List of Titles

Preliminary evidence for the organisation of a bacterial community by zooplanktivores at the top of an estuarine planktonic food web

- Wasserman, Ryan J, Matcher, Gwynneth F, Vink, Tim J F, Froneman, P William

Authors: Wasserman, Ryan J , Matcher, Gwynneth F , Vink, Tim J F , Froneman, P William
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68237 , vital:29222 , https://doi.org/10.1007/s00248-014-0505-3
Description: Publisher version , As part of a larger investigation, the effect of apex predation on estuarine bacterial community structure, through trophic cascading, was investigated using experimental in situ mesocosms. Through either the removal (filtration) or addition of specific size classes of planktonic groups, four different trophic scenarios were established using estuarine water and its associated plankton. One such treatment represented a “natural” scenario in which stable apex predatory pressure was qualified. Water samples were collected over time from each of the treatments for bacterial community evaluation. These samples were assessed through pyrosequencing of the variable regions 4 and 5 of the bacterial 16S rRNA gene and analysed at the species operational taxonomic unit (OTU) level using a community procedure. The blue-green group dominated the samples, followed by Proteobacteria and Bacteroidetes. Samples were the most similar among treatments at the commencement of the experiment. While the bacterial communities sampled within each treatment changed over time, the deviation from initial appeared to be linked to the treatment trophic scenarios. The least temporal deviation-from-initial in bacterial community was found within the stable apex predatory pressure treatment. These findings are consistent with trophic cascade theory, whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity.
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Date Issued: 2015

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Pre-concentration of toxic metals using electrospun amino-functionalized nylon-6 nanofibre sorbent

- Darko, G, Sobola, A, Adewuyi, Sheriff, Okonkwo, J O, Torto, N

Authors: Darko, G , Sobola, A , Adewuyi, Sheriff , Okonkwo, J O , Torto, N
Date: 2012
Language: English
Type: Article
Identifier: vital:6571 , http://hdl.handle.net/10962/d1004134
Description: This paper presents a new approach for pre-concentrating toxic metals (As, Cd, Ni and Pb) in aqueous environments using an amino-functionalized electrospun nanofibre sorbent. The sorbent, composed of nanofibres of average diameter 80 ± 10 nm and specific surface area of 58m2 g–1, exhibited fast adsorption kinetics (<20 min) for As, Cd, Ni and Pb. The optimalpHfor the uptake of As, Cd, Ni and Pb were 5.5, 6.0, 6.5 and 11, respectively. The adsorption process best fitted the Freundlich isothermand followed the first-order kinetics. The highest pre-concentration achieved using the sorbent was 41.99 (Ni in treated wastewater). The capacity of the sorbent to pre-concentrate the toxic metals was compared with those of aqua regia and HNO3+H2O2 digestions. The pre-concentration factors achieved for Cd in river water samples can be ranked as aqua regia digestion (0.73) > adsorption (0.34)>HNO3+H2O2 (0.23) digestion.Asimilar trend was observed for Ni in river water as well as Ni andCdin tap water samples. Pb ions in the river water samples were pre-concentrated slightly better using the two digestion methods pre-concentration factors ~22) compared to adsorption method (pre-concentration factor ~21). The use of the electrospun amino-functionalized nanofibre sorbent presentsanefficientand cost-effective alternative for pre-concentration of toxic metals inaqueousenvironments.
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Date Issued: 2012

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Pomacanthus Rhomboides (Gilchrist and Thompson), the valid name for the South African Angelfish previously known as Pomacanthus Striatus

