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BACKGROUND: Sport practice may elevate the risk of cardiovascular events, including sudden cardiac death, in athletes with undiagnosed heart conditions. In Italy, pre-participation screening includes a resting ECG and either the Harvard Step Test (HST) or maximal exercise testing (MET), but the relative efficacy of the latter two tests for detecting arrhythmias and heart conditions remains unclear. METHODS: This study examined 511 paediatric athletes (8–18 years, 76.3% male) without known cardiovascular, renal, or endocrine diseases. All athletes underwent both HST and MET within 30 days. Absolute data and data relative to theoretical peak heart rates, arrhythmias (supraventricular and ventricular) and cardiovascular diagnoses were collected. RESULTS: HST resulted in a lower peak heart rate than MET (181.1 ± 9.8 vs. 187.5 ± 8.1 bpm, p < 0.001), but led to the detection of more supraventricular (18.6% vs. 13.1%, p < 0.001) and ventricular (30.5% vs. 22.7%, p < 0.001) arrhythmias, clustering during recovery (p = 0.014). This pattern was significant in males but not females. Among athletes diagnosed with cardiovascular diseases (22.3%), HST identified more ventricular arrhythmias (26.3% vs. 18.4%, p = 0.05), recovery-phase arrhythmias (20.2% vs. 14.0%, p = 0.035), and polymorphic arrhythmias (6.1% vs. 1.8%, p = 0.025). CONCLUSIONS: HST detects arrhythmias more effectively than MET in young male athletes, especially during recovery. More ventricular arrhythmias were highlighted even in athletes with cardiovascular conditions.

Background: Peak oxygen consumption (VO2) measured by cardiopulmonary exercise testing (CPET) is a significant predictor of mortality and future transplantation in heart failure patients with severely reduced ejection fraction (HFrEF). The present study evaluated the differences in peak VO2 and other prognostic variables between treadmill and cycle CPETs in these patients. Methods: In this cross-over study design, thirty males with severe HFrEF underwent CPET on both a treadmill and a cycle ergometer within 2–5 days apart, and important CPET parameters between two exercise test modalities were compared. Results: Peak VO2 was 23.12% higher on the treadmill than on cycle (20.55 ± 3.3 vs. 16.69 ± 3.01, p < 0.001, respectively). Minute ventilation to carbon dioxide production (VE/VCO2) slope was not different between the two CPET modes (p = 0.32). There was a strong positive correlation between the VE/VCO2 slopes during treadmill and cycle testing (r = 0.79; p < 0.001). VE/VCO2 slope was not related to peak respiratory exchange ratio (RER) in either modality (treadmill, r = 0.13, p = 0.48; cycle, r = 0.25, p = 0.17). The RER level was significantly higher on the cycle ergometer (p < 0.001). Conclusion: Peak VO2 is higher on treadmill than on cycle ergometer in severe HFrEF patients. In addition, VE/VCO2 slope is not a modality dependent parameter and is not related to the patients’ effort during CPET.

The quasi-coherent effects in two-dimensional incompressible turbulence are analyzed starting from the test particle trajectories. They can acquire coherent aspects when the stochastic potential has slow time variation and the motion is not strongly perturbed. The trajectories are, in these conditions, random sequences of large jumps and trapping or eddying events. Trapping determines quasi-coherent trajectory structures, which have a micro-confinement effect that is reflected in the transport coefficients. They determine non-Gaussian statistics and flows associated to an average velocity. Trajectory structures also influence the test modes on turbulent plasmas. Nonlinear damping and generation of zonal flow modes is found in drift turbulence in uniform magnetic field. The coupling of test particle and test mode studies permitted to evaluate the self-consistent evolution of the drift turbulence in an iterated approach. The results show an important nonlinear effect of ion diffusion, which can prevent the transition to the nonlinear regime at small drive of the instability. At larger drive, quasi-coherent trajectory structures appear and they have complex effects on turbulence.

