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Detrended fluctuation analysis (DFA) and sample entropy (SE) measure the long-term correlations and regularity of gait patterns, respectively, having previously been used to identify participants at risk of falling, previous history of injury, or patients with motor diseases. Since these measures are more sensitive to gait impairment than linear measures (e.g., the standard deviation [SD] of stride time), they can be potentially used in military medicine to identify soldiers at risk of injury. However, clinometric properties are yet to be established. What is the repeatability of DFA, SE, and traditional linear measures of stride time variability (SD and coefficient of variation [CV]) under various load and speed constraints? Fourteen Australian Army trainee soldiers (age: 25.6 ± 5.9 y, height: 1.74 ± 0.08 m, body mass: 77.2 ± 15.1 kg, service: 1.5 ± 1.8 y) attended three sessions over two weeks, completing four 12-minute walking trials on an instrumented treadmill in each session. Participants walked with a combination of 0 kg or 23 kg loads at a self-selected or 5.5 km/h speed. Heel contacts from the right foot were identified using treadmill-embedded force plates. From 512 stride time intervals, linear (SD and CV), and non-linear (DFA and SE) measures were obtained. To assess the between-session repeatability, intraclass correlations (ICC 2,1) were employed. There was poor-to-moderate repeatability for the SD (ICC: 0.357–0.545) and CV (ICC: 0.371–0.529). DFA showed poor-to-moderate repeatability (ICC: 0.013–0.504), while SE had poor repeatability (ICC: 0.133–0.226). Previous studies have shown that differences of > 0.19 in DFA and > 0.66 in SE can differentiate between healthy and pathological gait. These values are greater than this study's reported standard error of measurement, indicating that clinically meaningful changes may still be detectable despite low repeatability. • The repeatability of stride time measures during loaded marching were established • Linear and non-linear measures demonstrated poor-to-moderate repeatability • Non-linear measures had a variation of less than 10 % between sessions • Meaningful changes in stride time measures can be detected during marching [ABSTRACT FROM AUTHOR]

The gait variable minimum toe clearance (MTC) has been investigated concerning trip-related fall research in older adults. However, comparing studies is difficult due to the different methods used to measure MTC and shoe conditions, which may affect agreement. Measurement methods can include using a single virtual point (SVP), multiple virtual points (MVPS), or metatarsal head markers (marker-based). The shoe types used in MTC studies include standard shoes (SS), personal shoes (PS), and barefoot (BF) conditions. What is the agreement, inter and intra-rater reliability, and repeatability for the 3 commonly used methods of measuring MTC (SVP, MVPS, marker-based) under the 3 shoe conditions for optical motion capture systems (SS, PS, BF)? Twelve healthy young adults (mean [SD] 23.8 [1.9] years,7 males) participated in this observational study. In a randomized order, participants completed 25 walking trials at self-selected normal and slow speeds in SS, PS, and BF conditions while infrared cameras recorded the maker trajectories. Each participant performed a familiarization trial for at least 1 minute before collecting data on each shoe condition. Statistical analyses included Bland-Altman 95 % limits of agreement (LOA) analyses, interclass correlation coefficient (ICC) analyses for inter- and intra-rater reliability, and the repeatability coefficient (RC). The SVP and MVPS had a tighter 95 % LOA than the marker-based method, particularly under SS and BF conditions. The inter-rater reliability was good to excellent under these shoe conditions. Intra-reliability for all methods under all shoe conditions was excellent (ICC >.90). The RC was very similar for each method, with none exceeding 1.02 cm. The study provides estimates of the agreement between MTC methods and suggests that only SVP or MVPS produced similar results in SS/BF conditions. Additionally, a "true" change in MTC requires a difference greater than 1.02 cm. • Single and multiple virtual point methods to assess MTC agreed in shoe and barefoot conditions. • The intra-rater reliability was excellent for marker and virtual point methods of assessing MTC. • "True" change in MTC requires a difference greater than 1.02 cm. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Udder conformation is directly related to milk yield, cow health, workability, and welfare. Automatic milking systems (AMS, also known as milking robots) have become popular worldwide, and the number of dairy farms adopting these systems has increased considerably over the past years. In each milking visit, AMS record the location of the 4 teats as Cartesian coordinates in an xyz plan, which can then be used to derive udder conformation traits. Because AMS generate a large amount of data for individual cows per milking visit, they can contribute to an accurate assessment of important traits such as udder conformation without the addition of human classifier errors (in subjective scoring systems). Therefore, the primary objectives of this study were to estimate genomic-based genetic parameters for udder conformation traits derived from AMS records in North American Holstein cattle and to assess the genetic correlation between the derived traits for evaluating the feasibility of multitrait genomic selection for breeding cows that are more suitable for milking in AMS. The Cartesian teat coordinates measured during each milking visit were collected by 36 milking robots in 4,480 Holstein cows from 2017 to 2021, resulting in 5,317,488 records. A total of 4,118 of these Holstein cows were also genotyped for 57,600 SNPs. Five udder conformation traits were derived: udder balance (UB, mm), udder depth (UD, mm), front teat distance (FTD, mm), rear teat distance (RTD, mm), and distance front–rear (DFR, mm). In addition, 2 traits directly related to cow productivity in the system were added to the study: daily milk yield (DY) and milk electroconductivity (EC; as an indicator of mastitis). Variance components and genetic parameters for UB, UD, FTD, RTD, DFR, DY, and EC were estimated based on repeatability animal models. The estimates of heritability (± SE) for UB, UD, FTD, RTD, DFR, DY, and EC were 0.41 ± 0.02, 0.79 ± 0.01, 0.53 ± 0.02, 0.40 ± 0.02, 0.65 ± 0.02, 0.20 ± 0.02, and 0.46 ± 0.02, respectively. The repeatability estimates (± SE) for UB, UD, FTD, RTD, and DFR were 0.82 ± 0.01, 0.93 ± 0.01, 0.87 ± 0.01, 0.83 ± 0.01, and 0.88 ± 0.01, respectively. The strongest genetic correlations were observed between FTD and RTD (0.54 ± 0.03), UD and DFR (−0.47 ± 0.03), DFR and FTD (0.32 ± 0.03), and UD and FTD (−0.31 ± 0.03). These results suggest that udder conformation traits derived from Cartesian coordinates from AMS are moderately to highly heritable. Furthermore, the moderate genetic correlations between these traits should be considered when developing selection subindexes. The most relevant genetic correlations between traits related to cow milk productivity and udder conformation traits were between UD and EC (−0.25 ± 0.03) and between DFR and DY (0.30 ± 0.04), in which both genetic correlations are favorable. These findings will contribute to the design of genomic selection schemes for improving udder conformation in North American Holstein cattle, especially in precision dairy farms. [ABSTRACT FROM AUTHOR]

The targeted placement of selected carbon nanotubes is associated with low throughput rates. Hence, this paper presents a novel stage design for the fully automatic assembly of carbon nanotube field-effect transistors (CNTFETs) via mechanical dry transfer. It constitutes the core module of an assembly machine for the precise deployment of nanotubes onto a prefabricated wafer. The mechanical dry transfer approach allows high level of carbon nanotube selectivity with the aim of enabling a high-volume fabrication of ultra-clean devices. The previous production rate of such ultra-clean devices is less than one per hour, which offers a high potential for improvement. The stage consists of a parallel kinematic mechanism (PKM) with 3 degrees of freedom ( X 2 Y 2 C 1 ) carrying two additional stacked axes ( Z 1 C 2 ). The PKM is suspended on a vacuum preloaded aerostatic bearing, voice coil motors (VCM) and flexure hinges. Together with a combination of high precision and resolution touch probe measurement systems close to its tool center point (TCP), high accuracy and low settling time can be achieved. Based on realistic manufacturing tolerances, a sensitivity analysis of the mechanism's pseudo rigid body model (PRBM) suggests a theoretical closed-loop error below 0. 15 μ m over the entire XY workspace of 20 mm × 2. 8 mm. Measurements of positioning motions show that the settling time can be decreased by the compensation of friction resistances inside the internal bearings of the VCMs. [Display omitted] • Parallel kinematic micromanipulator with novel axis configuration. • Non-monolithic flexure hinge/voice coil combination. • Sensitivity analysis for the accuracy assessment of the manipulator. • Significant reduction of overshoot and settling time. [ABSTRACT FROM AUTHOR]

• An ECFS-endorsed SOP was used to measure CFTR function using forskolin-induced swelling. • The Forskolin-induced swelling (FIS) assay demonstrates high repeatability and reproducibility. • Identical patient-derived organoids were shared with different laboratories. • Forskolin-induced swelling is a technically reliable biomarker of CFTR function. • Intestinal organoids may be used for cystic fibrosis precision medicine applications. The forskolin-induced swelling (FIS) assay measures CFTR function on patient-derived intestinal organoids (PDIOs) and may guide treatment selection for individuals with Cystic Fibrosis (CF). The aim of this study is to demonstrate the repeatability and reproducibility of the FIS assay following a detailed Standard Operating Procedure (SOP), thus advancing the validation of the assay for precision medicine (theranostic) applications. Over a 2-year period, FIS responses to CFTR modulators were measured in four European labs. PDIOs from six subjects with CF carrying different CFTR genotypes were used to assess the repeatability and reproducibility across the dynamic range of the assay. Technical, intra-assay repeatability was high (Lin's concordance correlation coefficient (CCC) 0.95–0.98). Experimental, within-subject repeatability was also high within each lab (CCCs all >0.9). Longer-term repeatability (>1 year) showed more variability (CCCs from 0.67 to 0.95). The reproducibility between labs was also high (CCC ranging from 0.92 to 0.97). Exploratory analysis also found that between-lab percentage of agreement of dichotomized CFTR modulator outcomes for predefined FIS thresholds ranged between 78 and 100 %. The observed repeatability and reproducibility of the FIS assay within and across different labs is high and support the use of FIS as biomarker of CFTR function in the presence or absence of CFTR modulators. [ABSTRACT FROM AUTHOR]

