We introduce generalized excellent extension of ring R in [4]. If S is a generalized excellent extension of R, we prove that (1) wgldim S≤ wgldim R and glodim S≤ gldim R; (2) the relations between rings R and rings S.
2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory （DFT） method at B3LYP/6-31G （d） level. The structure of syn-2,4-di-p-tolylpentane-2,4...2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory （DFT） method at B3LYP/6-31G （d） level. The structure of syn-2,4-di-p-tolylpentane-2,4-diol （2b） was characterized by X-ray diffraction and compared with the crystal structures of anti- and syn-2,4-diphenylpentane-2,4-diols （la and lb）. X-ray diffraction indicates that inter and intra-molecular hydrogen bonds are formed in the crystal structures. There is n-n staking interaction in lb and 2b. Good linear correlations and similar results are found between the experimental 1H and 13C NMR chemical shifts （6~exp） and GIAO （Gauge Independent Atomic Orbital） method calculated magnetic isotropic shielding tensors （acalc）. HOMO and LUMO molecular orbitals were calculated at the same levels with the different results. UV-vis absorption spectra of the compounds were recorded in EtOH, MeCN, n-BuOH and cyclohexane with different dielectric constants. It is found that the solvent effect is obvious when e is 24.85（EtOH）, 35.69（MeCN） and it is weak when e is decreased to 17.33（n-BuOH）, 1.18 （cyclohexane）.展开更多
Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 ...Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 weeks. After blood glucose met the criteria of diabetes(over 16.7 mmol/L), mice were randomly divided into 3 groups: a control group(without any treatment), a rosiglitazone group(treated with rosiglitazone 12.5 mg/kg·d once per day), and a metformin group(treated with metformin 3 g/kg·d twice daily). After 4 weeks, we then determined the expression of PTEN and phosphoserine 473-Akt(pS473-Akt) in the epididymal adipose tissue with Western blots. The mice in each group were further divided into the insulin(-) subgroup and insulin(+) subgroup, which were intraperitoneally injected with saline and insulin(5 mU/g body weight), respectively. Results The expression of PTEN was elevated in the epididymal adipose tissue obtained from KKAy diabetic mice compared with that from the C57BL/6J mice(P<0.001). In accordance with the enhanced expression of PTEN, the level of pS473-Akt stimulated by insulin was decreased in the adipose tissue of KKAy mice compared to the C57BL/6J mice(P<0.001). Treatment with the insulin-sensitizing agents, rosiglitazone and metformin did not inhibit the elevated expression of PTEN in adipose tissue of KKAy diabetic mice. Conclusion PTEN may play an important role in the development of insulin resistance in adipose tissue of type 2 diabetes mice model.展开更多
AIM: To investigate the correlation between expression of phosphatase and tensin homolog (PTEN) and cetuximab effects in colorectal cancer. METHODS: We searched PubMed, EMBASE and ASCO to identify eligible studies. Fi...AIM: To investigate the correlation between expression of phosphatase and tensin homolog (PTEN) and cetuximab effects in colorectal cancer. METHODS: We searched PubMed, EMBASE and ASCO to identify eligible studies. Finally, 8 randomized control studies were included in the meta-analysis. STATA 10.0 Software was used to investigate heterogeneity among individual studies and to summarize all the studies. Risk ratios (RRs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were used to assess the strength of the association. RESULTS: Compared with 20 of 266 patients with loss of PTEN, 206 of 496 patients with intact PTEN protein expression had a better objective response rate to cetuximab-based therapy (RR, 4.75; 95% CI, 2.59-8.72; P < 0.001). PTEN positivity was associated with better progression-free survival (PFS) (HR, 0.675; 95% CI, 0.473-0.964; P = 0.031) but not with better overall survival (OS) (HR, 0.608; 95% CI, 0.411-0.899; P = 0.013). In patients with KRAS wild-type status, PTEN positivity did not predict a longer PFS or OS (PFS: HR, 0.707; 95% CI, 0.440-1.138; P = 0.154; OS: HR, 0.943; 95% CI, 0.646-1.377; P = 0.761). CONCLUSION: Expression of PTEN is related to the effect of cetuximab in colorectal cancer patients and should be considered in treatment with cetuximab.展开更多
