Brassica chinensis L. were foliarly applied with glycinebetaine (GB), as this species is unable to synthesis GB and sensitive to osmotic stress such as salt. The exogenous GB was easily absorbed and transported by t...Brassica chinensis L. were foliarly applied with glycinebetaine (GB), as this species is unable to synthesis GB and sensitive to osmotic stress such as salt. The exogenous GB was easily absorbed and transported by the leaf of B. chinensis . Its application (0-20 mmol/L) enhanced the plant tolerance to salt stress. The treatment of 15 mmol/L GB significantly decreased the Na + accumulation in leaf and root under NaCl stress. This difference in accumulating Na + and K + is caused by higher selectivity of root absorption. Furthermore, GB increased H +_ATPase activity of root plasma membrane evidently. This result strongly suggested that in root the decreased Na + accumulation was caused by the GB accumulation that enhanced the extrusion of Na + from the cell in some way through plasma membrane transporter, e.g. Na +/H + antiport driven by H +_ATPase. The GB application was also found to stabilize the plasma membrane, to decrease the loss of chlorophyll, and to stimulate the osmosis induced proline response under salt stress.展开更多
The Late Paleozoic layered or stratoid-layered basalts in western Guangxi have similar elemental and isotopic compositions to Emeishan high-Ti basalts. Whole-rock ^40Ar/^39Ar and SHRIMP zircon U-Pb dating were carried...The Late Paleozoic layered or stratoid-layered basalts in western Guangxi have similar elemental and isotopic compositions to Emeishan high-Ti basalts. Whole-rock ^40Ar/^39Ar and SHRIMP zircon U-Pb dating were carried out for the representative basalt samples in three typical profiles in the area. Three basalts from the upper segment of Yangxu profile and lower segment of Yufeng and Min'an profiles yield the 4^40Ar/^39Ar plateau ages of 253.6±0.4 Ma (20BS-71),255.4±0.4 Ma (20BS-99) and 256.2±0.8 Ma (20BS-119), respectively. Twenty-three analyses on 23 zircons of the basalt from the upper segment of Yangxu profile give a weighted mean ^206Pb/^238U age of 253.7±6.1 Ma with an MSWD=2.8.These new and published geochronological data for Emeishan large igneous province (LIP) indicate that the Emeishan LIP was initiated at -260 Ma, voluminously erupted between 253 and 256 Ma, and possibly ended at -251-253Ma: The age (251-260Ma) is generally consistent with that of the associated environmental deterioration and mass extinction events at the end-Guadalupian and Permo-Triassic boundary. These precise geochronological data provide important constraints on the dominantly eruptive time of the Emeishan LIP and understanding of the distribution of Emeishan high-Ti basalts and its mantle plume dynamics.展开更多
AIM： To evaluate the antibacterial activity of Sapindus mukorossi （S. mukorossl） and Rheum emodi （R. emodl）. METHODS： Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzen...AIM： To evaluate the antibacterial activity of Sapindus mukorossi （S. mukorossl） and Rheum emodi （R. emodl）. METHODS： Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylon, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram ＋ve （S. aureus, B. subtilis） and two Gram -ve （E. coli, P. vugaris） organisms were screened for their susceptibility patterns against these extracts. RESULTS： In our screening, all 30 resistant isolates and the other four organisms （two Gram ＋ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris） were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited Hpylori at very low concentrations, In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations （10 μg/mL） for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi （2.5 mg/mL） and R. emodi （3.0 mg/mL） given orally for seven days. CONCLUSION： We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.展开更多
在2003年制定的H.264/AVC视频编码标准获得巨大的成功后,新一代视频编码国际标准HEVC(High Ef-ficiency Video Coding)在ITU-T的VCEG和ISO/IEC的MPEG通力合作下已经开发成功。HEVC提供了多项先进的视频编码技术。尽管HEVC的视频编码层...在2003年制定的H.264/AVC视频编码标准获得巨大的成功后,新一代视频编码国际标准HEVC(High Ef-ficiency Video Coding)在ITU-T的VCEG和ISO/IEC的MPEG通力合作下已经开发成功。HEVC提供了多项先进的视频编码技术。尽管HEVC的视频编码层结构仍然是常见的基于块运动补偿的混合视频编码模式,但是和先前的标准相比具有多处重要改进。文中对HEVC标准的技术的主要特点和性能进行了综述。展开更多
