The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivativ...The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivative operator.Additionally,time delays in the potential field force and coupling force transmission are both considered.Firstly,based on the delay decoupling formula,combined with statistical mean method and the fractional-order Shapiro–Loginov formula,the“statistic synchronization”among particles is obtained,revealing the statistical equivalence between the mean field behavior of the system and the behavior of individual particles.Due to the existence of the coupling delay,the impact of the coupling force on synchronization exhibits non-monotonic,which is different from the previous monotonic effects.Then,two kinds of theoretical expression of output amplitude gains G and G are derived by time-delay decoupling formula and small delay approximation theorem,respectively.Compared to G,G is an exact theoretical solution,which means that G is not only more accurate in the region of small delay,but also applies to the region of large delay.Finally,the study of the output amplitude gain G and its resonance behavior are explored.Due to the presence of the potential field delay,a new resonance phenomenon termed“periodic resonance”is discovered,which arises from the periodic matching between the potential field delay and the driving frequency.This resonance phenomenon is analyzed qualitatively and quantitatively,uncovering undiscovered characteristics in previous studies.展开更多
To test the hypothesis that latency delay in the fellow eyes of optic neuritis(ON) patients and to compensate for delayed transmission of visual information, latency change of multi-focal visual evoked potential(mf...To test the hypothesis that latency delay in the fellow eyes of optic neuritis(ON) patients and to compensate for delayed transmission of visual information, latency change of multi-focal visual evoked potential(mf VEP) traces in fellow eyes of 15 ON patients were analyzed. Patients with low risk(LR) for developing multiple sclerosis(MS) were examined separately from MS patients to isolate effect of cortical plasticity from potential pathological changes in disseminated disease. The small increase in latency in fellow eyes of LR group was statistically not significant. In MS patients, the latency was significantly delayed(P〈0.02). The magnitude of the latency change in the fellow eyes did not correlate with the severity of latency delay in the affected eyes(R^2〈0.02, P=0.3). The differences between ON patients with and without MS, reported here, suggest that the presence of disseminated disease plays critical role in latency delay of the fellow eye.展开更多
Welan gum is widely applied in environmental admixtures due to its good thickening and rheological properties. With its powerful charge density in the molecular structure, the competitive adsorption between welan gum ...Welan gum is widely applied in environmental admixtures due to its good thickening and rheological properties. With its powerful charge density in the molecular structure, the competitive adsorption between welan gum and other admixtures happened remarkably during the addition process. So controlling the releasing rate of welan gum will be able to improve the competitive adsorption, while having no disadvantages to its thickening and workability at the same time. The investigation of influences of the delay released welan gum(DRWG) on the fluidity and strength of cement mortar, bleeding rate and rheological properties of cement paste, adsorption amount and zeta potential of clinker single mineralogical phases, shows that there will be a better mortar workability and certain improvement in mortar strength with DRWG. For mortar with DRWG, the standing bleeding rate is 0, and there is less thixotropic, less adsorption, and a lower zeta potential value on the surface of clinker mineralogical phases.展开更多
Objective To investigate changes in the delayed rectifier K + channel (Kv) function and the regulation of Kv by the protein kinase C (PKC) pathway in bronchial myocytes from asthmatic rats. Methods The Kv currents an...Objective To investigate changes in the delayed rectifier K + channel (Kv) function and the regulation of Kv by the protein kinase C (PKC) pathway in bronchial myocytes from asthmatic rats. Methods The Kv currents and membrane potentials in bronchial myocytes from asthmatic rats and from controls were observed, using whole cell voltage- and current-patch clamp techniques.Results Bronchial myocytes from asthmatic rats showed a significant reduction in Kv-current density (51.6±9.4 pA/pF, n=14, P<0.01) in comparison with those from control rats (72.4±12.3 pA/pF, n=14) at +50 mV. The current-voltage relationship curve exhibited a significant downward shift. Bronchial myocytes from asthmatic rats had no significantly different capacitances (P>0.05), but had more positive membrane potential ( P<0.01) compared with those from controls. 1 μmol/L phorbol 12-myristate 13-acetate, a PKC activator, caused an obvious reduction in Kv-current density (P<0.01) and a significant downward shift in the current-voltage relationship curve, an effect which was partly abolished by 1 μmol/L Ro31-8220 (a PKC inhibitor); 1 μmol/L phorbol 12-myristate 13-acetate caused more positive membrane potential (Em), from -36.8±5.7 mV to -30.4±7.3 mV, in rat bronchial myocytes (P<0.05). This effect was partly abolished by 1 μmol/L Ro31-8220. Conclusions Bronchial myocytes from asthmatic rats have inhibited Kv function, more positive membrane potential, and higher excitability, all of which can also be induced by PKC activation. These characteristics may contribute to the development of airway hyperreactivity in asthma.展开更多
基金supported by the Natural Science Foundation of Sichuan Province,China(Youth Science Foundation)(Grant No.2022NSFSC1952).
