The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Minoru Shinohara - One of the best experts on this subject based on the ideXlab platform.
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low frequency component of rectified emg is temporally correlated with force and Instantaneous Rate of force fluctuations during steady contractions
Muscle & Nerve, 2013Co-Authors: Yasuhide Yoshitake, Minoru ShinoharaAbstract:Introduction: The usefulness of surface EMG for assessing motor output variability during steady contraction is unclear. The purpose of this study was to examine the temporal correlation in signal characteristics between low-frequency components of full-wave rectified EMG (with or without high-pass filtering before rectification) and force fluctuations or the Instantaneous Rate of force fluctuations (dF/dt) during steady contractions. Methods: Fourteen young adults produced steady force with the first dorsal interosseus muscle at various intensities. Cross-correlation functions were calculated between the following signals: <5 Hz: force, dF/dt, and rectified EMG with or without high-pass filtering at 300 Hz before rectification. Results: Rectified EMG correlated better with dF/dt compared with force itself, and high-pass filtering of interference EMG before rectification improved the temporal correlation. Conclusions: The low-frequency component of rectified EMG following high-pass filtering may provide temporal information on the Instantaneous Rate of force fluctuations during steady contractions. Muscle Nerve 47: [?show $1534v]–[?show $1535v], 2013
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Low-frequency component of rectified EMG is temporally correlated with force and Instantaneous Rate of force fluctuations during steady contractions
Muscle & nerve, 2013Co-Authors: Yasuhide Yoshitake, Minoru ShinoharaAbstract:Introduction: The usefulness of surface EMG for assessing motor output variability during steady contraction is unclear. The purpose of this study was to examine the temporal correlation in signal characteristics between low-frequency components of full-wave rectified EMG (with or without high-pass filtering before rectification) and force fluctuations or the Instantaneous Rate of force fluctuations (dF/dt) during steady contractions. Methods: Fourteen young adults produced steady force with the first dorsal interosseus muscle at various intensities. Cross-correlation functions were calculated between the following signals:
Yasuhide Yoshitake - One of the best experts on this subject based on the ideXlab platform.
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low frequency component of rectified emg is temporally correlated with force and Instantaneous Rate of force fluctuations during steady contractions
Muscle & Nerve, 2013Co-Authors: Yasuhide Yoshitake, Minoru ShinoharaAbstract:Introduction: The usefulness of surface EMG for assessing motor output variability during steady contraction is unclear. The purpose of this study was to examine the temporal correlation in signal characteristics between low-frequency components of full-wave rectified EMG (with or without high-pass filtering before rectification) and force fluctuations or the Instantaneous Rate of force fluctuations (dF/dt) during steady contractions. Methods: Fourteen young adults produced steady force with the first dorsal interosseus muscle at various intensities. Cross-correlation functions were calculated between the following signals: <5 Hz: force, dF/dt, and rectified EMG with or without high-pass filtering at 300 Hz before rectification. Results: Rectified EMG correlated better with dF/dt compared with force itself, and high-pass filtering of interference EMG before rectification improved the temporal correlation. Conclusions: The low-frequency component of rectified EMG following high-pass filtering may provide temporal information on the Instantaneous Rate of force fluctuations during steady contractions. Muscle Nerve 47: [?show $1534v]–[?show $1535v], 2013
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Low-frequency component of rectified EMG is temporally correlated with force and Instantaneous Rate of force fluctuations during steady contractions
Muscle & nerve, 2013Co-Authors: Yasuhide Yoshitake, Minoru ShinoharaAbstract:Introduction: The usefulness of surface EMG for assessing motor output variability during steady contraction is unclear. The purpose of this study was to examine the temporal correlation in signal characteristics between low-frequency components of full-wave rectified EMG (with or without high-pass filtering before rectification) and force fluctuations or the Instantaneous Rate of force fluctuations (dF/dt) during steady contractions. Methods: Fourteen young adults produced steady force with the first dorsal interosseus muscle at various intensities. Cross-correlation functions were calculated between the following signals:
Kijong Cho - One of the best experts on this subject based on the ideXlab platform.
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Effects of cadmium, mercury and lead on the survival and Instantaneous Rate of increase of Paronychiurus kimi (Lee) (Collembola)
Applied Soil Ecology, 2007Co-Authors: Jino Son, Mun Il Ryoo, Jinho Jung, Kijong ChoAbstract:Abstract The invertebRate springtail species Paronychiurus kimi (Lee) was selected for use in toxicity testing because it is more ecologically relevant to Korean soils than Folsomia candida Willem, which is the standard animal for toxicity tests. Responses of P. kimi to cadmium, mercury and lead were evaluated in artificial soils following the standardized ISO protocol. Although, reproduction of P. kimi was not as high as that of F. candida , 30 adults produced at least 200 juveniles over 28 days. For each of the three heavy metals, LC 50 and EC 50 for reproduction and NOEC and LOEC for the effect on reproduction and Instantaneous Rate of population increase ( r i ) were also estimated. The 7 days LC 50 was 532, 3.9 and 1322 mg/kg dry soil for cadmium, mercury and lead, respectively. As exposure time increased from 7 to 28 days, the LC 50 values decreased for cadmium but not or only slightly for mercury and lead. The 28 days EC 50 was 60.0 for cadmium, 0.23 for mercury and 428 mg/kg for lead. Significant changes in r i of P. kimi were closely followed by the changes in the sublethal endpoint measured (reproduction) and populations were heading toward extinction ( r i = 0) at concentration of 129, 2.0 and 1312 mg/kg dry soil for cadmium, mercury and lead, respectively. P. kimi was found to be more sensitive to all heavy metals tested than F. candida , confirming its suitability as a bioindicator species for soil toxicological testing in Korea.
