Biological activities of plant extracts from Ficus elastica and Selaginella vogelli: an antimalarial, antitrypanosomal and cytotoxity evaluation
- Authors: Meyer, Franck , Isaacs, Michelle , Noundou, Xavier S , Krause, Rui W M , Teinkela, J E M , Hoppe, Heinrich C , Mpondo, Albert E M , Azebaze, Anatole G B , Nguemfo, Edwige L , Wintjens, Rene
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126142 , vital:35853 , https://doi.org/10.1016/j.sjbs.2017.07.002
- Description: The cytotoxic, antiplasmodial, and antitrypanosomal activities of two medicinal plants traditionally used in Cameroon were evaluated. Wood of Ficus elastica Roxb. ex Hornem. aerial roots (Moraceae) and Selaginella vogelii Spring (Selaginellaceae) leaves were collected from two different sites in Cameroon. In vitro cell-growth inhibition activities were assessed on methanol extract of plant materials against Plasmodium falciparum strain 3D7 and Trypanosoma brucei brucei, as well as against HeLa human cervical carcinoma cells. Criteria for activity were an IC50 value 10 μg/mL. The extract of S. vogelii did not significantly reduce the viability of P. falciparum at a concentration of 25 μg/mL but dramatically affected the trypanosome growth with an IC50 of 2.4 μg/mL. In contrast, at the same concentration, the extract of F. elastica exhibited plasmodiacidal activity (IC50 value of 9.5 μg/mL) and trypanocidal (IC50 value of 0.9 μg/mL) activity. Both extracts presented low cytotoxic effects on HeLa cancer cell line. These results indicate that the selected medicinal plants could be further investigated for identifying compounds that may be responsible for the observed activities and that may represent new leads in parasitical drug discovery.
- Full Text:
- Date Issued: 2018
Biological activity of plant extracts and isolated compounds from Alchornea laxiflora: Anti-HIV, antibacterial and cytotoxicity evaluation
- Authors: Ndinteh, Derek T , Olivier, D K , Noundou, Xavier S , Krause, Rui W M , Mnkandhla, D , Isaacs, Michelle , Hoppe, Heinrich C , Muganza, F M , Mbafor, J T , Van Vuuren, S F , Patnala, S
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126634 , vital:35907 , https://doi.org/10.1016/j.sajb.2018.08.010
- Description: This study was designed to assess the cytotoxicity, anti-HIV and antibacterial efficacy of various solvent extracts of roots, stem and leaves of Alchornea laxiflora, as well as five compounds isolated from its methanolic stem extract viz.; ellagic acid (1); 3-O-methyl-ellagic acid (2), 3-O-β-d-glucopyranosyl-β-sitosterol (3), 3-O-acetyl-oleanolic acid (4) and 3-O-acetyl-ursolic acid (5). The tested crude extracts were prepared from several solvent polarities including: hexane (Hex), chloroform (CHCl3), ethyl acetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O). The anti-HIV properties were assessed on HIV-1 subtype C integrase while the cytotoxicity was tested against Hela cells. The antibacterial activity was studied on a panel of pathogens including gastrointestinal, skin, respiratory and urinary-tract infection causing Gram positive bacteria viz.; Bacillus cereus (ATCC 11778), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25923) and Staphylococcus saprophyticus (ATCC 15305)] and Gram-negative bacteria, i.e., Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 13883), Moraxella catarrhalis (ATCC 23246). All the tested samples were determined to be non-toxic due to the low inhibitions observed. The most potent anti-HIV activity was observed for the methanolic extract of A. laxiflora root (ALR4) with an IC50 value of 0.21 ng/ml, which was more active than chicoric acid used as reference drug (6.82 nM). Roots, stem and leaves of A. laxiflora extracts exhibited antibacterial activities against most of the Gram-positive bacteria with the minimum inhibitory concentrations (MIC) ranging between 50 and 63 μg/ml. Compounds 1–5 displayed antibacterial activities against S. saprophyticus with MIC values as low as 4 μg/ml. The results inferred from this study demonstrate the potential of A. laxiflora root as a source for new anti-HIV drugs and scientifically validate the traditional use of A. laxiflora in the treatment of gastrointestinal, skin, respiratory and urinary tract related infections. These results reaffirm the ethnopharmacological significance of African traditional medicines.
