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Abstract Introduction The purpose of this study was firstly to compare the impact of radiographs, cone-beam computed tomographic (CBCT) imaging, and 3D Endo software (Dentsply Sirona, Ballaigues, Switzerland) on the assessment of root canal anatomy and radiographic quality of endodontic treatment and secondly to assess stress levels in the same cohort of residents performing endodontic treatment. Methods Sixty patients requiring primary molar endodontic treatment were allocated randomly into 3 groups: group 1 (n = 20), conventional radiographs (periapical radiography [PR]) only; group 2 (n = 20), PR and CBCT imaging; and group 3 (n = 20), PR, CBCT imaging, and 3D Endo software. All treatment was performed using a standardized protocol. Residents completed a questionnaire to assess their stress levels and usefulness of the imaging modality used. The radiographic quality of completed cases was assessed by 2 experienced endodontists who were not involved in the supervision of the cases being assessed. Results Groups 2 (CBCT imaging) and 3 (PR, CBCT imaging, and 3D Endo) proved significantly better than group 1 (PR) (P <.001) for assessing the number of root canals and anatomy and estimating the working lengths. Group 3 provided a significantly more accurate determination of the working level (P =.002). There were significantly more cases with obturation short of the apex (<2 mm) and voids in group 1 compared with group 3 (P <.05) and a significantly higher number of cases with voids in group 1 compared with group 3 (P <.01). Clinicians found treatment to be moderately or very stressful in 75%, 5%, and 0% in groups 1, 2, and 3, respectively. Conclusions 3D Endo software followed by CBCT imaging were found to be more desirable for the evaluation of root canal anatomy and working lengths and reducing the residents' stress levels. [ABSTRACT FROM AUTHOR]

To quantify the fatigue behaviour of materials, a Wöhler diagram is required. The state of the art shows that, over the years, numerous approaches suitable for determining Wöhler curves have been devised and validated through large fatigue data sets. The variation in experimental fatigue data elicits the use of statistics for analysis and design purposes. By focusing on the medium-cycle fatigue regime (i.e., failures in the range 103÷107 cycles to failure), this paper reviews relevant statistical approaches, particularly the methods suggested by the American Society for Testing Materials (ASTM) as well as the International Institute of Welding (IIW) and the so-called Linear Regression Method (LRM). Their responses were assessed on virtual data sets tailored to satisfy specific statistical requirements as well as experimental fatigue data sets from the literature. While the scatter bands at two times or less of the spread are similar for all approaches, the ASTM approach is seen to be the most conservative. • Statistical approaches to estimate fatigue design curves are reviewed. • The problem of estimating mean fatigue curves is analysed. • Strategies recommended to be used to determine scatter bands are reviewed. • Standard approaches are assessed based on virtual data sets. [ABSTRACT FROM AUTHOR]

In an attempt to characterize the permanent deformation behavior of hot mix asphalt (HMA) under a more realistic loading condition, this study developed a multi-sequenced repeated load (MSRL) test. Comparing to conventional repeated load (RL) test, there are three characteristics for this new test. First, the loading scheme, containing a pre-loading sequence with stress level of 0.7 MPa and other 25 sequences involving stress levels from 0.6 MPa to 1.0 MPa, was self-defined by the test design function of UTM-25. Second, the number of repeated loading in each sequence was fixed, with 500 times in pre-loading and 50 times in every other sequence. Third, two new indicators, including compound average strain rate (CASR) and compound creep stiffness modulus (CCSM), were proposed to evaluate the rutting-resistant property of HMA. Both MSRL test at different loading orders and RL test under stress levels of 0.7 MPa and 1.0 MPa were conducted on three types of mixtures with two binders at temperature of 60 °C, respectively. The findings indicate that the effects of loading order are insignificant on the permanent deformation of HMA in secondary stage. Besides, average strain rate (ASR) has a nonlinear growth as stress level increases. Based on MSRL test results, coefficient of variance for new indicators is satisfactory. Through analysis of variance, it is also found that new indicators, with much reduced levels of confidence, have much better potentials to statistically differentiate mixtures with different SBS modified binders than conventional ones like flow number (FN), FN index and so on. [ABSTRACT FROM AUTHOR]