- Randall, John E, 1924-, J.L.B. Smith Institute of Ichthyology

Authors: Randall, John E, 1924- , J.L.B. Smith Institute of Ichthyology
Date: 1988-12
Subjects: Marine angelfishes -- South Africa -- Nomenclature
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/70291 , vital:29642 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 46 , The Indian Ocean angelfish from southern Africa heretofore identified as Pomacanthus striatus (Riippell, 1836) is Pomacanthus rhomboides (Gilchrist and Thompson, 1908). P. striatus is shown to be the young of P. maculosus (Forsskål, 1775) which is not known from South Africa; it occurs in the Red Sea, Persian Gulf, and along the East African coast to at least 13°S. Holacanthus coeruleus Cuvier, described from a juvenile specimen from the Red Sea, is a junior synonym of Pomacanthus asfur (Forsskål), not P. semicirculatus (Cuvier), thus casting doubt on the record of the letter from the Red Sea.
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Date Issued: 1988-12

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Pollination success in a deceptive orchid is enhanced by co-occurring rewarding magnet plants

- Johnson, Steven D, Peter, Craig I, Nilsson, L Anders, Agren, Jon

Authors: Johnson, Steven D , Peter, Craig I , Nilsson, L Anders , Agren, Jon
Date: 2003
Language: English
Type: Article
Identifier: vital:6520 , http://hdl.handle.net/10962/d1005949 , http://www.jstor.org/stable/3449962
Description: It has been debated whether pollination success in nonrewarding plants that flower in association with nectar-producing plants will be diminished by competition for pollinator visits or, alternatively, enhanced through increased local abundance of pollinators (the magnet species effect). We experimentally evaluated these effects using the nonrewarding bumblebee-pollinated orchid Anacamptis morio and associated nectar-producing plants at a site in Sweden. Pollination success (estimated as pollen receipt and pollen removal) in A. morio was significantly greater for individuals translocated to patches of nectar-producing plants (Geum rivale and Allium schoenoprasum) than for individuals placed outside (similar to20 m away) such patches. These results provide support for the existence of a facilitative magnet species effect in the interaction between certain nectar plants and A. morio. To determine the spatial scale of these interactions, we correlated the visitation rate to flowers of A. morio with the density of sympatric nectar plants in 1-m(2) and 100-m(2) plots centered around groups of translocated plants, and at the level of whole meadows (similar to0.5-2 ha). Visitation rate to flowers of A. morio was not correlated with the 1-m(2) patch density of G. rivale and A. schoenoprasum, but showed a significant positive relationship with density of these nectar plants in 100-m(2) plots. In addition, visitation to flowers of A. morio was strongly and positively related to the density of A. schoenoprasum at the level of the meadow. Choice experiments showed that bees foraging on the purple flowers of A. schoenoprasum (a particularly effective magnet species) visit the purple flowers of A. morio more readily (47.6% of choices) than bees foraging on the yellow flowers of Lotus corniculatus (17% of choices). Overall similarity in flower color and shape may increase the probability that a pollinator will temporarily shift from a nectar-producing "magnet" plant to a nonrewarding plant. We discuss the possibility of a mimicry continuum between those orchids that exploit instinctive food-seeking behavior of pollinators and those that show an adaptive resemblance to nectar-producing plants.
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Date Issued: 2003

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Physicochemical behavior of nanohybrids of mono and tetra substituted carboxyphenoxy phthalocyanine covalently linked to GSH–CdTe/CdS/ZnS quantum dots

- Oluwole, David O, Nyokong, Tebello

Authors: Oluwole, David O , Nyokong, Tebello
Date: 2015
Language: English
Type: text , Article
Identifier: vital:7266 , http://hdl.handle.net/10962/d1020275 , http://dx.doi.org/10.1016/j.poly.2014.10.024
Description: Zinc monocarboxyphenoxy and tetracarboxyphenoxy phthalocyanines were covalently linked with three different sizes of glutathione capped core/shell/shell {CdTe/CdS/ZnS(4.2), CdTe/CdS/ZnS(5.1) and CdTe/CdS/ZnS(6.7)}; a core shell {CdTe/CdS(3.1)} and core {CdTe(2.4)} quantum dots. The physicochemical behavior and Förster resonance energy transfer (FRET) processes of the nanohybrids were investigated. The highest FRET efficiency was observed with CdTe/CdS/ZnS(6.7) nanohybrids with 98% and the least efficiency was observed with CdTe(2.4) nanohybrids with 85%. The CdTe/CdS/ZnS(6.7) also showed the best physicochemical behavior. These good physicochemical properties make the synthesized nanohybrids viable photosensitizers. , Original publication is available at http://dx.doi.org/10.1016/j.poly.2014.10.024
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Date Issued: 2015

