Challenges experienced in the first year of implementation of a teaching and learning virtual partnership at the University of Namibia
- Mufeti, K, Foster, Gregory G, Terzoli, Alfredo
- Authors: Mufeti, K , Foster, Gregory G , Terzoli, Alfredo
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431234 , vital:72756 , https://rcetj.org/index.php/rcetj/article/view/178
- Description: Advances in information and communication technologies are enabling higher educa-tion institutions to build virtual partnerships with other institutions. Virtual partner-ships are defined here as collaborations between geographically dispersed institutions, where interaction between these institutions is enabled mainly by electronic modes of communication. This article reports on the participants’ experiences of the implemen-tation of one such partnership from the perspective of a partner in a developing con-text. It uses the SANTED Virtual Classroom Project (VCP), a virtual partnership initia-tive between the Departments of Computer Science at the University of Namibia (UNAM) and Rhodes University (RU), as a case study. In the VCP, the department at RU was tasked with building teaching and human resource capacity in the department at UNAM. The article focuses on the challenges experienced at UNAM during the first year of implementation of the VCP and lessons learned.
- Full Text:
- Authors: Mufeti, K , Foster, Gregory G , Terzoli, Alfredo
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431234 , vital:72756 , https://rcetj.org/index.php/rcetj/article/view/178
- Description: Advances in information and communication technologies are enabling higher educa-tion institutions to build virtual partnerships with other institutions. Virtual partner-ships are defined here as collaborations between geographically dispersed institutions, where interaction between these institutions is enabled mainly by electronic modes of communication. This article reports on the participants’ experiences of the implemen-tation of one such partnership from the perspective of a partner in a developing con-text. It uses the SANTED Virtual Classroom Project (VCP), a virtual partnership initia-tive between the Departments of Computer Science at the University of Namibia (UNAM) and Rhodes University (RU), as a case study. In the VCP, the department at RU was tasked with building teaching and human resource capacity in the department at UNAM. The article focuses on the challenges experienced at UNAM during the first year of implementation of the VCP and lessons learned.
- Full Text:
Characterization of 2,(3)-tetra-(4-oxo-benzamide) phthalocyaninato cobalt (II)—single walled carbon nanotube conjugate platforms and their use in electrocatalysis of amitrole
- Mugadza, Tawanda, Arslanoğlu, Yasin, Nyokong, Tebello
- Authors: Mugadza, Tawanda , Arslanoğlu, Yasin , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244382 , vital:51252 , xlink:href="https://doi.org/10.1016/j.electacta.2012.02.041"
- Description: In this paper we report on the use of carboxylic acid functionalized single walled carbon nanotubes (SWCNT) in the synthesis of 2,(3)-tetra-(4-oxo-benzamide)phthalocyaninato cobalt (II)–single walled carbon nanotube conjugates (CoTOBPc–SWCNT), their characterization and application in the electrocatalytic oxidation of amitrole. Cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy were used for the detection of amitrole on the modified glassy carbon electrode. The catalytic rate constant was 1.6 × 103 M−1 s−1 and the apparent electron rate transfer constant was 1.5 × 10−5 cm s−1. The linear dynamic range was 1.0 × 10−6–3.0 × 10−5 M, with a sensitivity of ∼1.13 A mol−1 L cm−2.
- Full Text:
- Authors: Mugadza, Tawanda , Arslanoğlu, Yasin , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244382 , vital:51252 , xlink:href="https://doi.org/10.1016/j.electacta.2012.02.041"
- Description: In this paper we report on the use of carboxylic acid functionalized single walled carbon nanotubes (SWCNT) in the synthesis of 2,(3)-tetra-(4-oxo-benzamide)phthalocyaninato cobalt (II)–single walled carbon nanotube conjugates (CoTOBPc–SWCNT), their characterization and application in the electrocatalytic oxidation of amitrole. Cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy were used for the detection of amitrole on the modified glassy carbon electrode. The catalytic rate constant was 1.6 × 103 M−1 s−1 and the apparent electron rate transfer constant was 1.5 × 10−5 cm s−1. The linear dynamic range was 1.0 × 10−6–3.0 × 10−5 M, with a sensitivity of ∼1.13 A mol−1 L cm−2.
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Comparison of carbon screen-printed and disk electrodes in the detection of antioxidants using CoPc derivatives
- Matemadombo, Fungisai, Apetrei, Constantin, Nyokong, Tebello, Rodríguez-Méndez, María Luz, de Saja, José Antonio
- Authors: Matemadombo, Fungisai , Apetrei, Constantin , Nyokong, Tebello , Rodríguez-Méndez, María Luz , de Saja, José Antonio
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244371 , vital:51251 , xlink:href="https://doi.org/10.1016/j.snb.2012.02.088"
- Description: Cobalt phthalocyanine (CoPc) and cobalt phthalocyanine carboxylic derivatives (CoTCPc and CoOCPc) have been used as electrocatalysts for the detection of the antioxidants vanillic acid, caffeic acid, pyrogallol, and ascorbic acid on screen-printed carbon and disk electrode surfaces. The cobalt phthalocyanines were used to detect vanillic acid (with limit of detection ranging from 1.15 μM to 2.42 μM at potentials of 0.55–0.88 V vs. Ag|AgCl), caffeic acid (with limit of detection ranging from 1.17 μM to 2.20 μM at potentials of 0.30–0.81 V vs. Ag|AgCl), pyrogallol (with limit of detection ranging from 1.16 μM to 3.63 μM at potentials of 0.52–0.63 V vs. Ag|AgCl), and ascorbic acid (with limit of detection ranging from 1.16 μM to 1.58 μM at potentials of 0.34–0.46 V vs. Ag|AgCl). The kinetic studies also demonstrate diffusion-controlled processes at the electrode surface. The SPCE electrodes have better detection properties towards vanillic acid, caffeic acid, pyrogallol while the disk electrodes had better ascorbic acid detection properties as proven by kinetic studies. Both types CoPc-influenced electrodes show 100% discrimination of the antioxidants.
