AIM:Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia.METHODS:Submandibular glands were isolated from male Wistar rats under system...AIM:Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia.METHODS:Submandibular glands were isolated from male Wistar rats under systemic anesthesia with pentobarbital sodium.The artery was cannulated and vascularly perfused at a constant rate.The excretory duct was also cannulated and the secreted saliva was weighed in a cup on an electronic balance.The weight of the accumulated saliva was measured every 3 s and the salivary flow rate was calculated.In addition,the arterio-venous difference in the partial oxygen pressure was measured as an indicator of oxygen consumption.In order to assess the mechanism involved in Dansheninduced fluid secretion,either ouabain(an inhibitor of Na+/K+ ATPase) or bumetanide(an inhibitor of NKCC1) was additionally applied during the Danshen stimulation.In order to examine the involvement of the main membrane receptors,atropine was added to block the M3 muscarinic receptors,or phentolamine was added to block the α1 adrenergic receptors.In order to examine the requirement for extracellular Ca2+,Danshen was applied during the perfusion with nominal Ca2+ free solution.RESULTS:Although Danshen induced salivary fluid secretion,88.7 ± 12.8 μL/g-min,n = 9,(the highest value around 20 min from start of DS perfusion was significantly high vs 32.5 ± 5.3 μL/g-min by carbamylcholine,P = 0.00093 by t-test) in the submandibular glands,the time course of that secretion differed from that induced by carbamylcholine.There was a latency associated with the fluid secretion induced by Danshen,followed by a gradual increasein the secretion to its highest value,which was in turn followed by a slow decline to a near zero level.The application of either ouabain or bumetanide inhibited the fluid secretion by 85% or 93%,and suppressed the oxygen consumption by 49% or 66%,respectively.These results indicated that Danshen activates Na+/K+ ATPase and NKCC1 to maintain Cl- release and K+ release for fluid secretion.Neither atropine or phentolamine inhibited the fluid secretion induced by Danshen(263% ± 63% vs 309% ± 45%,227% ± 63% vs 309% ± 45%,P = 0.899,0.626 > 0.05 respectively,by ANOVA).Accordingly,Danshen does not bind with M3 or α1 receptors.These characteristics suggested that the mechanism involved in DS-induced salivary fluid secretion could be different from that induced by carbamylcholine.Carbamylcholine activates the M3 receptor to release inositol trisphosphate(IP3) and quickly releases Ca2+ from the calcium stores.The elevation of [Ca2+]i induces chloride release and quick osmosis,resulting in an onset of fluid secretion.An increase in [Ca2+]i is essential for the activation of the luminal Cl- and basolateral K+ channels.The nominal removal of extracellular Ca2+ totally abolished the fluid secretion induced by Danshen(1.8 ± 0.8 μL/g-min vs 101.9 ± 17.2 μL/g-min,P = 0.00023 < 0.01,by t-test),suggesting the involvement of Ca2+ in the activation of these channels.Therefore,IP3-store Ca2+ release signalling may not be involved in the secretion induced by Danshen,but rather,there may be a distinct signalling process.CONCLUSION:The present findings suggest that Danshen can be used in the treatment of xerostomia,to avoid the systemic side effects associated with muscarinic drugs.展开更多
Dual-frequency aegon discharge at 100 m Torr is modeled with a 2-D fluid model in this study. The plate gap of the system is 20 ram, and discharges are modeled at High Frequency （HF） 40 MHz, 60 MHz, 80 MHz, Low Freq...Dual-frequency aegon discharge at 100 m Torr is modeled with a 2-D fluid model in this study. The plate gap of the system is 20 ram, and discharges are modeled at High Frequency （HF） 40 MHz, 60 MHz, 80 MHz, Low Frequency （LF） 2 MHz, 5 MHz, 10 MHz, low-frequency voltage 50 V, 75 V, 100 V and high-frequency voltage 200 V, respectively. The spatial distribution of electron density and ion density and the periodic evolution of instantaneous electric potential in bulk plasma and sheath are discussed. The numerical results show that plasma density increases with HFs and LFs and LF voltage, while HFs has more effect on the density. It is concluded that improving the ratio of HFs/LFs and increasing LF voltages is a method to gain high density and high ion bombardment energy simultaneously based on the analysis of electric potential distribution.展开更多
