Cost and time overruns on Mpumalanga Province infrastructure projects
- Authors: Phalanndwa, Shonisani Aaron
- Date: 2018
- Subjects: Project management -- South Africa -- Mpumalanga , Infrastructure (Economics) industrial management -- South Africa -- Mpumalanga Business enterprises -- South Africa -- Mpumalanga -- Finance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/34169 , vital:33248
- Description: Cost and time overruns in construction projects are a common issue affecting project performance, and Mpumalanga is no exception. Completion of any project within the estimated cost of a project is a basic criterion for success of any project. The success of any project highly depends on adequate availability and efficient management of various resources. Construction projects often face a lot of uncertainties, which places building construction projects at the risk of cost, time overruns as well as poor quality delivery. This study assesses the causes, effects and measures of minimising construction project cost and time overrun in the Mpumalanga Province. The data used in this study were derived from both primary and secondary sources. The primary data was collected through case study interviews with construction professionals, project owners, contractors and consultants involved in Mpumalanga construction projects. Findings from the case study revealed that clients inability to meet payment obligations on time, additional work requested by the client, proper feasibility study not done, ensuring transparency in awarding of contracts, contractors financial difficulties, late delivery of materials, contractors lack of experience, bribery and corruption involving the contractor or contractor’s team, and poor site management and consultants insufficient geotechnical investigations, insufficient/unknown information regarding site conditions during design phase, mistakes and discrepancies in design documents are the major causes of cost and time overruns that are incidental to project implementation in Mpumalanga. Furthermore the study also reveals that the major effect of cost and time overrun are: poor quality workmanship, total abandonment, and disputes, discouragement of investors, community unrest and service delivery is negatively affected. It was revealed that all stakeholders of construction parties are deeply involved in contributing to the causes of the problems, clients should bear the greatest responsibility and play the most important role in lessening the impact of cost and time overrun. Thus, interventions that could be adopted by the Mpumalanga province to achieve project delivery that is within estimated cost and time are: Government must adopt ‘financial assignment’ to deal with suppliers in order to supply materials to the contractor and have available funds for projects on time, soil investigation and testing should be conducted by clients prior to the commencement of a project; encourage whistleblowing and punish fraudsters more severely. Contractors must have enough cash before commencing of projects, v monitor financial spending of the projects and payments; consultants must review and approve design documents, shop drawings, and payments of contractor. It is recommended that training courses, seminars and workshops on project management should be made available to help improve the abilities of construction teams responsible for management and supervision of sites and client organisations should encourage whistleblowing, punish fraudsters more efficiently and pay commensurate reward to whistle-blowers in order to minimise cost and time overruns.
- Full Text:
- Date Issued: 2018
- Authors: Phalanndwa, Shonisani Aaron
- Date: 2018
- Subjects: Project management -- South Africa -- Mpumalanga , Infrastructure (Economics) industrial management -- South Africa -- Mpumalanga Business enterprises -- South Africa -- Mpumalanga -- Finance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/34169 , vital:33248
- Description: Cost and time overruns in construction projects are a common issue affecting project performance, and Mpumalanga is no exception. Completion of any project within the estimated cost of a project is a basic criterion for success of any project. The success of any project highly depends on adequate availability and efficient management of various resources. Construction projects often face a lot of uncertainties, which places building construction projects at the risk of cost, time overruns as well as poor quality delivery. This study assesses the causes, effects and measures of minimising construction project cost and time overrun in the Mpumalanga Province. The data used in this study were derived from both primary and secondary sources. The primary data was collected through case study interviews with construction professionals, project owners, contractors and consultants involved in Mpumalanga construction projects. Findings from the case study revealed that clients inability to meet payment obligations on time, additional work requested by the client, proper feasibility study not done, ensuring transparency in awarding of contracts, contractors financial difficulties, late delivery of materials, contractors lack of experience, bribery and corruption involving the contractor or contractor’s team, and poor site management