Interaction of wrestling shoe and competition surface: effects on coefficient of friction with implications for injury

The purpose of this study was to determine whether there is a significant difference in the co-efficient of friction (Fc) between old versus new wrestling shoes and mats and to investigate the effect of perspiration. Fc was measured by dragging a weighted shoe over a wrestling mat surface and measuring the vertical and horizontal forces produced. Three different shoe conditions were assessed over two mat types for both wet and dry conditions for a total of 12 conditions. To simulate the wet condition, saline solution was smeared over the surface of the mat. There was a significant effect of shoe, mat, and wet/dry conditions. In addition, significant interactions of shoe by mat, shoe by dry/wet, and mat by dry/wet were observed. Overall, Fc was 36% higher for the new wrestling mat compared to the old wrestling mat. Application of the saline solution reduced Fc by 14% compared to the dry condition. Comparison of the mean Fc for all three shoe types revealed the Fc for the older design shoe was 23% to 28% lower than the brand new shoe and the worn newer design, respectively. A high Fc, such as in the new mat/new shoe combination, has the potential to increase the risk of knee and ankle injuries by fixing the foot more securely to the ground.     

Perceptual judgments for stair climbing as a function of pitch angle

Two experiments explored perception and action for stair climbing, with manipulations to the stair dimensions. In Experiment 1, a custom-built apparatus manipulated the stair dimensions, while three groups of participants made perceptual judgments of climbability. The groups differed significantly for absolute leg length (p < .0001), but there was no significant difference between the groups when stair dimensions were calculated relative to leg length. The selected tread depths and riser heights reflected constant proportions of participants' leg length. Using the pitch angles formed as a composite metric, the results revealed that all groups selected 60 degrees as the limit for climbability. Experiment 2 scaled pitch angle systematically from 20 degrees to 80 degrees, and participants judged 65 degrees and beyond to be unclimbable. These results provided evidence that pitch angle might be used in perceptual judgments for stair climbability.     

Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni.     

Effects of an Educational Experience Incorporating an Inventory of Factors Potentially Influencing Student Acceptance of Biological Evolution

This investigation provides an extensive review of scientific, religious, and otherwise non-scientific factors that may influence student acceptance of biological evolution. We also measure the extent to which students' levels of acceptance changed following an educational experience designed to address an inclusive inventory of factors identified as potentially affecting student acceptance of evolution (n = 81, pre-test/post-test) n = 37, one-year longitudinal). Acceptance of evolution was measured using the Measure of Acceptance of the Theory of Evolution (MATE) instrument among participants enrolled in a secondary-level academic programme during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than initial levels both immediately following and over one year after the educational experience. Results reported herein carry implications for future quantitative and qualitative research as well as for cross-disciplinary instruction plans related to evolutionary science and non-scientific factors which may influence student understanding of evolution.     

Assessing and tracking students’ problem solving performances in anchored learning environments

The purpose of this randomized experiment was to compare the performance of high-, average-, and low-achieving middle school students who were assessed with parallel versions of a computer-based test (CBT) or a paper-pencil test (PPT). Tests delivered in interactive, immersive environments like the CBT may have the advantage of providing teachers with diagnostic tools that can lead to instruction tailored to the needs of students at different achievement levels. To test the feasibility of CBT, students were randomly assigned to the CBT or PPT test conditions to measure what they had learned from an instructional method called enhanced anchored math instruction. Both assessment methods showed that students benefited from instruction and differentiated students by achievement status. The navigation maps generated from the CBT revealed that the low-achieving students were able to navigate the test, spent about the same amount of time solving the subproblems as the more advanced students, and made use of the learning scaffolds.

Values-Alignment Messaging Boosts Adolescents’ Motivation to Control Social Media Use

Two preregistered experiments with 2,733 U.S. high school students (age range = 13–19 years) compared the impact of different messages on adolescents’ motivation to control social media use (SMU). A traditional message emphasized the benefits of avoiding SMU, whereas a values-alignment message framed controlling SMU as being consistent with autonomy and social justice. Compared to no message or a traditional message, in both studies, a values-alignment message led to greater motivation to control SMU immediately afterward, and in Study 2, awareness of “addictive” social media designs 3 months later. As hypothesized, values-alignment messaging was more motivating for girls than boys. Results offer preliminary support for leveraging adolescents’ drives for autonomy and social justice to motivate self-regulation of SMU.     

The Representation of Altruistic and Egoistic Motivations in Children’s TV Programming

A content analysis of children’s television examined the frequency with which behaviors were (a) driven by altruistic versus egoistic motivations, (b) performed by affable/surly characters, (c) rewarded/punished, and (d) present in content popular among different age groups (2–5, 6–11, and 12–17 years old). We found that portrayal patterns stressed the importance of egoistic motivations (particularly competence, autonomy, and relatedness) for older children. The findings are interpreted in line with logic underlying the model of intuitive morality and exemplars (MIME; Tamborini, 2013), suggesting that media representations can influence the motivations of their viewers.     

Unequal academic achievement in high school: the mediating roles of concerted cultivation and close friends

Building from the classic Wisconsin model of status attainment, this study examines whether a specific style of parenting, concerted cultivation, and a close friend’s school-related attitudes and behaviors mediate the relationship between a family’s socioeconomic status and their child’s academic achievement in the United States. Using a recursive path model on nationally representative panel data of high school students (N = 10,350), the results confirm a direct association between socioeconomic status and concerted cultivation. In addition, concerted cultivation and close friends are shown to mediate the relationship between a family’s socioeconomic status and their child’s academic achievement.