Cissus rotundifolia (Forssk.) Vahl. (Vitaceae) is a wild plant that is commonly used by communities from rural areas as a food and medicine. There are limited studies on the phytochemical composition ...and the impact of soil quality on the elemental distribution in this plant. In this study, we report a phytochemical analysis to identify the phytocompounds responsible for the reported biological activities of C. rotundifolia. We also examined the impact of soil quality on elemental uptake by the edible parts of C. rotundifolia collected from eight geographical locations in KwaZulu-Natal (South Africa) to assess the nutritional benefits and potential heavy metal toxicities. Three secondary metabolites (stigmasterol, β-sitosterol, and pheophytin a) were isolated, and their structures were characterised by high-resolution mass spectrometry and nuclear magnetic resonance data. The plant was found to contribute adequately to the recommended dietary allowances for essential nutrients without exceeding tolerable upper intake limits and with low concentrations of toxic heavy metals. The average concentrations of microelements in the edible parts were found to be in decreasing order of Fe>Mn>Se>Zn>Cu>Cr>Ni>Co. The bioaccumulation factors indicate that the plant controls the uptake of metals from the soil and would make a good indicator and biological monitor for cadmium toxicity. However, a health risk assessment exposed carcinogenic risks on regular consumption of the plant obtained from sites close to pollution sources, such as roads and landfills. The findings from this study show the synergies when consuming medicinal plants and provide evidence for C. rotundifolia as a nutraceutical.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The fragmentation of the Isoscalar Giant Quadrupole Resonance (ISGQR) in 40Ca has been investigated in high energy-resolution experiments using proton inelastic scattering at Ep=200 MeV. Fine ...structure is observed in the region of the ISGQR and its characteristic energy scales are extracted from the experimental data by means of a wavelet analysis. The experimental scales are well described by Random Phase Approximation (RPA) and second-RPA calculations with an effective interaction derived from a realistic nucleon–nucleon interaction by the Unitary Correlation Operator Method (UCOM). In these results characteristic scales are already present at the mean-field level pointing to their origination in Landau damping, in contrast to the findings in heavier nuclei and also to SRPA calculations for 40Ca based on phenomenological effective interactions, where fine structure is explained by the coupling to two-particle–two-hole (2p–2h) states.
The phenomenon of fine structure of the Isoscalar Giant Quadrupole Resonance (ISGQR) has been studied with high energy-resolution proton inelastic scattering at iThemba LABS in the chain of stable ...even-mass Nd isotopes covering the transition from spherical to deformed ground states. A wavelet analysis of the background-subtracted spectra in the deformed 146, 148, 150Nd isotopes reveals characteristic scales in correspondence with scales obtained from a Skyrme RPA calculation using the SVmas10 parameterization. A semblance analysis shows that these scales arise from the energy shift between the main fragments of the K=0,1 and K=2 components.
Background: South Africa is characterised by high levels of biodiversity and species endemism alongside critical levels of socio-economic vulnerability, demonstrating potential for ...conservation practices that provide both environmental and social benefits. It is argued that communitybased conservation (CBC) practices can be strategically positioned to achieve environmental conservation objectives as well as promote local-level socio-economic development. The KwaZulu-Natal Sandstone Sourveld (KZNSS) vegetation type is classified as endemic (to KZN, South Africa), and is at present listed as endangered. Additionally, one of the KZNSS grassland patches occurs adjacent to the low-income peri-urban community of iNanda. The study examined local community uses and perceptions of the vegetation type.Objectives: To examine the uses, perceptions and attitudes displayed by the iNanda community towards the KZNSS grassland patch. Furthermore, it is hoped that the results of this study can be utilised to inform the potential use of CBC strategies within socio-economic contexts such as iNanda.Method: A mixed methodological approach was adopted, focusing on iNanda as the case study. One hundred households were purposively interviewed. Descriptive and chi-square statistical tests were carried out to examine main data trends.Results: Respondents displayed alarming levels of unemployment (61%) and 34% relied on state grants as a source of household income. Households used the grassland for subsistence (51%), grazing (14%), recreational (13%) and cultural purposes (12%). Respondents displayed limited awareness of conservation and the ecological importance of the grassland. However, respondents recognised the need to conserve the grassland based on their perception of changes to the adjacent patch.Conclusion: Potential grassland conservation plans should consider the current use displayed by respondents. Participatory approaches to conservation such as CBC initiatives could provide much-needed socio-economic and conservation benefits.