In this paper, a novel algorithm based on disturbed fluid and trajectory propagation is developed to solve the three-dimensional（3-D） path planning problem of unmanned aerial vehicle（UAV） in static environment.Fir...In this paper, a novel algorithm based on disturbed fluid and trajectory propagation is developed to solve the three-dimensional（3-D） path planning problem of unmanned aerial vehicle（UAV） in static environment.Firstly, inspired by the phenomenon of streamlines avoiding obstacles, the algorithm based on disturbed fluid is developed and broadened.The effect of obstacles on original fluid field is quantified by the perturbation matrix, where the tangential matrix is first introduced.By modifying the original flow field, the modified one is then obtained, where the streamlines can be regarded as planned paths.And the path proves to avoid all obstacles smoothly and swiftly, follow the shape of obstacles effectively and reach the destination eventually.Then, by considering the kinematics and dynamics equations of UAV, the method called trajectory propagation is adopted to judge the feasibility of the path.If the planned path is unfeasible, repulsive and tangential parameters in the perturbation matrix will be adjusted adaptively based on the resolved state variables of UAV.In most cases, a flyable path can be obtained eventually.Simulation results demonstrate the effectiveness of this method.展开更多
The transport of fluid, nutrients, and signaling molecules in the bone lacunar-canalicular system （LCS） is critical for osteocyte survival and function. We have applied the fluorescence recovery after photobleaching...The transport of fluid, nutrients, and signaling molecules in the bone lacunar-canalicular system （LCS） is critical for osteocyte survival and function. We have applied the fluorescence recovery after photobleaching （FRAP） approach to quantify load-induced fluid and solute transport in the LCS in situ, but the measurements were limited to cortical regions 30-50 μm underneath the periosteum due to the constrains of laser penetration. With this work, we aimed to expand our understanding of load-induced fluid and solute transport in both trabecular and cortical bone using a multiscaled image-based finite element analysis （FEA） approach. An intact murine tibia was first re-constructed from microCT images into a three-dimensional （3D） linear elastic FEA model, and the matrix deformations at various locations were calculated under axial loading. A segment of the above 3D model was then imported to the biphasic poroelasticity analysis platform （FEBio） to predict load-induced fluid pressure fields, and interstitial solute/fluid flows through LCS in both cortical and trabecular regions. Further, secondary flow effects such as the shear stress and/or drag force acting on osteocytes, the presumed mechano-sensors in bone, were derived using the previously developed ultrastructural model of Brinkman flow in the canaliculi. The material properties assumed in the FEA models were validated against previously obtained strain and FRAP transport data measured on the cortical cortex. Our results demonstrated the feasibility of this computational approach in estimating the fluid flux in the LCS and the cellular stimulation forces （shear and drag forces） for osteocytes in any cortical and trabecular bone locations, allowing further studies of how the activation of osteocytes correlates with in vivo functional bone formation. The study provides a promising platform to reveal potential cellular mechanisms underlying the anabolic power of exercises and physical activities in treating patients with skeletal deficiencies.展开更多
