scholarly journals Autonomic effects on the spectral analysis of heart rate variability after exercise

2009 ◽  
Vol 297 (4) ◽  
pp. H1421-H1428 ◽  
Author(s):  
Jason Ng ◽  
Sri Sundaram ◽  
Alan H. Kadish ◽  
Jeffrey J. Goldberger
Keyword(s):  
Frequency Domain ◽  
High Frequency ◽  
Frequency Domain Analysis ◽  
Mean Square ◽  
Rr Intervals ◽  
Autonomic Blockade ◽  
Frequency Components ◽  
Highly Correlated ◽  
Relationship Of ◽  
The Relationship

Although frequency-domain analysis of heart rate variability (HRV) has been performed in the setting of exercise and recovery from exercise, the relationship of specific frequency components to sympathetic and parasympathetic inputs has not been validated in this setting. The aim of this study is to evaluate the relationship of frequency components of HRV to sympathetic and parasympathetic modulation in the setting of recovery after exercise using selective autonomic blockade. Normal subjects ( n = 27, 17 men, 53 ± 7 yr old) underwent bicycle stress testing on four separate days. On day 1, a baseline study without autonomic blockade was performed. On days 2 through 4, either β-adrenergic, parasympathetic, or double blockade was administered during exercise and completed 3 min before recovery. Continuous ECG was recorded for 5 min starting from the end of exercise. Time- and frequency-domain measures of HRV were computed for each of the five 1-min segments of RR intervals. Parasympathetic blockade significantly decreased all the HRV measures compared with baseline ( P < 0.02 for all). Root mean square of successive differences of RR intervals (rMSSD) was increased by β-adrenergic blockade ( P < 0.0002). All the HRV measures except rMSSD showed increases with time after the first minute of recovery. The low frequency-to-high frequency ratio did not respond to autonomic blockade or to recovery time, consistent with the expected changes in sympathovagal influence. Root mean square (detrended SD) and rMSSD were highly correlated with the square root of the total power ( r = 0.96) and high-frequency power ( r = 0.95), respectively. Although there are marked reductions in the frequency-domain measures in recovery versus rest, the fluctuations in the low- and high-frequency bands respond to autonomic blockade in the expected fashion. Time-domain measures of HRV were highly correlated with frequency-domain measures and therefore provide a computationally more efficient assessment of autonomic influences during recovery from exercise that is less susceptible to anomalies of frequency-domain analysis.

The Relationship of Root Mean Square Value of Electromyography and Isometric Torque of Quadriceps in Normal Subjects

2016 ◽  
Vol 26 (1) ◽  
pp. 58
Author(s):  
Qiurong XIE ◽  
Zheng JIANG ◽  
Qinglu LUO ◽  
Jie LIANG ◽  
Xiaoling WANG ◽  
...  
Keyword(s):  
Root Mean Square ◽  
Normal Subjects ◽  
Mean Square ◽  
Isometric Torque ◽  
Relationship Of ◽  
The Relationship

Relationship of Manifest Aggressiveness to Aggressive Word Associations

1969 ◽  
Vol 25 (3) ◽  
pp. 711-714 ◽  
Author(s):  
Russell G. Geen ◽  
Robert George
Keyword(s):  
Verbal Behavior ◽  
Social Desirability ◽  
Habit Strength ◽  
Self Report ◽  
Social Desirability Scale ◽  
Word Associations ◽  
Highly Correlated ◽  
Cue Words ◽  
Relationship Of ◽  
The Relationship

A self-report inventory made up of items from the Buss-Durkee manifest aggressiveness scales, the Marlowe-Crowne Social Desirability Scale, and the Masculinity-Femininity scale of the Guilford-Zimmerman Temperament Survey was administered to 72 men along with a test of verbal associations to aggressive and neutral cue words. The number of aggressive associations made to aggressive cue words was highly correlated with over-all manifest aggressiveness and with two of the aggressiveness subscales. The results were discussed in terms of the relationship of aggressiveness habit strength to verbal behavior.

