Total Test Duration Research Articles

Visual tests, touch responses: Computer-based neuropsychological tools

Objective: Investigate three new computer tests of visual abilities relative to traditional paper-and-pencil (P&P) tests on groups with and without cerebral neurological impairment (CNI, Non-CNI) based on MRI and EEG criteria. The new tests employ an intuitive interface with audio instructions, touch responses, non-response prompts, and videography of test behavior. The Presidents Test was designed as an achievement-related measure of visual knowledge; the Railroad Test – visual perception and delayed recognition; and the Swamp Test – visual attention. Attitudes toward testing were assessed with an original Testing Experience Questionnaire (TEQ). Method: Of the 129 participants, 84 were women, 73 identified as non-White, average age 45.5 and education 14.3 years. Procedures included the new computer tests and a selection of standard neuropsychological measures including performance validity tests (PVT). Participants who failed two or three PVTs or had missing PVT data were excluded from main analyses, resulting in N = 115. Results: The new computer tests demonstrated adequate reliability. Correlations and factor analyses confirmed the computer tests as functioning in accordance with design. The Presidents Test was associated with academic achievement. The Railroad and Swamp Tests were linked to visual perception and visual attention. Correlations between computer total test duration time and traditional speed of processing tasks were modest. Computer and traditional tests demonstrated similar discriminability between CNI and Non-CNI groups. TEQ indicated positive attitudes toward testing in general, and computer testing in particular. Conclusions: The new computer tests evaluated in this study were found to be reliable, functioned to assess the designed cognitive domains, and discriminated between CNI and Non-CNI participants similarly to the traditional neuropsychological measures. Attitudes toward computer testing were favorable.

Adding Gusts to a Mobile Wind Tunnel: Experimental Setup and Effect of Simulated Gusts on Horizontal Transport

Wind erosivity has an intermittent character due to complicated interactions between air streams, surface characteristics, and sediment particles. To experimentally investigate the effect of a sudden and local gust on sediment entrainment, a simple setup was installed in a mobile wind tunnel. One, three, and five consecutive gusts were applied and compared with standard test conditions with steady wind. The applied wind was characterized by total test duration (s), duration of gust (s), mean velocity, peak velocity (m s−1), gust factor, and transport capacity based on sediment-specific threshold velocity. The eroded material was collected by sediment containers. The results suggest that 1. the application of gusts inside the mobile wind tunnel setup is feasible but related to uncertainty concerning the applied wind conditions, and 2. the horizontal transport rate increased with the number of applied gusts. While the highest rates were measured during five gusts on sand, the relative effect of gusts was most accentuated in the comparison of one gust to no gust on loam. The findings highlight how temporally and spatially limited gust impact causes extreme particle entrainment. These particles may subsequently either start erosion or enter vertical dust transport.

Field Sprayer with Application Rate Control Using Fast Response Proportional Valves under Variable Speed Conditions

In modern agriculture, which is characterised by dynamic field environments, challenges are faced in maintaining consistent application rates due to varying tractor speeds, field conditions, and certain calibration errors. Conventional control systems, which rely on slower valves, have difficulty adapting to these dynamic field conditions. By contrast, the integration of fast-acting proportional valves improves the precision and flexibility of flow rate adjustment during spraying applications. This research focused on evaluating the accuracy of spraying applications under different tractor speed conditions through field experiments and data analysis. This study involves a field sprayer with boom wings divided into right and left sections, where the flow rate of the liquid to each section is controlled by proportional valves with a 3 s full opening and closing time, dependent on speed information. Using a closed-loop control system consisting of a flow meter, proportional valve, and PLC, the valves are controlled by the PLC’s internal PID blocks. Observations reveal that as the tractor speed increases to a certain level, the system effectively adjusts the application rate close to the target value and maintains control against the changing ground speed during all field tests. The study included five different application tests, with target application rates of 100, 150, 200, 250, and 300 L ha−1, with each repeated three times, resulting in a total of 15 field tests at different ground speeds. During these tests, the data were meticulously recorded every second, covering the tractor speed, flow rate, and pressure values for both right and left boom sections, along with regulator pressure, proportional valve opening rates, and application rates. The durations for each application rate were documented alongside instances within specified periods where error boundaries of ±10% were exceeded. During the total test duration of 9734 s, the actual application rate value exceeded error boundaries during only 209 s. Within the application durations, the speed variation intervals ranged from 5.10 to 10.23 km h−1, 4.64 to 9.91 km h−1, 3.68 to 7.89 km h−1, 4.80 to 8.21 km h−1, and from 4.90 to 8.69 km h−1. The absolute percentage mean application errors were recorded as 2.81%, 2.68%, 2.28%, 2.14%, and 2.51% for respective application rates. Furthermore, statistically significant correlations (p < 0.01) were identified among the variables (speed, valve opening rate, flow rate, pressure) in both the right and left boom sections across all application rates.

