Browsing Faculty of Natural Sciences by Title
Now showing items 1984-2003 of 2571
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Records of ctenophores from South Africa
(PeerJ Inc., 2021)Although ctenophores can be conspicuous components of the plankton in coastal marine ecosystems, only six species have been formally described from around South Africa. Using photographs from local community scientists, ... -
Recovery and recycling of valuable metals from spent lithium-ion batteries: A comprehensive review and analysis
(MDPI, 2023)The recycling of spent lithium-ion batteries (Li-ion Batteries) has drawn a lot of interest in recent years in response to the rising demand for the corresponding high-value metals and materials and the mounting concern ... -
Recursion relations for gravitational lensing
(Springer Nature, 2019)The weak gravitational lensing formalism can be extended to the strong lensing regime by integrating a nonlinear version of the geodesic deviation equation. The resulting ‘roulette’ expansion generalises the notion of ... -
Redshift evolution of galaxy group X-ray properties in the SIMBA simulations
(Oxford University Press, 2023)We examine the evolution of intragroup gas rest-frame X-ray scaling relations for group-sized haloes (M500 = 1012.3–1015 M) in the SIMBA galaxy formation simulation. X-ray luminosity LX versus M500 shows increasing deviation ... -
The redshift evolution of the baryonic Tully-Fisher relation in SIMBA
(Oxford university press, 2021)The baryonic Tully–Fisher relation (BTFR) is an important tool for constraining galaxy evolution models. As 21-cm HI emission studies have been largely restricted to low redshifts, the redshift evolution of the BTFR is ... -
Reef benthos of Seychelles - A field guide
(Pensoft Publishers, 2021)During the 2019 First Descent: Seychelles Expedition, shallow and deep reef ecosystems of the Seychelles Outer Islands were studied by deploying a variety of underwater technologies to survey their benthic flora and fauna. ... -
Refinement of locality data for FitzSimons’ Garter Snake Elapsoidea sundevallii fitzsimonsi Loveridge, 1948 provides a better estimation of its distribution
(Herpetology Notes, 2020)Foundational data on species taxonomy, distribution and ecology forms the basis of assessing species for their conservation status. For African reptiles, distributional data are sorely lacking for many taxa, sometimes ... -
Reflecting on the current scenario and forecasting the future demand for medical doctors in South Africa up to 2030: towards equal representation of women
(Springer Nature, 2021)Increasing feminization of medical professions is well-acknowledged. However, this does not always equate to equitable representation of women within medicine, regarding their socio-demographic indicators, regions, sectors ... -
Reflection on three years of rural wireless Internet Protocol communication
(Telkom, 2007)This paper reports on three years of research and fieldwork with a rural wireless Internet Protocol communication project. We built a long-range WiFi network and custom communication software to support a rural telehealth ... -
Reflectivity of VUV-sensitive silicon photomultipliers in liquid Xenon
(IOP Publishing, 2021)Silicon photomultipliers are regarded as a very promising technology for nextgeneration, cutting-edge detectors for low-background experiments in particle physics. This work presents systematic reflectivity studies of ... -
Regional rainfall prediction using support vector machine classification of large-scale precipitation maps
(Institute of Electrical and Electronics Engineers Inc., 2020)Rainfall prediction helps planners anticipate potential social and economic impacts produced by too much or too little rain. This research investigates a class-based approach to rainfall prediction from 1-30 days in advance. ... -
Regulation of AKT/AMPK signaling, autophagy and mitigation of apoptosis in Rutin-pretreated SH-SY5Y cells exposed to MPP+
(Springer Nature, 2021)Accumulating evidence suggest that apoptosis, autophagy and dysregulation of signaling pathways are common mechanisms involved in Parkinson’s disease (PD) pathogenesis, and thus development of therapeutic agents targeting ... -
Regulatory registration timelines of generic medicines in South Africa: Assessment of the performance of SAHPRA between 2011 and 2022
(Springer, 2023)Various regulatory authorities are experiencing backlogs of applications which result in delayed access to medicines for patients. The objective of this study is to critically assess the registration process utilised by ... -
The relation between the diffuse X-ray luminosity and the radio power of the central AGN in galaxy groups
(Oxford University Press, 2020)Our understanding of how active galactic nucleus feedback operates in galaxy clusters has improved in recent years owing to large efforts in multiwavelength observations and hydrodynamical simulations. However, it is much ... -
The Relationship between Cadmium Toxicity and the Modulation of Epigenetic Traits in Plants
(International Journal of Molecular Sciences, 2021-06)Elevated concentrations of heavy metals such as cadmium (Cd) have a negative impact on staple crop production due to their ability to elicit cytotoxic and genotoxic effects on plants. In order to understand the relationship ... -
The relationship between client dissatisfaction and contraceptive discontinuation among urban family planning clients in three sub-Saharan African countries
(Public Library of Science, 2022)Although researchers and practitioners have suggested that the quality of family planning services impacts contraceptive discontinuation, establishing a causal relationship has been challenging, primarily due to data ... -
The relationship between household sanitation and women’s experience of menstrual hygiene: Findings from a cross-sectional survey in Kaduna State, Nigeria
(MDPI, 2018)Global efforts to improve sanitation have emphasized the needs of women and girls. Managing menstruation is one such need, yet there is scarce research capturing current practices. This study investigated the relationships ... -
The relationship between seminal leukocytes, oxidative status in the ejaculate, and apoptotic markers in human spermatozoa
(Taylor & Francis, 2013)The aim of this study was to investigate the relationship between seminal leukocytes, reactive oxygen species (ROS) production in the ejaculate, and markers of apoptosis in human spermatozoa. Semen samples were collected ... -
Relative contribution of various chronic diseases and multi-morbidity to potential disability among Dutch elderly
(2018, 2018)BACKGROUND: The amount of time spent living with disease greatly influences elderly people’s wellbeing, disability and healthcare costs, but differs by disease, age and sex. METHODS: We assessed how various single and ... -
Relative homotopy in relational structures
(Cambridge University Press, 2018)The homotopy groups of a finite partially ordered set (poset) can be described entirely in the context of posets, as shown in a paper by B. Larose and C. Tardif. In this paper we describe the relative version of such a ...