The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia ...The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia solani and on the mycelium growth, conidial formation, germination, appressorium formation of Magnaporthe grisea. The results showed that the antifungal monomer component DZP8 has strong antifungal effect on both the R. solani and M. grisea. The EC50 and EC90 of DZP8 were 1.81 and 3.35 μg/ml on Ft. solani respectively, and 37.01 and 136.21 μg/ml on M. grisea respectively. Under the treatment of 48.01 μg/ml DZP8, the sclerotium formation rate of R. solani was just 39.21%, the formation time delayed by 216 h and the dry weight decreased by 81.37% in comparison the con- trol; and 33.51 μg/ml DZP8 significantly inhibited the sclerotium germination. In the presence of 160.08 μg/ml DZP8, the sporulation of M. grisea was just 9.29% of control sample; 20.14 μg/ml DZP8 inhibited the conidial germination suppression rate by 95.16%, and the appressorium formation by 100%.展开更多
Aim L-Arginine· L-aspartate, a double salt, has been recently reported toinhibit platelet aggregation and thrombosis, but its action mechanism is not clear yet. This studywas conducted to investigate its effect o...Aim L-Arginine· L-aspartate, a double salt, has been recently reported toinhibit platelet aggregation and thrombosis, but its action mechanism is not clear yet. This studywas conducted to investigate its effect on FITC-PAC-1, an anti-glycoprotein IIb/IIIa monoclonalantibody binding to activated platelets, and on correlative autacoid levels in plasma or inplatelets in order to explore its potential pathway of inhibiting platelet aggregation andthrombosis. Methods Monoclonal antibody binding to activated platelets was assayed by flowcytometry; NO was assessed by colorimetric method. cAMP, TXB_2 or 6-keto-PGF_(1α) levels wereassessed by radioimmunoassay. Results Gavaged 30 mg·kg^(-1) of L-arginine·L-aspartate increasedboth concentration of NO in plasma and 6-keto-PGF_(1) in incubated supernatant of aortic segment ofrats ex vivo (P < 0.05), but it did not influence cAMP content in platelets and the level of TXB_2or 6-keto-PGF_(1) in plasma of rats, whereas ASA significantly lowered TXB_2 or 6-keto-PGF_(1α) inplasma. Both 100 μmol-L^(-1) of L-arginine ·L-aspartate and ASA inhibited FITC-PAC-1 binding toactivated platelets in vitro. Conclusion The increase in NO and PGI_2 release from endo-thelialcells and consequent inhibition of platelet activation may contribute to the inhibition of plateletaggregation and thrombosis by L-arginine· L-aspartate; whereas arachidonic acid or cAMP metabolicpathway is not closely correlative with the studied effect.展开更多
The effects of auxin polar transport inhibitors, 9-hydroxy-fluorene-9-carboxylic acid (HFCA); 2, 3, 5-triiodobenzoic acid (TIBA) and trans-cinnamic acid (CA)on leaf pattern formation were investigated with shoots form...The effects of auxin polar transport inhibitors, 9-hydroxy-fluorene-9-carboxylic acid (HFCA); 2, 3, 5-triiodobenzoic acid (TIBA) and trans-cinnamic acid (CA)on leaf pattern formation were investigated with shoots formed from cultured leaf explants of tobacco and cultured pedicel explants of Orychophragmus violaceus, and the seedlings of tobacco and Brassica chinensis. Although the effective concentration varies with the inhibitors used, all of the inhibitors induced the formation of trumpet-shaped and/or fused leaves. The frequency of trumpet-shaped leaf formation was related to the concentration of inhibitors in the medium.Histological observation of tobacco seedlings showed that there was only one main vascular bundle and several minor vascular bundles in normal leaves of the control, but there were several vascular bundles of more or less the same size in the trumpet-shaped leaves of treated ones.These results indicated that auxin polar transport played an important role on bilateral symmetry of leaf growth.展开更多
For the recycling of Pd and Ag from high-level liquid waste(HLLW), the electrochemical behaviors of Pd and Ag in the simulated HNO_(3) solutions were investigated by cyclic voltammetry and potentiostatic deposition.Sc...For the recycling of Pd and Ag from high-level liquid waste(HLLW), the electrochemical behaviors of Pd and Ag in the simulated HNO_(3) solutions were investigated by cyclic voltammetry and potentiostatic deposition.Scanning electron microscopy(SEM) and X-ray diffraction(XRD) were used to-observe the deposits morphology and to evaluate their composition. The results indicate that the formation of NO_(2)^(-)electrodeposited. When Pd and Ag are electrodeposited together, more metals are gained in the same time, and the deposited Ag does not dissolve in this situation. The metals are electrodeposited completely at the potentials from -0.4 to -0.6 V(vs MSE) and the deposits contai-n Ag and PdHx. The electrodeposition of Pd can boost h-ydrogen evolution,and then the reaction between H;and NO_(2)^(-)is sped up, thereby lowering the concentration of NO_(2)^(-)and inhibiting the dissolution of Ag.展开更多