Normalized stability time analysis within the boundaries between adults with and without fear of falling

BackgroundThe unilateral stance test, measured by the center of pressure (COP), has been widely used to identify balance deficits. However, there is a critical gap in understanding the specific COP thresholds on postural stability in adults with a fear of falling (FOF).AimsTo investigate the normalized stability time, which was defined as the ratio of time spent within stability boundaries to the total test duration, under different visual conditions and specific thresholds between adults with and without FOF.MethodsTwenty-one older adults with FOF and 22 control subjects completed the unilateral limb standing test in eyes-open and eyes-closed conditions. Normalized stability times were computed based on five pre-determined COP sway range thresholds: 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm.ResultsReceiver operating characteristic analysis determined the diagnostic accuracy of FOF. There were significant differences in the effects of both visual conditions (F = 46.88, p = 0.001) and threshold settings (F = 119.38, p = 0.001) on stability time between groups. The FOF group significantly reduced normalized stability time at the 10 mm COP threshold under eyes-closed conditions (t = – 1.95, p = 0.03).DiscussionThe findings highlight the heightened sensitivity of the 10 mm COP threshold in identifying group variances in postural stability when eyes are closed. Moreover, the FOF group displayed a marked reduction in stability duration based on visual scenarios and normalized thresholds.ConclusionThe study highlights the need to account for both COP boundaries and visual conditions in adults with FOF. When assessing postural control during unilateral stances, clinicians must also give attention to non-visual cues.

Preliminary evaluation of the digital maze test in relation to neuropsychological tests and AD biomarkers

AbstractBackgroundDigital cognitive tools may provide unique opportunities to detect subtle changes in preclinical Alzheimer’s disease (AD). Here, a maze test using a digital pen was evaluated in relation to AD pathological changes measured by amyloid‐β and tau burden.Method172 participants (CN = 161, MCI = 6, dementia = 5) completed the digital maze test, which included multiple “no‐choice” (NC; i.e., no decisions required to complete maze) or “choice” (CH) conditions (i.e., problem‐solving required to complete maze). Maze composite scores were calculated using the total test duration, total number of strokes, and total pen‐off‐page time for the NC and CH conditions separately. Global amyloid‐β PET was quantified with [11C]Pittsburgh‐Compound‐B (PiB) in available participants (n = 171). Entorhinal and inferior temporal tau were quantified with [18F]Flortaucipir (FTP) in available participants (n = 135). Participants completed a battery of traditional neuropsychological tests, with domain factor scores calculated for Executive Functioning (EF), Processing Speed (PS), and Memory (Mem). The associations between maze composite scores, global amyloid‐β, entorhinal tau, and inferior temporal tau were evaluated in separate linear regression models for both the total sample and CN only, correcting for age and education.ResultIn the total sample, CH‐ and NC‐composites were moderately correlated with PS and EF factor scores (r’s = .41‐.46) and less so with Mem factor scores (r’s = 0.2‐0.35). In the total sample, higher PiB was significantly associated with worse performance in NC‐composite (β = 0.543, SE = 0.249, p <.05), but not for CH‐composite (β = 0.467, SE = 0.259, p = .07). Similar results were observed in the CN only sample (NC‐composite: β = 0.468, SE = 0.237, p <.05; CH‐composite: β = 0.469, SE = 0.278, p = .09). PiB was not associated with EF or PS factor scores in the total sample or CN only. Entorhinal and inferior temporal tau were not significantly associated with any maze composites.ConclusionIn a largely cognitively normal sample, performance on the digital maze test was associated with global amyloid‐β burden, particularly in the no‐choice condition, but not with tau. Digitally captured, nuanced performance in EF and PS may be related to early amyloid‐β pathology, but less so with downstream effects of tau.