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Residual and sublethal effects of fenpyroximate and pyridaben on the Instantaneous Rate of increase of Tetranychus urticae
Crop Protection, 2006Co-Authors: Minsik Kim, Cheolho Sim, Dongyoung Shin, Eunho Suh, Kijong ChoAbstract:Abstract The residual and sublethal effects on Tetranychus urticae Koch adult mortality, and their influence on the reproduction and population growth, were evaluated after exposure to fenpyroximate and pyridaben. The effects on the reproduction were divided into two parts and analyzed sepaRately to determine the contribution to the population growth parameter, the Instantaneous Rate of increase (ri); (1) reproduction on survivors (RS, number of eggs produced), and (2) survivors of progeny (SP, number of immatures developed). The RS and SP were censused 3 and 6 days after treatment, respectively. The direct toxic effects on female adults on treatment with fenpyroximate were always higher and more persistent than those with pyridaben, whereas the effects on the RS and SP were always higher with pyridaben. When the ri was the evaluated endpoint, the RS ri and SP ri for both acaricides declined as the concentration increased, but the reduction was always greater with exposure to pyridaben. The residual effects on the RS ri and SP ri remained strong over the range of residual days tested for both acaricides. The negative values of the SP ri with all the pyridaben treatments indicated that the pyridaben possessed strong and persistent ovicidal activity against T. urticae. The effective concentration (EC50) that reduced the RS ri or SP ri by 50% was always higher than 50% of the lethal fenpyroximate concentration (LC50), but the opposite was true with pyridaben, suggesting that pyridaben treatment would be more devastating to the T. urticae populations than fenpyroximate. The results of this study indicate that fenpyroximate and pyridaben have different direct acute toxicity and reproduction effects in T. urticae, even though they share the same mode of action: mitochondrial electron transport inhibition.
David J Spurgeon - One of the best experts on this subject based on the ideXlab platform.
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comparison of Instantaneous Rate of population increase and critical effect estimates in folsomia candida exposed to four toxicants
Ecotoxicology and Environmental Safety, 2004Co-Authors: Iain N Herbert, Claus Svendsen, Peter K Hankard, David J SpurgeonAbstract:Abstract The Instantaneous Rate of population increase (ri) integRates several life cycle variables into one accessible statistic and has been proposed as a more practical alternative than assembling full life tables in the study of population-level responses to toxicant exposure. In this study the sensitivity of Instantaneous Rate of population increase is compared to critical-effect estimates for populations exposed to four toxicants with different modes of action. Populations of the Collembolan Folsomia candida were exposed to cadmium, copper, pyrene, and chlorpyrifos in artificial soil following the standardized ISO (International Organization for Standardization, Geneva, 1999) protocol. We calculated ri values and LC50, EC50juvenile, and NOEC values for each chemical. Comparison of the relative toxocity of the four chemicals indicated that chlorpyrifos had the lowest values and was thus the most toxic, followed by pyrene, cadmium, and copper. Significant changes in ri were seen to follow closely changes in the sublethal parameter measured (juvenile production) and showed populations in decline at concentrations as low as 40% of the LC50. The study showed ri to be a good measure of population response, and we conclude that the statistic gives a better understanding of effects on a population than through the sole use of traditional critical-effect estimates.
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Comparison of Instantaneous Rate of population increase and critical-effect estimates in Folsomia candida exposed to four toxicants.
Ecotoxicology and environmental safety, 2004Co-Authors: Iain N Herbert, Claus Svendsen, Peter K Hankard, David J SpurgeonAbstract:Abstract The Instantaneous Rate of population increase (ri) integRates several life cycle variables into one accessible statistic and has been proposed as a more practical alternative than assembling full life tables in the study of population-level responses to toxicant exposure. In this study the sensitivity of Instantaneous Rate of population increase is compared to critical-effect estimates for populations exposed to four toxicants with different modes of action. Populations of the Collembolan Folsomia candida were exposed to cadmium, copper, pyrene, and chlorpyrifos in artificial soil following the standardized ISO (International Organization for Standardization, Geneva, 1999) protocol. We calculated ri values and LC50, EC50juvenile, and NOEC values for each chemical. Comparison of the relative toxocity of the four chemicals indicated that chlorpyrifos had the lowest values and was thus the most toxic, followed by pyrene, cadmium, and copper. Significant changes in ri were seen to follow closely changes in the sublethal parameter measured (juvenile production) and showed populations in decline at concentrations as low as 40% of the LC50. The study showed ri to be a good measure of population response, and we conclude that the statistic gives a better understanding of effects on a population than through the sole use of traditional critical-effect estimates.
A Wittneben - One of the best experts on this subject based on the ideXlab platform.
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power allocation schemes for amplify and forward mimo ofdm relay links
IEEE Transactions on Wireless Communications, 2007Co-Authors: I Hammerstrom, A WittnebenAbstract:We consider a two-hop MIMO-OFDM communication scheme with a source, an amplify-and-forward relay, and a destination. We examine the possibilities of power allocation (PA) over the subchannels in frequency and space domains to maximize the Instantaneous Rate of this link if channel state information at the transmitter (CSIT) is available. We consider two approaches: (i) sepaRate optimization of the source or the relay PA with individual per node transmit power constraints and (ii) joint optimization of the source and the relay PA with joint transmit power constraint. We provide the optimal PA at the source (or the relay) with a node transmit power constraint that maximizes the Instantaneous Rate for a given relay (or source) PA. Furthermore, we show that repeating this sepaRate optimization of the source and the relay PA alternately converges and improves the achievable Rate of the considered link. Since the joint optimization of the source and the relay PA is analytically not tractable we use a high SNR approximation of the SNR at the destination. This approximation leads to Rates which are quite tight to the optimum.
