A qualitative investigation of the role of paediatric rehabilitation professionals in rural South Africa : rehabilitation professionals’ perspectives

PURPOSE : To investigate the role that rehabilitation professionals play in the rehabilitation of children with disabilities in the rural and under-resourced community of Giyani in South Africa. METHOD : A qualitative, exploratory and descriptive approach was used. Semi-structured face- to-face interviews were used to collect data from a convenient sample of eight rehabilitation professionals. Data were transcribed verbatim by two trained students and verified by the main researcher. An inductive approach to qualitative data analysis was used. In vivo and open coding were used to generate codes. RESULTS : Analysis of data resulted in 21 codes, 9 subcategories, 5 categories and 1 theme. The role of rehabilitation professionals was described in terms of the five categories which are to examine newborn babies and children at risk, support caregivers of children with disabilities, impart skills training for caregivers of children with disabilities, rehabilitate children with disabilities and conduct follow-ups in communities where the children with disabilities reside. CONCLUSION : The role that rehabilitation professionals play in the rural and under-resourced community of Giyani in South Africa is similar to the role played in high-income countries. The role that rehabilitation professionals play is not only focused on the child but also on the family.The article is based on a PhD thesis of D.M. C.E. was the promoter of the thesis and contributed towards the drafting of the article.The South African National Research Foundation (NRF), University of Pretoria and the South African Society of Physiotherapy.http://www.sajp.co.zaam2016Physiotherap

Causes of childhood disabilities in a rural South African community : caregivers' perspective

Childhood disabilities are conditions that affect or are likely to influence the development of children into adulthood. Childhood disabilities are common in both high-income as well as lowincome countries. UNICEF estimated that the number of children with disabilities below the age of 18 years was about 150 million. In low-income countries, the prevalence of childhood disability ranged between 0.4 and 12.7%. According to Census 2001, the prevalence of childhood disability in South Africa was between 2-3 %. It is commonly accepted in the literature that the aetiology of childhood disability is attributed to prenatal, perinatal and postnatal factors. However, disabilities within the African context have been associated with beliefs and spirituality retribution such as the “will of God or witchcraft”. The purpose of the study is to establish what the caregivers attribute as the cause of childhood disabilities in the rural community of South Africa. A qualitative, exploratory and descriptive approach was used to obtain the participants’ perspectives on the cause of childhood disability. Data were collected from caregivers of children with disabilities using individual face-to-face interviews (n=9) and three focus group discussions (n=10) at Nkhensani Hospital in Giyani, Limpopo Province, South Africa. Caregivers perceived “religious beliefs, other beliefs, biomedical factors and lifestyle and habits as possible causes of childhood disabilities. Even though belief-based-factors cannot be scientifically proven as potential causes of childhood disability, health care professionals should ensure at all times that they take into consideration the clients’ culture and beliefs during assessment and or treatment of the child.The National Research Foundation (NRF) and the University of Pretoria.http://www.journals.co.za/content/journal/ajpherd1am2017Physiotherap

A qualitative investigation of the role of paediatric rehabilitation professionals in rural South Africa : rehabilitation professionals’ perspectives

PURPOSE : To investigate the role that rehabilitation professionals play in the rehabilitation of children with disabilities in the rural and under-resourced community of Giyani in South Africa. METHOD : A qualitative, exploratory and descriptive approach was used. Semi-structured face- to-face interviews were used to collect data from a convenient sample of eight rehabilitation professionals. Data were transcribed verbatim by two trained students and verified by the main researcher. An inductive approach to qualitative data analysis was used. In vivo and open coding were used to generate codes. RESULTS : Analysis of data resulted in 21 codes, 9 subcategories, 5 categories and 1 theme. The role of rehabilitation professionals was described in terms of the five categories which are to examine newborn babies and children at risk, support caregivers of children with disabilities, impart skills training for caregivers of children with disabilities, rehabilitate children with disabilities and conduct follow-ups in communities where the children with disabilities reside. CONCLUSION : The role that rehabilitation professionals play in the rural and under-resourced community of Giyani in South Africa is similar to the role played in high-income countries. The role that rehabilitation professionals play is not only focused on the child but also on the family.The article is based on a PhD thesis of D.M. C.E. was the promoter of the thesis and contributed towards the drafting of the article.The South African National Research Foundation (NRF), University of Pretoria and the South African Society of Physiotherapy.http://www.sajp.co.zaam2016Physiotherap