- Full Text:
- Authors: Matemadombo, Fungisai , Apetrei, Constantin , Nyokong, Tebello , Rodríguez-Méndez, María Luz , de Saja, José Antonio
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244371 , vital:51251 , xlink:href="https://doi.org/10.1016/j.snb.2012.02.088"
- Description: Cobalt phthalocyanine (CoPc) and cobalt phthalocyanine carboxylic derivatives (CoTCPc and CoOCPc) have been used as electrocatalysts for the detection of the antioxidants vanillic acid, caffeic acid, pyrogallol, and ascorbic acid on screen-printed carbon and disk electrode surfaces. The cobalt phthalocyanines were used to detect vanillic acid (with limit of detection ranging from 1.15 μM to 2.42 μM at potentials of 0.55–0.88 V vs. Ag|AgCl), caffeic acid (with limit of detection ranging from 1.17 μM to 2.20 μM at potentials of 0.30–0.81 V vs. Ag|AgCl), pyrogallol (with limit of detection ranging from 1.16 μM to 3.63 μM at potentials of 0.52–0.63 V vs. Ag|AgCl), and ascorbic acid (with limit of detection ranging from 1.16 μM to 1.58 μM at potentials of 0.34–0.46 V vs. Ag|AgCl). The kinetic studies also demonstrate diffusion-controlled processes at the electrode surface. The SPCE electrodes have better detection properties towards vanillic acid, caffeic acid, pyrogallol while the disk electrodes had better ascorbic acid detection properties as proven by kinetic studies. Both types CoPc-influenced electrodes show 100% discrimination of the antioxidants.
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Cutaneous myiasis: is Lucilia cuprina safe and acceptable for maggot debridement therapy?
- Kingu, Howard J, Kuria, Simon K, Villet, Martin H, Mkhize, Jane N, Dhaffala, Adupa, Iisa, John M
- Authors: Kingu, Howard J , Kuria, Simon K , Villet, Martin H , Mkhize, Jane N , Dhaffala, Adupa , Iisa, John M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442649 , vital:74018 , DOI:10.4236/jcdsa.2012.22018
- Description: Preservation of viable tissue is important in wound management. It is achieved by small, incremental removal of devitalised, necrotic and infected tissues. Maggot debridement therapy (MDT) is used in septic necrotic wounds that fail to respond to conventional modalities. MDT has relied on Lucilia cuprina, which consumes only necrotic tissues, as opposed to Lucilia cuprina, which devours both flesh and necrotic tissues. Recent findings have shown that L. cuprina consumes mainly necrotic and very small amounts of viable tissues and may be used in MDT where L. sericata is very rare or absent. Here we describe wound healing in a patient from rural South Africa with cutaneous myiasis. Our findings agree with workers who indicated that L. cuprina could be used in MDT.
- Full Text:
- Authors: Kingu, Howard J , Kuria, Simon K , Villet, Martin H , Mkhize, Jane N , Dhaffala, Adupa , Iisa, John M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442649 , vital:74018 , DOI:10.4236/jcdsa.2012.22018
- Description: Preservation of viable tissue is important in wound management. It is achieved by small, incremental removal of devitalised, necrotic and infected tissues. Maggot debridement therapy (MDT) is used in septic necrotic wounds that fail to respond to conventional modalities. MDT has relied on Lucilia cuprina, which consumes only necrotic tissues, as opposed to Lucilia cuprina, which devours both flesh and necrotic tissues. Recent findings have shown that L. cuprina consumes mainly necrotic and very small amounts of viable tissues and may be used in MDT where L. sericata is very rare or absent. Here we describe wound healing in a patient from rural South Africa with cutaneous myiasis. Our findings agree with workers who indicated that L. cuprina could be used in MDT.
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DBU-Mediated cleavage of aryl-and heteroaryl disulfides
- Nyoni, Dubekile, Lobb, Kevin A, Kaye, Perry T, Cairab, Mino R
- Authors: Nyoni, Dubekile , Lobb, Kevin A , Kaye, Perry T , Cairab, Mino R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448884 , vital:74768
- Description: The capacity of the nitrogen nucleophile, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to reduce aryl- and heteroaryl disulfides to the corresponding mercaptans is demonstrated. While dicarboxylated disulfide analogues afford the mono-DBU disulfide salts, as confirmed by X-ray crystallography, the corresponding methyl esters are cleaved normally.
- Full Text:
- Authors: Nyoni, Dubekile , Lobb, Kevin A , Kaye, Perry T , Cairab, Mino R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448884 , vital:74768
- Description: The capacity of the nitrogen nucleophile, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to reduce aryl- and heteroaryl disulfides to the corresponding mercaptans is demonstrated. While dicarboxylated disulfide analogues afford the mono-DBU disulfide salts, as confirmed by X-ray crystallography, the corresponding methyl esters are cleaved normally.
