In the present paper, a numerical modeling was developed to simulate the growth kinetics of ferrite transformed from austenite in Fe-C-∑X (X denotes substitution elements, such as Mn, Ni, Cr etc.) steels by solving...In the present paper, a numerical modeling was developed to simulate the growth kinetics of ferrite transformed from austenite in Fe-C-∑X (X denotes substitution elements, such as Mn, Ni, Cr etc.) steels by solving the diffusion equation using finite difference method (FDM). Coupled with the kinetic modeling, thermodynamic calculations were carried out to determine the γ/α phase equilibrium conditions using a para-equilibrium (PE) model. The dissipation of free energy for γ→α phase transformation due to the so-called solute drag effect (SDE) was taken into account in the thermodynamic modeling. With this modeling, simulations on the growth kinetics of ferrite in the steels containing austenite-stabilizing and ferrite-stabilizing elements (such as Ni, Mn and Si, Cr, respectively) were performed, which indicates that it deviates from the parabolic growth rate law after the initial stage of transformation. The results were compared with the experimental values given by Bradley and Aaronson, showing that this model has a reasonably good accuracy to predict the growth kinetics of ferrite.展开更多
Background and objective Maintenance of genomic integrity is essential to ensure normal organismal development and to prevent diseases such as cancer.PR-Set7(also known as Set8)is a cell cycle regulated enzyme that ca...Background and objective Maintenance of genomic integrity is essential to ensure normal organismal development and to prevent diseases such as cancer.PR-Set7(also known as Set8)is a cell cycle regulated enzyme that catalyses monomethylation of histone 4 at Lys20(H4K20me1)to promote chromosome condensation and prevent DNA damage.Recent studies show that CRL4CDT2-mediated ubiquitylation of PR-Set7 leads to its degradation during S phase and after DNA damage.This might occur to ensure appropriate changes in chromosome structure during the cell cycle or to preserve genome integrity after DNA damage.Methods We developed a new model of lung tumor development in mice harboring a conditionally expressed allele of Cul4A.We have therefore used a mouse model to demonstrate for the first time that Cul4A is oncogenic in vivo.With this model,staining of PR-Set7 in the preneoplastic and tumor lesions in Adeno Cre-induced mouse lungs was performed.Meanwhile we identified higher protein level changes ofγ-tubulin and pericentrin by IHC.Results The level of PR-Set7 down-regulated in the preneoplastic and adenocarcinomous lesions following over-expression of Cul4A.We also identified higher levels of the proteins pericentrin andγ-tubulin in Cul4A mouse lungs induced by Adeno Cre.Conclusion PR-Set7 is a direct target of Cul4A for degradation and involved in the formation of lung tumors in the conditional Cul4A transgenic mouse model.展开更多
A calculation formula of ln γ i 0 for solute element i in liquid alloys was derived by use of free volume theory and Miedema formation enthalpy model. The values of ln γ i 0 of solute elements in liqui...A calculation formula of ln γ i 0 for solute element i in liquid alloys was derived by use of free volume theory and Miedema formation enthalpy model. The values of ln γ i 0 of solute elements in liquid copper at 1273 K were obtained. The results obtained show that the coincidence rate of sign (positive or negative) was 90% for the calculated and experimental values, which were basically in the same magnitude.展开更多
AIM To establish a rat model of anxiety-like gastric hyper-sensitivity(GHS) of functional dyspepsia(FD) induced by novel sequential stress.METHODS Animal pups were divided into two groups from postnatal day 2: control...AIM To establish a rat model of anxiety-like gastric hyper-sensitivity(GHS) of functional dyspepsia(FD) induced by novel sequential stress.METHODS Animal pups were divided into two groups from postnatal day 2: controls and the sequential-stress-treated. The sequential-stress-treated group received maternal separation and acute gastric irritation early in life and restraint stress in adulthood; controls were reared undisturbed with their mothers. Rats in both groups were followed to adulthood(8 wk) at which point the anxietylike behaviors and visceromotor responses to gastric distention(20-100 mm Hg) and gastric emptying were tested. Meanwhile, alterations in several anxiety-related brain-stomach modulators including 5-hydroxytryptamine(5-HT), γ-aminobutyric acid(GABA), brain-derived neurotrophic factor(BDNF) and nesfatin-1 in the rat hippocampus, plasma and gastric fundus and the 5-HT1 A receptor(5-HT1 AR) in the hippocampal CA1 subfield and the mucosa of the gastric fundus were examined.RESULTS Sequential-stress-treated rats simultaneously demonstrated anxiety-like behaviors and GHS in dose-dependent manner compared with the control group. Although rats in both groups consumed similar amount of solid food, the rate of gastric emptying was lower in the sequentialstress-treated rats than in the control group. Sequential stress significantly decreased