scholarly journals Aquaporin water channels in exocrine glands

2000 ◽  
Vol 15 (Suppl) ◽  
pp. S7 ◽  
Author(s):  
Martin Steward ◽  
Tae Hwan Kwon
Author(s):  
Dwight K. Romanovicz ◽  
Jacob S. Hanker

The presence of catalase-positive rods (Fig. 1) of different dimensions, which frequently have a crystalline appearance by light microscopy, has been reported. They seem to be related to peroxisomes which were characterized morphologically and cytochemically in parotid and other exocrine glands of the rat by Hand in 1973. Our light microscopic studies of these spherical microbodies and rods of different sizes, stained by virtue of the peroxidatic activity of their catalase, indicate that they are almost entirely confined to the cells of the striated and execretory ducts of the submandibular gland in the mouse. The rods were usually noted only in the proximity of the ductal microbodies. The latter frequently showed a tendency to appear in linear close array, or even to be contiguous (Fig. 2). This suggested that the rods could be formed by the fusion of microbodies.


1987 ◽  
Vol 33 (114) ◽  
pp. 239-242
Author(s):  
M. E. R. Walford

AbstractWe discuss the suggestion that small underwater transmitters might be used to illuminate the interior of major englacial water channels with radio waves. Once launched, the radio waves would naturally tend to be guided along the channels until attenuated by absorption and by radiative loss. Receivers placed within the channels or at the glacier surface could be used to detect the signals. They would provide valuable information about the connectivity of the water system. The electrical conductivity of the water is of crucial importance. A surface stream on Storglaciären, in Sweden, was found, using a low-frequency technique, to have a conductivity of approximately 4 × 10−4 S m−1. Although this is several hundred times higher than the conductivity of the surrounding glacier ice, the contrast is not sufficient to permit us simply to use electrical conductivity measurements to establish the connectivity of englacial water channels. However, the water conductivity is sufficiently small that, under favourable circumstances, radio signals should be detectable after travelling as much as a few hundred metres along an englacial water channel. In a preliminary field experiment, we demonstrated semi quantitatively that radio waves do indeed propagate as expected, at least in surface streams. We conclude that under-water radio transmitters could be of real practical value in the study of the englacial water system, provided that sufficiently robust devices can be constructed. In a subglacial channel, however, we expect the radio range would be much smaller, the environment much harsher, and the technique of less practical value.


Author(s):  
Arundhati Roy ◽  
Jie Shen ◽  
Himanshu Joshi ◽  
Woochul Song ◽  
Yu-Ming Tu ◽  
...  

1996 ◽  
Vol 16 (3) ◽  
pp. 255-259 ◽  
Author(s):  
Marja M. Ho-Dac-Pannekeet ◽  
Raymond T. Krediet
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document