The Gaoshan gold-silver deposit, located between the Yuyao-Lishui Fault and Jiangshan- Shaoxing fault in Longquan Area, occurs in the Suichang-Longquan gold-silver polymetallic metallogenic belt. This study conducted ...The Gaoshan gold-silver deposit, located between the Yuyao-Lishui Fault and Jiangshan- Shaoxing fault in Longquan Area, occurs in the Suichang-Longquan gold-silver polymetallic metallogenic belt. This study conducted an investigation for ore-forming fluids using microthermometry, D-O isotope and trace element. The results show that two types of fluid inclusions involved into the formation of the deposit are pure liquid phase and gas-liquid phase aqueous inclusions. The homogenization temperature and salinity of major mineralization phase ranges from 156~C to 236~C （average 200~C） and 0.35% to 8.68% （NaCleqv） （average 3.68%）, respectively, indicating that the ore-forming fluid is characteristic of low temperature and low salinity. The ore- forming pressure ranges between in 118.02 to 232.13＂105 pa, and it is estabmiated that the ore- forming depth ranges from 0.39 to 0.77 km, indicating it is a hypabyssal deposit in genesis. The low rare earth elements content in pyrites, widely developed fluorite in late ore-forming stage and lack of chlorargyrite （AgCI）, indicates that the ore-forming fluid is rich in F rather than CI. The ratios of Y/ Ho, Zr/Hf and Nb/Ta of between different samples have little difference, indicating that the later hydrothermal activities had no effects on the former hydrothermal fluid. The chondrite-normalized REE patterns of pyrites from country rocks and ore veins are basically identical, with the characteristics of light REE enrichment and negative Eu anomalies, implying that the ore-forming fluid was oxidative and derived partly from the country rocks. The JD and jlSo of fluid inclusions in quartz formed during the main metallogenic stage range from -105%o to -69 %0 and -6.01%o to -3.81%o, respectively. The D-O isotopic diagram shows that the metallogenic fluid is characterized by the mixing of formation water and meteoric water, without involvement of magmatic water. The geological and geochemical characteristics of the Gaoshan gold-silver deposit are similar to those of continental volcanic hydrothermal deposit, and could be assigned to the continental volcanic hydrothermal gold-silver deposit type.展开更多
Based on the renormalization group theory, a hydraulic torque converter 3 D turbulent single flow passage model is constructed and boundary condition is determined for analyzing the influence of the fluid field chara...Based on the renormalization group theory, a hydraulic torque converter 3 D turbulent single flow passage model is constructed and boundary condition is determined for analyzing the influence of the fluid field characteristic and parameters on the macroscopic model. Numerical simulation of the single fluid path is processed by computational fluid dynamics and the calculated results approach to experimental data well, and especially in low transmission ratio the torque and head results are more close to experimental data than the calculated results of beam theory. This shows that the appropriate ternary analysis method and reasonable assumption of boundary condition may analyze the flow field more precisely and predict the performance of torque converter more accurately.展开更多
基金Supported by Grants from The National Institute for Physiological Sciences and Graduate University for Advanced Studies
文摘AIM:Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia.METHODS:Submandibular glands were isolated from male Wistar rats under systemic anesthesia with pentobarbital sodium.The artery was cannulated and vascularly perfused at a constant rate.The excretory duct was also cannulated and the secreted saliva was weighed in a cup on an electronic balance.The weight of the accumulated saliva was measured every 3 s and the salivary flow rate was calculated.In addition,the arterio-venous difference in the partial oxygen pressure was measured as an indicator of oxygen consumption.In order to assess the mechanism involved in Dansheninduced fluid secretion,either ouabain(an inhibitor of Na+/K+ ATPase) or bumetanide(an inhibitor of NKCC1) was additionally applied during the Danshen stimulation.In order to examine the involvement of the main membrane receptors,atropine was added to block the M3 muscarinic receptors,or phentolamine was added to block the α1 adrenergic receptors.In order to examine the requirement for extracellular Ca2+,Danshen was applied during the perfusion with nominal Ca2+ free solution.RESULTS:Although Danshen induced salivary fluid secretion,88.7 ± 12.8 μL/g-min,n = 9,(the highest value around 20 min from start of DS perfusion was significantly high vs 32.5 ± 5.3 μL/g-min by carbamylcholine,P = 0.00093 by t-test) in the submandibular glands,the time course of that secretion differed from that induced by carbamylcholine.There was a latency associated with the fluid secretion induced by Danshen,followed by a gradual increasein the secretion to its highest value,which was in turn followed by a slow decline to a near zero level.The application of either ouabain or bumetanide inhibited the fluid secretion by 85% or 93%,and suppressed the oxygen consumption by 49% or 66%,respectively.These results indicated that Danshen activates Na+/K+ ATPase and NKCC1 to maintain Cl- release and K+ release for fluid secretion.Neither atropine or phentolamine inhibited the fluid secretion induced by Danshen(263% ± 63% vs 309% ± 45%,227% ± 63% vs 309% ± 45%,P = 0.899,0.626 > 0.05 respectively,by ANOVA).Accordingly,Danshen does not bind with M3 or α1 receptors.These characteristics suggested that the mechanism involved in DS-induced salivary fluid secretion could be different from that induced by carbamylcholine.Carbamylcholine activates the M3 receptor to release inositol trisphosphate(IP3) and quickly releases Ca2+ from the calcium stores.The elevation of [Ca2+]i induces chloride release and quick osmosis,resulting in an onset of fluid secretion.An increase in [Ca2+]i is essential for the activation of the luminal Cl- and basolateral K+ channels.The nominal removal of extracellular Ca2+ totally abolished the fluid secretion induced by Danshen(1.8 ± 0.8 μL/g-min vs 101.9 ± 17.2 μL/g-min,P = 0.00023 < 0.01,by t-test),suggesting the involvement of Ca2+ in the activation of these channels.Therefore,IP3-store Ca2+ release signalling may not be involved in the secretion induced by Danshen,but rather,there may be a distinct signalling process.CONCLUSION:The present findings suggest that Danshen can be used in the treatment of xerostomia,to avoid the systemic side effects associated with muscarinic drugs.
文摘Dual-frequency aegon discharge at 100 m Torr is modeled with a 2-D fluid model in this study. The plate gap of the system is 20 ram, and discharges are modeled at High Frequency （HF） 40 MHz, 60 MHz, 80 MHz, Low Frequency （LF） 2 MHz, 5 MHz, 10 MHz, low-frequency voltage 50 V, 75 V, 100 V and high-frequency voltage 200 V, respectively. The spatial distribution of electron density and ion density and the periodic evolution of instantaneous electric potential in bulk plasma and sheath are discussed. The numerical results show that plasma density increases with HFs and LFs and LF voltage, while HFs has more effect on the density. It is concluded that improving the ratio of HFs/LFs and increasing LF voltages is a method to gain high density and high ion bombardment energy simultaneously based on the analysis of electric potential distribution.
基金supported by the National Natural Science Foundation of China (No.61175084)the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (No.IRT13004)
文摘In this paper, a novel algorithm based on disturbed fluid and trajectory propagation is developed to solve the three-dimensional（3-D） path planning problem of unmanned aerial vehicle（UAV） in static environment.Firstly, inspired by the phenomenon of streamlines avoiding obstacles, the algorithm based on disturbed fluid is developed and broadened.The effect of obstacles on original fluid field is quantified by the perturbation matrix, where the tangential matrix is first introduced.By modifying the original flow field, the modified one is then obtained, where the streamlines can be regarded as planned paths.And the path proves to avoid all obstacles smoothly and swiftly, follow the shape of obstacles effectively and reach the destination eventually.Then, by considering the kinematics and dynamics equations of UAV, the method called trajectory propagation is adopted to judge the feasibility of the path.If the planned path is unfeasible, repulsive and tangential parameters in the perturbation matrix will be adjusted adaptively based on the resolved state variables of UAV.In most cases, a flyable path can be obtained eventually.Simulation results demonstrate the effectiveness of this method.
