scholarly journals Video Camera Analysis to Capture Muscle Specific Endurance

2021 ◽  
Vol 9 (4) ◽  
Author(s):  
Olivia Hooks ◽  
Kevin McCully
Keyword(s):  
Confidence Interval ◽  
Healthy Subjects ◽  
Video Camera ◽  
Muscle Endurance ◽  
Triaxial Accelerometer ◽  
Endurance Test ◽  
Resultant Vector ◽  
Video Images ◽  
Hamstring Muscles ◽  
The Mean

Previous studies have used an accelerometer to evaluate muscle endurance. This study compared endurance index values using a video phone to an accelerometer. Eleven healthy subjects (19-22yrs) were electrically stimulated for 5 minutes at 5 Hz on the hamstring muscles. Four 10s videos were captured at 1080p and 60fps (~283,000 pixels) with the phone. Videos were analyzed using sequential correlations (consecutive 1-2, or consecutive skipping an image 1–3) of the video images between the electrodes. The magnitude of the decrease in the correlation was used to indicate movement. A triaxial accelerometer measured the resultant vector of the movements and the decrease in acceleration was used to indicate fatigue. Analysis using 1-3 produced higher delta R2 values compared to 1-2 (0.038+0.004; 0.020+0.001). Endurance index was 72.1+19.4% for the accelerometer and 71.1+18.6% for the phone images, p=0.64. The mean difference between the methods was not different from zero and the 90% confidence interval was within 5%. In conclusion, the consecutive correlations method detected decreases in movement due to fatigue. The video method provided equivalent values to the previously established accelerometer method to measure muscle endurance. These results support the use of video to assess muscle acceleration during muscle specific endurance test.

scholarly journals Endurance of the Dorsal and Ventral Muscles in the Neck

2020 ◽  
Vol 5 (3) ◽  
pp. 47
Author(s):  
Cameron M. Liss ◽  
Adeola A. Sanni ◽  
Kevin K. McCully
Keyword(s):  
Skeletal Muscle ◽  
Healthy Subjects ◽  
Vastus Lateralis ◽  
Random Order ◽  
Muscle Endurance ◽  
Triaxial Accelerometer ◽  
Head Impacts ◽  
Resultant Vector ◽  
Upper Trapezius ◽  
Maximal Acceleration

Endurance of the muscles of the neck are rarely studied. This study measured the endurance index (EI) of the sternocleidomastoid (SCM) and upper trapezius muscles of the neck (trap). The vastus lateralis (VL) was used for comparison. Skeletal muscle endurance of twelve healthy subjects, age 19–22 years, were tested on their SCM and trap in random order on one day, VL was tested on a separate day. Participants were tested in the supine position for the SCM and VL muscles and the prone position for the trap. Muscle contractions consisted of a 5 Hz twitch electrical stimulation for 5 min. Muscle acceleration (resultant vector) was measured using a triaxial accelerometer. EI was the ending acceleration as a percentage of the maximal acceleration. The endurance index (EI) for the SCM, trap, and VL was 42.3 ± 13.0%, 42.3 ± 20.2%, and 92.9 ± 11.0%, respectively. The EI of the VL was significantly higher than the EI of the SCM (t(2,22) = 10.33, p < 0.001) and the trap (t(2,22) = 7.625, p < 0.001). The EI was not different between the SCM and the trap muscle (t(2,22) = 0.004, p = 0.997). In conclusion, the neck muscles had much less endurance than the muscles in the leg and could make fatigued athletes more susceptible to concussions caused by head impacts.

