A multidisciplinary approach-anatomy, histochemistry and phytochemistry-was used to investigate the leaf structure, the content and the storage location of barbaloin in the leaves of Aloe vera L. var. chinensis (Haw.)...A multidisciplinary approach-anatomy, histochemistry and phytochemistry-was used to investigate the leaf structure, the content and the storage location of barbaloin in the leaves of Aloe vera L. var. chinensis (Haw.) Berg. Xeromorphic characteristics including secondary thickened epidermal cell walls, thicker cuticle, ambiguous differentiation of spongy and palisade tissues in the chlorenchyma, and well-developed aquiferous tissue could be seen in the leaves. Several large parenchymatous cells were observed at the phloem pole of the first ring of vascular bundles. The secondary ring of vascular bundles in the leaf base and the stomata, which are surrounded by five cells, have some classification significance in this species. The density of vascular bundles, the content of barbaloin and the intensity of histochemical reaction differed among leaf numbers Ll (annual leaf), L2 (biennial leaf), L3 (triennial leaf) and L4 (quadrennial leaf), and in different parts of the leaf. These three factors were highest in the youngest leaf, Ll, and top parts of all the leaves and lowest in the basal parts and the oldest leaf, L4. The density of vascular bundles had a positive correlation to the content of barbaloin. The histochemical results revealed that the small sheath cells that surrounded the bundles might be the location of barbaloin synthesis and the large parenchymatous cells beneath the sheath might be the storage places of this metabolite.展开更多
The development of unconventional resources, such as shale gas and tight sane gas, requires the integration of multi-disciplinary knowledge to resolve many engineering problems in order to achieve economic production ...The development of unconventional resources, such as shale gas and tight sane gas, requires the integration of multi-disciplinary knowledge to resolve many engineering problems in order to achieve economic production levels. The reservoir heterogeneit3 revealed by different data sets, such as 3D seismic and microseismic data, can more full3 reflect the reservoir properties and is helpful to optimize the drilling and completioT programs. First, we predict the local stress direction and open or close status of the natura fractures in tight sand reservoirs based on seismic curvature, an attribute that reveals reservoi heterogeneity and geomechanical properties. Meanwhile, the reservoir fracture network is predicted using an ant-tracking cube and the potential fracture barriers which can affec hydraulic fracture propagation are predicted by integrating the seismic curvature attribute anc ant-tracking cube. Second, we use this information, derived from 3D seismic data, to assis in designing the fracture program and adjusting stimulation parameters. Finally, we interpre the reason why sand plugs will occur during the stimulation process by the integration of 3E seismic interpretation and microseismic imaging results, which further explain the hydraulic fracure propagation controlling factors and open or closed state of natural fractures in tigh sand reservoirs.展开更多
Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the t...Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation （KDE） is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE（KPCA）, and ICA with KDE,（KICA）, are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator.展开更多
Undrained behaviour of sand under low cell pressure was studied in static and cyclic triaxial tests. It was found that very loose sand liquefies under static loading with the relative density being a key parameter for...Undrained behaviour of sand under low cell pressure was studied in static and cyclic triaxial tests. It was found that very loose sand liquefies under static loading with the relative density being a key parameter for the undrained behaviour of sand. In cyclic triaxial tests, pore water pressures built up during the cyclic loading and exceeded the confining cell pressure. This process was accompanied by a large sudden increase in axial deformation. The necessary number of cycles to obtain liquefaction was related to the confining cell pressure, the amplitude of cyclic loading and the relative density of sand.In addition, the patterns of pore water pressure response are different from those of sand samples with different relative densities. The test results are very useful for expounding scour mechanism around coastal structures since they relate to the low stress behaviour of the sand.展开更多
AIM To assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia during peroral endoscopic myotomy(POEM).METHODS Twenty-four patients who underwent POEM and experienced mucosal ...AIM To assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia during peroral endoscopic myotomy(POEM).METHODS Twenty-four patients who underwent POEM and experienced mucosal injury of the cardia during the procedure were retrospectively identified. Of the 24 patients, 21 had mucosal penetration and 3 had only slight mucosal damage without penetration. The 21 patients with mucosal penetration received fibrin sealant for closure at the site of penetration. Penetration-related characteristics, treatment, and recovery were reviewed for all 21 patients to assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia. Clinical data, including general characteristics, procedure-related parameters, Eckardt scores, lower esophageal sphincter pressures (LESP), and esophagogastroduodenoscopy(EGD) results, were analyzed to determine their influence on treatment success after mucosal penetration during POEM.RESULTS All 21 patients had a solitary mucosal penetration in the cardia (12 in esophageal region of the cardia, 9 in the stomach region of the cardia, and 1 in both the esophageal and stomach regions). Twelve had ahole-like penetration and 9 had a linear penetration. For