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Effects of altered estuarine submerged macrophyte bed cover on the omnivorous Cape stumpnose Rhabdosargus holubi
- Sheppard, Jill N, Whitfield, Alan K, Cowley, Paul D, Hill, Jaclyn M
- Authors: Sheppard, Jill N , Whitfield, Alan K , Cowley, Paul D , Hill, Jaclyn M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444676 , vital:74259 , https://doi.org/10.1111/j.1095-8649.2011.03197.x
- Description: The ecological importance of submerged macrophyte beds to fishes within estuaries was investigated through the example of the ubiquitous Cape stumpnose Rhabdosargus holubi, an omnivorous, vegetation and estuary‐dependent species, using stable‐isotope techniques and long‐term abundance (catch‐per‐unit‐effort) data from the East Kleinemonde Estuary, South Africa. Outputs from a Bayesian mixing model using δ13C and δ15N signatures indicated that the submerged macrophytes Ruppia cirrhosa and Potamogeton pectinatus were not a primary source of nutrition for R. holubi, confirming previous work that revealed that macrophytes are consumed but not digested. Long‐term seine netting data showed reduced abundance of R. holubi during a prolonged period of macrophyte senescence, suggesting that submerged macrophyte habitats provide shelter that reduces mortality (predation risk) and a food‐rich foraging area.
- Full Text:
- Authors: Sheppard, Jill N , Whitfield, Alan K , Cowley, Paul D , Hill, Jaclyn M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444676 , vital:74259 , https://doi.org/10.1111/j.1095-8649.2011.03197.x
- Description: The ecological importance of submerged macrophyte beds to fishes within estuaries was investigated through the example of the ubiquitous Cape stumpnose Rhabdosargus holubi, an omnivorous, vegetation and estuary‐dependent species, using stable‐isotope techniques and long‐term abundance (catch‐per‐unit‐effort) data from the East Kleinemonde Estuary, South Africa. Outputs from a Bayesian mixing model using δ13C and δ15N signatures indicated that the submerged macrophytes Ruppia cirrhosa and Potamogeton pectinatus were not a primary source of nutrition for R. holubi, confirming previous work that revealed that macrophytes are consumed but not digested. Long‐term seine netting data showed reduced abundance of R. holubi during a prolonged period of macrophyte senescence, suggesting that submerged macrophyte habitats provide shelter that reduces mortality (predation risk) and a food‐rich foraging area.
- Full Text:
Electrocatalytic behavior of cobalt phthalocyanine complexes immobilized on glassy carbon electrode towards the reduction of dicrotophos pesticide
- Vilakazi, Sibulelo, Nyokong, Tebello, Fukuda, Takamitsu, Kobayashi, Nagao
- Authors: Vilakazi, Sibulelo , Nyokong, Tebello , Fukuda, Takamitsu , Kobayashi, Nagao
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245832 , vital:51409 , xlink:href="https://doi.org/10.1142/S1088424612501040"
- Description: Electrocatalytic properties of cobalt phthalocyanine (CoPc), cobalt tetra-carboxy phthalocyanine (CoTCPc) and cobalt octa-carboxy (CoOCPc), towards the detection of dicrotophos have been studied. Catalytic behavior towards the reduction of dicrotophos was found to be dependent on the pH, as well as the substitution on the phthalocyanine ring. Strong electron withdrawing groups on the phthalocyanine ring yielded best catalysis as evidenced by the enhancement of the reduction peak current, (~5 fold) compared to the bare glassy carbon electrode. The analysis gave a good detection limit of 1.25 × 10-7 M, and good linearity for the studied concentration range. A high Tafel slope value was obtained, indicating a strong interaction between dicrotophos and the cobalt phthalocyanine complex.
- Full Text:
- Authors: Vilakazi, Sibulelo , Nyokong, Tebello , Fukuda, Takamitsu , Kobayashi, Nagao
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245832 , vital:51409 , xlink:href="https://doi.org/10.1142/S1088424612501040"
- Description: Electrocatalytic properties of cobalt phthalocyanine (CoPc), cobalt tetra-carboxy phthalocyanine (CoTCPc) and cobalt octa-carboxy (CoOCPc), towards the detection of dicrotophos have been studied. Catalytic behavior towards the reduction of dicrotophos was found to be dependent on the pH, as well as the substitution on the phthalocyanine ring. Strong electron withdrawing groups on the phthalocyanine ring yielded best catalysis as evidenced by the enhancement of the reduction peak current, (~5 fold) compared to the bare glassy carbon electrode. The analysis gave a good detection limit of 1.25 × 10-7 M, and good linearity for the studied concentration range. A high Tafel slope value was obtained, indicating a strong interaction between dicrotophos and the cobalt phthalocyanine complex.
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Electrospun polyacrylic acid polymer fibers functionalized with metallophthalocyanines for photosensitizing and gas sensing applications
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243543 , vital:51162 , xlink:href="https://doi.org/10.1080/10601325.2012.662006"
- Description: The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas.
- Full Text:
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243543 , vital:51162 , xlink:href="https://doi.org/10.1080/10601325.2012.662006"
- Description: The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas.
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Facile deposition of gold nanoparticle thin films on semi-permeable cellulose substrate
- Sosibo, Ndabenhle, Mdluli, Phumlani, Mashazi, Philani N, Tshikhudo, Robert, Skepu, Amanda, Vilakazi, Sibulelo, Nyokong, Tebello
- Authors: Sosibo, Ndabenhle , Mdluli, Phumlani , Mashazi, Philani N , Tshikhudo, Robert , Skepu, Amanda , Vilakazi, Sibulelo , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/242638 , vital:51063 , xlink:href="https://doi.org/10.1016/j.matlet.2012.08.043"
- Description: This study reports the facile method for the deposition of gold nanoparticle thin film onto a monoporous semi-permeable cellulose membrane through the diffusion of borohydride ions leading to the reduction of AuCl4− ions. The synthesis of gold nanoparticle thin film was deposited on one side of the membrane that was exposed to AuCl4− ions while the other side containing a reducing agent remained clear. The gold nanoparticle thin film exhibited a broad surface plasmon resonance (SPR) peak at 529 nm. Various characterization techniques were employed and all demonstrated the presence of gold thin film. The reported method represents a simplistic method for the deposition of gold nanoparticle thin films and various other metal nanoparticles may be deposited following this method.
