The sense of smell allows terrestrial animals to collect information about the chemical nature of their environment through the detection of airborne molecules. In humans smell is believed to play an important role in protecting the organism from environmental hazards such as fire, gas leaks and spoiled food, in determining the flavor of foods, and perhaps in infant-parent bonding. In addition, the study of human olfaction is relevant to a number of medical problems that result in olfactory dysfunction, which can affect nutritional state, and to the study of the etiology of neurodegenerative diseases which manifest themselves in the olfactory epithelium. Although much is known about behavioral aspects of human olfaction, little is understood about the underlying cellular mechanisms in humans. Here we report that viable human olfactory neurons (HON) can be isolated from olfactory tissue biopsies, and we find that HON respond to odorants with an increase in intracellular calcium concentration ([Cai]).

We found that error in speed control rises as a result of friction between the catheter and the model wall. Path reconstruction error depends on the model's cross-sectional diameter, the properties of the catheter insertion mechanism, the magnetic sensor and the system guidance technique.

Ion channels in the basolateral membrane of rabbit parietal cells in isolated gastric glands were studied by the patch clamp technique. Whole-cell current-clamp recordings showed that the membrane potential (Em) changed systematically as a function of the chloride concentrations of the basolateral bathing solution ([Cl-]0), and of the pipette (intracellular) solution. The relationship between Em and [Cl-]0 was not affected by additions of histamine, dibutyryl-cAMP, 4-acetoamido-4'-isothiocyanostilbene-2,2'-disulfonic acid and diphenylamine-2-carboxylate. The whole-cell Cl- conductance was insensitive to voltage. In cell-attached and cell-free patch membranes, however, single Cl- channel opening events could not be observed. The value of Em depended little on the basolateral K+ concentration, but inward-rectifier K+ currents were observed in the whole-cell configuration, activated by hyperpolarizing pulses and inhibited by extracellular Ba2+. In cell-attached and cell-free patches, openings of single inward-rectifier K+ channels and non-selective cation channels were infrequently recorded. Neither cAMP nor Ca2+ activated these cation channels. The single K+ channel conductance was about 230 pS under the symmetrical high K+ conditions and was inhibited by intracellular tetraethylammonium ions (TEA). The non-selective cation channel had a voltage-independent single conductance of 22 pS and was not inhibited by TEA.

SUMMARY1. C1-channels in the basolateral membrane of non-stimulated parietal cells in isolated rabbit gastric glands were studied by patch-clamp and noise analysis techniques.2. Voltage-independent whole-cell currents were recorded from parietal cells equilibrated with Cl--containing solutions. Upon reducing the Cl-concentration of the basolateral bathing solution, the current-voltage curve was rapidly shifted to the right. The reversal potential changed according to changes in the equilibrium potential for Cl-.3. A Cl-channel blocker, 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB) inhibited whole-cell Cl-currents. The half-maximal inhibitory concentration of NPPB was 300,aM, and the inhibition was reversible (at < 200 /tM). Another Cl-channel blocker, 4-acetamido-4'-isothiocyanatostilbene-2,2'-dilsulphonic acid or diphenylamine-2-carboxylate was much less effective.4. The power spectra of whole-cell Cl-current fluctuations contained one Lorentzian component. The single Cl-channel conductance was estimated to be 0 35 pS by the variance noise analysis, which is in agreement with the value obtained by a method of power spectrum analysis (0 29 pS).5. The addition of arachidonic acid (10 /iiM) to the basolateral medium markedly increased the whole-cell Cl-current. The combined application of a cyclo-oxygenase inhibitor, indomethacin (50,uM), and a lipoxygenase inhibitor, esculetin (100 /tM), increased the Cl-current, whereas the administration of a phospholipase A2 inhibitor, mepacrine (100 /tM), significantly decreased the whole-cell Cl-current. 6. A sizeable increase in the whole-cell Cl-current was also induced by a metabolite of arachidonic acid, prostaglandin E2 (10 aM), but not by leukotriene B4

The cross-correlation search has been previously applied to map the gravitational wave (GW) stochastic background in the sky and also to target GW from rotating neutron stars/pulsars. Here we investigate how the cross-correlation method can be used to target a small region in the sky spanning at most a few pixels, where a pixel in the sky is determined by the diffraction limit which depends on the (i) baseline joining a pair of detectors and (ii) detector bandwidth. Here as one of the promising targets, we consider the Virgo cluster -a "hot spot" spanning few pixels -which could contain, as estimates suggest ∼ 10 11 neutron stars, of which a small fraction would continuously emit GW in the bandwidth of the detectors. For the detector baselines, we consider advanced detector pairs among LCGT, LIGO, Virgo, ET etc. Our results show that sufficient signal to noise can be accumulated with integration times of the order of a year. The results improve for the multibaseline search. This analysis could as well be applied to other likely hot spots in the sky and other possible pairs of detectors. PACS numbers: 95.85.Sz,04.80.Nn,07.05.Kf,95.55.Ym