AIM: To examine the effects of Helicobacter pylori(Hpylori) infection on the invasiveness of gastric cancer cells,and to elucidate its mechanism. METHODS: Gastric carcinoma cells, MKN-45, were incubated with CagA-posi...AIM: To examine the effects of Helicobacter pylori(Hpylori) infection on the invasiveness of gastric cancer cells,and to elucidate its mechanism. METHODS: Gastric carcinoma cells, MKN-45, were incubated with CagA-positive H pylori, and cell invasion was determined by Matrigel analysis.The expression of matrix metallopr-oteinase-9 (MMP-9),vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) were assessed by Western-blot analysis, and transcriptional activation of the COX-2 promoter was examined by measuring luciferase and β-galactosidase activities. Lastly,the proteinDNA interaction was confirmed by an electrophoretic mobility shift assay. RESULTS: The current studies showed that: (1) incubation of CagA-positive H pylori with MKN-45 cells significantly promotes gastric cancer cells invasion, and this effect is attenuated by pre-treatment with NS-398, a COX-2 inhibitor, or PDTC,a nuclear factor κB (NF-κB) inhibitor;(2) the induction of MKN-45 cells invasion by Hpylori is associated with increases in COX-2, MMP-9, and VEGF protein expression, and co-incubation of NS-398 or PDTC significantly reduces these effects;(3) H pylori infection transactivates COX-2 promoter activity and increases the binding of NF-κB to this promoter. CONCLUSION: Our data demonstrate that H pylori infection promotes gastric epithelial cells invasion by activating MMP-9 and VEGF expression. These effects appear to be mediated through a NF-κB and COX-2 mediated pathway, as COX-2 or NF-κB inhibitor significantly attenuate the invasiveness of gastric cancer cells and the expressions of MMP-9 and VEGF protein.展开更多
This article investigates gain self-scheduled H 1 robust control system design for a tailless fold- ing-wing morphing aircraft in the wing shape varying process. During the wing morphing phase, the aircraft＇s dynamic...This article investigates gain self-scheduled H 1 robust control system design for a tailless fold- ing-wing morphing aircraft in the wing shape varying process. During the wing morphing phase, the aircraft＇s dynamic response will be governed by time-varying aerodynamic forces and moments. Nonlinear dynamic equations of the morphing aircraft are linearized by using Jacobian linearization approach, and a linear parameter varying （LPV） model of the morphing aircraft in wing folding is obtained. A multi-loop controller for the morphing aircraft is formulated to guarantee stability for the wing shape transition process. The proposed controller uses a set of inner-loop gains to provide stability using classical techniques, whereas a gain self-scheduled H 1 outer-loop controller is devised to guarantee a specific level of robust stability and performance for the time-varying dynamics. The closed-loop simulations show that speed and altitude vary slightly during the whole wing folding process, and they converge rapidly after the process ends. This proves that the gain self-scheduled H 1 robust controller can guarantee a satisfactory dynamic performance for the morphing aircraft during the whole wing shape transition process. Finally, the flight control system＇s robustness for the wing folding process is verified according to uncertainties of the aerodynamic parameters in the nonlinear model.展开更多
Infection with H pylori leads to a persistent chronic inflammation of the gastric mucosa, thereby increasing the risk of distal gastric adenocarcinoma. Numerous studies have determined a clear correlation between Hpyl...Infection with H pylori leads to a persistent chronic inflammation of the gastric mucosa, thereby increasing the risk of distal gastric adenocarcinoma. Numerous studies have determined a clear correlation between Hpylori infection and the risk of gastric cancer; however, general eradication is not recommended as cancer prophylaxis and time points for treatment remain controversial in different areas of the world. Prevalence rates in Western countries are decreasing, especially in younger people （〈 10%）; and a decline in distal gastric adenocarcinoma has been observed. Risk groups in Western countries still show considerably higher risk of developing cancer, especially in patients infected with cagA^＋ strains and in persons harboring genetic polymorphism of the