Jianshanzi volcanic rocks at Qinghe valley in the northern Liaoning were considered belonging to Early Proterozoie Gaojiayu Formation of Liaohe Group, or to Early Cambrian Beidagou Formation of Qinghezhen Group, or Mi...Jianshanzi volcanic rocks at Qinghe valley in the northern Liaoning were considered belonging to Early Proterozoie Gaojiayu Formation of Liaohe Group, or to Early Cambrian Beidagou Formation of Qinghezhen Group, or Middle-Late Proterozoic Shenjiapu Formation-Complex of Kaiyuan Group-complex. Dating the zircons from the dacite with schistosity is 2 506 Ma in method of U-Pb (SHRIMP). This evidence indicates the rocks may be referred to Late Permian in age. Discovery of the rocks is significant to re-recognize stratigraphic property of "Liaohe Group", regional geoteetonie location and revolution of orogenic zone in Qinghe valley of the northern Liaoning.展开更多
While research on pedogenesis mainly focuses on long-term soil formation and most often neglects recent soil evolution in response to human practices or climate changes, this article reviews the impact of artificial s...While research on pedogenesis mainly focuses on long-term soil formation and most often neglects recent soil evolution in response to human practices or climate changes, this article reviews the impact of artificial subsurface drainage on soil evolution. Artificial drainage is considered as an example of the impact of recent changes in water fluxes on soil evolution over time scales of decades to a century. Results from various classical studies on artificial drainage including hydrological and environmental studies are reviewed and collated with rare studies dealing explicitly with soil morphology changes, in response to artificial drainage. We deduce that soil should react to the perturbations associated with subsurface drainage over time scales that do not exceeding a few decades. Subsurface drainage decreases the intensity of erosion and must i) increase the intensity of the lixiviation and eluviation processes, ii) affect iron and manganese dynamics, and iii) induce heterogeneities in soil evolution at the ten meter scale. Such recent soil evolutions can no longer be neglected as they are mostly irreversible and will probably have unknown, but expectable, feedbacks on crucial soil functions such as the sequestration of soil organic matter or the water available capacity.展开更多
Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in v...Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in vitro. The effect on proliferation of HUVECs and HeLa cells was examined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and apoptosis of these cells monitored by flow cytometry. The effect on migration of HUVECs and HeLa cells was examined by Boyden chamber. Twenty colon carcinoma-bearing C67BL/6 mice were used to investigate the antitumor effects of arresten protein. The mice were randomly divided into arresten treatment group (n=10) and control group (n=10). The microvessel densities of the tumors were measured by immunohistochemical staining with anti-CD31 monoclonal antibody. Results Arresten inhibited the proliferation and migration of HUVECs in a dose-dependent manner while promoting apoptosis. However, arresten had no significant effects on the proliferation and apoptosis of HeLa cells. The migration of HeLa cells was modestly inhibited by arresten. The arresten treatment group of mice showed no weight loss or unusual behavior during the course of treatment, and the tumor growth was significantly decreased; in contrast, the control group of mice exhibited rapidly growing tumors and cachexia. A dramatically decreased microvessel density in tumor tissues was found in arresten-treated mice compared with that in the control mice. Conclusion Arresten can inhibit tumor growth through inhibition of tumor angiogenesis.展开更多
