The bursty events of available bit rate (ABR) traffic challenge the research on flow control algorithm. This bursty nature makes the network difficult to guarantee some performance such as decreasing cell loss especia...The bursty events of available bit rate (ABR) traffic challenge the research on flow control algorithm. This bursty nature makes the network difficult to guarantee some performance such as decreasing cell loss especially when congestion appears. In addition the robust stability analysis in the presence of virtual connections (VCs) variation is another inherent problem of the current rate-based algorithm. An explicit rate-based scheme is concerned. Some mathematical methods are adopted to minimize overshoot in the buffer to eliminate the growing congestion quickly. Then in linear matrix inequality (LMI) forms via Lyapunov stability argument relating to robustness issues in the presence of time-varying VCs is purposed in linear matrix inequality. A set of numerical examples guarantees this choice of algorithm parameters is robust stability. The simulations further back up our results.展开更多
Von Willebrand Factor(VWF),a multimeric plasma glycoprotein,is synthesized in endothelial cells and megakaryocytes.In adhesion and aggregation of circulating platelets towards to the sites of vascular injury,VWF captu...Von Willebrand Factor(VWF),a multimeric plasma glycoprotein,is synthesized in endothelial cells and megakaryocytes.In adhesion and aggregation of circulating platelets towards to the sites of vascular injury,VWF captures and activates the circulating platelets through interaction with platelet GPlba.As a triplet complex of A1A2A3,the VWF-A domain is a closed conformation with a low affinity to GPlba,but mutations or pathological hemodynamic environment of high fluid shear stress can induce the closed A domain to become an extended one.However,the key events in the force-and/or mutation-induced activation of VWF-A under flows remains unclear.Therefore,with techniques of AFM and PPFC,we here examined transformation of conformation and function of VWF-A under various wall shear stresses,for understanding regulation of force on VWF-A activation.Interesting,AFM scanning imaging data showed that VWF-A molecules on substrate pretreated by perfusing distilled water at various wall shear stresses shortened first and then lengthened as increasing of the pre-loaded wall shear stress,and the threshold of the wall shear stress is about 100 dyn/cm2,demonstrating that increasing pre-loaded wall shear stress would make the treated-A1A2A3 conformation gradually transform from a loose spherical structure to a compact one first and then become an open or extended one.The adhesion frequency of GPlba-coated Polystyrene microspheres(3-μm radius)on the VWF-A-coated substrates decreased first and then increased with the preloaded wall shear stress,which has a same threshold mentioned above.These results suggested that,force-induced activation of VWF-A occurs just at high wall shear stresses(>100 dyn/cm2).The mechanical stability of the closed A1A2A3 conformation would be weakened by the gain of function(GOF)mutant R1 308 L of A1 and enhanced by the loss of function(LOF)mutant G1324S,as it should be.To further reveal the molecular mechanism of the force-induced enhancing or weakening of VWF-A activation,we performed AFM experiment to investigate interaction of A1(WT A1 and its two mutants,the GOF mutant R1 308 L and the LOF mutant G1324S)with A2 and A3,respectively.The adhesive frequency of A1 with A2was larger than that of A1 with A3,showing that A1 was in favor of A2 rather than A3.And,the lifetimes of A1-A2 and A1-A3bond were biphasic force-dependent,showing a'Catch-slip bond'transform in binding of A1 to A2 or A3.It suggested that under the low wall shear stresses,force could inhibit VWF activity through a catch bond mechanism,which enhanced the stability of the closed A1A2A3 conformation,but under high wall shear stresses,the force would enhance VWF activity through a slip bond mechanism,which promoted conformational transform of VWF-A from closed to extended one through reducing the stability of the closed A1A2A3 structure.Our results showed that the GOF mutant R1 308 L would down-regulate the binding affinity of A1 to A2,leading to a low barrier in opening of the closed VWF-A structure.In contrast,the LOF mutant G1324S would enhance the stability of the closed VWF-A conformation by up-regulating the binding affinity of A1 to A2,leading to inhibition of VWF activity.展开更多
