Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geom...Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 m.Soil samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility attributes.All plots were classified into geomorphological units.Analyses of variance and linear regressions were applied to all terrain,soil fertility and tree growth attributes.Important Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the experiment.This explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in valleys.However,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent waterways.The results showed that soil fertility is mainly influenced by topography.Monte-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil fertility.Furthermore,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to leaching.This geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm depth.Few soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor roles.Nevertheless,soil acidity and a high proportion of Al on the exchange complex affe展开更多
Aims Growth rates of plants are driven by factors that influence the amount of resources captured and the efficiency of resource use.In trees,the amount of light captured and the efficiency of light use strongly depen...Aims Growth rates of plants are driven by factors that influence the amount of resources captured and the efficiency of resource use.In trees,the amount of light captured and the efficiency of light use strongly depends on crown characteristics and leaf traits.Although theory predicts that both crown and leaf traits affect tree growth,few studies have yet to integrate these two types of traits to explain species-specific growth rates.Using 37 broad-leaved tree species of subtropical forests in SE China,we investigated how interspecific differences in wood volume growth rates were affected by crown and leaf traits.We tested the hypotheses that(i)larger crown dimensions promote growth rates,(ii)species-specific growth rates are positively related to leaf stomatal conductance,leaf water potential and leaf chemical components,and negatively related to leaf C/N and leaf toughness and(iii)the two sets of traits better explain growth rates in combination than either alone.Methods Our study was conducted in a large-scale forest Biodiversity and Ecosystem Functioning experiment in China(BEF-China),located in a mountainous region in Jiangxi Province.We related 17 functional traits(two crown dimension and three crown structure traits;six physiological and six morphological leaf traits)to the mean annual growth rate of wood volume of young trees of the studied species.Interrelationships between crown and leaf traits were analyzed using principal component analysis.Simple linear regression analysis was used to test the effect of each trait separately.We used multiple regression analysis to establish the relationship of growth rate to each set of traits(crown traits,physiological and morphological leaf traits)and to the combination of all types of traits.The coefficients of determination(R^(2)_(adj))of the best multiple regression models were compared to determine the relative explanatory power of crown and leaf traits and a combination of both.Important Findings The species-specific growth rates were not related to any of the展开更多
Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our o...Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our objective was to assess the role of resource partitioning and species interactions as two important mechanisms that can bring about CEs by interspecific and intraspecific trait variation.Methods We measured tree height of 2493 living individuals in 57 plots and specific root length(SRL)on first-order roots of 368 of these individuals across different species richness levels(1,2,4,8 species)in a large-scale forest biodiversity and ecosystem functioning experiment in subtropical China(BEF-China)established in 2009.We describe the effects of resource partitioning between species by a fixed component of interspecific functional diversity(RaoQ)and further effects of species interactions by variable components of interspecific and intraspecific functional diversity(community weighted trait similarity and trait dissimilarity,CWS and CWD).Finally,we examined the relationships between biodiversity effects on stand-level tree height and functional diversity(RaoQ,CWS and CWD)in SRL using linear regression and assessed the relative importance of these three components of functional diversity in explaining the diversity effects.Important Findings Our results show that species richness significantly affected SRL in five and tree height in ten out of 16 species.A positive NE was generally brought about by a positive CE on stand-level tree height and related to high values of RaoQ and CWS in SRL.A positive CE was related to high values of all three components of root functional diversity(RaoQ,CWS and CWD).Our study suggests that both resource partitioning and species interactions are the underlying mechanisms of biodiversity effects on stand-level tree growth in subtropical forest.展开更多
AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fl...AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fluorouracil (5-FU), folinic acid (FA) and oxaliplatin (FOLFOX) 6 (arm A, n = 74) or 5-FU, FA and irinotecan (FOLFIRI) (arm B, n = 77). KRAS mutation status was determined retrospectively in a subset of tumors (n = 117). RESULTS: No significant difference was found between treatment arms A and B in the progression-free survival (PFS) rate at 9 mo, 45% vs 34%; median PFS, 8.6 mo vs 8.3 mo [hazard ratio (HR) = 1.06]; overall response rate (ORR) 43% vs 45% [odds ratio (OR) = 0.93] and median overall survival (OS), 17.4 mo vs 18.9 mo (HR = 0.98). Patients with KRAS wild-type tumors demonstrated improved PFS (HR = 0.55, P = 0.0051), OS, (HR = 0.62, P = 0.0296) and ORR (53% vs 36%) and in arm A, improved PFS (HR = 0.49, P = 0.0196), OS (HR = 0.48, P = 0.0201) and ORR (56%vs 30%), compared with patients with KRAS mutated tumors. In arm B no significant differences were found in efficacy by KRAS mutation status. Treatment in arms A and B was generally well tolerated. CONCLUSION: This study confirms that combinations of cetuximab with FOLFOX6 or FOLFIRI are effective and significantly improve clinical outcome in KRAS wild-type compared with KRAS mutated mCRC.展开更多
AIM:To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography(CT)in a prospective study.METHODS:Ten patients with suspected pancreatic tumors were examined prospe...AIM:To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography(CT)in a prospective study.METHODS:Ten patients with suspected pancreatic tumors were examined prospectively using multidetec-tor CT(Somatom Sensation 16,Siemens,Erlangen,Germany).The images were evaluated for the pres-ence of a pancreatic carcinoma and invasion of the peripancreatic vessels and surrounding organs.Using the isotropic CT data sets,a three-dimensional image was created with automatic vascular analysis and semi-automatic segmentation of the organs and pancreatic tumor by a radiologist.The CT examinations and the three-dimensional images were presented to the sur-geon directly before and during the patient's operation using the Medical Imaging Interaction Toolkit-based software "ReLiver".Immediately after surgery,the value of the two images was judged by the surgeon.The operation and the histological results served as the gold standard.RESULTS:Nine patients had a pancreatic carcinoma(all pT3),and one patient had a serous cystadenoma.One tumor inf iltrated the superior mesenteric vein.The inf iltration was correctly evaluated.All carcinomas were resectable.In comparison to the CT image with axial and coronal reconstructions,the three-dimensional image was judged by the surgeons as better for operation planning and consistently described as useful.CONCLUSION:A 3D-image of the pancreas repre-sents an invaluable aid to the surgeon.However,the 3D-software must be further developed in order to be integrated into daily clinical routine.展开更多
The China Seismo-Electromagnetic Satellite(CSES) is the first platform of China's earthquake observation system in space and the first satellite of China's geophysical field detection missions. The high precis...The China Seismo-Electromagnetic Satellite(CSES) is the first platform of China's earthquake observation system in space and the first satellite of China's geophysical field detection missions. The high precision magnetometer(HPM), which contains two fluxgate sensors and a coupled dark state magnetometer(CDSM), measures the vector of the Earth's magnetic field with a bandwidth from DC to 15 Hz. The two fluxgate sensors are in a gradiometer configuration in order to reduce satellite interferences. Additionally, the CDSM sensor measures the scalar value of the magnetic field with higher accuracy and stability.Several data processing and calibration methods have been prepared to get accurate vector magnetic field data. This includes the calibration of each of the three sensors, the absolute vector correction algorithm, the spacecraft magnetic interference elimination and the coordinate transformation method. Also the instrument performances based on ground calibration activities are shown in this article.展开更多
Water quality of the river Nile and trace elements of the water, sediments and fish tissues were investigated in the current work. Eighteen different sampling points were selected along the whole course of the River N...Water quality of the river Nile and trace elements of the water, sediments and fish tissues were investigated in the current work. Eighteen different sampling points were selected along the whole course of the River Nile from its spring at Aswan to its estuaries at Rosetta and Damietta. Higher mean value of conductivity, alkalinity, chemical oxygen demand (COD), total organic carbon (TOC), ammonia (NH3), nitrate (NO3), total solid (TS), sulphate (SO4), chloride (Cl), orthophosphate were recorded in the water of Damietta and Rosetta branches comparing to other sites. Also trace metals in the water, sediments and tissues of Clarias gariepinus increased significantly (P Fe > Cu > Pb > Mn > Cr> Cd > Hg. In the gill tissues theses metals were accumulated in the following order Fe > Zn > Mn > Pb > Cr > Cu > Cd> Hg. The low accumulation of metals in muscle may be due to lack of binding affinity of these metals with the proteins of muscle. This is particularly important because muscles contribute the greatest mass of the flesh that is consumed as food.展开更多
AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on the differentiation of colonic lamina propria fibroblasts (CLPF) into myofibroblasts in vitro.METHODS: Primary CLPF cultures were in...AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on the differentiation of colonic lamina propria fibroblasts (CLPF) into myofibroblasts in vitro.METHODS: Primary CLPF cultures were incubated with TGF-β1 and analyzed for production of m-smooth muscle actin (α-SMA), fibronectin (FN) and FN isoforms. Migration assays were performed in a modified 48-well Boyden chamber. Levels of total and phosphorylated focal adhesion kinase (FAK) in CLPF were analyzed after induction of migration.did not change α-SMA levels, while TGF-β1 treatment for 6 d significantly increased α-SIVlA production. Short term incubation (6 h) with TGF-β1 enhanced CLPF migration, while long term treatment (6 d) of CLPF with TGF-β1 reduced migration to 15%-37% compared to untreated cells. FN and FN isoform mRNA expression were increased after short term incubation with TGF-β1 (2 d) in contrast to long term incubation with TGF-β1 for 6 d. After induction of migration, TGF-β1-preincubated CLPF showed higher amounts of FN and its isoforms and lower levels of total and phosphorylated FAK than untreated cells.CONCLUSION: Long term incubation of CLPF with TGF-β1 induced differentiation into myofibroblasts with enhanced α-SMA, reduced migratory potential and FAK phosphorylation, and increased FN production. In contrast, short term contact (6 h) of fibroblasts with TGF-β1 induced a dose-dependent increase of cell migration and FAK phosphorylation without induction of α-SMA production.展开更多
基金funded by the German Research Foundation(DFG FOR 891/1,2 and 3)funds from the National Natural Science Foundation of China(NSFC 30710103907,30930005,31170457 and 31210103910)+2 种基金the Swiss National Science Foundation(SNSF)financed by the Sino-German Centre for Research Promotion in Beijing(GZ 524,592,698,699 and 785)the University of Tübingen,Germany(PROMOS).
文摘Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 m.Soil samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility attributes.All plots were classified into geomorphological units.Analyses of variance and linear regressions were applied to all terrain,soil fertility and tree growth attributes.Important Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the experiment.This explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in valleys.However,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent waterways.The results showed that soil fertility is mainly influenced by topography.Monte-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil fertility.Furthermore,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to leaching.This geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm depth.Few soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor roles.Nevertheless,soil acidity and a high proportion of Al on the exchange complex affe
基金the entire BEF-China research group for their supportfunded by the German Research Foundation(DFG FOR 891/1,2 and 3)financed by the Sino-German Centre for Research Promotion in Beijing(GZ 524,592,698,699 and 785).
文摘Aims Growth rates of plants are driven by factors that influence the amount of resources captured and the efficiency of resource use.In trees,the amount of light captured and the efficiency of light use strongly depends on crown characteristics and leaf traits.Although theory predicts that both crown and leaf traits affect tree growth,few studies have yet to integrate these two types of traits to explain species-specific growth rates.Using 37 broad-leaved tree species of subtropical forests in SE China,we investigated how interspecific differences in wood volume growth rates were affected by crown and leaf traits.We tested the hypotheses that(i)larger crown dimensions promote growth rates,(ii)species-specific growth rates are positively related to leaf stomatal conductance,leaf water potential and leaf chemical components,and negatively related to leaf C/N and leaf toughness and(iii)the two sets of traits better explain growth rates in combination than either alone.Methods Our study was conducted in a large-scale forest Biodiversity and Ecosystem Functioning experiment in China(BEF-China),located in a mountainous region in Jiangxi Province.We related 17 functional traits(two crown dimension and three crown structure traits;six physiological and six morphological leaf traits)to the mean annual growth rate of wood volume of young trees of the studied species.Interrelationships between crown and leaf traits were analyzed using principal component analysis.Simple linear regression analysis was used to test the effect of each trait separately.We used multiple regression analysis to establish the relationship of growth rate to each set of traits(crown traits,physiological and morphological leaf traits)and to the combination of all types of traits.The coefficients of determination(R^(2)_(adj))of the best multiple regression models were compared to determine the relative explanatory power of crown and leaf traits and a combination of both.Important Findings The species-specific growth rates were not related to any of the
基金funded by the National Natural Science Foundation of China(No.31300353)China Postdoctoral Science Foundation(No.2014M561089)+4 种基金Science and Technology Planning Project of Jiangxi Provincial Education Department(No.GJJ150384)the entire BEF-China research group for their supportfunded by the German Research Foundation(DFG FOR891)National Natural Science Foundation of China(NSFC)the Swiss National Science Foundation(SNSF).
