We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation occurs between any two clusters of the same species and a reversible migration occurs simultaneously betw...We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation occurs between any two clusters of the same species and a reversible migration occurs simultaneously between two different species. For a simple model with constant aggregation rates and with the migration rates and , we find that the evolution behavior of the system depends crucially on the values of the indexes υ<SUB>1</SUB> and υ<SUB>2</SUB>. The aggregate size distribution of either species obeys a conventional scaling law for most cases. Moreover, we also generalize the two-species system to the multi-species case and analyze its kinetic behavior under the symmetrical conditions.展开更多
Two catalyzed-birth models of n-species (n ≥ 2) aggregates with exchange-driven growth processes are proposed and compared. In the first one, the exchange reaction occurs between any two aggregates Ak^m and Af^m of...Two catalyzed-birth models of n-species (n ≥ 2) aggregates with exchange-driven growth processes are proposed and compared. In the first one, the exchange reaction occurs between any two aggregates Ak^m and Af^m of the same species with the rate kernels Km(k,j)= Kmkj (m = 1, 2,... ,n, n ≥ 2), and aggregates of A^n species catalyze a monomer-birth of A^l species (l = 1, 2 , n - 1) with the catalysis rate kernel Jl(k,j) -Jlkj^v. The kinetic behaviors are investigated by means of the mean-field theory. We find that the evolution behavior of aggregate-size distribution ak^l(t) of A^l species depends crucially on the value of the catalysis rate parameter v: (i) ak^l(t) obeys the conventional scaling law in the case of v ≤ 0, (ii) ak^l(t) satisfies a modified scaling form in the case of v 〉 0. In the second model, the mechanism of monomer-birth of An-species catalyzed by A^l species is added on the basis of the first model, that is, the aggregates of A^l and A^n species catalyze each other to cause monomer-birth. The kinetic behaviors of A^l and A^n species are found to fall into two categories for the different v: (i) growth obeying conventional scaling form with v ≤ 0, (ii) gelling at finite time with v 〉 0.展开更多
Objective:To investigate the effect of electroacupuncture(EA)on cognitive function in D-galactose(D-gal)-induced aging rats,and the correlation between the effect and nucleotide-binding oligomerization domain(NOD)-lik...Objective:To investigate the effect of electroacupuncture(EA)on cognitive function in D-galactose(D-gal)-induced aging rats,and the correlation between the effect and nucleotide-binding oligomerization domain(NOD)-like receptor protein 3(NLRP3)-ASC-Caspase-1 signaling pathway.Methods:Forty-six male Sprague-Dawley(SD)rats were randomly divided into a control group(n=10),a model group(n=12),an EA-7 d group(n=12)and an EA-21 d group(n=12).Except the control group,the other three groups received 42 consecutive days of intraperitoneal injection of D-gal to establish aging rat models with cognitive dysfunction.The control group received the same amount of normal saline via intraperitoneal injection.Two EA groups were given EA therapy for 21 consecutive days(began from the 22nd day of modeling)or 7 consecutive days(began from the 36th day of modeling)accordingly at Dazhui(GV 14),Baihui(GV 20),Shenshu(BL 23)and Zusanli(ST 36).After modeling/intervention,all four groups received behavioral evaluations by Morris water maze(MWM)test,novel object recognition(NOR)test and step-down passive avoidance(SDPA)test followed by the Western blot(WB)detection of the expression levels of hippocampal NLRP3 inflammasome-associated proteins NLRP3,ASC and Caspase-1.Results:MWM(place navigation test,PNT)results showed that the escape latency in the model group was significantly longer than that in the other three groups(P<0.05),and there was no significant difference among the other three groups on the 1st day of the test(P>0.05).From the 2nd day to the 4th day of the test,there was no significant difference between the EA-21 d group and the control group(P>0.05)in the escape latency;the escape latency was significantly shorter in the EA-21 d group than in the model group and the EA-7 d group(P<0.05).MWM(spatial probe test,SPT)results showed that the time spent in the target quadrant was significantly shorter and platform crossover number was significantly lower in the model group than in the other three groups(P<0.05).The time spent in the target quadrant was longer in the EA-7 d group than in the model group(P<0.05),but was shorter than that in the control group and the EA-21 d group(P<0.05).There was no significant difference in the swimming speed among the four groups(P>0.05).NOR results showed that there was no significant difference in the recognition ratio between the EA-7 d group and the EA-21 d group(P>0.05),and the recognition ratio was significantly higher in the two EA groups than in the model group(P<0.05),but was lower than in the control group(P<0.05).SDPA results showed that the electric shock number was higher in the model group than in the other three groups(P<0.05),and the differences among the other three groups were statistically insignificant(P>0.05).The model group had the shortest step-down latency,followed by the EA-7 d group,the EA-21 d group and the control group in order(P<0.05).The WB results indicated that the expression level of NLRP3 was significantly lower in the control group and the EA-21 d group than in the model group and the EA-7 d group(P<0.05).The expression levels of ASC and Caspase-1 were significantly higher in the model group than in the other three groups(P<0.05),and there was no significant difference among these three groups(P>0.05).Conclusion:NLRP3 inflammasome may be involved in the development of cognitive decline in aging rats;7 consecutive days of EA intervention can partially improve the cognitive impairment in aging rats though the effect is rather limited;21 consecutive days of EA intervention may improve the learning and memory abilities in aging rats via downregulating the expression levels of NLRP3 inflammasome-associated proteins in hippocampus.展开更多
