There has been an increasing interest in creating short-range, low data-rate underwater wireless sensor networks for scientific marine exploration and monitoring. However, the lack of an inexpensive, low-power, underwater acoustic modem is preventing the proliferation of these sensor networks. Thus, we are building an underwater acoustic modem that considers cost and power at every level, from ...

Cholangiocytes absorb and secrete fluid, modifying primary canalicular bile. In several Cl(-)-secreting epithelia, Na(+)-K(+)-2Cl(-) cotransport is a basolateral Cl(-) uptake pathway facilitating apical Cl(-) secretion. To determine if cholangiocytes possess similar mechanisms independent of CO2/HCO, we assessed Cl(-)-dependent secretion in rat liver isolated polarized bile duct units (IBDUs) b...

In this paper, a multiple-access spread-spectrum communication system using binary frequency shift keying (BFSK) or M -ary frequency shift keying (MFSK), and noncoherent demodulation is considered. In contrast to previous work typically assuming that the FSK tones are non-overlapping after direct-sequence (DS) spreading, here we consider a spread spectrum multiple access (SSMA) system under the...

Arthrofibrosis is a major obstacle to restoring joint function after trauma. The objective of this study was to evaluate montelukast, forskolin, and triamcinolone as possible means of prophylaxis against the formation of arthrofibrosis. Forty-eight rats underwent surgical knee trauma with post-operative immobilization in full flexion. The treatment groups were: control (CTL), oral montelukast (...

OBJECTIVE Because glucocorticoids stimulate leptin release and, at least in vitro, leptin inhibits cortisol secretion, a feedback system between glucocorticoids and leptin has been proposed. However, in humans and non-human primates there are no in vivo studies to support any role for leptin in the control of the hypothalamic-pituitary-adrenal axis. In this study, we investigated the effect of ...

To assess the functional change in adenylyl cyclases (AC) associated with the diabetic state, we investigated AC-mediated relaxations and cAMP production in mesenteric arteries from rats with streptozotocin (STZ)-induced diabetes. The relaxations induced by the water-soluble forskolin (FSK) analog NKH477, which is a putative AC5 activator, but not by the beta-adrenoceptor agonist isoproterenol ...

The role of cAMP/cAMP-dependent protein kinase (PKA) on the late phase of exocytosis has been studied by amperometry on Ba(2+)-stimulated single bovine chromaffin cells. Forskolin (FSK) increases the intracellular cAMP levels in a concentration-dependent manner. Forskolin (100 nM) does not increase the number of exocytotic events, although it significantly increases the net granule content of c...

Physical removal of mammalian cumulus-oocyte complexes (COCs) from ovarian follicles results in spontaneous resumption of meiosis, largely because of a decrease in cAMP concentrations, causing asynchrony between cytoplasmic and nuclear maturation and decreased oocyte developmental competence. The aim of this study was to modulate cAMP concentrations within ovine COCs to delay spontaneous nuclea...