STATIC ENDURANCE OF THE BACK EXTENSOR MUSCLES: ASSOCIATION BETWEEN PERFORMANCE AND REPORTED REASONS FOR TEST TERMINATION

2010 ◽  
Vol 13 (01) ◽  
pp. 13-21 ◽  
Author(s):  
Chidozie E. Mbada ◽  
Olusola Ayanniyi ◽  
Rufus A. Adedoyin ◽  
Olubusola E. Johnson
Keyword(s):  
Endurance Performance ◽  
Low Back ◽  
Endurance Test ◽  
Chi Square ◽  
Endurance Time ◽  
Hamstring Muscles ◽  
Extensor Muscles ◽  
The Mean ◽  
Α Level ◽  
Back Extensor

Purpose: Quite a few studies have reported previously on reasons for terminating tests of back muscles endurance. This study investigated the association between endurance performance and reported reasons for terminating back extensor muscle endurance test in apparently healthy adults. Methods: Three-hundred-and-seventy-six volunteers with the mean age of 38.9 ± 13.5 years participated in this study. All participants underwent modified Biering–Sørensen test of Static Muscular Endurance. Descriptive statistics of mean and standard deviation, Pearson's correlation and Chi-square, ANOVA and ANCOVA were used to analyze the data. The α level was set at 0.05. Results: It is found that 76.1% of the participants terminated the test due to fatigue in the low back, followed by low-back pain (LBP) (12.8%) and fatigue in the gluteal or hamstring muscles (7.4%) respectively. The magnitudes of the endurance time for each reason of termination — fatigue in the low back (121 ± 49.3 sec), fatigue in the gluteal or hamstring muscles (102 ± 44.0 sec), LBP (59 ± 27.4 sec), and behavioral factors (92 ± 34.7 sec) were found to be significantly different (p = 0.001). Test termination due to fatigue in the low back was on the average 62 seconds longer than that due to LBP. Conclusions: Fatigue was the most commonly reported reason for back extensor muscles' endurance test termination. Endurance time was least in those individuals who terminate the test due to complaints of LBP and greatest in those who end the task for fatigue only.

scholarly journals In situ target strength estimates of visually verified orange roughy

2012 ◽  
Vol 70 (1) ◽  
pp. 215-222 ◽  
Author(s):  
Gavin J. Macaulay ◽  
Rudy J. Kloser ◽  
Tim E. Ryan
Keyword(s):  
Confidence Interval ◽  
Video Camera ◽  
Target Strength ◽  
Orange Roughy ◽  
Camera System ◽  
The Mean ◽  
Intractable Problem ◽  
Video Camera System ◽  
Fish Avoidance

Abstract Macaulay, G. J., Kloser, R. J., and Ryan, T. E. 2013. In situ target strength estimates of visually verified orange roughy. – ICES Journal of Marine Science, 70:215–222. The first estimates of orange roughy (Hoplostethus atlanticus) target strength at 38 and 120 kHz with visual verification were obtained from a self-contained echosounder and video camera system affixed to a demersal trawl towed through dense aggregations of spawning orange roughy. Mean target strength estimates were obtained from 24 tracks of orange roughy containing 83 echoes. The mean target strength at 38 kHz was –52.0 dB with a 95% confidence interval of –53.3 to –50.9 dB for fish with a mean length of 33.9 cm. At 120 kHz the mean target strength was –47.9 dB (confidence interval of –48.8 to –46.4 dB). This work makes two significant advances: in situ TS measurements have been made that can be confidently attributed to orange roughy, and using a trawl to herd orange roughy past the system resolved the previously intractable problem of fish avoidance.

Video Digitizing Analysis System

1987 ◽  
Vol 3 (1) ◽  
pp. 80-86 ◽  
Author(s):  
Robert Shapiro ◽  
Chris Blow ◽  
Greg Rash
Keyword(s):  
Video Camera ◽  
Basic Program ◽  
Video Image ◽  
Live Video ◽  
Video Images ◽  
The Mean ◽  
The Cross ◽  
Analysis System ◽  
Set Of Points ◽  
Ibm Pc

The use of video images in biomechanical analyses has become more realistic since the introduction of the shuttered video camera. Although recording rates are still limited to 60 Hz, exposure times can be reduced to prevent blurring in most situations. This paper presents a system for manually digitizing video images, a system that utilizes a video overlay board to place a set of cross hairs directly on a previously recorded or live video image. A cursor is used to move the cross hairs over required points. A BASIC program was written for a IBM PC-AT computer to accomplish this task. Video images of a known set of points were digitized, and calculated distances between points were compared to real distances. The mean of the observed errors was 0.79%. It was concluded that this digitizing system, within the limitations of video resolution, yielded digitizing errors similar in magnitude to those observed in cinematographic analyses.

