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We generalize the method of computing functional determinants with a single excluded zero eigenvalue developed by McKane and Tarlie to differential operators with multiple zero eigenvalues. We derive general formulas for such functional determinants of $r\times r$ matrix second order differential operators O with $0 < n \leqslant 2r$ linearly independent zero modes. We separately discuss the cases of the homogeneous Dirichlet boundary conditions, when the number of zero modes cannot exceed r, and the case of twisted boundary conditions, including the periodic and anti-periodic ones, when the number of zero modes is bounded above by 2r. In all cases the determinants with excluded zero eigenvalues can be expressed only in terms of the n zero modes and other $r-n$ or $2r-n$ (depending on the boundary conditions) solutions of the homogeneous equation $O h=0$ , in the spirit of Gel'fand–Yaglom approach. In instanton calculations, the contribution of the zero modes is taken into account by introducing the so-called collective coordinates. We show that there is a remarkable cancellation of a factor (involving scalar products of zero modes) between the Jacobian of the transformation to the collective coordinates and the functional fluctuation determinant with excluded zero eigenvalues. This cancellation drastically simplifies instanton calculations when one uses our formulas.
ABSTRACT Purpose: To gain insight into determinants of physical activity in wheelchair users with spinal cord injury or lower limb amputation, from the perspective of both wheelchair users and rehabilitation professionals. Methods: Seven focus groups were conducted: five with wheelchair users (n=25) and two with rehabilitation professionals (n¼11). The transcripts were analysed using a sequential coding strategy, in which the reported determinants of physical activity were categorized using the Physical Activity for people with a Disability (PAD) model. Results: Reported personal determinants of physical activity were age, general health status, stage of life, demotivation due to difficulty burning calories, available time and energy, balance in daily life, attitude, and history of a physically active lifestyle. Reported environmental determinants were professional guidance, inconvenient exercise times, accessibility of facilities, costs, transportation difficulties, equipment difficulties, and social support. Conclusions: Important, changeable determinants of physical activity that might be influenced in future lifestyle interventions for wheelchair users are: balance in daily life leading to more time and energy to exercise, attitude towards physical activity, professional guidance, accessibility of facilities (providing information on how and where to find accessible facilities), and social support (learning how to get this)
Background: Successful implementation of multifactorial fall prevention interventions (FPIs) is essential to reduce increasing fall rates in communitydwelling older adults. However, implementation often fails due to the complex context of the community involving multiple stakeholders within and across settings, sectors, and organizations. As there is a need for a better understanding of the occurring context-related challenges, the current scoping review purposes to identify what contextual determinants (i.e., barriers and facilitators) influence the implementation of FPIs in the community. Methods: A scoping reviewwas performed using the Arksey andO’Malley framework. First, electronic databases (Pubmed, CINAHL, SPORTDiscus, PsycINFO) were searched. Studies that identified contextual determinants that influence the implementation of FPIs in the community were included. Second, to both validate the findings from the literature and identify complementary determinants, health and social care professionals were consulted during consensus meetings (CMs) in four districts in the region of Utrecht, the Netherlands. Data were analyzed following a directed qualitative content analysis approach, according to the 39 constructs of the Consolidated Framework for Implementation Research. Results: Fourteen relevant studies were included and 35 health and social care professionals (such as general practitioners, practice nurses, and physical therapists) were consulted during four CMs. Directed qualitative content analysis of the included studies yielded determinants within 35 unique constructs operating as barriers and/or facilitators. The majority of the constructs (n = 21) were identified in both the studies and CMs, such as “networks and communications”, “formally appointed internal implementation leaders”, “available resources” and “patient needs and resources”. The other constructs (n = 14) were identified only in the . Discussion: Findings in this review show that awide array of contextual determinants are essential in achieving successful implementation of FPIs in the community. However, some determinants are considered important to address, regardless of the context where the implementation occurs. Such as accounting for time constraints and financial limitations, and considering the needs of older adults. Also, broad cross-sector collaboration and coordination are required in multifactorial FPIs. Additional context analysis is always an essential part of implementation efforts, as contexts may differ greatly, requiring a locally tailored approach.