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A survey of the fine structure of the Isovector Giant Dipole Resonance (IVGDR) was performed, using the recently commissioned Zero-degree Facility of the K600 magnetic spectrometer at iThemba LABS. ...Inelastic proton scattering at an incident energy of 200MeV was measured on
27
Al ,
40
Ca ,
56
Fe ,
58
Ni and
208
Pb . A high energy-resolution (
Δ
E
≃
40
keV FWHM) could be achieved after utilising faint-beam and dispersion-matching techniques. A considerable fine structure is observed in the energy region of the IVGDR and characteristic energy scales are extracted from the experimental data by means of a wavelet analysis. The comparison with Quasiparticle-Phonon Model (QPM) calculations provides insight into the relevance of different giant resonance decay mechanisms. Photoabsorption cross sections derived from the data assuming a dominance of relativistic Coulomb excitation are in fair agreement with previous work using real photons.
FLUKA Monte Carlo radiation transport code has been used to simulate neutron fluence spectrum at iThemba LABS neutron beam facility. Neutron beams with energy up to 200 MeV can be produced using ...different targets such as
7Li,
9Be and
12C bombarded with monoenergetic protons from the Separated-Sector Cyclotron. Simulated results at 66 MeV were compared with measured data. Different neutron emission angles with respect to the beam axis as well as the neutron background at different positions have been investigated.
Knowledge of the low-lying monopole strength in C12—the Hoyle state in particular—is crucial for our understanding of both the astrophysically important 3α reaction and of α-particle clustering. ...Multiple theoretical models have predicted a breathing mode of the Hoyle State at Ex≈9 MeV, corresponding to a radial in-phase oscillation of the underlying α clusters. The C12(α,α′)C12 and C14(p,t)C12 reactions were employed to populate states in 12C in order to search for this predicted breathing mode. A self-consistent, simultaneous analysis of the inclusive spectra with R-matrix lineshapes, together with angular distributions of charged-particle decay, yielded clear evidence for excess monopole strength at Ex≈9 MeV which is highly collective. Reproduction of the experimentally observed inclusive yields using a fit, with consistent population ratios for the various broad states, required an additional source of monopole strength. The interpretation of this additional monopole resonance as the breathing-mode excitation of the Hoyle state would provide evidence supporting a D3h symmetry for the Hoyle state itself. The excess monopole strength may complicate analysis of the properties of the Hoyle state, modifying the temperature dependence of the 3α rate at T9≳2 and ultimately, the predicted nucleosynthesis in explosive stars.
The 34Ar(α,p) 37K reaction is believed to be one of the last in a sequence of (α,p) and (p,γ) reactions within the Tz = -1 , sd-shell nuclei, known as the αp-process. This process is expected to ...influence the shape and rise times of luminosity curves coming from type I x-ray bursts (XRBs). With very little experimental information known on many of the reactions within the αp-process, stellar rates are calculated using a statistical model, such as Hauser-Feshbach. Questions on the applicability of a Hauser-Feshbach model for the 34Ar (α,p) 37K reaction arise due to level density considerations in the compound nucleus, 38Ca . We have performed high energy-resolution forward-angle 40Ca (p,t) 38Ca measurements with the K = 600 spectrograph at iThemba LABS in order to identify levels above the α-threshold in 38Ca . States identified in this work were then used to determine the 34Ar (α,p) 37K reaction rate based on a narrow-resonance formalism. Comparisons are made to two standard Hauser-Feshbach model predicted rates at XRB temperatures.
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