文摘Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our objective was to assess the role of resource partitioning and species interactions as two important mechanisms that can bring about CEs by interspecific and intraspecific trait variation.Methods We measured tree height of 2493 living individuals in 57 plots and specific root length(SRL)on first-order roots of 368 of these individuals across different species richness levels(1,2,4,8 species)in a large-scale forest biodiversity and ecosystem functioning experiment in subtropical China(BEF-China)established in 2009.We describe the effects of resource partitioning between species by a fixed component of interspecific functional diversity(RaoQ)and further effects of species interactions by variable components of interspecific and intraspecific functional diversity(community weighted trait similarity and trait dissimilarity,CWS and CWD).Finally,we examined the relationships between biodiversity effects on stand-level tree height and functional diversity(RaoQ,CWS and CWD)in SRL using linear regression and assessed the relative importance of these three components of functional diversity in explaining the diversity effects.Important Findings Our results show that species richness significantly affected SRL in five and tree height in ten out of 16 species.A positive NE was generally brought about by a positive CE on stand-level tree height and related to high values of RaoQ and CWS in SRL.A positive CE was related to high values of all three components of root functional diversity(RaoQ,CWS and CWD).Our study suggests that both resource partitioning and species interactions are the underlying mechanisms of biodiversity effects on stand-level tree growth in subtropical forest.
文摘AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fluorouracil (5-FU), folinic acid (FA) and oxaliplatin (FOLFOX) 6 (arm A, n = 74) or 5-FU, FA and irinotecan (FOLFIRI) (arm B, n = 77). KRAS mutation status was determined retrospectively in a subset of tumors (n = 117). RESULTS: No significant difference was found between treatment arms A and B in the progression-free survival (PFS) rate at 9 mo, 45% vs 34%; median PFS, 8.6 mo vs 8.3 mo [hazard ratio (HR) = 1.06]; overall response rate (ORR) 43% vs 45% [odds ratio (OR) = 0.93] and median overall survival (OS), 17.4 mo vs 18.9 mo (HR = 0.98). Patients with KRAS wild-type tumors demonstrated improved PFS (HR = 0.55, P = 0.0051), OS, (HR = 0.62, P = 0.0296) and ORR (53% vs 36%) and in arm A, improved PFS (HR = 0.49, P = 0.0196), OS (HR = 0.48, P = 0.0201) and ORR (56%vs 30%), compared with patients with KRAS mutated tumors. In arm B no significant differences were found in efficacy by KRAS mutation status. Treatment in arms A and B was generally well tolerated. CONCLUSION: This study confirms that combinations of cetuximab with FOLFOX6 or FOLFIRI are effective and significantly improve clinical outcome in KRAS wild-type compared with KRAS mutated mCRC.
