The CICG President Du Zhanyuan shares his insights about China-Europe talent cooperation.THE history of exchange between China and Europe is long and profound.Since the 16th century,European thinkers represented by Vo...The CICG President Du Zhanyuan shares his insights about China-Europe talent cooperation.THE history of exchange between China and Europe is long and profound.Since the 16th century,European thinkers represented by Voltaire,Bertrand Russell,and Arnold Joseph Toynbee have taken Chinese philosophy as a valuable complement to the European ideological system.China has also absorbed the ideas of European giants such as Adam Smith,Georg Wilhelm Friedrich Hegel,and Karl Marx for its transformation and progress.In recent years,exchanges and interactions between the two sides in various fields have become increasingly close.展开更多
BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on s...BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on safety and duration for metal stents in this setting is scarce.Due to limited access to endoscopic retrograde cholan-giopancreatography(ERCP)during the coronavirus disease 2019 pandemic in our centre,there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy.This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.METHODS Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query.Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records.The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months.Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for≤120 d or>120 d.RESULTS During the study period,a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course.In 33 ERCPs,the stent was removed or exchanged on a 3-month interval.No pancreatitis,perfor-ations or deaths occurred.Minor post-ERCP complications were similar between the 3-month(abdominal pain and intraductal migration)and 6-month(abdominal pain,septic shower and embedded stent)groups-6.1%vs 9.1%respectively,P=0.40.All strictures resolved at the end of the stenting course,but the stenting course was variable from 3 to 22 months.The recurrence rate for stenting courses lasting for up to 120 d was 71.4%and 21.4%for stenting courses of 121 d or over(P=0.03).There were 28 patients that were treated with a single ERCP with Kaffes,21 with removal after 120 d and 7 within 120 d.There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course(71.0%vs 10.0%,P=0.01).CONCLUSION Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.展开更多
The hidden world of amyloid biology has suddenly snapped into atomic-level focus,revealing over 80 amyloid protein fibrils,both pathogenic and functional.Unlike globular proteins,amyloid proteins flatten and stack int...The hidden world of amyloid biology has suddenly snapped into atomic-level focus,revealing over 80 amyloid protein fibrils,both pathogenic and functional.Unlike globular proteins,amyloid proteins flatten and stack into unbranched fibrils.Stranger still,a single protein sequence can adopt wildly different two-dimensional conformations,yielding distinct fibril polymorphs.展开更多
As 2024 comes to an end,the pickup in consumption and robust growth in a range of sectors have bolstered confidence that the Chinese economy is right on track to meet the preset growth rate of around five percent.Bene...As 2024 comes to an end,the pickup in consumption and robust growth in a range of sectors have bolstered confidence that the Chinese economy is right on track to meet the preset growth rate of around five percent.Benefiting from a flurry of consumption-stimulating policies and measures,China’s online retail sales surpassed RMB 14 trillion in the January-November period,a year-on-year increase of 7.4 percent.Imports and exports maintained steady growth,climbing by 4.9 percent year-on-year in renminbi terms.Value-added industrial output also expanded 5.8 percent year-on-year.The volume of express delivery parcels reached a new high of 150 billion and is expected to grow higher still given the new-year festivities ahead.展开更多
The two major challenges in industrial enzymatic catalysis are the limited number of chemical reaction types that are catalyzed by enzymes and the instability of enzymes under harsh conditions in industrial catalysis....The two major challenges in industrial enzymatic catalysis are the limited number of chemical reaction types that are catalyzed by enzymes and the instability of enzymes under harsh conditions in industrial catalysis.Expanding enzyme catalysis to a larger substrate scope and greater variety of chemical reactions and tuning the microenvironment surrounding enzyme molecules to achieve high enzyme performance are urgently needed.In this account,we focus on our efforts using the de novo approach to synthesis hybrid enzyme catalysts that can address these two challenges and the structure-function relationship is discussed to reveal the principles of designing hybrid enzyme catalysts.We hope that this account will promote further efforts toward fundamental research and wide applications of designed enzyme hybrid catalysts for expanding biocatalysis.展开更多
Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During rang...Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During range expansion, native species also encounter many new plant competitors. Thus, allelochemicals from native expanding species may also be more novel and allelopathic than those from non-expanding species to other plant competitors in the expanded range. We test this hypothesis using the native expanding Merremia boisiana and its non-expanding congener M. vitifolia in year 2012 inthe expanded range inHainan. In petridish bioassays, we found that aqueous extracts of M. boisiana leaves were often less inhibitory or more stimulatory to seed germination and seedling growth of five vegetable species than those of M. vitifolia leaves. In pot culture, we also found that aqueous leaf extracts of the two congeners could both inhibit the growth of a naturally co-occurring plant Paederia scanden, but their effects did not differ from each other. These results indicate that while allelopathy may contribute to the competitive ability of M. boisiana, it may not act as a novel weapon explaining its success in the expanded range in Hainan.展开更多
On the basis of defining the concept of "immiserizing growth in expanding economies",through analysing the status quo of economy in China's rural areas in the new era,this paper aims to find out the fact...On the basis of defining the concept of "immiserizing growth in expanding economies",through analysing the status quo of economy in China's rural areas in the new era,this paper aims to find out the factors responsible for economic weakness of China's rural residents.It analyses the impact of market consuming economy on growth economy,and points out the phenomenon of "immiserizing growth in expanding economies" which may be triggered by China's rapid rural economic growth as follows:first,the income disparity between urban and rural residents increases ceaselessly,the commodity prices continuously soar,and the rural residents' market consuming capacity is short;second,the wealth concentrates highly and the majority of farmers' income is low.Thus we put forward the countermeasures and proposals for preventing "immiserizing growth in expanding economies" in rural areas as follows:we should reform household registration system so that the rural residents have the right to migrate freely,and farmers' status is promoted;we should coordinate urban-rural development,strengthen agriculture and rural infrastructure building and achieve impartial allocation of public resources;we should carry out redistribution on income scientifically and effectively,consolidate rural social security system,bridge urban-rural income gap,transform the comparative advantage into competitive advantage,so as to circumvent "immiserizing growth in expanding economies".展开更多
In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homot...In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homotopy analysis method (HAM) is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail.展开更多
A one-dimensional theoretical model was adopted in this paper to describe and analyze the flow in an expanding RBCC(rocket based combined cycle)duct.It can be concluded that the expanding angle,heating amount and dist...A one-dimensional theoretical model was adopted in this paper to describe and analyze the flow in an expanding RBCC(rocket based combined cycle)duct.It can be concluded that the expanding angle,heating amount and distribution of heating play crucial roles on the thermal choking.They mainly influence the acceleration of flow,the position of choking throat and the total pressure loss.In order to fulfill the transition of subsonic flow to supersonic flow in the expanding RBCC duct,the heating amount has to change from a bigger value to a smaller one along the duct.When the thermal choking occurs in the RBCC duct,the moderate expanding angle,proper heating amount and distribution of heating are necessary for the best performance of RBCC combustor.Adopting the RBCC duct with smaller expanding angles anterior and bigger expanding angles posterior has positive effects on the thermal choking and flexibility of selecting heating method,and can restrain the negative effect of the combustion on the inlet also.展开更多
The introduction of laparoscopic procedures is one of the milestones of surgical innovation over the past few decades. The advantages of minimally invasive approach have been gradually accepted owing to its less posto...The introduction of laparoscopic procedures is one of the milestones of surgical innovation over the past few decades. The advantages of minimally invasive approach have been gradually accepted owing to its less postoperative pain, reduced morbidity and faster recovery. Also, since the introduction of laparoscopic approach of liver surgery in 1955 (1), the benefit of the procedure had long been questioned but expected.展开更多
The flow of a micropolar fluid in a semi-porous channel with an expanding or contracting wall is investigated. The governing equations are reduced to ordinary ones by using similar transformations. To get the analytic...The flow of a micropolar fluid in a semi-porous channel with an expanding or contracting wall is investigated. The governing equations are reduced to ordinary ones by using similar transformations. To get the analytic solution to the problem, the homotopy analysis method (HAM) is employed to obtain the expressions for velocity fields. Graphs are sketched and discussed for various parameters, especially the effect of the expansion ratio on velocity and micro-rotation fields.展开更多