Diffusion weighted imaging (DWI) with optimized motion-compensated gradient waveforms reduces signal dropouts in the liver and pancreas caused by cardiovascular-associated motion, however its precision is unknown. We hypothesized that DWI with motion-compensated DW gradient waveforms would improve apparent diffusion coefficient (ADC)-repeatability and inter-reader reproducibility compared to conventional DWI in these organs. In this IRB-approved, prospective, single center study, subjects recruited between October 2019 and March 2020 were scanned twice on a 3 T scanner, with repositioning between test and retest. Each scan included two respiratory-triggered DWI series with comparable acquisition time: 1) conventional (monopolar) 2) motion- compensated diffusion gradients. Three readers measured ADC values. One-way ANOVA, Bland-Altman analysis were used for statistical analysis. Eight healthy participants (4 male/4 female), with a mean age of 29 ± 4 years, underwent the liver and pancreas MRI protocol. Four patients with liver metastases (2 male/2 female) with a mean age of 58 ± 5 years underwent the liver MRI protocol. In healthy participants, motion-compensated DWI outperformed conventional DWI with mean repeatability coefficient of 0.14 × 10−3 (CI:0.12–0.17) vs. 0.31 × 10−3 (CI:0.27–0.37) mm2/s for liver, and 0.11 × 10−3 (CI:0.08–0.15) vs. 0.34 × 10−3 (CI:0.27–0.49) mm2/s for pancreas; and with mean reproducibility coefficient of 0.20 × 10−3 (CI:0.18–0.23) vs. 0.51 × 10−3 (CI:0.46–0.58) mm2/s for liver, and 0.16 × 10−3 (CI:0.13–0.20) vs. 0.42 × 10−3 (CI:0.34–0.52) mm2/s for pancreas. In patients, improved repeatability was observed for motion-compensated DWI in comparison to conventional with repeatability coefficient of 0.51 × 10− 3 mm2/s (CI:0.35–0.89) vs. 0.70 × 10−3 mm2/s (CI:0.49–1.20). Motion-compensated DWI enhances the precision of ADC measurements in the liver and pancreas compared to conventional DWI. [ABSTRACT FROM AUTHOR]

This paper describes and illustrates a convenient, new method for checking repeatability and reproducibility by direct comparisons of measured heights. Focus variation, confocal, and interferometric optical areal profiling have been integrated as modes on the Sensofar S neox and are used here. Repeated, sequential measurements are made with these different types of measurement without repositioning the measurand. Several different positions are measured on the same measurand, an electroformed, standard areal surface with an irregular topography. Height (z) measurements at individual locations (x,y) are plotted between repeated measurements at the same position on the measurand, and are called H–H plots. These plots can be used for rapid evaluations of topographic measurement repeatability on ordinary topographic measurements. Exceptionally, such plots can also be used to see how well one type of measurements can reproduce another, such as confocal, focus variation, and interferometric, when they are integrated as modes on the same measurement instrument. Only when different types of measurement are included as modes on the same instrument can different measurement types be compared directly for reproducing each of the large numbers of locations (>105) in topographic measurements at the same position on a measurand. One way of quantifying repeatability and reproducibility is with coefficients of determination (R2) and slopes of linear regression analyses on these H–H plots. • Direct comparison of heights in repeated topographic measurements by linear regression. • Reproducibility between confocal, focus variation and interferometric measurements. • Method for estimating topographic measurement repeatability in actual conditions. [ABSTRACT FROM AUTHOR]

The study investigated the repeatability of brain diffusion-based stiffness prediction (DWI stiff) in healthy volunteers. Thirty-one healthy volunteers were examined with DWI stiff using two different sets of b-values: b200-1500 s/mm2 (DWI stiff , 1500) and b200-1000 s/mm2 (DWI stiff , 1000). Each b-value set was scanned twice per imaging session without repositioning the participants. DWI stiff images were reconstructed from each set. Two observers delineated regions of interest (ROIs) on each DWI stiff image. The repeatability coefficient (RC), coefficient of variation (CV), inter- and intraobserver agreement were calculated. After excluding three participants due to image artifacts, the study included twenty-eight volunteers (mean age (range)) 37 years (24–62), 10 males, 18 females). For DWI stiff , 1500, the lowest and the highest RCs were in the parietal lobe (0.52) and respectively the brain stem (1.17). The lowest RC for DWI stiff , 1000 was in the frontal lobe (0.42) and the highest in the brain stem (1.58). The CV for whole brain measurements was 3.83 % for DWI stiff , 1500 and 4.93 % for DWI stiff , 1000. The Bland‒Altman (BA) limits of agreement (LoA) for the intraobserver agreement of DWI stiff , 1500 were −0.90 to 1.06 and respectively −0.78 to 0.88 for DWI stiff , 1000. Regarding interobserver agreement, the LoA were −0.85 to 0.94 for DWI stiff , 1500 and −0.61 to 0.66 for DWI stiff , 1000. DWI stiff is a precise technique with some observer dependence. Repeatability is higher for DWI stiff , 1000 s/mm2 than for DWI stiff 1500 s/mm2. Our findings suggest that DWI stiff can reliably detect stiffness changes larger than 4.93 % in healthy volunteers. Further studies should investigate whether the repeatability of DWI stiff may be affected by the presence of pathology such as a brain tumor. [ABSTRACT FROM AUTHOR]

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To achieve a wide operating velocity range, stepping without backward motion, and high positioning resolution, a walking-type piezoelectric actuator with compliant mechanisms is developed. There are few academic research reports on this type of actuator, and this paper clarifies the features and advantages of this actuator. A systematic modeling and experimental evaluation of the proposed actuator are carried out. First, the configuration of the proposed actuator and the working principle of the alternating elliptical movements of the two driving feet are described. Then, dynamic models are built to simulate the output characteristics of the proposed actuator with in-phase and opposite-phase drive, which provide guidance for the design and optimization of walking-type actuators. An actuator prototype is fabricated and experimentally evaluated. The experimental results indicate that, under the opposite-phase drive, the proposed actuator can operate at a driving frequency of 1–15000 Hz. At a frequency of 14000 Hz, a maximum velocity of 24.6 mm/s is achieved at a voltage of 36 V pp , and the dead zone of the actuator is 0–6 V pp. A step displacement of 2.25 μm without backward motion is accomplished at a voltage of 72 V pp and a frequency of 1 Hz. Furthermore, the positioning resolution in the forward and reverse directions are 144 and 152 nm, respectively. The repeatability of the actuator is ±25 to ±50 nm for strokes of 325–725 nm, respectively. Therefore, compared to two driving feet being driven in phase, driving them in opposite phase as if they were walking has been confirmed to increase thrust, shorten the rise time, reduce the dead zone of driving voltage, eliminate backward motion, and provide high repeatability. • A piezoelectric actuator with triangular compliant mechanisms is first developed. • Dynamic models in the x - and y -directions are established for performance evaluation. • The actuator achieves a wide operating velocity range, no backward motion, and high-precision positioning. [ABSTRACT FROM AUTHOR]

High-precision handling processes are essential for various high-tech industries and are typically realized using specialized high precision robots. Articulated robots are rarely used for such tasks due to their low stiffness and accuracy stemming from their kinematic structure. This work presents a methodology for designing handling processes that maximise repeatability with articulated robots. By considering their kinematic structures' highly pose dependent properties as well as sensitivity to external disturbances in every step of the processes design, significantly improved repeatability can be achieved. The applicability of the new methodology is verified experimentally using the example of handling of large silicon dies. [ABSTRACT FROM AUTHOR]

In this study a 3-dimensional (3D) camera system was set up to measure individual feed intake of dairy cows in a commercial in-house setting. The system was developed to identify the cows while eating, predict body weight based on the curvature of the back of the cow, and quantify the amount of feed eaten by the cow at each visit of eating. The identification of the cow was based on recognizing the patterns, colors, and curvatures of the back from a reference database obtained in a corridor after milking, where images were taken of all cows with a simultaneous reading of the electronic ear tag. Body weight is predicted using the curvatures of the back of the cow. Feed intake is quantified as the difference in surface of the feed a cow can reach before and after a visit is initiated. This estimate is in liters but converted to kilograms, using the density of the feed in the specific herd. A total of 9,142 cows were measured in 19 herds across 3 breeds: Jersey (2,513 cows), Red Dairy Cattle (2,813 cows), and Holstein (3,816 cows). Mean daily feed intake was higher for Red Dairy Cattle (61.72 kg) and Holstein (64.59 kg) than for Jersey (55.74 kg). Repeatability estimates for daily feed intake as a weekly average was 0.62, 0.65, and 0.63 for Jersey, Red Dairy, and Holstein cattle, respectively. Mean body weight was higher for Red Dairy (647.9 kg) and Holstein (683.8 kg) than for Jersey (469.6 kg). Repeatability estimates for body weight as a weekly average was 0.83, 0.85, and 0.88 for Jersey, Red Dairy, and Holstein, respectively. The perspectives in having such records available is huge both for the farmer and for the dairy industry. The records can both be used for improving management in farms on an individual cow level and herd level, but also for genetic evaluation and selection as well as testing feeding regimens. Feed intake can be measured on an individual level using a 3D camera system. [ABSTRACT FROM AUTHOR]

