This work investigates the effects of the excluded volume and especially those of the chain stiffness on the structural and dynamical properties of a model polymer chain. The theoretical framework is the same as in th...This work investigates the effects of the excluded volume and especially those of the chain stiffness on the structural and dynamical properties of a model polymer chain. The theoretical framework is the same as in the recent works by Steinhauser et al., where a Rouse approach is adopted. Our model differs in that our chains have a finite average bending angle. As in the works by Steinhauser et al., Langevin dynamic simulations were performed without hydrodynamic interactions. Whereas this doesn＇t impact the static properties we obtain, it also allows us to compare our results on dynamic properties to those predicted by Rouse theory, where hydrodynamic interactions are also neglected. Our results show that the structural properties are very sensitive to the chain stiffness, whereas the dynamic scaling laws remain the same as those by Rouse theory, with the prefactor depending on the persistence length.展开更多
Understanding the excluded volume of anisotropic particle is of great importance in the evaluation of continuum percolation and random packing behaviors of soft/hard particle systems in heterogeneous disordered media....Understanding the excluded volume of anisotropic particle is of great importance in the evaluation of continuum percolation and random packing behaviors of soft/hard particle systems in heterogeneous disordered media.In this work,we obtain the excluded volumes of several anisotropic convex particles including prolate spheroids,oblate spheroids,spherocylinders,and Platonic particles,using theoretical and numerical approaches.According to the second virial coefficient,we first present a theoretical scheme for determining the excluded volumes of anisotropic particles.Also,the mean tangent diameters of anisotropic convex particles are formulated by the quantitative stereology.Subsequently,Monte Carlo simulations are demonstrated to numerically evaluate the excluded volumes.The theoretical results of the dimensionless excluded volume are thereafter compared with that of the numerical results to verify the validity of the theoretical scheme.We further investigate the dependence of the dimensionless excluded volume on the geometric characteristics of anisotropic particles based on the proposed theoretical and numerical schemes.Results show that the dimensionless excluded volume mainly relies on the shape and surface information of anisotropic particles.The developed theoretical and numerical schemes can provide theoretical insights into the percolation threshold and packing density of soft/hard anisotropic particle systems in heterogeneous materials,physics,and chemistry fields.展开更多
A theoretical model for the translocation process of biomacromolecule is developed based on the self-consistent field theory （SCFT）, where the biomacromolecule is regarded as a self-avoiding polymer chain actuated b...A theoretical model for the translocation process of biomacromolecule is developed based on the self-consistent field theory （SCFT）, where the biomacromolecule is regarded as a self-avoiding polymer chain actuated by the external potential. In this theoretical model, the external potential, the Coulomb electrostatic potential of the charged ions （the electrolyte effect）, and the attractive interaction between the polymer and the nanopore （the excluded volume effect） are all considered, which have effects on the free energy landscape and conformation entropy during the translocation stage. The result shows that the entropy barrier of the polymer in the solution with high valence electrolyte is much larger than that with low valence electrolyte under the same condition, leading to that the translocation time of the DNA molecules in the solution increases when the valence electrolyte increases. In addition, the attractive interaction between the polymer and the nanopore increases the free energy of the polymer, which means that the probability of the translocation through the nanopore increases. The average translocation time decreases when the excluded volume effect parameter increases. The electrolyte effect can prolong the average translocation time. The simulation results agree well with the available experimental results.展开更多
One of the mainly interesting things of matroid theory is the representability of a matroid. Finding the set of all excluded minors for the representability is the solution of the representability. In 2000, Geelen, Ge...One of the mainly interesting things of matroid theory is the representability of a matroid. Finding the set of all excluded minors for the representability is the solution of the representability. In 2000, Geelen, Gerards and Kapoor proved that is the complete set of GF(4)-representability. In this paper, we show that is an excluded minor for GF(4)-representability.展开更多
In order to prevent public hearings from becoming a farce,the city of Guangzhou,capital of south China’s Guangdong Province,enacted trial regulations to ensure more fairness and justice at public hearings,which are o...In order to prevent public hearings from becoming a farce,the city of Guangzhou,capital of south China’s Guangdong Province,enacted trial regulations to ensure more fairness and justice at public hearings,which are organized when local residents have major disagreements on important city issues.展开更多