BM-13 505 is a new type of thromboxane receptor antagonist developed firstabfoad and synthesized in our school.wita modife method recently。The resultS of our study showed that the occlusion time of carotid artery in ...BM-13 505 is a new type of thromboxane receptor antagonist developed firstabfoad and synthesized in our school.wita modife method recently。The resultS of our study showed that the occlusion time of carotid artery in experimental thrombosis rats was prolonged by BM-13505,0.45 and 0.23 mglkg iv fP<0.00 1 and <0.01 respectively).B·13505 2 mgjkg iv ef fectively prevented the cerebral thrombosis caused by AA 4 mg/kg in rats(P<0.01) BM-13505 10 mg/kg ip prevented the AA-induced pulmonary thrombosis in mice(P<0.01).Tail bleeding time of mice was prolonged by this dru.BM-13505 significantly inhibited the AA-induced rabbit platelet aggregation,with an IC ̄(50) of0.17 μmol/L; ADp-and collagen-induced aggregations were not affected.TXB_2 level in platelets and that in mice plasma were decreased by BM-13505,but cAMP level inplatelets was not affected. BM-13505 may be possibly developed into a useful anti-platelet and anti-thromboti c drug。展开更多
The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the s...The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the solidus and liquidus temperatures, the melting range and the sensitivity of the solid fraction at the thixoforming temperatures.The rheology of aluminium alloy A201 was examined using a high temperature Searle rheometer.The flow behaviour was analyzed with concentric cylinders of graphite to avoid chemical interactions with the liquid or semi-solid aluminium.The rotational body was grooved to prevent a phenomenon called wall slippage.Continuous cooling experiment was used to observe the shear rate effects on the flow behaviour.It can be seen that the viscosity level decreases at higher shear rates.Shear rate jump experiment was carried out to evaluate the steady state flow curve within the analyzed shear rate range from 60 s-1 to 260 s-1.It is found that the power law indexes are-1.35 and-1.49 for 35% and 45% solid fraction, respectively.Finally, some mechanical property data of as-cast and as-thixoformed A201 alloy are included indicating the potential for high strength applications.展开更多
Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO T...Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system (Tlf) is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.展开更多
The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in ...The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in the theoretical and experimental studies on the vdW interaction in bimolecular reactions. In particular, we review those studies that have advanced our understanding of how the vdW interaction can strongly influence the dynamics in both direct activated and complex-forming reactions, and further extend the discussion to the polyatomic reactions involving more atoms and those occurring at cold and ultracold temperatures. We indicate that an accurate description of the delicate vdW structure and long-range potential remains a challenge nowadays in either ab initio calculations or the fitting of the potential energy surfaces. We also present an explanation on the concept of vdW saddle proposed by us recently which may have general importance.展开更多
Objective: To observe osteogenetic rate of alveolar bone on the tension side in orthodontic tooth movement through distraction osteogenesis of the periodental ligament quantificationally. Methods: The experiment was c...Objective: To observe osteogenetic rate of alveolar bone on the tension side in orthodontic tooth movement through distraction osteogenesis of the periodental ligament quantificationally. Methods: The experiment was carried in 6 dogs. The left side of jaws of each one was set as test or control side, and the other side was control or test side. On the control side, the first premorlar was moved by traditional method on the test side. A self-made distraction device was used on the test side. The newly formed alveolar bone on the tension side of moved tooth was labeled by serial tetracycline fluorochrome. Sections were observed by fluorescence microscope and pictured. Newly formed bone was measured by computer image analysis. Results: The quantity of newly formed bone was significantly different between the two methods. Newly formed bone in rapid tooth movement by distraction osteogenesis of the periodental ligament was more than that in traditional method. Conclusion: The distraction through periodental ligament could induce more rapid bone formation and excite higher osteogenetic activity than traditional method.展开更多
