scholarly journals Mechanomyography and acceleration show interlimb asymmetries in Parkinson patients without tremor compared to controls during a unilateral motor task

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Laura V. Schaefer ◽  
Nils Löffler ◽  
Julia Klein ◽  
Frank N. Bittmann
Keyword(s):  
Frequency Ratio ◽  
Biceps Brachii ◽  
Motor Task ◽  
Piezoelectric Sensor ◽  
Oscillatory Behavior ◽  
Variation Coefficient ◽  
Amplitude Variation ◽  
Mean Frequency ◽  
Power Frequency ◽  
The Mean

AbstractThe mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson’s disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.

scholarly journals Two forms of isometric muscle function: Interpersonal motor task supports a distinction between a holding and a pushing isometric muscle action

2020 ◽  
Author(s):  
Laura V Schaefer ◽  
Frank N Bittmann
Keyword(s):  
Muscle Function ◽  
Frequency Ratio ◽  
Neural Control ◽  
Muscle Action ◽  
Triceps Brachii ◽  
Amplitude Variation ◽  
Mean Frequency ◽  
Power Frequency ◽  
The Mean ◽  
Isometric Muscle

AbstractIn sports and movement sciences isometric muscle function is measured by pushing against a stable resistance. However, subjectively one can hold or push isometrically. Several investigations suggest a distinction of those forms. The aim of this study was to investigate, whether or not these two forms of isometric muscle action can be distinguished by objective parameters in an interpersonal setting. 20 subjects were grouped in 10 same sex pairs, in which one partner should perform the pushing isometric muscle action (PIMA) and the other partner executed the holding isometric muscle action (HIMA). The partners were coupled by an interface including a strain gauge and an acceleration sensor. The mechanical oscillations of the triceps brachii (MMGtri) muscle, its tendon (MTGtri) and the abdominal muscle (MMGobl) were recorded by piezoelectric-sensor-based measurement system (mechanomyography (MMG); mechanotendography (MTG)). Each partner performed three 15s (80% MVIC) and two fatiguing trials (90% MVIC) during PIMA and HIMA, respectively (tasks changed in the couple). Regarded parameters to compare PIMA and HIMA were (1) the mean frequency, (2) the normalized mean amplitude, (3) the amplitude variation, (4) the power in the frequency range of 8 to 15 Hz and (5) a special power-frequency ratio and the number of task failures during HIMA or PIMA (partner who quit the task).A “HIMA failure” occurred in 87.5% of trials (p<0.000). No significant differences between PIMA and HIMA were found for the mean frequency and normalized amplitude. The MMGobl showed a significantly higher values of the amplitude variation (15s: p 0.013; fatigue: p=0.007) and of the power-frequency-ratio (15s: p = 0.040; fatigue: p = 0.002) during HIMA and a higher power in the range of 8 to 15 Hz during PIMA (15s: p=0.001; fatigue: p=0.011). MMGtri and MTGtri showed no significant differences.Based on the findings it is suggested that a holding and a pushing isometric muscle action can be distinguished objectively, whereby a more complex neural control is assumed for HIMA.

Features for muscle fatigue computed from electromyogram and mechanomyogram: A new one

2016 ◽  
Vol 230 (12) ◽  
pp. 1096-1105 ◽  
Author(s):  
Şükrü Okkesim ◽  
Kezban Coşkun
Keyword(s):  
Muscle Fatigue ◽  
Frequency Ratio ◽  
Biceps Brachii ◽  
Median Frequency ◽  
Mean Power ◽  
Mean Power Frequency ◽  
Power Frequency ◽  
Ratio Change ◽  
The Mean ◽  
New Feature

Muscle fatigue produces negative effects in the performance and it may lead to a muscle failure. This problem makes the quantitative grading of muscle fatigue a necessity in ergonomic and physiological research. Moreover, the quantitative grading of muscle fatigue is needed to increase work and sport productivity and prevent several accidents that result from muscle fatigue. Even though there are many studies for this aim, there is no quantitative criterion for the evaluation of muscle fatigue. The main reason is that muscle fatigue is a complex physiological situation that is dependent on several parameters. Our aim in this study is to present a new feature to evaluate muscle fatigue and prove the reliability of the new feature by making correlation analyses between this with other features. For this aim, electromyography and mechanomyography signals were simultaneously recorded from the biceps brachii and triceps brachii muscles during the isometric and isotonic contractions of 60 healthy volunteers (30 females, 30 males). The mean power frequency and median frequency, which are used in the literature, were compared to the frequency ratio change, the new measure; correlations between the frequency ratio change and the mean power frequency and median frequency were analysed. There was a high correlation between the features, and frequency ratio change can be used to quantitatively evaluate muscle fatigue.