AIM:To investigate the impact of phosphatase and tensin homolog(Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/loxP system,a mouse with conditional intestinal epithelial ...AIM:To investigate the impact of phosphatase and tensin homolog(Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/loxP system,a mouse with conditional intestinal epithelial Pten deficiency was generated.Pten mutant mice and controls were sacrificed and small intestines collected for immunofluorescence and quantitative real-time polymerase chain reaction.Blood was collected on 16 h fasted mice by cardiac puncture.Enzyme-linked immunosorbent assay was used to measure blood circulating ghrelin,somatostatin(SST) and glucose-dependent insulinotropic peptide(GIP) levels.RESULTS:Results show an unexpected dual regulatory role for epithelial Pten signalling in the specification/differentiation of enteroendocrine cell subpopulations in the small intestine.Our data indicate that Pten positively regulates chromogranin A(CgA) expressing subpopulations,including cells expressing secretin,ghrelin,gastrin and cholecystokinin(CCK).In contrast,Pten negatively regulates the enteroendocrine subtype specification of non-expressing CgA cells such as GIP and SST expressing cells.CONCLUSION:The present results demonstrate that Pten signalling favours the enteroendocrine progenitor to specify into cells expressing CgA including those producing CCK,gastrin and ghrelin.展开更多
Using the latest reported homologous Chemokine receptors （PDB ID： 3ODU, 3OE0 and 3OE6） as templates, twenty models of angiotensin II （Ang II） type 1 （AT1） receptor （known as p30556） were generated by multiple...Using the latest reported homologous Chemokine receptors （PDB ID： 3ODU, 3OE0 and 3OE6） as templates, twenty models of angiotensin II （Ang II） type 1 （AT1） receptor （known as p30556） were generated by multiple templates homology modeling. According to the results of the initial validation of these twenty models, the model 0020 was finally chosen as the best one for further studies. Then, a 2 ns molecular dynamic （MD） simulation for model 0020 was conducted in normal saline （0.9%, w/F） under periodical boundary conditions, which was followed by docking studies of model 0020 with several existing AT1 receptor blockers （ARBs）. The docking results reveal that model 0020 possesses good affinities with these docked ARBs which are in accordance with both the IC50 inhibitor values and their curative effects. The results also show more potent interactions between the model 0020 and its ARBs than those of ever reported results, such as hydrogen bonds, hydrophobic interactions, and especially cation-n interactions and π-π interactions which have never been reported before. This may reveal that the structure of the model 0020 is quite close to its real crystal structure and the model 0020 may have the potential to be used for structure based drug design：展开更多
Let ρ be a congruence on a semingroup S.ρis called a rectangular band congruence if S/ρ is a rectangular band. In this paper the least restangular band congruence on a senigroup is disccribed . Let T be a subsemi...Let ρ be a congruence on a semingroup S.ρis called a rectangular band congruence if S/ρ is a rectangular band. In this paper the least restangular band congruence on a senigroup is disccribed . Let T be a subsemigroup of a semigroup S. A necessary and sufficient condition for which every rectangular band congruence on T can be uniquely extended to a rectangular band congruence on S is given.展开更多
This is a note on Abrams＇ paper ＂Modules, Comodules, and Cotensor Products over Frobenius Algebras, Journal of Algebras＂ （1999）. With the application of Frobenius coordinates developed recently by Kadison, one ha...This is a note on Abrams＇ paper ＂Modules, Comodules, and Cotensor Products over Frobenius Algebras, Journal of Algebras＂ （1999）. With the application of Frobenius coordinates developed recently by Kadison, one has a direct proof of Abrams＇ characterization for Frobenius algebras in terms of comultiplication （see L. Kadison （1999））. For any Frobenius algebra, by using the explicit comultiplication, the explicit correspondence between the category of modules and the category of comodules is obtained. Moreover, with this we give very simplified proofs and improve Abrams＇ results on the Hom functor description of cotensor functor.展开更多
In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extensi...In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extension algebras.展开更多
The first cohomology group of generalized loop Virasoro algebras with coefficients in the tensor product of its adjoint module is shown to be trivial. The result is used to prove that Lie bialgebra structures on gener...The first cohomology group of generalized loop Virasoro algebras with coefficients in the tensor product of its adjoint module is shown to be trivial. The result is used to prove that Lie bialgebra structures on generalized loop Virasoro algebras are coboundary triangular. The authors generalize the results to generalized map Virasoro algebras.展开更多
