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Implementation of access and benefit-sharing measures has consequences for classical biological control of weeds:
- Silvestri, Luciano, Sosa, Alejandro, Mc Kay, Fernando, Vitorino, Marcelo Diniz, Hill, Martin, Zachariades, Costas, Hight, Stephen, Weyl, Philip, Smith, David, Djeddour, Djamila, Mason, Peter G
- Authors: Silvestri, Luciano , Sosa, Alejandro , Mc Kay, Fernando , Vitorino, Marcelo Diniz , Hill, Martin , Zachariades, Costas , Hight, Stephen , Weyl, Philip , Smith, David , Djeddour, Djamila , Mason, Peter G
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150285 , vital:38964 , https://link.springer.com/article/10.1007/s10526-019-09988-4
- Description: The Convention on Biological Diversity and the Nagoya Protocol establish that genetic resources shall be accessed only upon the existence of prior informed consent of the country that provides those resources and that benefits arising from their utilization shall be shared. Pursuant to both agreements several countries have adopted regulations on access and benefit-sharing. These regulations have created a challenging obstacle to classical biological control of weeds. This paper reviews the experiences of Argentina, Brazil, South Africa, the USA, Canada and CABI in implementing access and benefit-sharing regulations and the implications these measures have on the effective and efficient access, exchange and utilization of biological control agents.
- Full Text:
- Authors: Silvestri, Luciano , Sosa, Alejandro , Mc Kay, Fernando , Vitorino, Marcelo Diniz , Hill, Martin , Zachariades, Costas , Hight, Stephen , Weyl, Philip , Smith, David , Djeddour, Djamila , Mason, Peter G
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150285 , vital:38964 , https://link.springer.com/article/10.1007/s10526-019-09988-4
- Description: The Convention on Biological Diversity and the Nagoya Protocol establish that genetic resources shall be accessed only upon the existence of prior informed consent of the country that provides those resources and that benefits arising from their utilization shall be shared. Pursuant to both agreements several countries have adopted regulations on access and benefit-sharing. These regulations have created a challenging obstacle to classical biological control of weeds. This paper reviews the experiences of Argentina, Brazil, South Africa, the USA, Canada and CABI in implementing access and benefit-sharing regulations and the implications these measures have on the effective and efficient access, exchange and utilization of biological control agents.
- Full Text:
Implementing prolonged exposure therapy for PTSD in a context of ongoing adversity: a clinical case study
- Booysen, Duane D, Kagee, Ashraf
- Authors: Booysen, Duane D , Kagee, Ashraf
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149275 , vital:38821 , https://0-doi.org.wam.seals.ac.za/10.1177/1534650120925918
- Description: Obstacles regarding the implementation of empirically supported treatments (ESTs) for mental disorders such as post-traumatic stress disorder (PTSD) still require further investigation. One notable obstacle is whether persons in low- and middle-income countries (LMICs) residing in a context of ongoing adversity would benefit from an EST for PTSD. We reflect on the utility of a brief prolonged exposure intervention at a primary care community-counseling center in South Africa. “Sam,” a 45-year-old, female was assessed at baseline, during treatment, postassessment, and at 3-month follow-up. At the beginning of treatment, Sam had a positive diagnosis for PTSD (PSSI-5 = 55, and cutoff is 23) and at the end of treatment (PSSI-5 = 17), and 3-month follow-up (PSSI-5 = 21), she had a negative diagnosis for PTSD. We reflect on the mediating effects that contextual factors such as gang violence had on the treatment process and the feasibility of implementing ESTs for PTSD in LMICs under conditions of ongoing adversity.
- Full Text:
- Authors: Booysen, Duane D , Kagee, Ashraf
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149275 , vital:38821 , https://0-doi.org.wam.seals.ac.za/10.1177/1534650120925918
- Description: Obstacles regarding the implementation of empirically supported treatments (ESTs) for mental disorders such as post-traumatic stress disorder (PTSD) still require further investigation. One notable obstacle is whether persons in low- and middle-income countries (LMICs) residing in a context of ongoing adversity would benefit from an EST for PTSD. We reflect on the utility of a brief prolonged exposure intervention at a primary care community-counseling center in South Africa. “Sam,” a 45-year-old, female was assessed at baseline, during treatment, postassessment, and at 3-month follow-up. At the beginning of treatment, Sam had a positive diagnosis for PTSD (PSSI-5 = 55, and cutoff is 23) and at the end of treatment (PSSI-5 = 17), and 3-month follow-up (PSSI-5 = 21), she had a negative diagnosis for PTSD. We reflect on the mediating effects that contextual factors such as gang violence had on the treatment process and the feasibility of implementing ESTs for PTSD in LMICs under conditions of ongoing adversity.