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Phylogeographic structure of Octopus vulgaris in South Africa revisited: identification of a second lineage near Durban harbour

- Teske, P R, Oosthuizen, A, Papadopoulos, I, Barker, Nigel P

Authors: Teske, P R , Oosthuizen, A , Papadopoulos, I , Barker, Nigel P
Date: 2007
Language: English
Type: text , article
Identifier: vital:6951 , http://hdl.handle.net/10962/d1013236 , http://dx.doi.org/10.1007/s00227-007-0644-x
Description: preprint , In a previous study that investigated genetic structure of Octopus vulgaris along the South African coast by sequencing the mitochondrial cytochrome oxidase III gene (COIII), all sequences generated were identical. Such a finding is unusual, because mitochondrial DNA mutates quickly, and several marine invertebrates present in southern Africa show considerable genetic variation and structure. We reanalysed the samples using two different mitochondrial markers, namely cytochrome oxidase I (COI) and the large ribosomal subunit (16S rRNA). Sequences of both these markers showed variation. The conclusion of the previous study, that South Africa’s O. vulgaris population is characterised by a lack of genetic structure along the coast, is rejected. Some specimens from Durban (southeast Africa) were genetically more different from those found in the remainder of the country than were specimens from other regions (Tristan da Cunha and Senegal). We suggest that the lineage in Durban may have been recently introduced.
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Date Issued: 2007

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Phototransferred thermoluminescence of synthetic quartz: analysis of illumination-time response curves

- Chithambo, Makaiko L, Niyonzima, P, Kalita, Jitumani M

Authors: Chithambo, Makaiko L , Niyonzima, P , Kalita, Jitumani M
Date: 2018
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/111020 , vital:33364 , https://doi.org/10.1016/j.jlumin.2018.02.029
Description: Phototransferred thermoluminescence (PTTL) induced in synthetic quartz by 470 nm blue light is reported. The glow curve measured at 5 °C/s up to 500 °C after irradiation to 100 Gy shows six peaks at 94, 116, 175, 212, 280 and 348 °C labelled I through VI and another one at 80 °C (labelled A1). PTTL is only observed for peaks A1 and I and is induced at peak A1 as long as peak III has been removed by preheating and at peak I after preheating to deplete peak VI. The inducement of PTTL even when all peaks have been removed points to deep electron traps in the quartz also acting as donors in addition to the putative ones below 500 °C. The PTTL intensity as a function of duration of illumination for A1 goes through a peak and decreases monotonically or to a stable value depending on the preheating temperature. The change of PTTL intensity as a function of illumination time is described using a set of coupled linear differential equations. The number of acceptors and donors in a particular system described in this way is influenced by the preheating temperature.
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Date Issued: 2018

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Photophysical studies of newly derivatized mono substituted phthalocyanines grafted onto silica nanoparticles via click chemistry