Thermal tests of two types were performed in helium to simulate dry storage conditions for fuel rods with claddings made of Zr-1% Nb (E110) alloy which had been operated in the VVER-1000 reactors up to the average calculated fuel burnup values of 20, 63 and 70 MWd/kg U. The first type of tests was performed under two conditions: steady-state (holding at T = 380°C for 468 days) and thermal cycling (48 thermal cycles at 90°С/380°C with the different duration of cycles from 1 to 10 days and total time of testing was 427 days). The second type of tests had two stages. At the first stage, two modes were achieved: vacuum drying (step-by-step heating and holding at each stage for a day at temperatures of 200, 400, and 440°C) and vacuum drying together with a simulated design basis accident (there was a step-by-step temperature reduction from 440 to 380 and to 360°С after vacuum drying and the time of holding was 14 and 168 hours, respectively). Fuel rods were held at T = 350°С for 404 days at the second stage. The thermal impact caused a decrease in the density of radiation-induced 〈a〉-type dislocations, the ratio of Nb atoms in β-Nb particles, and the size of the particles. Radiation-induced defects in the structure annealed more severely as a result of thermal tests of the first type as compared to the second type. Partial annealing of the radiation-induced defects led to a partial regain of the yield strength of the claddings to the original values to a greater extent in the longitudinal direction rather than in the transverse one. The better recovery of yield strength as a result of thermal tests of the first type rather than of the second type is due to the higher efficiency of temperature impact as a function of time on the microstructure of the E110 alloy that is estimated as the relevant cumulative annealing parameter. Different conditions of each thermal test did not lead to a significant difference in the yield strength recovery. Tensile stresses that occurred in the claddings at high temperatures during thermal tests of both types contributed to the reorientation of zirconium hydrides as the radial orientation factor Fn increased to 0.3 with a minor decrease in their specific length. It did not cause a reduction in the plasticity of the claddings because of the low degree of hydrogenation.

Computer-based testing (CBT), which refers to delivering assessments with computers, has been widely used in large English proficiency tests worldwide. Despite an increasing CBT in China, limited research is available concerning whether CBT can be used for the Test for English Majors-Band 4 (TEM 4). The current study investigated whether testing mode impacted TEM 4 score and factors (i.e., computer familiarity level and attitude towards CBT) that might correlate with performance on CBT of TEM 4. Overall 92 Chinese undergraduate students were randomly assigned to one of the groups, i.e., CBT or paper-based testing (PBT), and took the test. A mixed method was employed, including (1) quantitative and qualitative analysis of test performance in two modes, as well as CBT group participants’ computer familiarity and attitudes towards the mode; and (2) thematic analysis of semi-structured interviews. The results revealed that (1) test scores in CBT and PBT were comparable; (2) two items in the computer familiarity questionnaire, i.e., comfort level of reading articles on the computer and forgetting time when using computers, positively correlated with CBT scores; and (3) participants’ attitude towards CBT did not impact test performance.

Test anxiety is a psychological variable that diversely impacts academic test performance. Test anxiety tools are developed to understand and predict its impact in different test settings. It is important to determine the reliability and validity of these tools to affirm the measures they provide. Additionally, where computers have been used in testing, there is a further need to assess the impact of test anxiety accurately. The purpose of this study was to find out the psychometric properties of the 10-item Westside Test Anxiety Scale (WTAS) that was adapted for use in Kenya. The study also investigated the effect of test mode on test anxiety. The study sample comprised 424 male and female pupils in public primary schools in Nairobi, Kenya. In a between-groups experimental set-up, 208 pupils were assigned randomly to sit a computer-based science test, and 216 pupils were assigned to the paper-based version. The WTAS was thereafter administered to pupils in both groups. An analysis of the test anxiety tool revealed adequate internal consistency and person reliability estimates. The tool also fulfilled the key Rasch model assumptions of local independence. Though all the items fitted the Rasch model, three items had disordered categories. Exploratory factor analysis revealed two additional test anxiety factors. An independent sample t-test showed that test mode had a small and insignificant effect on test anxiety. The study recommended that future studies consider developing localized test anxiety tools rather than adapting from foreign sources.