- Full Text:
- Authors: Sosibo, Ndabenhle , Mdluli, Phumlani , Mashazi, Philani N , Tshikhudo, Robert , Skepu, Amanda , Vilakazi, Sibulelo , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/242638 , vital:51063 , xlink:href="https://doi.org/10.1016/j.matlet.2012.08.043"
- Description: This study reports the facile method for the deposition of gold nanoparticle thin film onto a monoporous semi-permeable cellulose membrane through the diffusion of borohydride ions leading to the reduction of AuCl4− ions. The synthesis of gold nanoparticle thin film was deposited on one side of the membrane that was exposed to AuCl4− ions while the other side containing a reducing agent remained clear. The gold nanoparticle thin film exhibited a broad surface plasmon resonance (SPR) peak at 529 nm. Various characterization techniques were employed and all demonstrated the presence of gold thin film. The reported method represents a simplistic method for the deposition of gold nanoparticle thin films and various other metal nanoparticles may be deposited following this method.
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Fig wasps as vectors of mites and nematodes
- Jauharlina, J, Lindquist, E E, Quinnell, R J, Compton, Stephen G, Robertson, Hamish G
- Authors: Jauharlina, J , Lindquist, E E , Quinnell, R J , Compton, Stephen G , Robertson, Hamish G
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452076 , vital:75101 , https://hdl.handle.net/10520/EJC119300
- Description: Females of the pollinator fig wasp Elisabethiella baijnathi Wiebes carry mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs of Ficus burtt-davyi in Grahamstown, South Africa. The mites are phoretic on the outside of the wasps and phytophagous, feeding on galled flowers. The nematodes are transported inside the wasps and eventually eat them. Both mites and nematodes were present throughout the year. The prevalence (fig occupancy rates) of mites and nematodes in different crops ranged between zero and 100 %. Crop size did not influence the prevalence of either mites or nematodes. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators, and they may also utilize non-pollinating fig wasps as vectors.
- Full Text:
- Authors: Jauharlina, J , Lindquist, E E , Quinnell, R J , Compton, Stephen G , Robertson, Hamish G
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452076 , vital:75101 , https://hdl.handle.net/10520/EJC119300
- Description: Females of the pollinator fig wasp Elisabethiella baijnathi Wiebes carry mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs of Ficus burtt-davyi in Grahamstown, South Africa. The mites are phoretic on the outside of the wasps and phytophagous, feeding on galled flowers. The nematodes are transported inside the wasps and eventually eat them. Both mites and nematodes were present throughout the year. The prevalence (fig occupancy rates) of mites and nematodes in different crops ranged between zero and 100 %. Crop size did not influence the prevalence of either mites or nematodes. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators, and they may also utilize non-pollinating fig wasps as vectors.
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Firm age, collateral value, and access to debt financing in an emerging economy: evidence from South Africa
- Authors: Ezeoha,Abel , Botha, Ferdi
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396060 , vital:69147 , xlink:href="https://hdl.handle.net/10520/EJC31367"
- Description: This paper applies the Blundell and Bond system generalised method of moments (GMM) two-step estimator to examine the impact of age and collateral value on debt financing, using a panel of 177 non-financial companies listed on the Johannesburg Stock Exchange over the period 1999 to 2009. The results show that South African firms have target leverage ratios and adjust their capital structures from time to time to achieve their respective targets, that the relationship between firm age and debt financing is non-monotonic, and that firms with higher collateral value are likely to face fewer constraints on borrowing and therefore have greater access to medium-term and long-term debts. Robustness tests also reveal that during start-up and maturity stages, a firm's access to debt markets is significantly influenced by investments in assets that are acceptable to external creditors as collateral. These findings suggest that debt financing policies could be more critical for firms in the start-up and maturity stages.
- Full Text:
- Authors: Ezeoha,Abel , Botha, Ferdi
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396060 , vital:69147 , xlink:href="https://hdl.handle.net/10520/EJC31367"
- Description: This paper applies the Blundell and Bond system generalised method of moments (GMM) two-step estimator to examine the impact of age and collateral value on debt financing, using a panel of 177 non-financial companies listed on the Johannesburg Stock Exchange over the period 1999 to 2009. The results show that South African firms have target leverage ratios and adjust their capital structures from time to time to achieve their respective targets, that the relationship between firm age and debt financing is non-monotonic, and that firms with higher collateral value are likely to face fewer constraints on borrowing and therefore have greater access to medium-term and long-term debts. Robustness tests also reveal that during start-up and maturity stages, a firm's access to debt markets is significantly influenced by investments in assets that are acceptable to external creditors as collateral. These findings suggest that debt financing policies could be more critical for firms in the start-up and maturity stages.
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Geo-spatial autocorrelation as a metric for the detection of fast-flux botnet domains
- Stalmans, Etienne, Hunter, Samuel O, Irwin, Barry V W
- Authors: Stalmans, Etienne , Hunter, Samuel O , Irwin, Barry V W
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429799 , vital:72640 , 10.1109/ISSA.2012.6320433
- Description: Botnets consist of thousands of hosts infected with malware. Botnet owners communicate with these hosts using Command and Control (C2) servers. These C2 servers are usually infected hosts which the botnet owners do not have physical access to. For this reason botnets can be shut down by taking over or blocking the C2 servers. Botnet owners have employed numerous shutdown avoidance techniques. One of these techniques, DNS Fast-Flux, relies on rapidly changing address records. The addresses returned by the Fast-Flux DNS servers consist of geographically widely distributed hosts. The distributed nature of Fast-Flux botnets differs from legitimate domains, which tend to have geographically clustered server locations. This paper examines the use of spatial autocorrelation techniques based on the geographic distribution of domain servers to detect Fast-Flux domains. Moran's I and Geary's C are used to produce classifiers using multiple geographic co-ordinate systems to produce efficient and accurate results. It is shown how Fast-Flux domains can be detected reliably while only a small percentage of false positives are produced.
