This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference...This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference in the percentage of nucleated fibroblasts in the G0/G1 stage between serum concentrations of 0.3% and 0.4% (83.89% and 82.69%, respectively, P > 0.05) as well as between serum concentrations of 0.2% and 0.5% (76.95% and 75.46%, respectively, P > 0.05). The percentage of nucleated fibroblasts in the G0/G1 stage was highest at the concentration of 0.3% and lowest in the control group (83.89% vs. 62.67%, P 0.05). The beneficial effect of high confluence was confirmed by the large percentage of nucleated fibroblasts at the G0/G1 stage. The 60% confluency was significantly lower than the 80% and 100% confluency (73.44%, 86.63%, and 87.17%, respectively, P < 0.05). The results indicate that the goat fibroblast cycle synchronization is the most effective at the serum concentration of 0.3%, 72 hours of synchronization and 100% confluency.展开更多
In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town ...In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town of Zhenjiang. The specific research object is the runoff of the outfall of rainwater-sewage confluence in the area. On the basis of detecting and analyzing the water yield and water quality of the runoff of rainwater-sewage confluence a combined technology which contains four independent continuous processes for lowering pollution load was developed and system equipment was established and put into operation. The processing effects of the project were monitored and analyzed.The results show that the pollution control project of outfall runoff is efficient which decreases the pollution load including chemical oxygen demand COD total phosphorus TP suspended solids SS and ammonia-nitrogen NH3-N .As a result the water environment of the ancient canal is protected.展开更多
Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized co...Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence hydrodynamics.This study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by others.Four configurations with different bed discordance ratios were investigated.The results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression reduces.The bed elevation discordance also leads to the development of a large-scale structure in the lee of the step.Despite the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance ratio.It turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently.展开更多
Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of l...Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of liquid metal streams.The main filling-related defects are cold shut defects.To calculate the positions of casting defects,the characteristics of liquid metal confluences were analyzed.The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field,which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams.To distinguish small confluences from the main confluences,the concept of confluent scale was developed,which was used to filter the small confluences based on a threshold.The calculation process was demonstrated through the post-processing of numerical simulation.A "W" shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study.The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams.The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting.The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan.展开更多
AIM:To investigate injuries of anatomy variants of hepatic duct confluence during hepatobiliary surgery and their impact on morbidity and mortality of these procedures. An algorithmic approach for the management of th...AIM:To investigate injuries of anatomy variants of hepatic duct confluence during hepatobiliary surgery and their impact on morbidity and mortality of these procedures. An algorithmic approach for the management of these injuries is proposed. METHODS:During a 6-year period 234 patients who had undergone major hepatobiliary surgery were retrospectively reviewed in order to study postoperative bile leakage. Diagnostic workup included endoscopic and magnetic retrograde cholangiopancreatography (E/MRCP), scintigraphy and fistulography. RESULTS:Thirty (12.8%) patients who developed postoperative bile leaks were identified. Endoscopic stenting and percutaneous drainage were successful in 23 patients with bile leaks from the liver cut surface. In the rest seven patients with injuries of hepatic duct confluence, biliary variations were recognized and a stepwise therapeutic approach was considered. Conservative management was successful only in 2 patients. Volume of the liver remnant and functional liver reserve as well as local sepsis were used as criteria for either resection of the corresponding liver segment or construction of a biliary-enteric anastomosis. Two deaths occurred in this group of patients with hepatic duct confluence variants (mortality rate 28.5%). CONCLUSION:Management of major biliary fistulaethat are disconnected from the mainstream of the biliary tree and related to injury of variants of the hepatic duct confluence is extremely challenging. These patients have a grave prognosis and an early surgical procedure has to be considered.展开更多
