What Aimed Movement Models Fit Distal Pointing With Varying Depth?

OBJECTIVE: With the rapid improvements in drone technology, there is an increasing interest in distal pointing to diffuse drones. This study investigated the effect of depth on distal pointing when the hand does not traverse the entire distance from start to target so that the most suitable mathematical model can be assessed. BACKGROUND: Starting from the Fitts paradigm, researchers have proposed different models to predict movement time when the distance to the target is variable. They do consider distance, but they are based on statistical modeling rather than the underlying control mechanisms. METHODS: Twenty-four participants volunteered for an experiment in a full-factorial Fitts' paradigm task (3 levels of movement amplitude *7 levels of target width *3 levels of distance from participant to screen). Movement time and the number of errors were the dependent variables. RESULTS: Depth has a significant effect when the target width is small, but depth has no effect when the target width is large. The angular version of the two-part model is superior to the one-part Fitts' model at larger distances. Besides, Index of difficulty for distal pointing, IDDP with adjustable k achieves the best fit even though the model is very sensitive to the value of k and the complexity of the model could be resulting in an overfitting. The result implies that the effects of movement amplitude and target width are not comparable and grouping them to form a dependent index of difficulty can be misleading especially when distance is an added variable. CONCLUSION: The angular version of the two-part model is a viable and meaningful description for distal pointing. Even though the IDDP with adjustable k is the best predictor for movement time when depth is an added variable, there is no physical interpretation for it. APPLICATION: A reasonable predictive model for performance assessments and predictions in distal pointing.

Transient pain and discomfort when wearing high-heeled shoes.

In the dynamic world of fashion, high-heeled footwear is revered as a symbol of style, luxury and sophistication. Yet, beneath the facade of elegance of classy footwear lies the harsh reality of discomfort and pain. Thus, this study aims to investigate the influence of wearing high-heeled shoes on the sensation of pain across different body regions over a period of 6 h. It involved fifty female participants, all habitual wearers of high-heeled shoes, aged between 20 and 30 years. Each participant kept a record of their perceptions of pain and discomfort every hour for a total of 6 h using a 0-10 pain scale with 0 indicating no pain and 10 indicating severe pain. The findings reveal a progressive rise in pain throughout wear, with the most intense pain reported in the back, calcaneus, and metatarsals. The analysis shows that after approximately 3.5 h, participants experience significant increases in pain levels. However, the relationship between heel height and pain is not linear. It appears that a heel height of 7.5 cm is the threshold where overall body pain becomes significant. The study suggests that a duration of 3.5 h of wear and a heel height of 7.5 cm serve as critical points to decrease overall body pain. Moreover, beyond this heel height, knee pain diminishes compared to other body areas possibly due to the shift towards a more neutral posture. The study findings, coupled with the recommendations, can assist footwear designers in crafting not only stylish but also comfortable shoes.