We argue that more cosmological solutions in massive gravity can be obtained if the metric tensor and the tensor ∑μv defined by Stiickelberg fields take the homogeneous and isotropic form. The standard cosmology wit...We argue that more cosmological solutions in massive gravity can be obtained if the metric tensor and the tensor ∑μv defined by Stiickelberg fields take the homogeneous and isotropic form. The standard cosmology with matter and radiation dominations in the past can be recovered and ACDM model is easily obtained. The dynamical evolution of the universe is modified at very early times.展开更多
We show that two module homomorphisms for groups and Lie algebras established by Xi(2012)can be generalized to the setting of quasi-triangular Hopf algebras.These module homomorphisms played a key role in his proof of...We show that two module homomorphisms for groups and Lie algebras established by Xi(2012)can be generalized to the setting of quasi-triangular Hopf algebras.These module homomorphisms played a key role in his proof of a conjecture of Yau(1998).They will also be useful in the problem of decomposition of tensor products of modules.Additionally,we give another generalization of result of Xi(2012)in terms of Chevalley-Eilenberg complex.展开更多
The finite element analysis （FEA） technology by hydraulic-mechanical-damage （HMD） coupling is proposed in this paper for wellbore stability analysis of transversely isotropic rock, developed basing on the recently...The finite element analysis （FEA） technology by hydraulic-mechanical-damage （HMD） coupling is proposed in this paper for wellbore stability analysis of transversely isotropic rock, developed basing on the recently established FEA technology for iso- tropic rock. The finite element （FE） solutions of numerical wellbore model, damage tensor calculation and Pariseau strength criterion for transversely isotropic rock are developed for researching the wellbore failure characteristics and computing the collapse and fracture pressure of laminated rock as shale reservoirs. The classic Blot constitutive for rock as porous medium is introduced to establish a set of FE equations coupling with elastic solid deformation and seepage flow. To be in accord with the inclined wellbore situation, the coordinate transformation for global, wellbore, in-situ stress and transversely isotropic for- mation coordinate systems is established for describing the in-situ stress field and the results in laminated rock. To be in accord with the practical situation, a three-dimensional FIE model is developed, in which several other auxiliary technologies are com- prehensively utilized, e.g., the typical Weibull distribution function for heterogeneous material description and adaptive tech- nology for mesh refinement. The damage tensor calculation technology for transversely isotropic rock are realized from the well-developed continuum damage variable of isotropic rock. The rock is subsequently developed into a novel conceptual and practical model considering the stress and permeability with the damage. The proposed method utilizing Parisean strength cri- terion fully reflects the strength parameters parallel or perpendicular to bedding of the transversely isotropic rock. To this end, an effective and reliable numerically three-step FEA strategy is well established. Numerical examples are given to show that the proposed method can establish efficient and applicable FE model and be suitable for analyzing the state of pore pressure and stress surrounding wellbore, furthermore to demonstrate the effectiveness and reliability of the instability analysis of wellbore failure region and the safe mud weight computation for collapse and fracture pressure of transversely isotropic rock.展开更多
We completely determine the universal central extension of the generalized orthosymplectic Lie superalgebra ospm 12n（R,-） that is coordinatized by an arbitrary unital associative superalgebra （R,-） with superinvol...We completely determine the universal central extension of the generalized orthosymplectic Lie superalgebra ospm 12n（R,-） that is coordinatized by an arbitrary unital associative superalgebra （R,-） with superinvolution. As a result, an identification between the second homology group of the Lie superalgebra ospm｜2n （R,-） and the first skew-dihedral homology group of the associative superalgebra （R,-） with superin-volution is created for positive integers m and n with （m, n）≠ （1, 1） and （m, n）≠（2, 1）. The second homology groups of the Lie superalgebras ospm1｜2（R,-） and ospm｜2n （R,-） are also characterized explicitly.展开更多
文摘We introduce generalized excellent extension of ring R in [4]. If S is a generalized excellent extension of R, we prove that (1) wgldim S≤ wgldim R and glodim S≤ gldim R; (2) the relations between rings R and rings S.