In order to calculate the suspended sediment discharge of the flood debris flows into the main river,a small scale flume test was designed to simulate the process of confluence of Jiangjia Ravine and Xiangjiang River ...In order to calculate the suspended sediment discharge of the flood debris flows into the main river,a small scale flume test was designed to simulate the process of confluence of Jiangjia Ravine and Xiangjiang River in Yunnan province,China.By test observation and data analysis,suspended sediment discharge of Debris flow after its entry into the main river was found to have a close relation with the bulk density,the confluence angle of the Debris flow and the main river,the ratio between per unit width discharge of Debris flow and main river.Based on the measured and simulated results,and statistical analysis,an empirical formula was proposed for the suspended SDR(Sediment Delivery Ratio) of the main river after the confluence of Debris flow.Compared with the observed results of Debris flow in 2009,the error between the data calculated by the empirical formula and the monitored data is only about 10%.展开更多
Objective: To review our experience in and the re-sults of resecting liver tumors involving the hepatoca-val confluence under intermittent portal triad clam-ping (PTC).Methods: Sixty-eight consecutive patients with li...Objective: To review our experience in and the re-sults of resecting liver tumors involving the hepatoca-val confluence under intermittent portal triad clam-ping (PTC).Methods: Sixty-eight consecutive patients with livertumors involving the hepatocaval confluence under-went hepatectomies with liver parenchymal transec-tions under intermittent PTC.Results: All the tumors were successfully resected un-der PTC, except for one in which the infrahepatic in-ferior vena cava was concomitantly occluded in addi-tion to PTC. There was neither operative death noruncontrollable massive bleeding or air embolism oc-curred in our patients. The bleedings from the mainand short hepatic veins and right adrenal veins wereproperly managed during the operation, with a meanintraoperative blood loss of 1400 ml. Of the 68tumors resected, 65 were hepatocellular carcinomas(HCC). Their 1-, 2-, 3- and 4-year suvival rateswere 64.11%, 52. 82%, 44.90% and 36.98%, re-spectively, and the patients with HCC with capsulessurvived significantly longer than those with HCCwithout capsules.Conclusions: The liver tumors involving the hepato-caval confluence could be safely resected simply un-der PTC, without routine use of total hepatic vascu-lar exclusion. As for HCCs in this area, the tumorwith capsule is a better indicator for surgical resec-tion than that without capsule.展开更多
Also if rarely, hepatocellular carcinoma, cholangiocarcinoma, and metastatic carcinoma can invade the retrohepatic portion of the inferior vena cava (IVC), because of the proximity of this vessel to the liver.
FOSHAN is an ancient city endowed with a bountiful culture.Located in the heartland of the vibrant Pearl River Delta,Foshan is west of Guangzhou,the capital of Guangdong Province,and gazes upon Hong Kong and Macao fro...FOSHAN is an ancient city endowed with a bountiful culture.Located in the heartland of the vibrant Pearl River Delta,Foshan is west of Guangzhou,the capital of Guangdong Province,and gazes upon Hong Kong and Macao from the north.For centuries,Foshan has been the economic and trade center in this region,and known for its high-quality ceramic products throughout the country.In modern times,it has witnessed a growth展开更多
Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox process.This outstanding capability enables the direct conversion of non-functionalized substrates into r...Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox process.This outstanding capability enables the direct conversion of non-functionalized substrates into reactive intermediates by utilizing easily accessible starting materials, eliminating the need for preliminary functionalization procedures and allowing for unconventional bond activations.展开更多
Abundant solid materials were formed as a result of landslide and collapse due to Wenchuan earthquake.The solid source around mountains would form a debris flow when appropriate rain condition occurs.Such a debris flo...Abundant solid materials were formed as a result of landslide and collapse due to Wenchuan earthquake.The solid source around mountains would form a debris flow when appropriate rain condition occurs.Such a debris flow is structurally very large and strong,and the river flow can hardly wash away the deposit when the debris flow enters into the mainstream.As a result,the deposit on the river bed due to debris flow will cause a series of hazards.Based on the previous researches and relevant data,this paper simplified the interaction between debris flow and current of the main river,and adopted the finite element characteristic-based-split algorithm which is favorable to the stabilization of dealing with the convection.Finally,the numerical model of the confluence of debris flow deposit and main river was developed,and the deposit progress of the mega-debris flow from Wenjiagou in Mianyuan river was reproduced.Furthermore,the influence of the deposit on the flow route of the main river,and distribution of velocity and water depth were analyzed.The results showed that the simulation deposit terrain qualitatively agreed with the field data through comparison,including the deposit area and depth distribution.Furthermore,the improvement of the model in future was discussed.展开更多
The hydraulic characteristics at the confluence reach of river and lake are influenced by multiple factors such as inflow,topography and vegetation resistance,and are very complicated.In this article,the confluence re...The hydraulic characteristics at the confluence reach of river and lake are influenced by multiple factors such as inflow,topography and vegetation resistance,and are very complicated.In this article,the confluence reach of Yangtze River and Dong-ting Lake is selected as a special example and a hybrid model is built to study the flow at this confluence,with the consideration of the interactions between aquatic vegetation and flow.Validation tests and calculations show that the model is effective and highly accurate.The simulations show that the separation levee at the confluence reach may change the discharge capacity in the flood plain,which would be enhanced in the upper reach of the levee,hardly changed in the middle reach and reduced at the lower place.Moreover,the separation levee also limits the water exchange between the Yangtze River and Dong-ting Lake.展开更多