BACKGROUND: Liver transplantation is an effective treatment for end-stage liver disease, but a huge gap remains between the number of people who need a liver transplant and the number of organs available. In order to ...BACKGROUND: Liver transplantation is an effective treatment for end-stage liver disease, but a huge gap remains between the number of people who need a liver transplant and the number of organs available. In order to maximize donor organ access for adult and pediatric recipients, novel surgical and liver replacement procedures have evolved. Newer surgical techniques include split cadaveric liver transplantation and living donor liver transplantation (LDLT). With marginal and abnormal donor livers, despite tremendous advances in surgical technology, individual surgical procedure can not be completely brought into play unless effective measurements and basal studies are undertaken. DATA SOURCES: A literature search of MEDLINE and the Web of Science database using 'liver transplantation' and 'expanding donor pool' was conducted and research articles were reviewed. RESULTS: Therapies directed toward scavenging O(2-), inhibiting nicotinamide adenine dinucleotide phosphate oxidase, and/or immuno-neutralizing tumor necrosis factor-alpha may prove useful in limiting the liver injury induced by surgical procedures such as split liver transplantation or LDLT. Improved donor organ perfusion and preservation methods, modulation of inflammatory cytokines, energy status enhancement, microcirculation amelioration, and antioxidant usage can improve non-heart beating donor liver transplantation. Effective measures have been taken to improve the local conditions of donor cells with steatosis, including usage of fat-derived hormone and inflammatory mediators, ischemic preconditioning, depletion of Kupffer cells, and cytokine antibody and gene therapy. Double-filtration plasmapheresis can effectively reduce HCV viremia and prevent HCV recurrence in patient with high HCV RNA levels after LDLT. CONCLUSIONS: Shortage of grafts and poor function of marginal and abnormal donor grafts put many patients at risk of death in waiting for liver transplantation. Advances in surgical technology, combined with improvement and breakthroughs in basic studies hold a promise in expanding the liver donor pool.展开更多
A general expression of the dynamic surface adsorption [Г(t)] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Differen...A general expression of the dynamic surface adsorption [Г(t)] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Different from the result of the still spherical surface, two factors (smaller than 1) appeared in the equation for the short time adsorption. Using the derived results, the adsorption kinetics of aqueous decanoyl-N-methylglucamine (Mega-10) solution was studied. In the short time region (t→0), a good agreement of experimental results with the theory was reached and the adsorption was controlled by diffusion.展开更多
Magnetized laser-produced plasmas are central to many studies in laboratory astrophysics,in inertial confinement fusion,and in industrial applications.Here,we present the results of large-scale three-dimensional magne...Magnetized laser-produced plasmas are central to many studies in laboratory astrophysics,in inertial confinement fusion,and in industrial applications.Here,we present the results of large-scale three-dimensional magnetohydrodynamic simulations of the dynamics of a laser-produced plasma expanding into a transverse magnetic field with a strength of tens of teslas.The simulations show the plasma being confined by the strong magnetic field into a slender slab structured by the magnetized Rayleigh–Taylor instability that develops at the plasma–vacuum interface.We find that when the initial velocity of the plume is perturbed,the slab can develop kink-like motions that disrupt its propagation.展开更多
An effective approach to expand the bandwidth of negative permeability of small-sized planax materials is proposed. Based on qualitative analysis of equivalent circuit models, the fractional bandwidth of an μ-negati...An effective approach to expand the bandwidth of negative permeability of small-sized planax materials is proposed. Based on qualitative analysis of equivalent circuit models, the fractional bandwidth of an μ-negative (MNG) material is expanded from 3.53% up to 12.87% by adding split-ring resonators (SRRs) and arranging them by proposed steps. Moreover, the experimental results validate the effectiveness of bandwidth-expanding methods, which is promising for the extensive application of metamaterials in the microwave field.展开更多
An incompressible flow in a porous channel with expanding or contacting walls in the presence of a transverse magnetic field is considered. Using similarity transformations, the governing equations are reduced to the ...An incompressible flow in a porous channel with expanding or contacting walls in the presence of a transverse magnetic field is considered. Using similarity transformations, the governing equations are reduced to the nonlinear ordinary differential equations. The exact similar solutions for the different cases of the expansion ratio and the Hartmann number are obtained with a singular perturbation method, and the associated behavior is discussed in detail.展开更多