The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical s...The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical symptoms but also delayed the developmental pro-cess of this disorder. It also verified the correctness of the traditional theory that the kidney dominates the bone and generates the marrow.展开更多
Uroschesis is manifested by. incompleteness or difficulty in urination or even incapability of urination. Clinically, the symptoms include retention of urine and anuria induced by a variety of causes. In this study, t...Uroschesis is manifested by. incompleteness or difficulty in urination or even incapability of urination. Clinically, the symptoms include retention of urine and anuria induced by a variety of causes. In this study, the patients with anuria or oliguria due to lesions of renal parenchyma or renal failure were excluded. Using acupuncture, the author had treated 36 cases of functional uroshesis with satisfactory results as reported in the following.展开更多
We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retros...We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retrospective analysis of potential living donors(n = 1004) between May 2004 and December 2012. This report focuses on the analysis of causes, duration, cost, and various implications of donor exclusion(n = 792).Most of the transplant candidates(82.3%) had an experience with more than one excluded donor(median = 3). Some recipients travelled abroad for a deceased donor transplant(n = 12) and some died before finding a suitable donor(n = 14). The evaluation of an excluded donor is a time-consuming process(median = 3 d, range 1 d to 47 d). It is also a costly process with a median cost of approximately 70 USD(range 35 USD to 885 USD). From these results, living donor exclusion has negative implications on the patients and transplant program with ethical dilemmas and an economic impact. Many strategies are adopted by other centers to expand the donor pool; however, they are not all applicable in our locality. We conclude that an active legalized deceased donor transplantation program is necessary to overcome the shortage of available liver grafts in Egypt.展开更多
Chain architecture effect on static and dynamic properties of unentangled polymers is explored by molecular dynamics simulation and Rouse mode analysis based on graph theory.For open chains,although they generally obe...Chain architecture effect on static and dynamic properties of unentangled polymers is explored by molecular dynamics simulation and Rouse mode analysis based on graph theory.For open chains,although they generally obey ideal scaling in chain dimensions,local structure exhibits nonideal behavior due to the incomplete excluded volume(EV)screening,the reduced mean square internal distance(MSID)can be well described by Wittmer'theory for linear chains and the resulting chain swelling is architecture dependent,i.e.,the more branches a bit stronger swelling.For rings,unlike open chains they are compact in term of global sizes.Due to EV effect and nonconcatenated constraints their local structure exhibits a quite different non-Gaussian behavior from open chains,i.e.,reduced MSID curves do not collapse to a single master curve and fail to converge to a chain-length-independent constant,which makes the direct application of Wittmer's theory to rings quite questionable.Deviation from ideality is further evidenced by limited applicability of Rouse prediction to mode amplitude and relaxation time at high modes as well as the non-constant and mode-dependent scaled Rouse mode amplitudes,while the latter is architecture-dependent and even molecular weight dependent for rings.The chain relaxation time is architecture-dependent,but the same scaling dependence on chain dimensions does hold for all studied architectures.Despite mode orthogonality at static state,the role of cross-correlation in orientation relaxation increases with time and the time-dependent coupling parameter rises faster for rings than open chains even at short time scales it is lower for rings.展开更多
Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the classification problem of all 256 elementary cellular automata is discussed from the point of view of time series generated ...Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the classification problem of all 256 elementary cellular automata is discussed from the point of view of time series generated by them,and examples in each class are provided to explain the methods used.展开更多
The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being bot...The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and vip polymer in solution.The intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent interactions.It was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in solution.The viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_c.The effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.展开更多
In order to increase the expression of mdrl genetransfectcd using retroviral vcctors, we constructedtwo retroviral vectors (LmdrlSN and MSCV-mdrl)containing mdrl cDNA and compared the expressionof mdrl gene with anoth...In order to increase the expression of mdrl genetransfectcd using retroviral vcctors, we constructedtwo retroviral vectors (LmdrlSN and MSCV-mdrl)containing mdrl cDNA and compared the expressionof mdrl gene with another vector pHamdrl/A(Pastan et al. Proc Natl Acad Sci USA 85: 4486,1986) in NIH.3T3 cells. The LmdrlSN was made展开更多