Confluences act as critical nodes in a river system.They affect hydrodynamics,sediment transport,bed morphology,and eco-hydraulics of the river system.Convergence of streams produces the complex mechanism of flow mome...Confluences act as critical nodes in a river system.They affect hydrodynamics,sediment transport,bed morphology,and eco-hydraulics of the river system.Convergence of streams produces the complex mechanism of flow momentum and mass mixing which may affect the aquatic environment locally and even lasting for a long distance downstream.The confluence creates a hotspot for the river system’s ecological change,which usually leads to changes in water temperature,suspended-sediment load,bed material,nutrient concentrations,water chemistry,and organic-matter content.Hence,the dynamics of river confluences are very complex and have critical effects on river system’s water environment and ecology.For this reason,a review summarizing turbulent flow,sediment transport,morphological-dynamics,mixing processes,and their effects on the ecology of the aquatic environment at river confluences is in order.A future research agenda and opportunities pertinent to river confluence are vitally emphasized as a multidisciplinary research topic.展开更多
The distribution of the phosphorus(P) adsorption in a bed sediment at channel confluences is an important issue for understanding the transport of contaminants in channel networks. In this study, the flow structure ...The distribution of the phosphorus(P) adsorption in a bed sediment at channel confluences is an important issue for understanding the transport of contaminants in channel networks. In this study, the flow structure and its effect on the P distribution in the bed sediment were investigated in a 90° confluence flume. It is shown that the P adsorption amount in the sediment varies significantly in different hydrodynamic zones. The P adsorption amount is high in the flow separation zone where the horizontal velocity of the flow is very small, and it is low in the maximum velocity zone where the flow velocity reaches a maximum. The low P adsorption amount is observed in the downstream portion of the distorted shear layer, while the P enrichment is found in the upstream portion, as is related to the significant downwelling flow in this zone. Thus, the flow structure, especially, the flow velocity, has a significant effect on the distribution of the P adsorption in the bed sediment at the channel confluences.展开更多
In this paper, we analyze the bifurcation and the confluence of the Pacific western boundary currents by an analytical approach. Applying the conservation law, the geostrophic balance relation and the Bernoulli integr...In this paper, we analyze the bifurcation and the confluence of the Pacific western boundary currents by an analytical approach. Applying the conservation law, the geostrophic balance relation and the Bernoulli integral to a reduced gravity model, we get a quantitative relation for the outflow and the inflow, and establish the related formulae for the width and the veering angle of offshore currents under the inflow condition. Furthermore, a comparison between the volume transport based on the observation data and the analytical value for the Pacific western boundary currents is presented, which validates the theoretical analysis.展开更多
Coalescence of traditional medicine Ayurveda and in silico technology is a rigor for supplementary development of future-ready effective traditional medicine. Ayurveda is a popular traditional medicine in South Asia, ...Coalescence of traditional medicine Ayurveda and in silico technology is a rigor for supplementary development of future-ready effective traditional medicine. Ayurveda is a popular traditional medicine in South Asia, emanating worldwide for the treatment of metabolic disorders and chronic illness. Techniques of in silico biology are not much explored for the investigation of a variety of bioactive phytochemicals of Ayurvedic herbs. Drug repurposing, reverse pharmacology, and polypharmacology in Ayurveda are areas in silico explorations that are needed to understand the rich repertoire of herbs, minerals, herbo-minerals, and assorted Ayurvedic formulations. This review emphasizes exploring the concept of Ayurveda with in silico approaches and the need for Ayurinformatics studies. It also provides an overview of in silico studies done on phytoconstituents of some important Ayurvedic plants, the utility of in silico studies in Ayurvedic phytoconstituents/formulations, limitations/challenges, and prospects of in silico studies in Ayurveda. This article discusses the convergence of in silico work, especially in the least explored field of Ayurveda. The focused coalesce of these two domains could present a predictive combinatorial platform to enhance translational research magnitude. In nutshell, it could provide new insight into an Ayurvedic drug discovery involving an in silico approach that could not only alleviate the process of traditional medicine research but also enhance its effectiveness in addressing health care.展开更多