Accurately monitoring forest insects and diseases disturbances is important for managing forests and implementing effective forest quality improvement measures. However, monitoring disturbances in the lower and middle parts of the forest canopy with traditional remote sensing technologies is difficult. A new sensor called hyperspectral LiDAR (HSL) makes the monitoring of these forest disturbances possible, however, its applicability to canopy scale has not been fully studied due to the current hardware limitation. This paper assessed the potential of airborne hyperspectral LiDAR (AHSL) for monitoring forest insects and diseases stress using 3D radiative transfer modeling and in-situ measurements. A virtual 3D forest scene with explicitly described structures was first reconstructed from terrestrial laser scanning and field measurement data, upon which a number of different insects and diseases disturbance scenarios with different damage locations and stress levels were defined. AHSL point cloud and the corresponding hyperspectral image (HI) were then simulated with large-scale and remote sensing image simulation (LESS) model for each combination of the different damage locations and stress levels. LiDAR point cloud from different layers of the simulated AHSL point cloud were then extracted and rasterized into images with 3-m spatial resolution, which, along with the hyperspectral images, were used to test the insect and disease monitoring ability by using a random forest model. Results show that AHSL has significant higher overall accuracies (OA: 65.95% ∼ 89.45%) than HI (OA: 33.99% ∼ 57.02%) for predicting insects and diseases stress levels. Compared to AHSL, HI is affected by a variety of factors such as soil and shadows, resulting in poorer monitoring capability for different damage locations, with the highest classification accuracy in the case of entire canopy damage (OA: 57.02%). For AHSL, it has good classification accuracy for all damage locations, with the lowest accuracy in the case of lower canopy damage (OA: 65.95%). This study demonstrates that AHSL is a promising and reliable tool to monitor forest disturbances, especially for structural and spectral changes in the lower and middle parts of canopy, which may have great potential for early detecting forest insects and diseases. • Explicitly described 3D damaged virtual forests were constructed from TLS. • The potential of AHSL to detect forest pests and diseases was assessed using 3D RTM. • AHSL shows higher accuracy to detect pests and diseases than hyperspectral image. • AHSL is capable of detecting pest and disease in lower and middle forest canopy. [ABSTRACT FROM AUTHOR]

An optional multiple repeated load (OMRL) test, capable of simulating the axial load spectrum in real pavement, was developed to evaluate the rutting susceptibility of asphalt mixture. This new test was conducted at the temperature of 60 °C under multiple stresses determined by a simplified axle load spectrum considering the pavement management system (PMS). A pre-stage dynamic creep test was employed to determine the loading cycles of the first increment. Two kinds of asphalt mixtures were compared in the OMRL test with varying orders of multiple stresses and they were also tested in dynamic creep test under five different loading levels. As the test results show, loading sequences have a significant impact on the high-temperature performance of asphalt mixtures. The curve of permanent strain rate versus stress level could fit well with a power-law model in the dynamic creep test, and a similar result can be obtained by the OMRL test. However, the OMRL test shows higher efficiency than the traditional dynamic creep test. Besides, the secondary stage of the OMRL test fits a broken-line model since various stress levels are conducted on the specimen. The newly proposed lowest average strain rate (LASR) and multiple flow number (MFN) could evaluate the rutting resistance of asphalt mixtures under a more realistic loading condition. Overall, this OMRL test provides a better understanding of the rutting behavior of asphalt mixtures to improve the mix design and field performance. [ABSTRACT FROM AUTHOR]

• The additional money incentive method is used to mimic emergency situations. • The pedestrians' evacuation performance and the impact of guides' positions on evacuation efficiency under different stress levels are analyzed. • The effect of guidance on pedestrians' decision-making is investigated. In emergencies, guides play a significant role for evacuees who are unfamiliar with the environment. Proper guidance can improve evacuation efficiency, and the position of guidance is particularly important. However, most studies are focused on the simulation model to explore the optimal guidance position and the experiments are less conducted. In addition, the pedestrians' behaviors under emergency conditions are usually different from those in normal conditions. In this work, several controlled experiments were conducted to study the effect of guidance positions and stress levels on evacuation efficiency and pedestrians' behavior. The results show that the pedestrians have a better evacuation performance with guidance under high-stress conditions. Compared with the low-stress level, the pedestrians under the high-stress level evacuate faster and the flow is more continuous. The pedestrians under the high-stress level take longer to make decisions when the exit is unknown but show larger competitiveness when the goal is clear. Besides, guidance can improve evacuation efficiency due to providing exit information to pedestrians. It also reveals that guidance mainly influences the pedestrians who are located nearby and has the greatest effect on helping those far from the exit. These findings can provide empirical data about the effect of guidance on emergency evacuation and further the understanding of pedestrian behaviors in high-stress conditions, which are valuable for crowd management. [ABSTRACT FROM AUTHOR]