The shortened version of a web‐based cognitive test tool, cCOG, retains good accuracy in detecting mild cognitive impairment and dementia

AbstractBackgroundcCOG, a web‐based cognitive test tool, has been shown to detect mild cognitive impairment (MCI) and dementia accurately. However, the test now takes approximately 25 minutes to complete, which could be burdensome for patients, especially with cognitive impairment. We assumed that shortening certain subtasks leads to a decrease in total test duration and therefore increases the user‐friendliness of cCOG. In this study, we examined whether shortening these subtasks influences the discriminative value of cCOG.MethodFrom the PredictND and Amsterdam Dementia Cohort (ADC) cohort, we included cCOG results of 424 participants (n = 234 cognitively normal (CN), n = 84 MCI, n = 106 dementia) who were on average 70±9 years and 54% were female. cCOG consists of five subtasks: episodic memory learning, reaction time, modified trail‐making A and B and episodic memory recall. Scores for all subtasks except episodic memory recall were abbreviated into shorter versions, e.g. by cutting the number of items/trials. A global cognitive score (GCS) was computed using a linear regression model based on scores of all subtasks for both the original as the short version. To investigate the diagnostic accuracy of both versions, we calculated pairwise area under the curve (AUC) comparisons for differentiating MCI and dementia from CN.ResultShortening of subtasks led to an average decrease of 4.7 minutes of the total test time (20.1%) for the PredictND cohort (n = 314), with even 5.7 minutes decrease in the dementia group (Figure 1). The accuracy of the GCS based on the short version for differentiating MCI from CN was lower than based on the original version though still considered excellent (AUC = 0.87 [0.83‐0.92] original; AUC = 0.86 [0.81‐0.90] short; Figure 2). For differentiating dementia from CN, the short version performed comparable to the original version (AUC = 0.93 [0.89‐0.96] original; AUC = 0.92 [0.88‐0.96] short; Figure 3).ConclusionShortening subtasks decreased the test duration of cCOG with approximately 5 minutes, while the diagnostic accuracy was preserved. An additional pilot study is needed to test the effect of shortening subtasks on episodic memory recall and global cognitive score. Further development of a user‐friendly and accurate web‐based cognitive test tool is crucial to keep dementia care accessible and affordable.

A new line method; A direct test in spinal muscular atrophy screening for DBS.

Nucleic acid-based assays provide an opportunity to screen for genetically encoded diseases like spinal muscular atrophy (SMA), before the onset of symptoms. Nowadays, such assays could be easily utilized as high-throughputs in SMA to detect a homozygous deletion of exon 7 of the survival motor neuron 1 gene (SMN1) that is responsible for >95% of SMA patients. We developed a new line method (NLM) as a direct real time PCR test procedure without nucleic acid extraction in dried blood spots (DBS) to screen for homozygous deletion of exon 7 of the SMN1 gene. Performance of this setup was evaluated on 580 DBS newborn samples and air dried 50 DBS from whole blood including 20 samples for homozygous deletion of the SMN1 gene detected earlier with MLPA. We found all 580 newborn DBS samples as wild type. DBS prepared from 50 whole blood samples also including 20 affected people were correctly identified as homozygous deletions and 30 wild types of exon 7 of SMN1 as before with MLPA. When the MLPA method was taken as the gold standard, the sensitivity and specificity of the NLM test were found 100% for the detection of SMN1 exon 7 homozygous deletion. In the NLM, the total test duration has been reduced to less than 75 min without requiring any extra process such as DNA extraction step and sample plate preparation after the punching step. Thereby, newborn SMA screening with the NLM has gained an environmentally friendly feature with not requiring additional tedious steps.

The use of a new ECG patch for exercise and prolonged monitoring: usability, evaluation of signal quality and utility to detect arrhythmias

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ITEA. Background Accurate detection of myocardial ischemia and arrhythmia’s during free-living exercise could play a pivotal role in optimizing screening and monitoring of individuals with underlying cardiovascular disease. Although remote electrocardiogram (ECG) solutions are emerging rapidly, these applications are generally not designed nor validated for continuous use during vigorous exercise. Purpose In this proof-of-concept study, we evaluated the usability, signal quality and arrhythmia detection of a new self-adhesive dry electrode ECG patch, the Nighthawk Vital Signs patch, during exercise and prolonged continuous ECG monitoring in individuals with chronic coronary syndrome (CCS). Methods Six consecutive CCS patients scheduled for an exercise stress test as part of routine cardiac follow-up were recruited. The traditional 12-lead exercise ECG was combined with monitoring with the 1-lead patch. Following the exercise test, the subjects continuously wore the sensor for five days. Intraclass correlation coefficients (ICC) and Wilcoxon signed-rank tests were used to assess the utility to detect arrhythmias with the patch. Signal quality for ECG recording was evaluated by using a signal quality indicator (SQI) based on the average QRS complex. Connection time and signal-to-noise ratio (SNR) were additionally calculated for prolonged ECG monitoring. Comfort and usability of the patch were evaluated by an online questionnaire. Results Six male patients with CCS (mean age 69.8 ± 6.2 years) completed the protocol. The mean time the patch was worn, was 118.3 hours (SD 5.6). The level of agreement between the patch and the 12-lead ECG was excellent for amount of premature atrial contractions (PAC’s) and premature ventricular contractions (PVC’s) during exercise stage, recovery stage and total test duration (ICC = 0.998, 0.998, 1.000, 1.000, 0.998, 1.000). There were no significant differences in the total amount of PAC’s and PVC’s detected with both methods during the exercise test (p = 0.785 and 0.180, respectively). One episode of atrial fibrillation was detected identically on both recorded ECG’s. Signal quality based on average QRS SQI during exercise did decrease slightly during (sub)maximal effort. Total connection time during recording was above 88% in all subjects and the SNR was above the target limit of 18dB. There were no reports on skin irritation, erythema or pain. Conclusion The Nighthawk Vital Signs ECG patch based on self-adhesive dry electrodes technology can be used for accurate arrhythmia detection during vigorous exercise. The sensor is also usable for prolonged ECG monitoring in free-living conditions and can therefore be of potential use in cardiac rehabilitation and telemonitoring for prevention of exercise-related cardiovascular events. However, more research is needed in order to analyze the signal quality over time together with a larger-scale validation study focusing on both arrhythmia and ischemia detection.

