A Mathematical Model of Human Dynamic Locomotion: Theoretical Bases of the Model

The most current models of dynamic locomotion involve the use of a simple or damped spring-mass system (McMahon and Green, 1979 and Blickhan, 1989). Each of these models uses rather simple approximations (point-like mass, and massless spring) of the complex human anatomy. They use the dynamic variables but neglect the control process completely. These models do not describe a realistic behavior of the system at some instant in time. For example, previous models have kept the system stiffness k, as a constant during the support phase. In reality, however, a complicated process depending on anatomy, posture, and muscle control gives rise to a wide variation in system stiffness as the takeoff leg moves over the support foot. Therefore, the problem faced in developing an analytical approach for coaching is to develop a mathematical model that accurately describes support phase mechanisms. The purpose of this study is to create a mathematical model that reflects all features that determine jump distance. In order to create a more realistic model, it has been necessary to derive equations of motion in a spring-mass system with stiffness k, as a function of time and posture. System stiffness k(t) was calculated from jump data collected using a Bertec force plate. Jump data was also used to test the accuracy of the model by comparing calculations to measurements of a 3D Motion Analysis System. The input parameters used for our model were the touchdown angle, the velocity at touchdown, the mass of the subject, the leg and foot length, and the system stiffness kW. We found the actual jump distance and the calculated distance in agreement. Also the calculated coordinates and velocities as functions of time match the measured data. The very first tests suggest a relative deviation of less than 5%. This refined model is more accurate than previous models of dynamic locomotion. It contains all the features necessary to accurately predict flight distance as a function of initial value parameters and support phase parameters. This model now becomes a tool for coaches to design individual performance in a heuristic manner

A Mathematical Model of Human Dynamic Locomotion: The Development and Application of the Model

Human walking is characterized by a progression of steps such that contact with the ground is never broken. More dynamic activities such as running, hopping, and jumping are characterized by a cycle that includes a phase of support as well as a ballistic flight phase. The objective of individuals engaged in dynamic locomotor activities is to produce and control desired movements in order to achieve a determined performance goal. The problem confronted by teachers, coaches, and trainers is to devise a systematic procedure based on scientific principles which can be used to evaluate motor skills. One solution to this problem is the traditional trial and error approach used by most coaches. In this study the authors have developed a systematic analytical approach using mathematical modelling as the tool. This tool permits the coach to systematically vary the input parameters thus moving toward an ideal technique for that individual without continually stressing the athlete. More specifically, the purposes of this presentation are to: 1) highlight the coaching demands that a realistic mathematical model of dynamic locomotion must meet and 2) show the development of a model that meets all features necessary to calculate the flight distance correctly given various input parameters. Therefore, the presentation will focus on: 1) features necessary for a realistic model of dynamic locomotion, which are anatomy, posture, dynamic variables, control processes, and stochastic, 2) the advantages and disadvantages of existing models, 3) the steps taken in developing our model, and 4) how our model can be used as a tool for coaches to evaluate and design individual performance in a heuristic manner

Association of individual-socioeconomic variation in quality-of-primary care with area-level service organisation: A multilevel analysis using linked data

Rationale, Aims and Objectives: Ensuring equitable access to primary care (PC) contributes to reducing differences in health related to people's socioeconomic circumstances. However, there is limited data on system-level factors associated with equitable access to high-quality PC. We examine whether individual-level socioeconomic variation in general practitioner (GP) quality-of-care varies by area-level organisation of PC services. Methods: Baseline data (2006–2009) from the Sax Institute's 45 and Up Study, involving 267,153 adults in New South Wales, Australia, were linked to Medicare Benefits Schedule claims and death data (to December 2012). Small area-level measures of PC service organisation were GPs per capita, bulk-billing (i.e., no copayment) rates, out-of-pocket costs (OPCs), rates of after-hours and chronic disease care planning/coordination services. Using multilevel logistic regression with cross-level interaction terms we quantified the relationship between area-level PC service characteristics and individual-level socioeconomic variation in need-adjusted quality-of-care (continuity-of-care, long-consultations, and care planning), separately by remoteness. Results: In major cities, more bulk-billing and chronic disease services and fewer OPCs within areas were associated with an increased odds of continuity-of-care—more so among people of high- than low education (e.g., bulk-billing interaction with university vs. no school certificate 1.006 [1.000, 1.011]). While more bulk-billing, after-hours services and fewer OPCs were associated with long consultations and care planning across all education levels, in regional locations alone, more after-hours services were associated with larger increases in the odds of long consultations among people with low- than high education (0.970 [0.951, 0.989]). Area GP availability was not associated with outcomes. Conclusions: In major cities, PC initiatives at the local level, such as bulk-billing and after-hours access, were not associated with a relative benefit for low- compared with high-education individuals. In regional locations, policies supporting after-hours access may improve access to long consultations, more so for people with low- compared with high-education