基金Projects(21072053,20772028)supported by the National Natural Science Foundation of ChinaProjects(10K025,11C0527)supported by the Scientific Research Fund of Hunan Provincial Education Department,ChinaProject(LKF0901)supported by the Open Foundation of Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education,Hunan University of Science and Technology,China
文摘2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory （DFT） method at B3LYP/6-31G （d） level. The structure of syn-2,4-di-p-tolylpentane-2,4-diol （2b） was characterized by X-ray diffraction and compared with the crystal structures of anti- and syn-2,4-diphenylpentane-2,4-diols （la and lb）. X-ray diffraction indicates that inter and intra-molecular hydrogen bonds are formed in the crystal structures. There is n-n staking interaction in lb and 2b. Good linear correlations and similar results are found between the experimental 1H and 13C NMR chemical shifts （6~exp） and GIAO （Gauge Independent Atomic Orbital） method calculated magnetic isotropic shielding tensors （acalc）. HOMO and LUMO molecular orbitals were calculated at the same levels with the different results. UV-vis absorption spectra of the compounds were recorded in EtOH, MeCN, n-BuOH and cyclohexane with different dielectric constants. It is found that the solvent effect is obvious when e is 24.85（EtOH）, 35.69（MeCN） and it is weak when e is decreased to 17.33（n-BuOH）, 1.18 （cyclohexane）.
基金Supported by National Natural Science Foundation of China(81270878)National Key Program of Clinical Science of China(WBYZ2011-873)
文摘Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 weeks. After blood glucose met the criteria of diabetes(over 16.7 mmol/L), mice were randomly divided into 3 groups: a control group(without any treatment), a rosiglitazone group(treated with rosiglitazone 12.5 mg/kg·d once per day), and a metformin group(treated with metformin 3 g/kg·d twice daily). After 4 weeks, we then determined the expression of PTEN and phosphoserine 473-Akt(pS473-Akt) in the epididymal adipose tissue with Western blots. The mice in each group were further divided into the insulin(-) subgroup and insulin(+) subgroup, which were intraperitoneally injected with saline and insulin(5 mU/g body weight), respectively. Results The expression of PTEN was elevated in the epididymal adipose tissue obtained from KKAy diabetic mice compared with that from the C57BL/6J mice(P<0.001). In accordance with the enhanced expression of PTEN, the level of pS473-Akt stimulated by insulin was decreased in the adipose tissue of KKAy mice compared to the C57BL/6J mice(P<0.001). Treatment with the insulin-sensitizing agents, rosiglitazone and metformin did not inhibit the elevated expression of PTEN in adipose tissue of KKAy diabetic mice. Conclusion PTEN may play an important role in the development of insulin resistance in adipose tissue of type 2 diabetes mice model.
文摘AIM: To investigate the correlation between expression of phosphatase and tensin homolog (PTEN) and cetuximab effects in colorectal cancer. METHODS: We searched PubMed, EMBASE and ASCO to identify eligible studies. Finally, 8 randomized control studies were included in the meta-analysis. STATA 10.0 Software was used to investigate heterogeneity among individual studies and to summarize all the studies. Risk ratios (RRs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were used to assess the strength of the association. RESULTS: Compared with 20 of 266 patients with loss of PTEN, 206 of 496 patients with intact PTEN protein expression had a better objective response rate to cetuximab-based therapy (RR, 4.75; 95% CI, 2.59-8.72; P < 0.001). PTEN positivity was associated with better progression-free survival (PFS) (HR, 0.675; 95% CI, 0.473-0.964; P = 0.031) but not with better overall survival (OS) (HR, 0.608; 95% CI, 0.411-0.899; P = 0.013). In patients with KRAS wild-type status, PTEN positivity did not predict a longer PFS or OS (PFS: HR, 0.707; 95% CI, 0.440-1.138; P = 0.154; OS: HR, 0.943; 95% CI, 0.646-1.377; P = 0.761). CONCLUSION: Expression of PTEN is related to the effect of cetuximab in colorectal cancer patients and should be considered in treatment with cetuximab.
