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In this paper, we investigate the linear and nonlinear photoabsorption processes in the conduction-band-confined levels of a singly charged ZnO quantum dot (QD) surrounded by HfO2 and AlN matrices. We also investigate the photoelectric process in which the conduction band electron ejects from the dot to the vacuum. We use the effective mass approximation with a finite barrier height at the dot-matrix interface. We consider the self-energy of the electron in the dot and the local field effect. The electromagnetic interaction of the incident radiation with the electron in the dot is considered in the electric dipole plus quadrupole approximation. Results for the photoabsorption coefficient and the photoelectric process are presented for different dot sizes and different intensities of incident radiation. It is found that the inclusion of the quadrupole effect reveals new photoabsorption peaks in the absorption spectra. Both the photoabsorption and photoelectric processes significantly depend on the dot size and the surrounding matrix. The change in the intensity of the incident radiation significantly influences the nonlinear photoabsorption. The photoabsorption coefficient and the photoelectric cross sections are found to be relatively higher for the ZnO QD embedded in the high-dielectric constant matrix HfO2 as compared with the lower-dielectric constant AlN matrix. [ABSTRACT FROM PUBLISHER]

Analgesic activity (log IC) of a large series of 97 analgesics was modelled topologically using a series of distance-based topological indices. The results show that analgesic activity (log IC) exhibit inter familial correlation and these can only be modelled by splitting 97 analgesics into five different categories. The regression analyses of the data show that the Wiener (W)-, Branching (B)- and first-order connectivity (χ)- indices are the better topological indices for modelling the activity (log IC), and that W index gave the excellent results. [Copyright &y& Elsevier]

The present study was undertaken to investigate if the suppressed cell-mediated immune responses observed in dengue type 2 virus (DV)- infected mice could be due to the cytotoxic factor (CF) produced in the spleens of DY-infected mice. We have observed that CF given intravenously (i.v.) kills splenic cells and reduces the total cells in the spleen. Mice treated with CF have a significantly depressed immune response to sheep erythrocytes, viz, delayed- type-hypersensitivity as measured by footpad swelling reaction at 24 hr; Jerne's antibody plaque-forming cells in the spleen; and migration inhibition of spleen cells in presence of antigen. These findings are similar to those seen earlier in DV-infected mice. [ABSTRACT FROM AUTHOR]

The records of 274 diabetics attending an outpatient clinic in New Delhi have been reviewed and the patients classified into four main types. The relationship of the disease to nutritional, socio-economic and environmental factors has been discussed. The incidence of complications in the various types is reported and the differences between them analysed. [ABSTRACT FROM PUBLISHER]