https://commons.ru.ac.za/vital/access/manager/Index en-us 5 https://commons.ru.ac.za/vital/access/manager/Repository/vital:8313 Wed 12 May 2021 23:22:29 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:931 Wed 12 May 2021 23:08:04 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10243 Wed 12 May 2021 22:52:17 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1407 Wed 12 May 2021 22:43:54 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11205 Wed 12 May 2021 22:43:06 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11369 Wed 12 May 2021 22:37:07 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4286 Wed 12 May 2021 22:28:40 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10557 Wed 12 May 2021 22:24:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8889 Wed 12 May 2021 22:21:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3665 Wed 12 May 2021 20:37:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10665 Wed 12 May 2021 20:35:59 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4557 Wed 12 May 2021 20:17:39 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10596 Wed 12 May 2021 20:13:21 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10062 Wed 12 May 2021 20:12:28 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10356 Wed 12 May 2021 20:06:24 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11197 Wed 12 May 2021 20:04:28 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:29734 Wed 12 May 2021 20:03:38 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:26537 Wed 12 May 2021 20:02:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9827 Wed 12 May 2021 19:51:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5609 Wed 12 May 2021 19:43:43 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8888 Wed 12 May 2021 19:41:45 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11661 Wed 12 May 2021 19:40:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2447 Wed 12 May 2021 19:37:40 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9331 Wed 12 May 2021 19:22:01 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10727 Wed 12 May 2021 19:20:42 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9463 Wed 12 May 2021 19:20:18 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11660 Wed 12 May 2021 19:19:12 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5610 Wed 12 May 2021 18:41:58 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9233 Wed 12 May 2021 18:33:36 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4741 Wed 12 May 2021 18:16:27 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5621 Wed 12 May 2021 18:05:21 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9829 Wed 12 May 2021 18:04:32 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10510 Wed 12 May 2021 17:48:52 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10354 Wed 12 May 2021 17:32:11 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3888 Wed 12 May 2021 17:29:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4562 Co(II) > Ni(II). The Schiff-base derivatives were prepared from the ligands and para-methoxysalicylaldehyde and their Cu(II) complexes were synthesized in order to determine their biological activity. The Schiff-base ligands were found to be less active than their parent ligands. The Cu(II) complexes are not soluble in water, DMSO or DMF, as a result and could not be evaluated for their biological activity. Based on the good results from the antimicrobial evaluation, the antiplasmodial activity of some of the Co(II), Ni(II) and Cu(II) complexes of the thiomethylated ligands against Plasmodium falciparum (FCR-3) was determined. At 50 μM concentration level, the Cu(II) complexes show activity equal or better than the prophylactic chloroquine. The Cu(II) complexes with the methoxy-substituted demonstrated exceptional activity but their Co(II) and Ni(II) analogues did not show any activity. The cytotoxicity of the active Cu(II) complexes at 50 μM concentration was determined against the breast cancer cell line (MDA-MB-231). The compounds destroyed the cancer cell in the range of 28–40%, thus showing their preferred activity against the parasitic cell instead of the cancer cell. The selectivity demonstrated by these compounds have shown them to be potential antimalarial agents and this could be further investigated.]]> Wed 12 May 2021 17:24:20 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3337 Wed 12 May 2021 17:08:03 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10021 Wed 12 May 2021 17:05:50 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11589 Wed 12 May 2021 16:43:40 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11444 Wed 12 May 2021 16:42:36 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9025 Wed 12 May 2021 16:42:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:26553 Wed 12 May 2021 16:39:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4281 Ni²⁺ > Zn²⁺ > Cd²⁺> Co²⁺ was achieved as a function of pH. At pH 1.65 the extracted copper, from a synthetic mixture of the base metals reached 90.13(±0.90)%, and through a two-step extraction process 98.22(±0.29)% copper was recovered with negligible nickel and cobalt impurities. Stripping of the copper from the loaded organic phase using TraceSelect sulphuric acid at pH 0.35 yielded 96.60(±0.44)% of the loaded quantity after the second stage of stripping. The separation of Ni²⁺ from the borderline and hard acids; Co²⁺, Cu²⁺, Zn²⁺, Fe2²⁺, Fe²⁺, Mn²⁺, Mg2²⁺ and Ca²⁺ at a pH range of 0.5-3.5 with OPIM and DNNSA was acvieved to the tune of a ΔpH½≈ 1.6 with respect to cobalt from a sulfate and sulfate/chloride media. A three-stage counter-current extraction of Ni²⁺, at the optimized pH of 1.89, from a synthetic mixture of Ni²⁺, Co²⁺ and Cu²⁺, yielded 99.01(±1.79)%. The total co-extracted Cu²⁺ was 48.72(±0.24)% of the original quantity in the mixture, and it was 19.85(±0.28%) for Co²⁺. The co-extracted Cu²⁺ was scrubbed off from the loaded organic phase at pH≈8.5 by using an ammonium buffer, while co-extracted Co²⁺ was selectively and quantitatively stripped with H₂SO₄ at pH 1.64. The total recovery of Ni²⁺ by stripping at pH 0.32 was 94.05(±1.70)%. In the solid-liquid system, Ni²⁺ was separated from Co²⁺, Cu²⁺, and Fe²⁺ with the microspherical resins funtionalised with 2,2′-pyridylimidazole by a separation factor (β) in the range 22-45. Electrospun nanofibers as sorbents yielded high sorption capacity in the range of 0.97 - 1.45 mmol.g⁻¹ for the same metals ions. Thus, 1-octylimidazole-2-aldoxime (OIMOX), and1-octyl-2-(2′-pyridyl)imidazole (OPIM) can be effectively utilized alongside DNNSA as a co-extractant in the separation of Cu²⁺ and Ni²⁺ respectively from base metals in acidic sulfate medium in a solvent extraction process, and the latter as a selective ligand in the solid-liquid separation of Ni²⁺ from Co²⁺, Cu²⁺, and Fe²⁺.]]