- Full Text:
In Vitro Release Testing (IVRT) of Topical Hydrocortisone Acetate Creams: a novel approach using positive and negative controls
- Mudyahoto, Nyengeterai Amanda, Rath, Seeprarani, Ramanah, Ashmita, Kanfer, Isadore
- Authors: Mudyahoto, Nyengeterai Amanda , Rath, Seeprarani , Ramanah, Ashmita , Kanfer, Isadore
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149849 , vital:38888 , dx.doi.org/10.14227/DT270120P6
- Description: The objective was to develop and validate an in vitro release testing (IVRT) method to assess the release of hydrocortisone acetate (HCA) from five topical formulations. A marketed generic cream containing 1% HCA was used as the reference product. Vertical diffusion cells (VDCs) were used to assess and compare the release rates of HCA from cream formulations containing 0.5%, 1%, and 1.5% HCA. The study describes a novel approach to test the discriminatory power by including both positive and negative controls to declare pharmaceutical equivalence or inequivalence. The validated method was found to be sensitive, linear, precise, reproducible, robust, and selective for the analysis of HCA from topical cream products. Equivalence or inequivalence was established based on SUPAC-SS acceptance criteria using a 90% CI with limits of 75–133.33%. The IVRT method was shown to have discriminatory ability to appropriately measure significant differences in drug release from various cream formulations. This approach also provides useful information for the future development of acceptable IVRT methods to assess topical dosage forms for local action containing different drugs.
- Full Text:
- Authors: Mudyahoto, Nyengeterai Amanda , Rath, Seeprarani , Ramanah, Ashmita , Kanfer, Isadore
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149849 , vital:38888 , dx.doi.org/10.14227/DT270120P6
- Description: The objective was to develop and validate an in vitro release testing (IVRT) method to assess the release of hydrocortisone acetate (HCA) from five topical formulations. A marketed generic cream containing 1% HCA was used as the reference product. Vertical diffusion cells (VDCs) were used to assess and compare the release rates of HCA from cream formulations containing 0.5%, 1%, and 1.5% HCA. The study describes a novel approach to test the discriminatory power by including both positive and negative controls to declare pharmaceutical equivalence or inequivalence. The validated method was found to be sensitive, linear, precise, reproducible, robust, and selective for the analysis of HCA from topical cream products. Equivalence or inequivalence was established based on SUPAC-SS acceptance criteria using a 90% CI with limits of 75–133.33%. The IVRT method was shown to have discriminatory ability to appropriately measure significant differences in drug release from various cream formulations. This approach also provides useful information for the future development of acceptable IVRT methods to assess topical dosage forms for local action containing different drugs.
- Full Text:
Increasing temperatures increase the risk of reproductive failure in a near threatened alpine groundnesting bird, the Cape Rockjumper Chaetops frenatus:
- Oswald, Krista N, Diener, Elizabeth F, Diener, John P, Cunningham, Susan J, Smit, Ben, Lee, Alan T K
- Authors: Oswald, Krista N , Diener, Elizabeth F , Diener, John P , Cunningham, Susan J , Smit, Ben , Lee, Alan T K
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149324 , vital:38825 , https://0-doi.org.wam.seals.ac.za/10.1111/ibi.12846
- Description: A major cause of reproductive failure in birds is nest predation. Predation risk depends on predator type, as predators vary in their ecology and sensory modalities (e.g. visual vs. olfactory). Snakes (generally olfactory predators) are a major nest predator for small birds, with predation strongly associated with higher temperatures. We investigated nest survival in a ground‐nesting alpine species, the Cape Rockjumper Chaetops frenatus , endemic to alpine fynbos in southwestern South Africa. We collected 3 years of nest data, testing whether nest survival was related to (1) habitat stage (early post‐fire vs. late post‐fire habitat, ≤ 3 and > 3 years since fire respectively), (2) nest concealment and (3) temperature. We found that nests had better survival at lower temperatures, with snake predation (our main source of predation) increasing in higher temperatures.
- Full Text:
- Authors: Oswald, Krista N , Diener, Elizabeth F , Diener, John P , Cunningham, Susan J , Smit, Ben , Lee, Alan T K
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149324 , vital:38825 , https://0-doi.org.wam.seals.ac.za/10.1111/ibi.12846
- Description: A major cause of reproductive failure in birds is nest predation. Predation risk depends on predator type, as predators vary in their ecology and sensory modalities (e.g. visual vs. olfactory). Snakes (generally olfactory predators) are a major nest predator for small birds, with predation strongly associated with higher temperatures. We investigated nest survival in a ground‐nesting alpine species, the Cape Rockjumper Chaetops frenatus , endemic to alpine fynbos in southwestern South Africa. We collected 3 years of nest data, testing whether nest survival was related to (1) habitat stage (early post‐fire vs. late post‐fire habitat, ≤ 3 and > 3 years since fire respectively), (2) nest concealment and (3) temperature. We found that nests had better survival at lower temperatures, with snake predation (our main source of predation) increasing in higher temperatures.
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Influence of intra-and interspecific variation in predator–prey body size ratios on trophic interaction strengths:
- Cuthbert, Ross N, Wasserman, Ryan J, Dalu, Tatenda, Kaiser, Horst, Weyl, Olaf L F, Dick, Jaimie T A, Sentis, Arnaud, McCoy, Michael W, Alexander, Mhairi E
- Authors: Cuthbert, Ross N , Wasserman, Ryan J , Dalu, Tatenda , Kaiser, Horst , Weyl, Olaf L F , Dick, Jaimie T A , Sentis, Arnaud , McCoy, Michael W , Alexander, Mhairi E
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149358 , vital:38839 , https://0-doi.org.wam.seals.ac.za/10.1002/ece3.6332
- Description: Predation is a pervasive force that structures food webs and directly influences ecosystem functioning. The relative body sizes of predators and prey may be an important determinant of interaction strengths. However, studies quantifying the combined influence of intra‐ and interspecific variation in predator–prey body size ratios are lacking. We use a comparative functional response approach to examine interaction strengths between three size classes of invasive bluegill and largemouth bass toward three scaled size classes of their tilapia prey. We then quantify the influence of intra‐ and interspecific predator–prey body mass ratios on the scaling of attack rates and handling times.