基金Supported by The Canadian Institutes of Health Research team grant,CTP-82942 to Carrier JC,Boudreau F,Rivard N,Perreault NCarrier JC,Boudreau F and Perreault N are scholars from the Fonds de la Recherche en Santé du Québec+1 种基金Rivard N is a recipi-ent of a Canadian Research Chair in Signaling and Digestive PhysiopathologyRivard N,Perreault N,Carrier JC and Bou-dreau F are members of the FRSQ-funded "Centre de Recherche Clinique étienne Lebel"
文摘AIM:To investigate the impact of phosphatase and tensin homolog(Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/loxP system,a mouse with conditional intestinal epithelial Pten deficiency was generated.Pten mutant mice and controls were sacrificed and small intestines collected for immunofluorescence and quantitative real-time polymerase chain reaction.Blood was collected on 16 h fasted mice by cardiac puncture.Enzyme-linked immunosorbent assay was used to measure blood circulating ghrelin,somatostatin(SST) and glucose-dependent insulinotropic peptide(GIP) levels.RESULTS:Results show an unexpected dual regulatory role for epithelial Pten signalling in the specification/differentiation of enteroendocrine cell subpopulations in the small intestine.Our data indicate that Pten positively regulates chromogranin A(CgA) expressing subpopulations,including cells expressing secretin,ghrelin,gastrin and cholecystokinin(CCK).In contrast,Pten negatively regulates the enteroendocrine subtype specification of non-expressing CgA cells such as GIP and SST expressing cells.CONCLUSION:The present results demonstrate that Pten signalling favours the enteroendocrine progenitor to specify into cells expressing CgA including those producing CCK,gastrin and ghrelin.
基金Project(20876180)supported by the National Natural Science Foundation of China
文摘Using the latest reported homologous Chemokine receptors （PDB ID： 3ODU, 3OE0 and 3OE6） as templates, twenty models of angiotensin II （Ang II） type 1 （AT1） receptor （known as p30556） were generated by multiple templates homology modeling. According to the results of the initial validation of these twenty models, the model 0020 was finally chosen as the best one for further studies. Then, a 2 ns molecular dynamic （MD） simulation for model 0020 was conducted in normal saline （0.9%, w/F） under periodical boundary conditions, which was followed by docking studies of model 0020 with several existing AT1 receptor blockers （ARBs）. The docking results reveal that model 0020 possesses good affinities with these docked ARBs which are in accordance with both the IC50 inhibitor values and their curative effects. The results also show more potent interactions between the model 0020 and its ARBs than those of ever reported results, such as hydrogen bonds, hydrophobic interactions, and especially cation-n interactions and π-π interactions which have never been reported before. This may reveal that the structure of the model 0020 is quite close to its real crystal structure and the model 0020 may have the potential to be used for structure based drug design：
文摘Let ρ be a congruence on a semingroup S.ρis called a rectangular band congruence if S/ρ is a rectangular band. In this paper the least restangular band congruence on a senigroup is disccribed . Let T be a subsemigroup of a semigroup S. A necessary and sufficient condition for which every rectangular band congruence on T can be uniquely extended to a rectangular band congruence on S is given.
基金Project supported by AsiaLink Project "Algebras and Representations in China and Europe" ASI/B7-301/98/679-11 and the National Natural Science Foundation of China (No.10271113).
文摘This is a note on Abrams＇ paper ＂Modules, Comodules, and Cotensor Products over Frobenius Algebras, Journal of Algebras＂ （1999）. With the application of Frobenius coordinates developed recently by Kadison, one has a direct proof of Abrams＇ characterization for Frobenius algebras in terms of comultiplication （see L. Kadison （1999））. For any Frobenius algebra, by using the explicit comultiplication, the explicit correspondence between the category of modules and the category of comodules is obtained. Moreover, with this we give very simplified proofs and improve Abrams＇ results on the Hom functor description of cotensor functor.
基金supported by National Natural Science Foundation of China (Grant No. 10626031)Natural Science Foundation of Shandong Province (Grant No. Y2006A03)the Scientific Research Project of the Department of Education of Shandong Province (Grant No. J08LI15)
文摘In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extension algebras.
基金supported by the National Natural Science Foundation of China(Nos.10825101,11431010,11271284,11101269)the Scientific Research Starting Foundation for Doctors,Shanghai Ocean University(No.A-0209-13-0105380)the Youth Scholars of Shanghai Higher Education Institutions(No.ZZHY14026)
文摘The first cohomology group of generalized loop Virasoro algebras with coefficients in the tensor product of its adjoint module is shown to be trivial. The result is used to prove that Lie bialgebra structures on generalized loop Virasoro algebras are coboundary triangular. The authors generalize the results to generalized map Virasoro algebras.
