On the basis of vapor pressures, volumes of saturated vapor and liquid, both parameters "a" and "b" in Soave equation of state are treated as temperature dependent and an extended Soave equation is...On the basis of vapor pressures, volumes of saturated vapor and liquid, both parameters "a" and "b" in Soave equation of state are treated as temperature dependent and an extended Soave equation is proposed in this work. The VLE for 38 pure components including polar substances have been calculated. The comparison of calculated results with experimental data shows the prediction of liquid density is improved over Soave equation without losing the accuracy of prediction in vapor pressure and vapor density.展开更多
White layers in hard turned surfaces were identified and measured as a function ot turning parameters based on the Taguchi method. It reveals that white layers generate on the machine surface in the absence of tool fl...White layers in hard turned surfaces were identified and measured as a function ot turning parameters based on the Taguchi method. It reveals that white layers generate on the machine surface in the absence of tool flank wear, and white layer depth varies with the different combinations of hard turning parameters. Turning speed has the most important impact on white layer depth, feed rate follows, and cutting depth at last. The white layer generation consequently suggests a strong couple relation to the heat generation and thermal process of hard turning operation. White layer disappears under an optimal combination of turning parameters by Taguchi method. It suggests that a superior surface integrity without white layer is feasible under some selected combinations of turning parameters by a sharp CBN cutting tool.展开更多
The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the world.According to the basics,breadth and the i...The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the world.According to the basics,breadth and the influence,25 of the issues which considered to be the most important were screened,including"How many people can the Earth carry?"(Stokstad,2005;Dailyg et al.,1992;Cohen,1995)and"How high will the greenhouse effect make the earth temperature?展开更多
Dear Editor, Recently, engineered endonucleases, such as Zinc-Finger Nucleases （ZFNs） （Carroll, 2011）, Transcription Activator-Like Effector Nucleases （TALENs） （Mahfouz et al., 2011; Li et al., 2012）, and Clu...Dear Editor, Recently, engineered endonucleases, such as Zinc-Finger Nucleases （ZFNs） （Carroll, 2011）, Transcription Activator-Like Effector Nucleases （TALENs） （Mahfouz et al., 2011; Li et al., 2012）, and Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）-associated （Cas） systems （Cong et al., 2013） have been successfully used for gene editing in a variety of species. These systems generate double-strand breaks （DSBs） at target loci to drive site-specific DNA sequence modifica- tions. The modifications include sequence insertion and deletion and other mutations in the host genomes via the error-prone non-homologous end joining （NHEJ） pathway or sequence correction or replacement through the error-free homologous recombination （HR） pathway （Symington and Gautier, 2011）. Here, we show that the CRISPR-Cas system can be applied to generate targeted gene mutations and gene corrections in plants, and the system can also be readily engi- neered to achieve deletion of large DNA fragments and for multiplex gene editing in plants.展开更多
We use a combination of both algebraic and numerical techniques to construct a C-1-continuous, piecewise (m, n) rational epsilon-approximation of a real algebraic plane curve of degree d. At singular points we use the...We use a combination of both algebraic and numerical techniques to construct a C-1-continuous, piecewise (m, n) rational epsilon-approximation of a real algebraic plane curve of degree d. At singular points we use the classical Weierstrass Preparation Theorem and Newton power series factorizations, based on the technique of Hensel lifting. These, together with modified rational Pade approximations, are used to efficiently construct locally approximate, rational parametric representations for all real branches of an algebraic plane curve. Besides singular points we obtain an adaptive selection of simple points about which the curve approximations yield a small number of pieces yet achieve C-1 continuity between pieces. The simpler cases of C-1 and C-0 continuity are also handled in a similar manner. The computation of singularity, the approximation error bounds and details of the implementation of these algorithms are also provided.展开更多
Background Abnormal insulin secretion of pancreatic beta cells is now regarded as the more primary defect than the insulin function in the etiology of type 2 diabetes.Previous studies found impaired mitochondrial func...Background Abnormal insulin secretion of pancreatic beta cells is now regarded as the more primary defect than the insulin function in the etiology of type 2 diabetes.Previous studies found impaired mitochondrial function and impaired Ca2＋ influx in beta cells in diabetic patients and animal models,suggesting a role for these processes in proper insulin secretion.The aim of this study was to investigate the detailed relationship of mitochondrial function,Ca2＋ influx,and defective insulin secretion.Methods We investigated mitochondrial function and morphology in pancreatic beta cell of diabetic KK-Ay mice and C57BL/6J mice.Two types of Ca2＋ channel activities,L-type and store-operated Ca2＋ （SOC）,were evaluated using whole-cell patch-clamp recording.The glucose induced Ca2＋ influx was measured by a non-invasive micro-test technique （NMT）.Results Mitochondria in KK-Ay mice pancreatic beta cells were swollen with disordered cristae,and mitochondrial function decreased compared with C57BL/6J mice.Ca2＋ channel activity was increased and glucose induced Ca2＋ influx was impaired,but could be recovered by genipin.Conclusion Defective mitochondrial function in diabetic mice pancreatic beta cells is a key cause of abnormal insulin secretion by altering Ca2＋ influx,but not via Ca2＋ channel activity.展开更多
文摘On the basis of vapor pressures, volumes of saturated vapor and liquid, both parameters "a" and "b" in Soave equation of state are treated as temperature dependent and an extended Soave equation is proposed in this work. The VLE for 38 pure components including polar substances have been calculated. The comparison of calculated results with experimental data shows the prediction of liquid density is improved over Soave equation without losing the accuracy of prediction in vapor pressure and vapor density.
