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Cross-Comparison of Three Electromyogram Decomposition Algorithms Assessed with Simulated and Experimental DataDai, Chenyun 19 April 2013 (has links)
High quality automated electromyogram (EMG) decomposition algorithms are necessary to insure the reliability of clinical and scientific information derived from them. In this work, we used experimental and simulated data to analyze the decomposition performance of three publicly available algorithms¡ªEMGLAB [McGill et al., 2005] (single-channel data only), Fuzzy Expert [Erim and Lin, 2008] and Montreal [Florestal et al., 2009]. Comparison data consisted of quadrifilar needle EMG from the tibialis anterior of 12 subjects (young and elderly) at three contraction levels (10, 20 and 50% MVC), single-channel clinical EMG from the biceps brachii of 10 subjects, and matched simulation data for both electrode types. Performance was assessed via agreement between pairs of algorithms for experimental data and accuracy with respect to the known decomposition for simulated data. For the quadrifilar data, median agreements between the Montreal and Fuzzy Expert algorithms at 10, 20 and 50% MVC were 95.7, 86.4 and 64.8%, respectively. For the single-channel data, median agreements between pairs of algorithms were 94.9% (Montreal vs. Fuzzy Expert) and 100% (EMGLAB vs. either Montreal or Fuzzy Expert). Accuracy on the simulated data exceeded this performance. Agreement/accuracy was strongly related to trial Complexity, as was motor unit signal to noise ratio, Dissimilarity and Decomposability Index. When agreement was high between algorithm pairs applied to the simulated data, so was the individual accuracy of each algorithm.
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The use of δ15N to examine past mangrove stand structuresGudeman, Stephanie M. 02 June 2009 (has links)
Twin Cays, Belize, is dominated by Rhizophora mangle L. (red mangrove). Tall (>5m in height) R. mangle are located along the fringe of the island and dwarf R. mangle grow in the interior of the island. These stand structures can be differentiated using δ13C and δ15N analysis (mean tall δ13C = -28 ‰, mean tall δ15N = 0‰; mean dwarf δ13C = -25‰, mean dwarf δ15N = -10‰), which may also prove useful in examining past mangrove stand structures from sediment cores. 15N label was traced in R. mangle leaves in a laboratory and field experiment over three months. The 15N label was examined to determine distribution of nitrogen in various biochemical fractions of the leaf and to verify if nitrogen is fractionated in a predictable manner over time. This information could be beneficial in examining past mangrove stand structures. Experimental data indicate that nitrogen is mobile within each biochemical fraction of the R. mangle leaf over time and a measurable amount of nitrogen exists in each fraction after 3 months of incubation. Nitrogen immobilization was evident in each experiment, as the δ15N values decreased ~200‰ in each of the labeled fractions of the laboratory experiment, which was mirrored by an increase in δ15N in the control samples. The amount of nitrogen in the biochemical fractions of the field experiment varied over time either increasing or decreasing, which may be due to the various environmental conditions such as tidal fluctuation, temperature, oxygen concentrations and microbial activity. The δ15N signature of the residual nitrogen fraction (δ15N = 87‰) reflected that of the bulk fraction (δ15N = 133‰) in the laboratory experiment as well as in the field experiment (residual nitrogen δ15N = 759‰, bulk δ15N = 770‰). To use isotope analysis to examine past mangrove stand structures it is essential that the original signature be maintained over time. The results of this study indicated that the simple interpretation of nitrogen isotopes may not be useful in examining past mangrove stand structures due to the variation over time, although this type of analysis may be considered if coupled with additional proxies and diagenetic factors are taken into account.
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The use of δ15N to examine past mangrove stand structuresGudeman, Stephanie M. 02 June 2009 (has links)
Twin Cays, Belize, is dominated by Rhizophora mangle L. (red mangrove). Tall (>5m in height) R. mangle are located along the fringe of the island and dwarf R. mangle grow in the interior of the island. These stand structures can be differentiated using δ13C and δ15N analysis (mean tall δ13C = -28 ‰, mean tall δ15N = 0‰; mean dwarf δ13C = -25‰, mean dwarf δ15N = -10‰), which may also prove useful in examining past mangrove stand structures from sediment cores. 15N label was traced in R. mangle leaves in a laboratory and field experiment over three months. The 15N label was examined to determine distribution of nitrogen in various biochemical fractions of the leaf and to verify if nitrogen is fractionated in a predictable manner over time. This information could be beneficial in examining past mangrove stand structures. Experimental data indicate that nitrogen is mobile within each biochemical fraction of the R. mangle leaf over time and a measurable amount of nitrogen exists in each fraction after 3 months of incubation. Nitrogen immobilization was evident in each experiment, as the δ15N values decreased ~200‰ in each of the labeled fractions of the laboratory experiment, which was mirrored by an increase in δ15N in the control samples. The amount of nitrogen in the biochemical fractions of the field experiment varied over time either increasing or decreasing, which may be due to the various environmental conditions such as tidal fluctuation, temperature, oxygen concentrations and microbial activity. The δ15N signature of the residual nitrogen fraction (δ15N = 87‰) reflected that of the bulk fraction (δ15N = 133‰) in the laboratory experiment as well as in the field experiment (residual nitrogen δ15N = 759‰, bulk δ15N = 770‰). To use isotope analysis to examine past mangrove stand structures it is essential that the original signature be maintained over time. The results of this study indicated that the simple interpretation of nitrogen isotopes may not be useful in examining past mangrove stand structures due to the variation over time, although this type of analysis may be considered if coupled with additional proxies and diagenetic factors are taken into account.