Odor exploration behavior of the domestic pig (Sus scrofa) as indicator of enriching properties of odors.

Although the sense of smell in pigs is widely recognized as being highly developed, surprisingly little is known about their sensory ability. This study aimed to (a) identify which non-social odors pigs were able to detect and distinguish between, (b) investigate the types of behavior expressed when exploring odors and, (c) compare pigs' responses to the different odors to evaluate their interest in the odors. Growing pigs (N = 192) of crossbred commercial breeds were enrolled in the experiment (32-110 days of age, weighing 64.9 ± 10.1kg). Littermate pairs of opposite sex were tested in test pens with two odor insertion points in the pen wall, 55 cm apart. All pigs were habituated to the test pens and experimenters. Twelve odors were tested (eight essential oils and four synthetic perfumes) in groups of three odors, with each pig pair tested once with one set of three odors (all possible orders of the three odors were tested on 24 pairs in total), always against a non-odor control (demineralized water). In a test, each of the three odors were presented during three trials in a row (a total of 9 trials per test; trial duration: 1 min; inter-trial breaks: 2 min; total test duration: 25 min). Response variables included: duration of sniffing, feeding-related behavior (licking, biting and rooting), agonistic behavior (biting, displacement and pushing) and no approach of the odor or control, recorded throughout each 1-min odor presentation. All pigs sniffed an odor less when repeatedly presented (LMM: all odors P < 0.05), and significantly longer at the subsequent presentation of a new odor [LMM (3rd vs. 1st presentations): P < 0.001]. Specific odor and odor type (essential oil vs. synthetic perfume) had no significant effect on sniffing duration. Overall, feeding-related behavior and agonistic behavior were expressed significantly more when pigs explored the odor compared with the control insertion point (Paired t-tests: P < 0.001), and specific odor only affected the expression of feeding-related behavior. Collectively, pigs express sniffing, agonistic, and feeding-related behavior when exploring odors, which suggests that pigs perceive odors of non-social origin as a resource. Odors may thus constitute relevant enrichment material for pigs.

A highly efficient and accurate method of detecting and subtyping Influenza A pdm H1N1 and H3N2 viruses with newly emerging mutations in the matrix gene in Eastern Taiwan.

The rapid identification of Influenza A virus and its variants, which cause severe respiratory diseases, is imperative to providing timely treatment and improving patient outcomes. Conventionally, two separate assays (total test duration of up to 6 h) are required to initially differentiate Influenza A and B viruses and subsequently distinguish the pdm H1N1 and H3N2 serotypes of Influenza A virus. In this study, we developed a multiplex real-time RT-PCR method for simultaneously detecting Influenza A and B viruses and subtyping Influenza A virus, with a substantially reduced test duration. Clinical specimens from hospitalized patients and outpatients with influenza-like symptoms in Eastern Taiwan were collected between 2011 and 2015, transported to Hualien Tzu Chi Hospital, and analyzed. Conventional RT-PCR was used to subtype the isolated Influenza A viruses. Thereafter, for rapid identification, the multiplex real-time RT-PCR method was developed and applied to identify the conserved regions that aligned with the available primers and probes. Accordingly, a multiplex RT-PCR assay with three groups of primers and probes (MAF and MAR primers and MA probe; InfAF and InfAR primers and InfA probe; and MBF and MBR primers and MB probe) was established to distinguish these viruses in the same reaction. Thus, with this multiplex RT-PCR assay, Influenza B, Influenza A pdm H1N1, and Influenza A H3N2 viruses were accurately detected and differentiated within only 2.5 h. This multiplex RT-PCR assay showed similar analytical sensitivity to the conventional singleplex assay. Further, the phylogenetic analyses of our samples revealed that the characteristics of these viruses were different from those reported previously using samples collected during 2012-2013. In conclusion, we developed a multiplex real-time RT-PCR method for highly efficient and accurate detection and differentiation of Influenza A and B viruses and subtyping Influenza A virus with a substantially reduced test duration for diagnosis.