基金Supported by the National Basic Science Program (Project 973) of China under Grant No. 2010CB833004the National Natural Science Foundation of China under Grant Nos. 10935013 and 11175270the Fundamental Research Funds for the Central Universities
文摘We argue that more cosmological solutions in massive gravity can be obtained if the metric tensor and the tensor ∑μv defined by Stiickelberg fields take the homogeneous and isotropic form. The standard cosmology with matter and radiation dominations in the past can be recovered and ACDM model is easily obtained. The dynamical evolution of the universe is modified at very early times.
基金supported by National Natural Science Foundation of China (Grant No. 11501546)
文摘We show that two module homomorphisms for groups and Lie algebras established by Xi(2012)can be generalized to the setting of quasi-triangular Hopf algebras.These module homomorphisms played a key role in his proof of a conjecture of Yau(1998).They will also be useful in the problem of decomposition of tensor products of modules.Additionally,we give another generalization of result of Xi(2012)in terms of Chevalley-Eilenberg complex.
基金supported by the National Natural Science Foundation of China(Grant Nos.11372157&11302115)the Doctoral Fund of Ministry of Education of China(Grant No.20120002110075)+1 种基金the Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No.201326)the China Postdoctoral Science Foundation(Grant No.2015M571030)
文摘The finite element analysis （FEA） technology by hydraulic-mechanical-damage （HMD） coupling is proposed in this paper for wellbore stability analysis of transversely isotropic rock, developed basing on the recently established FEA technology for iso- tropic rock. The finite element （FE） solutions of numerical wellbore model, damage tensor calculation and Pariseau strength criterion for transversely isotropic rock are developed for researching the wellbore failure characteristics and computing the collapse and fracture pressure of laminated rock as shale reservoirs. The classic Blot constitutive for rock as porous medium is introduced to establish a set of FE equations coupling with elastic solid deformation and seepage flow. To be in accord with the inclined wellbore situation, the coordinate transformation for global, wellbore, in-situ stress and transversely isotropic for- mation coordinate systems is established for describing the in-situ stress field and the results in laminated rock. To be in accord with the practical situation, a three-dimensional FIE model is developed, in which several other auxiliary technologies are com- prehensively utilized, e.g., the typical Weibull distribution function for heterogeneous material description and adaptive tech- nology for mesh refinement. The damage tensor calculation technology for transversely isotropic rock are realized from the well-developed continuum damage variable of isotropic rock. The rock is subsequently developed into a novel conceptual and practical model considering the stress and permeability with the damage. The proposed method utilizing Parisean strength cri- terion fully reflects the strength parameters parallel or perpendicular to bedding of the transversely isotropic rock. To this end, an effective and reliable numerically three-step FEA strategy is well established. Numerical examples are given to show that the proposed method can establish efficient and applicable FE model and be suitable for analyzing the state of pore pressure and stress surrounding wellbore, furthermore to demonstrate the effectiveness and reliability of the instability analysis of wellbore failure region and the safe mud weight computation for collapse and fracture pressure of transversely isotropic rock.
基金supported by National Natural Science Foundation of China (Grant No. 11501213)the China Postdoctoral Science Foundation (Grant No. 2015M570705)+2 种基金the Fundamental Research Funds for the Central Universities (Grant No. 2015ZM085)the China Postdoctoral Science Foundation (Grant No. 2015M571928)the Fundamental Research Funds for the Central Universities
文摘We completely determine the universal central extension of the generalized orthosymplectic Lie superalgebra ospm 12n（R,-） that is coordinatized by an arbitrary unital associative superalgebra （R,-） with superinvolution. As a result, an identification between the second homology group of the Lie superalgebra ospm｜2n （R,-） and the first skew-dihedral homology group of the associative superalgebra （R,-） with superin-volution is created for positive integers m and n with （m, n）≠ （1, 1） and （m, n）≠（2, 1）. The second homology groups of the Lie superalgebras ospm1｜2（R,-） and ospm｜2n （R,-） are also characterized explicitly.