A direct method for obtaining the expanding integrable models of the hierarchies of evolution equations was proposed. By using the equivalent transformation between the matrices, a new isospectral problem was directly...A direct method for obtaining the expanding integrable models of the hierarchies of evolution equations was proposed. By using the equivalent transformation between the matrices, a new isospectral problem was directly established according to the known isospectral problem, which can be used to obtain the expanding integrable model of the known hierarchy.展开更多
The most striking contrasts that are found on the continents in paleogeographic reconstructions of the end of the Mesozoic era are the occurrence on the place of the disappeared humid subtropics of the largest Gobi De...The most striking contrasts that are found on the continents in paleogeographic reconstructions of the end of the Mesozoic era are the occurrence on the place of the disappeared humid subtropics of the largest Gobi Desert in Eurasia with air temperatures falling below 50°from the freezing point and annual precipitation totals at the level of 100 mm. Science does not know the processes that can lead to a cooling of the atmosphere at 70°and other equally radical changes in nature with a stable position of the blocks of the earth’s crust in space. Changes in the environment of this magnitude can only be the result of land moving northward for a distance equal to about half the radius of the Earth. Titanosaurs, described by the remains in the Gobi deposits, had a body volume, which at modern gravity corresponds to a mass of 10 to 30 ton. However, animals with such a mass and such growth could not exist now. To create the necessary pressure in the vessels and provide energy to the body, Mongolian sauropods would need a heart of 2 - 3 m in diameter. Known types of muscle tissue are unable to maintain an elongated neck and head with a mass of more than a ton. The femur bones of four-legged dinosaurs had strength sufficient to move on land only animals weighing no more than 5 - 7 tons. The bones of giant bipedal dinosaurs at a constant gravitational field would have to be subjected to specific loads, several times greater than the bones of modern elephants, which is excluded. The natural conclusion about the action of a lesser gravity in the Mesozoic provides a solution to the mystery of the truly global spread in that era of bipedal mode of movement as the most energy efficient.展开更多
In the promotion of the modern enterprise system, the Shanghai Hero Co. Ltd. learns to develop assets operation, trying every means to make active the existing stock, using less cash to control more capital and operat...In the promotion of the modern enterprise system, the Shanghai Hero Co. Ltd. learns to develop assets operation, trying every means to make active the existing stock, using less cash to control more capital and operate larger amount of assets, while attaching great importance to product operation.展开更多
文摘The CICG President Du Zhanyuan shares his insights about China-Europe talent cooperation.THE history of exchange between China and Europe is long and profound.Since the 16th century,European thinkers represented by Voltaire,Bertrand Russell,and Arnold Joseph Toynbee have taken Chinese philosophy as a valuable complement to the European ideological system.China has also absorbed the ideas of European giants such as Adam Smith,Georg Wilhelm Friedrich Hegel,and Karl Marx for its transformation and progress.In recent years,exchanges and interactions between the two sides in various fields have become increasingly close.
文摘BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on safety and duration for metal stents in this setting is scarce.Due to limited access to endoscopic retrograde cholan-giopancreatography(ERCP)during the coronavirus disease 2019 pandemic in our centre,there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy.This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.METHODS Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query.Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records.The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months.Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for≤120 d or>120 d.RESULTS During the study period,a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course.In 33 ERCPs,the stent was removed or exchanged on a 3-month interval.No pancreatitis,perfor-ations or deaths occurred.Minor post-ERCP complications were similar between the 3-month(abdominal pain and intraductal migration)and 6-month(abdominal pain,septic shower and embedded stent)groups-6.1%vs 9.1%respectively,P=0.40.All strictures resolved at the end of the stenting course,but the stenting course was variable from 3 to 22 months.The recurrence rate for stenting courses lasting for up to 120 d was 71.4%and 21.4%for stenting courses of 121 d or over(P=0.03).There were 28 patients that were treated with a single ERCP with Kaffes,21 with removal after 120 d and 7 within 120 d.There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course(71.0%vs 10.0%,P=0.01).CONCLUSION Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.