Membrane tubes are important functional elements for riving cells. Experiments have found that membrane tubes can be extracted from giant lipid vesicles by groups of kinesin. How these motors cooperate in extracting t...Membrane tubes are important functional elements for riving cells. Experiments have found that membrane tubes can be extracted from giant lipid vesicles by groups of kinesin. How these motors cooperate in extracting the membrane tube is a very important issue but still unclear so far. In this paper, we propose a cooperation mechanism called two-track-dumbbell model, in which kinesin is regarded as a dumbbell with an end （tail domain） tethered on the fluid-like membrane and the other end （head domain） stepping on the microtubule. Taking account of the elasticity of kinesin molecule and the excluded volume effect of both the head domain and the tail domain of kinesin, which are not considered in previous models, we simulate the growth process of the membrane tube pulled by kinesin motors. Our results indicate that in the case of strong or moderate exclusion of motor tails, the average number of motors pulling the tube can be as high as 9 and thus motors moving along a single microtubule protofilament can generate enough force to extract membrane tubes from vesicles. This result is different from previous studies and may be tested by future experiments.展开更多
Hydride generation (HG)technique has been widely used for the determination of volatile hydride forming elements by atomic spectroscopy since Holak reported the determination of arsenic with this technique using atomi...Hydride generation (HG)technique has been widely used for the determination of volatile hydride forming elements by atomic spectroscopy since Holak reported the determination of arsenic with this technique using atomic absorption spectrometry in 1969. The most commonly used展开更多
Introduction: A transcatheter closure of atrial septal defect(ASD)with the Amplatzer septal occluder(ASO)is a newperspective non-surgical method of treatment of this congenitalheart defect.The aim of the study was to ...Introduction: A transcatheter closure of atrial septal defect(ASD)with the Amplatzer septal occluder(ASO)is a newperspective non-surgical method of treatment of this congenitalheart defect.The aim of the study was to determine the rate of suitable defectsfur this new non-surgical techuique.Patients and methods:From9/95-9/97,77 patients with secundum ASD underwent an attemptat transcatheter closure;.at a median age of 9.3 yr.(range,2.1-43.5 yr.)and meaian weight of 32 kg(range,13-68kg).The most important echocardiograghic criteria for successfulctosure are sufficient rims around the defect,diameter ot medefect and total length of atrial septum.3 pts which not fulfilcriteria were excluded from transthoracic echocardiograpny(TTE).11 pts were excluded from transesophageal TTE,2 ptswere excluded during intervention.we evaluate this results anacompare it with the values frrom perioperative morphomethry otASD’s in 353 patients who underwent surgety(years-90).Results:The medlian ASD size measured by TEE was 11.7 mm(range,5-23 mm)and the median stretched diameter was 13.9mm(range,5-24 mm).All devices were placed correctly.Therewas no complication related to the closure.On a median follow-up interval of 8.5 months(range 0.4-2.2 yr)there has been noepisodes of endocarditis,thromboembofism or wire fracture and58/61 pts(95%)had complete closure,as assessed by TTE.Conclusion From 77 patiehts 61 fulfil criteria and successfullyunderwent a transcathter closure of ASD,which represents 79%.In 353 patients who underwent surgery authors compare the areaof the defect and the septal area.278 pts(78%)had suitabledefect for transcatheter closure.We conclude that a new selfexpandable,repositionable ASO is affording a safe and defectivemethod to close small-large secundum ASD’s.Suitable defectsfor this procedure are in the majority(up to 80%)of patients withsecundum ASD.展开更多
基金financially supported by the National Natural Science Foundation of China(No.10572056)
文摘This work investigates the effects of the excluded volume and especially those of the chain stiffness on the structural and dynamical properties of a model polymer chain. The theoretical framework is the same as in the recent works by Steinhauser et al., where a Rouse approach is adopted. Our model differs in that our chains have a finite average bending angle. As in the works by Steinhauser et al., Langevin dynamic simulations were performed without hydrodynamic interactions. Whereas this doesn＇t impact the static properties we obtain, it also allows us to compare our results on dynamic properties to those predicted by Rouse theory, where hydrodynamic interactions are also neglected. Our results show that the structural properties are very sensitive to the chain stiffness, whereas the dynamic scaling laws remain the same as those by Rouse theory, with the prefactor depending on the persistence length.
基金The authors acknowledge financial supports from National Natural Science Foundation Project of China(Grant No.11402076)Natural Science Foundation Project for Jiangsu Province(Grant No.BK20130841)+5 种基金China Postdoctoral Science Foundation Funded Project(Grant Nos.2014M560385 and 2015T80493)the Open Research Fund of State Key Laboratory of Structural Analysis for Industrial Equipment(Grant No.GZ1405)the Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin(Grant No.IWHR-SKL-201511)the Open Research Fund of Jiangsu Key Laboratory of Construction Materials(Grant No.CM2014-03)Jiangsu Postdoctoral Science Foundation Project(Grant No.1402053C)Research Special of the China Institute of Water Resources and Hydropower Research(Grant No.KY1640).