For the study of the effects of partially non-submerged rigid vegetation on the free-surface confluence flow in a curved open channel,a numerical simulation is carried out by using the Volume of Fluid model combined w...For the study of the effects of partially non-submerged rigid vegetation on the free-surface confluence flow in a curved open channel,a numerical simulation is carried out by using the Volume of Fluid model combined with the porous media model with the software OpenFOAM.The model is first validated by using available experimental measurement data with a good agreement.Then,the characteristics of the separation zone generated by the centrifugal forces and the confluence flow are analyzed.Due to the resistance created by the vegetation,the velocities in the separation zone are more chaotic and the separation zone becomes smaller and more irregular.The reduction of the separation zone area of the vegetated flow in the convex bank is more significant than that in the concave bank.The velocities in the vegetated region become much smaller and remains so in the downstream flow after the vegetation region.Meanwhile,the vegetation compresses and divides the circulations in the flow area,rebuilding a structure with smaller circulations in the main flow and unclear circulations in the vegetation region.In addition,the bed wall shear stresses are significantly smaller in the vegetation region and the separation zone compared to the non-vegetated flow.This implies that the vegetation can have the effect of protecting the river bed from erosion.展开更多
Generally speaking,confluence property is not preserved when Term Rewriting Systems(TRSs) are combined,even if they are canonical.In this paper we give some sufficient conditions for ensuring the confluence property o...Generally speaking,confluence property is not preserved when Term Rewriting Systems(TRSs) are combined,even if they are canonical.In this paper we give some sufficient conditions for ensuring the confluence property of combined left-linear,overlapping TRSs.展开更多
The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion an...The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion and damage during the growth stage,which brings serious problems to the restoration of grass in the early stage.Therefore,effects of coir geotextile and geocell on EG erosion under four confluence intensities were researched in this study.Results of the simulated water discharge erosion test showed that when the confluence strength was less than 30 L/min,geocell and coir geotextile had a good effect on controlling EG erosion,and sediment yield of geocell and coir geotextile was reduced by 25.95%–37.82%and 73.73%–88.96%,respectively.However,when confluence intensity increased to 40 L/min,protective effect of coir geotextile decreased,and sediment yield rate increased sharply by 189.03%.When confluence intensity increased to 50 L/min,the protective effect of coir geotextile was lost.On the other hand,geocell showed that the greater the flow rate,the better the protective effect.In addition,with the increase in confluence intensity,erosion pattern of coir geotextile developed from sheet erosion to intermittent fall and then to completion of main rill,and the protective effect was gradually weakened.In contrast,the protective effect of EG under geocell was gradually enhanced from the continuous rill to the intermittent rill and finally to the intermittent fall.This study shows that coir geotextile and geocell can prevent EG erosion,and the effect of geocell is better than that of coir geotextile on the surface of EG.展开更多
Since the specifications of most of the existing context-sensitive graph grammars tend to be either too intricate or not intuitive, a novel context-sensitive graph grammar formalism, called context-attributed graph gr...Since the specifications of most of the existing context-sensitive graph grammars tend to be either too intricate or not intuitive, a novel context-sensitive graph grammar formalism, called context-attributed graph grammar(CAGG), is proposed. In order to resolve the embedding problem, context information of a graph production in the CAGG is represented in the form of context attributes of the nodes involved. Moreover, several properties of a set of confluent CAGG productions are characterized, and then an algorithm based on them is developed to decide whether or not a set of productions is confluent, which provides the foundation for the design of efficient parsing algorithms. It can also be shown through the comparison of CAGG with several typical context-sensitive graph grammars that CAGG is more succinct and, at the same time, more intuitive than the others, making it more suitably and effortlessly applicable to the specification of visual languages.展开更多
文摘This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference in the percentage of nucleated fibroblasts in the G0/G1 stage between serum concentrations of 0.3% and 0.4% (83.89% and 82.69%, respectively, P > 0.05) as well as between serum concentrations of 0.2% and 0.5% (76.95% and 75.46%, respectively, P > 0.05). The percentage of nucleated fibroblasts in the G0/G1 stage was highest at the concentration of 0.3% and lowest in the control group (83.89% vs. 62.67%, P 0.05). The beneficial effect of high confluence was confirmed by the large percentage of nucleated fibroblasts at the G0/G1 stage. The 60% confluency was significantly lower than the 80% and 100% confluency (73.44%, 86.63%, and 87.17%, respectively, P < 0.05). The results indicate that the goat fibroblast cycle synchronization is the most effective at the serum concentration of 0.3%, 72 hours of synchronization and 100% confluency.
