scholarly journals Assessment of nanoindentation in stiffness measurement of soft biomaterials: kidney, liver, spleen and uterus

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guanlin Wu ◽  
Michael Gotthardt ◽  
Maik Gollasch
Keyword(s):  
Mechanical Properties ◽  
Ex Vivo ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Biological Specimen ◽  
Good Reliability ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Kidney Liver ◽  
Soft Biomaterials

Abstract Nanoindentation technology with high spatial resolution and force sensitivity is widely used to measure the mechanical properties of hard biomaterials and tissues. However, its reliability to analyze soft biomaterials and organs has not been tested. Here, we evaluated the utility of nanoindentation to measure the passive mechanical properties of soft biological specimen. Kidney, liver, spleen and uterus samples were harvested from C57BL/6 N mice. We assessed test–retest repeatability in biological specimen and hydrogel controls using Bland–Altman diagrams, intraclass correlation coefficients (ICCs) and the within-subject coefficients of variation (COVs). The results were calculated using Hertzian, JKR and Oliver & Pharr models. Similar to hydrogels, Bland–Altman plots of all biological specimen showed good reliability in stiffness test and retest examinations. In gels, ICCs were larger than 0.8 and COVs were smaller than 15% in all three models. In kidney, liver, spleen and uterus, ICCs were consistently larger than 0.8 only in the Hertzian model but not in the JKR and Oliver & Pharr models. Similarly, COVs were consistently smaller than 15% in kidney, liver, spleen and uterus only in the Hertzian model but not in the other models. We conclude that nanoindentation technology is feasible in detecting the stiffness of kidney, liver, spleen and uterus. The Hertzian model is the preferred method to provide reliable results on ex vivo organ stiffness of the biological specimen under study.

scholarly journals Action Boundary Proximity Effects on Perceptual-Motor Judgments

2019 ◽  
Vol 90 (12) ◽  
pp. 1000-1008
Author(s):  
Caleb D. Johnson ◽  
Alice D. LaGoy ◽  
Gert-Jan Pepping ◽  
Shawn R. Eagle ◽  
Anne Z. Beethe ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Reaction Times ◽  
Correlation Coefficients ◽  
Proximity Effects ◽  
Testing Time ◽  
Good Reliability ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Time Required ◽  
Action Coupling

INTRODUCTION: Designed as a more ecological measure of reaction times, the Perception-Action Coupling Task (PACT) has shown good reliability and within-subject stability. However, a lengthy testing period was required. Perceptual-motor judgments are known to be affected by proximity of the stimulus to the action boundary. The current study sought to determine the effects of action boundary proximity on PACT performance, and whether redundant levels of stimuli, eliciting similar responses, can be eliminated to shorten the PACT.METHODS: There were 9 men and 7 women who completed 4 testing sessions, consisting of 3 familiarization cycles and 6 testing cycles of the PACT. For the PACT, subjects made judgments on whether a series of balls presented on a tablet afford “posting” (can fit) through a series of apertures. There were 8 ratios of ball to aperture size (B-AR) presented, ranging from 0.2 to 1.8, with each ratio appearing 12 times (12 trials) per cycle. Reaction times and judgment accuracy were calculated, and averaged across all B-ARs. Ratios and individual trials within each B-AR were systematically eliminated. Variables were re-averaged, and intraclass correlation coefficients (ICC) and coefficients of variation (CVTE) were calculated in an iterative manner.RESULTS: With elimination of the 0.2 and 1.8 B-ARs, the PACT showed good reliability (ICC = 0.81–0.99) and consistent within-subject stability (CVTE = 2.2–14.7%). Reliability (ICC = 0.81–0.97) and stability (CVTE = 2.6–15.6%) were unaffected with elimination of up to 8 trials from each B-AR.DISCUSSION: The shortened PACT resulted in an almost 50% reduction in total familiarization/testing time required, significantly increasing usability.Johnson CD, LaGoy AD, Pepping G-J, Eagle SR, Beethe AZ, Bower JL, Alfano CA, Simpson RJ, Connaboy C. Action boundary proximity effects on perceptual-motor judgments. Aerosp Med Hum Perform. 2019; 90(12):1000–1008.