- Full Text:
- Authors: Stalmans, Etienne , Hunter, Samuel O , Irwin, Barry V W
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429799 , vital:72640 , 10.1109/ISSA.2012.6320433
- Description: Botnets consist of thousands of hosts infected with malware. Botnet owners communicate with these hosts using Command and Control (C2) servers. These C2 servers are usually infected hosts which the botnet owners do not have physical access to. For this reason botnets can be shut down by taking over or blocking the C2 servers. Botnet owners have employed numerous shutdown avoidance techniques. One of these techniques, DNS Fast-Flux, relies on rapidly changing address records. The addresses returned by the Fast-Flux DNS servers consist of geographically widely distributed hosts. The distributed nature of Fast-Flux botnets differs from legitimate domains, which tend to have geographically clustered server locations. This paper examines the use of spatial autocorrelation techniques based on the geographic distribution of domain servers to detect Fast-Flux domains. Moran's I and Geary's C are used to produce classifiers using multiple geographic co-ordinate systems to produce efficient and accurate results. It is shown how Fast-Flux domains can be detected reliably while only a small percentage of false positives are produced.
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Higher education, academic communities, and the intellectual virtues
- Authors: Jones, Ward E
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275647 , vital:55066 , xlink:href="https://doi.org/10.1111/edth.12005"
- Description: Because higher education brings members of academic communities in direct contact with students, the reflective higher education student is in an excellent position for developing two important intellectual virtues: confidence and humility. However, academic communities differ as to whether their members reach consensus, and their teaching practices reflect this difference. In this essay, Ward Jones argues that both consensus-reaching and non-consensus-reaching communities can encourage the development of intellectual confidence and humility in their students, although each will do so in very different ways.
- Full Text:
- Authors: Jones, Ward E
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275647 , vital:55066 , xlink:href="https://doi.org/10.1111/edth.12005"
- Description: Because higher education brings members of academic communities in direct contact with students, the reflective higher education student is in an excellent position for developing two important intellectual virtues: confidence and humility. However, academic communities differ as to whether their members reach consensus, and their teaching practices reflect this difference. In this essay, Ward Jones argues that both consensus-reaching and non-consensus-reaching communities can encourage the development of intellectual confidence and humility in their students, although each will do so in very different ways.
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How do HIV and AIDS impact the use of natural resources by poor rural populations?: The case of wild animal products
- Kaschula, Sarah, Shackleton, Charlie M
- Authors: Kaschula, Sarah , Shackleton, Charlie M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182344 , vital:43822 , xlink:href="https://hdl.handle.net/10520/EJC97203"
- Description: As a result of heightened financial and food insecurity, populations adversely affected by HIV and/or AIDS may be more likely to utilise wild natural resources to supplement their diet and livelihoods. Should this effect be pronounced, HIV and AIDS may pose a serious environmental threat. We explored the hypothesis that the presence of factors in the household, such as chronic illness in and recent mortality of individuals in a high HIV-risk age group, as well as the fostering of orphans, are associated with increased utilisation of wild animal products (WAPs) at the household level. We randomly surveyed 519 households from four sites in rural South Africa, recording household socio-economic status, the utilisation of wild animal products and health and demographic factors attributed to HIV or AIDS. Binary logistic regressions were used to test if households with markers of HIV and/or AIDS affliction were more likely to have a higher incidence and frequency of WAP utilisation relative to non-afflicted households, after adjusting for socio-economic and demographic variables. We found that, although households with markers of HIV and/or AIDS were generally poorer and had higher dependency ratios, there was no evidence to support the hypothesis that WAP harvesting was associated with either poverty, or markers of HIV and/or AIDS affliction. Our findings suggest that generalisations about a possible interaction between HIV and/or AIDS and the environment may not uniformly apply to all categories of natural resources or to all user groups.
- Full Text:
- Authors: Kaschula, Sarah , Shackleton, Charlie M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182344 , vital:43822 , xlink:href="https://hdl.handle.net/10520/EJC97203"
- Description: As a result of heightened financial and food insecurity, populations adversely affected by HIV and/or AIDS may be more likely to utilise wild natural resources to supplement their diet and livelihoods. Should this effect be pronounced, HIV and AIDS may pose a serious environmental threat. We explored the hypothesis that the presence of factors in the household, such as chronic illness in and recent mortality of individuals in a high HIV-risk age group, as well as the fostering of orphans, are associated with increased utilisation of wild animal products (WAPs) at the household level. We randomly surveyed 519 households from four sites in rural South Africa, recording household socio-economic status, the utilisation of wild animal products and health and demographic factors attributed to HIV or AIDS. Binary logistic regressions were used to test if households with markers of HIV and/or AIDS affliction were more likely to have a higher incidence and frequency of WAP utilisation relative to non-afflicted households, after adjusting for socio-economic and demographic variables. We found that, although households with markers of HIV and/or AIDS were generally poorer and had higher dependency ratios, there was no evidence to support the hypothesis that WAP harvesting was associated with either poverty, or markers of HIV and/or AIDS affliction. Our findings suggest that generalisations about a possible interaction between HIV and/or AIDS and the environment may not uniformly apply to all categories of natural resources or to all user groups.