文摘The hidden world of amyloid biology has suddenly snapped into atomic-level focus,revealing over 80 amyloid protein fibrils,both pathogenic and functional.Unlike globular proteins,amyloid proteins flatten and stack into unbranched fibrils.Stranger still,a single protein sequence can adopt wildly different two-dimensional conformations,yielding distinct fibril polymorphs.
文摘As 2024 comes to an end,the pickup in consumption and robust growth in a range of sectors have bolstered confidence that the Chinese economy is right on track to meet the preset growth rate of around five percent.Benefiting from a flurry of consumption-stimulating policies and measures,China’s online retail sales surpassed RMB 14 trillion in the January-November period,a year-on-year increase of 7.4 percent.Imports and exports maintained steady growth,climbing by 4.9 percent year-on-year in renminbi terms.Value-added industrial output also expanded 5.8 percent year-on-year.The volume of express delivery parcels reached a new high of 150 billion and is expected to grow higher still given the new-year festivities ahead.
文摘The two major challenges in industrial enzymatic catalysis are the limited number of chemical reaction types that are catalyzed by enzymes and the instability of enzymes under harsh conditions in industrial catalysis.Expanding enzyme catalysis to a larger substrate scope and greater variety of chemical reactions and tuning the microenvironment surrounding enzyme molecules to achieve high enzyme performance are urgently needed.In this account,we focus on our efforts using the de novo approach to synthesis hybrid enzyme catalysts that can address these two challenges and the structure-function relationship is discussed to reveal the principles of designing hybrid enzyme catalysts.We hope that this account will promote further efforts toward fundamental research and wide applications of designed enzyme hybrid catalysts for expanding biocatalysis.
文摘Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During range expansion, native species also encounter many new plant competitors. Thus, allelochemicals from native expanding species may also be more novel and allelopathic than those from non-expanding species to other plant competitors in the expanded range. We test this hypothesis using the native expanding Merremia boisiana and its non-expanding congener M. vitifolia in year 2012 inthe expanded range inHainan. In petridish bioassays, we found that aqueous extracts of M. boisiana leaves were often less inhibitory or more stimulatory to seed germination and seedling growth of five vegetable species than those of M. vitifolia leaves. In pot culture, we also found that aqueous leaf extracts of the two congeners could both inhibit the growth of a naturally co-occurring plant Paederia scanden, but their effects did not differ from each other. These results indicate that while allelopathy may contribute to the competitive ability of M. boisiana, it may not act as a novel weapon explaining its success in the expanded range in Hainan.
文摘On the basis of defining the concept of "immiserizing growth in expanding economies",through analysing the status quo of economy in China's rural areas in the new era,this paper aims to find out the factors responsible for economic weakness of China's rural residents.It analyses the impact of market consuming economy on growth economy,and points out the phenomenon of "immiserizing growth in expanding economies" which may be triggered by China's rapid rural economic growth as follows:first,the income disparity between urban and rural residents increases ceaselessly,the commodity prices continuously soar,and the rural residents' market consuming capacity is short;second,the wealth concentrates highly and the majority of farmers' income is low.Thus we put forward the countermeasures and proposals for preventing "immiserizing growth in expanding economies" in rural areas as follows:we should reform household registration system so that the rural residents have the right to migrate freely,and farmers' status is promoted;we should coordinate urban-rural development,strengthen agriculture and rural infrastructure building and achieve impartial allocation of public resources;we should carry out redistribution on income scientifically and effectively,consolidate rural social security system,bridge urban-rural income gap,transform the comparative advantage into competitive advantage,so as to circumvent "immiserizing growth in expanding economies".
基金supported by the National Natural Science Foundations of China (50936003, 50905013)The Open Project of State Key Lab. for Adv. Matals and Materials (2009Z-02)Research Foundation of Engineering Research Institute of USTB
文摘In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homotopy analysis method (HAM) is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail.