文摘Understanding the excluded volume of anisotropic particle is of great importance in the evaluation of continuum percolation and random packing behaviors of soft/hard particle systems in heterogeneous disordered media.In this work,we obtain the excluded volumes of several anisotropic convex particles including prolate spheroids,oblate spheroids,spherocylinders,and Platonic particles,using theoretical and numerical approaches.According to the second virial coefficient,we first present a theoretical scheme for determining the excluded volumes of anisotropic particles.Also,the mean tangent diameters of anisotropic convex particles are formulated by the quantitative stereology.Subsequently,Monte Carlo simulations are demonstrated to numerically evaluate the excluded volumes.The theoretical results of the dimensionless excluded volume are thereafter compared with that of the numerical results to verify the validity of the theoretical scheme.We further investigate the dependence of the dimensionless excluded volume on the geometric characteristics of anisotropic particles based on the proposed theoretical and numerical schemes.Results show that the dimensionless excluded volume mainly relies on the shape and surface information of anisotropic particles.The developed theoretical and numerical schemes can provide theoretical insights into the percolation threshold and packing density of soft/hard anisotropic particle systems in heterogeneous materials,physics,and chemistry fields.
基金supported by the National Natural Science Foundation of China(No.51375090)
文摘A theoretical model for the translocation process of biomacromolecule is developed based on the self-consistent field theory （SCFT）, where the biomacromolecule is regarded as a self-avoiding polymer chain actuated by the external potential. In this theoretical model, the external potential, the Coulomb electrostatic potential of the charged ions （the electrolyte effect）, and the attractive interaction between the polymer and the nanopore （the excluded volume effect） are all considered, which have effects on the free energy landscape and conformation entropy during the translocation stage. The result shows that the entropy barrier of the polymer in the solution with high valence electrolyte is much larger than that with low valence electrolyte under the same condition, leading to that the translocation time of the DNA molecules in the solution increases when the valence electrolyte increases. In addition, the attractive interaction between the polymer and the nanopore increases the free energy of the polymer, which means that the probability of the translocation through the nanopore increases. The average translocation time decreases when the excluded volume effect parameter increases. The electrolyte effect can prolong the average translocation time. The simulation results agree well with the available experimental results.
文摘One of the mainly interesting things of matroid theory is the representability of a matroid. Finding the set of all excluded minors for the representability is the solution of the representability. In 2000, Geelen, Gerards and Kapoor proved that is the complete set of GF(4)-representability. In this paper, we show that is an excluded minor for GF(4)-representability.
文摘In order to prevent public hearings from becoming a farce,the city of Guangzhou,capital of south China’s Guangdong Province,enacted trial regulations to ensure more fairness and justice at public hearings,which are organized when local residents have major disagreements on important city issues.
文摘The method of scoring kidney deficiency symptoms and bone density was used to judge therapeutic efficacy on osteoporosis of traditional kidney-tonifying drugs. It was proved that the drugs not only improved clinical symptoms but also delayed the developmental pro-cess of this disorder. It also verified the correctness of the traditional theory that the kidney dominates the bone and generates the marrow.
文摘Uroschesis is manifested by. incompleteness or difficulty in urination or even incapability of urination. Clinically, the symptoms include retention of urine and anuria induced by a variety of causes. In this study, the patients with anuria or oliguria due to lesions of renal parenchyma or renal failure were excluded. Using acupuncture, the author had treated 36 cases of functional uroshesis with satisfactory results as reported in the following.
文摘We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retrospective analysis of potential living donors(n = 1004) between May 2004 and December 2012. This report focuses on the analysis of causes, duration, cost, and various implications of donor exclusion(n = 792).Most of the transplant candidates(82.3%) had an experience with more than one excluded donor(median = 3). Some recipients travelled abroad for a deceased donor transplant(n = 12) and some died before finding a suitable donor(n = 14). The evaluation of an excluded donor is a time-consuming process(median = 3 d, range 1 d to 47 d). It is also a costly process with a median cost of approximately 70 USD(range 35 USD to 885 USD). From these results, living donor exclusion has negative implications on the patients and transplant program with ethical dilemmas and an economic impact. Many strategies are adopted by other centers to expand the donor pool; however, they are not all applicable in our locality. We conclude that an active legalized deceased donor transplantation program is necessary to overcome the shortage of available liver grafts in Egypt.
基金supported by the National Natural Science Foundation of China(Nos.21790343,21574142,21174154)the National Key Research and Development Program of China(No.2016YFB1100800).