- Full Text:
- Date Issued: 2018
Effectiveness of Sampling a Small Sized Network Telescope in Internet Background Radiation Data Collection
- Authors: Chindipha, Stones D , Irwin, Barry V W , Herbert, Alan
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427646 , vital:72453 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327624431_Effectiveness_of_Sampling_a_Small_Sized_Net-work_Telescope_in_Internet_Background_Radiation_Data_Collection/links/5b9a5067299bf14ad4d793a1/Effectiveness-of-Sampling-a-Small-Sized-Network-Telescope-in-Internet-Background-Radiation-Data-Collection.pdf
- Description: What is known today as the modern Internet has long relied on the existence of, and use of, IPv4 addresses. However, due to the rapid growth of the Internet of Things (IoT), and limited address space within IPv4, acquiring large IPv4 subnetworks is becoming increasingly difficult. The exhaustion of the IPv4 address space has made it near impossible for organizations to gain access to large blocks of IP space. This is of great concern particularly in the security space which often relies on acquiring large network blocks for performing a technique called Internet Background Radiation (IBR) monitoring. This technique monitors IPv4 addresses which have no services running on them. In practice, no traffic should ever arrive at such an IPv4 address, and so is marked as an anomaly, and thus recorded and analyzed. This research aims to address the problem brought forth by IPv4 address space exhaustion in relation to IBR monitoring. This study’s intent is to identify the smallest subnet that best represents the attributes found in the/24 IPv4 address. This is done by determining how well a subset of the monitored original subnetwork represents the information gathered by the original subnetwork. Determining the best method of selecting a subset of IPv4 addresses from a subnetwork will enable IBR research to continue in the best way possible in an ever restricting research space.
- Full Text:
- Date Issued: 2018
Establishment of “The South African Bioinformatics Student Council” and activity highlights:
- Authors: Rafael, Candice Nancy , Ambler, Jon , Niehaus, Antoinette , Ross, James , Tastan Bishop, Özlem
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148250 , vital:38723 , https://doi.org/10.14806/ej.23.0.903
- Description: The South African Society for Bioinformatics1 (SASBi) was officially formed in September 2012 during a joint Congress with the South African Genetics Society (SAGS). Prior to this there was no official body to represent bioinformatic researchers and students in the country. The establishment of SASBi also led to the establishment of the Student Society as a platform for students to meet and discuss their research activities, but also to socialise and broaden their network of knowledge and friendships. A small group of students joined as volunteers to pioneer and set up a SASBi Student Council (SASBiSC). As a first step, one representative, selected from the attendees present at the first Joint Congress of SASBi and SAGS, was elected to the main SASBi Council.
- Full Text:
- Date Issued: 2018
Hybrid Sensor Simulation within an ICS Testbed
- Authors: Shaw, Brent , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427713 , vital:72457 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327624204_Hybrid_Sensor_Simulation_within_an_ICS_Testbed/links/5b9a50d8299bf14ad4d79587/Hybrid-Sensor-Simulation-within-an-ICS-Testbed.pdf
- Description: Industrial Control Systems (ICS) are responsible for managing factories, power-grids and water treatment facilities, and play a key role in running and controlling national Critical Information Infrastructure (CII). The integrity and availability of these systems are paramount, and the threat of cyberphysical attacks on these systems warrant thorough research into ensuring their security. The increasing interconnectivity seen in both the domestic and industrial sectors exposes numerous devices and systems to the Internet. These devices are exposed to malware and advanced persistent threats, that can affect CII through the attack of ICS. While simulations provide insights into how systems might react to certain changes, they generally lack the ability to be integrated into existing hardware systems. Hybrid testbeds could provide a platform for testing hardware and software components, enabling researchers to examine the interactions between various different networking through exploratory research and investigation in a controlled environment. This work presents an approach to traffic generation for use within ICS/IoT testbeds, through the production of Docker-based simulation nodes that are constructed based on the configuration of the system.