Reproducibility of 24-h energy expenditure and macronutrient oxidation rates in an indirect calorimeter

1996 ◽  
Vol 80 (1) ◽  
pp. 133-139 ◽  
Author(s):  
M. D. White ◽  
G. Bouchard ◽  
B. Buemann ◽  
N. Almeras ◽  
J. P. Despres ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Whole Body ◽  
Tissue Mass ◽  
Intraclass Correlation Coefficients ◽  
Oxidation Rates ◽  
Coefficients Of Variation ◽  
Habitual Diet ◽  
Adipose Tissue Mass

The maintenance of weight and adipose tissue mass in humans appears to be related to a balance between the rates of oxidation and consumption of macronutrients; yet, little evidence is available on the reproducibility of 24-h macronutrient oxidation rates and how this relates to diet in the days preceding a chamber session. This study examined the reproducibility of 24-h macronutrient oxidation rates, 24-h energy expenditure (EE), and respiratory quotient (RQ) in 30 adults who ate their habitual diets before two 24-h whole body indirect calorimeter sessions. Results showed that the within-subject coefficients of variation (CVws) for 24-h EE and RQ were 2.8 and 2.6%, respectively. CVws for macronutrient oxidations ranged from approximately 15 to 25%. Means comparisons of 24-h EE, RQ, and macronutrient oxidation rates between sessions showed no significant differences, and all variables had significant positive intraclass correlation coefficients (P < 0.05). In conclusion, macronutrient oxidations all showed significant reproducibility for the group and a significant but lower reproducibility for individuals when habitual diet and activity preceded the experimental sessions.

Reproducibility of Acoustic Rhinometry in the Investigation of Occupational Rhinitis

2007 ◽  
Vol 21 (4) ◽  
pp. 474-477 ◽  
Author(s):  
Roberto Castano ◽  
Gilles Thériault ◽  
Denyse Gautrin ◽  
Heberto Ghezzo ◽  
Carole Trudeau ◽  
...  
Keyword(s):  
Objective Assessment ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Acoustic Rhinometry ◽  
Nasal Patency ◽  
Cross Sectional ◽  
Occupational Rhinitis ◽  
Intraclass Correlation Coefficients ◽  
Objective Monitoring ◽  
Coefficients Of Variation

Background To diagnose occupational rhinitis, it is mandatory to conduct an objective assessment of changes in nasal patency during specific inhalation challenge (SIC). The reproducibility of acoustic rhinometry measurements in the setting of occupational challenges has never been examined. This study assessed the reproducibility of acoustic rhinometry during SIC investigation of occupational rhinitis. Methods Twenty-four subjects underwent acoustic rhinometry measurements during SIC investigation of occupational rhinitis. Subjects attended 3–6 days of SIC within a week by means of a realistic or closed-circuit apparatus methodology Results All of the within-day intraclass correlation coefficients (ICCs) for nasal volume (2–5 cm) and minimum cross-sectional area (MCA) based on a different number of measurements (2–7) were above 0.85; all of the coefficients of variation (CVs) for the same parameters were low (below 10%). The between-day CVs based on different numbers of SIC sessions ranged from 8.0 to 8.8% and from 6.8 to 8.8% for nasal volume and MCA, respectively. The between-day ICCs ranged from 0.80 to 0.88 and from 0.83 to 0.94 for nasal volume and MCA, respectively. Conclusion Acoustic rhinometry showed good within- and between-day reproducibility and can be recommended for the objective monitoring of nasal patency during SIC investigating occupational rhinitis.

Reliability of Dermatologists in Acne Lesion Counts and Global Assessments

2006 ◽  
Vol 10 (4) ◽  
pp. 160-165 ◽  
Author(s):  
Jerry K.L. Tan ◽  
Karen Fung ◽  
Lynne Bulger
Keyword(s):  
Intraclass Correlation ◽  
Training Session ◽  
Correlation Coefficients ◽  
Good Reliability ◽  
Inflammatory Lesions ◽  
Acne Lesion ◽  
Intraclass Correlation Coefficients ◽  
Outcome Measurements ◽  
Group A ◽  
Group B

