Curiosity first, applications later
- Authors: Berold, Robert , Limson, Janice L
- Date: 2009
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7188 , http://hdl.handle.net/10962/d1006281 , http://www.sajs.co.za/sites/default/files/publications/pdf/1-4-1-PB.pdf , Nyokong, Tebello
- Description: Tebello Nyokong speaks to Robert Berold and Janice Limson about her career as a chemist. Tebello Nyokong, who holds a research chair in medicinal chemistry and nanotechnology at Rhodes University, has become the first South African scientist to win the L’Oreal-UNESCO award for women in science, in the physical sciences. Only one laureate is selected from each of five world regions, and Nyokong is the 2009 laureate for Africa and the Arab states. She and the winners from the other four regions travel to Paris in March to each accept the award and a generous prize of close to R1 million. Nyokong now heads the new Nanotechnology Innovation Centre for medical sensors: the biggest single research investment in the history of Rhodes. Linked to other nanotechnology centres in the country, it is designed to bridge the gap between research and the market.
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- Date Issued: 2009
Will the real custodian of natural resource management please stand up
- Authors: Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6657 , http://hdl.handle.net/10962/d1007076
- Description: South Africa is the custodian of an immense wealth of biodiversity resources, and is estimated to be the third most biodiverse country in the world. At the ecosystem level this biodiversity supports the production of goods and services used by us all; water, air, soil fertility, wood, food, etc. At a more local level the harvesting of numerous natural resources provides consumptive products for millions of poor South Africans, as well as income for equally significant numbers.Consumption of and trade in these resources is the very mainstay of their well-being, and crucial in preventing deeper poverty levels. For example, despite massive improvements in the provision of electricity, most rural and a significant proportion of urban South Africans continue to use fuelwood as a key energy source for cooking (e.g. 65% of electrified households in the urban areas of Makana municipality, and 92% of households in the rural areas of Bushbuckridge); approximately 75% of the population use medicinal plants for medicinal or cultural reasons; and millions of urban and rural households make use of wild edible herbs. With such high demand for these resources, it is not unsurprising that there are large and established trade networks spanning local, regional, national and, for some resources (e.g. specific medicinal plants, mopane worms), international boundaries. The total value of this trade is unknown, and unrecorded in local or national economic or GDP statistics. It certainly equates to billions of rands per year. The direct-use and trade values are substantial and provide a cost saving to the State. Where biodiversity resources are overused or exhausted, people have to purchase alternatives, which reduces their scarce cash resources, thereby increasing their likely dependency on State welfare grants.
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- Date Issued: 2009
Pseudopolydora species associated with mollusc shells on the south coast of South Africa, with the description of Ps. dayii, sp nov
- Authors: Simon, Carol A
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6875 , http://hdl.handle.net/10962/d1011623
- Description: Two species of the genus Pseudopolydora, Ps. dayii, sp. nov. and Ps. antennata, were associated with gastropods on the south and south-east coasts of South Africa. Pseudopolydora dayii is characterized by prominent post-chaetal notopodial lobes on chaetiger 1 with very long chaetae, a prominent occipital tentacle, having hooded hooks that start on chaetiger 9, branchiae that start on chaetiger 6, stout hooks and lobes placed latero-posteriorly to the hooded hooks in posterior chaetigers. It is a surface-fouler and was found on several species of wild gastropods at four of the five sites sampled and from additional material from the south-west coast and on cultured abalone (Haliotis midae) at a farm on the south-west coast. Three individuals of Ps. antennata were found only with oysters at the easternmost site. This was the first record of this species outside of the Western Cape Province and it is possible that their association with the oysters was fortuitous.
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- Date Issued: 2009
Obesity: a preliminary report of an introductory service-learning course on the role of pharmacy students in health promotion
- Authors: Srinivas, Sunitha C , Wrench, Wendy W , Karekazi, Catherine W , Radloff, Sarah E , Daya, Santylal
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6454 , http://hdl.handle.net/10962/d1006833
- Description: Lifestyle diseases such as obesity have been neglected in developing countries partly due to a more urgent focus on infectious diseases in these countries. The incidence of obesity is on the increase in developing countries, with a marked rise in childhood obesity. A health promotioning service-learning principles required final year pharmacy students to prepare a pilot-tested computer-based quiz, using a pre- and post-intervention test design, along with other learning material, for participants at the 2007 Sasol National Festival of Science and Technology (SciFest). Interactive models, posters and information leaflets were used in explaining the prevention and control of obesity to learners. The results showed that the pre-existing knowledge of the participants was good. There was a further improvement after the educational intervention. Activities such as this are important in heightening awareness of obesity in learners as it is likely to reduce the incidence of obesity later in life. Furthermore, the activity also served to increase awareness of the role of pharmacists in the prevention of lifestyle diseases such as obesity.