- Full Text:
- Authors: Cuthbert, Ross N , Wasserman, Ryan J , Dalu, Tatenda , Kaiser, Horst , Weyl, Olaf L F , Dick, Jaimie T A , Sentis, Arnaud , McCoy, Michael W , Alexander, Mhairi E
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149358 , vital:38839 , https://0-doi.org.wam.seals.ac.za/10.1002/ece3.6332
- Description: Predation is a pervasive force that structures food webs and directly influences ecosystem functioning. The relative body sizes of predators and prey may be an important determinant of interaction strengths. However, studies quantifying the combined influence of intra‐ and interspecific variation in predator–prey body size ratios are lacking. We use a comparative functional response approach to examine interaction strengths between three size classes of invasive bluegill and largemouth bass toward three scaled size classes of their tilapia prey. We then quantify the influence of intra‐ and interspecific predator–prey body mass ratios on the scaling of attack rates and handling times.
- Full Text:
Integrated landscape change analysis of protected areas and their surrounding landscapes: application in the Brazilian Cerrado
- Bellón, Beatriz, Blanco, Julien, De Vos, Alta, De Oliviera Roque, Fabio, Pays, Olivier, Renaud, Pierre-Cyril
- Authors: Bellón, Beatriz , Blanco, Julien , De Vos, Alta , De Oliviera Roque, Fabio , Pays, Olivier , Renaud, Pierre-Cyril
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148681 , vital:38763 , https://doi.org/10.3390/rs12091413
- Description: Remote sensing tools have been long used to monitor landscape dynamics inside and around protected areas. Hereto, scientists have largely relied on land use and land cover (LULC) data to derive indicators for monitoring these dynamics, but these metrics do not capture changes in the state of vegetation surfaces that may compromise the ecological integrity of conservation areas’ landscapes. Here, we introduce a methodology that combines LULC change estimates with three Normalized Difference Vegetation Index-based proxy indicators of vegetation productivity, phenology, and structural change. We illustrate the utility of this methodology through a regional and local analysis of the landscape dynamics in the Cerrado Biome in Brazil in 2001 and 2016. Despite relatively little natural vegetation loss inside core protected areas and their legal buffer zones, the different indicators revealed significant LULC conversions from natural vegetation to farming land, general productivity loss, homogenization of natural forests, significant agricultural expansion, and a general increase in productivity. These results suggest an overall degradation of habitats and intensification of land use in the studied conservation area network, highlighting serious conservation inefficiencies in this region and stressing the importance of integrated landscape change analyses to provide complementary indicators of ecologically-relevant dynamics in these key conservation areas.
- Full Text:
- Authors: Bellón, Beatriz , Blanco, Julien , De Vos, Alta , De Oliviera Roque, Fabio , Pays, Olivier , Renaud, Pierre-Cyril
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148681 , vital:38763 , https://doi.org/10.3390/rs12091413
- Description: Remote sensing tools have been long used to monitor landscape dynamics inside and around protected areas. Hereto, scientists have largely relied on land use and land cover (LULC) data to derive indicators for monitoring these dynamics, but these metrics do not capture changes in the state of vegetation surfaces that may compromise the ecological integrity of conservation areas’ landscapes. Here, we introduce a methodology that combines LULC change estimates with three Normalized Difference Vegetation Index-based proxy indicators of vegetation productivity, phenology, and structural change. We illustrate the utility of this methodology through a regional and local analysis of the landscape dynamics in the Cerrado Biome in Brazil in 2001 and 2016. Despite relatively little natural vegetation loss inside core protected areas and their legal buffer zones, the different indicators revealed significant LULC conversions from natural vegetation to farming land, general productivity loss, homogenization of natural forests, significant agricultural expansion, and a general increase in productivity. These results suggest an overall degradation of habitats and intensification of land use in the studied conservation area network, highlighting serious conservation inefficiencies in this region and stressing the importance of integrated landscape change analyses to provide complementary indicators of ecologically-relevant dynamics in these key conservation areas.
