[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citru...[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 （25 mmol/L）, 2.0 μl of dNTP mixture （2.5 mmol/L of each dNTP）, 1.0 μl of actin gene primers （10μmol/L）, 1.0μl of 35S promoter primers （10 μmol/L）, 1.5 μl of NOS promoter primers （10 μmol/L） and 0.5 μl of NOS terminator primers （10μmol/L）, 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products.展开更多
[Objective] Abscisic acid （ABA）, a plant endogenous hormone, plays an important role in plant responses to adverse environments. This study was to explore the effects of exogenous ABA on the drought resistmlce of ap...[Objective] Abscisic acid （ABA）, a plant endogenous hormone, plays an important role in plant responses to adverse environments. This study was to explore the effects of exogenous ABA on the drought resistmlce of apple rootstocks under simulated drought condition induced by polyethylene glycol （PEG）. [Method] Apple （Malus baccata） seedlings were employed as test material. There were five treatments （T1-5） designed as ABA application rates at 0 （T1）, 25 （T2）, 50 （T3）, 75 （T4） and 100 （T5） μmol/L in the hydroponic experiments. The changes of the relative leaf water content （RLWC）, root activity, malondialdehyde （MDA） content, proline （Pro） content, superoxide dismutase （SOD） activity and peroxidase （POD） activity were assayed under PEG stress. All indices were analyzed by principal component analysis （PCA） to evaluate the optimal ABA concentration alleviating drought stress. [Result] The different concentration of ABA could increase Pro content and antioxidant enzyme activities, relieve the descent of RLWC and decrease MDA content. Low levels of ABA increased root activity, whereas the high concentrations （T3-T5） inhibited it. Statistical analysis based on the PCA indicated that the cumulative contribution rate of the first two principal components was raised to 96.457%, and the PCA in the T2 scored the highest. [Conclusion] The exogenous ABA could decrease the damage caused by drought stress to Malus baccata seedlings and enhance the ability of drought tolerance by increasing osmolyte content, anti- oxidative enzyme activity and reducing the level of membrane lipid peroxidation. The optimal concentration of ABA was 25 μmol/L.展开更多
AIM： To validate and compare the cost of microdose ^14C urea breath test （UBT） with histology and rapid urease test for the diagnosis of H Py/ori. METHODS： Ninety-four consecutive patients with dyspeptic symptoms ...AIM： To validate and compare the cost of microdose ^14C urea breath test （UBT） with histology and rapid urease test for the diagnosis of H Py/ori. METHODS： Ninety-four consecutive patients with dyspeptic symptoms undergoing gastroscopy were enrolled. Gastric biopsies were taken for histology and rapid urease test. UBT was performed after gastroscopy by microdose ^14 urea capsules. Sensitivity, specificity and accuracy of UBT were calculated and compared with histology and rapid urease test. Cost comparison of these tests was also performed. RESULTS： H pylori was diagnosed by histology and rapid urease test in 66 （70%） and 61 （65%） patients, while ^14C UBT detected infection in 63 （67%）. Accuracy of UBT was 93% in comparison with histology while its positive and negative predictive values were 97% and 84%, respectively. Comparison of ^14C UBT with rapid urease test gives an accuracy of 96%, with positive and negative predictive values of 95% and 97%, respectively. These results were highly reproducible with a Kappa test （P value 〈 0.001）. Cost of histology or rapid urease test with gastroscopy was 110 USD or 95 USD respectively while the cost of UBT was 15 USD.CONCLUSION： Microdose ^14C UBT was comparable to histology and rapid urease test. ^14C UBT is an economical, self sufficient and suitable test to diagnose active Hpylori infection in less developed countries.展开更多
Principle component analysis （PCA） based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal c...Principle component analysis （PCA） based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal com- ponent test （PCT） is non-robust and can be very sensitive to one or more outliers. In this paper, a Huber function liked robust weight factor was added in the collective chi-square test to eliminate the influence of gross errors on the PCT. Meanwhile, robust chi-square test was applied to modified simultaneous estimation of gross error （MSEGE） strategy to detect and identify multiple gross errors. Simulation results show that the proposed robust test can reduce the possibility of type Ⅱ errors effectively. Adding robust chi-square test into MSEGE does not obviously improve the power of multiple gross error identification, the proposed approach considers the influence of outliers on hypothesis statistic test and is more reasonable.展开更多
A Multi-channel Oceanographic Fluorescence Lidar(MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a(Chl-a), has been develope...A Multi-channel Oceanographic Fluorescence Lidar(MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a(Chl-a), has been developed using the Laser- induced Fluorescence(LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube(MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels(I495/I405) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer(MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water.展开更多
基金Supported by the Special Fund for Key Laboratories of Chongqing (CSTC)National Technology Research and Development Program of Ministry of Science and Technology for Countryside Field (863 Program,2011AA100205)+1 种基金Special Fund for Agro-scientific Research in the Public Interest of Ministry of Agriculture of China(201003067)Key Science and Technology Research Program of Ministry of Education of China (109131)~~
文摘[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 （25 mmol/L）, 2.0 μl of dNTP mixture （2.5 mmol/L of each dNTP）, 1.0 μl of actin gene primers （10μmol/L）, 1.0μl of 35S promoter primers （10 μmol/L）, 1.5 μl of NOS promoter primers （10 μmol/L） and 0.5 μl of NOS terminator primers （10μmol/L）, 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products.
