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It is known that the chronotype potentially mediates the performance and tolerance to work in shifts and that shift rotation is associated with negative effects on psychomotor performance. This study aimed to evaluate the effect of chronotype on psychomotor performance throughout a complete shift rotation schedule. Thirty males working in clockwise rotating shifts from a mining company were evaluated under a real-life condition over the following shift schedule 2 days of day work, 2 days of evening work and 2 days of night work. The chronotype was determined using the Munich Chronotype Questionnaire adapted for shift workers and the obtained scores were categorized by tertiles (early-type, intermediate-type and late-type). Work performance was evaluated by Psychomotor Vigilance Test (PVT) daily just before shift starts and after shift ends. Sleep duration was evaluated by actigraphy over the whole shift. No isolated effect of the shift or interaction between shift and chronotype was found in the performance variables evaluated. A significant isolated effect of the chronotype showed that the early-type individuals had higher values of pre- and post-work Mean of Reaction Time (MRT) (308.77 ± 10.03 ms and 306.37 ± 8.53 ms, respectively) than the intermediate-type (257.61 ± 6.63 ms and 252.91 ± 5.97 ms, respectively, p  less then  0.001) and the late-type (273.35 ± 6.96 ms and 262.88 ± 6.05 ms, respectively, p  less then  0.001). In addition, late individuals presented a greater number of lapses of attention (5.00 ± 0.92; p  less then  0.05) than early (1.94 ± 0.50, p  less then  0.05) and intermediate (1.33 ± 0.30, p  less then  0.001) ones. We concluded that, compared with intermediates, late-type workers had a greater number of lapses of attention on the shift schedule as a whole, while early-type workers showed the highest pre- and post-work MRT. [https://www.selleckchem.com/products/abr-238901.html learn more] These findings show that the psychomotor performance of rotating shift workers seems to be influenced by the chronotype, but not by the shift rotation.Serious wear phenomena occur in mining machinery under complex working conditions, and the wear of machine parts is primarily caused by the synergistic effect of adhesive wear, abrasive wear, corrosive wear, etc. However, the existing friction and wear testing equipment cannot be used to carry out wear tests under complex working conditions. To simultaneously meet the test requirements of adhesive wear, abrasive wear, and corrosive wear, a novel sliding friction and wear tester that can simulate complex working conditions was developed in the present research. The tester is composed of a loading mechanism, a speed-regulating mechanism, a corrosion chamber, and a control and display system. Wear tests of the middle plate of a scraper conveyor, a key equipment of coal mining, were carried out to verify the consistency and effectiveness of the tester. The test results were consistent, and those under the same test conditions were similar with a maximum standard deviation of 2.4 mg. The wear condition of the middle plate specimens was close to the actual wear condition of the middle plate. Moreover, the surfaces of the middle plate specimens after grinding exhibited obvious adhesive, abrasive, and corrosive wear characteristics, and the wear degrees of the specimens under the same test conditions were similar. The quality loss of the middle plate specimens was found to increase with the increase of coal gangue percentage, and the main wear mechanism was the synergistic action of abrasive, adhesive, and corrosive wear.We present a study of the ground state and stability of the fractional plateau phase (FPP) with M/Msat = 1/8 in the metallic Shastry-Sutherland system TmB4. Magnetization (M) measurements show that the FPP states are thermodynamically stable when the sample is cooled in constant magnetic field from the paramagnetic phase to the ordered one at 2 K. On the other hand, after zero-field cooling and subsequent magnetization these states appear to be of dynamic origin. In this case the FPP states are closely associated with the half plateau phase (HPP, M/Msat = ½), mediate the HPP to the low-field antiferromagnetic (AF) phase and depend on the thermodynamic history. Thus, in the same place of the phase diagram both, the stable and the metastable (dynamic) fractional plateau (FP) states, can be observed, depending on the way they are reached. In case of metastable FP states thermodynamic paths are identified that lead to very flat fractional plateaus in the FPP. Moreover, with a further decrease of magnetic field also the low-field AF phase becomes influenced and exhibits a plateau of the order of 1/1000 Msat.The inter-session Intraclass Correlation Coefficient (ICC) is a commonly investigated and clinically important metric of reliability for pressure pain threshold (PPT) measurement. However, current investigations do not account for inter-repetition variability when calculating inter-session ICC, even though a PPT measurement taken at different sessions must also imply different repetitions. The primary aim was to evaluate and report a novel metric of reliability in PPT measurement the inter-session-repetition ICC. One rater recorded ten repetitions of PPT measurement over the lumbar region bilaterally at two sessions in twenty healthy adults using a pressure algometer. Variance components were computed using linear mixed-models and used to construct ICCs; most notably inter-session ICC and inter-session-repetition ICC. At 70.1% of the total variance, the source of greatest variability was between subjects ([Formula see text] = 222.28 N2), whereas the source of least variability (1.5% total variance) was between sessions ([Formula see text] = 4.83 N2). Derived inter-session and inter-session-repetition ICCs were 0.88 (95%CI 0.77 to 0.94) and 0.73 (95%CI 0.53 to 0.84) respectively. Inter-session-repetition ICC provides a more conservative estimate of reliability than inter-session ICC, with the magnitude of difference being clinically meaningful. Quantifying individual sources of variability enables ICC construction to be reflective of individual testing protocols.