This paper aims at showing how rhetoric and meaning in Zambian poetry interact. The work analyses the definition of poetry and gives the understanding that poetry is an artistic use of language that employs figurative...This paper aims at showing how rhetoric and meaning in Zambian poetry interact. The work analyses the definition of poetry and gives the understanding that poetry is an artistic use of language that employs figurative language for maximum effect. The work also analyses rhetoric and concludes that the sole aim of rhetoric is to persuade the audience. The use of this rhetoric is later identified as a preoccupation of most poets. After studying a number of rhetorical devices used in poetry, the work has studied selected Zambian poems and focussed on the use of rhyme and alliteration in the poems. It has been shown that there is much use of rhyme but with limited use of alliteration. In both cases, the use is not so much to the contribution to the meaning in the poetry. The poets usually use these devices for the sake of beauty and not meaning. The paper therefore suggests that poets could undergo some formal training in composition while the art is also taught to the young while in their early years in schools.展开更多
Deep venous thrombosis (DVT) is an important cause of disability and mortality after major orthopedic surgery. The roles of perioperative treatment and prevention of DVT in patients with femoral neck fractures who r...Deep venous thrombosis (DVT) is an important cause of disability and mortality after major orthopedic surgery. The roles of perioperative treatment and prevention of DVT in patients with femoral neck fractures who require major surgery have not yet been well explored in Chinese clinical practice. Here we report a case of calf muscular venous thrombosis in a 55-year-old woman with femoral neck fracture before surgery. Preventive and treatment measures including the administration of heparin sodium, application of venous foot pump and placement of inferior vena cava filter were taken. The condition of the patient was stable during the perioperative period and the surgery was successful. Besides, postoperative examination showed that the femur healed well and the functional recovery was satisfactory. Our results suggest that femoral neck fracture patients combined with DVT can receive surgery after accurate preoperative assessment and proper preoperative treatment.展开更多
The effects of Sn and Ga additions on the glass forming ability (GFA) of (A186LasNi9)100_xSnx(x=0, 0.2, 0.3, 0.5, 0.7, 1 and 2 at.%) and (Al86LasNi9)100_xGax(x=0, 0.2, 0.5, 1 and 1.5 at.%) alloys were system...The effects of Sn and Ga additions on the glass forming ability (GFA) of (A186LasNi9)100_xSnx(x=0, 0.2, 0.3, 0.5, 0.7, 1 and 2 at.%) and (Al86LasNi9)100_xGax(x=0, 0.2, 0.5, 1 and 1.5 at.%) alloys were systematically investigated. Unlike common microal- loying methods, both Sn and Ga have a positive heat of mixing with the main component of A1. Our analysis confirmed that proper Sn addition can suppress the strong formation of a-A1 and enhance the GFA due to the positive heat of mixing between Sn and AI and the large difference in their atomic sizes. While the addition of Ga to the base alloy acted as the nucleation cites for ct-Al and accelerated precipitation of the ct-A1 phase, thus deteriorating the GFA.展开更多
The Jiaodong Peninsula is the largest repository of gold in China based on the production in history. It covers less than 0.2% of China's territory, but production of gold accounts for about one fourth of the whol...The Jiaodong Peninsula is the largest repository of gold in China based on the production in history. It covers less than 0.2% of China's territory, but production of gold accounts for about one fourth of the whole country. Thus, the Jiaodong Peninsula is a typical area or case of large-scale metallogenesis and a large clusters of mineral deposits in China. It is characterized by the large clusters of gold deposits in large scale, high reserve and short mineralizing stage. In this study, we suggest that the eastern boundary of the large clusters of gold deposits is as same as that of North China Block, the gold deposits are hosted by Archean metamorphic rocks or Mesozoic granites, and the age of gold mineralization is 121.6 to 122.7 Ma. Gold and related ore-forming materials are derived from multisources, i.e. Archean metamorphic rocks, granites and intermediate-mafic dikes, especially, intermediate-mafic dikes and calc-alkaline granites. The metallogenic geodynamic process is constrained by the tectonic evolution of eastern North China Block during Late Mesozoic, and it is the result of the interaction between mantle and crust as the boundary plates are playing role on the block.展开更多