- Full Text:
Imidazole-functionalized polymer microspheres and fibers–useful materials for immobilization of oxovanadium (IV) catalysts
- Walmsley, Ryan S, Ogunlaja, Adeniyi S, Coombes, Matthew J, Chidawanyika, Wadzanai J U, Litwinski, Christian, Torto, Nelson, Nyokong, Tebello, Tshentu, Zenixole R
- Authors: Walmsley, Ryan S , Ogunlaja, Adeniyi S , Coombes, Matthew J , Chidawanyika, Wadzanai J U , Litwinski, Christian , Torto, Nelson , Nyokong, Tebello , Tshentu, Zenixole R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/246041 , vital:51431 , xlink:href="https://doi.org/10.1039/C2JM15485D"
- Description: Both polymer microspheres and microfibers containing the imidazole functionality have been prepared and used to immobilize oxovanadium(IV). The average diameters and BET surface areas of the microspheres were 322 μm and 155 m2 g−1 while the fibers were 1.85 μm and 52 m2 g−1, respectively. XPS and microanalysis confirmed the incorporation of imidazole and vanadium in the polymeric materials. The catalytic activity of both materials was evaluated using the hydrogen peroxide facilitated oxidation of thioanisole. The microspheres were applied in a typical laboratory batch reactor set-up and quantitative conversions (>99%) were obtained in under 240 min with turn-over frequencies ranging from 21.89 to 265.53 h−1, depending on the quantity of catalyst and temperature. The microspherical catalysts also proved to be recyclable with no drop in activity being observed after three successive reactions. The vanadium functionalized fibers were applied in a pseudo continuous flow set-up. Factors influencing the overall conversion and product selectivity, including flow rate and catalyst quantity, were investigated. At flow rates of 1–4 mL h−1 near quantitative conversion was maintained over an extended period. Keeping the mass of catalyst constant (0.025 g) and varying the flow rate from 1–6 mL h−1 resulted in a shift in the formation of the oxidation product methyl phenyl sulfone from 60.1 to 18.6%.
- Full Text:
- Authors: Walmsley, Ryan S , Ogunlaja, Adeniyi S , Coombes, Matthew J , Chidawanyika, Wadzanai J U , Litwinski, Christian , Torto, Nelson , Nyokong, Tebello , Tshentu, Zenixole R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/246041 , vital:51431 , xlink:href="https://doi.org/10.1039/C2JM15485D"
- Description: Both polymer microspheres and microfibers containing the imidazole functionality have been prepared and used to immobilize oxovanadium(IV). The average diameters and BET surface areas of the microspheres were 322 μm and 155 m2 g−1 while the fibers were 1.85 μm and 52 m2 g−1, respectively. XPS and microanalysis confirmed the incorporation of imidazole and vanadium in the polymeric materials. The catalytic activity of both materials was evaluated using the hydrogen peroxide facilitated oxidation of thioanisole. The microspheres were applied in a typical laboratory batch reactor set-up and quantitative conversions (>99%) were obtained in under 240 min with turn-over frequencies ranging from 21.89 to 265.53 h−1, depending on the quantity of catalyst and temperature. The microspherical catalysts also proved to be recyclable with no drop in activity being observed after three successive reactions. The vanadium functionalized fibers were applied in a pseudo continuous flow set-up. Factors influencing the overall conversion and product selectivity, including flow rate and catalyst quantity, were investigated. At flow rates of 1–4 mL h−1 near quantitative conversion was maintained over an extended period. Keeping the mass of catalyst constant (0.025 g) and varying the flow rate from 1–6 mL h−1 resulted in a shift in the formation of the oxidation product methyl phenyl sulfone from 60.1 to 18.6%.
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In vitro photodynamic effect of aluminum tetrasulfophthalocyanines on melanoma skin cancer and healthy normal skin cells
- Maduray, Kaminee, Odhay, Bharti, Nyokong, Tebello
- Authors: Maduray, Kaminee , Odhay, Bharti , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245762 , vital:51403 , xlink:href="https://doi.org/10.1016/j.pdpdt.2011.07.001"
- Description: Photodynamic therapy is a medical treatment that uses an inactive dye/drug and lasers as a light source to activate the dye/drug to produce a toxic form of oxygen that destroys the cancer cells. This study aimed at investigating the cytotoxic effects of different concentrations of aluminum tetrasulfophthalocyanines in its inactive and active state (laser induced) on melanoma skin cancer cells, healthy normal skin fibroblast and keratinocyte cells. Experimentally, 3 x 10(4) cells/ml were seeded in 24-well plates before treatment with different concentrations of aluminum tetrasulfophthalocyanines. After 2 h, cells were irradiated with a light dose of 4.5 J/cm(2). Post-irradiated cells were incubated for 24 h before cell viability was measured using the CellTiter-Blue Viability Assay. Results showed that aluminum tetrasulfophthalocyanines at high concentrations were cytotoxic to melanoma cells in the absence of laser activation. In the presence of laser activation of aluminum tetrasulfophthalocyanines at a concentration of 40 mu g/ml decreased cell viability of melanoma cells to 45%, fibroblasts to 78% and keratinocytes to 73%. At this photosensitizing concentration of aluminum tetrasulfophthalocyanines the efficacy of the treatment light dose 4.5 J/cm(2) and the cell death mechanism induced by photoactivated aluminum tetrasulfophthalocyanines was evaluated. A light dose of 4.5 J/cm(2) was more efficient in killing a higher number of melanoma cells and a lower number of fibroblast and keratinocyte cells than the other light doses of 2.5 J/cm(2), 7.5 J/cm(2) and 10.5 J/cm(2). Apoptosis features such as blebbing, nucleus condensation, nucleus fragmentation and the formation of apoptotic bodies were seen in the photodynamic therapy treated melanoma skin cancer cells. This in vitro photodynamic therapy study concludes that using aluminum tetrasulfophthalocyanines at a photosensitizing concentration of 40 mu g/ml in combination with a laser dose of 4.5 J/cm(2) was potentially lethal for melanoma skin cancer cells and less harmful for the normal healthy skin cells. (c) 2011 Elsevier B.V. All rights reserved.