Crystal Dynamics of the Alloy Cu3Au

1974 ◽  
Vol 52 (22) ◽  
pp. 2235-2239 ◽  
Author(s):  
E. D. Hallman
Keyword(s):  
Inelastic Scattering ◽  
Frequency Ratio ◽  
Large Scale ◽  
Lattice Vibrations ◽  
Frequency Wave ◽  
Mean Frequency ◽  
Resonance Behavior ◽  
The Mean ◽  
Crystal Dynamics ◽  
Disordered Alloy

Using inelastic scattering of slow neutrons, the frequency wave vector dispersion relations for the lattice vibrations in the disordered alloy Cu3Au have been measured at 296 K. The results are similar to those for copper, with the mean frequency ratio (alloy/copper) being 0.778. A Born–von Kármán fit to the data is given. Although detailed measurements of phonon widths have not yet been made, phonons were generally well defined, with no large scale resonance behavior of frequencies or widths observed.

Activation of metabotropic glutamate receptors increase the frequency of spontaneous GABAergic currents through protein kinase A in neonatal rat hippocampal neurons

1995 ◽  
Vol 74 (3) ◽  
pp. 1118-1122 ◽  
Author(s):  
M. Sciancalepore ◽  
F. Stratta ◽  
N. D. Fisher ◽  
E. Cherubini
Keyword(s):  
Protein Kinase ◽  
Protein Kinase A ◽  
Frequency Ratio ◽  
Hippocampal Neurons ◽  
Neonatal Rat ◽  
Synaptic Currents ◽  
Mean Frequency ◽  
Metabotropic Glutamate ◽  
The Mean ◽  
Kinase A

1. The tight-seal whole cell recording technique was used to study the effects of the metabotropic glutamate receptor (mGluR) agonist, trans-1-aminocyclopentane-1,3-dicarboxylic acid (t-ACPD) on spontaneous gamma-aminobutyric acid (GABA)-mediated synaptic currents in neonatal rat CA1 hippocampal neurons in slices obtained from postnatal (P) days P6-P12. 2. Bath application of t-ACPD (3-30 microM), in the presence of kynurenic acid, induced a concentration-dependent increase in frequency but not in amplitude of spontaneous GABAergic currents. The mean frequency ratio (t-ACPD 10 microM over control) was 2.6 +/- 1 (mean +/- SD), whereas the mean amplitude ratio was 1.1 +/- 0.3. 3. The effect of t-ACPD was partially antagonized by the mGluR antagonist (RS)-alpha-methyl-4-carboxyphenylglycine (MCPG, 1 mM). 4. t-ACPD (10-30 microM) did not modify the frequency of miniature GABAergic synaptic currents recorded in tetrodotoxin (the mean frequency ratio of t-ACPD over control was 0.7 +/- 0.3). 5. Forskolin (30 microM), but not its analogue 1,9 dideoxyforskolin (30 microM), mimicked the effect of t-ACPD. Similar effects were obtained with 3-isobutyl-1-methylxanthine (IBMX, 200 microM). 6. The potentiating effect of t-ACPD on spontaneous GABAergic currents was prevented by Rp-cAMPS (30 microM), a specific antagonist of protein kinase A. This suggests that mGluRs localized at the soma-dendritic level of GABAergic interneurons and positively coupled to cyclic AMP may modulate GABA release during a critical period of postnatal development.

Intra-Task Reliability and Specificity of Individual Consistency

1970 ◽  
Vol 30 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Albert V. Carron
Keyword(s):  
Motor Response ◽  
Present Report ◽  
Motor Task ◽  
Response Component ◽  
Linear Movement ◽  
The Mean ◽  
Individual Consistency ◽  
Response Consistency ◽  
Relationship Of ◽  
The Relationship

The present report is based on reanalysis of data of Marisi (1969) in order to examine the relationship of consistency of motor response among the component responses of a single motor task. 120 high school Ss were tested on a special task, the rho. A single trial on this motor task can be logically separated into three component motor responses: reaction time, a short circular movement, and a short linear movement. The results indicated that consistency of motor response was moderately reliable within the response components but tended to be response-component specific. Further, both the reliability and specificity of motor-response consistency were independent of the size of the mean performance scores.

35Cl NQR Spectroscopy on Salts and Molecular Compounds of Trichloroacetic Acid

1986 ◽  
Vol 41 (1-2) ◽  
pp. 215-224 ◽  
Author(s):  
Winfried Fichtner ◽  
Axel Markworth ◽  
Norbert Weiden ◽  
Alarich Weiss
Keyword(s):  
Frequency Shift ◽  
Temperature Dependence ◽  
Linear Relation ◽  
Trichloroacetic Acid ◽  
Mean Frequency ◽  
35Cl Nqr ◽  
The Mean ◽  
Molecular Compounds

The temperature dependence of salts M(1)H(Cl3CCOO)2 and molecular compounds of trichloroacetic acid with amines and benzaldehydes, TCA · X, was studied,The data fit rather well to the known dependence of the mean frequency shift Δ <v(35Cl)> on the pkadifference of X with respect to TCA. A linear relation is observed between the bleaching out temperature Tb of the 35Cl NQR lines and Δ <v(35Cl)> for M(1)H(Cl3CCOO)2 and for TCA · X, X = benzaldehydes.