- Full Text:
Lions do not change rivers: complex African savannas preclude top-down forcing by large carnivores
- Comley, Jessica, Joubert, Christoffel J, Mgqatsa, Nokubonga, Parker, Dan M
- Authors: Comley, Jessica , Joubert, Christoffel J , Mgqatsa, Nokubonga , Parker, Dan M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149215 , vital:38816 , https://doi.org/10.1016/j.jnc.2020.125844
- Description: Trophic cascade theories such as the ‘behaviourally-mediated trophic cascade hypothesis’ (BMTCH), have mainstreamed as ecological tools for conserving biodiversity and restoring ecosystems. The BMTCH relies on indirect negative effects of large carnivores through suppression of mesocarnivore activity and habitat use. Importantly, effects of top carnivores on mesocarnivores varies over time and space, is dependent on the species involved, and local context. In South Africa, there are very few free-ranging carnivores, as populations are often restricted to enclosed reserves. While predator-proof fences reduce human-wildlife conflict, they also influence space use within communities. We used an enclosed reserve with a relatively full complement of carnivores to test the generality of the BMTCH in the African context. Using single-species, multi-season occupancy models we investigated the spatial dynamics of multiple carnivores. We also investigated spatial partitioning by vegetation type and temporal partitioning.
- Full Text:
- Authors: Comley, Jessica , Joubert, Christoffel J , Mgqatsa, Nokubonga , Parker, Dan M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149215 , vital:38816 , https://doi.org/10.1016/j.jnc.2020.125844
- Description: Trophic cascade theories such as the ‘behaviourally-mediated trophic cascade hypothesis’ (BMTCH), have mainstreamed as ecological tools for conserving biodiversity and restoring ecosystems. The BMTCH relies on indirect negative effects of large carnivores through suppression of mesocarnivore activity and habitat use. Importantly, effects of top carnivores on mesocarnivores varies over time and space, is dependent on the species involved, and local context. In South Africa, there are very few free-ranging carnivores, as populations are often restricted to enclosed reserves. While predator-proof fences reduce human-wildlife conflict, they also influence space use within communities. We used an enclosed reserve with a relatively full complement of carnivores to test the generality of the BMTCH in the African context. Using single-species, multi-season occupancy models we investigated the spatial dynamics of multiple carnivores. We also investigated spatial partitioning by vegetation type and temporal partitioning.
- Full Text:
Low-frequency observations of the giant radio galaxy NGC 6251:
- Cantwell, T M, Bray, J D, Croston, J H, Scaife, A M M, Mulcahy, D D, Best, P N, Brüggen, M, Brunetti, G, Callingham, J R, Clarke, A O, Hardcastle, M J, Harwood, J J, Heald, G, Heesen, V, Iacobelli, M, Jamrozy, M, Morganti, R, Orru, E, O’Sullivan, S P, Riseley, C J, Röttgering, H J A, Shulevski, A, Sridhar, S S, Tasse, C, Van Eck, C L
- Authors: Cantwell, T M , Bray, J D , Croston, J H , Scaife, A M M , Mulcahy, D D , Best, P N , Brüggen, M , Brunetti, G , Callingham, J R , Clarke, A O , Hardcastle, M J , Harwood, J J , Heald, G , Heesen, V , Iacobelli, M , Jamrozy, M , Morganti, R , Orru, E , O’Sullivan, S P , Riseley, C J , Röttgering, H J A , Shulevski, A , Sridhar, S S , Tasse, C , Van Eck, C L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149931 , vital:38913 , https://0-doi.org.wam.seals.ac.za/10.1093/mnras/staa1160
- Description: We present LOFAR observations at 150 MHz of the borderline FRI/FRII giant radio galaxy NGC 6251. This paper presents the most sensitive and highest resolution images of NGC 6251 at these frequencies to date, revealing for the first time a low-surface-brightness extension to the northern lobe, and a possible backflow associated with the southern lobe. The integrated spectra of components of NGC 6251 are consistent with previous measurements at higher frequencies, similar to results from other LOFAR studies of nearby radio galaxies.
- Full Text:
- Authors: Cantwell, T M , Bray, J D , Croston, J H , Scaife, A M M , Mulcahy, D D , Best, P N , Brüggen, M , Brunetti, G , Callingham, J R , Clarke, A O , Hardcastle, M J , Harwood, J J , Heald, G , Heesen, V , Iacobelli, M , Jamrozy, M , Morganti, R , Orru, E , O’Sullivan, S P , Riseley, C J , Röttgering, H J A , Shulevski, A , Sridhar, S S , Tasse, C , Van Eck, C L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149931 , vital:38913 , https://0-doi.org.wam.seals.ac.za/10.1093/mnras/staa1160
- Description: We present LOFAR observations at 150 MHz of the borderline FRI/FRII giant radio galaxy NGC 6251. This paper presents the most sensitive and highest resolution images of NGC 6251 at these frequencies to date, revealing for the first time a low-surface-brightness extension to the northern lobe, and a possible backflow associated with the southern lobe. The integrated spectra of components of NGC 6251 are consistent with previous measurements at higher frequencies, similar to results from other LOFAR studies of nearby radio galaxies.
- Full Text:
Mapping subtidal estuarine habitats with a remotely operated underwater vehicle (ROV):
- Wasserman, J, Claassens, L, Adams, J B
- Authors: Wasserman, J , Claassens, L , Adams, J B
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150163 , vital:38945 , DOI: 10.2989/1814232X.2020.1731598
- Description: Subtidal habitats have not yet been accounted for in habitat maps of South African estuaries. In this study, a novel method for mapping subtidal estuarine habitats, using a remotely operated underwater vehicle (ROV) piloted from a boat, was developed and tested in the Knysna Estuary. Video footage was recorded along 48 transects across the width of the estuary, and then reviewed to identify, classify and map habitats. Using the method developed in this study, 21 hours of footage was recorded over 15 days of sampling, and about 30 hours of post-processing was carried out to map an area exceeding 850 ha. This study has produced the first baseline dataset of subtidal habitats for a South African estuary. Additionally, the study revealed the previously unknown distribution of the invasive red seaweed Asparagopsis taxiformis, and the underestimation in previous studies of the estuary of area cover of eelgrass Zostera capensis by 130 ha.