and consultants insufficient geotechnical investigations, insufficient/unknown information regarding site conditions during design phase, mistakes and discrepancies in design documents are the major causes of cost and time overruns that are incidental to project implementation in Mpumalanga. Furthermore the study also reveals that the major effect of cost and time overrun are: poor quality workmanship, total abandonment, and disputes, discouragement of investors, community unrest and service delivery is negatively affected. It was revealed that all stakeholders of construction parties are deeply involved in contributing to the causes of the problems, clients should bear the greatest responsibility and play the most important role in lessening the impact of cost and time overrun. Thus, interventions that could be adopted by the Mpumalanga province to achieve project delivery that is within estimated cost and time are: Government must adopt ‘financial assignment’ to deal with suppliers in order to supply materials to the contractor and have available funds for projects on time, soil investigation and testing should be conducted by clients prior to the commencement of a project; encourage whistleblowing and punish fraudsters more severely. Contractors must have enough cash before commencing of projects, v monitor financial spending of the projects and payments; consultants must review and approve design documents, shop drawings, and payments of contractor. It is recommended that training courses, seminars and workshops on project management should be made available to help improve the abilities of construction teams responsible for management and supervision of sites and client organisations should encourage whistleblowing, punish fraudsters more efficiently and pay commensurate reward to whistle-blowers in order to minimise cost and time overruns.
- Full Text:
- Date Issued: 2018
Molecular characterisation of the chaperone properties of Plasmodium falciparum heat shock protein 70
- Authors: Shonhai, Addmore
- Date: 2007
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Proteins -- Purification Molecular chaperones Malaria -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3977 , http://hdl.handle.net/10962/d1004036
- Description: Heat shock protein 70 (called DnaK in prokaryotes) is one of the most prominent groups of chaperones whose role is to prevent and reverse protein misfolding. PfHsp70 is a heatinducible cytoplasm/nuclear localised Plasmodium falciparum Hsp70. PfHsp70 is thought to confer chaperone cytoprotection to P. falciparum during the development of malaria fever. The objective of this study was to examine the chaperone properties of PfHsp70 using a bioinformatics approach, coupled to in vivo and in vitro analysis. Structural motifs that qualify PfHsp70 as a typical Hsp70 chaperone were identified. Although PfHsp70 has a higher similarity to human Hsc70 than E. coli DnaK, in vivocomplementation assays showed that PfHsp70 was able to reverse the thermosensitivity of E. coli dnaK756 (a temperature sensitive strain whose DnaK is functionally compromised). Two residues (V401 and Q402) in the linker region of PfHsp70 that are critical for its in vivo function were identified. Constructs were generated that encoded the ATPase domain of PfHsp70 and the peptide binding domain of E. coli DnaK (to generate PfK chimera); and the ATPase domain of E. coli DnaK fused to the peptide binding domain of PfHsp70 (KPf). The two chimeras were tested for their ability to reverse the thermosensitivity of E. coli dnaK756 cells. Whilst KPf was able to reverse the thermosensitivity of the E. coli dnaK756 cells, PfK could not. Previously, PfHsp70 purification involved urea denaturation. Using a detergent, polyethylenimine (PEI), PfHsp70 was natively purified. Natively purified PfHsp70 had a basal ATPase activity approximately two times higher than the previously reported activity for the protein purified through urea denaturation. PfJ4, a type II Hsp40, could not stimulate the ATPase activity of PfHsp70 in vitro. Arch and hydrophobic pocket substitutions (A419Y, Y444A and V451F) were introduced in the PfHsp70 peptide binding domain. Similar substitutions were also introduced in the KPf chimera. PfHsp70-V451F (hydrophobic pocket mutant) had marginally compromised in vivo function. However, a similar mutation (V436F), introduced in KPf abrogated the in vivo function of this chimera. The arch and hydrophobic pocket derivatives of PfHsp70 exhibited marginally compromised in vivo function, whilst equivalent mutations in KPf did not affect its in vivo function. The ability of PfHsp70 and its arch/hydrophobic pocket mutants to suppress the heatinduced aggregation of malate dehydrogenase (MDH) in vitro was investigated. Whilst PfHsp70 arch mutants displayed marginal functional loss in vivo, data from in vitro studies revealed that their functional deficiencies were more severe. This is the first study in which an Hsp70 from a parasitic eukaryote was able to suppress the thermosensitivity of an E. coli DnaK mutant strain. Findings from the in vivo and in vitro assays conducted on PfHsp70 suggest that this protein plays a key role in the life-cycle of P. falciparum. Furthermore, this study raised insights that are pertinent to the current dogma on the Hsp70 mechanism of action.