The Newton-Like algorithm with price estimation error in optimization flow control in network is analyzed. The estimation error is treated as inexactness of the gradient and the inexact descent direction is analyzed. ...The Newton-Like algorithm with price estimation error in optimization flow control in network is analyzed. The estimation error is treated as inexactness of the gradient and the inexact descent direction is analyzed. Based on the optimization theory, a sufficient condition for convergence of this algorithm with bounded price estimation error is obtained. Furthermore, even when this sufficient condition doesn't hold, this algorithm can also converge, provided a modified step size, and an attraction region is obtained. Based on Lasalle's invariance principle applied to a suitable Lyapunov function, the dynamic system described by this algorithm is proved to be global stability if the error is zero. And the Newton-Like algorithm with bounded price estimation error is also globally stable if the error satisfies the sufficient condition for convergence. All trajectories ultimately converge to the equilibrium point.展开更多
In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generate...In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generated by the state phase or its gradient(electronic current). The classical Shannon(S[p]) and Fisher(I[p]) information terms probe the entropic content of incoherent local events of the particle localization, embodied in the probability distribution p, while their nonclassical phase-companions, S[ Φ ] and I[ Φ ], provide relevant coherence information supplements.Thermodynamic-like couplings between the entropic and energetic descriptors of molecular states are shown to be precluded by the principles of quantum mechanics. The maximum of resultant entropy determines the phase-equilibrium state, defined by "thermodynamic" phase related to electronic density,which can be used to describe reactants in hypothetical stages of a bimolecular chemical reaction.Information channels of molecular systems and their entropic bond indices are summarized, the complete-bridge propagations are examined, and sequential cascades involving the complete sets of the atomic-orbital intermediates are interpreted as Markov chains. The QIT description is applied to reactive systems R = A―B, composed of the Acidic(A) and Basic(B) reactants. The electronegativity equalization processes are investigated and implications of the concerted patterns of electronic flows in equilibrium states of the complementarily arranged substrates are investigated. Quantum communications between reactants are explored and the QIT descriptors of the A―B bond multiplicity/composition are extracted.展开更多
文摘The bursty events of available bit rate (ABR) traffic challenge the research on flow control algorithm. This bursty nature makes the network difficult to guarantee some performance such as decreasing cell loss especially when congestion appears. In addition the robust stability analysis in the presence of virtual connections (VCs) variation is another inherent problem of the current rate-based algorithm. An explicit rate-based scheme is concerned. Some mathematical methods are adopted to minimize overshoot in the buffer to eliminate the growing congestion quickly. Then in linear matrix inequality (LMI) forms via Lyapunov stability argument relating to robustness issues in the presence of time-varying VCs is purposed in linear matrix inequality. A set of numerical examples guarantees this choice of algorithm parameters is robust stability. The simulations further back up our results.
基金supported by the National Natural Science Foundation of China ( 116272109,11432006)
文摘Von Willebrand Factor(VWF),a multimeric plasma glycoprotein,is synthesized in endothelial cells and megakaryocytes.In adhesion and aggregation of circulating platelets towards to the sites of vascular injury,VWF captures and activates the circulating platelets through interaction with platelet GPlba.As a triplet complex of A1A2A3,the VWF-A domain is a closed conformation with a low affinity to GPlba,but mutations or pathological hemodynamic environment of high fluid shear stress can induce the closed A domain to become an extended one.However,the key events in the force-and/or mutation-induced activation of VWF-A under flows remains unclear.Therefore,with techniques of AFM and PPFC,we here examined transformation of conformation and function of VWF-A under various wall shear stresses,for understanding regulation of force on VWF-A activation.Interesting,AFM scanning imaging data showed that VWF-A molecules on substrate pretreated by perfusing distilled water at various wall shear stresses shortened first and then lengthened as increasing of the pre-loaded wall shear stress,and the threshold of the wall shear stress is about 100 dyn/cm2,demonstrating that increasing pre-loaded wall shear stress would make the treated-A1A2A3 conformation gradually