- Fashina, Adedayo, Amuhaya, Edith, Nyokong, Tebello

Authors: Fashina, Adedayo , Amuhaya, Edith , Nyokong, Tebello
Date: 2015
Language: English
Type: Article
Identifier: vital:7272 , http://hdl.handle.net/10962/d1020287 , Original publication is available at http://dx.doi.org/10.1016/j.saa.2014.12.070
Description: This work reports on the synthesis, characterization and photophysical studies of newly derived phthalocyanine complexes and the phthalocyanine–silica nanoparticles conjugates. The derived phthalocyanine complexes have one terminal alkyne group. The derived phthalocyanine complexes showed improved photophysical properties (ФF, ФT, ΦΔ and τT) compared to the respective phthalocyanine complexes from which they were derived. The derived phthalocyanine complexes were conjugated to the surface of an azide functionalized silica nanoparticles via copper (1) catalyzed cyclo-addition reaction. All the conjugates showed lower triplet quantum yields ranging from 0.37 to 0.44 compared to the free phthalocyanine complexes. The triplet lifetimes ranged from 352 to 484 μs for the conjugates and from 341 to 366 μs for the free phthalocyanine complexes.
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Date Issued: 2015

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Patient acceptance of HIV testing services in rural emergency departments in South Africa

- Aditi Rao, Caitlin Kennedy, Pamela Mda, Thomas C. Quinn, David Stead, Bhakti Hansoti

Authors: Aditi Rao , Caitlin Kennedy , Pamela Mda , Thomas C. Quinn , David Stead , Bhakti Hansoti
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/11260/3270 , vital:43287 , https://doi.org/10.4102/sajhivmed.v21i1.1105
Description: Background: South Africa faces the highest burden of HIV infection globally. The National Strategic Plan on HIV recommends provider-initiated HIV counselling and testing (HCT) in all healthcare facilities. However, HIV continues to overwhelm the healthcare system. Emergency department (ED)-based HCT could address unmet testing needs. Objectives: This study examines the reasons for accepting or declining HCT in South African EDs to inform the development of HCT implementation strategies. Method: We conducted a prospective observational study in two rural EDs, from June to September 2017. Patients presenting to the ED were systematically approached and offered a point-of-care test in accordance with national guidelines. Patients demographics, presenting compaint, medical history and reasons for accepting/declining testing, were recorded. A pooled analysis is presented. Results: Across sites, 2074 adult, non-critical patients in the ED were approached; 1880 were enrolled in the study. Of those enrolled, 19.7% had a previously known positive diagnosis, and 80.3% were unaware of their HIV status. Of those unaware, 90% patients accepted and 10% declined testing. The primary reasons for declining testing were ‘does not want to know status’ (37.6%), ‘in too much pain’ (34%) and ‘does not believe they are at risk’ (19.9%). Conclusions: Despite national guidelines, a high proportion of individuals remain undiagnosed, of which a majority are young men. Our study demonstrated high patient acceptance of ED-based HCT. There is a need for investment and innovation regarding effective pain management and confidential service delivery to address patient barriers. Findings support a routine, non-targeted HCT strategy in EDs. Keywords: HIV counselling and testing; South Africa; emergency department; patient acceptance; implementation research; linkage to care.
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Date Issued: 2020

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Ontogenetic and seasonal shifts in the diet of Diplodus cervinus hottentotus (Pisces: Sparidae) in southern Angola

- Winkler, Alexander C, Santos, Carmen V D, Potts, Warren M

Authors: Winkler, Alexander C , Santos, Carmen V D , Potts, Warren M
Date: 2014
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/125452 , vital:35784 , https://doi.10.2989/1814232X.2014.951392
Description: Fishes of the family Sparidae occupy a diverse range of trophic niches, from herbivores to generalist omnivores and specialist predators (Hanel and Tsigenopoulos 2011). Feeding specialisation in this family is facilitated by diversity in tooth type and anterior jaw arrangement (Vandewalle et al. 1995). Other fish families, such as Cyprinidae and Labridae, have developed crushing pharyngeal teeth to process their food. Sparids, however, have retained a simple pharyngeal tooth arrangement and instead have developed molariform teeth to process hard-shelled molluscs and invertebrate prey. Hanel and Tsigenopoulos (2011) suggested that this alternate strategy is a major factor facilitating the trophic diversity in sparid fishes.
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Date Issued: 2014

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On the correlation between annealing and variabilities in pulsed-luminescence from quartz