- Full Text:
- Date Issued: 2018
Offline-First Design for Fault Tolerant Applications.
- Authors: Linklater, Gregory , Marais, Craig , Herbert, Alan , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427683 , vital:72455 , https://www.researchgate.net/profile/Barry-Irwin/publication/327624337_Offline-First_Design_for_Fault_Tolerant_Applications/links/5b9a50a1458515310584ebbe/Offline-First-Design-for-Fault-Tolerant-Applications.pdf
- Description: Faults are inevitable and frustrating, as we increasingly depend on network access and the chain of services that provides it, we suffer a greater loss in productivity when any of those services fail and service delivery is suspended. This research explores connectivity and infrastructure fault tolerance through offline-first application design using techniques such as CQRS and event sourcing. To apply these techniques, this research details the design, and implementation of LOYALTY TRACKER; an offline-first, PoS system for the Android platform that was built to operate in the context of a small pub where faults are commonplace. The application demonstrates data consistency and integrity and a complete feature set that continues to operate while offline but is limited by scalability. The application successfully achieves it’s goals in the limited capacity for which it was designed.
- Full Text:
- Date Issued: 2018
Real-time geotagging and filtering of network data using a heterogeneous NPU-CPU architecture
- Authors: Pennefather, Sean , Bradshaw, Karen L , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427726 , vital:72458 , https://www.researchgate.net/profile/Barry-Irwin/publication/327630459_Real-Time_Geotagging_and_Filtering_of_Network_Data_using_a_Heterogeneous_NPU-CPU_Architecture/links/5b9a69d145851574f7c3d3b7/Real-Time-Geotagging-and-Filtering-of-Network-Data-using-a-Heterogeneous-NPU-CPU-Architecture.pdf
- Description: In this paper, we present the design and implementation of a NPU-CPU heterogeneous network monitoring application. This application allows for both filtering and monitoring operations to be performed on network traffic based on country of origin or destination of IP traffic in real-time at wire speeds up to 1 Gbit/s. This is achievable by distributing the application components to the relevant candidate architectures, leveraging the strengths of each. Communication between architectures is handled at runtime by a low latency synchronous message passing library. Testing of the implemented application indicates that the system can perform geolocation lookups on network traffic in real-time without impacting network throughput.
- Full Text:
- Date Issued: 2018
Spermatophore dimorphism in the chokka squid Loligo reynaudii associated with alternative mating tactics
- Authors: Sato, Noriyosi , Iwata, Yoko , Shaw, Paul W , Sauer, Warwick H H
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127070 , vital:35952 , https://doi.10.1093/mollus/eyy002
- Description: Chokka squid (Loligo reynaudii) have characteristic alternative mating tactics: ‘consort’ males temporarily pair with and guard a female and transfer spermatophores onto her oviduct opening inside the mantle cavity, whereas ‘sneaker’ males rush towards a mating pair and transfer spermatophores onto the female’s buccal membrane near her sperm storage organ. Differences in mating behaviours and their related sperm-storage sites clearly constrain the fertilization process and can drive dimorphism between consort and sneaker males. The presence and character of male dimorphism has not yet been fully examined in this species, but consort males are commonly much larger than sneaker males. We observed clear dimorphism in spermatangia (the sperm mass ejaculated from the spermatophore), consistently associated with the two alternative sperm storage sites on the female’s body. Observations of spermatophores stored in the Needham’s sac of mature males confirmed that small males produce ‘sneaker-type’ spermatangia whereas larger males produce ‘consort-type’ spermatangia, and no individuals possessed both types. Therefore, by association, the mating tactic adopted (including the sperm deposition site used) by individual males can be determined from observation of their spermatangial type, without requiring direct behavioural observation of mating. This ability to infer information about mating tactic will improve our understanding of the reproductive system and mating dynamics in this species.
