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For numerous activities in or with soils, information on the abrasiveness of the soil is required, as this is an important parameter for the economic efficiency of a construction project. To determine the abrasiveness of loose soil, the LCPC test is carried out in accordance with the French standard NF P 18-579. In this test, a test wing rotates for five minutes in a soil sample with a grain size between 4.0 mm and 6.3 mm. The mass loss is determined, from which the ABR value is calculated. The test wings used for the tests must have defined material properties so as not to falsify the abrasiveness results. This article presents material characterization of test wings from different test series using the LCPC test. In contrast to the French standard, the test wings are not only examined with regard to their mass loss, but their hardness is measured and a metallographic characterization of the metal microstructure is also carried out. In the tests, the grain fraction, the test duration and the fraction of broken grains in the soil sample were specifically varied. On the one hand, the metallographic investigations support and confirm the geotechnical results, on the other hand, they provide important insights into the wear of the test wings in the LCPC test. In the series of tests with a grain fraction that deviated from the standard, the influence of different grain sizes on the metal structure was also clearly demonstrated. The progression of wear on the test wings over time can be visualised in the tests with different test times. In addition, differences in the microstructure and surface properties of test wings, which can affect the resulting ABR values, were identified and analysed. Recommendations for the manufacturing of the test wings for the standardised LCPC test are derived.

Water is an essential nutrient, but the effect it has on performance generally receives little attention. There are few systems and guidelines for collection of water intake (WI) phenotypes in beef cattle, which makes large-scale research on WI a challenge. The Beef Improvement Federation has established guidelines for feed intake (FI) and ADG tests, but no guidelines exist for WI. The goal of this study was to determine the test duration necessary for collection of accurate WI phenotypes. To facilitate this goal, individual daily WI and FI records were collected on 578 crossbred steers for a total of 70 d using an Insentec system at the Oklahoma State University Willard Sparks Beef Research Unit. Steers were fed in five groups and were individually weighed every 14 d. Within each group, steers were blocked by BW (low and high) and randomly assigned to one of four pens containing approximately 30 steers per pen. Each pen provided 103.0 m2 of shade and included an Insentec system containing six feed bunks and one water bunk. Steers were fed a constant diet across groups and DMI was calculated using the average of weekly percent DM within group. Average FI and WI for each animal were computed for increasingly large test durations (7, 14, 21, 28, 35, 42, 49, 56, 63, and 70 d), and ADG was calculated using a regression formed from BW taken every 14 d (0, 14, 28, 42, 56, and 70 d). Intervals for all traits were computed starting from both the beginning (day 0) and the end of the testing period (day 70). Pearson and Spearman correlations were computed for phenotypes from each shortened test period and for the full 70-d test. Minimum test duration was determined when the Pearson correlations were greater than 0.95 for each trait. Our results indicated that minimum test duration for WI, DMI, and ADG were 35, 42, and 70 d, respectively. No comparable studies exist for WI; however, our results for FI and ADG are consistent with those in the literature. Although further testing in other populations of cattle and areas of the country should take place, our results suggest that WI phenotypes can be collected concurrently with DMI, without extending test duration, even if following procedures for decoupled intake and gain tests.

Background Balance parameters derived from wearable sensor measurements during postural sway have been shown to be sensitive to experimental variables such as test duration, sensor number, and sensor location that influence the magnitude and frequency-related properties of measured center-of-mass (COM) and center-of-pressure (COP) excursions. In this study, we investigated the effects of test duration, the number of sensors, and sensor location on the reliability of standing balance parameters derived using body-mounted accelerometers. Methods Twelve volunteers without any prior history of balance disorders were enrolled in the study. They were asked to perform two 2-min quiet standing tests with two different testing conditions (eyes open and eyes closed). Five inertial measurement units (IMUs) were employed to capture postural sway data from each participant. IMUs were attached to the participants’ right legs, the second sacral vertebra, sternum, and the left mastoid processes. Balance parameters of interest were calculated for the single head, sternum, and sacrum accelerometers, as well as, a three-sensor combination (leg, sacrum, and sternum). Accelerometer data were used to estimate COP-based and COM-based balance parameters during quiet standing. To examine the effect of test duration and sensor location, each 120-s recording from different sensor locations was segmented into 20-, 30-, 40-, 50-, 60-, 70-, 80-, 90-, 100-, and 110-s intervals. For each of these time intervals, time- and frequency-domain balance parameters were calculated for all sensor locations. Results Most COM-based and COP-based balance parameters could be derived reliably for clinical applications (Intraclass-Correlation Coefficient, ICC ≥ 0.90) with a minimum test duration of 70 and 110 s, respectively. The exceptions were COP-based parameters obtained using a sacrum-mounted sensor, especially in the eyes-closed condition, which could not be reliably used for clinical applications even with a 120-s test duration. Conclusions Most standing balance parameters can be reliably measured using a single head- or sternum-mounted sensor within a 120-s test duration. For other sensor locations, the minimum test duration may be longer and may depend on the specific test conditions.