Seepage characteristics in unsaturated dispersive soil considering soil salinity and density impacts: Experimental and numerical combined study

Seepage in dispersive soils has contributed to inducing severe damage to hydraulic structures worldwide, whereas its targeted quantitative and refined characterizations have long been overlooked. This study jointly adopted the laboratory constant-head seepage test and Hydrus-1D simulation to explore the dynamic seepage behavior in compacted unsaturated salt-affected dispersive soil columns (lean clay with sand). The impacts of two crucial factors including initial soil soluble salt content (η0, 0.3%, 1.0%, 2,0%) and dry density (ρd, 1.44, 1.53, 1.62 g/cm3) were considered. The matric suction of each experimental case was measured to characterize initial unsaturation, and the post-seepage particle and pore distributions of a representative case were measured to clarify the seepage consequence. Furthermore, the spatiotemporal evolutions of water, soluble salt, and hydraulic conductivity during seepage were captured. Laboratory results suggested that the advance of the wetting front conformed to a power function. Increasing η0 and ρd reduced and prolonged the total test duration by 19.2%-38.2% and 4.4%-38.6%, respectively. Since dispersive soil features a water-sensitive skeleton, fine particles could be dragged downward by water flow, thus simplifying the pore microstructure near the soil column top. Under such a low head of 2 cm here, this finding implied that the threshold hydraulic gradient corresponding to the formation of internal erosion in dispersive soil can be quite low. Based on simulation results, rapid salt accumulation formed where the wetting front arrived in contrast to the following slower leaching process. Higher η0 contributed to stronger permeability. The magnitude order of hydraulic conductivity ranged between 10−16 and 10−7 m/s from initially unsaturated state to saturated state, and that of saturated soil was mainly 10−8 m/s, reflecting the poor permeability of dispersive soil. These novel findings are expected to deepen the soil–water interaction understanding and further guide the rational treatment and application of this problematic special soil in engineering practice.

Wear Performance of Circular Shim against Cam in Engine Bench Test.

Unlike the conventional engine, the valve train of a certain type of engine uses a circular shim instead of a tappet to wear against the cam. To verify the reliability of the shim, an engine bench test was used to test its wear performance. The total duration of the bench test was 1000 h, which was divided into three stages. In each stage, the test equipment was stopped, and the shims were disassembled to observe the surface morphology during the worn process. Precious long-term data were obtained. With the extension of the bench test time, weight loss increased. The maximum weight loss occurs 1000 h after worn, which is about twice that of 350 h. During the wear process, a plastic flow of material was found on the subsurface, and fatigue wear marks occurred on the surface. With an increase in test time, the wear marks increased, leading to material spalling and the formation of pits. The wear mechanism was the mixed wear of fatigue wear and adhesive wear.

Heart rhythm assessment in elite endurance athletes: A better method?

IntroductionArrhythmias also occur among elite endurance athletes. Conventional diagnostic tools for assessment of arrhythmias suffer from limited availability and usability challenges, particularly under the demanding training conditions of an elite athlete. Among endurance athletes, there is a need for out-of-hospital monitoring to enhance detection of arrhythmias under conditions that are relevant and potentially provocative of underlying pathology. The Norwegian patch ECG247 Smart Heart Sensor has been developed to simplify the assessment of heart rhythm disorders. The current study aimed to evaluate the ECG247 Smart Heart Sensor function and usability in an elite athlete environment.MethodsA total of 13 professional cyclists from the UNO-X Pro Cycling Team were examined with the ECG247 Smart Heart Sensor during training camp in Spain, December 2021. All ECG data were analyzed by cardiologists at Sorlandet Hospital Arendal, Norway. The athletes also completed a brief questionnaire registering their training (from on-bike monitoring units) and provided self-assessment of usability parameters after the test.ResultsIn 8 of 13 athletes (69% male, age 23 ± 4 years), two test periods were performed with different ECG patches, resulting in a total of 21 tests with continuous ECG monitoring. Average total ECG test duration per athlete was 144 ± 47 h (89 ± 24 h/patch). Athletes performed an average of 15 ± 5 training h during each test. The ECG quality from all tests was considered satisfactory for rhythm analysis—also during exercise. The reported usability of the ECG247 Smart Heart Sensor was high, and no athletes reported trouble sleeping or training with the sensor. The automatic arrhythmia algorithm reported episodes of possible arrhythmias in 5 (24%) tests; 2 atrial flutter, 2 supraventricular tachycardia and 1 bradycardia (heart rate <30/min). Manual assessment by physicians verified the episode of bradycardia but revealed normal sinus rhythm in all other tests. No false negative events were identified in over 1,800 h of ECG collection.ConclusionThe ECG247 Smart Heart Sensor allowed for high quality ECG monitoring with high usability during intensive exercise in athletes.