We present computational results on the evolution of the shock-accelerated heavy bubbles surrounded by nitrogen with the Atwood number At = 0.497–0.677 and the emphasis is on the jet phenomenon caused by the shock fo...We present computational results on the evolution of the shock-accelerated heavy bubbles surrounded by nitrogen with the Atwood number At = 0.497–0.677 and the emphasis is on the jet phenomenon caused by the shock focusing. The multi-fluid Eulerian equation is solved by a finite volume method based on MUSCL-Hancock approach. Based on the numerical schlieren and the distributions of density and pressure, it is found that there are three typical jet structures(outward jet, no jet, inward jet) for different combinations of gas mixture inside the bubble which determine the position of shock focusing relative to the downstream pole of the heavy bubble(upstream of the pole, at the pole, downstream the pole). Compared with the inward jet, the velocity of outward jet is obviously larger. As At increases, the moment of jet formation is postponed, and the maximal values and magnifications of pressure and density increase distinctly. Therefore, the energy convergence effects are heavily enhanced with the increase of bubble gas density.展开更多
基金Supported by National Natural Science Foundation of China(31071724)Natural Science Foundation of Jiangxi Province(2010GZN0037)~~
文摘The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia solani and on the mycelium growth, conidial formation, germination, appressorium formation of Magnaporthe grisea. The results showed that the antifungal monomer component DZP8 has strong antifungal effect on both the R. solani and M. grisea. The EC50 and EC90 of DZP8 were 1.81 and 3.35 μg/ml on Ft. solani respectively, and 37.01 and 136.21 μg/ml on M. grisea respectively. Under the treatment of 48.01 μg/ml DZP8, the sclerotium formation rate of R. solani was just 39.21%, the formation time delayed by 216 h and the dry weight decreased by 81.37% in comparison the con- trol; and 33.51 μg/ml DZP8 significantly inhibited the sclerotium germination. In the presence of 160.08 μg/ml DZP8, the sporulation of M. grisea was just 9.29% of control sample; 20.14 μg/ml DZP8 inhibited the conidial germination suppression rate by 95.16%, and the appressorium formation by 100%.
文摘Aim L-Arginine· L-aspartate, a double salt, has been recently reported toinhibit platelet aggregation and thrombosis, but its action mechanism is not clear yet. This studywas conducted to investigate its effect on FITC-PAC-1, an anti-glycoprotein IIb/IIIa monoclonalantibody binding to activated platelets, and on correlative autacoid levels in plasma or inplatelets in order to explore its potential pathway of inhibiting platelet aggregation andthrombosis. Methods Monoclonal antibody binding to activated platelets was assayed by flowcytometry; NO was assessed by colorimetric method. cAMP, TXB_2 or 6-keto-PGF_(1α) levels wereassessed by radioimmunoassay. Results Gavaged 30 mg·kg^(-1) of L-arginine·L-aspartate increasedboth concentration of NO in plasma and 6-keto-PGF_(1) in incubated supernatant of aortic segment ofrats ex vivo (P < 0.05), but it did not influence cAMP content in platelets and the level of TXB_2or 6-keto-PGF_(1) in plasma of rats, whereas ASA significantly lowered TXB_2 or 6-keto-PGF_(1α) inplasma. Both 100 μmol-L^(-1) of L-arginine ·L-aspartate and ASA inhibited FITC-PAC-1 binding toactivated platelets in vitro. Conclusion The increase in NO and PGI_2 release from endo-thelialcells and consequent inhibition of platelet activation may contribute to the inhibition of plateletaggregation and thrombosis by L-arginine· L-aspartate; whereas arachidonic acid or cAMP metabolicpathway is not closely correlative with the studied effect.
文摘The effects of auxin polar transport inhibitors, 9-hydroxy-fluorene-9-carboxylic acid (HFCA); 2, 3, 5-triiodobenzoic acid (TIBA) and trans-cinnamic acid (CA)on leaf pattern formation were investigated with shoots formed from cultured leaf explants of tobacco and cultured pedicel explants of Orychophragmus violaceus, and the seedlings of tobacco and Brassica chinensis. Although the effective concentration varies with the inhibitors used, all of the inhibitors induced the formation of trumpet-shaped and/or fused leaves. The frequency of trumpet-shaped leaf formation was related to the concentration of inhibitors in the medium.Histological observation of tobacco seedlings showed that there was only one main vascular bundle and several minor vascular bundles in normal leaves of the control, but there were several vascular bundles of more or less the same size in the trumpet-shaped leaves of treated ones.These results indicated that auxin polar transport played an important role on bilateral symmetry of leaf growth.