The dynamic optotype (DYOP) visual acuity (VA) test is based on motion detection rather than element resolution and has been proposed for routine clinical assessment. This investigation examined the validity, inter- and intra-session repeatability and subjective preference for the DYOP versus a static letter chart and examined its utility in detecting astigmatic defocus. VA of 103 participants was measured three times with the letter and DYOP charts and repeated within two weeks in 75 participants who also rated their subjective experience. The VA of 29 participants was measured using DYOP, letter, Landolt C, and Tumbling E charts, with habitual correction and astigmatism induced with +1.00, +2.00 or +3.00 cylinders at 45, 60, 90 and 180°. The charts differed by a mean of 0.02 logMAR, with 81% of the measurements within one line of acuity. Inter-session, intraclass correlation coefficients, within-subject SD and repeatability were 0.03 logMAR, 0.95, 0.11 and 0.30 versus 0.01 logMAR, 0.92, 0.15 and 0.42 for the DYOP and letter charts, respectively. The DYOP was significantly more frustrating (1.79 vs.1.36), with 59% preferring the letter chart. The DYOP was least affected by induced astigmatism. The DYOP and letter charts differed significantly in their mean values with wide limits of agreement. DYOP had better within-subject SD and narrower limits of agreement between sessions, though clinically insignificant, and performed significantly worse for the detection of uncorrected astigmatism. Thus, it is difficult to recommend this test for the clinical determination of refractive error. [ABSTRACT FROM AUTHOR]

• To test MScanFit MUNE repeatability, 15 centres recorded CMAP scans from 148 healthy subjects twice from ADM, APB and TA muscles. • The coefficients of variation between repeats were 18.0% for ADM, 16.8% for APB, and 12.1% for TA with revised MScanFit-2 version. • CMAP amplitudes differed significantly between centres for all muscles whereas MUNE using MScanFit-2 differed only for APB. To assess the repeatability and suitability for multicentre studies of MScanFit motor unit number estimation (MUNE), which involves modelling compound muscle action potential (CMAP) scans. Fifteen groups in 9 countries recorded CMAP scans twice, 1–2 weeks apart in healthy subjects from abductor pollicis brevis (APB), abductor digiti minimi (ADM) and tibialis anterior (TA) muscles. The original MScanFit program (MScanFit-1) was compared with a revised version (MScanFit-2), designed to accommodate different muscles and recording conditions by setting the minimal motor unit size as a function of maximum CMAP. Complete sets of 6 recordings were obtained from 148 subjects. CMAP amplitudes differed significantly between centres for all muscles, and the same was true for MScanFit-1 MUNE. With MScanFit-2, MUNE differed less between centres but remained significantly different for APB. Coefficients of variation between repeats were 18.0% for ADM, 16.8% for APB, and 12.1% for TA. It is recommended for multicentre studies to use MScanFit-2 for analysis. TA provided the least variable MUNE values between subjects and the most repeatable within subjects. MScanFit was primarily devised to model the discontinuities in CMAP scans in patients and is less suitable for healthy subjects with smooth scans. [ABSTRACT FROM AUTHOR]

Ratiometric thermometry based on lanthanide-activated phosphors is the most reliable method to measure the thermometric figures of merit due to its self-referencing ability. In this work, we use the rarely investigated Raman and photoluminescence intensity ratio (RPIR) method to evaluate the high-temperature sensitivity of a double perovskite phosphor Ba 2 Y 2/3 TeO 6 : 2.5% Eu3+ for the first time. The phosphor exhibits a maximum relative sensitivity of 0.52% K−1 at 573 K with a temperature resolution of 0.17 K. The study proved the RPIR method as a promising strategy for high-temperature optical thermometry using crystalline solids. [Display omitted] [ABSTRACT FROM AUTHOR]

Adult walleye (Sander vitreus) conduct annual migrations from riverine spawning sites in the Bay of Quinte into the eastern basin of Lake Ontario to forage. Although fidelity to spawning river is quite high for these fish across the Laurentian Great Lakes, very little is known about the repeatability of site selection along the entirety of their annual migration. This study used multiple years of acoustic telemetry (2018–2020) to assess the within-individual repeatability of the timing associated with major migratory events (spawning river entry and departure, main lake entry and departure), as well as the average monthly spatial distribution of individuals throughout the year. Fine-scale sequence analysis was used to combine these two metrics to assess the within and among individual sequence dissimilarity in the population. Within-individual repeatability was high across most timing and spatial measures, and the sequence dissimilarity within individual sequences was significantly less than that among individuals. Sex and size were not significantly related to sequence dissimilarity, while individuals from the Trent River displayed more dissimilarity than those from the Napanee River. The high level of within-individual annual repeatability in migrations was demonstrated not only during spawning activity, but at a daily level throughout the entire year. This research shows that walleye possess the ability to orient themselves and navigate across long distances in a highly repeatable manner at all times of the year. Future work will be required to better understand the underlying mechanisms and drivers behind these abilities. [ABSTRACT FROM AUTHOR]

The reliability of the result significantly affects the use of the Coefficient of Variation (within the test variation), which reflects the variability of the concrete properties rather than the standard deviation. For the estimation of reliability and precision, comprehensive statistical analysis (within test variation) is conducted on 534 test samples using a rebound hammer. Different standards, like BIS, EN, ACI, and ASTM, are used in this study to compare the test results. Empirical research revealed that there are contradictions in literature as well as the standards used in many countries. The present paper focuses on detailed investigations of uncertainty measurements of the surface hardness test by statistical parameters (range of rebound index, standard deviation, and Coefficient of Variation). The unbiased estimate of the variability parameters from the published results has been verified concerning to the European standard. Concrete parameters namely cement type, water to cement ratio, compaction deficiency, curing condition, and elevated temperature have an impact on the output of the rebound hardness in terms of the variability of the compressive strength. Based on the results, the authors are willing to propose amendments to the Indian code graciously in compliance with the variability of the rebound hammer. [ABSTRACT FROM AUTHOR]

This study investigated the validity and reliability of measuring patellar tendon (PT) cross-sectional area (CSA) using magnetic resonance imaging (MRI) and ultrasound (US) imaging. Nineteen healthy participants (10 women, 9 men) participated in three imaging sessions of the PT, once via MRI and twice via US, with image acquisition conducted by two raters, one experienced (rater 2) and one inexperienced (rater 1). All PT segmentations were analyzed by both raters. The validity of US-derived estimates of PT CSA against MRI estimates was analyzed using linear regression. Within-day reliability of US and MRI measurements and between-day reliability of US measurements were quantified using typical error (TE) and intra-class correlation coefficients (ICC3,1). There was good agreement between US- and MRI-derived estimations of PT CSA (standard errors of the estimate of 3.3 mm2 for rater 1 and 2.6 mm2 for rater 2; Pearson's r = 0.97 and 0.98 for raters 1 and 2, respectively). Within-session reliability for estimations of total PT CSA from US and MRI were excellent (ICC3,1 >0.95, coefficient of variation [CV] <4.1%, TE = 1.3-3.6 mm2. Between-day reliability for US was excellent (ICC3,1 >0.97, CV <2.7%, TE = 1.6-2.3 mm2), with little difference between raters. These findings suggest that MRI and US both provide reliable estimates of PT CSA and that US can provide a valid measure of PT CSA. [ABSTRACT FROM AUTHOR]

To evaluate regurgitant fraction (RF) using Simpson's method of discs to estimate total stroke volume (RF SMOD_TSV) and using Motion-mode to estimate total stroke volume (RF M-modeTSV) in dogs with subclinical myxomatous mitral valve disease (MMVD). We also sought to evaluate the effects of pimobendan on RF, and to determine the reproducibility of RF SMOD_TSV and RF M-modeTSV. Echocardiography was performed on 57 dogs with MMVD (30 stage B1 and 27 stage B2). Ten dogs received pimobendan for 7–10 days and had a second echocardiogram. Nine dogs underwent six repeated echocardiographic examinations by two operators on three nonconsecutive days within one week for reproducibility analysis. Both RF SMOD_TSV and RF M-modeTSV exhibited a curvilinear relationship with left atrium-to-aortic root ratio. Both RF SMOD_TSV and RF M-modeTSV varied considerably within stage B1 (minimum–maximum: −9.1%–58.2% and −35.7%–66.2%, respectively) and B2 (13.6%–76.2% and 20.1%–85.7%, respectively). Method comparison showed RF SMOD_TSV and RF M-modeTSV were not interchangeable with proportional bias. Pimobendan significantly reduced RF SMOD_TSV (−32.0% ± 23.3%) and RF M-modeTSV (−19.2% ± 10.9%) within the same dog and relative to controls. Good inter-day and between-operator reproducibility was observed for RF SMOD_TSV and RF M-modeTSV based on intraclass correlation coefficients 0.86–0.90 and 0.83–0.90, respectively. Reproducibility coefficients were 19.6%–24.1% and 24.1%–27.0%, respectively. Use of RF using the total stroke volume method to aid the assessment of dogs with subclinical MMVD might be of clinical value. However, further study is warranted. Based on response to pimobendan and reproducibility analysis, RF SMOD_TSV might be a more reliable technique to quantify RF. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the multi-vendor multi-site reproducibility of two-dimensional (2D) multi-echo spin-echo (MESE) T2 mapping (product sequences); and to evaluate the longitudinal reproducibility of three-dimensional (3D) magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (MAPSS) T1ρ and T2 mapping (research sequences), and 2D MESE T2 mapping, separated by 6 months, in a multi-vendor multi-site setting.Methods: Phantoms and volunteers (n = 5 from each site, n = 20 in total) were scanned on four 3 T magnetic resonance (MR) systems from four sites and three vendors (Siemens, General Electric, and Phillips). Two traveling volunteers (3 knees) scanned at all 4 sites at baseline and 6-month follow-up. Data was transferred to one site for centralized processing. Coefficients of variation (CVs) were calculated to evaluate reproducibility.Results: For baseline 2D MESE T2 measures, average CV were 0.37-2.45% (intra-site) and 5.96% (inter-site) for phantoms, and 3.15-8.49% (intra-site) and 14.16% (inter-site) for volunteers. For longitudinal phantom data, intra-site CVs were 1.42-3.48% for 3D MAPSS T1ρ, 1.77-3.56% for 3D MAPSS T2, and 1.02-2.54% for 2D MESE T2. For the longitudinal volunteer data, the intra-site CVs were 2.60-4.86% for 3D MAPSS T1ρ, 3.33-7.25% for 3D MAPSS T2, and 3.11-8.77% for 2D MESE T2.Conclusion: This study demonstrated excellent intra-site reproducibility of 2D MESE T2 imaging, while its inter-site variation was slightly higher than 3D MAPSS T2 imaging (10.06% as previously reported). This study also showed excellent reproducibility of longitudinal T1ρ and T2 cartilage quantification, in a multi-vendor multi-site setting for both product 2D MESE T2 and 3D MAPSS T1p/T2 research sequences. [ABSTRACT FROM AUTHOR]

