1,234 research outputs found
Evaluating a public sector organisation for SDI Readiness â The case of a South African government department
Spatial data infrastructure (SDI) facilitates the collection and sharing of geographic information developed by different organisations. As a result, SDI initiatives are occurring in different countries. Various government departments are implementing SDI in order to contribute to the achievements of its objectives. SDI assessments to evaluate the implementation thereof is also occurring from local levels to international levels. This paper establishes the availability of geographic information within the Department of Environmental Affairs (DEA) by describing DEAâs contribution to the South African SDI objectives and by assessing DEAâs SDI readiness.The qualitative method was used to collect data. The techniques used in this research were literature review, interviews, mainly in-depth interview, document and internet analysis.The results indicate that geographic information is available and the department continues to make more means to make it available. They also reveal that there are some challenges with respect to accessibility. Currently there is a process to make it even more easily accessible. The results show DEAâs willingness and capacity to contribute to the South African SDI. The voluntary participation in SDI activities and the ability to obtain additional funding for geographic information is a clear indicator of DEAâs willingness to contribute to SASDIâs objectives. The results contribute to the body of knowledge that if an SDI is still in the early stages of development, it is challenging to make conclusions on some of the key SDI assessment indices. Future research is required once South African SDI has reached mature stages
αSynuclein and Mitochondrial Dysfunction: A Pathogenic Partnership in Parkinson's Disease?
Parkinson's Disease (PD) is a complex, chronic, progressive, and debilitating neurodegenerative disorder. Neither a cure nor effective long-term therapy exist and the lack of knowledge of the molecular mechanisms responsible for PD development is a major impediment to therapeutic advances. The protein αSynuclein is a central component in PD pathogenesis yet its cellular targets and mechanism of toxicity remains unknown. Mitochondrial dysfunction is also a common theme in PD patients and this review explores the strong possibility that αSynuclein and mitochondrial dysfunction have an inter-relationship responsible for underlying the disease pathology. Amplifying cycles of mitochondrial dysfunction and αSynuclein toxicity can be envisaged, with either being the disease-initiating factor yet acting together during disease progression. Multiple potential mechanisms exist in which mitochondrial dysfunction and αSynuclein could interact to exacerbate their neurodegenerative properties. Candidates discussed within this review include autophagy, mitophagy, mitochondrial dynamics/fusion/fission, oxidative stress and reactive oxygen species, endoplasmic reticulum stress, calcium, nitrosative stress and αSynuclein Oligomerization
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Analysing the practical feasibility of FOSSGIS in military operations â A Cholera outbreak use case
Remaining ahead of the enemy in all circumstances is crucial to any military power. Geographic information systems (GIS) can provide the military commander with geospatial information about the theatre of war to assist with the planning and execution of a mission. Unfortunately, technology usually comes at a price. GIS is no exception. The cost of acquiring and maintaining GIS software licenses, as well as training staff in the use of the software, needs to be considered. The question arises whether open source software, which can be used without any software license expenses, is a feasible alternative in military operations. The problem is that the perception exists that open source GIS software is neither user-friendly nor mature enough to be used in military operations. This study evaluates the functionality of an open source desktop GIS product in a military operations use case. A list of specific GIS functionalities was compiled based on the literature study and by developing a use case. The functionalities were executed in QGIS. Results were compared against results of the same functionalities in ArcGIS, which is widely used in military operations. Results show that all GIS functions tested by this study could be performed by both software products. These results are interesting because it means that FOSSGIS can be successfully deployed by units or directorates that has limited funds available to expand the existing GIS capabilities for military operations
Standards for exchanging digital geo-referenced information