基金the financial supports from the National Natural Science Foundation of China (No. 11975082)。
文摘For the recycling of Pd and Ag from high-level liquid waste(HLLW), the electrochemical behaviors of Pd and Ag in the simulated HNO_(3) solutions were investigated by cyclic voltammetry and potentiostatic deposition.Scanning electron microscopy(SEM) and X-ray diffraction(XRD) were used to-observe the deposits morphology and to evaluate their composition. The results indicate that the formation of NO_(2)^(-)electrodeposited. When Pd and Ag are electrodeposited together, more metals are gained in the same time, and the deposited Ag does not dissolve in this situation. The metals are electrodeposited completely at the potentials from -0.4 to -0.6 V(vs MSE) and the deposits contai-n Ag and PdHx. The electrodeposition of Pd can boost h-ydrogen evolution,and then the reaction between H;and NO_(2)^(-)is sped up, thereby lowering the concentration of NO_(2)^(-)and inhibiting the dissolution of Ag.
文摘Jianshanzi volcanic rocks at Qinghe valley in the northern Liaoning were considered belonging to Early Proterozoie Gaojiayu Formation of Liaohe Group, or to Early Cambrian Beidagou Formation of Qinghezhen Group, or Middle-Late Proterozoic Shenjiapu Formation-Complex of Kaiyuan Group-complex. Dating the zircons from the dacite with schistosity is 2 506 Ma in method of U-Pb (SHRIMP). This evidence indicates the rocks may be referred to Late Permian in age. Discovery of the rocks is significant to re-recognize stratigraphic property of "Liaohe Group", regional geoteetonie location and revolution of orogenic zone in Qinghe valley of the northern Liaoning.
文摘While research on pedogenesis mainly focuses on long-term soil formation and most often neglects recent soil evolution in response to human practices or climate changes, this article reviews the impact of artificial subsurface drainage on soil evolution. Artificial drainage is considered as an example of the impact of recent changes in water fluxes on soil evolution over time scales of decades to a century. Results from various classical studies on artificial drainage including hydrological and environmental studies are reviewed and collated with rare studies dealing explicitly with soil morphology changes, in response to artificial drainage. We deduce that soil should react to the perturbations associated with subsurface drainage over time scales that do not exceeding a few decades. Subsurface drainage decreases the intensity of erosion and must i) increase the intensity of the lixiviation and eluviation processes, ii) affect iron and manganese dynamics, and iii) induce heterogeneities in soil evolution at the ten meter scale. Such recent soil evolutions can no longer be neglected as they are mostly irreversible and will probably have unknown, but expectable, feedbacks on crucial soil functions such as the sequestration of soil organic matter or the water available capacity.
基金Supported by Key Scientific and Technological Project of Shanxi Province (042082)Technological and Engineering Project of the Department of Education of Shanxi Province (20080017)
文摘Objective To examine the inhibitory effects of recombinant purified arresten on tumor formation. Methods Purified arresten protein was incubated with human umbilical vein endothelial cells (HUVECs) and HeLa cells in vitro. The effect on proliferation of HUVECs and HeLa cells was examined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and apoptosis of these cells monitored by flow cytometry. The effect on migration of HUVECs and HeLa cells was examined by Boyden chamber. Twenty colon carcinoma-bearing C67BL/6 mice were used to investigate the antitumor effects of arresten protein. The mice were randomly divided into arresten treatment group (n=10) and control group (n=10). The microvessel densities of the tumors were measured by immunohistochemical staining with anti-CD31 monoclonal antibody. Results Arresten inhibited the proliferation and migration of HUVECs in a dose-dependent manner while promoting apoptosis. However, arresten had no significant effects on the proliferation and apoptosis of HeLa cells. The migration of HeLa cells was modestly inhibited by arresten. The arresten treatment group of mice showed no weight loss or unusual behavior during the course of treatment, and the tumor growth was significantly decreased; in contrast, the control group of mice exhibited rapidly growing tumors and cachexia. A dramatically decreased microvessel density in tumor tissues was found in arresten-treated mice compared with that in the control mice. Conclusion Arresten can inhibit tumor growth through inhibition of tumor angiogenesis.