- Full Text:
- Date Issued: 2007
- Authors: Shonhai, Addmore
- Date: 2007
- Subjects: Heat shock proteins Plasmodium falciparum Protein folding Proteins -- Purification Molecular chaperones Malaria -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3977 , http://hdl.handle.net/10962/d1004036
- Description: Heat shock protein 70 (called DnaK in prokaryotes) is one of the most prominent groups of chaperones whose role is to prevent and reverse protein misfolding. PfHsp70 is a heatinducible cytoplasm/nuclear localised Plasmodium falciparum Hsp70. PfHsp70 is thought to confer chaperone cytoprotection to P. falciparum during the development of malaria fever. The objective of this study was to examine the chaperone properties of PfHsp70 using a bioinformatics approach, coupled to in vivo and in vitro analysis. Structural motifs that qualify PfHsp70 as a typical Hsp70 chaperone were identified. Although PfHsp70 has a higher similarity to human Hsc70 than E. coli DnaK, in vivocomplementation assays showed that PfHsp70 was able to reverse the thermosensitivity of E. coli dnaK756 (a temperature sensitive strain whose DnaK is functionally compromised). Two residues (V401 and Q402) in the linker region of PfHsp70 that are critical for its in vivo function were identified. Constructs were generated that encoded the ATPase domain of PfHsp70 and the peptide binding domain of E. coli DnaK (to generate PfK chimera); and the ATPase domain of E. coli DnaK fused to the peptide binding domain of PfHsp70 (KPf). The two chimeras were tested for their ability to reverse the thermosensitivity of E. coli dnaK756 cells. Whilst KPf was able to reverse the thermosensitivity of the E. coli dnaK756 cells, PfK could not. Previously, PfHsp70 purification involved urea denaturation. Using a detergent, polyethylenimine (PEI), PfHsp70 was natively purified. Natively purified PfHsp70 had a basal ATPase activity approximately two times higher than the previously reported activity for the protein purified through urea denaturation. PfJ4, a type II Hsp40, could not stimulate the ATPase activity of PfHsp70 in vitro. Arch and hydrophobic pocket substitutions (A419Y, Y444A and V451F) were introduced in the PfHsp70 peptide binding domain. Similar substitutions were also introduced in the KPf chimera. PfHsp70-V451F (hydrophobic pocket mutant) had marginally compromised in vivo function. However, a similar mutation (V436F), introduced in KPf abrogated the in vivo function of this chimera. The arch and hydrophobic pocket derivatives of PfHsp70 exhibited marginally compromised in vivo function, whilst equivalent mutations in KPf did not affect its in vivo function. The ability of PfHsp70 and its arch/hydrophobic pocket mutants to suppress the heatinduced aggregation of malate dehydrogenase (MDH) in vitro was investigated. Whilst PfHsp70 arch mutants displayed marginal functional loss in vivo, data from in vitro studies revealed that their functional deficiencies were more severe. This is the first study in which an Hsp70 from a parasitic eukaryote was able to suppress the thermosensitivity of an E. coli DnaK mutant strain. Findings from the in vivo and in vitro assays conducted on PfHsp70 suggest that this protein plays a key role in the life-cycle of P. falciparum. Furthermore, this study raised insights that are pertinent to the current dogma on the Hsp70 mechanism of action.
- Full Text:
- Date Issued: 2007
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