文摘The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivative operator.Additionally,time delays in the potential field force and coupling force transmission are both considered.Firstly,based on the delay decoupling formula,combined with statistical mean method and the fractional-order Shapiro–Loginov formula,the“statistic synchronization”among particles is obtained,revealing the statistical equivalence between the mean field behavior of the system and the behavior of individual particles.Due to the existence of the coupling delay,the impact of the coupling force on synchronization exhibits non-monotonic,which is different from the previous monotonic effects.Then,two kinds of theoretical expression of output amplitude gains G and G are derived by time-delay decoupling formula and small delay approximation theorem,respectively.Compared to G,G is an exact theoretical solution,which means that G is not only more accurate in the region of small delay,but also applies to the region of large delay.Finally,the study of the output amplitude gain G and its resonance behavior are explored.Due to the presence of the potential field delay,a new resonance phenomenon termed“periodic resonance”is discovered,which arises from the periodic matching between the potential field delay and the driving frequency.This resonance phenomenon is analyzed qualitatively and quantitatively,uncovering undiscovered characteristics in previous studies.
基金Supported by Save Neuron Grant(Novartis)Grants from Biogen Idec,Sydney Eye Hospital FoundationKing Saud University
文摘To test the hypothesis that latency delay in the fellow eyes of optic neuritis(ON) patients and to compensate for delayed transmission of visual information, latency change of multi-focal visual evoked potential(mf VEP) traces in fellow eyes of 15 ON patients were analyzed. Patients with low risk(LR) for developing multiple sclerosis(MS) were examined separately from MS patients to isolate effect of cortical plasticity from potential pathological changes in disseminated disease. The small increase in latency in fellow eyes of LR group was statistically not significant. In MS patients, the latency was significantly delayed(P〈0.02). The magnitude of the latency change in the fellow eyes did not correlate with the severity of latency delay in the affected eyes(R^2〈0.02, P=0.3). The differences between ON patients with and without MS, reported here, suggest that the presence of disseminated disease plays critical role in latency delay of the fellow eye.
基金Funded by the National Natural Science Foundation of China(No.51202173)
文摘Welan gum is widely applied in environmental admixtures due to its good thickening and rheological properties. With its powerful charge density in the molecular structure, the competitive adsorption between welan gum and other admixtures happened remarkably during the addition process. So controlling the releasing rate of welan gum will be able to improve the competitive adsorption, while having no disadvantages to its thickening and workability at the same time. The investigation of influences of the delay released welan gum(DRWG) on the fluidity and strength of cement mortar, bleeding rate and rheological properties of cement paste, adsorption amount and zeta potential of clinker single mineralogical phases, shows that there will be a better mortar workability and certain improvement in mortar strength with DRWG. For mortar with DRWG, the standing bleeding rate is 0, and there is less thixotropic, less adsorption, and a lower zeta potential value on the surface of clinker mineralogical phases.
基金ThisstudywassupportedbytheNationalNaturalScienceFoundationofChina (No 3 0 2 70 5 83 ) .
文摘Objective To investigate changes in the delayed rectifier K + channel (Kv) function and the regulation of Kv by the protein kinase C (PKC) pathway in bronchial myocytes from asthmatic rats. Methods The Kv currents and membrane potentials in bronchial myocytes from asthmatic rats and from controls were observed, using whole cell voltage- and current-patch clamp techniques.Results Bronchial myocytes from asthmatic rats showed a significant reduction in Kv-current density (51.6±9.4 pA/pF, n=14, P<0.01) in comparison with those from control rats (72.4±12.3 pA/pF, n=14) at +50 mV. The current-voltage relationship curve exhibited a significant downward shift. Bronchial myocytes from asthmatic rats had no significantly different capacitances (P>0.05), but had more positive membrane potential ( P<0.01) compared with those from controls. 1 μmol/L phorbol 12-myristate 13-acetate, a PKC activator, caused an obvious reduction in Kv-current density (P<0.01) and a significant downward shift in the current-voltage relationship curve, an effect which was partly abolished by 1 μmol/L Ro31-8220 (a PKC inhibitor); 1 μmol/L phorbol 12-myristate 13-acetate caused more positive membrane potential (Em), from -36.8±5.7 mV to -30.4±7.3 mV, in rat bronchial myocytes (P<0.05). This effect was partly abolished by 1 μmol/L Ro31-8220. Conclusions Bronchial myocytes from asthmatic rats have inhibited Kv function, more positive membrane potential, and higher excitability, all of which can also be induced by PKC activation. These characteristics may contribute to the development of airway hyperreactivity in asthma.