Ratio imaging of intracellular ion concentration

1992 ◽  
Vol 50 (2) ◽  
pp. 1160-1161
Author(s):  
Stephen R. Bolsover
Keyword(s):  
Individual Cell ◽  
Video Camera ◽  
Field Of View ◽  
Ion Concentration ◽  
Fluorescence Signal ◽  
Ion Imaging ◽  
Ratiometric Fluorescence ◽  
Ratio Imaging ◽  
The Mean ◽  
The Many

The field of intracellular ion concentration measurement expanded greatly in the 1980's due primarily to the development by Roger Tsien of ratiometric fluorescence dyes. These dyes have many applications, and in particular they make possible to image ion concentrations: to produce maps of the ion concentration within living cells. Ion imagers comprise a fluorescence microscope, an imaging light detector such as a video camera, and a computer system to process the fluorescence signal and display the map of ion concentration.Ion imaging can be used for two distinct purposes. In the first, the imager looks at a field of cells, measuring the mean ion concentration in each cell of the many in the field of view. One can then, for instance, challenge the cells with an agonist and examine the response of each individual cell. Ion imagers are not necessary for this sort of experiment: one can instead use a system that measures the mean ion concentration in a just one cell at any one time. However, they are very much more convenient.

METHODOLOGICAL STUDY OF THE RADIOIMMUNOASSAY OF HUMAN THYROTROPHIN

1972 ◽  
Vol 71 (1) ◽  
pp. 24-36 ◽  
Author(s):  
Ariel Gordin ◽  
Pirkko Saarinen
Keyword(s):  
Healthy Subjects ◽  
Binding Capacity ◽  
Paper Electrophoresis ◽  
Storage Conditions ◽  
Methodological Study ◽  
Double Antibody ◽  
The Mean ◽  
Specific Activities ◽  
Initial Binding ◽  
In Pregnancy

ABSTRACT An account is given of a methodological study of the double-antibody radioimmunoassay of human TSH, using highly purified labelled human TSH as tracer. It was shown that conventional paper electrophoresis was not adequate for studying the purity of labelled human TSH. When polyvinylchloride (Pevikon®) electrophoresis was used, four subfractions could still be separated, even though, on paper electrophoresis, the material seemed to be homogeneous. Only two of the four Pevikon fractions were immunoreactive. Purification of labelled human TSH by Pevikon electrophoresis also improved the sensitivity of the assay. Specific activities of about 100 mCi/mg gave the highest initial binding capacity, produced least damage to the labelled hormone and showed the best stability of the tracer without influencing the sensitivity of the method. In different storage conditions, labelled human TSH was found to be most stable at −20°C and diluted 1/100. Only in pregnancy did the addition of HCG seem necessary. The mean TSH value in healthy subjects was 3.6 ± 1.4 μU/ml (mean±sd) with a range from 1.6 μU/ml to 8.8 μU/ml.

The Y-shaped trabecular bone structure in the odontoid process of the axis: a CT scan study in 54 healthy subjects and biomechanical considerations

2019 ◽  
Vol 30 (5) ◽  
pp. 585-592 ◽  
Author(s):  
Nicola Montemurro ◽  
Paolo Perrini ◽  
Vittoriano Mangini ◽  
Massimo Galli ◽  
Andrea Papini
Keyword(s):  
Ct Scan ◽  
Healthy Subjects ◽  
Bone Structure ◽  
Cone Beam Ct ◽  
Odontoid Process ◽  
Trabecular Structure ◽  
Anatomical Entity ◽  
Significant Difference ◽  
Axial Ct ◽  
The Mean

