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71.
The systematics of the giant dipole resonance have been calculated in the open-shell RPA for all the self-conjugate sd-shell nuclei, using (i) a phenomenological Rosenfeld interaction, (ii) Barret, Hewitt and McCarthy G-matrix elements and (iii) Kuo G-matrix elements. The excitations are based on shell model ground states for all nuclei except 28Si for which a projected Hartree-Fock ground state was used. 相似文献
72.
Karr AF Feng J Lin X Sanil AP Young SS Reiter JP 《Journal of computer-aided molecular design》2005,19(9-10):739-747
We present a method for performing statistically valid linear regressions on the union of distributed chemical databases that preserves confidentiality of those databases. The method employs secure multi-party computation to share local sufficient statistics necessary to compute least squares estimators of regression coefficients, error variances and other quantities of interest. We illustrate our method with an example containing four companies' rather different databases. 相似文献
73.
74.
It is suggested that a single determinantal state in the neighbourhood of the Hartree-Fock state, having the minimum energy variance might be a ‘better’ intrinsic state for describing some of the low energy states of a nucleus. At higher excitation energies the resulting orbitals may provide a suitable single-particle basis for describing the nuclear level density at that energy. 相似文献
75.
76.
Three-dimensional quantitative structure–activity relationship (3D-QSAR) models were developed based on comparative molecular
field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA), on a series of 43 hydroxyethylamine
derivatives, acting as potent inhibitors of β-site amyloid precursor protein (APP) cleavage enzyme (BACE-1). The crystal structure of the BACE-1 enzyme (PDB ID: 2HM1)
with one of the most active compound 28 was available, and we assumed it to be the bioactive conformation of the studied series, for 3D-QSAR analysis. Statistically
significant 3D-QSAR model was established on a training set of 34 compounds, which were validated by a test set of 9 compounds.
For the best CoMFA model, the statistics are, r
2 = 0.998, r2cv = 0.810{r^{2}_{\rm cv} = 0.810} , n = 34 for the training set and r2pred = 0.934{r^{2}_{\rm pred} = 0.934} , n = 9 for the test set. For the best CoMSIA model (combined steric, electrostatic, hydrophobic, and hydrogen bond donor fields),
the statistics are r
2 = 0.978, r2cv = 0.754{r^{2}_{\rm cv} = 0.754} , n = 34 for the training set and r2pred = 0.750{r^{2}_{\rm pred} = 0.750} , n = 9 for the test set. The resulting contour maps, produced by the best CoMFA and CoMSIA models, were used to identify the
structural features relevant to the biological activity in this series of analogs. The data generated from the present study
will further help to design novel, potent, and selective BACE-1 inhibitors. 相似文献
77.
78.
The commutativity degree of a finite group is the probability that two arbitrarily chosen group elements commute. This notion has been generalized in a number of ways. The object of this article is to study yet another generalization of the same notion, which further extends some of the existing generalizations. 相似文献
79.
A facile one-pot synthesis of N-fused 1,2,4-triazoles from heterocyclic hydrazines and aldehydes is reported. The reaction is efficiently promoted by chromium (VI) oxide to afford the desired products mostly in high yields and in relatively short time. The high yield of the products and short reaction time are notable advantages of the developed protocol. This protocol is effective toward various substrates having different functionalities. 相似文献
80.
A facile one-pot synthesis of 3,5-diarylisoxazoles from α,β-unsaturated ketones and hydroxylamine hydrochloride is reported. The reaction is efficiently promoted by catalytic CuBr2 and Oxone to afford the desired products mostly in high yields and in relatively short time. The mild nature of the synthesis and short reaction time are notable advantages of the developed protocol. This protocol is effective toward various substrates having different functionalities. 相似文献