Background: There is a paucity of data on the reliability of dermatologists in acne lesion counting and global severity assessments. The effects of training and practice on reliability are also uncertain. The objective of this study was to determine the reliability of these outcome measurements when performed by trained dermatologists. Methods: Eleven dermatologists were divided into two groups that evaluated the same six acne subjects twice on the same day. A training session was provided either after (group A) or before (group B) the first patient evaluation sessions. Reliability of raters in lesion counting and global severity assessment was determined by calculation of intraclass correlation coefficients (ICCs). ICC values close to 1.0 indicate excellent reliability, whereas values less than 0.75 are considered unacceptable. Results: Intrarater ICCs ranged from 0.37 to 0.99 for noninflammatory lesions, 0.26 to 0.97 for inflammatory lesions, and 0.56 to 0.83 for global assessments for group A (trained after); corresponding values for group B (trained before) were 0.84 to 0.98, 0.61 to 0.95, and 0.43 to 0.91. ICC values ≥ 0.75 for all three outcome parameters were observed in one of six group A and three of five group B raters. Interrater ICCs for groups A and B after the first evaluation session were 0.17 versus 0.68 for noninflammatory counts, 0.84 versus 0.72 for inflammatory counts, and 0.71 versus 0.65 for global assessments, respectively. Corresponding values after session 2 were 0.79 and 0.77 for noninflammatory, 0.81 and 0.90 for inflammatory, and 0.61 and 0.77 for global assessments. Conclusion: Dermatologists tended to be reliable in acne lesion counting but somewhat less so in global assessments. Training tended to improve group reliability in noninflammatory lesion counts and increased the proportion of raters with good reliability in all three outcome measures. Practice enhanced reliability in all outcome measurements.

Reliability of Clinical Tests of Foot and Ankle Characteristics in Older People

2003 ◽  
Vol 93 (5) ◽  
pp. 380-387 ◽  
Author(s):  
Hylton B. Menz ◽  
Anne Tiedemann ◽  
Marcella Mun-San Kwan ◽  
Mark Dominic Latt ◽  
Catherine Sherrington ◽  
...  
Keyword(s):  
Older People ◽  
Hallux Valgus ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Foot And Ankle ◽  
Clinical Tests ◽  
First Metatarsophalangeal Joint ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Severity Grading

Lower-extremity problems are common in older people; however, the reliability of clinical tools used to assess foot and ankle characteristics has not been rigorously evaluated. This study evaluated the test–retest reliability of a battery of simple clinical tests of foot and ankle characteristics (tactile sensitivity of the first metatarsophalangeal joint, navicular height, foot length and width, hallux valgus severity, an overall foot problem score, ankle flexibility, ankle dorsiflexion strength, and foot pain) in 31 individuals (13 men and 18 women) aged 76 to 87 years recruited from the community. Three examiners performed the tests on two occasions approximately 2 weeks apart. Intraclass correlation coefficients and coefficients of variation were calculated for continuously scored tests, and the kappa statistic (κ) was used to determine the reliability of hallux valgus severity grading. All of the continuously scored tests had acceptable reliability (intraclass correlation coefficients of 0.64 to 0.98; coefficients of variation of 0.6% to 15.0%), as did hallux valgus severity grading (κ = 0.77; absolute percentage agreement, 84%). These simple clinical tests can now be used with confidence in clinical and research settings to provide reliable and functionally important information regarding foot and ankle characteristics in older people. (J Am Podiatr Med Assoc 93(5): 380-387, 2003)

scholarly journals Development of a Fitness Test Battery for Special Weapons and Tactics (SWAT) Operators—A Pilot Study

2021 ◽  
Vol 18 (15) ◽  
pp. 7992
Author(s):  
Megan Sax van der Weyden ◽  
Christopher D. Black ◽  
Daniel Larson ◽  
Brian Rollberg ◽  
Jason A. Campbell
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Police Departments ◽  
Fitness Test ◽  
Intraclass Correlation Coefficients ◽  
Body Drag ◽  
Testing Measure ◽  
Coefficients Of Variation ◽  
Reliable Testing

This investigation examined relationships between a Special Weapons and Tactics-specific fitness test (SORT) and an obstacle course (OC) used for qualification in fourteen male SWAT members from three local, regional police departments. The SORT included: squat, pushup, and lunge in 60 s; pullup hold; sled drag; and Yo-Yo Intermittent Recovery Test L1. The obstacle course included: 25 m sprint (repeated); window ascent; scale under a wall; 25 m serpentine run (repeated), body drag (20 m, repeated). Pearson coefficients examined SORT and OC relationships (p ≤ 0.05); intraclass correlation coefficients (ICC2,1) assessed agreement of SORT trials. Repeated measures ANOVA evaluated differences in SORT metrics across time. Coefficients of variation (COV) examined SORT scoring consistency. The YoYo test was related to all SORT assessments (r = −0.803–0.894), except sled drag. The remaining SORT metrics were related to ≥two tests. SORT COVs ranged from 0.77–13.26% for trials 1–2 but decreased between trials 2–3 (0.95–8.97%). The OC was associated with YoYo, lunges, squats and sled drag (r = −0.790, −0.730, −0.766, and 0.802, respectively). No differences (p > 0.05) existed across SORT trials for event scores. The SORT battery appears to be a valid and reliable testing measure to assess SWAT occupational specific fitness.