Abstract: Peak lithospheric strength should reside in the rocks that, under the applied stress, cannot either creep (due to low temperature) or break (due to high confining pressure). The greatest resistance comes from dry olivine/pyroxene-rich upper mantle/lowermost crust at Moho conditions (400–600 °C and >1 GPa). We have conducted laboratory experiments to investigate the importance of the unbreakable core of the lithosphere in between its brittle and ductile parts and conclude that it can control the large-scale lithospheric deformation pattern under shortening. Regardless of the thickness of the unbreakable core, it acts as a restraining layer that is easily flexed but is unstretchable. This eliminates large scale brittle faulting or homogeneous thickening as available shortening modes and results in irregular wrinkling of the unbreakable layer. We discuss geodynamic implications of our laboratory experiments and advocate studies of large scale buckling of the lithosphere as a relevant shortening mode. [Copyright &y& Elsevier]

• Internists have a 30.7% higher rate of detection of fake news compared to nonscientists. • Internists have accumulated clinical levels of stress since the onset of the COVID-19 pandemic. • The use of critical thinking predicts more than 40% of the variance in reductions in perceived stress. • Skeptical attitudes facilitate the detection of fake news in internal medicine. The prevalence of pseudoscientific beliefs and fake news increased during the coronavirus crisis. Misinformation streams such as these potentially pose risks to people's health. Thus, knowing how these pseudoscientific beliefs and fake news impact the community of internists may be useful for improving primary care services. In this research, analyses of stress levels, effectiveness in detecting fake news, use of critical thinking (CP), and attitudes toward pseudosciences in internists during the COVID-19 crisis were performed. A total of 1129 internists participated. Several multiple regression models were applied using the forward stepwise method to determine the weight of CP and physicians' attitudes toward pseudosciences in predicting reductions in stress levels and facilitating the detection of fake news. The use of critical thinking predicted 46.9% of the reduction in stress levels. Similarly, skeptical attitudes and critical thinking predicted 56.1% of the hits on fake news detection tests. The stress levels of physicians during the coronavirus pandemic were clinically significant. The efficacy of fake news detection increases by 30.7% if the individual was a physician. Study outcomes indicate that the use of critical thinking and skeptical attitudes reduce stress levels and allow better detection of fake news. The importance of how to promote critical and skeptical attitudes in the field of medicine is discussed. [ABSTRACT FROM AUTHOR]

A nine-year-old female with a history of perinatal stroke, seizures, and type-I diabetes was seen for six weeks of Reiki to determine the effects of Reiki on relaxation, and in turn, the prevention of future seizures. The secondary and tertiary aims were to determine the effects of Reiki on sleep patterns and the stress levels of the mother. There was a decrease in stress in both the child and the mother, as measured by a modified Perceived Stress Scale and a Perceived Stress Scale, respectively. There was no change in the child's overall sense of well-being, as measured by a global questionnaire. There was a positive change in sleep patterns on 33.3% of the nights during which the study occurred, as reported on a sleep log kept by the mother. The child and the Reiki Master (a Reiki practitioner who has completed all three levels of Reiki certification training and trains and certifies individuals in the practice of Reiki as well as provides Reiki to individuals) experienced warmth and tingling sensations on the same area of the child during the Reiki sessions. The child relaxed within the first five to seven minutes of each session as reported by the Reiki Master. There were no reports of seizures during this study. Reiki may be a useful adjunct for children with increased stress levels and sleep disturbances secondary to their medical condition. Further research is warranted to evaluate the use of Reiki in children, particularly with a large sample size, and to evaluate the long-term use of Reiki and its effects on adequate sleep. [ABSTRACT FROM AUTHOR]