The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regenerat...The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regeneration of PAN-ACF was also studied.Freundlich and Dubinin-Radushkevich(D-R) adsorption equations can well describe the adsorption isotherm.CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion.The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model,and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model.The ACF can be recycled through thermal regeneration,whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration.78%-94%of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale,which confirms the efficacy of ACF under industrial conditions.The results indicate that PAN-ACF is applicable to CT removal from wastewater.展开更多
Since the discovery of the tetracycline in 1953, numerous natural andsemisynthelic tetracyclines have been reported with broad spectrum antibacterial activity .Doxycycline 1 and minocycline 2 are semisyn-thetic second...Since the discovery of the tetracycline in 1953, numerous natural andsemisynthelic tetracyclines have been reported with broad spectrum antibacterial activity .Doxycycline 1 and minocycline 2 are semisyn-thetic second-generation tetracyclines that exertanti-inflammatory effects. These effects appear completely separate and distinct fromtheirantimicrobial actio. Minocycline and doxycycline are absorbed rapidly and show higher brainpenetrability than other tetracyclines. During recent years, doxycycline and minocycline have shownto have neuroprotective effects in models of global and focal ischemia . The neuroprotective effectsare assumed to result from the inhibition of microglia activation. Furthermore, from an in vitrostudy, it was reported that minocycline induces neuroprotection against NMDA-induced neurotoxicityby inhibiting p38 MAP ki-nase activity in microglia . However, neuroprotective mechanisms andstructure-activity relationships of these compounds in neurons are unclear.展开更多
A method based on cumulative prospect theory was proposed to solve risky multiple attribute decision making problems with Four -dimensional reference points. Considering the influence of different learning processes a...A method based on cumulative prospect theory was proposed to solve risky multiple attribute decision making problems with Four -dimensional reference points. Considering the influence of different learning processes and corresponding features on decision-making, a new reference-learning behavior is added, and a risk-based multiple-attribute decision-making method based on four-dimensional reference point cumulative prospect theory is proposed. Firstly, according to the cumulative prospect theory, the prospect value and the decision function value of the four reference points of learning, time, evaluation value and expected value are calculated respectively, and the cumulative prospect value matrix of each program dynamic is formed. Secondly,according to the WAA operalor, Maximize the stage weighting model to obtain the integrated cumulative prospect value. Finally, on the basis of this, the alternatives are sorted according to the size of the total cumulative prospect value, and compared with other methods, the validity and scientific of the proposed method are proved.展开更多
AIM:To investigate the protective effects of melatonin on carbon tetrachloride(CCl4)-induced hepatic fibrosis in experimental rats.METHODS:All rats were randomly divided into normal control group,model control group t...AIM:To investigate the protective effects of melatonin on carbon tetrachloride(CCl4)-induced hepatic fibrosis in experimental rats.METHODS:All rats were randomly divided into normal control group,model control group treated with CCl4 for 12 wk,CCl4+NAC group treated with CCl4+NAC(100 mg/kg,i.p.)for 12 wk,CCl4+MEL-1 group treated with CCl4+melatonin(2.5 mg/kg)for 12 wk,CCl4+MEL-2 group treated with CCl4+ melatonin(5.0 mg/kg)for 12 wk,and CCl4+MEL-3 group treated with CCl4+melatonin(10 mg/kg).Rats in the treatment groups were injected subcutaneously with sterile CCl4(3 mL/kg,body weight)in a ratio of 2:3 with olive oil twice a week.Rats in normal control group received hypodermic injection of olive oil at the same dose and frequency as those in treatment groups.At the end of experiment,rats in each group were anesthetized and sacrificed.Hematoxylin and eosin(HE)staining and Van Gieson staining were used to examine changes in liver pathology.Serum activities of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and protein concentration weremeasured with routine laboratory methods using an autoanalyzer.Hydroxyproline(HYP)content in liver and malondialdehyde(MDA)and glutathione peroxidase(GPx)levels in liver homogenates were assayed by spectrophotometry.Serum hyaluronic acid(HA),laminin(LN),and procollagenⅢN-terminal peptide(PⅢNP)were determined by radioimmunoassay.RESULTS:Pathologic grading showed that the fibrogenesis was much less severe in CCl4+MEL3 group than in model control group(u=2.172,P<0.05),indicating that melatonin(10 mg/kg)can significantly ameliorate CCl4-induced hepatic fibrotic changes.The serum levels of ALT and AST were markedly lower in CCl4+MEL treatment groups(5,10 mg/kg)than in model control group(ALT:286.23 ±121.91 U/L vs 201.15±101.16 U/L and 178.67 ±103.14 U/L,P=0.028,P=0.007;AST:431.00 ±166.35 U/L vs 321.23±162.48 U/L and 292.42 ±126.23 U/L,P=0.043,P=0.013).Similarly,the serum laminin(LN)and hyaluronic acid(HA)levels and hydroxyproline(HYP)contents in liver were significantly lower in CCl4+MEL-3 group(10 mg/kg)than in model control group(LN:45.89±11.71μg/L vs 55.26± 12.30μg/L,P=0.012;HA:135.71±76.03μg/L vs 201.10±68.46μg/L,P=0.020;HYP:0.42±0.08 mg/g tissue vs 0.51±0.07 mg/g tissue,P=0.012).Moreover,treatment with melatonin(5,10 mg/kg)significantly reduced the MDA content and increased the GPx activity in liver homogenates compared with model control group(MDA:7.89±1.49 noml/mg prot vs 6.29±1.42 noml/mg prot and 6.25±2.27 noml/mg prot,respectively,P=0.015,P=0.015;GPx:49.13± 8.72 U/mg prot vs 57.38±7.65 U/mg prot and 61.39± 13.15 U/mg prot,respectively,P=0.035,P=0.003).CONCLUSION:Melatonin can ameliorate CCl4-induced hepatic fibrosis in rats.The protective effect of melatonin on hepatic fibrosis may be related to its antioxidant activities.展开更多