The footwear assessment tool was designed to advise an appropriate footwear for each situation and patient. Footwear alterations structures can influence in musculoskeletal disorders, developing foot ulcers, increase the peak plantar pressure, bacterial growth, low back pain. Methods: To validate the study 101 subjects were recruited. The study was tested by two expert podiatrists using the tool for the assessment of footwear characteristics that is composed by five domains, fit, general features, general structure, motion control properties and cushioning system. Each domain analyzes different shoe items. Results: An excellent agreement between the test-retest. A suitable Cronbach's α was suggested for the five domains of fit (α = 0.952), general features (α = 0.953), general structure (α = 0.947), motion control properties (α = 0.951), and cushioning system (α = 0.951). Test-retest reliability was excellent for all domains. There were no significant differences between any domain (p > 0.05). There was only statistically significant difference in the item forefoot height (p = 0.011). For all the domains items there were no statistically significant difference (p > 0.05). Conclusions: The tool for the assessment European footwear is a suitable repeatability and reliability footwear tool that can be used in Spanish language subjects. • A footwear tool is useful to the shoe management. • A footwear tool is reliability and repeatability for shoe management. • The footwear tool advice in fit, general features, general structure, motion control properties and cushioning system. [ABSTRACT FROM AUTHOR]

Biocompatibility evaluation of medical devices often relies on chemical testing according to ISO 10993–18 as a critical component for consideration. However, the precision associated with these non–targeted chemical characterization assessments has not been well established. Therefore, we have conducted a study to characterize intra–laboratory (repeatability) and inter–laboratory (reproducibility) variability associated with chemical testing of extractables from polymeric materials. To accomplish this, this study focused on two polymers, each with nine chemicals that were intentionally compounded into the materials. Eight different laboratories performed extraction testing in two solvents and subsequently characterized the extracts using gas chromatography and liquid chromatography methods. Analysis of the resulting data revealed the central 90 % range for the repeatability and reproducibility relative standard deviations are (0.09, 0.22) and (0.30, 0.85), respectively, for the participating laboratory methods. This finding implies that if the same sample was tested by two different laboratories using the same extraction conditions, there is 95 % confidence for 95 % of systems that the test results could exhibit differences up to 240 %. While the study was not designed to evaluate the relative impact of specific underlying factors that may contribute to variability in quantitation, the data obtained suggest the variability associated with analytical method alone is a substantial contribution to the overall variability. The relatively large reproducibility limits we observed may have significant implications where variability in extraction measurements can impact aspects of biocompatibility risk evaluation, such as exposure dose estimation and chemical equivalence assessments. • Established repeatability and reproducibility in medical device extraction studies. • Differences in quantitation ranged from 0.5 to 1 orders of magnitude. • Between laboratory variability 4x higher than within laboratory variability. • Differences in analytical methods are a major contributor to overall variability. • Non-targeted analytes inconsistently reported, but chemically similar. [ABSTRACT FROM AUTHOR]

One of the key obstacles in forest breeding routines is the time-consuming steps of selection and recombination of superior genotypes owing to the long life cycle of trees. Considering the increase in global temperature and constant climate alterations, the quick selection of genetic materials is crucial to ensure the effectiveness of genetic improvement programs. Early selection studies on other forest species are scarce, barring eucalyptus and pine, which are well-studied crops. In this context, this study aimed to understand the efficiency of early selection in a progeny test of Cordia trichotoma (Vell.) Arráb. ex Steud to evaluate age-age trends, genetic variability, and potential gains. A progeny test was conducted and measured at three, six, and eight years of age for growth traits, diameter, and volume increment. The experiment included 21 open-pollinated families of C. trichotoma arranged in a 4 × 4 m experimental design grid with a single-tree plot distributed into 10 blocks. The genetic correlations among the three measurements for genitor selection were greater than 0.90 for all the traits. For every ten progenies selected at three years of age, approximately seven were determined to be similarly top-ranked at eight years of age, taking into account an early selection assertiveness rate of approximately 0.70 for progenies. Considering the high age-age genetic correlation found in the C. trichotoma progeny test, there is a significant possibility of improving genetic gains per unit of time through early selection. The general mean of volume increment was 18 m3 ha−1 year−1, with productive genotypes showing a volume greater than 30 m3 ha−1 year−1 and representing an estimated general gain of 66 %. Superior genotypes of C. trichotoma are highly competitive in terms of volumetric yield, can generate considerable gains, and are used in the forest industry. Early selection of C. trichotoma is efficient, with a high rate of assertiveness. • Early selection of C. trichotoma is efficient, with a high rate of assertiveness. • Age-age genetic correlation is greater for genitors than progenies. • Top-ranked C. trichotoma trees yield above 30 m3 ha-1 year-1. • Genetic gains of superior C. trichotoma genotypes can reach 66 %. • C. trichotoma are highly competitive and can be large-cropped for the industry. [ABSTRACT FROM AUTHOR]

Cardiac-related mortality is increasing in farmed salmon. Non-invasive tools for examining and screening for cardiac morphology and function are limited, and most common methodologies are lethal, time-consuming, and immobile. Echocardiography has previously been tested as a non-invasive, quick, and portable alternative, though its implementation is minimal. Improvements in echocardiographic techniques during the last decade have enabled more refined assessments of structure and function and hold potential for use in fish farms. Utilising a compact, transportable ultrasound system, we examined the applicability of echocardiography in Atlantic salmon (Salmo salar L.). Several protocols and projections were tested, and intra- and inter-variation for both operators (image acquisition) and observers (image analysis) were assessed. In addition, the accuracy of cardiac structure/function measurements was compared with standard methods. In general, high accuracy and reproducibility of cardiac dimensions and functional parameters were found within the same and between different observers analysing the same dataset (intra- and inter-observer). Measurements between recordings of the same operator (intra-operator) and between different operators (inter-operator) were less accurate and repeatable but comparable to observations in previous human and mammalian studies. Cardiac output was slightly higher when measured with echocardiography compared to transit time flow probe. Yet, a strong correlation exists between the two methods. Furthermore, morphology measured in excised hearts ex vivo was comparable to echocardiography measurements and strongly correlated. Thus, ultrasound presents a highly feasible, non-invasive, and swift alternative to current methods for detailed cardiac assessment of salmon hearts. • Echocardiography is a non-invasive option for cardiac analysis in Atlantic salmon. • Intra- and inter-variability is comparable to human and mammalian studies. • Echocardiography yields measurements similar to invasive methods. [ABSTRACT FROM AUTHOR]

In this paper, Lu 2.97 Al 5–x Ga x O 12 :Ce 0.03 (x = 0, 1, 2, 3) nanophosphors were synthesized using sol-gel method and calcined at 1100 °C for 3 h. The effect of Ga content on the structural, photoluminescence (PL), and notably thermoluminescence (TL) glow curve, dose response, repeatability and fading properties were investigated. X-ray diffraction (XRD) results indicated that all synthesized samples were crystallized in a pure garnet phase. The PL emission spectra exhibited a broad emission band corresponding to the 5 d → 4f (2F 5/2 , 2F 7/2) transition of Ce3+ ions in the garnet lattice. Furthermore, a significant decrease in emission intensity was observed upon increasing Ga content. The TL characteristics of nanopowders irradiated with β-rays revealed a significant effect of Ga content on the peak position, shape and intensities of TL Glow curves, which can be explained by the reduction of the energy gap and the distribution of trap levels. The dose response linearity in the range of 0.125–100 Gy was examined for different Ga content, revealing a good linear behavior for x = 0 and 1 Ga. Additionally, samples prepared with x = 0, 1, and 2 Ga exhibited a high level of repeatability across a batch of 10 samples. Also, fading studies were performed for 128 h and revealed strong fading in samples synthesized with x = 0 and 1 Ga. These results suggest potential applications of Lu 3 Al 5 O 12 :Ce and Lu 3 Al 4 Ga 1 O 12 :Ce in ionizing radiation dosimetry. • Lu 3 Al 5-x Ga x O 12 :Ce3+ (x = 0, 1, 2 and 3) nanophosphors were successfully synthesized using sol–gel method. • Thermoluminescence properties of prepared nanophosphors exhibited a strong dependence on Ga content. • Single garnet phase was obtained for all prepared nanophosphors. • Lu 3 Al 5-x Ga x O 12 :Ce 0.03 demonstrated a good linear behavior within the range 0.125–100 Gy for x = 0 and x = 1. • Nanophosphors prepared with Ga content of x = 0 and x = 1 displayed perfect repeatability and indicated a remarkably strong fading. [ABSTRACT FROM AUTHOR]

