Faculty of Natural Sciences: Recent submissions
Now showing items 941-960 of 2639
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Oxidative Stress, Ageing and Methods of Seed Invigoration: An Overview and Perspectives
(MDPI, 2021)The maintenance of seed quality during the long-term conservation of plant genetic resources is crucial for averting the projected food crises that are linked to the changing climate and rising world population. However, ... -
Multifunctional Gold Nanoparticles for Improved Diagnostic and Therapeutic Applications: A Review
(Springer Open, 2021)The medical properties of metals have been explored for centuries in traditional medicine for the treatment of infections and diseases and still practiced to date. Platinum-based drugs are the first class of metal-based ... -
SKAO HI intensity mapping: blind foreground subtraction challenge
(University of the Western Cape, 2022)Neutral Hydrogen Intensity Mapping (H I IM) surveys will be a powerful new probe of cosmology. However, strong astrophysical foregrounds contaminate the signal and their coupling with instrumental systematics further ... -
MIGHTEE: Total intensity radio continuum imaging and the COSMOS/XMM-LSS Early Science fields
(University of the Western Cape, 2022)MIGHTEE is a galaxy evolution survey using simultaneous radio continuum, spectropolarimetry, and spectral line observations from the South African MeerKAT telescope. When complete, the survey will image ∼20 deg2 over the ... -
The Copernican principle in light of the latest cosmological data
(University of the Western Cape, 2022)We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle (CP) rather than assuming it a priori. We consider the CDM model endowed with ... -
The MeerKAT Galaxy Cluster Legacy Survey: Survey overview and highlights
(University of the Western Cape, 2022)MeerKAT’s large number (64) of 13.5 m diameter antennas, spanning 8 km with a densely packed 1 km core, create a powerful instrument for wide-area surveys, with high sensitivity over a wide range of angular scales. The ... -
Automated detection of antenna malfunctions in large-n interferometers: A case study with the hydrogen epoch of reionization array
(2022)We present a framework for identifying and flagging malfunctioning antennas in large radio interferometers. We outline two distinct categories of metrics designed to detect outliers along known failure modes of large ... -
Validation of the HERA Phase I Epoch of Reionization 21 cm Power Spectrum Software Pipeline
(The American Astronomical Society., 2022)We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in ... -
HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization
(The American Astronomical Society., 2022)Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models ... -
Superhorizon Perturbations: A Possible Explanation of the Hubble–Lemaître Tension and the Large-scale Anisotropy of the Universe.
(The American Astronomical Society., 2022)Current cosmological observations point to a serious discrepancy between the observed Hubble parameter obtained using direct versus cosmic microwave background radiation measurements. Besides this so-called Hubble– Lemaître ... -
Biomarkers, stable carbon isotope, and trace element distribution of source rocks in the Orange Basin, South Africa: implications for paleoenvironmental reconstruction, provenance, and tectonic setting
(2021)Aptian to Campanian sediments from the Western ofshore to Central Orange Basin were studied by integrating molecular geochemistry, inorganic and isotopic studies to recognize their geochemical characteristics via the ... -
Evidence from the Vredefort Granophyre Dikes points to crustal relaxation following basin-size impact cratering
(Academic Press Inc., 2021-11-24)The timescale of the modification stage of basin-sized impact structures is not well understood. Owing to ca. 10 km of erosion since its formation, the Vredefort impact structure, South Africa, is an ideal testing ground ... -
A deep radio view of the evolution of the cosmic star formation rate density from a stellar-mass-selected sample in VLA-COSMOS
(Royal Astronomical Society, 2022)We present the 1.4 GHz radio luminosity functions (RLFs) of galaxies in the Cosmic Evolution Survey (COSMOS) field, measured above and below the 5σ detection threshold, using a Bayesian model-fitting technique. The radio ... -
Analysis and exploitation of landforms for improved optimisation of camera based wildfire detection systems
(Springer, 2021)Tower-mounted camera-based wildfire detection systems provide an effective means of early forest fire detection. Historically, tower sites have been identified by foresters and locals with intimate knowledge of the terrain ... -
A mixed-methods study exploring women’s perceptions of terminology surrounding fertility and menstrual regulation in Côte d’Ivoire and Nigeria
(BMC, 2021)Women use various terms when discussing the management of their fertility and menstrual irregularities and may interpret the experience of ending a possible pregnancy in nuanced ways, especially when their pregnancy status ... -
Isolation and characterization of strain exiguobacterium sp. Krl4, a producer of bioactive secondary metabolites from a Tibetan glacier
(MPDI, 2021)Extremophilic microorganisms represent a unique source of novel natural products. Among them, cold adapted bacteria and particularly alpine microorganisms are still underexplored. Here, we describe the isolation and ... -
Factors influencing the awareness and adoption of borehole-garden permaculture in Malawi: Lessons for the promotion of sustainable practices
(MPDI, 2021)Using wastewater accumulating around rural waterpoints to irrigate community gardens, borehole-garden permaculture (BGP) presents a method of sustainable water management. BGP also presents public health benefits through ... -
Three novel bacteria associated with two centric diatom species from the Mediterranean Sea, Thalassiosira rotula and Skeletonema marinoi
(MPDI, 2021)Diatoms are a successful group of microalgae at the base of the marine food web. For hundreds of millions of years, they have shared common habitats with bacteria, which favored the onset of interactions at different ... -
Abundance of no3 derived organo-nitrates and their importance in the atmosphere
(MPDI, 2021)The chemistry of the nitrate radical and its contribution to organo-nitrate formation in the troposphere has been investigated using a mesoscale 3-D chemistry and transport model, WRFChem-CRI. The model-measurement ... -
Article comparing three countries’ higher education students’ cyber related perceptions and behaviours during COVID-19
(MPDI, 2021): In 2020, a global pandemic led to lockdowns, and subsequent social and business restrictions. These required overnight implementation of emergency measures to permit continued functioning of vital industries. Digital ...