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- Date Issued: 2009
Fluorescence studies of quantum dots and zinc tetraamino phthalocyanine conjugates
- Authors: Britton, Jonathan , Antunes, Edith M , Nyokong, Tebello
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6565 , http://hdl.handle.net/10962/d1004124
- Description: CdTe Qds capped with mercapto propionic acid (MPA) were covalently linked to zinc tetraamino phthalocyanine (ZnTAPc) using N-ethyl-N(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxy succinimide (NHS) as the coupling agents. The results presented give evidence in favour of the formation of an amide bond between ZnTAPc and CdTe QDs. Both the linked ZnTAPc–QD complexes and a mixture of QDs and ZnTAPc (i.e. without chemical linking) showed Förster resonance energy transfer (FRET). ZnTAPc quenched the QDs emission, giving quenching constants in the order of 103 M−1.
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- Date Issued: 2009
The evaluation of Eudragit microcapsules manufactured by solvent evaporation using USP Apparatus 1
- Authors: Khamanga, Sandile M , Parfitt, Natalie R , Nyamuzhiwa, Tsitsi , Haidula, Hendrina , Walker, Roderick B
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6389 , http://hdl.handle.net/10962/d1006310
- Description: The objectives of this study were to prepare microcapsules containing verapamil and propranolol and to evaluate the kinetics and mechanism of drug release from the microcapsules using USP Apparatus 1. The effects of polymer concentration and polymer type on the cumulative amount of drug released were evaluated. The microcapsules were manufactured using Eudragit RS and RL polymers by solvent evaporation with the ultimate aim of prolonging drug release. Twenty-four formulations were prepared using different drug/polymer ratios. The effects of polymer type and polymer/drug ratios on the size, flow properties, surface morphology, and the release characteristics of the microcapsules were examined. The effects of drug inclusion methods on drug loading, encapsulation efficiency, and release properties of the complex microcapsules were also investigated. The formulations containing drug/polymer ratio 1:4 (w/w) were the most appropriate with respect to encapsulation efficiency (70%), flow properties (HR = 1.2), drug loading (15–20%), and drug release characteristics, in all cases. The release kinetics from the different formulations followed mainly a diffusion-controlled mechanism.
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- Date Issued: 2009
Efficacy of solar power units for small-scale businesses in a remote rural area, South Africa
- Authors: Hajat, A , Banks, D , Aiken, R , Shackleton, Charlie M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6636 , http://hdl.handle.net/10962/d1006860
- Description: Much work has considered the practicalities and affordability of solar systems for domestic energy supplies in remote rural areas. There is less understanding of its utility for small-scale business enterprises in such areas. We examined the patterns of use of two 12 V and one 24 V systems for small-scale enterprises housed in transportable containers. Monitoring of load shed and top of charge indicated that the 12 V systems were inadequate to meet the requirements of the enterprises. The 24 V operation performed a lot better. Despite some technical limitations the system offered a number of social, economic and environmental positives; primarily the offering of business products not otherwise available in the area, incomes to the entrepreneurs and greater connectivity with regional centres through office services such as cell-phone charging and faxing. Customers of the small-scale enterprises felt that their presence in the area saved them some money because they no longer had to travel as frequently to regional urban centres.