基金The National Science and Technology Major Project of China(No.2008ZX07317-001)
文摘In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town of Zhenjiang. The specific research object is the runoff of the outfall of rainwater-sewage confluence in the area. On the basis of detecting and analyzing the water yield and water quality of the runoff of rainwater-sewage confluence a combined technology which contains four independent continuous processes for lowering pollution load was developed and system equipment was established and put into operation. The processing effects of the project were monitored and analyzed.The results show that the pollution control project of outfall runoff is efficient which decreases the pollution load including chemical oxygen demand COD total phosphorus TP suspended solids SS and ammonia-nitrogen NH3-N .As a result the water environment of the ancient canal is protected.
文摘Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence hydrodynamics.This study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by others.Four configurations with different bed discordance ratios were investigated.The results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression reduces.The bed elevation discordance also leads to the development of a large-scale structure in the lee of the step.Despite the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance ratio.It turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently.
基金supported by the National Key Research and Development Program of China(Nos.2020YFB2008300 and 2020YFB2008302)the Program of Key Research and Development Program of Guangdong Province(No.2019B090921001)。
文摘Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of liquid metal streams.The main filling-related defects are cold shut defects.To calculate the positions of casting defects,the characteristics of liquid metal confluences were analyzed.The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field,which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams.To distinguish small confluences from the main confluences,the concept of confluent scale was developed,which was used to filter the small confluences based on a threshold.The calculation process was demonstrated through the post-processing of numerical simulation.A "W" shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study.The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams.The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting.The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan.
文摘AIM:To investigate injuries of anatomy variants of hepatic duct confluence during hepatobiliary surgery and their impact on morbidity and mortality of these procedures. An algorithmic approach for the management of these injuries is proposed. METHODS:During a 6-year period 234 patients who had undergone major hepatobiliary surgery were retrospectively reviewed in order to study postoperative bile leakage. Diagnostic workup included endoscopic and magnetic retrograde cholangiopancreatography (E/MRCP), scintigraphy and fistulography. RESULTS:Thirty (12.8%) patients who developed postoperative bile leaks were identified. Endoscopic stenting and percutaneous drainage were successful in 23 patients with bile leaks from the liver cut surface. In the rest seven patients with injuries of hepatic duct confluence, biliary variations were recognized and a stepwise therapeutic approach was considered. Conservative management was successful only in 2 patients. Volume of the liver remnant and functional liver reserve as well as local sepsis were used as criteria for either resection of the corresponding liver segment or construction of a biliary-enteric anastomosis. Two deaths occurred in this group of patients with hepatic duct confluence variants (mortality rate 28.5%). CONCLUSION:Management of major biliary fistulaethat are disconnected from the mainstream of the biliary tree and related to injury of variants of the hepatic duct confluence is extremely challenging. These patients have a grave prognosis and an early surgical procedure has to be considered.
