3D Knee Kinematics and Kinetics With Visual Disruption in Subjects With ACL Reconstruction

BACKGROUND AND PURPOSE: The anterior cruciate ligament (ACL) is a commonly ruptured ligament among male and female athletes. Women are at a higher risk of ACL injuries compared to men. The leading cause of female ACL injuries has been identified as non-contact mechanisms. Several risk factors for injury among females that have been theorized include: quadriceps/hamstring activation pattern and force production, greater dynamic knee valgus, hormonal influenced laxity and anatomical gender variation. The purpose of this research was to analyze three dimensional (3D) kinetic and kinematic dynamic landing patterns at the knee between ACL reconstructed and healthy females and any interaction effects of visual disruption. METHODS: Seventeen healthy female subjects (25.3± 6 y) and 17 female subjects with an ACL reconstruction (26.5± 6.3 y) were studied. A 3D electromagnetic system measured knee position during a cutting maneuver from an athletic stance position. Anatomic boney landmarks on the occiput, sacrum, femur and tibia were digitized for capture. Subjects began on a force plate and were instructed to catch a ball and cut immediately left or right as indicated by a specific tone, which was randomized (40 trials). Vision was randomly disrupted via shutter glasses for either one second at the beginning of the cutting maneuver or was left intact for the duration of the movement. A two-way repeated measures ANOVA analyzed the differences between healthy and ACL reconstructed subjects and intact vision versus disrupted vision. RESULTS: The results indicate significant differences exist between subjects with ACL reconstruction and healthy subjects for flexion, adduction, and external rotation knee angles and extension, abduction, and internal rotation moments. Significant interactions of group and vision conditions also exist for flexion, adduction, and external rotation knee angles. Vision alone displayed no significant differences for all subjects. CONCLUSION: Years later, subjects with ACL reconstructions continue to display different knee kinematics and kinetics that could increase their risk for re-injury or injury of other leg. Furthermore, visual disturbances have significant effects on ACL reconstructed knee angles and moments when landing compared to healthy subjects. These results support continued movement related rehabilitation with visual disturbances for ACL reconstructed patients

The tripartite-circle crossing number of graphs with two small partition classes

A tripartite-circle drawing of a tripartite graph is a drawing in the plane, where each part of a vertex partition is placed on one of three disjoint circles, and the edges do not cross the circles. The tripartite-circle crossing number of a tripartite graph is the minimum number of edge crossings among all its tripartite-circle drawings. We determine the exact value of the tripartite-circle crossing number of $K_{a,b,n}$, where $a,b\leq 2$.Comment: 22 pages, 11 figures. Added new results and revised throughout. Originally appeared in arXiv:1910.06963v1, now removed from arXiv:1910.06963v

Cognitive Test Performance among Nondemented Elderly African Americans and Whites

We examined the neuropsychological test performance of a randomly selected community sample of English-speaking non-Hispanic African American and white elders in northern Manhattan. All participants were diagnosed as nondemented by a neurologist, whose assessment was made independent of neuropsychological test scores. African American elders obtained significantly lower scores on measures of verbal and nonverbal learning and memory, abstract reasoning, language, and visuospatial skill than whites. After using a stratified random sampling technique to match groups on years of education, many of the discrepancies became nonsignificant; however, significant ethnic group differences on measures of figure memory, verbal abstraction, category fluency, and visuospatial skill remained. Discrepancies in test performance of education-matched African Americans and whites could not be accounted for by occupational attainment or history of medical conditions such as hypertension and diabetes. These findings emphasize the importance of using culturally appropriate norms when evaluating ethnically diverse elderly for dementia

Managing expectations, rights, and duties in large-scale genomics initiatives: a European comparison

This article reports on the findings of an international workshop organised by the UK-France Genomics and Ethics Network (UK-FR GENE) in 2021. They focus specifically on how collection, storage and sharing of genomic data may pose challenges to established principles and values such as trust, confidentiality, and privacy in countries that have implemented, or are about to implement, large-scale national genomic initiatives. These challenges impact the relationships between patients/citizens and medicine/science, and on each party’s rights and duties towards each other. Our geographic scope of comparative analysis includes initiatives underway in England (Genomics England), France (Plan France Médecine Génomique) and Germany (German Human Genome-Phenome Archive). We discuss existing as well as future challenges raised by large-scale health data collection and management in each country. We conclude that the prospects of improving individualised patient healthcare as well as contributing to the scientific and research prosperity of any given nation engaged in health data collection, storage and processing are undeniable. However, we also attempt to demonstrate that biomedical data requires careful management, and transparent and accountable governance structures that are clearly communicated to patients/participants and citizens. Furthermore, when third parties partake as stakeholders, transparent consent protocols relative to data access and use come centre stage, and patient benefits must clearly outweigh commercial interests. Finally, any cross-border data transfer needs to be carefully managed to address incoherencies between regional, national, and supranational regulations and recommendations