Successful identification of the final instar nymph of Quintilia carinata (Thunberg)(Hemiptera: Cicadidae) by DNA extraction from the exuvium
- Authors: Bouwer, Nicolette , Midgley, John M , Timm, Alicia E , Villet, Martin H
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442347 , vital:73977 , https://doi.org/10.1080/00222933.2013.836759
- Description: Despite being taxonomically and phylogenetically informative, the morphology of the immature stages of cicadas has received comparatively superficial attention. One reason for this is the difficulty of positively identifying immature stages, particularly as these stages are fossorial. We present a method for identifying cicada exuviae using DNA sequence data and describe a set of characters and character states for the final instar nymph of Quintilia carinata (Thunberg). The identification of immature stages using molecular methods will increase our knowledge of African cicadas, allowing for the initiation of future phylogenetic and ecological comparisons.
- Full Text:
- Date Issued: 2014
Synthesis and characterization of novel zinc phthalocyanines as potential photosensitizers for photodynamic therapy of cancers
- Authors: Moeno, Sharon , Ermilov, E A , Kuzyniak, W , Höpfner, M , Krause, Rui W M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123673 , vital:35471 , https://doi.org/10.1039/C3PP50393C
- Description: Two novel zinc phthalocyanines (Pcs): tetramethyl tetrakis-2,(3)-[(4-methyl-2-pyridyloxy)phthalocyaninato] zinc(II) (4) and (the negatively charged form) tetrakis-2,(3)-[(3-carboxylicacid-6-sulfanylpyridine)phthalocyaninato] zinc(II) (5), water soluble by virtue of their ionic substituent groups were synthesized. The spectroscopic properties of both compounds were determined and their photodynamic activities were investigated in a human tumor cell model. In aqueous media the two peripherally substituted water soluble Pcs are highly aggregated. The phototoxic activity of the two novel Pcs (Pc 4 and Pc 5; 0–20 μM) was shown to be time- and dose-dependent in human pancreatic carcinoid BON cells, leading to a reduction of tumor cells of >80% compared to the controls. The effectiveness of the treatment appeared to be attenuated by the aggregation of Pcs under aqueous conditions. Interestingly, even those cells that were not immediately killed by the photoactivated photosensitizer seemed to be affected by the Pc photodynamic activity, as a single PDT induced long-lasting effects on cell survival. Even 4 days after PDT, the number of surviving cells did not re-increase or still dropped, as compared to control cells. The underlying mechanism of this observation has to be deciphered in future investigations.
- Full Text:
- Date Issued: 2014
VC's welcome at the Rhodes University house committees and sub-wardens workshop
- Authors: Badat, Saleem
- Date: 2013-01-30
- Language: English
- Type: Text
- Identifier: vital:7914 , http://hdl.handle.net/10962/d1016464
- Full Text:
- Date Issued: 2013-01-30
A high-level architecture for efficient packet trace analysis on gpu co-processors
- Authors: Nottingham, Alastair , Irwin, Barry V W
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429572 , vital:72623 , 10.1109/ISSA.2013.6641052
- Description: This paper proposes a high-level architecture to support efficient, massively parallel packet classification, filtering and analysis using commodity Graphics Processing Unit (GPU) hardware. The proposed architecture aims to provide a flexible and efficient parallel packet processing and analysis framework, supporting complex programmable filtering, data mining operations, statistical analysis functions and traffic visualisation, with minimal CPU overhead. In particular, this framework aims to provide a robust set of high-speed analysis functionality, in order to dramatically reduce the time required to process and analyse extremely large network traces. This architecture derives from initial research, which has shown GPU co-processors to be effective in accelerating packet classification to up to tera-bit speeds with minimal CPU overhead, far exceeding the bandwidth capacity between standard long term storage and the GPU device. This paper provides a high-level overview of the proposed architecture and its primary components, motivated by the results of prior research in the field.
- Full Text:
- Date Issued: 2013
Automated classification of computer network attacks
- Authors: van Heerden, Renier , Leenen, Louise , Irwin, Barry V W
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429622 , vital:72627 , 10.1109/ICASTech.2013.6707510
- Description: In this paper we demonstrate how an automated reasoner, HermiT, is used to classify instances of computer network based attacks in conjunction with a network attack ontology. The ontology describes different types of network attacks through classes and inter-class relationships and has previously been implemented in the Protege ontology editor. Two significant recent instances of network based attacks are presented as individuals in the ontology and correctly classified by the automated reasoner according to the relevant types of attack scenarios depicted in the ontology. The two network attack instances are the Distributed Denial of Service attack on SpamHaus in 2013 and the theft of 42 million Rand ($6.7 million) from South African Postbank in 2012.