- Full Text:
- Authors: Wasserman, J , Claassens, L , Adams, J B
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150163 , vital:38945 , DOI: 10.2989/1814232X.2020.1731598
- Description: Subtidal habitats have not yet been accounted for in habitat maps of South African estuaries. In this study, a novel method for mapping subtidal estuarine habitats, using a remotely operated underwater vehicle (ROV) piloted from a boat, was developed and tested in the Knysna Estuary. Video footage was recorded along 48 transects across the width of the estuary, and then reviewed to identify, classify and map habitats. Using the method developed in this study, 21 hours of footage was recorded over 15 days of sampling, and about 30 hours of post-processing was carried out to map an area exceeding 850 ha. This study has produced the first baseline dataset of subtidal habitats for a South African estuary. Additionally, the study revealed the previously unknown distribution of the invasive red seaweed Asparagopsis taxiformis, and the underestimation in previous studies of the estuary of area cover of eelgrass Zostera capensis by 130 ha.
- Full Text:
Maximal-entropy initial state of the Universe as a microscopic description of inflation:
- Brustein, Ram, Medved, A J M
- Authors: Brustein, Ram , Medved, A J M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149682 , vital:38874 , https://0-doi.org.wam.seals.ac.za/10.1103/PhysRevD.101.123502
- Description: We propose that the initial state of the Universe was an isotropic state of maximal entropy. Such a state can be described in terms of a state of closed, interacting, fundamental strings in their high-temperature Hagedorn phase, which constitutes a novel microscopic model for the state of the Universe when it is at the highest sustainable temperature. This state resolves the big-bang singularity by replacing the past of the hot big-bang Universe and sets inflationary initial conditions for the subsequent evolution of the thermal radiation and the semiclassical cosmological geometry. The entropy density in this state is equal to the square root of the energy density in Planck units, while the pressure is positive and equal to the energy density.
- Full Text:
- Authors: Brustein, Ram , Medved, A J M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149682 , vital:38874 , https://0-doi.org.wam.seals.ac.za/10.1103/PhysRevD.101.123502
- Description: We propose that the initial state of the Universe was an isotropic state of maximal entropy. Such a state can be described in terms of a state of closed, interacting, fundamental strings in their high-temperature Hagedorn phase, which constitutes a novel microscopic model for the state of the Universe when it is at the highest sustainable temperature. This state resolves the big-bang singularity by replacing the past of the hot big-bang Universe and sets inflationary initial conditions for the subsequent evolution of the thermal radiation and the semiclassical cosmological geometry. The entropy density in this state is equal to the square root of the energy density in Planck units, while the pressure is positive and equal to the energy density.
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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.
- Full Text:
- 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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Nuruddin Farah: variations on the theme of return
- 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.
- Full Text:
- 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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Nutrient patchiness, phytoplankton surge-uptake, and turbulent history: a theoretical approach and its experimental validation
- Schapira, Mathilde, Seuront, Laurent
- Authors: Schapira, Mathilde , Seuront, Laurent
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149774 , vital:38883 , https://doi.org/10.3390/fluids5020080
- Description: Despite ample evidence of micro- and small-scale (i.e., millimeter- to meter-scale) phytoplankton and zooplankton patchiness in the ocean, direct observations of nutrient distributions and the ecological importance of this phenomenon are still relatively scarce. In this context, we first describe a simple procedure to continuously sample nutrients in surface waters, and subsequently provide evidence of the existence of microscale distribution of ammonium in the ocean. We further show that ammonium is never homogeneously distributed, even under very high conditions of turbulence. Instead, turbulence intensity appears to control nutrient patchiness, with a more homogeneous or a more heterogeneous distribution observed under high and low turbulence intensities, respectively, under the same concentration in nutrient. Based on a modelling procedure taking into account the stochastic properties of intermittent nutrient distributions and observations carried out on natural phytoplankton communities, we introduce and verify the hypothesis that under nutrient limitation, the “turbulent history” of phytoplankton cells, i.e., the turbulent conditions they experienced in their natural environments, conditions their efficiency to uptake ephemeral inorganic nitrogen patches of different concentrations.
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- Authors: Schapira, Mathilde , Seuront, Laurent
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149774 , vital:38883 , https://doi.org/10.3390/fluids5020080
- Description: Despite ample evidence of micro- and small-scale (i.e., millimeter- to meter-scale) phytoplankton and zooplankton patchiness in the ocean, direct observations of nutrient distributions and the ecological importance of this phenomenon are still relatively scarce. In this context, we first describe a simple procedure to continuously sample nutrients in surface waters, and subsequently provide evidence of the existence of microscale distribution of ammonium in the ocean. We further show that ammonium is never homogeneously distributed, even under very high conditions of turbulence. Instead, turbulence intensity appears to control nutrient patchiness, with a more homogeneous or a more heterogeneous distribution observed under high and low turbulence intensities, respectively, under the same concentration in nutrient. Based on a modelling procedure taking into account the stochastic properties of intermittent nutrient distributions and observations carried out on natural phytoplankton communities, we introduce and verify the hypothesis that under nutrient limitation, the “turbulent history” of phytoplankton cells, i.e., the turbulent conditions they experienced in their natural environments, conditions their efficiency to uptake ephemeral inorganic nitrogen patches of different concentrations.