those with a hole-like penetration, the mean size was 0.14 cm2 (0.02-0.32 cm2). For those with a linear penetration, the median size was 0.37 cm (0.10-1.00 cm). Closure of the mucosal penetration using fibrin sealant was performed successfully in all 21 patients(two patients required 5 m L fibrin sealant, and the remaining 19 patients required 2.5 mL). Two patients had a nasogastric tube placed for five days after POEM; the remaining 19 patients were kept fasting for 3 d. All 21 patients were discharged after a median of 5 d(range: 5-7 d) postoperatively. During a median 42 mo (range: 9-62 mo) follow-up, all 21 patients with a mucosal penetration successfully healed without the occurrence of infection, ulcer, or esophagitis. Furthermore, the median LESP decreased from 31.9 mm Hg (range: 21.9-67.1 mm Hg) preoperatively to 20.3 mm Hg (range: 6.0-41.0 mm Hg) postoperatively(P < 0.05). The median preoperative and postoperative Eckardt scores were 5.0(range; 4-10) and 1.0(range: 0-4), respectively (P < 0.05). Of the 21 patients with mucosal penetration, symptom remission, which is defined as a postoperative Eckardt score ≤ 3, was achieved in 20 patients(95.2%) indicating that mucosal penetration did not influence the success of POEM treatment if closed successfully using fibrin sealant.CONCLUSION Fibrin sealant is safe and effective for closure of mucosal penetration during POEM. Mucosal penetrations do not appear to influence the treatment success of POEM if closed successfully using fibrin sealant. Additional studies regarding the feasibility, efficacy, and safety of fibrin sealant for closure of larger mucosal penetrations is warranted.展开更多
The cutting burr is one of the common phenomena occurring in metal cutting.In this paper,the forming processes,main effect factors and change law of the cutting direction burr in orthogonal cutting have been studied a...The cutting burr is one of the common phenomena occurring in metal cutting.In this paper,the forming processes,main effect factors and change law of the cutting direction burr in orthogonal cutting have been studied and related theories are analyzed based on the cutting experiments.The result shows that:(1)the forming processes of cutting direction burr consist of normal cutting,flexure deformation of end surface of workpiece,plastic effect,continuous cutting and shear break separating in orthogonal cutting;(2)a new phenomenon is found that cutting direction burr is formed with the shear break separation of the chip and workpiece machined surfaces;(3)the size of cutting direction burr varies with workpiece materials,cutting parameters and geometric parameters of the cutting tool.展开更多
We present a two-photon three-dimensional multiparty quantum secret sharing scheme.The secret messagesare encoded by performing local operations.This is different from those quantum secret sharing protocols that all s...We present a two-photon three-dimensional multiparty quantum secret sharing scheme.The secret messagesare encoded by performing local operations.This is different from those quantum secret sharing protocols that all sharersmust make a state measurement.The merit of our protocol is the high capacity.展开更多
文摘A multidisciplinary approach-anatomy, histochemistry and phytochemistry-was used to investigate the leaf structure, the content and the storage location of barbaloin in the leaves of Aloe vera L. var. chinensis (Haw.) Berg. Xeromorphic characteristics including secondary thickened epidermal cell walls, thicker cuticle, ambiguous differentiation of spongy and palisade tissues in the chlorenchyma, and well-developed aquiferous tissue could be seen in the leaves. Several large parenchymatous cells were observed at the phloem pole of the first ring of vascular bundles. The secondary ring of vascular bundles in the leaf base and the stomata, which are surrounded by five cells, have some classification significance in this species. The density of vascular bundles, the content of barbaloin and the intensity of histochemical reaction differed among leaf numbers Ll (annual leaf), L2 (biennial leaf), L3 (triennial leaf) and L4 (quadrennial leaf), and in different parts of the leaf. These three factors were highest in the youngest leaf, Ll, and top parts of all the leaves and lowest in the basal parts and the oldest leaf, L4. The density of vascular bundles had a positive correlation to the content of barbaloin. The histochemical results revealed that the small sheath cells that surrounded the bundles might be the location of barbaloin synthesis and the large parenchymatous cells beneath the sheath might be the storage places of this metabolite.
文摘The development of unconventional resources, such as shale gas and tight sane gas, requires the integration of multi-disciplinary knowledge to resolve many engineering problems in order to achieve economic production levels. The reservoir heterogeneit3 revealed by different data sets, such as 3D seismic and microseismic data, can more full3 reflect the reservoir properties and is helpful to optimize the drilling and completioT programs. First, we predict the local stress direction and open or close status of the natura fractures in tight sand reservoirs based on seismic curvature, an attribute that reveals reservoi heterogeneity and geomechanical properties. Meanwhile, the reservoir fracture network is predicted using an ant-tracking cube and the potential fracture barriers which can affec hydraulic fracture propagation are predicted by integrating the seismic curvature attribute anc ant-tracking cube. Second, we use this information, derived from 3D seismic data, to assis in designing the fracture program and adjusting stimulation parameters. Finally, we interpre the reason why sand plugs will occur during the stimulation process by the integration of 3E seismic interpretation and microseismic imaging results, which further explain the hydraulic fracure propagation controlling factors and open or closed state of natural fractures in tigh sand reservoirs.