基金supported by the Key Research Program of the Chinese Academy ofSciences (Grant No.KZZD-EW-05-01)the National Natural Science Foundation of China(Grant No.40871024)
文摘In order to calculate the suspended sediment discharge of the flood debris flows into the main river,a small scale flume test was designed to simulate the process of confluence of Jiangjia Ravine and Xiangjiang River in Yunnan province,China.By test observation and data analysis,suspended sediment discharge of Debris flow after its entry into the main river was found to have a close relation with the bulk density,the confluence angle of the Debris flow and the main river,the ratio between per unit width discharge of Debris flow and main river.Based on the measured and simulated results,and statistical analysis,an empirical formula was proposed for the suspended SDR(Sediment Delivery Ratio) of the main river after the confluence of Debris flow.Compared with the observed results of Debris flow in 2009,the error between the data calculated by the empirical formula and the monitored data is only about 10%.
文摘Objective: To review our experience in and the re-sults of resecting liver tumors involving the hepatoca-val confluence under intermittent portal triad clam-ping (PTC).Methods: Sixty-eight consecutive patients with livertumors involving the hepatocaval confluence under-went hepatectomies with liver parenchymal transec-tions under intermittent PTC.Results: All the tumors were successfully resected un-der PTC, except for one in which the infrahepatic in-ferior vena cava was concomitantly occluded in addi-tion to PTC. There was neither operative death noruncontrollable massive bleeding or air embolism oc-curred in our patients. The bleedings from the mainand short hepatic veins and right adrenal veins wereproperly managed during the operation, with a meanintraoperative blood loss of 1400 ml. Of the 68tumors resected, 65 were hepatocellular carcinomas(HCC). Their 1-, 2-, 3- and 4-year suvival rateswere 64.11%, 52. 82%, 44.90% and 36.98%, re-spectively, and the patients with HCC with capsulessurvived significantly longer than those with HCCwithout capsules.Conclusions: The liver tumors involving the hepato-caval confluence could be safely resected simply un-der PTC, without routine use of total hepatic vascu-lar exclusion. As for HCCs in this area, the tumorwith capsule is a better indicator for surgical resec-tion than that without capsule.
文摘Also if rarely, hepatocellular carcinoma, cholangiocarcinoma, and metastatic carcinoma can invade the retrohepatic portion of the inferior vena cava (IVC), because of the proximity of this vessel to the liver.
文摘FOSHAN is an ancient city endowed with a bountiful culture.Located in the heartland of the vibrant Pearl River Delta,Foshan is west of Guangzhou,the capital of Guangdong Province,and gazes upon Hong Kong and Macao from the north.For centuries,Foshan has been the economic and trade center in this region,and known for its high-quality ceramic products throughout the country.In modern times,it has witnessed a growth
基金supported by the National Natural Science Foundation of China(21971227,22222113)CAS Project for Young Scientists in Basic Research(YSBR-054)+1 种基金the Fundamental Research Funds for the Central Universities(WK9990000090,WK9990000111)the Chinese Postdoctoral Science Foundation(2022TQ0324,2023M733376)。
文摘Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox process.This outstanding capability enables the direct conversion of non-functionalized substrates into reactive intermediates by utilizing easily accessible starting materials, eliminating the need for preliminary functionalization procedures and allowing for unconventional bond activations.
基金supported by the National Basic Research Program of China ("973" Project) (Grant No. 2011CB409903)the National Natural Science Foundation of China (Grant No. 50739002)
文摘Abundant solid materials were formed as a result of landslide and collapse due to Wenchuan earthquake.The solid source around mountains would form a debris flow when appropriate rain condition occurs.Such a debris flow is structurally very large and strong,and the river flow can hardly wash away the deposit when the debris flow enters into the mainstream.As a result,the deposit on the river bed due to debris flow will cause a series of hazards.Based on the previous researches and relevant data,this paper simplified the interaction between debris flow and current of the main river,and adopted the finite element characteristic-based-split algorithm which is favorable to the stabilization of dealing with the convection.Finally,the numerical model of the confluence of debris flow deposit and main river was developed,and the deposit progress of the mega-debris flow from Wenjiagou in Mianyuan river was reproduced.Furthermore,the influence of the deposit on the flow route of the main river,and distribution of velocity and water depth were analyzed.The results showed that the simulation deposit terrain qualitatively agreed with the field data through comparison,including the deposit area and depth distribution.Furthermore,the improvement of the model in future was discussed.