文摘BM-13 505 is a new type of thromboxane receptor antagonist developed firstabfoad and synthesized in our school.wita modife method recently。The resultS of our study showed that the occlusion time of carotid artery in experimental thrombosis rats was prolonged by BM-13505,0.45 and 0.23 mglkg iv fP<0.00 1 and <0.01 respectively).B·13505 2 mgjkg iv ef fectively prevented the cerebral thrombosis caused by AA 4 mg/kg in rats(P<0.01) BM-13505 10 mg/kg ip prevented the AA-induced pulmonary thrombosis in mice(P<0.01).Tail bleeding time of mice was prolonged by this dru.BM-13505 significantly inhibited the AA-induced rabbit platelet aggregation,with an IC ̄(50) of0.17 μmol/L; ADp-and collagen-induced aggregations were not affected.TXB_2 level in platelets and that in mice plasma were decreased by BM-13505,but cAMP level inplatelets was not affected. BM-13505 may be possibly developed into a useful anti-platelet and anti-thromboti c drug。
基金the "Ministerio de Ciencia e Innovación" and to the "Fondos FEDER",project "Integrauto" PSE-370000-2008-03the Basque Government,project "ETORTEK, Manufacturing 0.0 II",for their financial support
文摘The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the solidus and liquidus temperatures, the melting range and the sensitivity of the solid fraction at the thixoforming temperatures.The rheology of aluminium alloy A201 was examined using a high temperature Searle rheometer.The flow behaviour was analyzed with concentric cylinders of graphite to avoid chemical interactions with the liquid or semi-solid aluminium.The rotational body was grooved to prevent a phenomenon called wall slippage.Continuous cooling experiment was used to observe the shear rate effects on the flow behaviour.It can be seen that the viscosity level decreases at higher shear rates.Shear rate jump experiment was carried out to evaluate the steady state flow curve within the analyzed shear rate range from 60 s-1 to 260 s-1.It is found that the power law indexes are-1.35 and-1.49 for 35% and 45% solid fraction, respectively.Finally, some mechanical property data of as-cast and as-thixoformed A201 alloy are included indicating the potential for high strength applications.
基金supported by the CAS West-Developing Initiative (Grant No. KZCX2-XB2-07)the Key Technologies R & D Program of China (Grant No. 2008BAD98B04)
文摘Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system (Tlf) is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.
基金supported by the National Natural Science Foundation of China (No.21773251 and No.91741106)the Beijing National Laboratory for Molecular Sciences and Chinese Academy of Sciences
文摘The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in the theoretical and experimental studies on the vdW interaction in bimolecular reactions. In particular, we review those studies that have advanced our understanding of how the vdW interaction can strongly influence the dynamics in both direct activated and complex-forming reactions, and further extend the discussion to the polyatomic reactions involving more atoms and those occurring at cold and ultracold temperatures. We indicate that an accurate description of the delicate vdW structure and long-range potential remains a challenge nowadays in either ab initio calculations or the fitting of the potential energy surfaces. We also present an explanation on the concept of vdW saddle proposed by us recently which may have general importance.
基金Supported by the Youth Science Foundation of Stomatological Hospital, Xi'an Jiaotong University
文摘Objective: To observe osteogenetic rate of alveolar bone on the tension side in orthodontic tooth movement through distraction osteogenesis of the periodental ligament quantificationally. Methods: The experiment was carried in 6 dogs. The left side of jaws of each one was set as test or control side, and the other side was control or test side. On the control side, the first premorlar was moved by traditional method on the test side. A self-made distraction device was used on the test side. The newly formed alveolar bone on the tension side of moved tooth was labeled by serial tetracycline fluorochrome. Sections were observed by fluorescence microscope and pictured. Newly formed bone was measured by computer image analysis. Results: The quantity of newly formed bone was significantly different between the two methods. Newly formed bone in rapid tooth movement by distraction osteogenesis of the periodental ligament was more than that in traditional method. Conclusion: The distraction through periodental ligament could induce more rapid bone formation and excite higher osteogenetic activity than traditional method.
文摘This paper aims at showing how rhetoric and meaning in Zambian poetry interact. The work analyses the definition of poetry and gives the understanding that poetry is an artistic use of language that employs figurative language for maximum effect. The work also analyses rhetoric and concludes that the sole aim of rhetoric is to persuade the audience. The use of this rhetoric is later identified as a preoccupation of most poets. After studying a number of rhetorical devices used in poetry, the work has studied selected Zambian poems and focussed on the use of rhyme and alliteration in the poems. It has been shown that there is much use of rhyme but with limited use of alliteration. In both cases, the use is not so much to the contribution to the meaning in the poetry. The poets usually use these devices for the sake of beauty and not meaning. The paper therefore suggests that poets could undergo some formal training in composition while the art is also taught to the young while in their early years in schools.