文摘A one-dimensional theoretical model was adopted in this paper to describe and analyze the flow in an expanding RBCC(rocket based combined cycle)duct.It can be concluded that the expanding angle,heating amount and distribution of heating play crucial roles on the thermal choking.They mainly influence the acceleration of flow,the position of choking throat and the total pressure loss.In order to fulfill the transition of subsonic flow to supersonic flow in the expanding RBCC duct,the heating amount has to change from a bigger value to a smaller one along the duct.When the thermal choking occurs in the RBCC duct,the moderate expanding angle,proper heating amount and distribution of heating are necessary for the best performance of RBCC combustor.Adopting the RBCC duct with smaller expanding angles anterior and bigger expanding angles posterior has positive effects on the thermal choking and flexibility of selecting heating method,and can restrain the negative effect of the combustion on the inlet also.
文摘The introduction of laparoscopic procedures is one of the milestones of surgical innovation over the past few decades. The advantages of minimally invasive approach have been gradually accepted owing to its less postoperative pain, reduced morbidity and faster recovery. Also, since the introduction of laparoscopic approach of liver surgery in 1955 (1), the benefit of the procedure had long been questioned but expected.
基金Project supported by the National Natural Science Foundation of China(Nos.50936003 and 50905013)the Open Project of State Key Laboratory for Advanced Metals and Materials (No.2009Z-02)
文摘The flow of a micropolar fluid in a semi-porous channel with an expanding or contracting wall is investigated. The governing equations are reduced to ordinary ones by using similar transformations. To get the analytic solution to the problem, the homotopy analysis method (HAM) is employed to obtain the expressions for velocity fields. Graphs are sketched and discussed for various parameters, especially the effect of the expansion ratio on velocity and micro-rotation fields.
基金supported by a grant from the Science and Technology Commission of Zhejiang Province, China (2006C13020)
文摘BACKGROUND: Liver transplantation is an effective treatment for end-stage liver disease, but a huge gap remains between the number of people who need a liver transplant and the number of organs available. In order to maximize donor organ access for adult and pediatric recipients, novel surgical and liver replacement procedures have evolved. Newer surgical techniques include split cadaveric liver transplantation and living donor liver transplantation (LDLT). With marginal and abnormal donor livers, despite tremendous advances in surgical technology, individual surgical procedure can not be completely brought into play unless effective measurements and basal studies are undertaken. DATA SOURCES: A literature search of MEDLINE and the Web of Science database using 'liver transplantation' and 'expanding donor pool' was conducted and research articles were reviewed. RESULTS: Therapies directed toward scavenging O(2-), inhibiting nicotinamide adenine dinucleotide phosphate oxidase, and/or immuno-neutralizing tumor necrosis factor-alpha may prove useful in limiting the liver injury induced by surgical procedures such as split liver transplantation or LDLT. Improved donor organ perfusion and preservation methods, modulation of inflammatory cytokines, energy status enhancement, microcirculation amelioration, and antioxidant usage can improve non-heart beating donor liver transplantation. Effective measures have been taken to improve the local conditions of donor cells with steatosis, including usage of fat-derived hormone and inflammatory mediators, ischemic preconditioning, depletion of Kupffer cells, and cytokine antibody and gene therapy. Double-filtration plasmapheresis can effectively reduce HCV viremia and prevent HCV recurrence in patient with high HCV RNA levels after LDLT. CONCLUSIONS: Shortage of grafts and poor function of marginal and abnormal donor grafts put many patients at risk of death in waiting for liver transplantation. Advances in surgical technology, combined with improvement and breakthroughs in basic studies hold a promise in expanding the liver donor pool.
基金Supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars (D4200111).
文摘A general expression of the dynamic surface adsorption [Г(t)] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Different from the result of the still spherical surface, two factors (smaller than 1) appeared in the equation for the short time adsorption. Using the derived results, the adsorption kinetics of aqueous decanoyl-N-methylglucamine (Mega-10) solution was studied. In the short time region (t→0), a good agreement of experimental results with the theory was reached and the adsorption was controlled by diffusion.