基金Supported by the National Natural Science Foundation of China （No.60574047） and the Doctorate Foundation of the State Education Ministry of China （No.20050335018）.
文摘Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation （KDE） is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE（KPCA）, and ICA with KDE,（KICA）, are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator.
基金supported by the National Natural Science Foundation of China(No.50009002)Minstry of Science and Technology Project(No.2001AA616020)Parts of this work were supported by the EU SCARCOST project
文摘Undrained behaviour of sand under low cell pressure was studied in static and cyclic triaxial tests. It was found that very loose sand liquefies under static loading with the relative density being a key parameter for the undrained behaviour of sand. In cyclic triaxial tests, pore water pressures built up during the cyclic loading and exceeded the confining cell pressure. This process was accompanied by a large sudden increase in axial deformation. The necessary number of cycles to obtain liquefaction was related to the confining cell pressure, the amplitude of cyclic loading and the relative density of sand.In addition, the patterns of pore water pressure response are different from those of sand samples with different relative densities. The test results are very useful for expounding scour mechanism around coastal structures since they relate to the low stress behaviour of the sand.
文摘AIM To assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia during peroral endoscopic myotomy(POEM).METHODS Twenty-four patients who underwent POEM and experienced mucosal injury of the cardia during the procedure were retrospectively identified. Of the 24 patients, 21 had mucosal penetration and 3 had only slight mucosal damage without penetration. The 21 patients with mucosal penetration received fibrin sealant for closure at the site of penetration. Penetration-related characteristics, treatment, and recovery were reviewed for all 21 patients to assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia. Clinical data, including general characteristics, procedure-related parameters, Eckardt scores, lower esophageal sphincter pressures (LESP), and esophagogastroduodenoscopy(EGD) results, were analyzed to determine their influence on treatment success after mucosal penetration during POEM.RESULTS All 21 patients had a solitary mucosal penetration in the cardia (12 in esophageal region of the cardia, 9 in the stomach region of the cardia, and 1 in both the esophageal and stomach regions). Twelve had ahole-like penetration and 9 had a linear penetration. For those with a hole-like penetration, the mean size was 0.14 cm2 (0.02-0.32 cm2). For those with a linear penetration, the median size was 0.37 cm (0.10-1.00 cm). Closure of the mucosal penetration using fibrin sealant was performed successfully in all 21 patients(two patients required 5 m L fibrin sealant, and the remaining 19 patients required 2.5 mL). Two patients had a nasogastric tube placed for five days after POEM; the remaining 19 patients were kept fasting for 3 d. All 21 patients were discharged after a median of 5 d(range: 5-7 d) postoperatively. During a median 42 mo (range: 9-62 mo) follow-up, all 21 patients with a mucosal penetration successfully healed without the occurrence of infection, ulcer, or esophagitis. Furthermore, the median LESP decreased from 31.9 mm Hg (range: 21.9-67.1 mm Hg) preoperatively to 20.3 mm Hg (range: 6.0-41.0 mm Hg) postoperatively(P < 0.05). The median preoperative and postoperative Eckardt scores were 5.0(range; 4-10) and 1.0(range: 0-4), respectively (P < 0.05). Of the 21 patients with mucosal penetration, symptom remission, which is defined as a postoperative Eckardt score ≤ 3, was achieved in 20 patients(95.2%) indicating that mucosal penetration did not influence the success of POEM treatment if closed successfully using fibrin sealant.CONCLUSION Fibrin sealant is safe and effective for closure of mucosal penetration during POEM. Mucosal penetrations do not appear to influence the treatment success of POEM if closed successfully using fibrin sealant. Additional studies regarding the feasibility, efficacy, and safety of fibrin sealant for closure of larger mucosal penetrations is warranted.
基金Supported by National Natural Science Foundation of China (No.59775071).
文摘The cutting burr is one of the common phenomena occurring in metal cutting.In this paper,the forming processes,main effect factors and change law of the cutting direction burr in orthogonal cutting have been studied and related theories are analyzed based on the cutting experiments.The result shows that:(1)the forming processes of cutting direction burr consist of normal cutting,flexure deformation of end surface of workpiece,plastic effect,continuous cutting and shear break separating in orthogonal cutting;(2)a new phenomenon is found that cutting direction burr is formed with the shear break separation of the chip and workpiece machined surfaces;(3)the size of cutting direction burr varies with workpiece materials,cutting parameters and geometric parameters of the cutting tool.
文摘We present a two-photon three-dimensional multiparty quantum secret sharing scheme.The secret messagesare encoded by performing local operations.This is different from those quantum secret sharing protocols that all sharersmust make a state measurement.The merit of our protocol is the high capacity.