Pearson Test of English Academic (PTE Academic), a high-stakes English language proficiency test, underwent substantial revisions in 2021. The test duration was reduced from 3 h to 2 h by reducing specific task numbers and sections. This study investigates the impact of these changes on teachers’ perceptions and teaching practices, areas previously underexplored in language assessment literature. It focuses on the implications of the test’s modifications, examining the face validity and washback effects through the lens of teachers in mainland China. Semi-structured interviews with four experienced PTE Academic test trainers, who were familiar with both the original and revised test formats, reveals that the revised PTE Academic is perceived to maintain strong face validity, particularly noted in its academic authenticity, balanced skill structure, and perceived result accuracy. Additionally, most teachers perceived an increase in test difficulty. A mixed washback effect was observed: while improvements in students’ language competence—a positive outcome—were noted, teachers also reported a continued reliance on teaching test-oriented strategies for higher-scoring tasks, indicating negative washback. This study highlights the significant implications of reducing PTE Academic’s duration and offers targeted recommendations for its future improvement. These suggestions aim to enhance students’ academic language skills, thereby better aligning PTE Academic with the practical language abilities required in university settings.

This paper presents an alternating testing strategy to improve the reliability of multi-state safety instrumented systems (SISs) under degradation conditions. A dynamic Bayesian network (DBN) model is developed to assess SIS unavailability, integrating proof-testing parameters and capturing multi-state component behavior. Applied initially to the actuator layer of a SIS with a 1oo3 (one-out-of-three) redundancy structure, the study examines the impact of extended test durations, showing that the alternating strategy reduces non-zero test durations compared to the simultaneous test strategy. The approach is then extended to a complete SIS, with a case study demonstrating its potential to enhance system reliability and optimize maintenance management by considering degradation and redundancy factors.

Purpose Early diagnosis of ICU-acquired weakness can support the ICU team in applying appropriate interventions which may lead to better results at clinical and functional outcomes. Thus, interest has increased in non-invasive and more feasible methods to diagnose neuromuscular dysfunction, such as the stimulus electrodiagnosis test (SET) and strength-duration test (SDT). The aim of the present study was to assess the agreement of the SET and SDT carried out automatically using an innovative method. Methods We performed a prospective observational study to determine the agreement of SET and SDT, performed automatically using a biofeedback circuit to detect muscle contractions, comprised of an accelerometer module connected to an electrical stimulator. These tests were applied in healthy and critically ill participants. Results Twenty-one participants were analyzed in the study, and 168 assessments of SET and SDT were performed. The Bland-Altman analysis of automatic SET and SDT in the control group showed a low bias of −25 (95% CI, −94.3 to 44.3 μs) and 0.6 (95% CI, −1.9 to 3.1 μC) respectively. In the critically ill group, automatic SET and SDT presented a low bias of −104.5 (95% CI, −1716 to 1507μs) and −12.6 (95% CI, −119.4 to 94.1 μC) respectively. Conclusions We demonstrated that an innovative method to carry out SET and SDT automatically presents low agreement bias and good to excellent reliability.

Experiments on a two-phase rotating detonation combustor operating with gasoline and high total temperature air were conducted to investigate the initiation characteristics, operation mode, and propagation characteristics of a two-phase rotating detonation wave (RDW). The outer diameter, inner diameter, and length of the annular combustor were 204 mm, 166 mm, and 155 mm, respectively. The initiation characteristics, operation mode, and propagation characteristics of the two-phase RDW were studied by varying the total air temperature. The experimental results show that the initiation time of the RDW first decreases and then increases with an increase in the total air temperature and reaches an extreme value at a total air temperature of 713 K. Four operation modes (failure, intermittent detonation, single wave, coexistence of double wave collision, and single wave) of the detonation combustor were found for different total air temperatures. The effect of the total air temperature on the peak pressure stability and propagation frequency of the RDW was studied in detail. From the results, the effect of the equivalence ratio on the working characteristics of a rotating detonation engine (RDE) was investigated at a total air temperature of 713 K. Four detonation propagation modes (sporadic detonation, intermittent detonation, single-wave mode, coexistence of double-wave collision and single wave) were obtained in the combustor. When the equivalence ratio was 0.52, the detonation initiation failed. The pressure characteristics in the combustor and propagation frequency of the RDW were studied with different equivalence ratios. In addition, a long-duration test was performed for 3 s to verify the continuous working feasibility of the two-phase RDE.