基金supported by grants from NIH (P30GM103333 and RO1AR054385 to LW)China CSC fellowship (to LF)DOD W81XWH-13-1-0148 (to XLL)
文摘The transport of fluid, nutrients, and signaling molecules in the bone lacunar-canalicular system （LCS） is critical for osteocyte survival and function. We have applied the fluorescence recovery after photobleaching （FRAP） approach to quantify load-induced fluid and solute transport in the LCS in situ, but the measurements were limited to cortical regions 30-50 μm underneath the periosteum due to the constrains of laser penetration. With this work, we aimed to expand our understanding of load-induced fluid and solute transport in both trabecular and cortical bone using a multiscaled image-based finite element analysis （FEA） approach. An intact murine tibia was first re-constructed from microCT images into a three-dimensional （3D） linear elastic FEA model, and the matrix deformations at various locations were calculated under axial loading. A segment of the above 3D model was then imported to the biphasic poroelasticity analysis platform （FEBio） to predict load-induced fluid pressure fields, and interstitial solute/fluid flows through LCS in both cortical and trabecular regions. Further, secondary flow effects such as the shear stress and/or drag force acting on osteocytes, the presumed mechano-sensors in bone, were derived using the previously developed ultrastructural model of Brinkman flow in the canaliculi. The material properties assumed in the FEA models were validated against previously obtained strain and FRAP transport data measured on the cortical cortex. Our results demonstrated the feasibility of this computational approach in estimating the fluid flux in the LCS and the cellular stimulation forces （shear and drag forces） for osteocytes in any cortical and trabecular bone locations, allowing further studies of how the activation of osteocytes correlates with in vivo functional bone formation. The study provides a promising platform to reveal potential cellular mechanisms underlying the anabolic power of exercises and physical activities in treating patients with skeletal deficiencies.
基金funded by “Preliminary Study On the Metallogenic Conditions and Prospecting Direction of Gold-Silver Deposits,Suichang-Longquan Area,Zhejiang(No.:YK1401)”“Summary and Research Project of the Mineral Geology of China by Mineral Type(Group)(No.:12120114039601)”+1 种基金“Research Project of the Metallogenic Regularity of the National Important Mineral Areas(No.:1212011121037)”“Comprehensive Research Project of China’s Mineral Geology and Regional Metallogenic Regularity(China’s Mineral Geology)(No.:1212011220369)”
文摘The Gaoshan gold-silver deposit, located between the Yuyao-Lishui Fault and Jiangshan- Shaoxing fault in Longquan Area, occurs in the Suichang-Longquan gold-silver polymetallic metallogenic belt. This study conducted an investigation for ore-forming fluids using microthermometry, D-O isotope and trace element. The results show that two types of fluid inclusions involved into the formation of the deposit are pure liquid phase and gas-liquid phase aqueous inclusions. The homogenization temperature and salinity of major mineralization phase ranges from 156~C to 236~C （average 200~C） and 0.35% to 8.68% （NaCleqv） （average 3.68%）, respectively, indicating that the ore-forming fluid is characteristic of low temperature and low salinity. The ore- forming pressure ranges between in 118.02 to 232.13＂105 pa, and it is estabmiated that the ore- forming depth ranges from 0.39 to 0.77 km, indicating it is a hypabyssal deposit in genesis. The low rare earth elements content in pyrites, widely developed fluorite in late ore-forming stage and lack of chlorargyrite （AgCI）, indicates that the ore-forming fluid is rich in F rather than CI. The ratios of Y/ Ho, Zr/Hf and Nb/Ta of between different samples have little difference, indicating that the later hydrothermal activities had no effects on the former hydrothermal fluid. The chondrite-normalized REE patterns of pyrites from country rocks and ore veins are basically identical, with the characteristics of light REE enrichment and negative Eu anomalies, implying that the ore-forming fluid was oxidative and derived partly from the country rocks. The JD and jlSo of fluid inclusions in quartz formed during the main metallogenic stage range from -105%o to -69 %0 and -6.01%o to -3.81%o, respectively. The D-O isotopic diagram shows that the metallogenic fluid is characterized by the mixing of formation water and meteoric water, without involvement of magmatic water. The geological and geochemical characteristics of the Gaoshan gold-silver deposit are similar to those of continental volcanic hydrothermal deposit, and could be assigned to the continental volcanic hydrothermal gold-silver deposit type.
文摘Based on the renormalization group theory, a hydraulic torque converter 3 D turbulent single flow passage model is constructed and boundary condition is determined for analyzing the influence of the fluid field characteristic and parameters on the macroscopic model. Numerical simulation of the single fluid path is processed by computational fluid dynamics and the calculated results approach to experimental data well, and especially in low transmission ratio the torque and head results are more close to experimental data than the calculated results of beam theory. This shows that the appropriate ternary analysis method and reasonable assumption of boundary condition may analyze the flow field more precisely and predict the performance of torque converter more accurately.