the levels of 5-HT(51.91 ± 1.88 vs 104.21 ± 2.88, P < 0.01), GABA(2.38 ± 0.16 vs 5.01 ± 0.13, P < 0.01) and BDNF(304.40 ± 10.16 vs 698.17 ± 27.91, P < 0.01) in the hippocampus but increased the content of nesfatin-1(1961.38 ± 56.89 vs 1007.50 ± 33.05, P < 0.01) in the same site; significantly decreased the levels of 5-HT(47.82 ± 2.29 vs 89.45 ± 2.61, P < 0.01) and BDNF(257.05 ± 12.89 vs 536.71 ± 20.73, P < 0.01) in the plasma but increased the content of nesfatin-1 in it(1391.75 ± 42.77 vs 737.88 ± 33.15, P < 0.01); significantly decreased the levels of 5-HT(41.15 ± 1.81 vs 89.17 ± 2.31, P < 0.01) and BDNF(226.49 ± 12.10 vs 551.36 ± 16.47, P < 0.01) in the gastric fundus but increased the content of nesfatin-1 in the same site(1534.75 ± 38.52 vs 819.63 ± 38.04, P < 0.01). The expressions of 5-HT1 AR in the hippocampal CA1 subfield and the mucosa of the gastric fundus were down-regulated measured by IHC(Optical Density value: Hippocampus 15253.50 ± 760.35 vs 21149.75 ± 834.13; gastric fundus 15865.25 ± 521.24 vs 23865.75 ± 1868.60; P < 0.05, respectively) and WB(0.38 ± 0.01 vs 0.57 ± 0.03, P < 0.01)(n = 8 in each group). CONCLUSION Sequential stress could induce a potential rat model of anxiety-like GHS of FD, which could be used to research the mechanisms of this intractable disease.展开更多
Simulation code for a model of the adaptive immune response seen in flavivirus infections is used to explain the immunopathological consequences seen in West Nile Virus virus (WNV) infections. We use a model that spec...Simulation code for a model of the adaptive immune response seen in flavivirus infections is used to explain the immunopathological consequences seen in West Nile Virus virus (WNV) infections. We use a model that specifically handles the differences in how the virus infects resting cells, the G0 state, versus dividing cells, the G1 state, which includes vastly increased MHC-I upregulation for resting cells over dividing cells. The simulation suggests how the infection progresses in a one host model and the results shed insight into the unusual survival curve data obtained for this infection: there is an increase in health even though viral load has increased.展开更多
基金supported by the National Natural Sci-ence Foundation of China(50474086)the program for New Century Talents in University(NECT)the Ministry of Education,China.
文摘In the present paper, a numerical modeling was developed to simulate the growth kinetics of ferrite transformed from austenite in Fe-C-∑X (X denotes substitution elements, such as Mn, Ni, Cr etc.) steels by solving the diffusion equation using finite difference method (FDM). Coupled with the kinetic modeling, thermodynamic calculations were carried out to determine the γ/α phase equilibrium conditions using a para-equilibrium (PE) model. The dissipation of free energy for γ→α phase transformation due to the so-called solute drag effect (SDE) was taken into account in the thermodynamic modeling. With this modeling, simulations on the growth kinetics of ferrite in the steels containing austenite-stabilizing and ferrite-stabilizing elements (such as Ni, Mn and Si, Cr, respectively) were performed, which indicates that it deviates from the parabolic growth rate law after the initial stage of transformation. The results were compared with the experimental values given by Bradley and Aaronson, showing that this model has a reasonably good accuracy to predict the growth kinetics of ferrite.
基金support from the Kazan, Mc Clain, Abrams, Fernandez, Lyons, Greenwood, Harley & Oberman Foundation, Incthe Estate of Robert Griffiths+3 种基金the Jeffrey and Karen Peterson Family FoundationPaul and Michelle Zygielbaumthe Estate of Norman Mancinithe Barbara Isackson Lung Cancer Research Fund
文摘Background and objective Maintenance of genomic integrity is essential to ensure normal organismal development and to prevent diseases such as cancer.PR-Set7(also known as Set8)is a cell cycle regulated enzyme that catalyses monomethylation of histone 4 at Lys20(H4K20me1)to promote chromosome condensation and prevent DNA damage.Recent studies show that CRL4CDT2-mediated ubiquitylation of PR-Set7 leads to its degradation during S phase and after DNA damage.This might occur to ensure appropriate changes in chromosome structure during the cell cycle or to preserve genome integrity after DNA damage.Methods We developed a new model of lung tumor development in mice harboring a conditionally expressed allele of Cul4A.We have therefore used a mouse model to demonstrate for the first time that Cul4A is oncogenic in vivo.With this model,staining of PR-Set7 in the preneoplastic and tumor lesions in Adeno Cre-induced mouse lungs was performed.Meanwhile we identified higher protein level changes ofγ-tubulin and pericentrin by IHC.Results The level of PR-Set7 down-regulated in the preneoplastic and adenocarcinomous lesions following over-expression of Cul4A.We also identified higher levels of the proteins pericentrin andγ-tubulin in Cul4A mouse lungs induced by Adeno Cre.Conclusion PR-Set7 is a direct target of Cul4A for degradation and involved in the formation of lung tumors in the conditional Cul4A transgenic mouse model.