Guidance on Applied Pressure Heads for Quantifying Cohesive Soil Erodibility with a Jet Erosion Test (JET)

Highlights Jet erosion test (JET) is a commonly used instrument for quantifying soil erodibility. Uncertainty remains on an appropriate applied pressure head to ensure high-quality JET data. Numerical analysis was used to derive minimum and maximum heads for four soil classifications. Ideal applied pressure heads depend on soil erodibility parameters and user-selected JET characteristics. Abstract. The Jet Erosion Test (JET) is one of the few instruments available for measuring cohesive soil erodibility in situ, but uncertainty remains regarding an appropriate initial applied pressure head for the test. Users typically iterate on an initial applied pressure head setting when testing soil. This iteration is necessary to ensure a reasonable erosion rate and the total amount of scour while imposing applied shear stresses that match the expected application range when using JET-derived erodibility parameters. This research used a numerical analysis of simulated JETs to determine both minimum and maximum applied pressure heads, ensuring a logistically appropriate estimation of soil erodibility parameters. First, the minimum head was set to generate at least 25 mm of scour, established based on data from previous in situ JETs. Second, the maximum applied pressure head was set to ensure that no excessively large initial applied shear stress impacted the estimation of erodibility parameters from a linear regression on erosion rates. Analyses were conducted for four selected soil erodibility classes: highly erodible, more erodible, erodible, and moderately resistant soils. Curves showing the ideal applied pressure ranges were generated for initial time intervals of scour depth measurements of 60, 90, 120, 180, 240, and 360 s and dimensionless initial nozzle heights of 1.00, 1.25, and 1.50. The appropriate range in the applied pressure head depended not only on the soil erodibility classes but also on the initial time interval for scour depth measurements, total test duration, and dimensionless initial nozzle height above the soil surface. Users should ensure that a minimum applied pressure head is exceeded for resistant soils. Maximum applied pressure heads should be considered for erodible, more erodible, and highly erodible soils, dependent on the initial time interval for scour depth measurements and dimensionless initial nozzle heights. Wider ranges of acceptable applied pressure heads were observed with smaller initial time intervals. The procedure presented in this research can be readily adapted by JET users to reflect specific testing conditions (e.g., different data collection intervals and test durations) for ensuring the a priori use of effective pressure head settings. Keywords: Cohesive soils, Erodibility, Jet erosion test, Pressure head, Soil erodibility.

Time optimization of the step loading technique in hydrogen embrittlement small punch tests

The small punch tests consists of punching a plane small specimen until it breaks. This technique is very interesting in situations where there is a shortage of material. In recent works, it has been used with steel employed in aggressive environments, to estimate the threshold stress under which subcritical cracking will never occur. It has been presented in previous papers in combination with standard ASTM 1624, applying gradually increasing constant loads until the sample fails, to reduce the duration of the test and the results dispersión.In the present paper, a further optimization is performed on the steps durations for SPT, simplifying the test and therefore helping to reduce the lab workload while at the same time saving costs and resources and increasing productivity. The present work is carried out on an X80 medium-strength rolled steel in hydrogen embrittlement environments under three different levels of cathodic polarization in an acid electrolyte; the chosen steel belongs to the lowest hardness range (33 ≤ HRC < 45) according to the ASTM 1624 standard. Different steps duration from 10 to 60 mintures had been analyzied, cocluding that 20–40 min for 1st to 10th and 11th to 20th steps respectivley are proposed as the minimum ones to reach accurate results. The proposed optimization allows to reduce the total test duration, being for sure of great interest for the metal industry as well as for the scientific comunity.