IL-1B promoter （-511T/T） and the corresponding IL-1 receptor antagonist （IL-1RN^＊2）. Thus, general eradication of all infected persons in Western countries not recommended and is limited to risk groups in order to achieve a risk reduction. In contrast, infection rates and cancer prevalence are still high in East Asian countries. A prevention strategy to treat infected persons may avoid the development of gastric cancer to a large extent and with enormous clinical importance. However, studies in China and Japan indicate that prevention of gastric cancer is effective only in those patients that do not display severe histological changes such as atrophy and intestinal metaplasia. Thus, prophylactic strategies to prevent gastric cancer in high risk populations such as China should therefore especially aim at individuals now at younger age when the histological alterations caused by the bacterial infection was still reversible. In countries with a low prevalence of gastric cancer, risk groups carrying cagA^＋ strains and IL-1 genetic polymorphisms should be identified and treated.展开更多
文摘Brassica chinensis L. were foliarly applied with glycinebetaine (GB), as this species is unable to synthesis GB and sensitive to osmotic stress such as salt. The exogenous GB was easily absorbed and transported by the leaf of B. chinensis . Its application (0-20 mmol/L) enhanced the plant tolerance to salt stress. The treatment of 15 mmol/L GB significantly decreased the Na + accumulation in leaf and root under NaCl stress. This difference in accumulating Na + and K + is caused by higher selectivity of root absorption. Furthermore, GB increased H +_ATPase activity of root plasma membrane evidently. This result strongly suggested that in root the decreased Na + accumulation was caused by the GB accumulation that enhanced the extrusion of Na + from the cell in some way through plasma membrane transporter, e.g. Na +/H + antiport driven by H +_ATPase. The GB application was also found to stabilize the plasma membrane, to decrease the loss of chlorophyll, and to stimulate the osmosis induced proline response under salt stress.
文摘The Late Paleozoic layered or stratoid-layered basalts in western Guangxi have similar elemental and isotopic compositions to Emeishan high-Ti basalts. Whole-rock ^40Ar/^39Ar and SHRIMP zircon U-Pb dating were carried out for the representative basalt samples in three typical profiles in the area. Three basalts from the upper segment of Yangxu profile and lower segment of Yufeng and Min'an profiles yield the 4^40Ar/^39Ar plateau ages of 253.6±0.4 Ma (20BS-71),255.4±0.4 Ma (20BS-99) and 256.2±0.8 Ma (20BS-119), respectively. Twenty-three analyses on 23 zircons of the basalt from the upper segment of Yangxu profile give a weighted mean ^206Pb/^238U age of 253.7±6.1 Ma with an MSWD=2.8.These new and published geochronological data for Emeishan large igneous province (LIP) indicate that the Emeishan LIP was initiated at -260 Ma, voluminously erupted between 253 and 256 Ma, and possibly ended at -251-253Ma: The age (251-260Ma) is generally consistent with that of the associated environmental deterioration and mass extinction events at the end-Guadalupian and Permo-Triassic boundary. These precise geochronological data provide important constraints on the dominantly eruptive time of the Emeishan LIP and understanding of the distribution of Emeishan high-Ti basalts and its mantle plume dynamics.
文摘AIM： To evaluate the antibacterial activity of Sapindus mukorossi （S. mukorossl） and Rheum emodi （R. emodl）. METHODS： Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylon, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram ＋ve （S. aureus, B. subtilis） and two Gram -ve （E. coli, P. vugaris） organisms were screened for their susceptibility patterns against these extracts. RESULTS： In our screening, all 30 resistant isolates and the other four organisms （two Gram ＋ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris） were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited Hpylori at very low concentrations, In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations （10 μg/mL） for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi （2.5 mg/mL） and R. emodi （3.0 mg/mL） given orally for seven days. CONCLUSION： We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.
