This paper deals with the dynamic characteristics of the siphon which is usually applied to control the movement of rain water from the collecting funnel of a raingauge to the compartments of the tipping bucket. Since commercially available tipping bucket raingauges suffer from nonlinearity, a modified siphon has been tested. The dimensions of its elements have been designed to meet linearity r...

To examine the relationship between synaptic plasticity and learning and memory as directly as possible, we have developed a new simplified preparation for studying the siphon-withdrawal reflex of Aplysia in which it is relatively easy to record synaptic connections between individual identified neurons during simple forms of learning. We estimated that monosynaptic EPSPs from LE siphon sensory...

An inscription on the supporting wall of the inverted siphon of the aqueduct of the ancient Roman city of Patara, SW Turkey, explains how the wall collapsed during an earthquake and was subsequently restored. Carbonate deposits formed inside the aqueduct channel show cyclic stable isotope changes representing 17 years of deposition. This sequence, together with the text of the inscription, allo...

BACKGROUND AND PURPOSE Calcification in the coronary arteries has been correlated with significant vessel stenosis. The predictive value of calcification within the carotid siphon has not been characterized; however, stenosis in the carotid siphon is potentially important in determining management of patients with ipsilateral carotid bifurcation stenosis. The purpose of this study was to determ...

Prognosis of Carotid Siphon Stenosis To the Editor: In their interesting paper, Wechsler et al confirmed that siphon stenosis carries a poor prognosis for life, as one-third of their patients were dead at the end of a 51-month follow-up. In a previous study involving 15 patients with siphon stenosis of > 30% (without proximal atherosclerosis of equal or greater severity), we also found a high m...

Prognosis of Carotid Siphon Stenosis To the Editor: In their interesting paper, Wechsler et al confirmed that siphon stenosis carries a poor prognosis for life, as one-third of their patients were dead at the end of a 51-month follow-up. In a previous study involving 15 patients with siphon stenosis of > 30% (without proximal atherosclerosis of equal or greater severity), we also found a high m...

Here we present retrieval of Peripheral Blood Mononuclear Cells by density-gradient medium based centrifugation for subsequent analysis of the leukocytes on an integrated microfluidic "Lab-on-a-Disc" cartridge. Isolation of white blood cells constitutes a critical sample preparation step for many bioassays. Centrifugo-pneumatic siphon valves are particularly suited for blood processing as they ...

Modulation of the strength of siphon and tail withdrawal reflexes in Aplysia involves, in part, changes in the sensory neurons that initiate these reflexes. Different observations and experiments on modulation in siphon and tail sensory neurons together contribute to the working model of mechanisms of learning and memory in Aplysia, yet no direct comparison of modulation in these two classes of...