文摘[Objective] Abscisic acid （ABA）, a plant endogenous hormone, plays an important role in plant responses to adverse environments. This study was to explore the effects of exogenous ABA on the drought resistmlce of apple rootstocks under simulated drought condition induced by polyethylene glycol （PEG）. [Method] Apple （Malus baccata） seedlings were employed as test material. There were five treatments （T1-5） designed as ABA application rates at 0 （T1）, 25 （T2）, 50 （T3）, 75 （T4） and 100 （T5） μmol/L in the hydroponic experiments. The changes of the relative leaf water content （RLWC）, root activity, malondialdehyde （MDA） content, proline （Pro） content, superoxide dismutase （SOD） activity and peroxidase （POD） activity were assayed under PEG stress. All indices were analyzed by principal component analysis （PCA） to evaluate the optimal ABA concentration alleviating drought stress. [Result] The different concentration of ABA could increase Pro content and antioxidant enzyme activities, relieve the descent of RLWC and decrease MDA content. Low levels of ABA increased root activity, whereas the high concentrations （T3-T5） inhibited it. Statistical analysis based on the PCA indicated that the cumulative contribution rate of the first two principal components was raised to 96.457%, and the PCA in the T2 scored the highest. [Conclusion] The exogenous ABA could decrease the damage caused by drought stress to Malus baccata seedlings and enhance the ability of drought tolerance by increasing osmolyte content, anti- oxidative enzyme activity and reducing the level of membrane lipid peroxidation. The optimal concentration of ABA was 25 μmol/L.
基金University Research Council Grant, No. 041F431YC
文摘AIM： To validate and compare the cost of microdose ^14C urea breath test （UBT） with histology and rapid urease test for the diagnosis of H Py/ori. METHODS： Ninety-four consecutive patients with dyspeptic symptoms undergoing gastroscopy were enrolled. Gastric biopsies were taken for histology and rapid urease test. UBT was performed after gastroscopy by microdose ^14 urea capsules. Sensitivity, specificity and accuracy of UBT were calculated and compared with histology and rapid urease test. Cost comparison of these tests was also performed. RESULTS： H pylori was diagnosed by histology and rapid urease test in 66 （70%） and 61 （65%） patients, while ^14C UBT detected infection in 63 （67%）. Accuracy of UBT was 93% in comparison with histology while its positive and negative predictive values were 97% and 84%, respectively. Comparison of ^14C UBT with rapid urease test gives an accuracy of 96%, with positive and negative predictive values of 95% and 97%, respectively. These results were highly reproducible with a Kappa test （P value 〈 0.001）. Cost of histology or rapid urease test with gastroscopy was 110 USD or 95 USD respectively while the cost of UBT was 15 USD.CONCLUSION： Microdose ^14C UBT was comparable to histology and rapid urease test. ^14C UBT is an economical, self sufficient and suitable test to diagnose active Hpylori infection in less developed countries.
基金The National Natural Science Foundation of China(No 60504033)
文摘Principle component analysis （PCA） based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal com- ponent test （PCT） is non-robust and can be very sensitive to one or more outliers. In this paper, a Huber function liked robust weight factor was added in the collective chi-square test to eliminate the influence of gross errors on the PCT. Meanwhile, robust chi-square test was applied to modified simultaneous estimation of gross error （MSEGE） strategy to detect and identify multiple gross errors. Simulation results show that the proposed robust test can reduce the possibility of type Ⅱ errors effectively. Adding robust chi-square test into MSEGE does not obviously improve the power of multiple gross error identification, the proposed approach considers the influence of outliers on hypothesis statistic test and is more reasonable.
基金supported by the National High Technology Research and Development Program (2006AA06Z415)the Global Change Research Program of China (2012CB955603)
文摘A Multi-channel Oceanographic Fluorescence Lidar(MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a(Chl-a), has been developed using the Laser- induced Fluorescence(LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube(MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels(I495/I405) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer(MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water.