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Thermal decomposition of (presumed) bismethylene diazeneHawke, David H. Dervan, Peter B. January 1977 (has links)
Thesis (Masters)--California Institute of Technology, 1977. / Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 02/09/10. Includes bibliographical references.
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Forest soil organic matter of a European transect : carbon mineralization in response to temperatureCalias, Pangiotis January 1997 (has links)
No description available.
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Accounting for Uncovered Interest Rate Parity - The Permanent and Transitory Decomposition Approach張惠玲 Unknown Date (has links)
In most of the empirical research about the uncovered interest rate parity (UIP), estimation of the condition at short horizons rejects this theoretical proposition and presents just opposite outcome, while estimation at long horizons reports more consistent results with the proposition. Based on the belief that permanent components may convey more information in the UIP condition, we adopt in this thesis the permanent-transitory decomposition approach introduced by Gonzalo
and Granger (1995) to estimate the common long memory components
of interest rates and that of exchange rate. We then re-evaluate the UIP condition using the decomposed permanent and transitory parts, respectively. Our results reinforce the stylized facts existing in the literature, while it remains to be answered why empirical evidence does not favor the UIP condition. / In most of the empirical research about the uncovered interest rate parity (UIP), estimation of the condition at short horizons rejects this theoretical proposition and presents just opposite outcome, while estimation at long horizons reports more consistent results with the proposition. Based on the belief that permanent components may convey more information in the UIP condition, we adopt in this thesis the permanent-transitory decomposition approach introduced by Gonzalo
and Granger (1995) to estimate the common long memory components
of interest rates and that of exchange rate. We then re-evaluate the UIP condition using the decomposed permanent and transitory parts, respectively. Our results reinforce the stylized facts existing in the literature, while it remains to be answered why empirical evidence does not favor the UIP condition.
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Solid state decomposition of alkyloxy furoic acidsKothari, Rohit Chunilal. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 153-167).
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The thermal decomposition of methyl vinyl etherHarris, Jack Edward January 1942 (has links)
[No abstract submitted] / Science, Faculty of / Chemistry, Department of / Graduate
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Quantum yields of decomposition in the photolytic oxidation of methyl mercaptan, dimethyl sulphide and dimethyl disulphideSheraton, Donald Frederick January 1979 (has links)
The Kraft pulping process produces vast quantities of sulphide vapours which are released to atmosphere. The major components are methyl mercaptan, hydrogen sulphide, dimethyl sulphide and dimethyl disulphide. The fate of these compounds in the atmosphere and the kinetics of their degradation processes in the atmosphere are useful in the modeling of the environment of areas proximate to Kraft pulp mills. The information may also be useful in developing pollution abatement processes.
The photolytic oxidation of methyl mercaptan, dimethyl sulphide and dimethyl disulphide was studied in a batch photolysis apparatus. Short wavelength ultra-violet light was provided by a deuterium discharge lamp and monitored by a monochromator equipped with an extended response photo-multiplier tube. Sulphide concentrations were determined on a gas chromatograph equipped with a flame photmetric detector having 365 nm sulphur response.
The rate of reaction of methyl mercaptan was found to be a linear function of the photon absorption rate and exhibited a quantum yield of decomposition of 13.9. The methyl mercaptan photo-oxidation rate was found to be unaffected by increased oxygen concentration, decreased atmospheric pressure or the presence of excess sulphur dioxide.
The quantum yield of dimethyl sulphide decomposition was found to be dependent upon atmospheric pressure. A pressure of one atmosphere gave a quantum yield of 4 and the yield increased to 8 at one-quarter atmosphere. The quantum yield of dimethyl disulphide.was found to be 1.9 at atmospheric pressure at a concentration of 7.04 x 10⁻⁵M.
The apparatus was also operated in a configuration which allowed the detection of light emitted at 90° to the path of illumination. A slow developing emission was found for dimethyl sulphide, hydrogen sulphide and •sulphur dioxide. Only slight emission was found for methyl mercaptan and dimethyl disulphide.
The emission from dimethyl sulphide was found to be linearily dependent upon the nitrogen pressure of a dry nitrogen atmosphere. The emission is attributed to aerosol formation and is due to the light scattered from particles in the reaction matrix. / Science, Faculty of / Chemistry, Department of / Graduate
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Thermal Decomposition of Alkyllithium Compounds in the Pure StateLin, Jacob Wen-pin 01 1900 (has links)
This thesis is concerned with the thermal decomposition of a series of alkyllithium compounds in the pure state in an attempt to determine the relative stability of alkyllithium compounds and to examine the mechanism of the elimination reaction.
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