The relative efficacy of electrochemical permeation (EP) and isothermal desorption spectroscopy (ITDS) methods for determining the hydrogen diffusivity is investigated using cold-rolled pure iron. The diffusivities determined from 13 first transient and 8 second transient EP experiments, evaluated using the conventional lag and breakthrough time methods, are compared to the results of 10 ITDS experiments. Results demonstrate that the average diffusivity is similar between the second EP transient and ITDS, which are distinctly increased relative to the first EP transient. However, the coefficient of variation for the ITDS experiments is reduced by 2 and 3-fold relative to the first and second EP transients, confirming the improved repeatability of ITDS diffusivity measurements. The source of the increased error in EP measurements is systematically evaluated, revealing an important influence of assumed electrochemical boundary conditions on the analysis and interpretation of EP experiments. [Display omitted] • Permeation and desorption methods are used to measure hydrogen diffusivity in pure Fe. • The first statistically significant comparison of isothermal desorption and permeation is provided. • Isothermal desorption experiments reduce the coefficient of variation by 3-fold. • Permeation is shown to be very sensitive to the electrochemical boundary conditions. • Isothermal desorption provides accurate and repeatable diffusivity measurements. [ABSTRACT FROM AUTHOR]

The requirements that complex 3D miniaturised components have to satisfy are constantly increasing for various application areas, e.g. in aerospace, biomedical and electronics, and hence there is a sustained drive to broaden the capabilities of precision manufacturing processes. In this regard, state-of-the-art Laser Micro-Machining (LMM) systems have been attracting significant industrial interest with their emerging capabilities for multi-axis machining. However, intrinsic limitations of component technologies of such systems can impact the machining accuracy, repeatability, and reproducibility (ARR), especially in complex processing strategies requiring the simultaneous use of multiple axes, and consequently to affect the overall processing uncertainty. Herein, the aim of this research is to propose a systematic method for assessing the overall performance of such LMM systems when they are deployed for laser structuring/patterning/texturing of freeform surfaces. In particular, the method employs a series of laser processing tests on spherical samples to quantify the contributions of different error sources on the machining ARR when implementing simultaneous multi-axis processing strategies under quasi-static and dynamic conditions. An experimental validation of the proposed method is conducted on a representative state-of-the-art LMM system and then conclusions are drawn about its capabilities to determine the processing ARR of multi-axis LMM systems. This research provides an insight into the limitations and manufacturing challenges in deploying such systems for the fabrication of complex 3D components. [Display omitted] • Multi-axis simultaneous laser strategies offer a higher processing efficiency. • An empirical method is proposed and demonstrated for performance evaluation of multi-axis laser systems. • Machining tests used to identify the combined effects of multiple geometric and motion errors. • The machining capabilities of up to 6-axis simultaneous laser strategies were assessed. • The focus variation optical technology was used for inspecting the machining patterns. [ABSTRACT FROM AUTHOR]

The Podoprint® pressure platform system is widely used in routine podiatric clinical practice to measure plantar pressures. It allows non-invasive examination of the patient, and provides fast results with high levels of precision, reliability, and repeatability. Once these conditions have been demonstrated, the clinical and/or research use of baropodometry allows results to be obtained in the field of podology that are far from inconsiderable. The study was designed to evaluate the repeatability and reliability of the platform, and to identify the normal foot pressure parameters. Records were collected from 52 random healthy individuals, 10 men and 42 women, in two sessions separated by one week. The study variables were: maximum pressure, mean pressure, support surface areas (heel, midfoot, and forefoot), and contact time. Repeatability and reliability were evaluated by calculating the interclass correlation coefficient (ICC) and the coefficient of variation (CV) in the three tests. The ICCs showed moderate to good repeatability for the variables of interest, and the CVs were all less than 18%. The maximum pressure was under the forefoot (mean 2675.4 ± 513.8 g/cm2). The mean contact time of the steps was 0.72 ± 0.07 s. The Podoprint® system is a reliable tool for evaluating the distribution of plantar pressures in the dynamic study of the barefoot gait of healthy individuals. • I am pleased to submit an original research article entitled "The Podoprint ® plantar pressure platform: Evaluation of reliability and repeatability, and determination of the normality parameters" , for consideration for publication in Journal of Tissue Viability. Since the best author's knowledge this is the first paper assessing the reliability and repeatability of the plantar pressure platform " Podoprint ® " .. • In this manuscript, we findings are important for podiatry, as they allow the validation of a device that can be used in the future to carry out scientifically viable studies. • We believe that this manuscript is appropriate for publication by Journal of Tissue Viability, because it is a magazine of great scientific interest and in the future it may contain studies carried out with this method. [ABSTRACT FROM AUTHOR]

To determine the accuracy, repeatability, and reproducibility of magnetic resonance imaging-based proton density fat fraction (MRI-PDFF) measurements of rotator cuff muscles between two readers and three different scanners. Twenty-seven volunteers underwent serial shoulder MRI examinations of both left and right sides on one 1.5-T MRI scanner and two 3.0-T MRI scanners. Two independent readers measured muscular PDFF of the supraspinatus, infraspinatus/teres minor muscle, and subscapularis. MR spectroscopy-based proton density fat fraction (MRS-PDFF) was regarded as the reference standard for assessing accuracy. A "coffee break" examination method was used to test the repeatability of each scanner. Bland-Altman plots, Pearson correlation, and linear regression analysis were used to assess bias and linearity. The Wilcoxon signed-rank test and Friedman test were applied to evaluate repeatability and reproducibility. MRI-PDFF measurements indicated strong linearity (R2 = 0.749) and small bias (−0.18%) in comparison with the MRS-PDFF measurements. A very strong positive Pearson correlation (r = 0.955–0.986) between the PDFF estimates of the two repeat scans indicated excellent repeatability. The PDFF measurements showed high reproducibility, with a strong positive Pearson correlation (r = 0.668–0.698) and a small mean bias (−0.04 to −0.10%) across different scanners. MRI-PDFF measurements of rotator cuff muscles were highly accurate, repeatable, and reproducible across different readers and scanners, leading us to the conclusion that PDFF can be a reliable and robust quantitative imaging biomarker for longitudinal or multi-center studies. [ABSTRACT FROM AUTHOR]

• Mean repeatability of apparent diffusion coefficient values was between 13 and 31%. • Lower repeatability values were correlated with larger volumes. • Intraclass correlation coefficient was 0.75 for gross tumor volume. • Diffusion-weighted imaging is possible basis for future adaptive radiotherapy. Functional information acquired through diffusion-weighted magnetic resonance imaging (DW-MRI) may be beneficial for personalized head and neck cancer (HNC) radiotherapy. Technical validation is required before DW-MRI based radiotherapy interventions can be realized clinically. The aim of this study was to assess the repeatability of apparent diffusion coefficients (ADC) derived from DW-MRI in HNC using echo-planar imaging (EPI) on a 1.5 T MR-Linac. A total of eleven HNC patients underwent test/retest DW-MRI scans at least once per week during fractionated radiotherapy at the MR-Linac. An EPI DW-MRI test scan (b = 0, 150, 500 s/mm2) was acquired before the start of adaptive MR-guided radiotherapy in addition to an identical retest scan after irradiation. Volumes-of-interest (VOI) were defined manually for parotid (PTs) and submandibular glands (SMs), gross tumor volume (GTV) and lymph nodes (LNs). Mean ADC was calculated for all VOI in all test/retest scans. Absolute/relative repeatability coefficients (RCs/relRCs) as well as intraclass correlation coefficients (ICCs) were determined for all VOIs. A total of 81 datasets were analyzed. Mean test ADC values were 1380/1416, 950/1010, 1520 and 1344 · 10−6 mm2/s for left/right SM and PT, GTV and LNs, respectively. Accordingly, RC (relRC) values were determined as 271/281 (19.4/21.8%) and 138/155 (13.3/15.2%), 457 (31.3%) and 310 · 10−6 mm2/s (23.5%). ICC resulted in 0.80/0.87, 0.97/0.94, 0.75 and 0.83 for left/right SM and PT, GTV and LNs, respectively. The repeatability of ADC derived from EPI DW-MRI at the 1.5 T MR-Linac appears reasonable to be used for future biologically adapted MR-guided radiotherapy. [ABSTRACT FROM AUTHOR]