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Occurrence of selected endocrine disrupting compounds in the Eastern Cape province of South Africa:
- Farounbi, Adebayo I, Ngqwala, Nosiphiwe P
- Authors: Farounbi, Adebayo I , Ngqwala, Nosiphiwe P
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148447 , vital:38740 , DOI: 10.1007/s11356-020-08082-y
- Description: Endocrine-disrupting compounds are attracting attention worldwide because of their effects on living things in the environment. Ten endocrine disrupting compounds: 4-nonylphenol, 2,4-dichlorophenol, estrone, 17β-estradiol, bisphenol A, 4-tertoctylphenol, triclosan, atrazine, imidazole and 1,2,4-triazole were investigated in four rivers and wastewater treatment plants in this study. Rivers were sampled at upstream, midstream and downstream reaches, while the influent and effluent samples of wastewater were collected from treatment plants near the receiving rivers. Sample waters were freeze-dried followed by extraction of the organic content and purification by solid-phase extraction. Concentrations of the compounds in the samples were determined with ultra-high performance liquid chromatography-tandem mass spectrometry. The instrument was operated in the positive electrospray ionization (ESI) mode.
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- Authors: Farounbi, Adebayo I , Ngqwala, Nosiphiwe P
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148447 , vital:38740 , DOI: 10.1007/s11356-020-08082-y
- Description: Endocrine-disrupting compounds are attracting attention worldwide because of their effects on living things in the environment. Ten endocrine disrupting compounds: 4-nonylphenol, 2,4-dichlorophenol, estrone, 17β-estradiol, bisphenol A, 4-tertoctylphenol, triclosan, atrazine, imidazole and 1,2,4-triazole were investigated in four rivers and wastewater treatment plants in this study. Rivers were sampled at upstream, midstream and downstream reaches, while the influent and effluent samples of wastewater were collected from treatment plants near the receiving rivers. Sample waters were freeze-dried followed by extraction of the organic content and purification by solid-phase extraction. Concentrations of the compounds in the samples were determined with ultra-high performance liquid chromatography-tandem mass spectrometry. The instrument was operated in the positive electrospray ionization (ESI) mode.
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Photodynamic antimicrobial chemotherapy of a dimethylamino-functionalized asymmetric zinc (II) phthalocyanine and its quaternized derivative against Staphylococcus aureus when supported on asymmetric polystyrene polymer membranes:
- Mafukidze, Donovan M, Nyokong, Tebello
- Authors: Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148595 , vital:38753 , https://doi.org/10.1016/j.reactfunctpolym.2020.104634
- Description: Membrane applications are hindered by fouling. Photoactive membranes (containing photosensitizers) show photodynamic antimicrobial chemotherapy (PACT) activity which reduces biological fouling. In this work we use phthalocyanines (Pcs) as photosensitizers. The Pcs used are: 2-(4-carboxyphenoxy)-9(10), 16(17), 23(24)-tris(dimethylamino) phthalocyaninato zinc(II) (1) and the quaternized 2-(4-carboxyphenoxy)-9(10), 16(17), 23(24)-tris(trimethylamino) phthalocyanine zinc(II) methyl sulfate (2). Complex 2 showed an enhanced singlet oxygen quantum yield (ΦΔ) of 0.76 compared to 0.53 for 1. Complex 2 showed enhanced PACT activity against Staphylococcus aureus giving a log reduction value of 9.4, while its precursor (complex 1) gave 0.08. The complexes were then conjugated to amine-functionalized polystyrene and embedded into polystyrene to form membranes resulting in ΦΔ values of 0.24 and 0.27 for complexes 1 and 2 respectively in water. The latter membrane showed better PACT activity.
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- Authors: Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148595 , vital:38753 , https://doi.org/10.1016/j.reactfunctpolym.2020.104634
- Description: Membrane applications are hindered by fouling. Photoactive membranes (containing photosensitizers) show photodynamic antimicrobial chemotherapy (PACT) activity which reduces biological fouling. In this work we use phthalocyanines (Pcs) as photosensitizers. The Pcs used are: 2-(4-carboxyphenoxy)-9(10), 16(17), 23(24)-tris(dimethylamino) phthalocyaninato zinc(II) (1) and the quaternized 2-(4-carboxyphenoxy)-9(10), 16(17), 23(24)-tris(trimethylamino) phthalocyanine zinc(II) methyl sulfate (2). Complex 2 showed an enhanced singlet oxygen quantum yield (ΦΔ) of 0.76 compared to 0.53 for 1. Complex 2 showed enhanced PACT activity against Staphylococcus aureus giving a log reduction value of 9.4, while its precursor (complex 1) gave 0.08. The complexes were then conjugated to amine-functionalized polystyrene and embedded into polystyrene to form membranes resulting in ΦΔ values of 0.24 and 0.27 for complexes 1 and 2 respectively in water. The latter membrane showed better PACT activity.