Psychometric validation of the reintegration to normal living index in people living with spinal cord injuries

The evaluation of rehabilitation outcomes requires measurement instruments that are valid and reliable, and have been psychometrically tested in the context of a particular population. The purpose of this study was to psychometrically test the validity and reliability of the Reintegration to Normal Living Index (RNLI) as a measure of community reintegration in a population of community-dwelling people living with spinal cord injury (PLWSCI) in South Africa. The study was a cross-sectional, involving community dwelling people living with SCI (PLWSCI), who had been discharged from inpatient rehabilitation at for at least two years. RNLI data collected from 160 PLWSCI were subjected to factor analysis and tested for reliability using chronbach’s alpha. Cronbach’s alpha for the RNLI instrument was 0.97 (ICC 95% CI: 0.97 – 0.98), indicating an excellent reliability coefficient. A single -factor structure emerged from principal components analysis, indicating that there is only one factor structure for the RNLI in this population of PLWSCI. The content, construct, convergent and discriminate validity of the instrument were established. The results of this study support the reliability and factorial validity of the RNLI as a measure of community reintegration for PLWSCI. The RNLI is therefore a valuable outcome measure and should be extended to other SCI rehabilitation studies in South Africa.This paper reports on part of a PhD study conducted by DJ Mothabeng at the University of Pretoria, supervised by Dr CA Eksteen and Professor M Westaway.The study was supported by grants from the School of Health Care Sciences at the University of Pretoria, and the Research foundation of the South African Society of Physiotherapy.http://www.sajp.co.za/index.php/sajpam201

A cross-sectional survey and cross-sectional clinical trial to determine the prevalence and management of eye movement disorders and vestibular dysfunction in post-stroke patients in the sub-acute phase : protocol

INTRODUCTION: Visual impairment, specifically eye movement disorders and vestibular dysfunction may have a negative influence on the functional recovery in post-stroke patients. This type of sensory dysfunction may further be associated with poor functional outcome in patients' post-stroke. METHODS: In phase 1, a cross-sectional survey (n = 100) will be conducted to determine the prevalence of eye movement disorders and vestibular dysfunction in patients who sustained a stroke. A cross-sectional clinical trial (n = 60) will be conducted during phase 2 of the study to determine the effect of the combination of vestibular rehabilitation therapy (VRT) and visual scanning exercises (VSE) (experimental group) integrated with task-specific activities compared with the effect of task-specific activities as an intervention (control group) on patients who present with eye movement impairment and central vestibular dysfunction post-stroke. An audiologist will assess (a) visual acuity (static and dynamic), (b) nystagmus, (c) saccadic eye movements, (d) smooth pursuit eye movements, (e) vestibulo-ocular reflex, and (f) saccular, utricular, and vestibular nerve function. An independent physiotherapist will assess (1) cognitive function, (2) residual oculomotor visual performance, (3) visual-perceptual system, (4) functional balance, (5) gait, (6) functional ability, (7) presence of anxiety and/or depression, and (8) level of participation in physical activity. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Ethics Committee of the Faculty of Health Sciences at the University of Pretoria (UP) (374/2015). The study will be submitted as fulfillment for the PhD degree at UP. Dissemination will include submission to peer-reviewed professional journals and presentation at congresses. Training of rehabilitation team members on the integration of VSE and VRT into task-specific activities in rehabilitation will be done if the outcome of the experimental group's functional performance is clinically and statistically significantly better than the control group on the Barthel Index. TRIAL REGISTRATION: Pan African Clinical Trials Registry (PACTR201509001223262).The principal researcher received a National Research Foundation Innovation Doctoral scholarship for 2016 and funding from the South African Society of Physiotherapy’s Research Foundation (VAN180).http://journal.frontiersin.org/journal/neurologyam2016PhysiotherapySpeech-Language Pathology and Audiolog