文摘在2003年制定的H.264/AVC视频编码标准获得巨大的成功后,新一代视频编码国际标准HEVC(High Ef-ficiency Video Coding)在ITU-T的VCEG和ISO/IEC的MPEG通力合作下已经开发成功。HEVC提供了多项先进的视频编码技术。尽管HEVC的视频编码层结构仍然是常见的基于块运动补偿的混合视频编码模式,但是和先前的标准相比具有多处重要改进。文中对HEVC标准的技术的主要特点和性能进行了综述。
基金Supported by the Taichung Veterans General Hospital Research Grant: TCVGH-933308C
文摘AIM: To examine the effects of Helicobacter pylori(Hpylori) infection on the invasiveness of gastric cancer cells,and to elucidate its mechanism. METHODS: Gastric carcinoma cells, MKN-45, were incubated with CagA-positive H pylori, and cell invasion was determined by Matrigel analysis.The expression of matrix metallopr-oteinase-9 (MMP-9),vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) were assessed by Western-blot analysis, and transcriptional activation of the COX-2 promoter was examined by measuring luciferase and β-galactosidase activities. Lastly,the proteinDNA interaction was confirmed by an electrophoretic mobility shift assay. RESULTS: The current studies showed that: (1) incubation of CagA-positive H pylori with MKN-45 cells significantly promotes gastric cancer cells invasion, and this effect is attenuated by pre-treatment with NS-398, a COX-2 inhibitor, or PDTC,a nuclear factor κB (NF-κB) inhibitor;(2) the induction of MKN-45 cells invasion by Hpylori is associated with increases in COX-2, MMP-9, and VEGF protein expression, and co-incubation of NS-398 or PDTC significantly reduces these effects;(3) H pylori infection transactivates COX-2 promoter activity and increases the binding of NF-κB to this promoter. CONCLUSION: Our data demonstrate that H pylori infection promotes gastric epithelial cells invasion by activating MMP-9 and VEGF expression. These effects appear to be mediated through a NF-κB and COX-2 mediated pathway, as COX-2 or NF-κB inhibitor significantly attenuate the invasiveness of gastric cancer cells and the expressions of MMP-9 and VEGF protein.
基金co-supported by China Postdoctoral Science Foundation(Nos.20110490259,2012T50038)
文摘This article investigates gain self-scheduled H 1 robust control system design for a tailless fold- ing-wing morphing aircraft in the wing shape varying process. During the wing morphing phase, the aircraft＇s dynamic response will be governed by time-varying aerodynamic forces and moments. Nonlinear dynamic equations of the morphing aircraft are linearized by using Jacobian linearization approach, and a linear parameter varying （LPV） model of the morphing aircraft in wing folding is obtained. A multi-loop controller for the morphing aircraft is formulated to guarantee stability for the wing shape transition process. The proposed controller uses a set of inner-loop gains to provide stability using classical techniques, whereas a gain self-scheduled H 1 outer-loop controller is devised to guarantee a specific level of robust stability and performance for the time-varying dynamics. The closed-loop simulations show that speed and altitude vary slightly during the whole wing folding process, and they converge rapidly after the process ends. This proves that the gain self-scheduled H 1 robust controller can guarantee a satisfactory dynamic performance for the morphing aircraft during the whole wing shape transition process. Finally, the flight control system＇s robustness for the wing folding process is verified according to uncertainties of the aerodynamic parameters in the nonlinear model.
基金Supported by Deutsche Forschungsgemeinschaft (DFGGraduiertenkolleg 333: Biology of Human Diseases) and by agrant from the DFG to C.P. (Pr 411/9-1) and the Dr. Else Kr nerFresenius Stiftung
文摘Infection with H pylori leads to a persistent chronic inflammation of the gastric mucosa, thereby increasing the risk of distal gastric adenocarcinoma. Numerous studies have determined a clear correlation between Hpylori infection and the risk of gastric cancer; however, general eradication is not recommended as cancer prophylaxis and time points for treatment remain controversial in different areas of the world. Prevalence rates in Western countries are decreasing, especially in younger people （〈 10%）; and a decline in distal gastric adenocarcinoma has been observed. Risk groups in Western countries still show considerably higher risk of developing cancer, especially in patients infected with cagA^＋ strains and in persons harboring genetic polymorphism of the IL-1B promoter （-511T/T） and the corresponding IL-1 receptor antagonist （IL-1RN^＊2）. Thus, general eradication of all infected persons in Western countries not recommended and is limited to risk groups in order to achieve a risk reduction. In contrast, infection rates and cancer prevalence are still high in East Asian countries. A prevention strategy to treat infected persons may avoid the development of gastric cancer to a large extent and with enormous clinical importance. However, studies in China and Japan indicate that prevention of gastric cancer is effective only in those patients that do not display severe histological changes such as atrophy and intestinal metaplasia. Thus, prophylactic strategies to prevent gastric cancer in high risk populations such as China should therefore especially aim at individuals now at younger age when the histological alterations caused by the bacterial infection was still reversible. In countries with a low prevalence of gastric cancer, risk groups carrying cagA^＋ strains and IL-1 genetic polymorphisms should be identified and treated.