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PKS 2250−351: A Giant Radio Galaxy in Abell 3936
- Seymour, N, Huynh, M, Shabala, S S, Rogers, J, Davies, L J M, Turner, R J, O'Brien, A, Ishwara-Chandra, C H, Thorne, J E, Galvin, T J, Jarrett, T, Anderbach, H, Anderson A, Bunton, J, Chow, K, Collier, J D, Driver, S, Filipovic, M D, Gurkan, G, Hopkins, A M, Kapinska, A D, Leahy, D A, Marvil, J, Manojlovic, P, Norris, R P, Phillips, C, Robotham, A, Rudnick, L, Singh, V, White, S V
- Authors: Seymour, N , Huynh, M , Shabala, S S , Rogers, J , Davies, L J M , Turner, R J , O'Brien, A , Ishwara-Chandra, C H , Thorne, J E , Galvin, T J , Jarrett, T , Anderbach, H , Anderson A , Bunton, J , Chow, K , Collier, J D , Driver, S , Filipovic, M D , Gurkan, G , Hopkins, A M , Kapinska, A D , Leahy, D A , Marvil, J , Manojlovic, P , Norris, R P , Phillips, C , Robotham, A , Rudnick, L , Singh, V , White, S V
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150320 , vital:38967 , https://doi.org/10.1017/pasa.2019.49
- Description: We present a detailed analysis of the radio galaxy PKS , a giant of 1.2 Mpc projected size, its host galaxy, and its environment. We use radio data from the Murchison Widefield Array, the upgraded Giant Metre-wavelength Radio Telescope, the Australian Square Kilometre Array Pathfinder, and the Australia Telescope Compact Array to model the jet power and age. Optical and IR data come from the Galaxy And Mass Assembly (GAMA) survey and provide information on the host galaxy and environment.
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- Authors: Seymour, N , Huynh, M , Shabala, S S , Rogers, J , Davies, L J M , Turner, R J , O'Brien, A , Ishwara-Chandra, C H , Thorne, J E , Galvin, T J , Jarrett, T , Anderbach, H , Anderson A , Bunton, J , Chow, K , Collier, J D , Driver, S , Filipovic, M D , Gurkan, G , Hopkins, A M , Kapinska, A D , Leahy, D A , Marvil, J , Manojlovic, P , Norris, R P , Phillips, C , Robotham, A , Rudnick, L , Singh, V , White, S V
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150320 , vital:38967 , https://doi.org/10.1017/pasa.2019.49
- Description: We present a detailed analysis of the radio galaxy PKS , a giant of 1.2 Mpc projected size, its host galaxy, and its environment. We use radio data from the Murchison Widefield Array, the upgraded Giant Metre-wavelength Radio Telescope, the Australian Square Kilometre Array Pathfinder, and the Australia Telescope Compact Array to model the jet power and age. Optical and IR data come from the Galaxy And Mass Assembly (GAMA) survey and provide information on the host galaxy and environment.
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Policies to reduce single-use plastic marine pollution in West Africa:
- Adam, Issahaku, Walker, Tony R, Bezerra, Joana Carlos, Clayton, Andrea
- Authors: Adam, Issahaku , Walker, Tony R , Bezerra, Joana Carlos , Clayton, Andrea
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150196 , vital:38948 , https://doi.org/10.1016/j.marpol.2020.103928
- Description: Countries in Africa are increasingly adopting policies to reduce single-use plastic (SUP) pollution, yet there has been limited analysis of policies adopted by African countries. This paper reviews SUP reduction policies, specifically in West Africa.
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- Authors: Adam, Issahaku , Walker, Tony R , Bezerra, Joana Carlos , Clayton, Andrea
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150196 , vital:38948 , https://doi.org/10.1016/j.marpol.2020.103928
- Description: Countries in Africa are increasingly adopting policies to reduce single-use plastic (SUP) pollution, yet there has been limited analysis of policies adopted by African countries. This paper reviews SUP reduction policies, specifically in West Africa.
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Post-release monitoring in classical biological control of weeds: higher trophic levels modify competitive interactions between invasive macrophytes
- Schaffner, Urs, Hill, Martin, Dudley, Tom, D’Antonio, Carla
- Authors: Schaffner, Urs , Hill, Martin , Dudley, Tom , D’Antonio, Carla
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150200 , vital:38949 , https://doi.org/10.1016/j.cois.2020.02.008
- Description: While various aspects of classical biological control (CBC) of weeds, including non-target risk assessment, have been continuously improved in the past few decades, post-release monitoring remains neglected and underfunded. Detailed assessments of the population, community and ecosystem outcomes of CBC introductions, including reasons for success/failure and absence or evidence of non-target effects are generally lacking or fragmentary. Here we review recent advances in understanding the demography of biological control agents released into a novel environment, their impact on the target weed and on non-target species, and the consequences for the resident plant and animal communities and ecosystem functioning, including the restoration of ecosystem services. We argue that post-release monitoring of CBC programs offers unique but largely underutilized opportunities to improve our understanding of CBC outcomes and to inform management and decision-makers on when and how CBC should be integrated with other management options to enhance ecosystem restoration.