文摘AIM:To evaluate the use of three-dimensional imaging of pancreatic carcinoma using multidetector computed tomography(CT)in a prospective study.METHODS:Ten patients with suspected pancreatic tumors were examined prospectively using multidetec-tor CT(Somatom Sensation 16,Siemens,Erlangen,Germany).The images were evaluated for the pres-ence of a pancreatic carcinoma and invasion of the peripancreatic vessels and surrounding organs.Using the isotropic CT data sets,a three-dimensional image was created with automatic vascular analysis and semi-automatic segmentation of the organs and pancreatic tumor by a radiologist.The CT examinations and the three-dimensional images were presented to the sur-geon directly before and during the patient's operation using the Medical Imaging Interaction Toolkit-based software "ReLiver".Immediately after surgery,the value of the two images was judged by the surgeon.The operation and the histological results served as the gold standard.RESULTS:Nine patients had a pancreatic carcinoma(all pT3),and one patient had a serous cystadenoma.One tumor inf iltrated the superior mesenteric vein.The inf iltration was correctly evaluated.All carcinomas were resectable.In comparison to the CT image with axial and coronal reconstructions,the three-dimensional image was judged by the surgeons as better for operation planning and consistently described as useful.CONCLUSION:A 3D-image of the pancreas repre-sents an invaluable aid to the surgeon.However,the 3D-software must be further developed in order to be integrated into daily clinical routine.
文摘The China Seismo-Electromagnetic Satellite(CSES) is the first platform of China's earthquake observation system in space and the first satellite of China's geophysical field detection missions. The high precision magnetometer(HPM), which contains two fluxgate sensors and a coupled dark state magnetometer(CDSM), measures the vector of the Earth's magnetic field with a bandwidth from DC to 15 Hz. The two fluxgate sensors are in a gradiometer configuration in order to reduce satellite interferences. Additionally, the CDSM sensor measures the scalar value of the magnetic field with higher accuracy and stability.Several data processing and calibration methods have been prepared to get accurate vector magnetic field data. This includes the calibration of each of the three sensors, the absolute vector correction algorithm, the spacecraft magnetic interference elimination and the coordinate transformation method. Also the instrument performances based on ground calibration activities are shown in this article.
文摘Water quality of the river Nile and trace elements of the water, sediments and fish tissues were investigated in the current work. Eighteen different sampling points were selected along the whole course of the River Nile from its spring at Aswan to its estuaries at Rosetta and Damietta. Higher mean value of conductivity, alkalinity, chemical oxygen demand (COD), total organic carbon (TOC), ammonia (NH3), nitrate (NO3), total solid (TS), sulphate (SO4), chloride (Cl), orthophosphate were recorded in the water of Damietta and Rosetta branches comparing to other sites. Also trace metals in the water, sediments and tissues of Clarias gariepinus increased significantly (P Fe > Cu > Pb > Mn > Cr> Cd > Hg. In the gill tissues theses metals were accumulated in the following order Fe > Zn > Mn > Pb > Cr > Cu > Cd> Hg. The low accumulation of metals in muscle may be due to lack of binding affinity of these metals with the proteins of muscle. This is particularly important because muscles contribute the greatest mass of the flesh that is consumed as food.
文摘AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on the differentiation of colonic lamina propria fibroblasts (CLPF) into myofibroblasts in vitro.METHODS: Primary CLPF cultures were incubated with TGF-β1 and analyzed for production of m-smooth muscle actin (α-SMA), fibronectin (FN) and FN isoforms. Migration assays were performed in a modified 48-well Boyden chamber. Levels of total and phosphorylated focal adhesion kinase (FAK) in CLPF were analyzed after induction of migration.did not change α-SMA levels, while TGF-β1 treatment for 6 d significantly increased α-SIVlA production. Short term incubation (6 h) with TGF-β1 enhanced CLPF migration, while long term treatment (6 d) of CLPF with TGF-β1 reduced migration to 15%-37% compared to untreated cells. FN and FN isoform mRNA expression were increased after short term incubation with TGF-β1 (2 d) in contrast to long term incubation with TGF-β1 for 6 d. After induction of migration, TGF-β1-preincubated CLPF showed higher amounts of FN and its isoforms and lower levels of total and phosphorylated FAK than untreated cells.CONCLUSION: Long term incubation of CLPF with TGF-β1 induced differentiation into myofibroblasts with enhanced α-SMA, reduced migratory potential and FAK phosphorylation, and increased FN production. In contrast, short term contact (6 h) of fibroblasts with TGF-β1 induced a dose-dependent increase of cell migration and FAK phosphorylation without induction of α-SMA production.