The level of postganglionic sympathetic nerve activity is
important in determining the tone of vascular smooth muscle, and
subsequent maintenance of normal blood pressure. It is generally
agreed that receptors located on postganglionic nerve terminals
(pre-junctional alpha₂ receptors) are important in the modulation of
neurotransmitter (norepinephrine) release from these nerves....
Prothoracicotropic hormone has been partially purified
from whole heads of tobacco hornworm larvae, Manduca sexta.
Activity was followed with a larval bioassay. Activity was
purified 4400 fold from crude extracts. The hormone was
found to be a heat-stable polypeptide with an approximate
molecular weight of 25,000 Daltons. The hormone has...
An analog simulation of the postural control system (PCS) of a
dog is used to illustrate how modern systems simulation can be applied
to a study of complex life systems. Even though many bold
assumptions were required to adequately simplify the PCS model, the
simulation provided intuitive insight and gave...
BACKGROUND/PURPOSE: Exposure from medical radiation sources are on the rise in the United States. Often the highest potential source of radiation dose to patients and radiology staff occur during interventional radiology procedures performed using fluoroscopy and digital subtraction angiography (DSA) to provide image guidance in minimally invasive surgical procedures. Several...
The present study characterized physiological responsivity during moral elevation, or elevation, a prosocial emotional state triggered by witnessing displays of altruism and moral beauty. Participants watched video stimuli that induced elevation, or amusement as a control condition, while heart rate (HR), respiratory sinus arrhythmia (RSA), skin conductance responses (SCR), and...
Circadian clocks are endogenous molecular mechanisms that coordinate daily rhythms in gene expression, cellular activities, and physiological functions with external day/night cycles. Breakdown of circadian rhythms such as sleep/wake cycles is associated with the onset of several neurological diseases; however, it is not clear whether disruption of rhythms is a...
Since its inception as a laboratory animal in the early 1970s, the zebrafish has proven itself a rising star in the world of comparative biomedical sciences due to its short generation time, ease of care, external fertilization, and transparent larvae. In a very few decades, the zebrafish has been utilized...