The purpose of this dissertation is to assess digital geo-referenced information and standards for exchanging such information, especially the South African National Exchange Standard (NES). The process of setting up a standard is exacting. On the one hand, the process demands a thorough scrutiny and analysis of the objects to be standardised and of all related concepts. This is a prerequisite for ensuring that there is unanimity about their meaning and inter-relationships. On the other hand, the process requires that the standard itself be enunciated as succinctly, comprehensibly and precisely as possible. This dissertation addresses both these facets of the standards process in the context of standards for exchanging digital geo-referenced information. The dissertation begins with an analysis of geo-referenced information in general, including digital geo-referenced information. In chapters 2 and 3, the various aspects of such information are scrutinised and evaluated in more detail. The examination of concepts is backed up by a comprehensive Glossary of terms in the domain under discussion. Chapter 4 examines the nature of standards. It also proposes a novel way to approach a standard for the exchange of digital geo-referenced information: namely, that it can be viewed as a language and can accordingly be specified by a grammar. To illustrate the proposal, NES is fully specified, using the Extended Backus-Naur Form notation, in an Appendix. Apart from the advantages of being a succinct and precise formal specification, the approach also lends itself to deploying standard tools such as Lex and yacc for conformance testing and for developing interfaces to NES, as illustrated in a second appendix. As a final theme of the dissertation, an evaluation of such standards is provided. Other standards that have been proposed elsewhere for purposes similar to that of NES are surveyed in chapter 5. In chapter 6, features of NES are highlighted, including the fact that it takes a relational approach. Chapter 7 concludes the dissertation, summarising the work to date, and looking ahead to future work. AFRIKAANS : Die doel van hierdie verhandling is om versyferde geo-verwysde inligting en standaarde vir die uitruil van sulke inligting te ondersoek, met spesifieke verwysing na die Suid- Afrikaanse Nasionale Uitruilstandaard (NES). Die proses om ân standaard op te stel is veeleisend. Aan die een kant vereis die proses ân volledige bestudering en ontleding van die objekte wat gestandaardiseer gaan word, asook van al die verwante konsepte. Hierdie is ân voorvereiste om te verseker dat daar oor hul betekenisse en onderlinge verwantskappe eenstemmigheid bestaan. Aan die ander kant vereis die proses dat die standaard so kernagtig, volledig en presies moontlik gestel moet word. Hierdie verhandeling spreek beide hierdie fasette van die standaardiseringsproses aan, en wel in die konteks van standaarde vir die uitruil van versyferde geo-verwysde inligting. DiĂ© verhandling begin met ân oorhoofse analise van geo-verwysde inligting, insluitend versyferde geo-verwysde inligting. In hoofstukke 2 en 3 word verskeie aspekte van diĂ© inligting in meer detail ondersoek en geĂ«valueer. Hierdie ondersoek van konsepte word deur ân omvattende woordelys van terme in die veld onder bespreking gesteun. Hoofstuk 4 ondersoek die aard van standaarde. Dit stel ook ân nuwe manier voor om ân standaard vir die uitruil van versyferde geo-verwysde inligting te benader, naamlik dat dit as ân taal beskou kan word, en dat dit gevolglik deur middel van ân grammatika gespesifiseer kan word. Om die voorstel te illustreer, word NES volledig in ân aanhangsel deur middel van die Uitgebreide Backus-Naur Vorm notasie gespesifiseer. Afgesien van die voordeel van ân kernagtige en presiese formele spesifikasie, ondersteun die benadering ook standaardgereedskap soos Lex en yacc wat vir konformeringstoetsing en vir NES koppelvlakke gebruik kan word, soos in ân tweede aanhangsel illustreer word. As ân finale tema van die verhandeling word ân evaluasie van tersaaklike standaarde voorsien. Standaarde wat elders vir soortgelyke doeleindes aan diĂ© van NES voorgestel is, word oorsigtelik in hoofstuk 5 beskou. In hoofstuk 6 word kenmerkende eienskappe van NES uitgelig, insluitend die feit dat dit op ân relasionele benadering gebaseer is. Hoofstuk 7 sluit die verhandeling af met ân opsomming van werk tot op datum en ân blik op toekomstige werk.Dissertation (MSc)--University of Pretoria, 1993.Computer Scienceunrestricte
Towards a JĆmon food database: construction, analysis and implications for Hokkaido and the Ryukyu Islands, Japan
One of the most entrenched binary oppositions in archaeology and anthropology has been the agriculturalist vs hunter-gatherer-fisher dichotomy fuelling a debate that this paper tackles from the bottom-up by seeking to
reconstruct full past diets. The Japanese prehistoric JĆmon cultures survived
without fully-developed agriculture for more than 10,000 years. Here we
compile a comprehensive, holistic database of archaeobotanical and archaeozoological records from the two ends of the archipelago, the northernmost
prefecture of Hokkaido and the southernmost island-chain of Ryukyu. The
results suggest JĆmon diets varied far more geographically than they did
over time, and likely cultivated taxa were important in both regions. This
provides the basis for examining how fisher-hunter-gatherer diets can fulfil
nutritional requirements from varied environments and were resilient in the
face of environmental change
The South African Spatial Data Infrastructure â Where are the Municipalities?