文摘The hydraulic characteristics at the confluence reach of river and lake are influenced by multiple factors such as inflow,topography and vegetation resistance,and are very complicated.In this article,the confluence reach of Yangtze River and Dong-ting Lake is selected as a special example and a hybrid model is built to study the flow at this confluence,with the consideration of the interactions between aquatic vegetation and flow.Validation tests and calculations show that the model is effective and highly accurate.The simulations show that the separation levee at the confluence reach may change the discharge capacity in the flood plain,which would be enhanced in the upper reach of the levee,hardly changed in the middle reach and reduced at the lower place.Moreover,the separation levee also limits the water exchange between the Yangtze River and Dong-ting Lake.
基金supported by the National Natural Science Foundation of China(Grant Nos.51779080,U2040205 and 52079044)supported by the Fundamental Research Funds for the Central Universities(Grant No.20195025712,B200202237)+1 种基金the 111 Project(Grant No.B17015)the Fok Ying Tung Education Foundation(Grant No.520013312)。
文摘Confluences act as critical nodes in a river system.They affect hydrodynamics,sediment transport,bed morphology,and eco-hydraulics of the river system.Convergence of streams produces the complex mechanism of flow momentum and mass mixing which may affect the aquatic environment locally and even lasting for a long distance downstream.The confluence creates a hotspot for the river system’s ecological change,which usually leads to changes in water temperature,suspended-sediment load,bed material,nutrient concentrations,water chemistry,and organic-matter content.Hence,the dynamics of river confluences are very complex and have critical effects on river system’s water environment and ecology.For this reason,a review summarizing turbulent flow,sediment transport,morphological-dynamics,mixing processes,and their effects on the ecology of the aquatic environment at river confluences is in order.A future research agenda and opportunities pertinent to river confluence are vitally emphasized as a multidisciplinary research topic.
基金Project supported by the National Natural Science Foundation of China(Grant No.51239003,51509073,201501007 and 51279046)
文摘The distribution of the phosphorus(P) adsorption in a bed sediment at channel confluences is an important issue for understanding the transport of contaminants in channel networks. In this study, the flow structure and its effect on the P distribution in the bed sediment were investigated in a 90° confluence flume. It is shown that the P adsorption amount in the sediment varies significantly in different hydrodynamic zones. The P adsorption amount is high in the flow separation zone where the horizontal velocity of the flow is very small, and it is low in the maximum velocity zone where the flow velocity reaches a maximum. The low P adsorption amount is observed in the downstream portion of the distorted shear layer, while the P enrichment is found in the upstream portion, as is related to the significant downwelling flow in this zone. Thus, the flow structure, especially, the flow velocity, has a significant effect on the distribution of the P adsorption in the bed sediment at the channel confluences.
基金supported by the National Natural Science Foundation of China(Grant Nos.40890154,10971016,91130020)
文摘In this paper, we analyze the bifurcation and the confluence of the Pacific western boundary currents by an analytical approach. Applying the conservation law, the geostrophic balance relation and the Bernoulli integral to a reduced gravity model, we get a quantitative relation for the outflow and the inflow, and establish the related formulae for the width and the veering angle of offshore currents under the inflow condition. Furthermore, a comparison between the volume transport based on the observation data and the analytical value for the Pacific western boundary currents is presented, which validates the theoretical analysis.
基金Indian National Science Academy for granting visiting scientist fellowship in 2019 for learning in silico studies in AyurvedaAIIA, New Delhi for laboratory support。
文摘Coalescence of traditional medicine Ayurveda and in silico technology is a rigor for supplementary development of future-ready effective traditional medicine. Ayurveda is a popular traditional medicine in South Asia, emanating worldwide for the treatment of metabolic disorders and chronic illness. Techniques of in silico biology are not much explored for the investigation of a variety of bioactive phytochemicals of Ayurvedic herbs. Drug repurposing, reverse pharmacology, and polypharmacology in Ayurveda are areas in silico explorations that are needed to understand the rich repertoire of herbs, minerals, herbo-minerals, and assorted Ayurvedic formulations. This review emphasizes exploring the concept of Ayurveda with in silico approaches and the need for Ayurinformatics studies. It also provides an overview of in silico studies done on phytoconstituents of some important Ayurvedic plants, the utility of in silico studies in Ayurvedic phytoconstituents/formulations, limitations/challenges, and prospects of in silico studies in Ayurveda. This article discusses the convergence of in silico work, especially in the least explored field of Ayurveda. The focused coalesce of these two domains could present a predictive combinatorial platform to enhance translational research magnitude. In nutshell, it could provide new insight into an Ayurvedic drug discovery involving an in silico approach that could not only alleviate the process of traditional medicine research but also enhance its effectiveness in addressing health care.