OBJECTIVEOdontoid process fractures are very common in both young and geriatric patients. The axial trabecular architecture of the dens appears to be crucial for physiological and biomechanical function of the C1–2 joint. The aim of this study is to demonstrate the presence of a Y-shaped trabecular structure of the dens on axial CT and to describe its anatomical and biomechanical implications.METHODSFifty-four C2 odontoid processes in healthy subjects were prospectively examined for the presence of a Y-shaped trabecular structure at the odontocentral synchondrosis level with a dental cone beam CT scan. Length, width, and axial area of the odontoid process were measured in all subjects. In addition, measurements of the one-third right anterior area of the Y-shaped structure were taken.RESULTSThe Y-shaped trabecular structure was found in 79.6% of cases. Length and width of the odontoid process were 13.5 ± 0.6 mm and 11.2 ± 0.9 mm, respectively. The mean area of the odontoid process at the odontocentral synchondrosis was 93.5 ± 4.3 mm2, whereas the mean one-third right anterior area of the odontoid process at the same level was 29.3 ± 2.5 mm2. The mean area of the odontoid process and its length and width were similar in men and women (p > 0.05). No significant difference was found in the mean area of the odontoid process in people older than 65 years (94 ± 4.2 mm2) compared to people younger than 65 years (93.3 ± 4.4 mm2; p > 0.05).CONCLUSIONSThe authors identified a new anatomical entity, named the Y-shaped trabecular structure of the odontoid process, on axial CT scans. This structure appears to be the result of bone transformation induced by the elevated dynamic loading at the C1–2 level. The presence of the Y-shaped structure provides new insights into biomechanical responses of C2 under physiological loading and traumatic conditions.

Association of Serum Homocysteine Level and Interstitial Lung Disease in Systemic Sclerosis: A Case-control Study

2018 ◽  
Vol 15 (1) ◽  
pp. 74-78
Author(s):  
Mohammadali Nazarinia ◽  
Asghar Zare ◽  
Mohammad javad Fallahi ◽  
Mesbah Shams
Keyword(s):  
Systemic Sclerosis ◽  
Healthy Subjects ◽  
Case Control Study ◽  
Homocysteine Level ◽  
Case Control ◽  
Control Group ◽  
Lung Involvement ◽  
Serum Homocysteine ◽  
The Mean ◽  
Control Study

Background:Systemic sclerosis is a disorder of connective tissue with unknown cause, affecting the skin and internal organs, characterized by fibrotic changes.Objective:To determine the correlation between serum homocysteine level and interstitial lung involvement in systemic sclerosis. </P><P> Materials and Methods: In this case – control study, 59 patients who fulfilled the ACR/EULAR classification criteria for systemic sclerosis and were referred to Hafez Hospital of Shiraz, Iran, were included as the case group. Fifty nine healthy subjects were involved as the control group. Patients were divided into two groups based on interstitial lung involvement and two subtypes, diffuse and limited type. Serum homocysteine, vitamin B12, and folate levels compared between the controls, and cases groups.Results:Of 59 case and control group, 53 (%89.8) were female and the mean age did not differ in both groups (P=0.929). Thirty five (%59.3) patients had interstitial lung involvement and 38(%64.4) had diffuse cutaneous systemic sclerosis. The mean serum homocysteine level was 13.9±6.3 µmol/L in the case and 13.7±9.2 µmol/L in the control group (P=0.86). The mean serum homocysteine level did not differ between the patients with and without interstitial lung involvement (P=0.52). The patients with lung involvement was older than those without lung involvement (P=0.004). Lung disease was more common in diffuse type (P=0.014).Conclusion:In our study, serum homocysteine level did not differ between the patients and healthy subjects. Also, there was no correlation between serum homocysteine level and lung involvement, but lung involvement was more common in older patients and also diffuse subtype.

scholarly journals Onchocerciasis control in Ghana (1974–2016)

