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Search Results: 1 - 10 of 11378 matches for " Zhisong Cao "
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Sulfuric Acid Catalyzed Preparation of Alkyl and Alkenyl Camptothecin Ester Derivatives and Antitumor Activity against Human Xenografts Grown in Nude Mice  [PDF]
Zhisong Cao, Anthony Kozielski, Dana Vardeman, Beppino Giovanella
Open Journal of Medicinal Chemistry (OJMC) , 2012, DOI: 10.4236/ojmc.2012.21002
Abstract: Camptothecin-20-propinate (CZ48) and other camptothecin ester derivatives were prepared by the esterification reac-tions of camptothecin or 9-nitrocamptothecin with the corresponding acylating agents such as organic acid anhydride or chloride with concentrate sulfuric acid as the catalyst. The sulfuric acid-catalyzed reactions gave high yields of camptothecin ester products.Among the 11 compounds prepared by this method, camptothecin-20-O-propionate, camptothecin-20-O-crotonate, and 9-nitrocamptothecin-20-O-propionate showed good anticancer activity against various types of human tumors grown as xenografts in nude mice. The methodology developed for the preparation of camptothecin esters in this article can be applied to a wide scope of other ester derivatives.
Metabolic Difference of CZ48 in Human and Mouse Liver Microsomes
Xing Liu,Albert DeJesus,Zhisong Cao,Dana Vardeman,Beppino Giovanella
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms13055498
Abstract: CZ48, chemically camptothecin-20- O-propionate hydrate, is currently under clinical investigation. The kinetics of the metabolite camptothecin (CPT) formation and of CZ48 depletion in mouse and human liver microsomes in the presence or absence of NADPH was examined. The formation rate of camptothecin in human liver microsomes was significantly higher than that in mouse with mean K ms of 1.9 and 0.5 nM and V maxs of 9.3 and 2.2 pmol/min/mg, respectively. However, the apparent intrinsic clearance ( V max/ K m) ratios for camptothecin in human and mouse liver microsomes were not significantly different from each other (4.9 versus 4.4) in the presence of NADPH. The depletion of CZ48 in human microsomes was four times faster with 4.55% of CZ48 remaining intact while in mouse 19.11% of the drug remained unchanged after 60 min. These results suggest that there is a remarkable species difference of CZ48 biotransformation between human and mouse. The depletion rate of CZ48 in human liver microsomes is considerably higher than that in the mouse.
NO adsorption study on the distribution of Ni2 + ions on the various micro-environments of carriers
Guoxing Niu,Yao Huang,Zhisong Cao,Yufang Huang,Quanzhi Li
Chinese Science Bulletin , 1999, DOI: 10.1007/BF02887120
Abstract: The decrease of the electron density in the d orbits of Ni2 + ions, resulting from the disturbance of micro-environments in which Ni2+ ions are located, makes the frequency of adsorbed NO shlft higher. The shift degree is determined mainly by the property of the microenvironments. When Ni2+ ions are located onSII,SII(SI) sites of Y zeolite or on the surface of γ-alumina, their NO adsorption gives rise to IR bands at 1 905, 1 900 and 1 855–1 875 cm 1, respectively. The distribution of Ni2+ ions on the various micro-environments of USY zeolite, Al2O3 and MS mixed carrier has also been discussed according to the different frequencies of adsorbed NO, as well as the influence of NiO loading.
A complexity analysis of the elementary cellular automaton of rule 122
Zhisong Jiang
Chinese Science Bulletin , 2001, DOI: 10.1007/BF02900420
Abstract: S. Wolfram initiated the use of formal languages and automata theory in study of cellular automata (CAs). By means of extensive experiments with computer, he classified all CAs into four classes and conjectured that the limit languages of the third class of CAs, which produce chaotic aperiodic behavior, are not regular. Using symbolic dynamics and formal languages, we prove that the limit language of the elementary CA of rule 122 is neither regular nor context-free.
Synergic mechanism and fabrication target for bipedal nanomotors
Zhisong Wang
Physics , 2009, DOI: 10.1073/pnas.0703639104
Abstract: Inspired by dimeric motor proteins capable of undergoing transportation in living cells, significant efforts have been expended to the fabrication of track-walking nanomotors possessing two foot-like components that each can bind or detach from an array of anchorage groups on the track in response to local events of reagent consumption. The central problem in fabricating bipedal nanomotors is how the motor as a whole can gain the synergic capacity of directional track-walking, given the fact that each pedal component alone often is incapable of any directional drift. Implemented bipedal motors to date solve this thermodynamically intricate problem by an intuitive strategy that requires a hetero-pedal motor, multiple anchorage species for the track, and multiple reagent species for motor operation. Here we presented a detailed molecular mechanism by which motor-level directionality arises from a homo-pedal motor along a minimally heterogeneous track. Optimally, the operation may be reduced to a random supply of a single species of reagents to allow the motor's autonomous functioning. The mechanism suggests a distinct class of fabrication targets of drastically reduced system requirements. Intriguingly, a defective form of the mechanism falls into the realm of the well known Brownian motor mechanism, yet distinct features emerge from the normal working of the mechanism.
An Improved Kriging Interpolation Technique Based on SVM and Its Recovery Experiment in Oceanic Missing Data  [PDF]
Zhisong Huang, Huizan Wang, Ren Zhang
American Journal of Computational Mathematics (AJCM) , 2012, DOI: 10.4236/ajcm.2012.21007
Abstract: In Kriging interpolation, the types of variogram model are very finite, which make the variogram very difficult to describe the spatial distributional characteristics of true data. In order to overcome its shortage, an improved interpolation called Support Vector Machine-Kriging interpolation (SVM-Kriging) was proposed in this paper. The SVM-Kriging uses Least Square Support Vector Machine (LS-SVM) to fit the variogram, which needn’t select the basic variogram model and can directly get the optimal variogram of real interpolated field by using SVM to fit the variogram curve automatically. Based on GODAS data, by using the proposed SVM-Kriging and the general Kriging based on other traditional variogram models, the interpolation test was carried out and the interpolated results were analyzed contrastively. The test show that the variogram of SVM-Kriging can avoid the subjectivity of selecting the type of variogram models and the SVM-Kriging is better than the general Kriging based on other variogram model as a whole. Therefore, the SVM-Kriging is a good and adaptive interpolation method.
-fuzzy multiply positive implicative BCC-ideals of BCC-algebras
Jianming Zhan,Zhisong Tan
International Journal of Mathematics and Mathematical Sciences , 2003, DOI: 10.1155/s0161171203210358
Abstract: The concept of fuzzy multiply positive BCC-ideals of BCC-algebras is introduced, and then some related results are obtained. Moreover, we introduce the concept of T-fuzzy multiply positive implicative BCC-ideals of BCC-algebras and investigate T-product of T-fuzzy multiply positive implicative BCC-ideals of BCC-algebras, examining its properties. Using a t-norm T, the direct product and T-product of T-fuzzy multiply positive implicative BCC-ideals of BCC-algebras are discussed and their properties are investigated.
Doubt fuzzy BCI-algebras
Zhan Jianming,Tan Zhisong
International Journal of Mathematics and Mathematical Sciences , 2002, DOI: 10.1155/s0161171202007986
Abstract: The aim of this note is to introduce the notion of doubt fuzzy p-ideals in BCI-algebras and to study their properties. We also solve the problem of classifying doubt fuzzy p-ideals and study fuzzy relations on BCI-algebras.
Outsourcing Decision Model of Sewage Treatment Based on Emissions Trading
Zhongquan CHEN,Zhisong CHEN
International Business and Management , 2011, DOI: 10.3968/j.ibm.1923842820110301.1z0748
Abstract: This paper considers the professional treatment manufacturers to participate in emissions trading under the condition of the emissions trading which establish the supply chain between the manufacturers and the providers of professional sewage treatment. By using the strategy analysis method, under the certain conditions this study analyze the difference of the outsourcing decisions on the treatment price fluctuating. This study also conclude that the expected return of the supply chain on the strategy of all manufacturers choose to outsourcing the sewage treatment is less than the expected return on the integration supply chain strategy. Also, this research documents the existence of the supply chain. The conclusions of this paper contribute to the establishment of emissions trading under the conditions of wastewater treatment supply chain and future contributing to the sewage treatment industry with the application. Key words: Emission trading; Outsourcing decision; Sewage treatment
Role of directional fidelity in multiple extreme performance of F1-ATPase motor
Ruizheng Hou,Zhisong Wang
Physics , 2013, DOI: 10.1103/PhysRevE.88.022703
Abstract: Quantitative understanding of the best possible performance of nanomotors allowed by physical laws pertains to study of nanomotors from biology as well as nanotechnology. Biological nanomotor F1-ATPase is the best available model system as it is the only nanomotor known for extreme energy conversion near the limit of energy conservation. Using a unified theoretical framework centred on a concept called directional fidelity, we analyze recent experiments in which F1-motor's performance was measured for controlled chemical potentials, and expose from the experiments quantitative evidence for the motor's multiple extreme performance in directional fidelity, speed and catalytic capability close to physical limits. Specifically, the motor nearly exhausts available energy from the fuel to retain the highest possible directional fidelity for arbitrary load, encompassing the motor's extreme energy conversion and beyond. The theory-experiment comparison implies a tight chemomechanical coupling up to stalemate as futile steps occur but unlikely involve fuel consumption. The F1-motor data also helps clarify relation between directional fidelity and experimentally measured stepping ratio.
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