transform from a loose spherical structure to a compact one first and then become an open or extended one.The adhesion frequency of GPlba-coated Polystyrene microspheres(3-μm radius)on the VWF-A-coated substrates decreased first and then increased with the preloaded wall shear stress,which has a same threshold mentioned above.These results suggested that,force-induced activation of VWF-A occurs just at high wall shear stresses(>100 dyn/cm2).The mechanical stability of the closed A1A2A3 conformation would be weakened by the gain of function(GOF)mutant R1 308 L of A1 and enhanced by the loss of function(LOF)mutant G1324S,as it should be.To further reveal the molecular mechanism of the force-induced enhancing or weakening of VWF-A activation,we performed AFM experiment to investigate interaction of A1(WT A1 and its two mutants,the GOF mutant R1 308 L and the LOF mutant G1324S)with A2 and A3,respectively.The adhesive frequency of A1 with A2was larger than that of A1 with A3,showing that A1 was in favor of A2 rather than A3.And,the lifetimes of A1-A2 and A1-A3bond were biphasic force-dependent,showing a'Catch-slip bond'transform in binding of A1 to A2 or A3.It suggested that under the low wall shear stresses,force could inhibit VWF activity through a catch bond mechanism,which enhanced the stability of the closed A1A2A3 conformation,but under high wall shear stresses,the force would enhance VWF activity through a slip bond mechanism,which promoted conformational transform of VWF-A from closed to extended one through reducing the stability of the closed A1A2A3 structure.Our results showed that the GOF mutant R1 308 L would down-regulate the binding affinity of A1 to A2,leading to a low barrier in opening of the closed VWF-A structure.In contrast,the LOF mutant G1324S would enhance the stability of the closed VWF-A conformation by up-regulating the binding affinity of A1 to A2,leading to inhibition of VWF activity.
基金supported in part by the National Outstanding Youth Foundation of P.R.China (60525303)the National Natural Science Foundation of P.R.China(60404022,60604004)+2 种基金the Natural Science Foundation of Hebei Province (102160)the special projects in mathematics funded by the Natural Science Foundation of Hebei Province(07M005)the NS of Education Office in Hebei Province (2004123).
文摘The Newton-Like algorithm with price estimation error in optimization flow control in network is analyzed. The estimation error is treated as inexactness of the gradient and the inexact descent direction is analyzed. Based on the optimization theory, a sufficient condition for convergence of this algorithm with bounded price estimation error is obtained. Furthermore, even when this sufficient condition doesn't hold, this algorithm can also converge, provided a modified step size, and an attraction region is obtained. Based on Lasalle's invariance principle applied to a suitable Lyapunov function, the dynamic system described by this algorithm is proved to be global stability if the error is zero. And the Newton-Like algorithm with bounded price estimation error is also globally stable if the error satisfies the sufficient condition for convergence. All trajectories ultimately converge to the equilibrium point.
文摘In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generated by the state phase or its gradient(electronic current). The classical Shannon(S[p]) and Fisher(I[p]) information terms probe the entropic content of incoherent local events of the particle localization, embodied in the probability distribution p, while their nonclassical phase-companions, S[ Φ ] and I[ Φ ], provide relevant coherence information supplements.Thermodynamic-like couplings between the entropic and energetic descriptors of molecular states are shown to be precluded by the principles of quantum mechanics. The maximum of resultant entropy determines the phase-equilibrium state, defined by "thermodynamic" phase related to electronic density,which can be used to describe reactants in hypothetical stages of a bimolecular chemical reaction.Information channels of molecular systems and their entropic bond indices are summarized, the complete-bridge propagations are examined, and sequential cascades involving the complete sets of the atomic-orbital intermediates are interpreted as Markov chains. The QIT description is applied to reactive systems R = A―B, composed of the Acidic(A) and Basic(B) reactants. The electronegativity equalization processes are investigated and implications of the concerted patterns of electronic flows in equilibrium states of the complementarily arranged substrates are investigated. Quantum communications between reactants are explored and the QIT descriptors of the A―B bond multiplicity/composition are extracted.