• Reproducibility and repeatability of a dementia MRI protocol were assessed. • Functional imaging markers were more variable than structural ones. • Short-term repeatability was better than long-term repeatability. • Reproducibility was comparable to long-term repeatability. • Results support viability of multi-site, longitudinal studies of cognitive decline. Individualised predictive models of cognitive decline require disease-monitoring markers that are repeatable. For wide-spread adoption, such markers also need to be reproducible at different locations. This study assessed the repeatability and reproducibility of MRI markers derived from a dementia protocol. Six participants were scanned at three different sites with a 3T MRI scanner. The protocol employed: T1-weighted (T1w) imaging, resting state functional MRI (rsfMRI), arterial spin labelling (ASL), diffusion-weighted imaging (DWI), T2-weighted fluid attenuation inversion recovery (FLAIR), T2-weighted (T2w) imaging, and susceptibility weighted imaging (SWI). Participants were scanned repeatedly, up to six times over a maximum period of five years. One participant was also scanned a further three times on sequential days on one scanner. Fifteen derived metrics were computed from the seven different modalities. Reproducibility (coefficient of variation; CoV, across sites) was best for T1w derived grey matter, white matter and hippocampal volume (CoV < 1.5%), compared to rsfMRI and SWI derived metrics (CoV, 19% and 21%). For a given metric, long-term repeatability (CoV across time) was comparable to reproducibility, with short-term repeatability considerably better. Reproducibility and repeatability were assessed for a suite of markers calculated from a dementia MRI protocol. In general, structural markers were less variable than functional MRI markers. Variability over time on the same scanner was comparable to variability measured across different scanners. Overall, the results support the viability of multi-site longitudinal studies for monitoring cognitive decline. [ABSTRACT FROM AUTHOR]

Additive manufacturing, especially powder bed fusion using a laser beam of metals (PB-LB/M), allows the build-up of complex parts. Therefore, PBF-LB/M is already used in multiple fields, such as medical or aerospace industry. To promote the use of AM within the automotive sector materials such as case-hardening steels have been developed for PBF-LB/M to manufacture drivetrain parts e.g. gears. However, the automotive industry requires strict tolerances and repeatability in the manufacturing processes. At first, the repeatability of specimens built with the case-hardening steel 16MnCr5 within one build plate is investigated. Therefore, the dimensional accuracy in x-, y- and z-direction is measured and ISO basic tolerances are derived. Additionally, the density of specimens within one build plate is determined. Both results are linked to the recoating direction and the occurring gas flow. In a second step, the repeatability between subsequent build jobs is analyzed. The tensile strength of specimens manufactured in 12 build jobs of similar layout is investigated showing high repeatability with properties exceeding conventional material. The occurring tolerances of more than 80 Type 1 gears in 20 build jobs are aggregated to evaluate the process capability of the PBF-LB/M process. [ABSTRACT FROM AUTHOR]

Atmospheric plasma spraying (APS) is a widely used thermal spraying process for producing coatings for various applications. The characteristics of the produced coatings is influenced by multiple tens of process parameters and their complex interactions. Even when the same process parameters are used, there is a considerable variability in the characteristics of the produced coatings. The poor repeatability of the coating characteristics can be attributed to process instabilities as well as to relatively large measurement uncertainties of the coating characterization methods. In this study, it was investigated how the particle size distribution (PSD) width affects the repeatability of the coating characteristics between multiple spray runs. It focused on four coating parameters: thickness, porosity, microhardness and deposition efficiency (DE). First, the measurement uncertainties of these parameters were evaluated. Then, the effect of the PSD width on the repeatability of the four coating characteristics was examined by comparing two sets of produced coatings. One set was sprayed using a powder with a wide PSD; while for the other, the powder was sieved to narrower PSD but with the same mean size. All other process parameters were the same for both sets of coatings. The results show that a narrow PSD improves both the coating characteristics while also improving the coating repeatability. [ABSTRACT FROM AUTHOR]

Sensors based on inorganic nanomaterials for the detection of human body fluids show great potential in real-time detection and treatment of human health due to their advantages of small size and easy to wear. Nevertheless, most of the existing sensors have the disadvantage of detecting relatively simple substances and suffer from low sensitivity, which undermines their practical applicability in body fluids detection. In this study, based on the transition metal carbide (Ti 3 C 2 T x , MXene)/αFe 2 O 3 grid composite structure, a highly sensitive flexible sensor is proposed, which can realize accurate and simultaneous detection of glucose and uric acid (UA) concentration. The sensor exhibits outstanding durability, enabling it to withstand prolonged immersion in water and exposure to high flow velocities. More importantly, the sensor has extremely high sensitivity for both glucose (2.14 mA mM−1 cm−2, 5.5 times the mean value) and UA (2.56 μA μM−1 cm−2, 3.5 times the mean value). It also has the advantage of low detection limits (0.27 μM for glucose and 0.31 μM for UA) and a wide linear detection range (1 mM–40 mM for glucose and 10 μM–900 μM for UA) compared to existing sensors for body fluids detection. In addition, the sensor has excellent repeatability, long shelf life (over 40 days) and excellent immunity to interference (accurate detection of glucose and UA in the presence of multiple metal ions as well as organics in human body fluids). This study establishes the groundwork for developing a production-ready and highly sensitive blood detection sensor capable of real-time monitoring. [Display omitted] • Simultaneous detection of glucose and UA based on MXene/αFe 2 O 3 grid composite structure. • Affected by the αFe 2 O 3 nanostructure, the sensor has excellent sensitivity. • The sensitivity is 2.14 mA mM−1 cm−2 for glucose and 2.56 μA μM−1 cm−2 for UA. • Detection range is 1 mM–40 mM (glucose) and 10 μM–900 μM (UA). • The MXene/αFe 2 O 3 sensor demonstrates excellent durability and repeatability. [ABSTRACT FROM AUTHOR]

Many interest point detectors have been designed so far to work in two dimensional (2-D) images. However, expansion of these detectors into the third dimension for three dimensional (3-D) images can refine their representational power. This paper presents how the Harris corner, LoG filtering-based blob, and salient regions detectors can be expanded to find interest points in volumetric images handling multiple slices collectively. Performances of 2-D and 3-D detector implementations were assessed both qualitatively and quantitatively with value combinations of different parameters using metrics such as F1-score, localization error, and repeatability in binary images of twenty 3-D object models from the Princeton Shape Benchmark (PSB). Computation of F1-score and localization error depended on some manually marked ground truth points, while repeatability measurement was according to the proximity of the detected point sets. The 3-D detectors were evaluated as more successful in capturing distinctive and sparse interest points on 3-D object surfaces in qualitative analyses. Despite having greater computational complexities, most of the 3-D detectors yielded better average F1-score, localization accuracy, and repeatability given uniqueness constraint on the matched points in quantitative analyses. Therefore, the 3-D detectors appear preferable when longer working durations or sparser representations would not constitute any disadvantage. [ABSTRACT FROM AUTHOR]

Behavioural reactivity is an expression of temperament that may influence an animal's response to stressful situations and impact on handleability and the human-animal relationship. Shortcomings of previously described tests led to the development of a standardized startle protocol in sheep using a tactile stimulus (airblast to the face) and the presence of conspecifics to minimize the effects of social isolation. Here we tested the repeatability of the protocol, the consistency of the response and habituation to the protocol. Twenty sheep were tested across four startle interval test phases. Phases were applied consecutively such that each sheep received up to 17 startles across a six-week period with two to six days between test phases. Phases were; within – up to 5 startles over a 7 min test, Bi-hourly – four repetitions of a single 4-minute startle test 2 hours apart on one day, daily – a single 4-minute startle test repeated over four consecutive days and, weekly – a single 4-minute startle test repeated once per week over four consecutive weeks. Three measures of startle magnitude, retreat distance (zone 1–6) and startle duration (s), startle force (gs), were recorded for each startle. A reduction in response to the startle stimulus over time was identified; however, consistent responses of sheep for the measures of startle magnitude were generally observed across test phases. Repeatability of retreat distance and startle force were moderate to high within test phases (0.56–0.82), whereas startle duration had low to moderate repeatability (0.26–0.50). Strong consistency in individual responses, good repeatability, and the presence of a distinct startle response after repeated applications of the stimulus indicate that the startle test shows promise as a measure of reactive temperament in sheep. Further development to improve the tests access in commercial environments may also facilitate producers use of startle magnitude for the selection of less reactive temperaments to improve handleability, safety and welfare on farm. [Display omitted] • Sheep habituated to the startle stimulus over time but still showed a response. • Responses between sheep for startle magnitude were generally consistent. • Repeatability of retreat distance and startle force were moderate to high. • Repeatability and individual consistency of startle duration was lower. • The startle test shows promise as a measure of reactive temperament in sheep. [ABSTRACT FROM AUTHOR]

[Display omitted] • We are using AZOD and HDBE as novel modifiers on PLE for the first time. • Modifiers complex with Cd and Pb ions due to electron-donor atoms. • Electrode surfaces were analyzed by EDS, EIS, and CV techniques. • SEM was used to investigate the surface morphology of modified electrodes. • The two sensors can be used to analyze Pb (II) and Cd (II) by CV and SWV. This research introduces a cost-effective and straightforward approach to fabricating two novel electrochemical sensors. The initial novel sensor, termed AZOD/PLE, involves coating the surface of a pencil lead electrode (PLE) with the azo dye molecule (AZOD). The second novel sensor, named HDBE/PLE, is created by coating the pencil lead electrode (PLE) with a newly synthesized novel Schiff base molecule (HDBE), characterized through techniques such as IR, 1H NMR, and 13C NMR. The reason for the choice of the modifier materials in this research is their complexing ability with metal ions since they contain electron donor atoms such as O and N, which can form coordination bonds with the toxic heavy metal's ions, cadmium and lead. This is the first time using the azo dye molecule (AZOD) and the novel Schiff base molecule (HDBE) as modifiers on PLE. The characterization of the electrode surfaces was made by energy-dispersive X-ray spectroscopy (EDS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). The surface morphology of the electrode was investigated by scanning electron microscopy (SEM). CV results indicate that the modified electrodes possess larger electroactive surface areas compared to the bare PLE. Square wave voltammetry (SWV) results demonstrate that both sensors exhibit high sensitivity in detecting low concentrations of Cd (II) and Pb (II) in tris-HCl buffer (0.1 M) for both single-metal and multi-metal solutions. These sensors can be easily produced in a single step and exhibit excellent selectivity, stability, reproducibility, and repeatability, making them well-suited for detecting Pb (II) and Cd (II) in aqueous environments. [ABSTRACT FROM AUTHOR]