- Full Text:
- Date Issued: 2018
Towards Enhanced Threat Intelligence Through NetFlow Distillation
- Authors: Herbert, Alan , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427699 , vital:72456 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327624198_Towards_Enhanced_Threat_Intelligence_Through_NetFlow_Distillation/links/5b9a501fa6fdcc59bf8ee8ea/Towards-Enhanced-Threat-Intelligence-Through-NetFlow-Distillation.pdf
- Description: Bolvedere is a hardware-accelerated NetFlow analysis platform intended to discern and distribute NetFlow records in a requested format by a user. This functionality removes the need for a user to deal with the NetFlow protocol directly, and also reduces the requirement of CPU resources as data would be passed on to a host in the known requested format.
- Full Text:
- Date Issued: 2018
Violations of good security practices in graphical passwords schemes: Enterprise constraints on scheme-design
- Authors: Vorster, Johannes , Irwin, Barry V W , van Heerden, Renier P
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430324 , vital:72683 , https://researchspace.csir.co.za/dspace/bitstream/handle/10204/10919/Vorster_22337_2018.pdf?sequence=1isAllowed=y
- Description: During the past decade, the sophistication and maturity of Enterprise-level Information Security (EIS) Standards and Systems has increased significantly. This maturity, particularly in the handling of enterprise-wide capability models, has led to a set of standards – e.g. ISO/IEC 27001, NIST 800-53, ISO/IEC 27789 and CSA CCM – that propose controls applicable to the implementation of an Information Security Manage-ment System (ISMS). By nature, the academic community is fruitful in its endeavour to propose new password schemes; and Graphical Passwords (GPs) have had many proposals for schemes. In this paper, we explore the impact of good security standards and lessons-learnt over the past decade of EID as a model of constraint on GPs schemes. The paper focuses on a number of GP schemes and points out the var-ious security constraints and limitations, if such schemes are to be im-plemented at the enterprise level.
- Full Text:
- Date Issued: 2018
Calcium supplementation commencing before or early in pregnancy, or food fortification with calcium, for preventing hypertensive disorders of pregnancy
- Authors: Hofmeyr, Georges Justus , Manyame, S
- Date: 2017
- Subjects: South Africa Pregnancy Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6215 , vital:45282 , "https://DOI:10.1002/14651858.CD011192.pub2"
- Description: Background Pre-eclampsia is considerably more prevalent in low- than high-income countries. One possible explanation for this discrepancy is dietary diKerences, particularly calcium deficiency. Calcium supplementation in the second half of pregnancy reduces the serious consequences of pre-eclampsia and is recommended by the WorldHealthOrganization (WHO) for women with low dietary calcium intake, but has limited eKect on the overallrisk of pre-eclampsia. It is important to establish whether calcium supplementation before and in early pregnancy has added benefit. Such evidence would be justification for population-level fortification of staple foods with calcium. Objectives To determine the eKect of calcium supplementation or food fortification with calcium, commenced before or early in pregnancy and continued at least until mid-pregnancy, on pre-eclampsia and other hypertensive disorders, maternal morbidity and mortality, as well as fetal and neonatal outcomes. Search methods We searched the Cochrane Pregnancy and Childbirth Trials Register (10 August 2017), PubMed (29 June 2017), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (10 August 2017) and reference lists of retrieved studies. Selection criteria Randomised controlled trials of calcium supplementation orfood fortification which include women of child bearing age not yet pregnant, or in early pregnancy. Cluster-RCTs, quasi-RCTs and trials published in abstract form only would have been eligible for inclusion in this review but none were identified. Cross-over designs are not appropriate for this intervention. The scope of this review is to consider interventions including calcium supplementation with or without additional supplements or treatments, compared with placebo or no intervention. Data collection and analysis Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Main results This review is based on one RCT (involving 60 women) which looked at calcium plus additional supplements versus control. The women (who had lowantioxidant status)were in the early stages of pregnancy.We did notidentify any studieswhere supplementation commenced pre-pregnancy. Another RCT comparing calcium versus placebo is ongoing but not yet complete. We did not identify any studies looking at any of our other planned comparisons. Calcium plus antioxidants