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Detection Range (detection + range)

Distribution by Scientific Domains

Chemistry	50%
Earth and Environmental Science	33%

Selected Abstracts

Riverine, estuarine and marine migratory behaviour and physiology of wild and hatchery-reared coho salmon Oncorhynchus kisutch (Walbaum) smolts descending the Campbell River, BC, Canada

JOURNAL OF FISH BIOLOGY, Issue 3 2008
C. M. Chittenden
Eighty coho salmon Oncorhynchus kisutch smolts (40 wild and 40 hatchery-reared) were surgically implanted with acoustic transmitters and released into the Quinsam River over 2 days. Differences in physiology, travel time and migratory behaviour were examined between wild and hatchery-reared fish. In addition, tagged and control fish of both wild and hatchery-reared stock were raised for 3 months following surgery to compare survival and tag retention. Detection ranges of the acoustic receivers were tested in the river, estuary and ocean in a variety of flow conditions and tide levels. Receivers were placed in the river, estuary and up to 50 km north and south from the river mouth in the marine environment. Wild smolts were significantly smaller by mass, fork length and condition factor than hatchery-reared smolts and exhibited significantly higher levels of sodium, potassium and chloride in their blood plasma than hatchery-reared smolts. The gill Na+K+ -ATPase activity was also significantly higher in the wild coho smolts at the time of release. Ninety-eight per cent of wild and 80% of hatchery-reared fish survived to the estuary, 8 km downstream of the release site. No difference was found in migration speed, timing or survival between smolts released during daylight and those released after dark. Wild smolts, however, spent less time in the river and estuary, and as a result entered the ocean earlier than hatchery-reared smolts. Average marine swimming speeds for wild smolts were double those of their hatchery-reared counterparts. While hatchery smolts dispersed in both a northward and southward direction upon entering the marine environment, the majority of wild smolts travelled north from the Campbell River estuary. The wild coho salmon smolts were more physiologically fit and ready to enter sea water than the hatchery-reared smolts, and as a result had higher early survival rates and swimming speeds. [source]

Electrochemical Determination of a Free Chlorine Residual Using Cathodic Potential-Step Chronocoulometry

ELECTROANALYSIS, Issue 8 2005
Shin-ya Kishioka
Abstract The cathodic reaction of chlorine residual (CR) combined with anodic pre-electrolysis enables the quantification of CR as a gaseous chlorine. Potential-step chronocoulometry was successfully applied to extend the CR detection range. [source]

Recent trend of the partial discharge measurement technique using the UHF electromagnetic wave detection method

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 5 2007
Masayuki Hikita Member
Abstract The ultra high frequency (UHF) electromagnetic wave detection method has been widely studied and used in partial discharge (PD) measurement and as a diagnostic technique for insulation performance in gas-insulated switchgears (GIS) and transformers. The UHF method has advantages such as high sensitivity, wide detection range and reduced external disturbances. On the other hand, there are still some issues to be solved in the UHF methods, such as a clear understanding of the propagation characteristics of electromagnetic waves arising from the structure of the equipment, optimization of antenna design, calibration of charge, etc. This article deals with the present status and future trend of the technology of this promising UHF method of PD measurement, together with recent activities and results from our laboratory. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

A combination of neutral loss and targeted product ion scanning with two enzymatic digestions facilitates the comprehensive mapping of phosphorylation sites

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 15 2007
Juan Casado-Vela
Abstract We propose here a new strategy for the exhaustive mapping of phosphorylation sites in the Xenopus laevis Cdc25 phosphatase, which regulates cell cycle progression in eukaryotic cells. Two different MS analyses in a linear IT were used to identify the phosphorylated residues. First, a data-dependent neutral loss (DDNL) analysis triggered the fragmentation of peptides that show enhanced neutral loss of phosphoric acid. Second, a targeted product ion scanning (TPIS) mass analysis was carried out in which MS2 events are triggered for specific m/z values. Full coverage of the protein sequence was obtained by combining the two analyses with two enzymatic digestions, trypsin and chymotrypsin, yielding a comprehensive map of the phosphorylation sites. Previous reports have shown Cdc25C to be phosphorylated by Cdc2,cyclin B at four residues (Thr48, Thr67, Thr138 and Ser205). By using this combination of scan modes, we have identified four additional phosphorylation sites (Thr86, Ser99, Thr112 and Ser163) in a recombinant Cdc25C protein containing 198 residues of the NH2 -terminal noncatalytic domain. The sensitivity of this combined approach makes it extremely useful for the comprehensive characterization of phosphorylation sites, virtually permitting complete coverage of the protein sequence with peptides within the mass detection range of the linear IT. [source]

Kinetics of antigen binding to antibody microspots: Strong limitation by mass transport to the surface

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 3 2006
Wlad Kusnezow Dr.
Abstract It is well documented that diffusion has generally a strong effect on the binding kinetics in the microtiter plate immunoassays. However, a systematic quantitative experimental evaluation of the microspot kinetics is still missing in the literature. Our work aims at filling this important gap of knowledge on the example of antigen binding to antibody microspots. A mathematical model was derived within the framework of two-compartment model and applied to the quantitative analysis of the experimental data obtained for typical antibody microspot assays. A strong mass-transport dependence of the antigen-antibody microspot kinetics was identified to be one of the main restrictions of this new technology. The binding reactions are slowed down in the microspot immunoassays by several orders of magnitude as compared with the corresponding well-stirred bulk reactions. The task to relax the mass-transport limitations should thus be one of the most important issues in designing the antibody microarrays. These limitations notwithstanding, the detection range of more than five orders of magnitude and the high sensitivity in the low femtomolar range were experimentally achieved in our study, demonstrating thus an enormous potential of this highly capable technology. [source]

An automated velocity dealiasing method based on searching for zero isodops

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 651 2010
Nan Li
Abstract A new automated velocity dealiasing method based on zero isodop searching has been developed primarily for linear wind fields. Its essence is to partition the radial velocity field obtained with a Doppler radar into two distinct regions of opposite velocity signs by two zero isodops. Zero isodops are searched point by point from the radar origin to the maximum detection range, and the accepted sign of each region separated by the zero isodops is determined. After that, the velocity sign at each gate is compared with the accepted sign of the region wherein the gate is. If they are consistent, the velocity is true; otherwise it is dealiased. Dealiasing results in real cases indicate that the new algorithm is practicable and effective, especially on aliasing lack of references affected by discontinuous echo or range folding, which is difficult for traditional methods of space continuity checking. Copyright © 2010 Royal Meteorological Society [source]