基金The Ministry of Education of China"985"of International cooperation project"Clean Manufactur-ing Technology"
文摘White layers in hard turned surfaces were identified and measured as a function ot turning parameters based on the Taguchi method. It reveals that white layers generate on the machine surface in the absence of tool flank wear, and white layer depth varies with the different combinations of hard turning parameters. Turning speed has the most important impact on white layer depth, feed rate follows, and cutting depth at last. The white layer generation consequently suggests a strong couple relation to the heat generation and thermal process of hard turning operation. White layer disappears under an optimal combination of turning parameters by Taguchi method. It suggests that a superior surface integrity without white layer is feasible under some selected combinations of turning parameters by a sharp CBN cutting tool.
基金granted by the United Nations Educational,Scientific and Cultural Organization program(IGCP665)the China basic geological Investigation Program(Grant No.DD20160316).
文摘The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the world.According to the basics,breadth and the influence,25 of the issues which considered to be the most important were screened,including"How many people can the Earth carry?"(Stokstad,2005;Dailyg et al.,1992;Cohen,1995)and"How high will the greenhouse effect make the earth temperature?
文摘Dear Editor, Recently, engineered endonucleases, such as Zinc-Finger Nucleases （ZFNs） （Carroll, 2011）, Transcription Activator-Like Effector Nucleases （TALENs） （Mahfouz et al., 2011; Li et al., 2012）, and Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）-associated （Cas） systems （Cong et al., 2013） have been successfully used for gene editing in a variety of species. These systems generate double-strand breaks （DSBs） at target loci to drive site-specific DNA sequence modifica- tions. The modifications include sequence insertion and deletion and other mutations in the host genomes via the error-prone non-homologous end joining （NHEJ） pathway or sequence correction or replacement through the error-free homologous recombination （HR） pathway （Symington and Gautier, 2011）. Here, we show that the CRISPR-Cas system can be applied to generate targeted gene mutations and gene corrections in plants, and the system can also be readily engi- neered to achieve deletion of large DNA fragments and for multiplex gene editing in plants.
文摘We use a combination of both algebraic and numerical techniques to construct a C-1-continuous, piecewise (m, n) rational epsilon-approximation of a real algebraic plane curve of degree d. At singular points we use the classical Weierstrass Preparation Theorem and Newton power series factorizations, based on the technique of Hensel lifting. These, together with modified rational Pade approximations, are used to efficiently construct locally approximate, rational parametric representations for all real branches of an algebraic plane curve. Besides singular points we obtain an adaptive selection of simple points about which the curve approximations yield a small number of pieces yet achieve C-1 continuity between pieces. The simpler cases of C-1 and C-0 continuity are also handled in a similar manner. The computation of singularity, the approximation error bounds and details of the implementation of these algorithms are also provided.
基金This study was supported by grants from Fund of Capital Medical Development and Research （No. 2009-1020） and Tsinghua-Yue-Yuen Medical Science Foundation （No.20240000531 and No.20240000568）
文摘Background Abnormal insulin secretion of pancreatic beta cells is now regarded as the more primary defect than the insulin function in the etiology of type 2 diabetes.Previous studies found impaired mitochondrial function and impaired Ca2＋ influx in beta cells in diabetic patients and animal models,suggesting a role for these processes in proper insulin secretion.The aim of this study was to investigate the detailed relationship of mitochondrial function,Ca2＋ influx,and defective insulin secretion.Methods We investigated mitochondrial function and morphology in pancreatic beta cell of diabetic KK-Ay mice and C57BL/6J mice.Two types of Ca2＋ channel activities,L-type and store-operated Ca2＋ （SOC）,were evaluated using whole-cell patch-clamp recording.The glucose induced Ca2＋ influx was measured by a non-invasive micro-test technique （NMT）.Results Mitochondria in KK-Ay mice pancreatic beta cells were swollen with disordered cristae,and mitochondrial function decreased compared with C57BL/6J mice.Ca2＋ channel activity was increased and glucose induced Ca2＋ influx was impaired,but could be recovered by genipin.Conclusion Defective mitochondrial function in diabetic mice pancreatic beta cells is a key cause of abnormal insulin secretion by altering Ca2＋ influx,but not via Ca2＋ channel activity.