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- Date Issued: 2009
Jimmy Riadore: organ-builder, bell-ringer and hanger of the bells at St George's Cathedral, Cape Town
- Authors: Lewis, Colin A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6190 , http://hdl.handle.net/10962/d1012396
- Description: Born in Lewes, Sussex, Jimmy Riadore came to South Africa in 1958. Organs, bells and clocks have been the focus of his life, and he has tuned, built, repaired and restored them all over southern Africa. Recently he has extended his careful ministrations to St Helena. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
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- Date Issued: 2009
A change of the seaward boundary of Goukamma Marine Protected Area could increase conservation and fishery benefits
- Authors: Gotz, A , Kerwath, S E , Attwood, Colin G
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:7147 , http://hdl.handle.net/10962/d1011846 , https://doi.org/10.4102/sajs.v105i9/10.102
- Description: Goukamma Marine Protected Area (MPA) on the South African temperate South Coast has been shown to be effective in maintaining a spawning stock of roman, Chrysoblephus laticeps (Sparidae). The larval ecology and the oceanographic conditions in the area suggest a good potential for the enhancement of roman stocks outside the reserve through larval dispersal. A high rate of illegal fishing just inside the seaward boundary of the MPA could severely compromise its function.We suggest that a change of the seaward boundary of the reserve to coincide with a latitudinal line could increase its function as a harvest refuge for resident reef fishes such as roman, facilitate voluntary compliance and monitoring and prosecution of illegal fishing without a significant negative impact on the commercial linefishing fleet in the area. Simple adjustments such as the one proposed here could be attempted at a number of South African MPAs as they would be beneficial to achieve fishery and conservation goals alike.
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- Date Issued: 2009
Hold the prawns
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6206 , http://hdl.handle.net/10962/d1008576
- Description: [From introduction]: In the cities of the global South elites are often desperate to repress the reality of the shack settlement. Maps are printed in which shack settlements appear as blank spaces, laws are passed that assume that everyone can afford to live formally and, in the name of order and development, the poor are beaten out of the cities. The great elite fantasy is the creation of 'world class cities' – shiny, securitised nowherevilles in which the poor understand that their place is to live in some peripheral ghetto and only come into the city as menial workers. But from City of God to Slum Dog Millionaire and now District 9 cinema has put the shack settlement in the mall and at the heart of how Rio, Bombay and Johannesburg feature in the global imagination.
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- Date Issued: 2009
Land occupation and the limits of party politics
- Authors: Pithouse, Richard, 1970-
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6200 , http://hdl.handle.net/10962/d1008565
- Description: In the recent election the DA, together with COPE, made much of their intention to defend the rule of the law. But while the dust thrown up in that election is still settling, the City of Cape Town is already engaged in violent and unlawful behaviour towards its most vulnerable citizens.
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- Date Issued: 2009
Hydrology, sediment transport dynamics and geomorphology of a variable flow river : the Mfolozi River, South Africa
- Authors: Grenfell, Suzanne E , Ellery, William F N
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6632 , http://hdl.handle.net/10962/d1006826
- Description: The co-efficient of variation for inter-annual streamflow of the Mfolozi River is extremely high at 79%. An analysis of flow frequency indicated that streamflow is skewed towards low-flow values, with a number of extremely large flood events occurring as outliers on the histogram. Streamflow variability in the Mfolozi River may be linked to multiple factors including a large catchment size, a seasonal climate of a dry winter and wet summer, evergreen vegetation in the catchment, variable precipitation and the occurrence of regionally pervasive climatic oscillations. This research aimed to address how streamflow variability impacted upon sediment transport and thus, geomorphology. It was found that sediment transport variability occurred at the intra-and inter-annual scale. Analysis of mean monthly sediment concentration and discharge showed a hysteresis effect, such that sediment concentration peaked prior to discharge in the early wet season. During the late wet season, peak discharges often had unexpectedly low sediment concentrations. Furthermore, data suggested the existence of long-term hysteresis that may be related to decadal-scale climatic oscillations that alter sediment availability and stream capacity, resulting in discharge peaking in 2000 and sediment concentration in 2005. However, more data are required to confirm this relationship. Variability in streamflow appears to share a causal relationship with sediment transport variability, as both are linked to variation in precipitation and the resultant impacts on vegetation growth and evapotranspiration rates. The variability of streamflow and sediment transport has implications for stream and floodplain geomorphology, and the hydrology of variable rivers should be considered when interpreting their geomorphology.
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- Date Issued: 2009
Taking education and training to higher levels
- Authors: Phiri, Aretha
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:7203 , http://hdl.handle.net/10962/d1006400
- Description: Professor Tebello Nyokong of the Chemistry Department has won yet another prestigious award. She was voted "the most influential women in business and government" in the category of education and training, in an event sponsored by CEO Magazine.