- Full Text:
- Authors: Maduray, Kaminee , Odhay, Bharti , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245762 , vital:51403 , xlink:href="https://doi.org/10.1016/j.pdpdt.2011.07.001"
- Description: Photodynamic therapy is a medical treatment that uses an inactive dye/drug and lasers as a light source to activate the dye/drug to produce a toxic form of oxygen that destroys the cancer cells. This study aimed at investigating the cytotoxic effects of different concentrations of aluminum tetrasulfophthalocyanines in its inactive and active state (laser induced) on melanoma skin cancer cells, healthy normal skin fibroblast and keratinocyte cells. Experimentally, 3 x 10(4) cells/ml were seeded in 24-well plates before treatment with different concentrations of aluminum tetrasulfophthalocyanines. After 2 h, cells were irradiated with a light dose of 4.5 J/cm(2). Post-irradiated cells were incubated for 24 h before cell viability was measured using the CellTiter-Blue Viability Assay. Results showed that aluminum tetrasulfophthalocyanines at high concentrations were cytotoxic to melanoma cells in the absence of laser activation. In the presence of laser activation of aluminum tetrasulfophthalocyanines at a concentration of 40 mu g/ml decreased cell viability of melanoma cells to 45%, fibroblasts to 78% and keratinocytes to 73%. At this photosensitizing concentration of aluminum tetrasulfophthalocyanines the efficacy of the treatment light dose 4.5 J/cm(2) and the cell death mechanism induced by photoactivated aluminum tetrasulfophthalocyanines was evaluated. A light dose of 4.5 J/cm(2) was more efficient in killing a higher number of melanoma cells and a lower number of fibroblast and keratinocyte cells than the other light doses of 2.5 J/cm(2), 7.5 J/cm(2) and 10.5 J/cm(2). Apoptosis features such as blebbing, nucleus condensation, nucleus fragmentation and the formation of apoptotic bodies were seen in the photodynamic therapy treated melanoma skin cancer cells. This in vitro photodynamic therapy study concludes that using aluminum tetrasulfophthalocyanines at a photosensitizing concentration of 40 mu g/ml in combination with a laser dose of 4.5 J/cm(2) was potentially lethal for melanoma skin cancer cells and less harmful for the normal healthy skin cells. (c) 2011 Elsevier B.V. All rights reserved.
- Full Text:
Inferring direct DNA binding from ChIP-seq
- Bailey, Timothy L, Machanick, Philip
- Authors: Bailey, Timothy L , Machanick, Philip
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439314 , vital:73565 , https://doi.org/10.1093/nar/gks433
- Description: Genome-wide binding data from transcription factor ChIP-seq experiments is the best source of information for inferring the relative DNA-binding affinity of these proteins in vivo . However, standard motif enrichment analysis and motif discovery approaches sometimes fail to correctly identify the binding motif for the ChIP-ed factor. To overcome this problem, we propose ‘central motif enrichment analysis’ (CMEA), which is based on the observation that the positional distribution of binding sites matching the direct-binding motif tends to be unimodal, well centered and maximal in the precise center of the ChIP-seq peak regions. We describe a novel visualization and statistical analysis tool—CentriMo—that identifies the region of maximum central enrichment in a set of ChIP-seq peak regions and displays the positional distributions of predicted sites. Using CentriMo for motif enrichment analysis, we provide evidence that one transcription factor (Nanog) has different binding affinity in vivo than in vitro , that another binds DNA cooperatively (E2f1), and confirm the in vivo affinity of NFIC, rescuing a difficult ChIP-seq data set. In another data set, CentriMo strongly suggests that there is no evidence of direct DNA binding by the ChIP-ed factor (Smad1). CentriMo is now part of the MEME Suite software package available at http://meme.nbcr.net . All data and output files presented here are available at: http://research.imb.uq.edu.au/t.bailey/sd/Bailey2011a .
- Full Text:
- Authors: Bailey, Timothy L , Machanick, Philip
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439314 , vital:73565 , https://doi.org/10.1093/nar/gks433
- Description: Genome-wide binding data from transcription factor ChIP-seq experiments is the best source of information for inferring the relative DNA-binding affinity of these proteins in vivo . However, standard motif enrichment analysis and motif discovery approaches sometimes fail to correctly identify the binding motif for the ChIP-ed factor. To overcome this problem, we propose ‘central motif enrichment analysis’ (CMEA), which is based on the observation that the positional distribution of binding sites matching the direct-binding motif tends to be unimodal, well centered and maximal in the precise center of the ChIP-seq peak regions. We describe a novel visualization and statistical analysis tool—CentriMo—that identifies the region of maximum central enrichment in a set of ChIP-seq peak regions and displays the positional distributions of predicted sites. Using CentriMo for motif enrichment analysis, we provide evidence that one transcription factor (Nanog) has different binding affinity in vivo than in vitro , that another binds DNA cooperatively (E2f1), and confirm the in vivo affinity of NFIC, rescuing a difficult ChIP-seq data set. In another data set, CentriMo strongly suggests that there is no evidence of direct DNA binding by the ChIP-ed factor (Smad1). CentriMo is now part of the MEME Suite software package available at http://meme.nbcr.net . All data and output files presented here are available at: http://research.imb.uq.edu.au/t.bailey/sd/Bailey2011a .
