healthy individuals, respectively. The frequencies of haplotypes LY, HY and LX were 75.70%, 11.70% and 12.60% among the patients, and 82.20%, 5.20% and 12.60% among the healthy individuals, respectively, showing significant difference in the halpotype between the two groups (P=0.041). The average plasma MBL concentration was significantly lower in HIV-infected group than in the healthy individuals (1775.14-/+786.31 vs 3672.21-/+597.13 microg/L, P=0.001)., Conclusion: The genotypes of LY/LY and LY/LX and the haplotypes of LY and HY are predominant in northern Chinese Han population, and the plasma MBL concentration in HIV infected patients is generally only 50% of that in healthy individuals. We therefore presume that MBL promoter polymorphisms and plasma MBL concentration can be associated with the susceptibility to HIV infection in this population, and individuals with low plasma MBL concentration are more susceptible to HIV infection.

In order to determine the possibility of measuring the root respiration by using root exclusion method, we conducted field experiments to measured total soil respiration and net soil respiration in three temperate grassland communities including Leymus chinensis free-grazed steppe, stipa grandis free-grazed steppe and Leymus chinensis degenerated free-grazed steppe in the growing season, 2005. At the same time, the proportion of the root respiration to the total soil respiration was estimated in different steppes by this method separately. The results indicated that the root exclusion method was very operable in estimating the proportion of the root respiration to the total soil respiration in temperate grassland communities, and the proportion varied from 25% - 45% with the mean value of 35.66%. The precision of this proportion was markedly improved compared with the correlation studies of both here and abroad, and it was provided with superior applied cost in the field of carbon cycle of grassland ecosystem.

In order to determine the proportion of the root respiration to the total soil respiration, field experiments were condusted to measured soil respiration in three temperate grassland communities including Leymus chinensis free-grazed steppe, stipa grandis free-grazed steppe and Leymus chinensis degenerated free-grazed steppe using root biomass ratiocination method in the growing season, 2005. At the same time, seasonal variation including root respiration, total soil respiration and proportion of the root respiration to the total soil respiration in different grassland communities were compared, and the influence of root biomass, water and temperature to these processes were expounded. The results indicated that the rule of the root respiration and total soil respiration in the three steps was a one-peak pattern with the season dynamic, the maximum rate was in the late of July, but in Leymus chinensis degenerated free-grazed steppe, the rate was obviously larger than the other two types between July and August; The proportion of the root respiration to the total soil respiration obviously changed in the growing season, and the proportion was varied from 40% - 50 % with the mean value of 40.3 % , but it was very different among three steps because of the regional differentiations.