文摘Chain architecture effect on static and dynamic properties of unentangled polymers is explored by molecular dynamics simulation and Rouse mode analysis based on graph theory.For open chains,although they generally obey ideal scaling in chain dimensions,local structure exhibits nonideal behavior due to the incomplete excluded volume(EV)screening,the reduced mean square internal distance(MSID)can be well described by Wittmer'theory for linear chains and the resulting chain swelling is architecture dependent,i.e.,the more branches a bit stronger swelling.For rings,unlike open chains they are compact in term of global sizes.Due to EV effect and nonconcatenated constraints their local structure exhibits a quite different non-Gaussian behavior from open chains,i.e.,reduced MSID curves do not collapse to a single master curve and fail to converge to a chain-length-independent constant,which makes the direct application of Wittmer's theory to rings quite questionable.Deviation from ideality is further evidenced by limited applicability of Rouse prediction to mode amplitude and relaxation time at high modes as well as the non-constant and mode-dependent scaled Rouse mode amplitudes,while the latter is architecture-dependent and even molecular weight dependent for rings.The chain relaxation time is architecture-dependent,but the same scaling dependence on chain dimensions does hold for all studied architectures.Despite mode orthogonality at static state,the role of cross-correlation in orientation relaxation increases with time and the time-dependent coupling parameter rises faster for rings than open chains even at short time scales it is lower for rings.
文摘Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the classification problem of all 256 elementary cellular automata is discussed from the point of view of time series generated by them,and examples in each class are provided to explain the methods used.
文摘The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and vip polymer in solution.The intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent interactions.It was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in solution.The viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_c.The effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.
文摘In order to increase the expression of mdrl genetransfectcd using retroviral vcctors, we constructedtwo retroviral vectors (LmdrlSN and MSCV-mdrl)containing mdrl cDNA and compared the expressionof mdrl gene with another vector pHamdrl/A(Pastan et al. Proc Natl Acad Sci USA 85: 4486,1986) in NIH.3T3 cells. The LmdrlSN was made
基金Supported by the National Basic Research Program of China(973 Program)under Grant No.2013CB932800National Natural Science Foundation of China under Grant Nos.11205123,11075015,and 11105218
文摘Membrane tubes are important functional elements for riving cells. Experiments have found that membrane tubes can be extracted from giant lipid vesicles by groups of kinesin. How these motors cooperate in extracting the membrane tube is a very important issue but still unclear so far. In this paper, we propose a cooperation mechanism called two-track-dumbbell model, in which kinesin is regarded as a dumbbell with an end （tail domain） tethered on the fluid-like membrane and the other end （head domain） stepping on the microtubule. Taking account of the elasticity of kinesin molecule and the excluded volume effect of both the head domain and the tail domain of kinesin, which are not considered in previous models, we simulate the growth process of the membrane tube pulled by kinesin motors. Our results indicate that in the case of strong or moderate exclusion of motor tails, the average number of motors pulling the tube can be as high as 9 and thus motors moving along a single microtubule protofilament can generate enough force to extract membrane tubes from vesicles. This result is different from previous studies and may be tested by future experiments.
文摘Hydride generation (HG)technique has been widely used for the determination of volatile hydride forming elements by atomic spectroscopy since Holak reported the determination of arsenic with this technique using atomic absorption spectrometry in 1969. The most commonly used
文摘Introduction: A transcatheter closure of atrial septal defect(ASD)with the Amplatzer septal occluder(ASO)is a newperspective non-surgical method of treatment of this congenitalheart defect.The aim of the study was to determine the rate of suitable defectsfur this new non-surgical techuique.Patients and methods:From9/95-9/97,77 patients with secundum ASD underwent an attemptat transcatheter closure;.at a median age of 9.3 yr.(range,2.1-43.5 yr.)and meaian weight of 32 kg(range,13-68kg).The most important echocardiograghic criteria for successfulctosure are sufficient rims around the defect,diameter ot medefect and total length of atrial septum.3 pts which not fulfilcriteria were excluded from transthoracic echocardiograpny(TTE).11 pts were excluded from transesophageal TTE,2 ptswere excluded during intervention.we evaluate this results anacompare it with the values frrom perioperative morphomethry otASD’s in 353 patients who underwent surgety(years-90).Results:The medlian ASD size measured by TEE was 11.7 mm(range,5-23 mm)and the median stretched diameter was 13.9mm(range,5-24 mm).All devices were placed correctly.Therewas no complication related to the closure.On a median follow-up interval of 8.5 months(range 0.4-2.2 yr)there has been noepisodes of endocarditis,thromboembofism or wire fracture and58/61 pts(95%)had complete closure,as assessed by TTE.Conclusion From 77 patiehts 61 fulfil criteria and successfullyunderwent a transcathter closure of ASD,which represents 79%.In 353 patients who underwent surgery authors compare the areaof the defect and the septal area.278 pts(78%)had suitabledefect for transcatheter closure.We conclude that a new selfexpandable,repositionable ASO is affording a safe and defectivemethod to close small-large secundum ASD’s.Suitable defectsfor this procedure are in the majority(up to 80%)of patients withsecundum ASD.