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- Date Issued: 2009
Dedication of Jo'burg's new ring
- Authors: Lewis, Colin A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6189 , http://hdl.handle.net/10962/d1012395 , http://www.ringingworld.co.uk
- Description: Five years of planning, fund raising and hard work came to fruition in November 2008 when Africa's newest ring of bells was dedicated, bringing the first part of the Jo'burg Project to a successful conclusion.
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- Date Issued: 2009
Seeing is natural, but viewing is not: teaching visual literacy in a rural classroom
- Authors: Mbelani, Madeyandile , Murray, Sarah
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6108 , http://hdl.handle.net/10962/d1009738
- Description: This paper reports on a collaborative action research case study into Grade 10 teaching and learning of visual literacy in a rural high school into the Eastern Cape, South Africa. Visual literacy is a new aspect that has been incorporated in English First Additional Language National Curriculum Statement (Grade 10-12), which has been implemented in Grade 10 from 2006. With the aim of gaining knowledge and improving performance in visual literacy, I designed a unit of lessons, which exposed learners to visual grammar and visual texts and I collected data around the implementation of the lesson unit as evidenced by journal writing, interviews and non-participant observation. The data revealed that visual literacy could be taught meaningfully in a rural high school as the learners could identify, cut, paste and critically discuss elements of visual language and they finally designed their own advertisements in groups. However, the following factors emerged as hindrances to the successful teaching of visual literacy in this case: lack of resources; learners' lack of a foundation in visual literacy from Grades 7-9; and problems revolving around time management and pacing.
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- Date Issued: 2009
Drawing Lines in the Sand: AM v RM 2010 2 SA 223 (ECP)
- Authors: Kruuse, Helen
- Date: 2009
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54107 , vital:26391 , http://www.ufh.ac.za/speculumjuris/files/pdf/SpeculumJuris_2009_Part_2.pdf
- Description: Judge Elna Revelas’s decision in the case of Mohamed v Mohamed 1 may be described as one of those run-of-the-mill applications in terms of rule 43 which are routinely heard on motion court days in any one of our high courts across the country. This case note suggests that her decision belies such a description. Instead, this note suggests that her decision marks a move away from existing jurisprudence on Muslim marriages in a way which may undermine, rather than promote, the recognition and respect for the marriage institutions of different religious systems and beliefs. I tentatively suggest that by granting the rule 43 application the court may have effectively imposed civil marriage obligations on a religious marriage even though the parties had not concluded a marriage in terms of the Marriage Act.2 As such, the decision has potentially radical consequences for parties in Muslim marriages and highlights the complex issues that courts have had to face in the last two decades without any guiding legislation. In order to understand the judgment properly, its context has to be considered. This context includes (1) the numerous judgments extending protection to women in Muslim marriages in the last two decades against the backdrop of the coming into effect of the Constitution of the Republic of South Africa, 1996; and (2) the application by the Women’s Legal Centre Trust (hereafter “WLCT”) to the Constitutional Court to force the President and Parliament to enact legislation to recognise and protect Muslim marriages.
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- Date Issued: 2009
Stronger induction of callose deposition in barley by Russian wheat aphid than bird cherry-oat aphid is not associated with differences in callose synthase or ≤-1,3-glucanase expression
- Authors: Saheed, Sefiu A , Cierlik, Izabela , Larsson, Kristina A E , Delp, Gabriele , Bradley, Graeme , Jonsson, Lisbeth M V , Botha, Christiaan E J
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6542 , http://hdl.handle.net/10962/d1005984
- Description: The effects of infestation by the bird cherry-oat aphid (BCA), (Rhopalosiphum padi L) and the Russian wheat aphid (RWA) (Diuraphis noxia Mordvilko) on callose deposition and gene expression related to callose accumulation were investigated in barley (Hordeum vulgare L. cv. Clipper). The BCA, which gives no visible symptoms, induced very limited callose deposition, even after 14 days of infestation. In contrast, RWA, which causes chlorosis, white and yellow streaking and leaf rolling, induced callose accumulation already after 24h in longitudinal leaf veins. The deposition was pronounced after 72 h, progressing during 7 and 14 days of infestation. In RWA-infested source leaves, callose was also induced in longitudinal veins basipetal to the aphid-infested tissue, whereas in sink leaves, more callose deposition was found above the feeding sites. Nine putative callose synthase genes were identified in a data base search, of which eight were expressed in the leaves, but with similar level of expression in control and aphid-infested tissue. Four out of 12 examined β-1,3-glucanases were expressed in the leaves, and three of them were up-regulated in aphid-infested tissue. They were all more strongly induced by RWA than BCA. The results suggest that callose accumulation may be partly responsible for the symptoms resulting from RWA feeding and that a callose-inducing signal may be transported in the phloem. Furthermore it is concluded that the absence of callose deposition in BCA-infested leaves is not due to a stronger induction of callose-degrading β-1,3-glucanases in this tissue, as compared to RWA-infested leaves.
