78 research outputs found
The effect of milk yield on some reproductive parameters of the Elsenburg Holstein and Jersey herds
(South African J of Animal Science, 2000, 30, Supplement 1: 34-35
Network structure of vertebrate scavenger assemblages at the global scale: drivers and ecosystem functioning implications
publishedVersio
Risk factors for Coronavirus Disease 2019 (COVID-19) death in a population cohort study from the Western Cape Province, South Africa
BACKGROUND. Risk factors for coronavirus disease 2019 (COVID-19) death in sub-Saharan Africa and the effects of human immunodeficiency
virus (HIV) and tuberculosis on COVID-19 outcomes are unknown.
METHODS. We conducted a population cohort study using linked data from adults attending public-sector health facilities in the
Western Cape, South Africa. We used Cox proportional hazards models, adjusted for age, sex, location, and comorbidities, to examine
the associations between HIV, tuberculosis, and COVID-19 death from 1 March to 9 June 2020 among (1) public-sector “active
patients” (≥1 visit in the 3 years before March 2020); (2) laboratory-diagnosed COVID-19 cases; and (3) hospitalized COVID-19
cases. We calculated the standardized mortality ratio (SMR) for COVID-19, comparing adults living with and without HIV using
modeled population estimates.
RESULTS. Among 3 460 932 patients (16% living with HIV), 22 308 were diagnosed with COVID-19, of whom 625 died. COVID-
19 death was associated with male sex, increasing age, diabetes, hypertension, and chronic kidney disease. HIV was associated with
COVID-19 mortality (adjusted hazard ratio [aHR], 2.14; 95% confidence interval [CI], 1.70–2.70), with similar risks across strata of
viral loads and immunosuppression. Current and previous diagnoses of tuberculosis were associated with COVID-19 death (aHR,
2.70 [95% CI, 1.81–4.04] and 1.51 [95% CI, 1.18–1.93], respectively). The SMR for COVID-19 death associated with HIV was 2.39
(95% CI, 1.96–2.86); population attributable fraction 8.5% (95% CI, 6.1–11.1).
CONCLUSIONS. While our findings may overestimate HIV- and tuberculosis-associated COVID-19 mortality risks due to residual
confounding, both living with HIV and having current tuberculosis were independently associated with increased COVID-19 mortality.
The associations between age, sex, and other comorbidities and COVID-19 mortality were similar to those in other settings.The Western Cape Provincial Health Data Centre from the Western Cape Department of Health, the US National Institutes for Health (grant numbers R01 HD0804, the Bill and Melinda Gates Foundation, the United States Agency for International Development and the Wellcome Trust.https://academic.oup.com/cid/am2023Veterinary Tropical Disease
The SARAO MeerKAT 1.3 GHz Galactic Plane Survey
We present the SARAO MeerKAT Galactic Plane Survey (SMGPS), a 1.3 GHz continuum survey of almost half of the Galactic Plane (251○ ≤l ≤ 358○ and 2○ ≤l ≤ 61○ at |b| ≤ 1
5). SMGPS is the largest, most sensitive and highest angular resolution 1 GHz survey of the Plane yet carried out, with an angular resolution of 8″ and a broadband RMS sensitivity of ∼10–20 μJy beam−1. Here we describe the first publicly available data release from SMGPS which comprises data cubes of frequency-resolved images over 908–1656 MHz, power law fits to the images, and broadband zeroth moment integrated intensity images. A thorough assessment of the data quality and guidance for future usage of the data products are given. Finally, we discuss the tremendous potential of SMGPS by showcasing highlights of the Galactic and extragalactic science that it permits. These highlights include the discovery of a new population of non-thermal radio filaments; identification of new candidate supernova remnants, pulsar wind nebulae and planetary nebulae; improved radio/mid-IR classification of rare Luminous Blue Variables and discovery of associated extended radio nebulae; new radio stars identified by Bayesian cross-matching techniques; the realisation that many of the largest radio-quiet WISE H II region candidates are not true H II regions; and a large sample of previously undiscovered background H I galaxies in the Zone of Avoidance
The MeerKAT Galaxy Cluster Legacy Survey: I. Survey overview and highlights
Please abstract in the article.The South African Radio Astronomy Observatory (SARAO), the National Research Foundation (NRF), the National Radio Astronomy Observatory, US National Science Foundation, the South African Research Chairs Initiative of the DSI/NRF, the SARAO HCD programme, the South African Research Chairs Initiative of the Department of Science and Innovation.http://www.aanda.orghj2022Physic
DSP based controller for high dynamic bandwidth power electronic applications
Recent developments in power electronics and control have led to a wide variety of control algorithms for drive and power quality applications. These new control algorithms are computationally intensive and are more practical to implement on microprocessor based controllers. This field of study is still heavily under investigation with many new algorithms being developed. A flexible controller capable of handling these algorithms in real time is therefore necessary. This paper presents such a digital signal processing based controller and implements an active power filter to show the operation of the new controller.Conference Pape
The identification of management-process critical success factors that will achieve competitiveness and sustainable growth for South Africa as tourist destination
Existing destination competitiveness models do not clearly identify the strategic
relationships between the critical factors and how they can be integrated for sustainable
growth and competitive advantage.
Against this background, this article focuses on the development and testing of a
destination competitiveness model that can be used to identify and integrate critical
success factors for a tourism destination.
The destination competitiveness model that is presented makes provision for the
identification and integration of critical success factors within four strategic perspectives,
namely, sustainable growth, the customer, destination management processes, and
learning and growth.
To test the model, a survey was undertaken among the primary tourism stakeholders in
South Africa involved in attracting and servicing international tourists. This survey
was used to identify critical success factors in the destination management processes that
could have the greatest impact on customer satisfaction and the achievement of
sustainable growth objectives. Specific conclusions are made and key actions
recommended on the basis of the results obtained
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