Evaluation of the instrumented Timed Up and Go test as a\xa0tool to measure exercise intervention effects in nursing home residents: results from a\xa0PROCARE substudy

Background and objectivesTo achieve independence in activities of daily living, a certain level of functional ability is necessary. The instrumented Timed Up and Go (iTUG) test provides guidance for appropriate interventions, for example, when considering the subphases within the TUG. Therefore, we evaluated the iTUG as a tool to measure the effects of a multicomponent exercise intervention on the iTUG subphases in nursing home residents.MethodsFifty long-term nursing home residents (34 women, 82.7 ± 6.46 [65–91] years; 16 men, 78.6 ± 7.0 [62–90] years) performed the iTUG test before and after a 16-week intervention period (2 × 45–60 min/week). According to the attendance rates, participants were divided into three groups.ResultsThe total iTUG duration decreased from baseline to posttest, F(2,46) = 3.50, p = 0.038, η2p = 0.132. We observed significant correlations between the attendance rates and the total iTUG duration (r(50) = 0.328, p = 0.010). However, we did not observe significant group × time interaction effects in the subphases. The Barthel Index moderated the effect between attendance rate and the total duration of the iTUG test, ΔR2 = 8.34%, F(1,44) = 4.69, p = 0.036, 95% CI [0.001, 0.027].ConclusionsWe confirmed the effectiveness of the iTUG as a tool to measure exercise intervention effects in nursing home residents, especially when participants exhibit high attendance rates. That said, mobility needs to be considered in a more differentiated way, taking into account parameters in the subphases to detect changes more sensitively and to derive recommendations in a more individualized way.

Patient and technician perspectives following the introduction of frontloaded visual field testing in glaucoma assessment

ABSTRACT Clinical relevance Frontloaded visual field testing (twice per eye per session) is well-tolerated by patients and technicians, representing a viable strategy that can be implemented in routine clinical practice to capture enough clinical perimetry data for effective disease diagnosis, surveillance and management. Background To determine the experiences of patients and technicians following the implementation of frontloaded visual field testing (multiple tests per eye within the same session) in a glaucoma service. Methods This was a retrospective, cross-sectional study. A written questionnaire was administered to patients (three questions) attending the glaucoma service at the Centre for Eye Health for glaucoma assessment and to their administering perimetry technicians (two questions). The questionnaire was administered after static automated perimetry (24-2 SITA-Faster on the Humphrey Field Analyzer) was performed twice for each eye (frontloaded) within the same session. Respondents were asked to provide a 1-5 Likert scale response to questions that targeted operational issues for frontloaded visual field testing. Responses were correlated against to demographic (age, gender, ethnicity) and clinical (diagnosis, refractive error, visual field indices, test duration) parameters. Results Approximately 90% of patient respondents agreed that frontloaded visual field testing was clearly explained to them, that they were comfortable during the test, and would prefer completing the tests at a single visit rather than returning to repeat the test. Most technician respondents were also able to keep their patients comfortable. 13% of technician respondents felt they ran late during the session, but on average, the total test duration for four visual field tests was 13 minutes, including breaks. There was no correlation found between demographic and clinical factors, and the responses. Conclusions Frontloaded visual field testing was well-tolerated by patients and technicians. Strategies that may be helpful for other clinics to adopt this new paradigm are described.

Experimental Determination of the Heat Transfer Coefficient of Real Cooled Geometry Using Linear Regression Method

The scope of this work was to develop a technique based on the regression method and apply it on a real cooled geometry for measuring its internal heat transfer distribution. The proposed methodology is based upon an already available literature approach. For implementation of the methodology, the geometry is initially heated to a known steady temperature, followed by thermal transient, induced by injection of ambient air to its internal cooling system. During the thermal transient, external surface temperature of the geometry is recorded with the help of infrared camera. Then, a numerical procedure based upon a series of transient finite element analyses of the geometry is applied by using the obtained experimental data. The total test duration is divided into time steps, during which the heat flux on the internal surface is iteratively updated to target the measured external surface temperature. The final procured heat flux and internal surface temperature data of each time step is used to find the convective heat transfer coefficient via linear regression. This methodology is successfully implemented on three geometries: a circular duct, a blade with U-bend internal channel, and a cooled high pressure vane of real engine, with the help of a test rig developed at the University of Florence, Italy. The results are compared with the ones retrieved with similar approach available in the open literature, and the pros and cons of both methodologies are discussed in detail for each geometry.