scholarly journals Test–Retest Reliability of a New Device Versus a Long-Arm Goniometer to Evaluate Knee Proprioception

2021 ◽  
pp. 1-6
Author(s):  
Fei Tian ◽  
Yaqi Zhao ◽  
Jixin Li ◽  
Wenjin Wang ◽  
Danni Wu ◽  
...  
Keyword(s):  
Standard Error ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Joint Position Sense ◽  
Repeated Measurements ◽  
Good Reliability ◽  
Retest Reliability ◽  
New Device ◽  
Intraclass Correlation Coefficients ◽  
Test Retest Reliability

Context: Many methods used to evaluate knee proprioception have shortcomings that limit their use in clinical settings. Based on an inexpensive 3D camera, a new portable device was recently used to evaluate the joint position sense (JPS) of the knee joint. However, the test–retest reliability of the new method remains unclear. This study aimed to evaluate the test–retest reliability of the new device and a long-arm goniometer for assessing knee JPS, and to compare the variability of the 2 methods. Design: Prospective observational study of the test–retest reliability of knee JPS measurements. Methods: Twenty-one healthy adults were tested in 2 sessions with a 1-week interval. Three target knee flexion angles (30°, 45°, and 60°) were reproduced in each session. Target and reproduced angles were measured with both methods. Intraclass correlation coefficients, standard error of the measurement, and Bland–Altman plots were used to quantify test–retest reliability. Paired t tests were used to compare knee JPS (absolute error of the target-reproduced angle) between the methods. Results: The new device (good to excellent intraclass correlation coefficients .74–.80; standard error of the measurement 0.52°–0.61°) demonstrated better test–retest reliability than the goniometer (poor to fair intraclass correlation coefficients .23–.43; standard error of the measurement 0.89°–2.07°) and better test–retest agreement (respective mean differences for the 30°, 45°, and 60° knee angles: 0.11°, 0.13°, and 0.41° for the new system; 0.84°, 1.52°, and 1.18° for the goniometer). The measurements (absolute errors of the target-reproduced angles) with the goniometer were significantly greater than those with the new device (P < .05); the SDs of repeated measurements with the goniometer (1.50°–2.41°) were greater than with the new device (1.08°–1.38°). Conclusions: Given that the new device has good reliability and sufficient precision, it is the better alternative for evaluating knee JPS. Goniometers should be used with caution to assess knee JPS.

scholarly journals Acceleration of 2D-MR fingerprinting by reducing the number of echoes with increased in-plane resolution: a volunteer study

2020 ◽  
Vol 33 (6) ◽  
pp. 783-791
Author(s):  
Yusuke Yokota ◽  
Tomohisa Okada ◽  
Yasutaka Fushimi ◽  
Akira Yamamoto ◽  
Satoshi Nakajima ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Region Of Interest ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Volunteer Study ◽  
The Mean ◽  
T1 And T2 ◽  
High Repeatability ◽  
Measurement Repeatability

Abstract Objective To compare the absolute values and repeatability of magnetic resonance fingerprinting (MRF) with 3000 and 1500 echoes/slice acquired in 41 s and 20 s (MRF3k and MRF1.5k, respectively). Materials and methods MRF3k and MRF1.5k scans based on fast imaging with steady precession (FISP) were conducted using a 3 T scanner. Inter-scan agreement and intra-scan repeatability were investigated in 41 and 28 subjects, respectively. Region-of-interest (ROI) analysis was conducted on T1 values of MRF3k by two raters, and their agreement was evaluated using intraclass correlation coefficients (ICCs). Between MRF3k and MRF1.5k, differences in T1 and T2 values and inter-measurement correlation coefficients (CCs) were investigated. Intra-measurement repeatability was evaluated using coefficients of variation (CVs). A p value < 0.05 was considered statistically significant. Results The ICCs of ROI measurements were 0.77–0.96. Differences were observed between the two MRF scans, but the CCs of the overall ROIs were 0.99 and 0.97 for the T1 and T2 values, respectively. The mean and median CVs of repeatability were equal to or less than 1.58% and 3.13% in each of the ROIs for T1 and T2, respectively; there were some significant differences between MRF3k and MRF1.5k, but they were small, measuring less than 1%. Discussion Both MRF3k and MRF1.5k had high repeatability, and a strong to very strong correlation was observed, with a trend toward slightly higher values in MRF1.5k.