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nana-Kwadwo Biritwum ◽  
Dziedzom K. de Souza ◽  
Odame Asiedu ◽  
Benjamin Marfo ◽  
Uche Veronica Amazigo ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Vector Control ◽  
Control Strategy ◽  
Financial Support ◽  
Control Programme ◽  
Ivermectin Treatment ◽  
Mobile Community ◽  
The Mean ◽  
The Impact ◽  
Onchocerciasis Control

Abstract Background The control of onchocerciasis in Ghana started in 1974 under the auspices of the Onchocerciasis Control Programme (OCP). Between 1974 and 2002, a combination of approaches including vector control, mobile community ivermectin treatment, and community-directed treatment with ivermectin (CDTI) were employed. From 1997, CDTI became the main control strategy employed by the Ghana OCP (GOCP). This review was undertaken to assess the impact of the control interventions on onchocerciasis in Ghana between 1974 and 2016, since which time the focus has changed from control to elimination. Methods In this paper, we review programme data from 1974 to 2016 to assess the impact of control activities on prevalence indicators of onchocerciasis. This review includes an evaluation of CDTI implementation, microfilaria (Mf) prevalence assessments and rapid epidemiological mapping of onchocerciasis results. Results This review indicates that the control of onchocerciasis in Ghana has been very successful, with a significant decrease in the prevalence of infection from 69.13% [95% confidence interval) CI 60.24–78.01] in 1975 to 0.72% (95% CI 0.19–1.26) in 2015. Similarly, the mean community Mf load decreased from 14.48 MF/skin snip in 1975 to 0.07 MF/skin snip (95% CI 0.00–0.19) in 2015. Between 1997 and 2016, the therapeutic coverage increased from 58.50 to 83.80%, with nearly 100 million ivermectin tablets distributed. Conclusions Despite the significant reduction in the prevalence of onchocerciasis in Ghana, there are still communities with MF prevalence above 1%. As the focus of the GOCP has changed from the control of onchocerciasis to its elimination, both guidance and financial support are required to ensure that the latter goal is met.

scholarly journals Can Health-Promoting Schools Contribute to Better Health Behaviors? Physical Activity, Sedentary Behavior, and Dietary Habits among Israeli Adolescents

2021 ◽  
Vol 18 (3) ◽  
pp. 1183
Author(s):  
Hila Beck ◽  
Riki Tesler ◽  
Sharon Barak ◽  
Daniel Sender Moran ◽  
Adilson Marques ◽  
...  
Keyword(s):  
Physical Activity ◽  
Health Behavior ◽  
Confidence Interval ◽  
Health Behaviors ◽  
Sedentary Behavior ◽  
Dietary Habits ◽  
Group Differences ◽  
Time Behavior ◽  
Health Promoting ◽  
The Mean

Schools with health-promoting school (HPS) frameworks are actively committed to enhancing healthy lifestyles. This study explored the contribution of school participation in HPS on students’ health behaviors, namely, physical activity (PA), sedentary behavior, and dieting. Data from the 2018/2019 Health Behavior in School-aged Children study on Israeli adolescents aged 11–17 years were used. Schools were selected from a sample of HPSs and non-HPSs. Between-group differences and predictions of health behavior were analyzed. No between-group differences were observed in mean number of days/week with at least 60 min of PA (HPS: 3.84 ± 2.19 days/week, 95% confidence interval of the mean = 3.02–3.34; non-HPS: 3.93 ± 2.17 days/week, 95% confidence interval of the mean = 3.13–3.38). Most children engaged in screen time behavior for >2 h/day (HPS: 60.83%; non-HPS: 63.91%). The odds of being on a diet were higher among more active children (odds ratio [OR] = 1.20), higher socio-economic status (OR = 1.23), and female (OR = 2.29). HPS did not predict any health behavior. These findings suggest that HPSs did not contribute to health behaviors more than non-HPSs. Therefore, health-promoting activities in HPSs need to be improved in order to justify their recognition as members of the HPS network and to fulfill their mission.

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