- Full Text:
- Date Issued: 2013
Classification of security operation centers
- Authors: Jacobs, Pierre , Arnab, Alapan , Irwin, Barry V W
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429635 , vital:72628 , 10.1109/ISSA.2013.6641054
- Description: Security Operation Centers (SOCs) are a necessary service for organisations that want to address compliance and threat management. While there are frameworks in existence that addresses the technology aspects of these services, a holistic framework addressing processes, staffing and technology currently do not exist. Additionally, it would be useful for organizations and constituents considering building, buying or selling these services to measure the effectiveness and maturity of the provided services. In this paper, we propose a classification and rating scheme for SOC services, evaluating both the capabilities and the maturity of the services offered.
- Full Text:
- Date Issued: 2013
Classification of security operation centers
- Authors: Jacobs, Pierre , Arnab, Alapan , Irwin, Barry V W
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429785 , vital:72639 , 10.1109/ISSA.2013.6641054
- Description: Security Operation Centers (SOCs) are a necessary service for organisations that want to address compliance and threat management. While there are frameworks in existence that addresses the technology aspects of these services, a holistic framework addressing processes, staffing and technology currently do not exist. Additionally, it would be useful for organizations and constituents considering building, buying or selling these services to measure the effectiveness and maturity of the provided services. In this paper, we propose a classification and rating scheme for SOC services, evaluating both the capabilities and the maturity of the services offered.
- Full Text:
- Date Issued: 2013
Customising a BBVC for Asterisk VoIP Services
- Authors: Oyedele, Y , Terzoli, Alfredo , Mufeti, K
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430942 , vital:72730 , https://doi.org/10.1007/978-1-4614-3558-7_62
- Description: Browser-based Voice over Internet Protocol Clients (BBVC) are used to access pre-determined VoIP services from VoIP service providers through Internet connections. For nomadic users within an organisa-tion’s Intranet, connections are made to the Internet to utilise these BBVC. An Intranet with an Asterisk Private Branch Exchange (PBX) as a VoIP provider however can be linked with any form of VoIP client to improve service accessibility for its users. This study aims to find a BBVC that can be customised to provide such accessibility within an Intranet. The study revealed that three BBVC are compatible. One of three BBVC was selected for customisation to provide nomadic acces-sibility to Asterisk. The functionality of the customised BBVC depended on the web technologies used and the available VoIP services.
- Full Text:
- Date Issued: 2013
Environmental ethics as processes of open-ended, pluralistic, deliberative enquiry
- Authors: Olvitt, Lausanne L
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437309 , vital:73368 , ISBN 9780203813331 , https://www.taylorfrancis.com/chapters/edit/10.4324/9780203813331-15/environmental-ethics-processes-open-ended-pluralistic-deliberative-enquiry-lausanne-olvitt
- Description: By the very nature of their work, environmental education re-searchers must engage with environmental philosophy and questions of values and ethics. But this terrain, despite being resourced with an apparently endless supply of typologies, an-thologies, and handbooks, can remain a vast and daunting philosophical sea—at least in my experience as a newcomer to the field, and possibly for many other scholars and re-searchers. This essay makes no claim to altering that and in-stead optimistically pursues Ball’s (2001, p. 89) suggestion that “there is much to be learned about, and from, the philosophical life-forms inhabiting these thickets and swamps.” My intention here is to review a relatively small but growing cluster of work in environmental ethics that proposes that:“Ethical positions are always open for discussion, re-examination, and revi-sion”(Jickling, 2004, p. 16) and are thus, by their very nature, open-ended, relational processes. My starting point in writing this essay is as an educator-researcher-environmentalist trying to explore what the field of environmental ethics has to offer in response to the question:“As educators, how can we learn and do more with others in the face of an unprecedented socioeco-logical crisis?”