文摘Deep venous thrombosis (DVT) is an important cause of disability and mortality after major orthopedic surgery. The roles of perioperative treatment and prevention of DVT in patients with femoral neck fractures who require major surgery have not yet been well explored in Chinese clinical practice. Here we report a case of calf muscular venous thrombosis in a 55-year-old woman with femoral neck fracture before surgery. Preventive and treatment measures including the administration of heparin sodium, application of venous foot pump and placement of inferior vena cava filter were taken. The condition of the patient was stable during the perioperative period and the surgery was successful. Besides, postoperative examination showed that the femur healed well and the functional recovery was satisfactory. Our results suggest that femoral neck fracture patients combined with DVT can receive surgery after accurate preoperative assessment and proper preoperative treatment.
基金supported by the National Natural Science Foundation of China(Grant Nos.51010001 and 51001009)the 111 Project(Grant No.B07003)the Program for Changjiang Scholars and Innovative Research Team in University
文摘The effects of Sn and Ga additions on the glass forming ability (GFA) of (A186LasNi9)100_xSnx(x=0, 0.2, 0.3, 0.5, 0.7, 1 and 2 at.%) and (Al86LasNi9)100_xGax(x=0, 0.2, 0.5, 1 and 1.5 at.%) alloys were systematically investigated. Unlike common microal- loying methods, both Sn and Ga have a positive heat of mixing with the main component of A1. Our analysis confirmed that proper Sn addition can suppress the strong formation of a-A1 and enhance the GFA due to the positive heat of mixing between Sn and AI and the large difference in their atomic sizes. While the addition of Ga to the base alloy acted as the nucleation cites for ct-Al and accelerated precipitation of the ct-A1 phase, thus deteriorating the GFA.
基金by the Ministry of Science and Technology of China (Grant No.G1999043207), Chinese Academy of Sciences (Grant No. KZCX1-07) and National Natural Science Foundation of China (Grant No. 49872064).
文摘The Jiaodong Peninsula is the largest repository of gold in China based on the production in history. It covers less than 0.2% of China's territory, but production of gold accounts for about one fourth of the whole country. Thus, the Jiaodong Peninsula is a typical area or case of large-scale metallogenesis and a large clusters of mineral deposits in China. It is characterized by the large clusters of gold deposits in large scale, high reserve and short mineralizing stage. In this study, we suggest that the eastern boundary of the large clusters of gold deposits is as same as that of North China Block, the gold deposits are hosted by Archean metamorphic rocks or Mesozoic granites, and the age of gold mineralization is 121.6 to 122.7 Ma. Gold and related ore-forming materials are derived from multisources, i.e. Archean metamorphic rocks, granites and intermediate-mafic dikes, especially, intermediate-mafic dikes and calc-alkaline granites. The metallogenic geodynamic process is constrained by the tectonic evolution of eastern North China Block during Late Mesozoic, and it is the result of the interaction between mantle and crust as the boundary plates are playing role on the block.
基金supported by the National Natural Science Foundation of China(Grant Nos.11172278,11302201,11472253 and 11202195)Science Foundation of China Academy of Engineering Physics(Grant No.2014B0201017)
文摘We present computational results on the evolution of the shock-accelerated heavy bubbles surrounded by nitrogen with the Atwood number At = 0.497–0.677 and the emphasis is on the jet phenomenon caused by the shock focusing. The multi-fluid Eulerian equation is solved by a finite volume method based on MUSCL-Hancock approach. Based on the numerical schlieren and the distributions of density and pressure, it is found that there are three typical jet structures(outward jet, no jet, inward jet) for different combinations of gas mixture inside the bubble which determine the position of shock focusing relative to the downstream pole of the heavy bubble(upstream of the pole, at the pole, downstream the pole). Compared with the inward jet, the velocity of outward jet is obviously larger. As At increases, the moment of jet formation is postponed, and the maximal values and magnifications of pressure and density increase distinctly. Therefore, the energy convergence effects are heavily enhanced with the increase of bubble gas density.