Ideally, scientific results are communicated such that they can be critically assessed, discussed, and used for future research by the scientific community. Replication studies that test and also verify earlier results ensure trust in the scientific work and discussion culture. In this note, we illustrate main challenges in replication studies using the example of a recently published replication attempt of a paper entitled 'Terrorism and land use in agriculture: The case of Boko Haram in Nigeria' on the effects of armed conflict on agricultural land use and the corresponding reaction of the authors of the initial research paper. We argue that a comprehensive, transparent description of the data and methods used is just as crucial as the opportunity to objectively, constructively, and fairly discuss criticism during the replication process. From this series of articles, we further derive lessons for replication debates in general by highlighting challenges and possible ways of dealing with strained relations between authors and replicators. Rethinking solutions to ensure supportive collaborations is crucial in shaping the future discourse surrounding replication debates. • Replication studies test and verify earlier results to ensure trust in the scientific work and discussion culture. • A comprehensive, transparent description of the data and methods used is necessary. • The opportunity to objectively, constructively, and fairly discuss criticism during the replication process is crucial. • We highlight challenges in replication debates and suggest ways to avoid strained relations between authors and replicators. [ABSTRACT FROM AUTHOR]

Graphene has evolved from a scientific research subject to an industrial product, in need of a normative basis for its key control characteristics. Recently two new IEC technical specifications that establish standardized procedures for assessing the sheet resistance R S of monolayer graphene have been published. These new standards, part of the IEC TS 62607-6-xx series, outline protocols for employing two contact methods: i) van der Pauw, and ii) in-line four-point probe. In the following we present and discuss illustrative examples of the scientific experiments designed and performed to inform the standardization process behind the presented standards. In particular we report about the investigation of mechanical contacting of chemical-vapor-deposited monolayer graphene and the measurement of the R S in cm2 area graphene samples with non uniform resistivity distributions. This paper includes an overview of the broader IEC context, detailing the key steps in the development of the standards themselves. • Substantial technical input provided by scientific research to documentary standards. • Good practices in research to avoid reproducibility gap in the field of graphene. • Normative needs for innovative materials in electrotechnical applications. [ABSTRACT FROM AUTHOR]

• Heterogeneity in perception and non-repeatability can result in temporal imprecision. • Imprecision can make the interpretation of TDS/CATA curves/difference curves tricky. • Temporal differences within and between products were tested using bootstrap. • Time-variability plots enable to visualize uncertainty in periods of perception. • Differences lasting for less than 10% of total duration can be uncertain/spurious. Temporal Dominance of Sensations (TDS) and Temporal Check-All-That-Apply (TCATA) make it possible to capture temporal changes in the perception of sensory attributes within a product. However, temporal measurements bring new sources of uncontrolled variability that can make them imprecise, particularly with consumer panels. This article aims to demonstrate the importance of considering this imprecision when interpreting temporal data. First, the levels of imprecision due to non-repeatability or disagreement were assessed. The precision of TDS and TCATA was shown to be low, mainly due to disagreement caused by high heterogeneity in total durations of perception. Then, a new framework of analysis has been introduced. It allowed testing of differences in the median times of selection or unselection of attributes. A new representation of TDS and TCATA data has been proposed to visualize and objectify uncertainty in periods of perception. The conclusions obtained with the new framework were compared to those obtained with the usual analyses based on the evolution of citation rates over time. It was shown that the interpretation of TDS/TCATA curves and difference curves can be tricky without guidelines regarding the minimum size of differences that can be considered significant and interpretable. Finally, it was shown that the temporal resolution of the methods was about 10% of the total duration of the perception. These findings question the ability of TDS and TCATA to capture subtle temporal differences. Therefore, recommendations were made for interpreting temporal data in a way that robust conclusions can be drawn. [ABSTRACT FROM AUTHOR]

Reproducibility is widely acknowledged as a fundamental principle in scientific research. Currently, the scientific community grapples with numerous challenges associated with reproducibility, often referred to as the "reproducibility crisis". This crisis permeated numerous scientific disciplines. In this study, we examined the factors in scientific practices that might contribute to this lack of reproducibility. Significant focus is placed on the prevalent integration of computation in research, which can sometimes operates as a black box in published papers. Our study primarily focuses on high-performance computing (HPC), which presents unique reproducibility challenges. This paper provides a comprehensive review of these concerns and potential solutions. Furthermore, we discuss the critical role of reproducible research in advancing science and identifying persisting issues within the field of HPC. [ABSTRACT FROM AUTHOR]

Open-source pulse sequence programs offer an accessible and transparent approach to sequence development and deployment. However, a common framework for testing, documenting, and sharing open-source sequences is still needed to ensure sequence usability and repeatability. We propose and demonstrate such a framework by implementing two sequences, Inversion Recovery Spin Echo (IRSE) and Turbo Spin Echo (TSE), with PyPulseq, and testing them on a commercial 3 T scanner. We used the ACR and ISMRM/NIST phantoms for qualitative imaging and T 1 /T 2 mapping, respectively. The qualitative sequences show good agreement with vendor-provided counterparts (mean Structural Similarity Index Measure (SSIM) = 0.810 for IRSE and 0.826 for TSE). Both sequences passed five out of the seven standard ACR tests, performing at similar levels to vendor counterparts. Compared to reference values, the coefficient of determination R2 was 0.9946 for IRSE T 1 mapping and 0.9331 for TSE T 2 mapping. All sequences passed the scanner safety check for a 70 kg, 175 cm subject. The framework was demonstrated by packaging the sequences and sharing them on GitHub with data and documentation on the file generation, acquisition, reconstruction, and post-processing steps. The same sequences were tested at a second site using a 1.5 T scanner with the information shared. PDF templates for both sequence developers and users were created and filled. • A framework for validating and sharing open-source MR pulse sequences was proposed. • Two fundamental sequences in the Pulseq format demonstrate framework usage. • Two sites, one at 3 T and one at 1.5 T, successfully tested the same sequence files. • Safety, image quality, and T 1 /T 2 mapping accuracy metrics were evaluated. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: A critical performance metric for any quantitative imaging biomarker is its ability to reliably generate similar values on repeat testing. This is known as the repeatability of the biomarker, and it is used to determine the minimum detectable change needed in order to show that a change over time is real change and not just due to measurement error. Test-retest studies are the classic approach for estimating repeatability; however, these studies can be infeasible when the imaging is expensive, time-consuming, invasive, or requires contrast agents. The objective of this study was to develop and test a method for estimating repeatability without a test-retest study.Materials and Methods: We present a statistical method for estimating repeatability and testing whether an imaging method meets a specified criterion for repeatability in the absence of a test-retest study. The new method is applicable for the particular situation where a reference standard is available. A Monte Carlo simulation study was conducted to evaluate the performance of the new method.Results: The proposed estimator is unbiased, and hypothesis tests with the new estimator have nominal type I error rate and power similar to a test-retest study. We considered the situation where the reference standard provides the true value, as well as when the reference standard itself has various magnitudes of measurement error. An example from CT imaging biomarkers of atherosclerosis illustrates the new method.Conclusion: Precision of a QIB can be measured without a test-retest study in the situation where a reference standard is available. [ABSTRACT FROM AUTHOR]

Research Question: What is the intra- and inter-assessor error of the Oxford Foot Model (OFM) during healthy adult walking when applied by three assessors with different professional backgrounds and lower limb marker placement experience, not native to the originators of the model and with no prior clinical experience of the model?Background: No previous OFM studies have examined the repeatability of more than two assessors with different backgrounds, and many of the studies have been conducted by the model originators METHODS: The OFM was applied to ten healthy adults on three separate occasions by three different assessors with varied professional experience and no prior involvement with the OFM (other than local training). Participants walked at self-selected speeds and intra/inter assessor error was calculated using the SEM + 95% upper confidence limit.Results: Inter-assessor errors ranged from 2.2° to 5.5° whereas intra-assessor errors fell between 1.8° and 5.5°. The error difference between assessors over the same joint angle varied from 0.4° (hindfoot/tibia dorsiflexion) to 1.5° (hindfoot/tibia inversion). The percentage of error to total range of motion varied from 11% (hindfoot/tibia dorsiflexion) to 126% (forefoot/hindfoot adduction).Significance: Based on commonly used recommendations, the OFM is a largely repeatable tool for measuring foot kinematics during healthy adult walking when applied by assessors with no prior OFM experience, varied experience and not native to the model originators. Intra-assessor error was lower for assessors with prior anatomical knowledge and significant lower limb marker placement experience. The proportion of inter-assessor error to movement exceeded 50% of the total range of motion for four movements, notably forefoot/hindfoot adduction (126%). As such, this movement cannot be recommended as an outcome measure. Inter- and intra-assessor error, specific to each laboratory, should be considered, along with the proportion of error to range of motion when interpreting patient data. [ABSTRACT FROM AUTHOR]