This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which...This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which shall hereafter be referred to as the NC-DRP-4DVar. A preliminary test is conducted using the Lorenz-96 model in one single-window experiment and several multiple-window experiments. The results of the single-window experiment show that compared with the adjoint-based traditional 4DVar, the final convergence of the cost function for the NC-DRP-4DVar is almost the same as that using the traditional 4DVar, but with much less computation. Furthermore, the 30-window assimilation experiments demonstrate that the NC-DRP-4DVar can alleviate the linearity approximation error and reduce the root mean square error significantly.展开更多
This paper considers the following Cauchy problem for semilinear wave equations in n space dimensionswhere A is the wave operator, F is quadratic in (?) with (?) = ( ).The minimal value of s is determined such that th...This paper considers the following Cauchy problem for semilinear wave equations in n space dimensionswhere A is the wave operator, F is quadratic in (?) with (?) = ( ).The minimal value of s is determined such that the above Cauchy problem is locally well-posed in H8. It turns out that for the general equation s must satisfyThis is due to Ponce and Sideris (when n = 3) and Tataru (when n≥5). The purpose of this paper is to supplement with a proof in the case n = 2,4.展开更多
We show that if the fiber of a closed 4-dimensional mapping torus X is reducible and not S2× S1 or RP3#P3, then the virtual first Betti number of X is infinite and X is not virtually symplectic. This confirms two...We show that if the fiber of a closed 4-dimensional mapping torus X is reducible and not S2× S1 or RP3#P3, then the virtual first Betti number of X is infinite and X is not virtually symplectic. This confirms two conjectures made by Li and Ni （2014） in an earlier paper.展开更多
基金Project(2004C33068) supported by the Science and Technology Programs of Zhejiang Province,ChinaProject(20100933B17) supported by the Social Development and Science Research Program of Hangzhou,China
文摘The isotherm,mechanism and kinetics of carbon tetrachloride(CT) adsorption by polyacrylonitrile-based activated carbon fiber(PAN-ACF) were investigated in batch reactors and a continuous flow reactor,and the regeneration of PAN-ACF was also studied.Freundlich and Dubinin-Radushkevich(D-R) adsorption equations can well describe the adsorption isotherm.CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion.The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model,and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model.The ACF can be recycled through thermal regeneration,whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration.78%-94%of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale,which confirms the efficacy of ACF under industrial conditions.The results indicate that PAN-ACF is applicable to CT removal from wastewater.
文摘Since the discovery of the tetracycline in 1953, numerous natural andsemisynthelic tetracyclines have been reported with broad spectrum antibacterial activity .Doxycycline 1 and minocycline 2 are semisyn-thetic second-generation tetracyclines that exertanti-inflammatory effects. These effects appear completely separate and distinct fromtheirantimicrobial actio. Minocycline and doxycycline are absorbed rapidly and show higher brainpenetrability than other tetracyclines. During recent years, doxycycline and minocycline have shownto have neuroprotective effects in models of global and focal ischemia . The neuroprotective effectsare assumed to result from the inhibition of microglia activation. Furthermore, from an in vitrostudy, it was reported that minocycline induces neuroprotection against NMDA-induced neurotoxicityby inhibiting p38 MAP ki-nase activity in microglia . However, neuroprotective mechanisms andstructure-activity relationships of these compounds in neurons are unclear.
文摘A method based on cumulative prospect theory was proposed to solve risky multiple attribute decision making problems with Four -dimensional reference points. Considering the influence of different learning processes and corresponding features on decision-making, a new reference-learning behavior is added, and a risk-based multiple-attribute decision-making method based on four-dimensional reference point cumulative prospect theory is proposed. Firstly, according to the cumulative prospect theory, the prospect value and the decision function value of the four reference points of learning, time, evaluation value and expected value are calculated respectively, and the cumulative prospect value matrix of each program dynamic is formed. Secondly,according to the WAA operalor, Maximize the stage weighting model to obtain the integrated cumulative prospect value. Finally, on the basis of this, the alternatives are sorted according to the size of the total cumulative prospect value, and compared with other methods, the validity and scientific of the proposed method are proved.
基金Supported by The Natural Science Foundation of Anhui Province No.01043904the Natural Science Research Project of Colleges and Universities of Anhui Province No.KJ2007B146
文摘AIM:To investigate the protective effects of melatonin on carbon tetrachloride(CCl4)-induced hepatic fibrosis in experimental rats.METHODS:All rats were randomly divided into normal control group,model control group treated with CCl4 for 12 wk,CCl4+NAC group treated with CCl4+NAC(100 mg/kg,i.p.)for 12 wk,CCl4+MEL-1 group treated with CCl4+melatonin(2.5 mg/kg)for 12 wk,CCl4+MEL-2 group treated with CCl4+ melatonin(5.0 mg/kg)for 12 wk,and CCl4+MEL-3 group treated with CCl4+melatonin(10 mg/kg).Rats in the treatment groups were injected subcutaneously with sterile CCl4(3 mL/kg,body weight)in a ratio of 2:3 with olive oil twice a week.Rats in normal control group received hypodermic injection of olive oil at the same dose and frequency as those in treatment groups.At the end of experiment,rats in each group were anesthetized and sacrificed.Hematoxylin and eosin(HE)staining and Van Gieson staining were used to examine changes in liver pathology.Serum activities of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and protein concentration weremeasured with routine laboratory methods using an autoanalyzer.Hydroxyproline(HYP)content in liver and malondialdehyde(MDA)and glutathione peroxidase(GPx)levels in liver homogenates were assayed by spectrophotometry.Serum hyaluronic acid(HA),laminin(LN),and procollagenⅢN-terminal peptide(PⅢNP)were determined by radioimmunoassay.RESULTS:Pathologic grading showed that the fibrogenesis was much less severe in CCl4+MEL3 group than in model control group(u=2.172,P<0.05),indicating that melatonin(10 mg/kg)can significantly ameliorate CCl4-induced hepatic fibrotic changes.The serum levels of ALT and AST were markedly lower in CCl4+MEL treatment groups(5,10 mg/kg)than in model control group(ALT:286.23 ±121.91 U/L vs 201.15±101.16 U/L and 178.67 ±103.14 U/L,P=0.028,P=0.007;AST:431.00 ±166.35 U/L vs 321.23±162.48 U/L and 292.42 ±126.23 U/L,P=0.043,P=0.013).Similarly,the serum laminin(LN)and hyaluronic acid(HA)levels and hydroxyproline(HYP)contents in liver were significantly lower in CCl4+MEL-3 group(10 mg/kg)than in model control group(LN:45.89±11.71μg/L vs 55.26± 12.30μg/L,P=0.012;HA:135.71±76.03μg/L vs 201.10±68.46μg/L,P=0.020;HYP:0.42±0.08 mg/g tissue vs 0.51±0.07 mg/g tissue,P=0.012).Moreover,treatment with melatonin(5,10 mg/kg)significantly reduced the MDA content and increased the GPx activity in liver homogenates compared with model control group(MDA:7.89±1.49 noml/mg prot vs 6.29±1.42 noml/mg prot and 6.25±2.27 noml/mg prot,respectively,P=0.015,P=0.015;GPx:49.13± 8.72 U/mg prot vs 57.38±7.65 U/mg prot and 61.39± 13.15 U/mg prot,respectively,P=0.035,P=0.003).CONCLUSION:Melatonin can ameliorate CCl4-induced hepatic fibrosis in rats.The protective effect of melatonin on hepatic fibrosis may be related to its antioxidant activities.
基金supported by the National Basic Research Program of China (973 Program, Grant No. 2010CB951604)the National Key Technologies Research and Development Program of China (Grant No. 2012BAC22B02)the National Natural Science Foundation of China (Grant No. 41105120)
文摘This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which shall hereafter be referred to as the NC-DRP-4DVar. A preliminary test is conducted using the Lorenz-96 model in one single-window experiment and several multiple-window experiments. The results of the single-window experiment show that compared with the adjoint-based traditional 4DVar, the final convergence of the cost function for the NC-DRP-4DVar is almost the same as that using the traditional 4DVar, but with much less computation. Furthermore, the 30-window assimilation experiments demonstrate that the NC-DRP-4DVar can alleviate the linearity approximation error and reduce the root mean square error significantly.
基金Project supported by the 973 Project of the National Natural Science Foundation of China,the Key Teachers Program and the Doctoral Program Foundation ofthe Miistry of Education of China.
文摘This paper considers the following Cauchy problem for semilinear wave equations in n space dimensionswhere A is the wave operator, F is quadratic in (?) with (?) = ( ).The minimal value of s is determined such that the above Cauchy problem is locally well-posed in H8. It turns out that for the general equation s must satisfyThis is due to Ponce and Sideris (when n = 3) and Tataru (when n≥5). The purpose of this paper is to supplement with a proof in the case n = 2,4.
基金supported by National Science Foundation of USA(Grant No.DMS1252992)an Alfred P.Sloan Research Fellowship
文摘We show that if the fiber of a closed 4-dimensional mapping torus X is reducible and not S2× S1 or RP3#P3, then the virtual first Betti number of X is infinite and X is not virtually symplectic. This confirms two conjectures made by Li and Ni （2014） in an earlier paper.