- Full Text:
Interaction of CdTe quantum dots with 2, 2-diphenyl-1-picrylhydrazyl free radical
- Adegoke, Oluwasesan, Chidawanyika, Wadzanai J U, Nyokong, Tebello
- Authors: Adegoke, Oluwasesan , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245751 , vital:51402 , xlink:href="https://doi.org/10.1007/s10895-011-1012-2"
- Description: The interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH●) free radical with thiol-capped CdTe quantum dots (QDs) has been studied by UV–vis spectroscopy, steady state and time resolved fluorescence measurements. Addition of DPPH● radical to CdTe QDs resulted in fluorescence quenching. The interaction occurs through static quenching as this was confirmed by fluorescence lifetime measurements. Time course absorption studies indicates that DPPH● may be reduced by interaction with QDs to the substituted hydrazine form (2,2-diphenyl-1-picrylhydrazine) DPPH-H. The mechanism of fluorescence quenching of CdTe QDs by DPPH● is proposed.
- Full Text:
- Authors: Adegoke, Oluwasesan , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245751 , vital:51402 , xlink:href="https://doi.org/10.1007/s10895-011-1012-2"
- Description: The interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH●) free radical with thiol-capped CdTe quantum dots (QDs) has been studied by UV–vis spectroscopy, steady state and time resolved fluorescence measurements. Addition of DPPH● radical to CdTe QDs resulted in fluorescence quenching. The interaction occurs through static quenching as this was confirmed by fluorescence lifetime measurements. Time course absorption studies indicates that DPPH● may be reduced by interaction with QDs to the substituted hydrazine form (2,2-diphenyl-1-picrylhydrazine) DPPH-H. The mechanism of fluorescence quenching of CdTe QDs by DPPH● is proposed.
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Investigating water knowledge flow to communities
- Burt, Jane C, Berold, Robert
- Authors: Burt, Jane C , Berold, Robert
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433013 , vital:72923 , xlink:href="https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/KV%20288-11.pdf"
- Description: Those of us who work in water resource management have found that very few knowledge/research resources are accessible to most people. This happens because resources are not disseminated properly (or at all), or because they are inappropriately technicist, or because potential readers are hampered by low education. What is the best way to make water research accessible to as many people as possible and especially to people whose lives would be affected by the research? In the early 1980s an attempt was made to address this issue when Robert Berold edited People's Workbook (EDA 1981), a user-friendly book that presented basic technical information for rural people – not only on water, but also on agriculture, health, building construction, and income generation. The book included real-life interviews, and was disseminated by rural fieldworkers. Perhaps because there was nothing like it at the time, it was enormously popular.
- Full Text:
- Authors: Burt, Jane C , Berold, Robert
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433013 , vital:72923 , xlink:href="https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/KV%20288-11.pdf"
- Description: Those of us who work in water resource management have found that very few knowledge/research resources are accessible to most people. This happens because resources are not disseminated properly (or at all), or because they are inappropriately technicist, or because potential readers are hampered by low education. What is the best way to make water research accessible to as many people as possible and especially to people whose lives would be affected by the research? In the early 1980s an attempt was made to address this issue when Robert Berold edited People's Workbook (EDA 1981), a user-friendly book that presented basic technical information for rural people – not only on water, but also on agriculture, health, building construction, and income generation. The book included real-life interviews, and was disseminated by rural fieldworkers. Perhaps because there was nothing like it at the time, it was enormously popular.
- Full Text:
Is there no urban forestry in the developing world?
- Authors: Shackleton, Charlie M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181060 , vital:43695 , xlink:href="https://doi.org/10.5897/SRE11.1117"
- Description: Urban forestry and greening offer a multitude of benefits to the inhabitants of towns and cities. However, the nature and magnitude of these frequently depend upon the context. Yet, at first glance, the developing world context around urban forestry debates seems to be poorly represented in the international peer-reviewed literature. This is examined in this paper, followed by a brief outline of ten key research areas for urban forestry in the developing world. A survey of the peer-reviewed literature confirms that almost 80% of articles come from the developed world context. This correlates with the greater availability of research finance and personnel from developed regions. However, there are urban forestry questions and issues that require examination in the developing world because they cannot simply be transferred from knowledge gleaned from and tested in a developed world context. Ten of these are briefly outlined as a catalyst towards greater attention to urban forestry in the developing world and their contributions to global debates and models.
- Full Text:
- Authors: Shackleton, Charlie M
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181060 , vital:43695 , xlink:href="https://doi.org/10.5897/SRE11.1117"
- Description: Urban forestry and greening offer a multitude of benefits to the inhabitants of towns and cities. However, the nature and magnitude of these frequently depend upon the context. Yet, at first glance, the developing world context around urban forestry debates seems to be poorly represented in the international peer-reviewed literature. This is examined in this paper, followed by a brief outline of ten key research areas for urban forestry in the developing world. A survey of the peer-reviewed literature confirms that almost 80% of articles come from the developed world context. This correlates with the greater availability of research finance and personnel from developed regions. However, there are urban forestry questions and issues that require examination in the developing world because they cannot simply be transferred from knowledge gleaned from and tested in a developed world context. Ten of these are briefly outlined as a catalyst towards greater attention to urban forestry in the developing world and their contributions to global debates and models.
- Full Text: