时标上具非正中立项的二阶动力方程的动力学性质

研究时标T上的一类具非正中立项的非线性非自治二阶动力方程的动力学性质.利用时标上的有关理论,并结合一些经典不等式,得到了该方程的一些新的动力学性质,进一步推广和完善了动力方程的动力学性质.     

Electrophilic substitutions and HOMOs in azines and purines

The low reactivity of pyridine, pyridazine, pyrazine, pyrimidine, and purine toward electrophilic substitution reactions can be explained assuming a frontier orbitals control of the reaction. DFT study of the molecular orbitals of these molecules shows that the HOMOs of these substrates are not π orbitals. Furthermore, the change in the reactivity observed in pyridine-N-oxide, in activated pyrimidines, and in activated purines can be explained considering that, in this case, the HOMOs are π orbitals.     

Integrable Quasilinear Equations

We develop a classification scheme for integrable third-order scalar evolution equations using the symmetry approach to integrability. We use this scheme to study quasilinear equations of a particular type and prove that several equations that were suspected to be integrable can be reduced to the well-known Korteweg–de Vries and Krichever–Novikov equations via a Miura-type differential substitution.     

In silico prediction of deleterious single amino acid polymorphisms from amino acid sequence

Molecular cause of human disease retains as one of the most attractive scientific research targets for decades. An effective approach toward this topic is analysis and identification of disease-related amino acid polymorphisms. In this work, we developed a concise and promising deleterious amino acid polymorphism identification method SeqSubPred based on 44 features solely extracted from protein sequence. SeqSubPred achieved surprisingly good predictive ability with accuracy (0.88) and area under receiver operating characteristic (0.94) without resorting to homology or evolution information, which is frequently used in similar methods and usually more complex and time-consuming. SeqSubPred also identified several critical sequence features obtained from random forests model, and these features brought some interesting insights into the factors affecting human disease-related amino acid substitutions. The online version of SeqSubPred method is available at montana.informatics.indiana.edu/cgi-bin/seqmut/seqsubpred.cgi     

A family of integrable evolution equations of third order

We construct a family of integrable equations of the form v_t = f(v; v_x; v_xx; v_xxx) such that f is a transcendental function in v; v_x; v_xx. This family is related to the Krichever-Novikov equation by a differential substitution. Our construction of integrable equations and the corresponding differential substitutions involves geometry of a family of genus two curves and their Jacobians.     

Facile meso Functionalization of Porphyrins by Nucleophilic Substitution with Organolithium Reagents

The ruffle of the porphyrin increases with the number of meso substituents. (Octaethylporphyrin)nickel(II ) undergoes nucleophilic substitution reactions upon treatment with alkylating reagents such as butyllithium, hydrolysis with water, and oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone [DDQ; Eq. (a)]. Alkylation can be achieved at all four meso positions, and access is provided to new nonplanar porphyrins and asymmetrically substituted systems.