- Chithambo, Makaiko L

Authors: Chithambo, Makaiko L
Date: 2006
Language: English
Type: Article
Identifier: vital:6797 , http://hdl.handle.net/10962/d1003923
Description: Properties of luminescence lifetimes in quartz related to annealing between 500 and 900ºC have been investigated. The luminescence was pulse-stimulated at 470 nm from sets of granular quartz annealed at 500, 600, 700, 800, and 900ºC. The lifetimes decrease with annealing temperature from about 42 to 33 µѕ when the annealing temperature is increased from 500 to 900ºC. Luminescence lifetimes are most sensitive to duration of annealing at 600ºC, decreasing from 40.2 ± 0.7 µѕ by as much as 7 µѕ when the duration of annealing is changed from 10 to 60 min. However, at 800–900ºC lifetimes are essentially independent of annealing temperature at about 33 µѕ. Increasing the exciting beta dose causes an increase in the lifetimes of the stimulated luminescence in the sample annealed at 800ºC but not in those annealed at either 500 or 600ºC. The temperature-resolved distribution of luminescence lifetimes is affected by thermal quenching of luminescence. These features may be accounted for with reference to two principal luminescence centres involved in the luminescence emission process.
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Date Issued: 2006

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On becoming an African-Asian English academic at Rhodes University

- Naidu, Samantha

Authors: Naidu, Samantha
Date: 2004
Language: English
Type: text , article
Identifier: vital:21926 , http://hdl.handle.net/10962/14392 , https://0-www.jstor.org.wam.seals.ac.za/stable/24487641
Description: preprint , I arrived at Rhodes University English Department with not much more than a passion for literature. During the last fourteen years I have been able to observe the discipline in operation. My perspective has broadened and deepened, taking in the trajectory from Stanley Kidd and the colonial Cambridge practices, and from what might be termed the 'humanist enterprise of English studies', 1 to the white liberalism of Guy Butler in the middle of the twentieth century, then to the present post-apartheid era of humanities cutbacks and increasing commodification of knowledge.
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Date Issued: 2004

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Oceanographic environment of the Sodwana Bay coelacanths (Latimeria chalumnae), South Africa

- Roberts, M J, Ribbink, Anthony J, Morris, T

Authors: Roberts, M J , Ribbink, Anthony J , Morris, T
Date: 2006
Language: English
Type: text , Article
Identifier: vital:7156 , http://hdl.handle.net/10962/d1011883
Description: Trimix scuba divers discovered coelacanths in Jesser Canyon at a depth of 104 m on the northern KwaZulu-Natal (KZN) coast (Sodwana Bay) in October 2000. The existence of these animals at such a shallow depth and in the swift and powerful Agulhas Current led to a suggestion that this might be an isolated group swept well away from the main population in the Comoros, where they live at depths of 200–350 m with little current. Subsequent observations from three manned submersible surveys and one remotely operated vehicle expedition together with recreational diver observations indicate that the South African population of coelacanths has at least 26 individuals, mostly occupying the depth range of 104–140 m in canyons. Seventeen CTD sections collected during four cruises in 2002 and 2003 indicate the temperature range in this habitat to be similar to that found in the Comoros Islands (that is, 15–22°C cf. 15–19°C in the Comoros). However, a 2.5-month-long time series of hourly data collected by a thermistor array deployed near a known coelacanth cave in Wright Canyon indicated greater variation than anticipated, with temperature changes between 16°C and 24°C occurring in a day. Dissolved oxygen levels in this depth zone were found to range between 3.0 ml l[superscript (–1)] and 4.8 ml l[superscript (–1)] compared to 3.5 ml l[superscript (–1)] in the Comoros. The low oxygen values along this coast are a result of the shallow oxygen minimum, which becomes shallower in the southwest Indian Ocean, particularly in the Agulhas Current, than in tropical latitudes. Current velocities measured using a ship-borne ADCP in the depth range 100–140 m at Sodwana were considerably higher than those measured in the Comoros habitat (20–60 cm s[superscript (–1)] cf. 3–4 cm s[superscript (–1)]) and may be an important factor explaining the coelacanths’ occupation of the canyons found along the northern KZN shelf-break.
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Date Issued: 2006