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- Authors: Schaffner, Urs , Hill, Martin , Dudley, Tom , D’Antonio, Carla
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150200 , vital:38949 , https://doi.org/10.1016/j.cois.2020.02.008
- Description: While various aspects of classical biological control (CBC) of weeds, including non-target risk assessment, have been continuously improved in the past few decades, post-release monitoring remains neglected and underfunded. Detailed assessments of the population, community and ecosystem outcomes of CBC introductions, including reasons for success/failure and absence or evidence of non-target effects are generally lacking or fragmentary. Here we review recent advances in understanding the demography of biological control agents released into a novel environment, their impact on the target weed and on non-target species, and the consequences for the resident plant and animal communities and ecosystem functioning, including the restoration of ecosystem services. We argue that post-release monitoring of CBC programs offers unique but largely underutilized opportunities to improve our understanding of CBC outcomes and to inform management and decision-makers on when and how CBC should be integrated with other management options to enhance ecosystem restoration.
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Potential of soil seed bank and ungulate-mediated endozoochory in old field restoration:
- Authors: Ruwanza, Sheunesu
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150216 , vital:38950 , https://0-muse.jhu.edu.wam.seals.ac.za/article/750319/pdf
- Description: Soil seed bank plays a key role in old field restoration because it provides information about plant species that may regenerate (Hopfensperger 2007). Most studies on old field restoration have concentrated on floristic similarities between soil seed bank and standing vegetation (Török et al. 2018). However, investigating the effects of proximity to natural/old field edge (habitat fragmentation border) on soil seed bank could yield better recovery predictions. Proximity to natural/old field edge may favour recruitment of a different plant community than that found in the old field interior. This due to favorable abiotic (e.g., soil moisture) and biotic (e.g., seed dispersal) microenvironments created near the edge. On the other hand, ungulate-mediated endozoochory has been shown to potentially facilitate ecological restoration in degraded systems, given that ungulates disperse diaspores across different landscapes (Baltzinger et al. 2019). However, ungulate-mediated endozoochory dispersal in degraded old fields is affected by several factors that include availability of nearby natural perches that attract dispersers, structural vegetation complexities, presence of food especially fruits, and feeding regimes (Baltzinger et al. 2019).
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- Authors: Ruwanza, Sheunesu
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150216 , vital:38950 , https://0-muse.jhu.edu.wam.seals.ac.za/article/750319/pdf
- Description: Soil seed bank plays a key role in old field restoration because it provides information about plant species that may regenerate (Hopfensperger 2007). Most studies on old field restoration have concentrated on floristic similarities between soil seed bank and standing vegetation (Török et al. 2018). However, investigating the effects of proximity to natural/old field edge (habitat fragmentation border) on soil seed bank could yield better recovery predictions. Proximity to natural/old field edge may favour recruitment of a different plant community than that found in the old field interior. This due to favorable abiotic (e.g., soil moisture) and biotic (e.g., seed dispersal) microenvironments created near the edge. On the other hand, ungulate-mediated endozoochory has been shown to potentially facilitate ecological restoration in degraded systems, given that ungulates disperse diaspores across different landscapes (Baltzinger et al. 2019). However, ungulate-mediated endozoochory dispersal in degraded old fields is affected by several factors that include availability of nearby natural perches that attract dispersers, structural vegetation complexities, presence of food especially fruits, and feeding regimes (Baltzinger et al. 2019).
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PRECEPT: a framework for ethical digital forensics investigations
- Ferguson, R I, Renaud, Karen, Wilford, Sara, Irons, Alastair
- Authors: Ferguson, R I , Renaud, Karen , Wilford, Sara , Irons, Alastair
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149884 , vital:38909 , https://doi.org/10.1108/JIC-05-2019-00979
- Description: This paper argues the need for a practical, ethically grounded approach to digital forensic investigations, one that acknowledges and respects the privacy rights of individuals and the intellectual capital disclosure rights of organizations, as well as acknowledging the needs of law enforcement. The paper derives a set of ethical guidelines, and then maps these onto a forensics investigation framework. The framework to expert review in two stages is subjected, refining the framework after each stage. The paper concludes by proposing the refined ethically grounded digital forensics investigation framework. The treatise is primarily UK based, but the concepts presented here have international relevance and applicability.
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- Authors: Ferguson, R I , Renaud, Karen , Wilford, Sara , Irons, Alastair
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/149884 , vital:38909 , https://doi.org/10.1108/JIC-05-2019-00979
- Description: This paper argues the need for a practical, ethically grounded approach to digital forensic investigations, one that acknowledges and respects the privacy rights of individuals and the intellectual capital disclosure rights of organizations, as well as acknowledging the needs of law enforcement. The paper derives a set of ethical guidelines, and then maps these onto a forensics investigation framework. The framework to expert review in two stages is subjected, refining the framework after each stage. The paper concludes by proposing the refined ethically grounded digital forensics investigation framework. The treatise is primarily UK based, but the concepts presented here have international relevance and applicability.
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