and other supplements versus placebo We included one small study (involving 60 women with low antioxidantlevels) which was conducted in an academic hospital in Indondesia. The study was at low risk of bias for all domains with the exception of selective reporting, for which it was unclear. Women in the intervention group received calcium (800 mg) plus N-acetylcysteine (200 mg), Cu (2 mg), Zn (15 mg), Mn (0.5 mg) and selenium (100 mcg) and vitamins A (1000 IU), B6 (2.2 mg), B12 (2.2 mcg), C (200 mg), and E (400 IU) versus the placebo control group of women who received similar looking tablets containing iron and folic acid. Both groups received iron (30 mg) and folic acid (400 mcg). Tablets were taken twice daily from eight to 12 weeks of gestation and then throughout pregnancy. The included study found that calcium supplementation plus antioxidants and other supplements may slightly reduce pre-eclampsia (gestational hypertension and proteinuria) (risk ratio (RR) 0.24, 95% confidence interval (CI) 0.06 to 1.01; low-quality evidence), but this is uncertain due to wide confidence intervals just crossing the line of no eKect, and small sample size. It appears that earlypregnancy loss before 20 weeks' gestation (RR 0.06, 95% CI 0.00 to 1.04; moderate-quality evidence) may be slightly reduced by calcium plus antioxidants and other supplements, but this outcome also has wide confidence intervals, which just cross the line of no eKect. Very few events were reported under the composite outcome, severe maternal morbidity and mortality index and no clear diKerence was seen between groups (RR 0.36, 95% CI 0.04 to 3.23; low-quality evidence). However, the included study observed a reduction in the composite outcome pre-eclampsia and/or pregnancy loss at any gestational age (RR 0.13, 95% CI 0.03 to 0.50; moderate-quality evidence), and pregnancy loss/stillbirth at any gestational age (RR 0.06, 95% CI 0.00 to 0.92;moderate-quality evidence)in the calcium plus antioxidant/supplement group. Other outcomes reported (placental abruption, severe pre-eclampsia and preterm birth (less than 37 weeks' gestation)) were too infrequent for meaningful analysis. No data were reported for the outcomes caesarean section, birthweight less 2500 g, Apgar score less than seven at five minutes, death or admission to neonatal intensive care unit (ICU), or pregnancy loss, stillbirth or neonatal death before discharge from hospital. Authors' conclusions The results of this review are based on one small study in which the calcium intervention group also received antioxidants and other supplements. Therefore, we are uncertain whether any of the eKects observed in the study were due to calcium supplementation or not. The evidence in this review was graded low to moderate due to imprecision. There is insuKicient evidence on the eKectiveness or otherwise of pre- or early-pregnancy calcium supplementation, or food fortification for preventing hypertensive disorders of pregnancy. Furtherresearch is needed to determine whether pre- or early-pregnancy supplementation, orfood fortification with calcium is associated with a reduction in adverse pregnancy outcomes such as pre-eclampsia and pregnancy loss. Such studies should be adequately powered, limited to calcium supplementation, placebo-controlled, and include relevant outcomes such as those chosen for this review. There is one ongoing study of calcium supplementation alone versus placebo and this may provide additional evidence in future updates
- Full Text:
- Date Issued: 2017
Investigating the utilization of the secure hash algorithm to generate electromagnetic noise
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430222 , vital:72674 , https://doi.org/10.1145/3163080.3163089
- Description: This research introduces an electromagnetic (EM) noise generator known as the FRIES noise generator to mitigate and obfuscate Side Channel Analysis (SCA) attacks against a Raspberry Pi. The FRIES noise generator utilizes the implementation of the Secure Hash Algorithm (SHA) from OpenSSL to generate white noise within the EM spectrum. This research further contributes to the body of knowledge by demonstrating that the SHA implementation of libcrypto++ and OpenSSL had different EM signatures. It was further revealed that as a more secure implementation of the SHA was executed additional data lines were used, resulting in increased EM emissions. It was demonstrated that the OpenSSL implementations of the SHA was more optimized as opposed to the libcrypto++ implementation by utilizing less resources and not leaving the device in a bottleneck. The FRIES daemon added noise to the EM leakage which prevents the visual location of the AES-128 cryptographic implementation. Finally, the cross-correlation test demonstrated that the EM features of the AES-128 algorithm was not detected within the FRIES noise.