- Full Text:
- Date Issued: 2013
TeleWeaver: an innovative telecommunication platform for marginalized communities in Africa
- Authors: Dalvit, Lorenzo , Gumbo, Sibukelo , Ntshinga, Lindikaya , Terzoli, Alfredo , Hansen, Susan
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431317 , vital:72763 , https://www.academic-bookshop.com/ourshop/prod_2659103-ECEG-2013-13th-European-Conference-on-eGovernment-Como-Italy-PRINT-version.html
- Description: Information and Communication Technologies for Development (ICT4D) is becoming an increasingly important and multi‐faceted area of research and software development. Particularly through provision via mobile devices, e‐services can potentially reach and improve the lives of millions of people living in marginalised areas. The efforts of many governments in sub‐Saharan Africa are frustrated by poor tele-communication infrastructure, lack of skills and unsustainable models of intervention. In this paper we describe the holistic solution offered by the TeleWeaver platform. The novel approach to the development of the software, the strong sense of social responsibility of the developers and the collaborative spirit that shaped the ecosystem of which Tele-Weaver is part, warrants the adoption of an innovative approach to its marketing and implementation. On the one hand, the project needs to provide returns on investment and generate profit for the key stake-holders (ie government at the local and national level, academia, indus-try and socio‐-entrepreneurs in the target community). On the other, it must benefit all members of the marginalised communities it is intended to serve as well as the global community of software developers. Tele-Weaver was developed in close collaboration with the community of Dwesa, a rural area on the Wild Cost of the Transkei regions in eastern South Africa.
- Full Text:
- Date Issued: 2013
The African coelacanth genome provides insights into tetrapod evolution:
- Authors: Amemiya, Chris T , Alföldi, Jessica , Lee, Alison P , Fan, Shaohua , Philippe, Herve´ , MacCallum, Iain , Braasch, Ingo , Manousaki, Tereza , Schneider, Igor , Rohner, Nicolas , Organ, Chris , Chalopin, Domitille , Smith, Jeramiah J , Robinson, Mark , Dorrington, Rosemary A , Gerdol, Marco , Aken, Bronwen , Biscotti, Maria Assunta , Barucca, Marco , Baurain, Denis , Berlin, Aaron , Blatch, Gregory L , Buonocore, Francesco , Burmester, Thorsten , Campbell, Michael S , Canapa, Adriana , Cannon, John P , Christoffels, Alan , De Moro, Gianluca , Edkins, Adrienne L , Fan, Lin , Fausto, Anna Maria , Feiner, Nathalie , Forconi, Mariko , Gamieldien, Junaid , Gnerre, Sante , Gnirke, Andreas , Goldstone, Jared V , Haerty, Wilfried , Hahn, Mark E , Hesse, Uljana , Hoffmann, Steve , Johnson, Jeremy , Karchner, Sibel I , Kuraku, Shigehiro , Lara, Marcia , Levin, Joshua Z , Litman, Gary W , Mauceli, Evan , Miyake, Tsutomu , Mueller, M Gail , Nelson, David R , Nitsche, Anne , Olmo, Ettore , Ota, Tatsuya , Pallavicini, Alberto , Panji, Sumir , Picone, Barbara , Ponting, Chris P , Prohaska, Sonja J , Przybylski, Dariusz , Ratan Saha, Nil , Ravi, Vydianathan , Ribeiro, Filipe J , Sauka-Spengler, Tatjana , Scapigliati, Giuseppe , Searle, Stephen M J , Sharpe, Ted , Simakov, Oleg , Stadler, Peter F , Stegeman, John J , Sumiyama, Kenta , Tabbaa, Diana , Tafer, Hakim , Turner-Maier, Jason , van Heusden, Peter , White, Simon , Williams, Louise , Yandell, Mark , Brinkmann, Henner , Volff, Jean-Nicolas , Tabin, Clifford J , Shubin, Neil , Schartl, Manfred , Jaffe, David B , Postlethwait, John H , Venkatesh, Byrappa , Di Palma, Frederica , Lander, Eric S , Meyer, Axel , Lindblad-Toh, Kerstin
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165030 , vital:41202 , DOI: 10.1038/nature12027
- Description: The discovery of a living coelacanth specimen in 1938 was remarkable, as this lineage of lobe-finned fish was thought to have become extinct 70 million years ago. The modern coelacanth looks remarkably similar to many of its ancient relatives, and its evolutionary proximity to our own fish ancestors provides a glimpse of the fish that first walked on land. Here we report the genome sequence of the African coelacanth, Latimeria chalumnae. Through a phylogenomic analysis, we conclude that the lungfish, and not the coelacanth, is the closest living relative of tetrapods. Coelacanth protein-coding genes are significantly more slowly evolving than those of tetrapods, unlike other genomic features. Analyses of changes in genes and regulatory elements during the vertebrate adaptation to land highlight genes involved in immunity, nitrogen excretion and the development of fins, tail, ear, eye, brain and olfaction. Functional assays of enhancers involved in the fin-to-limb transition and in the emergence of extra-embryonic tissues show the importance of the coelacanth genome as a blueprint for understanding tetrapod evolution.