The present work seeks to develop a novel and systematic approach to quantifying the repeatability of textured surfaces, a relevant property for several technological fields. Specifically, aluminum alloy and stainless steel specimens were subject to nanosecond pulsed laser texturing to produce arrays of ablation craters in a typical configuration employed to improve wettability and tribological performance. Feature repeatability was firstly assessed in terms of crater volume and interfacial area, after which an additional parameter was developed based on the Pearson's Correlation Coefficient (PCC). Within the tested laser parameter range, the crater volume exhibited highest repeatability in the high energy dose regime on aluminum alloy specimens, while the crater volume was more repeatable in the low energy dose regime on stainless steel specimens. This difference was attributed to the development of an oxide ring surrounding the craters on stainless steel at high energy dose. This outcome was confirmed through analysis of the point-to-point repeatability, where process repeatability was determined for different portions of the ablation craters. • Surface metrology provides useful tools to study the process repeatability. • Repeatability of laser processed craters depends on the energy dose irradiated. • Surface height, area and void volume may have different repeatability. • Process surface repeatability varies point-to-point within the same processed area. [ABSTRACT FROM AUTHOR]

The aim of the study was to test the reproducibility of performing conventional point shear wave elastography (pSWE), auto-pSWE, and ultrasound derived fat fraction (UDFF) in adult livers. The Institutional Review Board approved the study and all participants provided written informed consent. Conventional pSWE (obtaining 10 measurements through 10 acquisitions), auto-pSWE (automatically obtaining 15 measurements by a single acquisition), and UDFF (one measurement obtained by one acquisition) of the liver were prospectively performed in 21 participants (10 men, 11 women, mean age 63y) by senior and junior operators in February-May 2021. Shear wave velocity (SWV, m/s) of the liver was measured by conventional pSWE and auto-pSWE. Intraclass correlation coefficient (ICC) and Bland-Altman limits of agreement were used to test intra-observer repeatability and inter-observer reproducibility in measuring pSWE, auto-pSWE, and UDFF. ICC for testing intra-observer repeatability and inter-observer reproducibility in performing pSWE, auto-pSWE, and UDFF was >0.85 (95% confidence interval 0.85-0.99). The mean difference of 95% Bland-Altman limits of agreement was -0.02 (upper 0.09, lower -0.12) and the correlation of SWV measured between conventional pSWE and auto-pSWE methods was strong (r2 = 0.87). Our results suggest good repeatability and reproducibility in measuring UDFF and SWV in adult livers. The auto-pSWE has higher reliability, reproducibility and time efficacy in measuring SWV of adult livers when compared to conventional pSWE method. • List reliability in performing liver ultrasound derived fat fraction (UDFF) • List the comparison between conventional pSWE and newly developed auto-pSWE • Demonstrating a good reproducibility of newly developed UDFF and auto-pSWE in adult livers [ABSTRACT FROM AUTHOR]

Background: Myocardial flow reserve (MFR) assessment with cardiac positron emission computed tomography (PET/CT) is well established, and quantification relies on commercial software packages. However, for reliable use, repeatability and reproducibility are important. The aim of this study was therefore to investigate and compare between scans and software packages the repeatability and reproducibility of 82Rb-PET/CT estimated MFR. Methods and Results: Forty healthy volunteers completed two 82Rb-PET/CT rest and adenosine stress scans. syngo.MBF (Siemens), quantitative-gated SPECT (QGS) (Cedars-Sinai), and Corridor4DM (4DM) were used for analyses. Motion correction was available for 4DM. Fifty percent were men and age was 24 ± 4 years (mean ± SD). Repeatability of MFR varied between scans. syngo.MBF: mean difference (95% CI) 0.26 (− 0.03 to 0.54), P = 0.07, limits of agreement (LoA): − 1.43 to 1.95; QGS: 0.19 (− 0.08 to 0.46), P = 0.15, LoA: − 1.38 to 1.76; 4DM: 0.08 (− 0.17 to 0.34), P = 0.50, LoA: − 1.37 to 1.53; and 4DM motion corrected: 0.17 (− 0.17 to 0.51), P = 0.32, LoA: − 1.89 to 2.22. MFR was higher using 4DM +/− motion correction compared with syngo.MBF and QGS (all P < 0.0001). Concordance between syngo.MBF and QGS was high (P = 0.83). Conclusions: Reproducibility of MFR varied for the different software. The highest concordance between MFRs was found between syngo.MBF and QGS. [ABSTRACT FROM AUTHOR]

Background: The aim of this work was to assess the robustness of cardiac SPECT radiomic features against changes in imaging settings, including acquisition, and reconstruction parameters. Methods: Four commercial SPECT and SPECT/CT cameras were used to acquire images of a static cardiac phantom mimicking typical myorcardial perfusion imaging using 185 MBq of 99mTc. The effects of different image acquisition and reconstruction parameters, including number of views, view matrix size, attenuation correction, as well as image reconstruction related parameters (algorithm, number of iterations, number of subsets, type of post-reconstruction filter, and its associated parameters, including filter order and cut-off frequency) were studied. In total, 5,063 transverse views were reconstructed by varying the aforementioned factors. Eighty-seven radiomic features including first-, second-, and high-order textures were extracted from these images. To assess reproducibility and repeatability, the coefficient of variation (COV), as a widely adopted metric, was measured for each of the radiomic features over the different imaging settings. Results: The Inverse Difference Moment Normalized (IDMN) and Inverse Difference Normalized (IDN) features from the Gray Level Co-occurrence Matrix (GLCM), Run Percentage (RP) from the Gray Level Co-occurrence Matrix (GLRLM), Zone Entropy (ZE) from the Gray Level Size Zone Matrix (GLSZM), and Dependence Entropy (DE) from the Gray Level Dependence Matrix (GLDM) feature sets were the only features that exhibited high reproducibility (COV ≤ 5%) against changes in all imaging settings. In addition, Large Area Low Gray Level Emphasis (LALGLE), Small Area Low Gray Level Emphasis (SALGLE) and Low Gray Level Zone Emphasis (LGLZE) from GLSZM, and Small Dependence Low Gray Level Emphasis (SDLGLE) from GLDM feature sets turned out to be less reproducible (COV > 20%) against changes in imaging settings. The GLRLM (31.88%) and GLDM feature set (54.2%) had the highest (COV < 5%) and lowest (COV > 20%) number of the reproducible features, respectively. Matrix size had the largest impact on feature variability as most of the features were not repeatable when matrix size was modified with 82.8% of them having a COV > 20%. Conclusion: The repeatability and reproducibility of SPECT/CT cardiac radiomic features under different imaging settings is feature-dependent. Different image acquisition and reconstruction protocols have variable effects on radiomic features. The radiomic features exhibiting low COV are potential candidates for future clinical studies. [ABSTRACT FROM AUTHOR]

Our purpose is to evaluate bias and repeatability of the quantitative MRI sequences QRAPMASTER, based on steady-state imaging, and variable Flip Angle MRF (MRF-VFA), based on the transient response. Both techniques are assessed with a standardized phantom and five volunteers on 1.5 T and 3 T clinical scanners. All scans were repeated eight times in consecutive weeks. In the phantom, the mean bias±95% confidence interval for T1 values with QRAPMASTER was 10 ± 10% on 1.5 T and 4 ± 13% on 3.0 T. The mean bias for T1 values with MRF-vFA was 21 ± 17% on 1.5 T and 9 ± 9% on 3.0 T. For T2 values the mean bias with QRAPMASTER was 12 ± 3% on 1.5 T and 23 ± 1% on 3.0 T. For T2 values the mean bias with MRF-vFA was 17 ± 1% on 1.5 T and 19 ± 2% on 3.0 T. QRAPMASTER estimated lower T1 and T2 values than MRF-vFA. Repeatability was good with low coefficients of variation (CoV). Mean CoV ± 95% confidence interval for T1 were 3.2 ± 0.4% on 1.5 T and 4.5 ± 0.8% on 3.0 T with QRAPMASTER and 2.7% ± 0.2% on 1.5 T and 2.5 ± 0.2% on 3.0 T with MRF-vFA. For T2 were 3.3 ± 1.9% on 1.5 T and 3.2 ± 0.6% on 3.0 T with QRAPMASTER and 2.0 ± 0.4% on 1.5 T and 5.7 ± 1.0% on 3.0 T with MRF-vFA. The in-vivo T1 and T2 are in the range of values previously reported by other authors. The in-vivo mean CoV ± 95% confidence interval in gray matter were for T1 1.7 ± 0.2% using QRAPMASTER and 0.7 ± 0.5% using MRF-vFA and for T2 were 0.9 ± 0.4% using QRAPMASTER and 2.4 ± 0.5% using MRF-vFA. In white matter were for T1 0.9 ± 0.3% using QRAPMASTER and 1.3 ± 1.1% using MRF-vFA and for T2 were 0.7 ± 0.4% using QRAPMASTER and 2.4 ± 0.4% using MRF-vFA. A GLM analysis showed that the variations in T1 and T2 mainly depend on the field strength and the subject, but not on the follow-up repetition in different days. This confirms the high repeatability of QRAPMASTER and MRF-vFA. In summary, QRAPMASTER and MRF-vFA on both systems were highly repeatable with moderate accuracy, providing results comparable to standard references. While repeatability was similar for both methods, QRAPMASTER was more accurate. QRAPMASTER is a tested commercial product but MRF-vFA is 4.77 times faster, which would ease the inclusion of quantitative relaxometry. [ABSTRACT FROM AUTHOR]