基金This work was supported by funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant Agreement No.787539)The research leading to these results is supported by Extreme Light Infrastructure Nuclear Physics(ELI-NP)Phase II a project co-financed by the Romanian Government and European Union through the European Regional Development Fund+1 种基金the Project No.ELI-RO-2020-23 funded by IFA(Romania)This work was also granted access to the HPC resources of MesoPSL financed by the Region Ile de France and the project Equip at Meso(Reference No.ANR-10-EQPX-29-01)of the program Investissements d’Avenir supervised by the National Agency for Research.
文摘Magnetized laser-produced plasmas are central to many studies in laboratory astrophysics,in inertial confinement fusion,and in industrial applications.Here,we present the results of large-scale three-dimensional magnetohydrodynamic simulations of the dynamics of a laser-produced plasma expanding into a transverse magnetic field with a strength of tens of teslas.The simulations show the plasma being confined by the strong magnetic field into a slender slab structured by the magnetized Rayleigh–Taylor instability that develops at the plasma–vacuum interface.We find that when the initial velocity of the plume is perturbed,the slab can develop kink-like motions that disrupt its propagation.
基金Project supported partially by the National Natural Science Foundation of China (Grant Nos. 60872034 and 60971029)the New-Century Talent Program of the Education Department of China (Grant No. NCET070154)+1 种基金the National Defense Research Funding (Grant No. ZJ10DZ02111)the Hi-Tech Research and Development Program of China (Grant No. 2009AA01Z231)
文摘An effective approach to expand the bandwidth of negative permeability of small-sized planax materials is proposed. Based on qualitative analysis of equivalent circuit models, the fractional bandwidth of an μ-negative (MNG) material is expanded from 3.53% up to 12.87% by adding split-ring resonators (SRRs) and arranging them by proposed steps. Moreover, the experimental results validate the effectiveness of bandwidth-expanding methods, which is promising for the extensive application of metamaterials in the microwave field.
文摘An incompressible flow in a porous channel with expanding or contacting walls in the presence of a transverse magnetic field is considered. Using similarity transformations, the governing equations are reduced to the nonlinear ordinary differential equations. The exact similar solutions for the different cases of the expansion ratio and the Hartmann number are obtained with a singular perturbation method, and the associated behavior is discussed in detail.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10371070, 10547123)
文摘A direct method for obtaining the expanding integrable models of the hierarchies of evolution equations was proposed. By using the equivalent transformation between the matrices, a new isospectral problem was directly established according to the known isospectral problem, which can be used to obtain the expanding integrable model of the known hierarchy.
文摘The most striking contrasts that are found on the continents in paleogeographic reconstructions of the end of the Mesozoic era are the occurrence on the place of the disappeared humid subtropics of the largest Gobi Desert in Eurasia with air temperatures falling below 50°from the freezing point and annual precipitation totals at the level of 100 mm. Science does not know the processes that can lead to a cooling of the atmosphere at 70°and other equally radical changes in nature with a stable position of the blocks of the earth’s crust in space. Changes in the environment of this magnitude can only be the result of land moving northward for a distance equal to about half the radius of the Earth. Titanosaurs, described by the remains in the Gobi deposits, had a body volume, which at modern gravity corresponds to a mass of 10 to 30 ton. However, animals with such a mass and such growth could not exist now. To create the necessary pressure in the vessels and provide energy to the body, Mongolian sauropods would need a heart of 2 - 3 m in diameter. Known types of muscle tissue are unable to maintain an elongated neck and head with a mass of more than a ton. The femur bones of four-legged dinosaurs had strength sufficient to move on land only animals weighing no more than 5 - 7 tons. The bones of giant bipedal dinosaurs at a constant gravitational field would have to be subjected to specific loads, several times greater than the bones of modern elephants, which is excluded. The natural conclusion about the action of a lesser gravity in the Mesozoic provides a solution to the mystery of the truly global spread in that era of bipedal mode of movement as the most energy efficient.
文摘In the promotion of the modern enterprise system, the Shanghai Hero Co. Ltd. learns to develop assets operation, trying every means to make active the existing stock, using less cash to control more capital and operate larger amount of assets, while attaching great importance to product operation.