A cross-sectional survey and cross-sectional clinical trial to determine the prevalence and management of eye movement disorders and vestibular dysfunction in post-stroke patients in the sub-acute phase : protocol

INTRODUCTION: Visual impairment, specifically eye movement disorders and vestibular dysfunction may have a negative influence on the functional recovery in post-stroke patients. This type of sensory dysfunction may further be associated with poor functional outcome in patients' post-stroke. METHODS: In phase 1, a cross-sectional survey (n = 100) will be conducted to determine the prevalence of eye movement disorders and vestibular dysfunction in patients who sustained a stroke. A cross-sectional clinical trial (n = 60) will be conducted during phase 2 of the study to determine the effect of the combination of vestibular rehabilitation therapy (VRT) and visual scanning exercises (VSE) (experimental group) integrated with task-specific activities compared with the effect of task-specific activities as an intervention (control group) on patients who present with eye movement impairment and central vestibular dysfunction post-stroke. An audiologist will assess (a) visual acuity (static and dynamic), (b) nystagmus, (c) saccadic eye movements, (d) smooth pursuit eye movements, (e) vestibulo-ocular reflex, and (f) saccular, utricular, and vestibular nerve function. An independent physiotherapist will assess (1) cognitive function, (2) residual oculomotor visual performance, (3) visual-perceptual system, (4) functional balance, (5) gait, (6) functional ability, (7) presence of anxiety and/or depression, and (8) level of participation in physical activity. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Ethics Committee of the Faculty of Health Sciences at the University of Pretoria (UP) (374/2015). The study will be submitted as fulfillment for the PhD degree at UP. Dissemination will include submission to peer-reviewed professional journals and presentation at congresses. Training of rehabilitation team members on the integration of VSE and VRT into task-specific activities in rehabilitation will be done if the outcome of the experimental group's functional performance is clinically and statistically significantly better than the control group on the Barthel Index. TRIAL REGISTRATION: Pan African Clinical Trials Registry (PACTR201509001223262).The principal researcher received a National Research Foundation Innovation Doctoral scholarship for 2016 and funding from the South African Society of Physiotherapy’s Research Foundation (VAN180).http://journal.frontiersin.org/journal/neurologyam2016PhysiotherapySpeech-Language Pathology and Audiolog

Direct Optimal Mapping Image Power Spectrum and its Window Functions

The key to detecting neutral hydrogen during the epoch of reionization (EoR) is to separate the cosmological signal from the dominating foreground radiation. We developed direct optimal mapping (Xu et al. 2022) to map interferometric visibilities; it contains only linear operations, with full knowledge of point spread functions from visibilities to images. Here we present an FFT-based image power spectrum and its window functions based on direct optimal mapping. We use noiseless simulation, based on the Hydrogen Epoch of Reionization Array (HERA) Phase I configuration, to study the image power spectrum properties. The window functions show $<10^{-11}$ power leakage from the foreground-dominated region into the EoR window; the 2D and 1D power spectra also verify the separation between the foregrounds and the EoR. Furthermore, we simulated visibilities from a $uv$-complete array and calculated its image power spectrum. The result shows that the foreground--EoR leakage is further suppressed below $10^{-12}$, dominated by the tapering function sidelobes; the 2D power spectrum does not show signs of the horizon wedge. The $uv$-complete result provides a reference case for future 21cm cosmology array designs.Comment: Submitted to Ap

What does an interferometer really measure? Including instrument and data characteristics in the reconstruction of the 21cm power spectrum