文摘We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation occurs between any two clusters of the same species and a reversible migration occurs simultaneously between two different species. For a simple model with constant aggregation rates and with the migration rates and , we find that the evolution behavior of the system depends crucially on the values of the indexes υ<SUB>1</SUB> and υ<SUB>2</SUB>. The aggregate size distribution of either species obeys a conventional scaling law for most cases. Moreover, we also generalize the two-species system to the multi-species case and analyze its kinetic behavior under the symmetrical conditions.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10275048 and 10305009 and the Natural Science Foundation of Zhejiang Province of China under Grant No. 102067
文摘Two catalyzed-birth models of n-species (n ≥ 2) aggregates with exchange-driven growth processes are proposed and compared. In the first one, the exchange reaction occurs between any two aggregates Ak^m and Af^m of the same species with the rate kernels Km(k,j)= Kmkj (m = 1, 2,... ,n, n ≥ 2), and aggregates of A^n species catalyze a monomer-birth of A^l species (l = 1, 2 , n - 1) with the catalysis rate kernel Jl(k,j) -Jlkj^v. The kinetic behaviors are investigated by means of the mean-field theory. We find that the evolution behavior of aggregate-size distribution ak^l(t) of A^l species depends crucially on the value of the catalysis rate parameter v: (i) ak^l(t) obeys the conventional scaling law in the case of v ≤ 0, (ii) ak^l(t) satisfies a modified scaling form in the case of v 〉 0. In the second model, the mechanism of monomer-birth of An-species catalyzed by A^l species is added on the basis of the first model, that is, the aggregates of A^l and A^n species catalyze each other to cause monomer-birth. The kinetic behaviors of A^l and A^n species are found to fall into two categories for the different v: (i) growth obeying conventional scaling form with v ≤ 0, (ii) gelling at finite time with v 〉 0.
文摘Objective:To investigate the effect of electroacupuncture(EA)on cognitive function in D-galactose(D-gal)-induced aging rats,and the correlation between the effect and nucleotide-binding oligomerization domain(NOD)-like receptor protein 3(NLRP3)-ASC-Caspase-1 signaling pathway.Methods:Forty-six male Sprague-Dawley(SD)rats were randomly divided into a control group(n=10),a model group(n=12),an EA-7 d group(n=12)and an EA-21 d group(n=12).Except the control group,the other three groups received 42 consecutive days of intraperitoneal injection of D-gal to establish aging rat models with cognitive dysfunction.The control group received the same amount of normal saline via intraperitoneal injection.Two EA groups were given EA therapy for 21 consecutive days(began from the 22nd day of modeling)or 7 consecutive days(began from the 36th day of modeling)accordingly at Dazhui(GV 14),Baihui(GV 20),Shenshu(BL 23)and Zusanli(ST 36).After modeling/intervention,all four groups received behavioral evaluations by Morris water maze(MWM)test,novel object recognition(NOR)test and step-down passive avoidance(SDPA)test followed by the Western blot(WB)detection of the expression levels of hippocampal NLRP3 inflammasome-associated proteins NLRP3,ASC and Caspase-1.Results:MWM(place navigation test,PNT)results showed that the escape latency in the model group was significantly longer than that in the other three groups(P<0.05),and there was no significant difference among the other three groups on the 1st day of the test(P>0.05).From the 2nd day to the 4th day of the test,there was no significant difference between the EA-21 d group and the control group(P>0.05)in the escape latency;the escape latency was significantly shorter in the EA-21 d group than in the model group and the EA-7 d group(P<0.05).MWM(spatial probe test,SPT)results showed that the time spent in the target quadrant was significantly shorter and platform crossover number was significantly lower in the model group than in the other three groups(P<0.05).The time spent in the target quadrant was longer in the EA-7 d group than in the model group(P<0.05),but was shorter than that in the control group and the EA-21 d group(P<0.05).There was no significant difference in the swimming speed among the four groups(P>0.05).NOR results showed that there was no significant difference in the recognition ratio between the EA-7 d group and the EA-21 d group(P>0.05),and the recognition ratio was significantly higher in the two EA groups than in the model group(P<0.05),but was lower than in the control group(P<0.05).SDPA results showed that the electric shock number was higher in the model group than in the other three groups(P<0.05),and the differences among the other three groups were statistically insignificant(P>0.05).The model group had the shortest step-down latency,followed by the EA-7 d group,the EA-21 d group and the control group in order(P<0.05).The WB results indicated that the expression level of NLRP3 was significantly lower in the control group and the EA-21 d group than in the model group and the EA-7 d group(P<0.05).The expression levels of ASC and Caspase-1 were significantly higher in the model group than in the other three groups(P<0.05),and there was no significant difference among these three groups(P>0.05).Conclusion:NLRP3 inflammasome may be involved in the development of cognitive decline in aging rats;7 consecutive days of EA intervention can partially improve the cognitive impairment in aging rats though the effect is rather limited;21 consecutive days of EA intervention may improve the learning and memory abilities in aging rats via downregulating the expression levels of NLRP3 inflammasome-associated proteins in hippocampus.