Assessment of Physical Activity in Adults: A Review of Validated Questionnaires From a Nutritionist’s Point of View

2020 ◽  
Vol 43 (4) ◽  
pp. 235-254
Author(s):  
Angela Patricia Bacelis-Rivero ◽  
Anabel Vázquez-Rodríguez ◽  
Claudia E. Carrasco-Legleu ◽  
Lidia G. De León ◽  
Sandra Alicia Reza-López
Keyword(s):  
Physical Activity ◽  
Energy Expenditure ◽  
Intraclass Correlation ◽  
Reliability And Validity ◽  
Correlation Coefficients ◽  
Epidemiological Studies ◽  
Point Of View ◽  
Eligibility Criteria ◽  
Good Reliability ◽  
Intraclass Correlation Coefficients

Physical activity (PA) is a component of total energy expenditure. PA and PA energy expenditure (PAEE) can be estimated by objective techniques (OTs). However, the use of questionnaires is frequent in clinical settings and epidemiological studies. We conducted a search on PubMed, Scopus, and Google Scholar databases to perform a review of studies reporting the reliability and validity of PA questionnaires validated against OTs—doubly labeled water (DLW) or accelerometers—in free-living adults. We selected original articles published between 2009 and 2019 that reported validation studies of PA questionnaires. We identified 53 studies that fulfilled the eligibility criteria. Four PA questionnaires were validated against DLW and the remaining against accelerometers. Three questionnaires were compared with both DLW and accelerometer results. The correlation between questionnaire-estimated PAEE and DLW results ranged from r = .22 to r = .46, while that between questionnaire-estimated total PA (TPA) and accelerometer results ranged from r = .11 to r = .54 The intraclass correlation coefficients were between .56 and .84. Despite having good reliability, most of the questionnaires included in this review have shown limited validity for estimating TPA in adults. OTs should be considered as a first option, when possible. Further research is warranted on techniques to obtain more accurate PA and PAEE estimates.

scholarly journals The 10/5 Repeated Jumps Test: Are 10 Repetitions and Three Trials Necessary?

Biomechanics ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 1-14
Author(s):  
Callum Stratford ◽  
Thomas Dos’Santos ◽  
John J. McMahon
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Force Plate ◽  
Correlation Coefficients ◽  
Pairwise Comparisons ◽  
Strength Index ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Repeated Measures Analysis ◽  
Ground Contact Time

The purpose of this study was to identify whether ten repetitions and three trials were necessary to achieve stability in peak reactive strength index (RSI) during the 10/5 repeated jumps test (RJT). Twenty-five males, from multiple sports, performed three trials of the RJT on an in-ground force plate, with 90 seconds’ rest between trials. Intraclass correlation coefficients (ICC = 0.916–0.986) and coefficients of variation (CV ≤ 14.5%) were considered acceptable for all variables. Repeated-measures analysis of variance and Freidman’s tests revealed large and significant differences (p ≤ 0.006, η2 = 0.159–0.434, power ≥ 0.859) in ground contact time (GCT), jump height (JH), and subsequently RSI both between trials and repetitions. Pairwise comparisons revealed that repetitions 1–3 produced longer GCTs (p ≤ 0.05, d = 0.41–1.40), lower JHs (p ≤ 0.05, d = 0.31–0.56), and lower RSI values (p ≤ 0.05, d = 0.35–1.24). The shortest GCTs, greatest JHs and greater RSIs occurred between repetitions 7 and 10, with approximately 60% of peak RSIs occurring during these ranges. The sequential estimate technique revealed that seven repetitions were needed to attain stability in mean peak RSI. Non-significant (p = 0.554) and negligible differences (d ≤ 0.09) in the five best RSIs between trials were noted. One trial of the 10/5 RJT is sufficient to evaluate peak RSI in athletes and should reduce data collection time and fatigue.

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