Combining the visibilities measured by an interferometer to form a cosmological power spectrum is a complicated process in which the window functions play a crucial role. In a delay-based analysis, the mapping between instrumental space, made of per-baseline delay spectra, and cosmological space is not a one-to-one relation. Instead, neighbouring modes contribute to the power measured at one point, with their respective contributions encoded in the window functions. To better understand the power spectrum measured by an interferometer, we assess the impact of instrument characteristics and analysis choices on the estimator by deriving its exact window functions, outside of the delay approximation. Focusing on HERA as a case study, we find that observations made with long baselines tend to correspond to enhanced low-k tails of the window functions, which facilitate foreground leakage outside the wedge, whilst the choice of bandwidth and frequency taper can help narrow them down. With the help of simple test cases and more realistic visibility simulations, we show that, apart from tracing mode mixing, the window functions can accurately reconstruct the power spectrum estimator of simulated visibilities. We note that the window functions depend strongly on the chromaticity of the beam, and less on its spatial structure - a Gaussian approximation, ignoring side lobes, is sufficient. Finally, we investigate the potential of asymmetric window functions, down-weighting the contribution of low-k power to avoid foreground leakage. The window functions presented in this work correspond to the latest HERA upper limits for the full Phase I data. They allow an accurate reconstruction of the power spectrum measured by the instrument and can be used in future analyses to confront theoretical models and data directly in cylindrical space.Comment: 18 pages, 18 figures, submitted to MNRAS. Comments welcome

Characterization Of Inpaint Residuals In Interferometric Measurements of the Epoch Of Reionization

Radio Frequency Interference (RFI) is one of the systematic challenges preventing 21cm interferometric instruments from detecting the Epoch of Reionization. To mitigate the effects of RFI on data analysis pipelines, numerous inpaint techniques have been developed to restore RFI corrupted data. We examine the qualitative and quantitative errors introduced into the visibilities and power spectrum due to inpainting. We perform our analysis on simulated data as well as real data from the Hydrogen Epoch of Reionization Array (HERA) Phase 1 upper limits. We also introduce a convolutional neural network that capable of inpainting RFI corrupted data in interferometric instruments. We train our network on simulated data and show that our network is capable at inpainting real data without requiring to be retrained. We find that techniques that incorporate high wavenumbers in delay space in their modeling are best suited for inpainting over narrowband RFI. We also show that with our fiducial parameters Discrete Prolate Spheroidal Sequences (DPSS) and CLEAN provide the best performance for intermittent ``narrowband'' RFI while Gaussian Progress Regression (GPR) and Least Squares Spectral Analysis (LSSA) provide the best performance for larger RFI gaps. However we caution that these qualitative conclusions are sensitive to the chosen hyperparameters of each inpainting technique. We find these results to be consistent in both simulated and real visibilities. We show that all inpainting techniques reliably reproduce foreground dominated modes in the power spectrum. Since the inpainting techniques should not be capable of reproducing noise realizations, we find that the largest errors occur in the noise dominated delay modes. We show that in the future, as the noise level of the data comes down, CLEAN and DPSS are most capable of reproducing the fine frequency structure in the visibilities of HERA data.Comment: 26 pages, 18 figure

Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array

Motivated by the desire for wide-field images with well-defined statistical properties for 21cm cosmology, we implement an optimal mapping pipeline that computes a maximum likelihood estimator for the sky using the interferometric measurement equation. We demonstrate this direct optimal mapping with data from the Hydrogen Epoch of Reionization (HERA) Phase I observations. After validating the pipeline with simulated data, we develop a maximum likelihood figure-of-merit for comparing four sky models at 166MHz with a bandwidth of 100kHz. The HERA data agree with the GLEAM catalogs to <10%. After subtracting the GLEAM point sources, the HERA data discriminate between the different continuum sky models, providing most support for the model of Byrne et al. 2021. We report the computation cost for mapping the HERA Phase I data and project the computation for the HERA 320-antenna data; both are feasible with a modern server. The algorithm is broadly applicable to other interferometers and is valid for wide-field and non-coplanar arrays.Comment: 16 pages, 10 figures, 2 tables, published on Ap