Comparison of Two Sociometric Devices for Measuring Personality Integration

1971 ◽  
Vol 29 (3_suppl) ◽  
pp. 1035-1039
Author(s):  
Logan Wright
Keyword(s):  
Locus Of Control ◽  
The Other ◽  
Self Concept ◽  
College Age ◽  
Functional Measure ◽  
Personality Integration ◽  
Validity Measures ◽  
Highly Correlated ◽  
Relationship Of ◽  
The Relationship

A comparison was made of two sociometric measures of personality integration. Contrary to prediction, the more brief, 6-item PIRT scale was significantly more reliable ( r11 = .84) than the lengthier 30-item ESD scale ( r11 = .74). Also contrary to prediction, neither test was more highly correlated than the other (and therefore more valid) with any of 8 construct-validity measures. It was concluded that the PIRT was the more functional measure and therefore recommended for use in future personality integration research. Earlier results concerning the relationship of personality integration to self-concept and environmental contact, as well as locus of control and locus of evaluation in college-age females, were replicated.

High Frequency Response of Beams

1975 ◽  
Vol 42 (4) ◽  
pp. 805-808 ◽  
Author(s):  
R. P. Parker ◽  
V. H. Neubert
Keyword(s):  
Experimental Data ◽  
High Frequency ◽  
Rates Of Convergence ◽  
Series Solutions ◽  
Timoshenko Theory ◽  
High Frequency Response ◽  
Lateral Response ◽  
Mode Solution ◽  
Relationship Of ◽  
The Relationship

In developing the relationship of the normal mode solution for a vibrating rod to the pyrotechnic shock problem, a detailed analysis is presented using the Timoshenko theory to obtain the transient lateral response of a cylindrical rod with free ends to a short duration half sine pulse of either moment or shear applied to one end. Two different series solutions are used and the rates of convergence are compared near the boundary. Results are compared with experimental data.

scholarly journals A Possible Relationship Between Toxicity and Carcinogenicity

1986 ◽  
Vol 5 (2) ◽  
pp. 137-151 ◽  
Author(s):  
L. Zeise ◽  
E. A.C. Crouch ◽  
R. Wilson
Keyword(s):  
Acute Toxicity ◽  
National Cancer Institute ◽  
Chronic Toxicity ◽  
Positive Finding ◽  
National Toxicology Program ◽  
Technical Report Series ◽  
Technical Report ◽  
Highly Correlated ◽  
Relationship Of ◽  
The Relationship

Carcinogenic response is compared to noncarcinogenic toxicity in that group of chemicals tested by the National Cancer Institute (NCI) and National Toxicology Program (NTP) between 1976 and 1982 and reported in the Carcinogenesis Technical Report Series. A positive finding of carcinogenicity in the bioassay is correlated with the degree of noncarcinogenic chronic toxicity of the dose applied. Comparisons of acute toxicity (LD50) with carcinogenic potency show that they are correlated, but the correlation may in part be an artifact, since doses used in the NCI/NTP carcinogenesis bioassays are toxic and because reliable measures of potency can only be derived for positive carcinogenic responses. The high correlations for certain classes of chemicals and the relationship of chronic toxicity to positive carcinogenic finding suggest that these relationships are more than spurious. Since toxicities in different species are highly correlated, these findings imply that carcinogenicities in different species are also correlated.

Regime Change of the Boreal Summer Hadley Circulation and Its Connection with the Tropical SST

2011 ◽  
Vol 24 (15) ◽  
pp. 3867-3877 ◽  
Author(s):  
Ran Feng ◽  
Jianping Li ◽  
Jincheng Wang
Keyword(s):  
High Frequency ◽  
Regime Change ◽  
Hadley Circulation ◽  
Warm Pool ◽  
Boreal Summer ◽  
Tropical Atlantic ◽  
Asymmetric Mode ◽  
Pacific Warm Pool ◽  
Highly Correlated ◽  
Relationship Of

Abstract The year-to-year variability of the boreal summer [June–August (JJA)] Hadley circulation (HC) is dominated by an asymmetric mode centered in the Northern Hemisphere (AMN) and a quasi-symmetric mode centered at 5°N (QSM). The regime change of the JJA HC is revealed by the phase reversal of the time series of the AMN, showing significant weakening of the northern part of the JJA HC and a reversed seesaw relationship of the zonal-mean updraft over 10°–20°N and around the equator. This transition is accompanied by the southward retreat of the HC core and is well correlated with the weakening of tropical summer monsoons. The strong warming trends of the sea surface temperature over the tropical Atlantic and Indo–west Pacific warm pool play an important role in the regime change of the JJA HC. The high-frequency interannual variability of the JJA HC, however, is mainly featured by the QSM and is highly correlated with the Niño-3.4 index, implying that ENSO’s influence is mainly on the high-frequency interannual time scale.

