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Release Condition (release + condition)
Selected AbstractsCircle hooks, ,J' hooks and drop-back time: a hook performance study of the south Florida recreational live-bait fishery for sailfish, Istiophorus platypterusFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2007E. D. PRINCE Abstract, This study evaluates the performance of two types of non-offset circle hooks (traditional and non-traditional) and a similar-sized ,J' hook commonly used in the south Florida recreational live-bait fishery for Atlantic sailfish, Istiophorus platypterus (Shaw). A total of 766 sailfish were caught off south Florida (Jupiter to Key West, FL, USA) to assess hook performance and drop-back time, which is the interval between the fish's initial strike and exertion of pressure by the fisher to engage the hook. Four drop-back intervals were examined (0,5, 6,10, 11,15 and >15 s), and hook performance was assessed in terms of proportions of successful catch, undesirable hook locations, bleeding events and undesirable release condition associated with physical hook damage and trauma. In terms of hook performance, the traditionally-shaped circle hook had the greatest conservation benefit for survival after release. In addition, this was the only hook type tested that performed well during each drop-back interval for all performance metrics. Conversely, ,J' hooks resulted in higher proportions of undesirable hook locations (as much as twofold), bleeding and fish released in undesirable condition, particularly during long drop-back intervals. Non-traditional circle hooks had performance results intermediate to the other hook types, but also had the worst performance relative to undesirable release condition during the first two drop-back intervals. Choice of hook type and drop-back interval can significantly change hook wounding, and different models of non-offset circle hooks should not be assumed to perform equivalently. [source] Target-dependent modulation of neurotransmitter release in cultured Helix neurons involves adhesion moleculesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2001Mirella Ghirardi Abstract The secretory capabilities of the serotonergic neuron C1 of cerebral ganglion of Helix pomatia were markedly reduced when it was cultured in contact with the wrong target neuron, C3. When the neuron B2, one of its physiological targets, was micromanipulated within the network made of intermingled neurites originating from the axonal stumps of both C1 and C3 neurons, C1 increased the amount of the evoked transmitter release, which, after 30 min, reached the level observed when cocultured with the appropriate target. The removal of the appropriate target brought C1 back to the low release condition. By imaging C1 neurites with a fluorescent dye, morphological changes involving a local increase in the number of varicosities could be observed as early as 30 min after contact with the appropriate target. Monoclonal antibody 4E8 against apCAM, a family of Aplysia adhesion molecules, recognizes apCAM-like molecules of the Helix central nervous system on immunocytochemistry and Western blot analysis. The contact with the appropriate target previously incubated in a 4E8 solution, which did not interfere with its capacity to respond to serotonin, failed to increase the transmitter release of C1 cocultured in the presence of the wrong target, C3. These results suggest that the apCAM-like antigens bound to the target membrane participate in the molecular processes responsible for the assembly of the "release machinery" present in the functional presynaptic structure. J. Neurosci. Res. 65:111,120, 2001. © 2001 Wiley-Liss, Inc. [source] Identification of objects in an acoustic wave guide inversion II: Robin,Dirichlet conditionsMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 4 2006Doo-Sung Lee Abstract In this paper we investigate the unknown body problem in a wave guide where one boundary has a pressure release condition and the other an impedance condition. The method used in the paper for solving the unknown body inverse problem is the intersection canonical body approximation (ICBA). The ICBA is based on the Rayleigh conjecture, which states that every point on an illuminated body radiates sound from that point as if the point lies on its tangent sphere. The ICBA method requires that an analytical solution be known exterior to a canonical body in the wave guide. We use the sphere of arbitrary centre and radius in the wave guide as our canonical body. We are lead then to analytically computing the exterior solution for a sphere between two parallel plates. We use the ICBA to construct solutions at points ranging over the suspected surface of the unknown object to reconstruct the unknown object using a least-squares matching of computed, acoustic field against the measured, scattered field. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of parameterized quadratic eigenvalue problems in computational acoustics with homotopic deviation theoryNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 6 2006F. Chaitin-Chatelin Abstract This paper analyzes a family of parameterized quadratic eigenvalue problems from acoustics in the framework of homotopic deviation theory. Our specific application is the acoustic wave equation (in 1D and 2D) where the boundary conditions are partly pressure release (homogeneous Dirichlet) and partly impedance, with a complex impedance parameter ,. The admittance t = 1/, is the classical homotopy parameter. In particular, we study the spectrum when t , ,. We show that in the limit part of the eigenvalues remain bounded and converge to the so-called kernel points. We also show that there exist the so-called critical points that correspond to frequencies for which no finite value of the admittance can cause a resonance. Finally, the physical interpretation that the impedance condition is transformed into a pressure release condition when |t| , , enables us to give the kernel points in closed form as eigenvalues of the discrete Dirichlet problem. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||