- Full Text:
- Date Issued: 2013
A hundred years of History at Rhodes University: some reflections on the department's centenary colloquium, September 2011 reminiscences
- Authors: Maylam, Paul
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450012 , vital:74875 , https://www.scielo.org.za/pdf/hist/v57n1/09.pdf
- Description: In 1911, W.M. Macmillan, who would become the most distinguished South Africanist historian of his generation, was appointed as the first lecturer in History (and Economics) at what was then Rhodes University College. To mark the centenary of its founding the Rhodes History Department held a two-day colloquium on 16-17 September 2011. The event brought together almost 50 current and former staff and students. Some delivered papers reflecting on the history of the department; others spoke about their present research interests. Among the participants there was a representative from every decade since the 1940s - Rodney Davenport having been a student in the department from 1943.
- Full Text:
- Date Issued: 2012
Geo-spatial autocorrelation as a metric for the detection of fast-flux botnet domains
- 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:
- Date Issued: 2012
Introducing the monograph and the (re)views
- Authors: Lotz-Sisitka, Heila
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/436623 , vital:73287 , ISBN 978-1-919991-81-8 , https://transformativelearning.education/wp-content/uploads/2013/01/reviews-on-social-learning-literature.pdf
- Description: This monograph, entitled (Re) Views on Social Learning Literature: A monograph for social learning researchers in natural resources manage-ment and environmental education provides four different reviews on the social learning literature. Rather than seeking to be comprehensive, the reviews seek to provide views on the social learning literature, from dif-ferent perspectives. The purpose of the monograph is to scope aspects of the social learning literature, providing access to a wide body of litera-ture(s) on social learning for emerging researchers interested in social learning in the fields of environmental education and natural resources management.
- Full Text:
- Date Issued: 2012
The fitting problem in a lattice Universe
- Authors: Larena, Julien
- Date: 2012
- Language: English
- Type: Text
- Identifier: vital:6780 , http://hdl.handle.net/10962/d1012405
- Description: We present a regular cubic lattice solution to Einstein field equations that is exact at second order in a small parameter. We show that this solution is kinematically equivalent to the Friedmann-Lemaitre-Robertson-Walker (FLRW) solution with the same averaged energy density. This allows us to discuss the fitting problem in that framework: are observables along the past lightcone of observers equivalent to those in the analogue FLRW model obtained by smoothing spatially the distribution of matter? We find a criterion on the compacity of the objects that must be satisfied in order for the answer to this question to be positive and given by perturbative arguments. If this criterion is not met, the answer to this question must be addressed fully non perturbatively along the past lightcone, even though the spacetime geometry can be described perturbatively. , Prepared for the Proceedings of the conference 'Relativity and Gravitation: 100 years after Einstein in Prague', Prague, 25-29th June 2012.
- Full Text:
- Date Issued: 2012
Inorganic Chemistry 2: PAC 321
- Authors: Ajibade, P A , Purcell, W
- Date: 2012-01
- Language: English
- Type: Examination paper
- Identifier: vital:17822 , http://hdl.handle.net/10353/d1010375
- Description: Inorganic Chemistry 2: PAC 321, degree examination January 2012.
- Full Text: false
- Date Issued: 2012-01
Organic Chemistry 2: PAC 223
- Authors: Manene, N , Tichagwa, L
- Date: 2012-01
- Language: English
- Type: Examination paper
- Identifier: vital:17819 , http://hdl.handle.net/10353/d1010372
- Description: Organic Chemistry 2: PAC 223, supplementary examination January 2012
- Full Text: false
- Date Issued: 2012-01
Auditing 2B
- Authors: Emslie, Denny , Hanner, Lana
- Date: 2011-11
- Subjects: Auditing -- Examinations, questions, etc.
- Language: English
- Type: Examination paper
- Identifier: vital:17408 , http://hdl.handle.net/10353/d1009772
- Description: Auditing 2B, final assessment November 2011.
- Full Text:
- Date Issued: 2011-11
IsiXhosa Method: EDX 212
- Authors: Mdaka, V N , Tyilo, P N
- Date: 2011-11
- Language: English
- Type: Examination paper
- Identifier: vital:18396 , http://hdl.handle.net/10353/d1011557
- Description: IsiXhosa Method: EDX 212, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-11
Accounting: AFA 112
- Authors: Nobuya, X , Mnconywa, N
- Date: 2011-07
- Subjects: Accounting
- Language: English
- Type: Examination paper
- Identifier: vital:17415 , http://hdl.handle.net/10353/d1009781
- Description: Accounting: AFA 112, examination July 2011.
- Full Text: false
- Date Issued: 2011-07