Monte Carlo Study of Dispersive Transport in Glassy Electrolytes

1994 ◽  
Vol 369 ◽  
Author(s):  
D. Knödler ◽  
P. Pendzig ◽  
W. Dieterich
Keyword(s):  
Monte Carlo ◽  
Lattice Gas ◽  
Monte Carlo Study ◽  
Power Laws ◽  
Dispersive Transport ◽  
Coulombic Interactions ◽  
Highly Correlated ◽  
Relationship Of ◽  
The Relationship ◽  
Network Glasses

AbstractA lattice-gas model is presented, where ions are diffusing in an energy landscape due to immobile, randomly placed counterions. All Coulombic interactions are taken into account.By Monte Carlo simulations we obtain the ac-conductivity, which shows strong dispersion in the form of power-laws. In a separate study we investigate a restricted model, where long-range diffusion is suppressed. These calculations suggest that the response at high frequencies can be interpreted in terms of highly correlated, local motions of dipolar character. Conductivity exponents n1 near unity or even exceeding unity arefound in that regime. We discuss the relationship of these results to experiments on ionic transport in alkali-doped network glasses.

Reliance on Visual Imagery and its Relation to Mental Rotation

1997 ◽  
Vol 85 (2) ◽  
pp. 431-434 ◽  
Author(s):  
Doris C. Weatherly ◽  
Steven E. Ball ◽  
James R. Stacks
Keyword(s):  
Mental Rotation ◽  
Response Latency ◽  
High Frequency ◽  
Visual Imagery ◽  
Learning Effect ◽  
Low Frequency ◽  
Computer Screen ◽  
The Right ◽  
Relationship Of ◽  
The Relationship

The relationship of habitual use of visual imagery and mental rotation was investigated. Reliance on Visual Imagery scores were used to define subjects as high frequency or low frequency visualizers. During the mental rotation task, subjects indicated if a pair of 2-dimensional stimulus figures displayed on a computer screen were identical or mirror-images. Figures on the right were rotated in relation to those on the left by 0, 60, 120, or 180°. Data supported the prediction that subjects who report high use of imagery would perform the task with greater accuracy ( z=1.97, p<.05) than subjects who reported low use. The imagery groups did not differ in response latency ( z = .91, p<.36). A comparison of performance on Trials 1 to 24 with performance on Trials 115-138 indicated a learning effect in both accuracy ( z = 7.58, p<.01) and latency ( z = 9.72, p<.01) for all subjects.

The Relationship between Frequency Domain Blind Source Separation and Frequency Domain Adaptive Beamformer

2014 ◽  
Vol 490-491 ◽  
pp. 654-662
Author(s):  
Si Chong Qian ◽  
Yang Xiang
Keyword(s):  
Frequency Domain ◽  
Mean Square Error ◽  
Blind Source Separation ◽  
Array Signal Processing ◽  
Source Separation ◽  
Adaptive Beamforming ◽  
Separation Performance ◽  
Mean Square ◽  
The Mean ◽  
The Relationship

As two important methods of array signal processing, blind source separation and beamforming can extract the target signal and suppress interference by using the received information of the array element. In the case of convolution mixture of sources, frequency domain blind source separation and frequency domain adaptive beamforming have similar signal model. To find the relationship between them, comparison between the minimization of the off-diagonal components in the BSS update equation and the minimization of the mean square error in the ABF had been made from the perspective of mathematical expressions, and find that the unmixing matrix of the BSS and the filter coefficients of the ABF converge to the same solution in the mean square error sense under the condition that the two source signals are ideally independent. With MATLAB, the equivalence in the frequency domain have been verified and the causes affecting separation performance have been analyzed, which was achieved by simulating instantaneous and convolution mixtures and separating mixture speech in frequency-domain blind source separation and frequency domain adaptive beamforming way.

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