文摘A calculation formula of ln γ i 0 for solute element i in liquid alloys was derived by use of free volume theory and Miedema formation enthalpy model. The values of ln γ i 0 of solute elements in liquid copper at 1273 K were obtained. The results obtained show that the coincidence rate of sign (positive or negative) was 90% for the calculated and experimental values, which were basically in the same magnitude.
文摘AIM To establish a rat model of anxiety-like gastric hyper-sensitivity(GHS) of functional dyspepsia(FD) induced by novel sequential stress.METHODS Animal pups were divided into two groups from postnatal day 2: controls and the sequential-stress-treated. The sequential-stress-treated group received maternal separation and acute gastric irritation early in life and restraint stress in adulthood; controls were reared undisturbed with their mothers. Rats in both groups were followed to adulthood(8 wk) at which point the anxietylike behaviors and visceromotor responses to gastric distention(20-100 mm Hg) and gastric emptying were tested. Meanwhile, alterations in several anxiety-related brain-stomach modulators including 5-hydroxytryptamine(5-HT), γ-aminobutyric acid(GABA), brain-derived neurotrophic factor(BDNF) and nesfatin-1 in the rat hippocampus, plasma and gastric fundus and the 5-HT1 A receptor(5-HT1 AR) in the hippocampal CA1 subfield and the mucosa of the gastric fundus were examined.RESULTS Sequential-stress-treated rats simultaneously demonstrated anxiety-like behaviors and GHS in dose-dependent manner compared with the control group. Although rats in both groups consumed similar amount of solid food, the rate of gastric emptying was lower in the sequentialstress-treated rats than in the control group. Sequential stress significantly decreased the levels of 5-HT(51.91 ± 1.88 vs 104.21 ± 2.88, P < 0.01), GABA(2.38 ± 0.16 vs 5.01 ± 0.13, P < 0.01) and BDNF(304.40 ± 10.16 vs 698.17 ± 27.91, P < 0.01) in the hippocampus but increased the content of nesfatin-1(1961.38 ± 56.89 vs 1007.50 ± 33.05, P < 0.01) in the same site; significantly decreased the levels of 5-HT(47.82 ± 2.29 vs 89.45 ± 2.61, P < 0.01) and BDNF(257.05 ± 12.89 vs 536.71 ± 20.73, P < 0.01) in the plasma but increased the content of nesfatin-1 in it(1391.75 ± 42.77 vs 737.88 ± 33.15, P < 0.01); significantly decreased the levels of 5-HT(41.15 ± 1.81 vs 89.17 ± 2.31, P < 0.01) and BDNF(226.49 ± 12.10 vs 551.36 ± 16.47, P < 0.01) in the gastric fundus but increased the content of nesfatin-1 in the same site(1534.75 ± 38.52 vs 819.63 ± 38.04, P < 0.01). The expressions of 5-HT1 AR in the hippocampal CA1 subfield and the mucosa of the gastric fundus were down-regulated measured by IHC(Optical Density value: Hippocampus 15253.50 ± 760.35 vs 21149.75 ± 834.13; gastric fundus 15865.25 ± 521.24 vs 23865.75 ± 1868.60; P < 0.05, respectively) and WB(0.38 ± 0.01 vs 0.57 ± 0.03, P < 0.01)(n = 8 in each group). CONCLUSION Sequential stress could induce a potential rat model of anxiety-like GHS of FD, which could be used to research the mechanisms of this intractable disease.
文摘Simulation code for a model of the adaptive immune response seen in flavivirus infections is used to explain the immunopathological consequences seen in West Nile Virus virus (WNV) infections. We use a model that specifically handles the differences in how the virus infects resting cells, the G0 state, versus dividing cells, the G1 state, which includes vastly increased MHC-I upregulation for resting cells over dividing cells. The simulation suggests how the infection progresses in a one host model and the results shed insight into the unusual survival curve data obtained for this infection: there is an increase in health even though viral load has increased.