Sa1252 PROSPECTIVE EVALUATION OF SYMPTOM CORRELATION FOR GASTROESOPHAGEAL REFLUX DISEASE BY AMBULATORY WIRELESS PH MONITORING AFTER PER-ORAL ENDOSCOPIC MYOTOMY

Ambulatory pH monitoring following POEM is reportedly abnormal in up to 60% of patients. There are limited data regarding correlation of patient reported symptoms with reflux episodes during these studies after POEM. To evaluate the relationship of patient reported typical and atypical GERD symptoms to objective reflux episodes by ambulatory pH monitoring after POEM. From a prospective database, consecutive patients who underwent POEM for esophageal motility disorders at our hospital were identified. High resolution impedance manometry (HRM) and Eckardt scores (ES) were recorded at baseline. At 6 months after POEM, HRM, ES and 48-hour ambulatory wireless pH testing (Bravo, Medtronic, Minneapolis, MN) off antisecretory therapy were obtained. Symptoms experienced during pH testing were recorded. A positive pH study was defined as pH <4 in >5.3% of time on day 1 alone, day 2 alone or total test duration. A symptom index (SI) score (percentage of a GERD-related symptom that correlates with a pH event <4) and symptom sensitivity index (SSI) (percentage of test duration events with pH <4 that are associated with symptoms) were calculated. Symptom-reflux correlation was defined as SI ≥50% or SSI ≥ 10%. 208 consecutive patients underwent POEM between 2015 and 10/2019. The study population included 93 patients (52 ± 17 yrs.; 53M) who underwent follow-up testing 6 months after POEM. The most common indication for POEM was type 1 (18%), type 2 achalasia (58%) and EGJOO (13%). At 6 month follow-up, there were significant decreases in mean ES (1.3 ± 1.9 vs. 7.7 ± 1.9) and mean IRP (8.7 ± 6.4 mmHg vs. 29.6 ± 15.3 mmHg, both p<0.001). A positive pH test was present in 70/93 (75%). The frequency of reported symptoms and their correlation with events during pH testing are recorded in Table 1. At least one symptom was reported by 58/93 (62%), the most frequent of which were cough (29%), heartburn (27%), and chest pain (27%). All reported symptoms had an SI <50% and SSI<10%. For all 3096 reported symptoms, SSI was 9.9%. There was no difference in the frequency of any reported symptom in patients with and without a positive pH study (Table 2). In this series, 75% of post-POEM patients evaluated had abnormal wireless pH testing. Both typical and atypical symptoms of GERD after POEM showed poor correlation with abnormal acid exposure and occurred with equal frequency among those with and without abnormal pH testing. Objective testing rather than patient reported symptoms are required to diagnose, treat and prevent potential complications from post–POEM GERDView Large Image Figure ViewerDownload Hi-res image Download (PPT)

Influence of daily beer or ethanol consumption on physical fitness in response to a high-intensity interval training program. The BEER-HIIT study

BackgroundHigh-intensity interval training (HIIT) is an effective approach to improve physical fitness, but consuming beer, which is a regular practice in many physically active individuals, may interfere with these effects. The purposes of this study were to investigate the effects of a 10-week (2 days/week) HIIT program on cardiorespiratory fitness, muscle strength and power parameters, and also to assess the possible influence on them of a moderate consumption of beer (at least from Monday to Friday) or its alcohol equivalent.Methods: Young (24 ± 6 years old) healthy adults (n = 73, 35 females) were allocated to five groups. Four groups participated in the HIIT intervention program while the fifth group was a control Non-Training group (n = 15). Participants in the training groups chose whether they preferred receiving alcohol or alcohol-free beverages. Those choosing alcohol were randomized to either beer or ethanol intake: (i) T-Beer group (alcohol beer, 5.4%; n = 13) or (ii) T-Ethanol (sparkling water with vodka, 5.4%; n = 14). Those choosing alcohol-free intake were randomized to (iii) T-Water group (sparkling water, 0.0%; n = 16), or (iv) T-0.0Beer group (alcohol-free beer, 0.0%; n = 15). Men ingested 330 ml of the beverage at lunch and 330 ml at dinner; women ingested 330 ml at dinner. Before and after the intervention, maximal oxygen uptake in absolute and relative terms (VO2max.), maximal heart rate, total test duration, hand grip strength and four types of vertical jumps were measured.ResultsHIIT induced significant improvements in absolute and relative values of VO2max, and total test duration (all p < 0.05) in all the training groups; also, clinical improvements were found in hand grip strength. These positive effects were not influenced by the regular intake of beer or alcohol. No changes in the vertical jumps occurred in any of the groups.ConclusionsA moderate beer or alcohol intake does not mitigate the positive effect of a 10-week HIIT on physical fitness in young healthy adults.Trial registrationClinicalTrials.gov ID: NCT03660579. Registered 20 September 2018. Retrospectively registered.