Management of COVID-19 in the community and the role of primary care: how the pandemic has shone light on a fragmented health system

[Extract] The Australian health care system is well regarded on the global stage in terms of the balance between investment in health care and outcomes delivered, particularly in terms of universal access, quality and safety.1 However, there is considerable fragmentation and poor coordination of care and communication between hospitals and primary care, which limits further improvement.2, 3 Geographical barriers, workforce shortages and issues relating to acceptability of services limit health care access for residents of rural, regional and remote communities, Aboriginal peoples and Torres Strait Islanders, and together with an inadequate focus on prevention, limit progress towards health equity. Australian responses to the coronavirus disease 2019 (COVID-19) pandemic through both public health responses and the acute health sector have been viewed as among the best in the world. Nevertheless, challenges in the structure, organisatIon and financing of the Australian health care system have been brought into stark relief by the evolution of responses to the pandemic

Building effective responses: An independent review of violence against women, domestic abuse and sexual violence services in Wales

Final published versionINTRODUCTION: Independent researchers from the Connect Centre for International Research on Interpersonal Violence based in the School of Social Work at the University of Central Lancashire were commissioned by the Welsh Government in 2013 to conduct research into violence against women, domestic abuse and sexual violence services in Wales. The research aimed to inform the forthcoming Ending Violence Against Women and Domestic Abuse (Wales) Bill, implementation of the legislation and future policy more generally, as well as informing future funding decisions. The remit of the review covers: Domestic abuse, including that experienced in Lesbian, Gay, Bisexual and Transgender (LGBT) relationships and elder abuse. Violence against women, including female genital mutilation (FGM), forced marriage and honour-based violence. Sexual violence including rape, sexual assault and harassment Sexual exploitation including prostitution and trafficking1 for sexual purposes. Services for women and men who are victims or perpetrators of violence against women, domestic abuse or sexual violence. The review does not encompass criminal justice services or housing services and, with the exception of prevention work, services for children and young people in Wales were also excluded from this study

lin-12 Notch functions in the adult nervous system of C. elegans

BACKGROUND: Notch signaling pathways are conserved across species and traditionally have been implicated in cell fate determination during embryonic development. Notch signaling components are also expressed postdevelopmentally in the brains of adult mice and Drosophila. Recent studies suggest that Notch signaling may play a role in the physiological, rather than developmental, regulation of neurons. Here, we investigate a new non-developmental role for Caenorhabditis elegans lin-12 Notch signaling in neurons regulating the spontaneous reversal rate during locomotion. RESULTS: The spontaneous reversal rate of C. elegans during normal locomotion is constant. Both lin-12 gain and loss of function mutant animals had significantly increased reversal rates compared to wild type controls. These defects were caused by lin-12 activity, because the loss of function defect could be rescued by a wild type lin-12 transgene. Furthermore, overexpression of lin-12 recapitulated the gain-of-function defect. Increasing or decreasing lin-12 activity in the postdevelopmental adult animal was sufficient to rapidly and reversibly increase reversals, thereby excluding a developmental role for lin-12. Although lin-12 is expressed in the vulval and somatic gonad lineages, we find that these tissues play no role in regulating reversal rates. In contrast, altering lin-12 activity specifically in the nervous system was sufficient to increase reversals. These behavioral changes require components of the canonical lin-12 signaling cascade, including the ligand lag-2 and the transcriptional effector lag-1. Finally, the C. elegans AMPA/kainate glutamate receptor homolog glr-1 shows strong genetic interactions with lin-12, suggesting that glr-1 and/or other glutamate gated channels may be targets of lin-12 regulation. CONCLUSION: Our results demonstrate a neuronal role for lin-12 Notch in C. elegans and suggest that lin-12 acutely regulates neuronal physiology to modulate animal behavior, without altering neuronal cell fate specification or neurite outgrowth. This is consistent with a role for Notch signaling in neurological disease with late onset symptoms