Due to the well-defined role of β-alanine as a substrate of carnosine (a major contributor to H + buffering during high-intensity exercise), β-alanine is fast becoming a popular ergogenic aid to sports performance. There have been several recent qualitative review articles published on the topic, and here we present a preliminary quantitative review of the literature through a meta-analysis. A comprehensive search of the literature was employed to identify all studies suitable for inclusion in the analysis; strict exclusion criteria were also applied. Fifteen published manuscripts were included in the analysis, which reported the results of 57 measures within 23 exercise tests, using 18 supplementation regimes and a total of 360 participants [174, β-alanine supplementation group (BA) and 186, placebo supplementation group (Pla)]. BA improved ( P  = 0.002) the outcome of exercise measures to a greater extent than Pla [median effect size (IQR): BA 0.374 (0.140–0.747), Pla 0.108 (−0.019 to 0.487)]. Some of that effect might be explained by the improvement ( P  = 0.013) in exercise capacity with BA compared to Pla; no improvement was seen for exercise performance ( P  = 0.204). In line with the purported mechanisms for an ergogenic effect of β-alanine supplementation, exercise lasting 60–240 s was improved ( P  = 0.001) in BA compared to Pla, as was exercise of >240 s ( P  = 0.046). In contrast, there was no benefit of β-alanine on exercise lasting <60 s ( P  = 0.312). The median effect of β-alanine supplementation is a 2.85% (−0.37 to 10.49%) improvement in the outcome of an exercise measure, when a median total of 179 g of β-alanine is supplemented.

The aim of this study was to determine the shortest test duration necessary for the evaluation of feed efficiency traits, i.e., dry matter intake (DMI), average daily gain (ADG), mid-test metabolic body weight, residual feed intake (RFI), feed conversion ratio (DMI/ADG), and feed conversion efficiency (ADG/DMI). A total of 313 Nellore bulls with an initial age of 283 ± 23.6 days were evaluated by automated feed intake measurement. The tests were divided into six durations (15, 29, 43, 57, 71, and 84 days), with at least one body weight recording at the beginning and one at the end of each period. Residual variances were estimated per period and correlation coefficients (Pearson and Spearman) were calculated between the 5 test durations and the 84-day test. The results indicated a minimum test duration of 15 days (two weight recordings without fasting) for the measurement of mid-test metabolic body weight, a minimum of 43 days for automated DMI measurement, and a minimum of 71 days for the determination of ADG, RFI, feed conversion ratio, and feed conversion efficiency. Individual analysis of the DMI records obtained with the GrowSafe® and Intergado® automated feeders showed that a test duration of 57 days is sufficient for measurement of this trait. We therefore recommend a test duration of 71 days after a minimum adaptation period of 21 days for the determination of feed efficiency in growing Nellore cattle, with weight recordings without fasting every 15 days.

This study was conducted to determine the optimum test duration and the effect of missing data on accuracy of measuring feed efficiency and its 4 related traits ADG, DMI, feed conversion ratio, and residual feed intake in beef cattle using data from 456 steers with 5,397 weekly averaged feed intakes and BW repeated measurements taken over 91 d. Data were collected using the GrowSafe System at the University of Alberta Kinsella Research Station. The changes and relative changes in phenotypic residual variances and correlations (Pearson and Spearman) among data from shortened test durations (7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, or 84 d) and a 91-d test were used to determine the optimum test duration for the 4 traits. The traits were fitted to a mixed model with repeated measures using SAS. Test durations for ADG, DMI, feed conversion ratio, and residual feed intake could be shortened to 63, 35, 42, and 63 d, respectively, without significantly reducing the accuracy of the tests when BW was measured weekly. The accuracy of the test was not compromised when up to 30% of the records were randomly removed after the first 35 d on test. These results have valuable and practical implications for performance and feed efficiency testing in beef cattle.