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Oceanographic environment of the Sodwana Bay coelacanths (Latimeria chalumnae), South Africa

- Roberts, M J, Ribbink, A J, Morris, T

Authors: Roberts, M J , Ribbink, A J , Morris, T
Date: 2006
Language: English
Type: Article
Identifier: vital:7126 , http://hdl.handle.net/10962/d1010633
Description: Trimix scuba divers discovered coelacanths in Jesser Canyon at a depth of 104 m on the northern KwaZulu-Natal (KZN) coast (Sodwana Bay) in October 2000. The existence of these animals at such a shallow depth and in the swift and powerful Agulhas Current led to a suggestion that this might be an isolated group swept well away from the main population in the Comoros, where they live at depths of 200–350 m with little current. Subsequent observations from three manned submersible surveys and one remotely operated vehicle expedition together with recreational diver observations indicate that the South African population of coelacanths has at least 26 individuals, mostly occupying the depth range of 104–140 m in canyons. Seventeen CTD sections collected during four cruises in 2002 and 2003 indicate the temperature range in this habitat to be similar to that found in the Comoros Islands (that is, 15–22°C cf. 15–19°C in the Comoros). However, a 2.5-month-long time series of hourly data collected by a thermistor array deployed near a known coelacanth cave in Wright Canyon indicated greater variation than anticipated, with temperature changes between 16°C and 24°C occurring in a day. Dissolved oxygen levels in this depth zone were found to range between 3.0 ml l[superscript (–1)] and 4.8 ml l[superscript (–1)] compared to 3.5 ml l[superscript (–1)] in the Comoros. The low oxygen values along this coast are a result of the shallow oxygen minimum, which becomes shallower in the southwest Indian Ocean, particularly in the Agulhas Current, than in tropical latitudes. Current velocities measured using a ship-borne ADCP in the depth range 100–140 m at Sodwana were considerably higher than those measured in the Comoros habitat (20–60 cm s[superscript (–1)] cf. 3–4 cm s[superscript (–1)]) and may be an important factor explaining the coelacanths’ occupation of the canyons found along the northern KZN shelf-break.
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Date Issued: 2006

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Observations of the habitats and biodiversity of the submarine canyons at Sodwana Bay

- Sink, K J, Boshoff, W, Samaai, Toufiek, Timm, P G, Kerwath, S E

Authors: Sink, K J , Boshoff, W , Samaai, Toufiek , Timm, P G , Kerwath, S E
Date: 2006
Language: English
Type: Article
Identifier: vital:6771 , http://hdl.handle.net/10962/d1008065
Description: The discovery of coelacanths, Latimeria chalumnae, in Jesser Canyon off Sodwana Bay in northern KwaZulu-Natal in 2000 triggered renewed interest in the deep subtidal habitats associated with submarine canyons. Information stemming from three recreational Trimix diving expeditions in Wright and Jesser canyons between April 1998 and June 2001 revealed distinct and diverse invertebrate and fish communities in the canyons of the Greater St Lucia Wetland Park (GSLWP). In total, 69 invertebrate taxa were collected from Wright Canyon, including at least 15 new records for South Africa plus 11 potential new species and 16 range or depth extensions. Divers documented the first five coelacanth specimens and obtained information on fish distribution and abundance. Five different habitat types were recognized supporting distinct biological communities; the sandy plains outside of the canyons, scattered rock outcrops within the sandy plains, the canyon margin, canyon walls and caves and overhangs. The canyon margin is the richest habitat and supports dense communities of invertebrate suspension feeders, as well as a diverse and abundant fish fauna. Dominant canyon invertebrates included sponges, black corals, gorgonians, alcyonarian soft corals and stylasterine lace corals. These invertebrates support a diverse epifauna including basket- and brittlestars, winged oysters and other molluscs. The canyons within the GSLWP protect large populations of commercially important linefish species including the sparids, Chrysoblephus puniceus, C. anglicus, Polysteganus praeorbitalis and P. caeruleopunctatus, as well as several species of serranids and lutjanids. Additional biological sampling and standardized quantitative sampling within the canyons and deep reefs is required to develop a better understanding of their biological communities and the factors that shape them.
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Date Issued: 2006