Many municipalities in South Africa, especially those in rural areas, do not have the resources to maintain the geospatial information required to deliver essential services. Conversely, National Geo-spatial Information (NGI), the national mapping agency (NMA), captures data themes required by municipalities but not at scales suitable for municipal purposes. In 2003, the South African Spatial Data Infrastructure (SASDI) was initiated through national legislation as the ânational technical, institutional and policy frameworkâ to govern public geospatial information. However, involvement of the countryâs more than 250 municipalities in SASDI has been limited. In order to better understand the role of municipalities in the development and implementation of SASDI, we reviewed this over four periods: (1) before 1994, i.e., before the new Constitution of South Africa came into force; (2) 1994 to 2000, when the idea of an SDI emerged through voluntary participation; (3) 2000 to 2009, when the SASDI legislation was enacted but nothing really happened; and (4) from 2010 to date, starting with the first meeting of the Committee for Spatial Information, the SASDI coordinating body. The review confirms that unless SASDI steps in to provide coordination mechanisms between different spheres of government, the NMA will continue to supply unsuitable data and municipalities will be left to their own devices. A SASDI that caters for diverse user needs through bottom-up influences could greatly improve local municipalitiesâ service delivery. We have used the results of our study to propose a governance framework where all spheres of government are involved in SASDI and municipalities have an opportunity to communicate their data needs from the bottom, upward
An HRD/DER-independent ER quality control mechanism involves Rsp5p-dependent ubiquitination and ER-Golgi transport
We have identified a new pathway of ER-associated degradation in Saccharomyces cerevisiae that functions separately from the HRD/DER pathway comprised of Hrd1p, Hrd3p, Der1p, and Ubc7p. This pathway, termed Hrd1p independent-proteolysis (HIP), is capable of recognizing and degrading both lumenal (CPY* and PrA*), and integral membrane proteins (Sec61â2p) that misfold in the ER. CPY* overexpression likely saturates the HRD/DER pathway and activates the HIP pathway, so the slowed degradation kinetics of CPY* in a hrd1Î strain is restored to a wild-type rate when CPY* is overexpressed. Substrates of HIP require vesicular trafficking between the ER and Golgi apparatus before degradation by the ubiquitin-proteasome system. Ubiquitination of HIP substrates does not involve the HRD/DER pathway ubiquitin ligase Hrd1p, but instead uses another ubiquitin ligase, Rsp5p. HIP is regulated by the unfolded protein response as Ire1p is necessary for the degradation of CPY* when overexpressed, but not when CPY* is expressed at normal levels. Both the HIP and HRD/DER pathways contribute to the degradation of CPY*, and only by eliminating both is CPY* degradation completely blocked
Adapting the Dyna-CLUE model for simulating land use and land cover change in the Western Cape Province
Models which integrate and evaluate diverse factors of Land Use and Land Cover (LULC) change can be used to guide planners in making more informed decisions and achieving a balance between urban growth and preservation of the natural environment. The implementation of these models at a provincial scale is however very limited in South Africa. LULC change models are valuable if their structures are based on a deep knowledge of the system under investigation and if they produce credible results. This study therefore investigates the suitability of LULC change models in simulating LULC changes at a provincial scale in a South African context. The Dyna-CLUE model was implemented using the following as inputs: spatial policies and restrictions; land-use type conversions; land use requirements (demands) and location characteristics. The model produced probability maps and simulation maps for the years between 1990 and 2014. Validation of the simulated maps was conducted using both visual and statistical analysis and the results indicated that the simulated maps were in good agreement with the validation map. This study contributes to the implementation of LULC change models at a provincial scale in a South African context. Knowledge derived from this study can be used by planners as a guide to effectively gauge the impacts that planning policies and other driving factors might have on future LULC patterns in the Western Cape Province
Introduction to the AfricaGEO 2018 Conference Special Issue of the South African Journal of Geomatics
No Abstrac
What is an address in South Africa?
Addresses come in many forms as they have a variety of uses. In our paper we illustrate the need for standardized addresses in South Africa by describing scenarios where standardized addresses are required, or where standardized addresses would improve the current situation. We present the eleven address types described in the current draft South African address standard (SANS 1883), which has been developed under the auspices of the South African Bureau of Standards. We go on to show that these address types represent an all-encompassing description of an address in South Africa. The address types have to accommodate the current situation where there are no mandated authorities that assign standardized addresses according to a set of guidelines, and we provide a critical evaluation of this situation. Our contribution is threefold: illustrating the need for standardized addresses, showing that there is an all-encompassing description for an address in South Africa, and describing the potential negative impact of the current lack of mandated authorities on unambiguous address specification and the benefits that address standardization would bring.http://www.sajs.co.za
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