scholarly journals Demand on skillfulness modulates interhemispheric inhibition of motor cortices

2016 ◽  
Vol 115 (6) ◽  
pp. 2803-2813 ◽  
Author(s):  
Miles Wischnewski ◽  
Greg M. Kowalski ◽  
Farrah Rink ◽  
Samir R. Belagaje ◽  
Marc W. Haut ◽  
...  
Keyword(s):  
Primary Motor Cortex ◽  
Motor Task ◽  
Conditioning Stimulus ◽  
Motor Evoked Potential ◽  
Inhibitory Effect ◽  
Left Hand ◽  
The Mean ◽  
Small Targets ◽  
Healthy Participants

The role of primary motor cortex (M1) in the control of hand movements is still unclear. Functional magnetic resonance imaging (fMRI) studies of unimanual performance reported a relationship between level of precision of a motor task and additional ipsilateral M1 (iM1) activation. In the present study, we determined whether the demand on accuracy of a movement influences the magnitude of the inhibitory effect between primary motor cortices (IHI). We used transcranial magnetic stimulation (TMS) to measure active IHI (aIHI) of the iM1 on the contralateral M1 (cM1) in the premovement period of a left-hand motor task. Ten healthy participants manipulated a joystick to point to targets of two different sizes. For aIHI, the conditioning stimulus (CS) was applied to iM1, and the test stimulus (TS) to cM1, with an interstimulus interval of 10 ms. The amount of the inhibitory effect of the CS on the motor-evoked potential (MEP) of the subsequent TS was expressed as percentage of the mean MEP amplitude evoked by the single TS. Across different time points of aIHI measurements in the premovement period, there was a significant effect for target size on aIHI. Preparing to point to small targets was associated with weaker aIHI compared with pointing to large targets. The present findings suggest that, during the premovement period, aIHI from iM1 on cM1 is modulated by the demand on accuracy of the motor task. This is consistent with task fMRI findings showing bilateral M1 activation during high-precision movements but only unilateral M1 activity during low-precision movements.

scholarly journals Improving peripherally inserted central catheter appropriateness and reducing device-related complications: a quasiexperimental study in 52 Michigan hospitals

2021 ◽  
pp. bmjqs-2021-013015
Author(s):  
Vineet Chopra ◽  
Megan O'Malley ◽  
Jennifer Horowitz ◽  
Qisu Zhang ◽  
Elizabeth McLaughlin ◽  
...  
Keyword(s):  
Central Line ◽  
Hospital Performance ◽  
Policy Implications ◽  
Change Point Analysis ◽  
Absolute Difference ◽  
Peripherally Inserted Central Catheter ◽  
Central Catheter ◽  
Appropriateness Criteria ◽  
Mean Frequency ◽  
The Mean

BackgroundThe Michigan Appropriateness Guide for Intravenous Catheters (MAGIC) provides evidence-based criteria for peripherally inserted central catheter (PICC) use. Whether implementing MAGIC improves PICC appropriateness and reduces complications is unknown.MethodsA quasiexperimental study design to implement MAGIC in 52 Michigan hospitals was used. Data were collected from medical records by trained abstractors. Hospital performance on three appropriateness criteria was measured: short-term PICC use (≤5 days), use of multilumen PICCs and PICC placement in patients with chronic kidney disease. PICC appropriateness and device complications preintervention (January 2013 to December 2016) versus postintervention (January 2017 to January 2020) were compared. Change-point analysis was used to evaluate the effect of the intervention on device appropriateness. Logistic regression and Poisson models were fit to assess the association between appropriateness and complications (composite of catheter occlusion, venous thromboembolism (VTE) and central line-associated bloodstream infection (CLABSI)).ResultsAmong 38 592 PICCs, median catheter dwell ranged from 8 to 56 days. During the preintervention period, the mean frequency of appropriate PICC use was 31.9% and the mean frequency of complications was 14.7%. Following the intervention, PICC appropriateness increased to 49.0% (absolute difference 17.1%, p<0.001) while complications decreased to 10.7% (absolute difference 4.0%, p=0.001). Compared with patients with inappropriate PICC placement, appropriate PICC use was associated with a significantly lower odds of complications (OR 0.29, 95% CI 0.25 to 0.34), including decreases in occlusion (OR 0.25, 95% CI 0.21 to 0.29), CLABSI (OR 0.61, 95% CI 0.46 to 0.81) and VTE (OR 0.40, 95% CI 0.33 to 0.47, all p<0.01). Patients with appropriate PICC placement had lower rate of complications than those with inappropriate PICC use (incidence rate ratio 0.987, 95% CI 0.98 to 0.99, p<0.001).ConclusionsImplementation of MAGIC in Michigan hospitals was associated with improved PICC appropriateness and fewer complications. These findings have important quality, safety and policy implications for hospitals, patients and payors.

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