> Wed 12 May 2021 16:26:16 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5397 Wed 12 May 2021 16:16:19 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:20493 Wed 12 May 2021 16:16:01 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9815 Wed 12 May 2021 16:12:17 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6023 Wed 12 May 2021 15:59:29 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6052 Wed 12 May 2021 15:55:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11690 Wed 12 May 2021 15:51:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9583 Wed 12 May 2021 15:49:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9635 Wed 12 May 2021 15:47:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11195 Wed 12 May 2021 15:45:10 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4439 Wed 12 May 2021 15:44:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1891 Wed 12 May 2021 15:44:06 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:40373 Wed 12 May 2021 14:52:10 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3411 Thu 13 May 2021 13:55:25 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11140 Thu 13 May 2021 08:14:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9280 Thu 13 May 2021 08:14:15 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9137 Thu 13 May 2021 08:07:05 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11703 Thu 13 May 2021 07:37:49 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:21137 Thu 13 May 2021 07:18:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4278 Thu 13 May 2021 07:14:17 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9584 Thu 13 May 2021 07:08:26 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10672 Thu 13 May 2021 07:02:31 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:18456 Thu 13 May 2021 06:46:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5198 Thu 13 May 2021 06:45:57 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11582 0.05), woody species diversity as well as compositional percentage for D.eriatha, C.plurinodis, S.fimbriatus, A.karro and E.rigida. Burning increased decreasers and increaser II species proportions and reduced (P ≤ 0.05) grass yield, total canopy volume, tree height, canopy height main stem diameter and sprouts diameter. Long-term burning, grazing, and goats browsing had differential effects on site stability. The effects on basal cover, tuft to tuft distance, tufts diameter, canopy distance and basal distance as a consequence of long-term burning, grazing, and goats browsing were not significantly different, whereas the effects on standing dead grass biomass as a result of long-term burning frequencies were significantly different. Long-term effects of burning followed by ten-year period of fire exclusion had significantly different effects on tuft-tuft distance but did not have statistically different effects on tufts diameter, canopy distance and basal distance. Long-term burning grazing and browsing had significantly different effects on attributes of hydrologic functions and nutrient cycling in the rangeland ecosystem (grass litter biomass, SOC and BMC). Long-term effects of burning followed by ten-year period of fire exclusion had significantly different effects on grass litter biomass, and SOC. Through their effect on vegetation and organic matter characteristics, burning, grazing and browsing could influence functionality of selected rangeland ecological processes such as biological community integrity, productivity and plant vigour, site stability, hydrologic function and nutrient cycling.]]> Thu 13 May 2021 06:34:05 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2517 Thu 13 May 2021 06:20:31 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4729 Thu 13 May 2021 05:45:42 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5587 Thu 13 May 2021 05:39:45 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2752 Thu 13 May 2021 05:33:47 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4555 Thu 13 May 2021 05:23:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5504 Thu 13 May 2021 05:20:46 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4060 Thu 13 May 2021 05:15:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1314 Thu 13 May 2021 04:59:12 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8437 Thu 13 May 2021 04:54:24 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:16192 Thu 13 May 2021 04:52:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10004 Thu 13 May 2021 04:45:50 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3555 Thu 13 May 2021 04:42:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9826 Thu 13 May 2021 04:41:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11307 Thu 13 May 2021 04:15:58 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10555 Thu 13 May 2021 03:51:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:16194 Thu 13 May 2021 03:32:28 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5588 Thu 13 May 2021 03:05:37 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8338 Thu 13 May 2021 02:34:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8245 Thu 13 May 2021 02:17:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8857 Thu 13 May 2021 02:11:39 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8775 Thu 13 May 2021 01:59:48 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1033 Thu 13 May 2021 01:50:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3508 Thu 13 May 2021 01:44:54 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5396 Thu 13 May 2021 01:11:32 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10655 2 km) and Congo (>200 m) are linked to interactions between the lithosphere and mantle geodynamics, and how these processes likely affected global climate changes.]]> Thu 13 May 2021 00:52:18 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6024 Thu 13 May 2021 00:27:55 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4282 Thu 13 May 2021 00:27:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:9023 Thu 13 May 2021 00:22:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11597 Thu 13 May 2021 00:16:02 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2736 Thu 13 May 2021 00:12:18 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1836 Thu 06 Jul 2023 12:06:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2531 Mon 10 Oct 2022 14:29:46 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2530 Mon 10 Oct 2022 14:29:19 SAST ]]>