the concentration of selected trace metals (fe, cd, cu, pb, and zn) in 30surface sediments were measured using atomic absorption spectrometer to investigatethe spatial and seasonal variations of trace metals along kanyakumari coast, india. toassess the environmental risk of trace metals, enrichment factor, geo-accumulation index,pollution load index, and ecological risk index have been calculat...

High spatial resolution, narrow band, infrared line images and CO (1—0) mm interferometer data are presented for NGC 7027. These data trace emission from the central H II region (Bra), the intermediate photodissociation region [H2 1—0S(1) and 3.3 /im dust feature], and the molecular circumstellar envelope [CO (1—0)]. The H II region lies in a cavity in the CO envelope, and consists of a smooth ...

We have studied the influence of far ultraviolet (UV) radiation (6 < hν < 13.6 eV) from a massive young stellar object (YSO) on the chemistry of its own envelope by extending the models of Doty et al. (2002) to include a central source of UV radiation. The models are applied to the massive star-forming region AFGL 2591 for different inner UV field strengths. Depth-dependent abundance profiles f...

We conducted wide-field JHKs imaging polarimetry toward NGC 2024, which is a massive star-forming region in the Orion B cloud. We found a prominent and extended polarized nebula over NGC 2024, and constrained the location of illuminating source of the nebula through the analysis of polarization vectors. A massive star, IRS 2b with a spectral type of O8 − B2, is located in the center of the symm...

In this paper, we consider the (upper) semigroup envelope, i.e., least upper bound, of a given family linear Feller semigroups. We explicitly construct envelope and show that, ...

Using fluorescence spectroscopy, we have demonstrated that isolated envelope membranes from mature spinach chloroplasts catalyze the phototransformation of endogenous protochlorophyllide into chlorophyllide in presence of NADPH, but not in presence of NADH. Protochlorophyllide reductase was characterized further using monospecific antibodies (anti-protochlorophyllide reductase) raised against t...

In a series of experiments we compared orientation discrimination performance for Gabor stimuli in which the stimulus profile was either matched to the receptive field profile of single V1 simple cells ('simple'), or in which the carrier and envelope orientations were different ('tigertails'). In the first Experiment, using small, high spatial frequency, peripheral stimuli to minimise the numbe...