Recent advancements in virtual reality (VR) technology have enabled its integration into learning diverse aspects of spatial components and relationships in the field of spatial design, as well as designing, communicating, collaborating, and managing complex building projects. With the growing interest in incorporating VR technology in spatial design, examining whether people understand, perceive, and perform spatial tasks in the same way in VR as they do in static modes is essential. Thus, the purpose of this study was to compare spatial ability performance in a conventional static paper–desktop mode and an interactive VR mode. Thirty students completed the Architecture and Interior Design Domain–Specific Spatial Ability Test in both modes. Their visual cognitive style was measured with the Object–Spatial Imagery Questionnaire, and their responses to the usability of the VR mode were analyzed. The results revealed: (a) significant difference in performance between static and VR modes, including better performance in three spatial visualization subconstructs in static mode than in VR; (b) no gender difference in VR mode; (c) a tendency of spatial visualizers to benefit from VR mode; and (d) a tendency of people with high spatial ability to be more susceptible to test mode. Overall, the results contribute to expanding our understanding of spatial ability performance in different test modes and provide insights concerning the integration of VR into the development of spatial ability tools and education.

This study presents a method for developing a tire indoor wear test mode that reflects road driving conditions using a Flat-trac. Using a machine learning model, the slip angle, slip ratio, longitudinal force, and lateral force change according to vehicle speed and acceleration changes are estimated. Reduced data representing the estimated data are calculated using a peak–valley (PV) algorithm. Through the blocking process, representative test modes for driving and braking, right turning and left turning are derived and converted into a test mode for application to the Flat-trac. The evolution of tire tread wear is observed through 120 repeated tests, and the applicability of the test mode developed in this study is discussed.

This study proposes a system that can collect and analyze the brake particle matter generated from a vehicle and brake dynamometer. A dust cover is developed to collect brake particle matter, and the number of particle matter by size is measured using a portable aerosol spectrometer. Brake PM10 generated when the vehicle is driving on highways, country and city roads is collected and analyzed. Based on the vehicle driving data, the test mode for the brake dynamometer is developed using the relationship between brake energy and brake power. The same brake fine dust collection and measurement system as the vehicle is installed on the brake dynamometer, and brake PM10 generated according to the test mode for each road condition is collected and analyzed. As a result, the total number of brake PM10 collected from the vehicle and brake dynamometer shows about maximum of 20% error rate for each road condition. The Pearson correlation coefficient for the test results is 0.9988, and it means that the vehicle and brake dynamometer test results has a strong positive relationship.

When a joined-wing configuration is applied to the design of solar-powered UAVs, the increasing span amplifies aeroelastic effects, while structure complexity poses greater challenges to computational effectiveness during the conceptual design phase. This paper focuses on a large-span joined-wing solar-powered UAV (LJS-UAV) engineering prototype. The structural finite element model of the whole system is constructed by developing the ‘Simplified beam-shell model’ (SBSM) and verified by a structural mode test. A numerical simulation approach is employed to comprehensively analyse and summarise the aeroelastic characteristics of the LJS-UAV from the perspectives of static aeroelasticity, flutter, and gust response. The mode test identified 30 global modes with natural frequencies below 10 Hz, indicating that the LJS-UAV possesses an exceptionally flexible structure and exhibits highly complex aeroelastic characteristics. The simulation results reveal that the structural elasticity induces significant variations in aerodynamic forces, moments, and derivatives during flight, which cannot be neglected. The longitudinal trim strategies can considerably influence the aeroelastic boundary of the LJS-UAV. Utilising the front-wing control surfaces for trim is beneficial in improving structural performance and expanding the flight envelope.