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Nuruddin Farah: variations on the theme of return

- Naicker, Kamil

Authors: Naicker, Kamil
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/149643 , vital:38871 , https://www.ajol.info/index.php/tvl/article/view/196356
Description: This article explores the role of the returnee protagonist in selected works of Nuruddin Farah. Nadine Gordimer described Farah as “one of the real interpreters” of Africa and this article argues that Farah’s returnees operate as interpreters themselves, their liminality working to mediate between international readers and “local” subject matter. However, it also observes that Farah, who spent decades in exile, is often as preoccupied with writing non-belonging as he is with rendering Somalia itself. Farah’s returnee narratives are, broadly, novels of redress, in which characters enact their return in an attempt to seek out the missing, rebuild the lost or reclaim the stolen, with imperfect results. In exploring these variations on homecoming, the paper investigates the ways in which Farah’s body of work reflects shifts in identity politics over time, and the unique pressures these shifts exert on the homecoming arc.
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Date Issued: 2020

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Nonlinear optical response of tetra and mono substituted zinc phthalocyanine complexes

- Fashina, Adedayo, Nyokong, Tebello

Authors: Fashina, Adedayo , Nyokong, Tebello
Date: 2015
Language: English
Type: Article
Identifier: vital:7281 , http://hdl.handle.net/10962/d1020318 , Original publication is available at http://dx.doi.org/10.1016/j.jlumin.2015.06.003
Description: The nonlinear absorption properties of 6 mono-substituted and 3 symmetric zinc phthalocyanine complexes have been studied in dimethylsulfoxide (DMSO) using 10 ns pulses at 532 nm. The non linear absorption of the complexes has been studied using the Z-scan technique. The study showed that both the singlet and triplet excited states contribute to the non linear absorption behavior. The nonlinear third-order susceptibility and second-order hyperpolarizability values of the complexes are reported. It was observed that two of the symmetric phthalocyanine complexes (5-α substituted with aminophenoxy and 9-β substituted with carboxyphenoxy) showed better and promising optical nonlinearity when compared to the other complexes studied.
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Date Issued: 2015

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Non-material costs of wildlife conservation to local people and their implications for conservation interventions:

- Thondhlana, Gladman, Redpath, Stephen Mark, Vedeld, Pål Olav, van Eden, Lily, Pascual, Unai, Sherren, Kate, Murata, Chenai

Authors: Thondhlana, Gladman , Redpath, Stephen Mark , Vedeld, Pål Olav , van Eden, Lily , Pascual, Unai , Sherren, Kate , Murata, Chenai
Date: 2020
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/150174 , vital:38946 , https://doi.org/10.1016/j.biocon.2020.108578
Description: In assessment of costs (and benefits) of wildlife conservation, conventional economic valuation frameworks may inadequately address various non-tangible values and neglect social, cultural and political contexts of resources and their use. Correspondingly, there seems to be much more focus on quantifying the economic, material benefits and costs of wildlife conservation than the non-material aspects that also affect human well-being. In addition, current research on the costs of wildlife conservation tends to be discipline-focused which constrains comparability, often causing conceptual ambiguity. This paper is an attempt to address this ambiguity. While there is growing acknowledgement of the material costs of wildlife conservation, we contend that employing a broader, composite social well-being approach may provide better conceptual insights on—and practical options for—managing various non-material impacts of wildlife conservation for local people.
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Date Issued: 2020

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