- Full Text:
- Date Issued: 2017
Isolation, identification and genetic characterisation of a microsporidium isolated from carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae)
- Authors: Lloyd, Melissa , Knox, Caroline M , Hill, Martin P , Moore, Sean D
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59874 , vital:27674 , https://doi.org/10.4001/003.025.0529
- Description: 'Microsporidia' is a term used for organisms belonging to the phylum Microspora, which contains approximately 187 genera and 1500 species (Corradi 2015). They are obligate intracellular parasites with no active metabolic stages of the life cycle occurring outside of the host cells (Franzen & Muller 1999; Garcia 2002; Tsai et al. 2003; Huang et al. 2004). They exhibit eukaryotic characteristics such as a membrane-bound nucleus, an intracytoplasmic membrane system, and chromosome separation occurs on mitotic spindles. However, they also exhibit prokaryotic characteristics such as possession of a 70S ribosome, lack of true mitochondria and peroxisomes, a simple version of the Golgi apparatus, and a small genome which is much less complex than those of most eukaryotes (Franzen & Muller 1999; Garcia 2002). Microspo- ridia are parasitic in all major groups of animals, both vertebrates and invertebrates (Sprague 1977; Franzen & Muller 1999). Microsporidia were first recognised as pathogens in silkworms by Nageli (1857), and now have been found to infect many hosts such as humans, insects, fish and mammals (Stentiford et al. 2016).
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- Date Issued: 2017
Roundtable review: cold case: the elusive story of Julie Ward's murder
- Authors: Spencer, Lynda G
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/138894 , vital:37683 , https://doi.org/10.1080/23277408.2017.1362199
- Description: A Death Retold in Truth and Rumour: Kenya, Britain and the Julie Ward Murder by Grace Ahingila Musila is an extraordinary, captivating, thought-provoking and chilling account of the unsolved murder of Julie Ward. Musila points out that this book does not set out to reveal who murdered Julie Ward. Instead, as an academic, she is interested in examining the intertextual process between the rumours around this cold case and the evidence available in various published accounts, such as books, newspapers and court judgements.
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- Date Issued: 2017
Street trees contribute to urban sustainability in South African towns
- Authors: Shackleton, Charlie M , Gwedla, Nanamhla
- Date: 2017
- Subjects: City planning -- Environmental aspects Sustainable urban development Community development -- Environmental aspects -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/54269 , vital:26440
- Description: Urban green spaces and trees are increasingly recognised as crucial elements in the quest for urban sustainability internationally, and for the promotion of urban liveability and quality of life in cities. So much so that many countries now have guidelines or regulations regarding either the amount of urban greenery that must be provided per capita, or the maximum distance that any dwelling can be from green spaces of stipulated sizes. For example, the European Union recently more than doubled its recommendation of 9 m2 of public green per person to 20 m2 per person.