基金supported by the National Natural Science Foundation of China(Grant No.51739011)the National Key Research and Development Program of China(Grant No.2016YFC0402707-03).
文摘For the study of the effects of partially non-submerged rigid vegetation on the free-surface confluence flow in a curved open channel,a numerical simulation is carried out by using the Volume of Fluid model combined with the porous media model with the software OpenFOAM.The model is first validated by using available experimental measurement data with a good agreement.Then,the characteristics of the separation zone generated by the centrifugal forces and the confluence flow are analyzed.Due to the resistance created by the vegetation,the velocities in the separation zone are more chaotic and the separation zone becomes smaller and more irregular.The reduction of the separation zone area of the vegetated flow in the convex bank is more significant than that in the concave bank.The velocities in the vegetated region become much smaller and remains so in the downstream flow after the vegetation region.Meanwhile,the vegetation compresses and divides the circulations in the flow area,rebuilding a structure with smaller circulations in the main flow and unclear circulations in the vegetation region.In addition,the bed wall shear stresses are significantly smaller in the vegetation region and the separation zone compared to the non-vegetated flow.This implies that the vegetation can have the effect of protecting the river bed from erosion.
基金This work was supported partly by The National Science FoundationThe Ministry of Electronic Industries and High Technology Program under The National Commission of Science & Technology.
文摘Generally speaking,confluence property is not preserved when Term Rewriting Systems(TRSs) are combined,even if they are canonical.In this paper we give some sufficient conditions for ensuring the confluence property of combined left-linear,overlapping TRSs.
基金supported by the National Natural Science Foundation of China(41907047)the China Scholarship Council(202106515016)the Strategic International Collaboration of Scientific and Technological Innovation for the National Key Research and Development Plan(2016YFE0202900).
文摘The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion and damage during the growth stage,which brings serious problems to the restoration of grass in the early stage.Therefore,effects of coir geotextile and geocell on EG erosion under four confluence intensities were researched in this study.Results of the simulated water discharge erosion test showed that when the confluence strength was less than 30 L/min,geocell and coir geotextile had a good effect on controlling EG erosion,and sediment yield of geocell and coir geotextile was reduced by 25.95%–37.82%and 73.73%–88.96%,respectively.However,when confluence intensity increased to 40 L/min,protective effect of coir geotextile decreased,and sediment yield rate increased sharply by 189.03%.When confluence intensity increased to 50 L/min,the protective effect of coir geotextile was lost.On the other hand,geocell showed that the greater the flow rate,the better the protective effect.In addition,with the increase in confluence intensity,erosion pattern of coir geotextile developed from sheet erosion to intermittent fall and then to completion of main rill,and the protective effect was gradually weakened.In contrast,the protective effect of EG under geocell was gradually enhanced from the continuous rill to the intermittent rill and finally to the intermittent fall.This study shows that coir geotextile and geocell can prevent EG erosion,and the effect of geocell is better than that of coir geotextile on the surface of EG.
基金The National Natural Science Foundation of China(No.60571048,60673186,60736015)the National High Technology Researchand Development Program of China(863Program)(No.2007AA01Z178)
文摘Since the specifications of most of the existing context-sensitive graph grammars tend to be either too intricate or not intuitive, a novel context-sensitive graph grammar formalism, called context-attributed graph grammar(CAGG), is proposed. In order to resolve the embedding problem, context information of a graph production in the CAGG is represented in the form of context attributes of the nodes involved. Moreover, several properties of a set of confluent CAGG productions are characterized, and then an algorithm based on them is developed to decide whether or not a set of productions is confluent, which provides the foundation for the design of efficient parsing algorithms. It can also be shown through the comparison of CAGG with several typical context-sensitive graph grammars that CAGG is more succinct and, at the same time, more intuitive than the others, making it more suitably and effortlessly applicable to the specification of visual languages.