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- Date Issued: 2009
A case of effective single-session treatment for attention deficit and learning problems in a routine clinical practice : the value of a transdiagnostic approach to case formulation
- Authors: Whitefield-Alexander, V , Edwards, David J A
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6274 , http://hdl.handle.net/10962/d1008274
- Description: This article reports a systematic clinical case study of the psychological assessment and treatment of Daniel (9), a coloured South African boy with a diagnosis of attention deficit hyperactivity disorder (ADHD) (inattentive type). The case is of scientific interest because: (1) there was only a single treatment session, in which contingency management training was delivered to Daniel’s parents and teacher; (2) there was evidence for the effectiveness of the intervention immediately and at two-year follow-up; (3) it documents the transportability to a South African context of an intervention developed by overseas research; (4) it documents the central role of case formulation in the delivery of effective psychological interventions; and (5) although Daniel met the criteria for ADHD, he also displayed symptoms of depression and social anxiety and the case supports the use of a transdiagnostic approach to case formulation. The conscientiousness with which his parents and teachers applied the programme was a major factor in the effectiveness of the intervention, and such rapid impact would not be possible where parents and teachers are unavailable or not co-operative. The publication of systematic case studies such as this one is important for the development of a local evidence-based practice in South Africa.
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- Date Issued: 2009
Application of neural networks to South African GPS TEC modelling
- Authors: Habarulema, John B , McKinnell, Lee-Anne , Cilliers, Pierre J , Opperman, Ben D L
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6807 , http://hdl.handle.net/10962/d1004193 , http://dx.doi.org/10.1016/j.asr.2008.08.020
- Description: The propagation of radio signals in the Earth’s atmosphere is dominantly affected by the ionosphere due to its dispersive nature. Global Positioning System (GPS) data provides relevant information that leads to the derivation of total electron content (TEC) which can be considered as the ionosphere’s measure of ionisation. This paper presents part of a feasibility study for the development of a Neural Network (NN) based model for the prediction of South African GPS derived TEC. The South African GPS receiver network is operated and maintained by the Chief Directorate Surveys and Mapping (CDSM) in Cape Town, South Africa. Vertical total electron content (VTEC) was calculated for four GPS receiver stations using the Adjusted Spherical Harmonic (ASHA) model. Factors that influence TEC were then identified and used to derive input parameters for the NN. The well established factors used are seasonal variation, diurnal variation, solar activity and magnetic activity. Comparison of diurnal predicted TEC values from both the NN model and the International Reference Ionosphere (IRI-2001) with GPS TEC revealed that the IRI provides more accurate predictions than the NN model during the spring equinoxes. However, on average the NN model predicts GPS TEC more accurately than the IRI model over the GPS locations considered within South Africa.
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- Date Issued: 2009
Suitability of total coliform beta-D-galactosidase activity and CFU counts in monitoring faecal contamination of environmental water samples
- Authors: Wutor, V C , Togo, C A , Pletschke, Brett I
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6477 , http://hdl.handle.net/10962/d1006165 , http://www.scielo.org.za/scielo.php?pid=S1816-79502009000100010&script=sci_arttext
- Description: Total coliforms are a group of bacteria found in high numbers in mammalian intestines; hence their presence in water indicates the possible contamination with faecal material. Total and faecal coliform counts were monitored over a period of 18 months using mFC, m-Endo and CM1046 media together with enzymatic assays on 215 environmental water samples obtained from the Eastern Cape Province of South Africa. A positive correlation, with an R2 value of 0.9393 was observed between faecal and total coliform colony units employing mFc and m-Endo media, and 0.8818 using CM1046 media. Also, a positive correlation was observed between Escherichia coli colony-forming units and β-D-galactosidase (B-GAL) activity (R2=0.8542). Overall, this study indicated that faecal contamination of environmental water samples could be monitored by measuring total coliform β-galactosidase activity and total coliform colony-forming units.
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- Date Issued: 2009