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- Date Issued: 2017
A Geopolitics of knowledge and the value of discomfort:
- Authors: Simbao, Ruth K
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146444 , vital:38526 , https://www.ru.ac.za/fineart/latestnews/alutacontinuadoingitfordaddytenyearson.html
- Description: In 2006, the short essay ‘Doing it for Daddy’ by visual artist Sharlene Khan caused controversy when it expressed the opinion that since 1994, ‘transformation’ in the visual arts field in South Africa seemed to have halted at the point of White women replacing White men in positions of power. It questioned this new position of dominance in institutions that remained colonially and racially untransformed. On the 16 and 17th of September 2016, the School of Fine Art at Rhodes University will host a one-day symposium ‘A luta Continua: Doing it for Daddy - Ten years on…’ which seeks to both commemorate that article and those who ‘speak up’, but also, fundamentally, to continue looking at the ways in which various social oppressions intersect in the fields of art history and visual arts in South Africa. Presenters include Khwezi Gule, Nontobeko Ntombela, Nomusa Makhubu, Same Mdluli, Fouad Asfour, Ruth Simbao, Sharlene Khan, students from Wits School of Arts and Rhodes Art History and Visual Culture, as well as a performance by visual artist Sikhumbuzo Makandula.
- Full Text:
- Date Issued: 2016
A multi-threading approach to secure VERIFYPIN
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429244 , vital:72570 , https://ieeexplore.ieee.org/abstract/document/7802952
- Description: This research investigates the use of a multi-threaded framework as a software countermeasure mechanism to prevent attacks on the verifypin process in a pin-acceptance program. The implementation comprises of using various mathematical operations along side a pin-acceptance program in a multi-threaded environment. These threads are inserted randomly on each execution of the program to create confusion for the attacker. Moreover, the research proposes a more improved version of the pin-acceptance program by segmenting the pro-gram. The conventional approach is to check each character one at a time. This research takes the verifying process and separates each character check into its individual thread. Furthermore, the order of each verified thread is randomised. This further assists in the obfuscation of the process where the system checks for a correct character. Finally, the research demonstrates it is able to be more secure than the conventional countermeasures of random time delays and insertion of dummy code.
- Full Text:
- Date Issued: 2016
Improving Fidelity in Internet Simulation through Packet Injection
- Authors: Koorn, Craig , Irwin, Barry V W , Herbert, Alan
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427786 , vital:72462 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622877_Improving_Fidelity_in_Internet_Simulation_through_Packet_Injection/links/5b9a1a47458515310583fd8a/Improving-Fidelity-in-Internet-Simulation-through-Packet-Injection.pdf
- Description: This paper describes the of extension implemented to the NKM Internet simulation system, which allows for the improved of injection of packet traffic at arbitrary nodes, and the replay of previously recorded streams. The latter function allows for the relatively easy implementation of Internet Background Radiation (IBR) within the simulated portion of the Internet. This feature thereby enhances the degree of realism of the simulation, and allows for certain pre-determined traffic, such as scanning activity, to be injected and observed by client systems connected to the simulator.
- Full Text:
- Date Issued: 2016
New evidence for the correlation of basalts of the Suurberg Group with the upper part of the Karoo basalt sequence of Lesotho:
- Authors: Marsh, J S Goonie
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/145122 , vital:38410 , ISBN 9783319408590 , https://link.springer.com/chapter/10.1007/978-3-319-40859-0_6
- Description: Tholeiitic basalts build the Mimosa Formation, the uppermost stratigraphic unit of the Suurberg Group in the northern part of the Algoa Basin. Exposures are very poor and the tectonic significance of the Suurberg rocks and the origin of the Mimosa basalts are contentious. Drilling of stratigraphic boreholes at four localities allowed detailed sampling of the basalts from two cores 90 km apart for geochemical, age and palaeomagnetic investigations.
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- Date Issued: 2016
Spotlight on the Art of Darkness: The Kin Artstudio
- Authors: Tshilumba Mukendi, J S
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146434 , vital:38525 , https://artafricamagazine.org/magazine-archive/?v=e4dd286dc7d7
- Description: Issue December 2016. What Really Matters.
- Full Text:
- Date Issued: 2016