A histological assessment allows aquatic scientists to assess fish health in polluted aquatic ecosystems at tissue and cellular level. However, a firm knowledge and understanding of normal histological structure is essential to ensure accurate and objective results. Hence, the histologist must be able to distinguish between toxicant induced lesions and the range of histological characteristics considered to be normal for that specific species. However, limited histological reference material and data describing normal conditions are available for southern African fish species. The aim of this baseline study was to establish reference material, both qualitative and quantitative, for two southern African freshwater fish species used as indicator species in toxicity studies at the University of Johannesburg, Clarias gariepinus and Oreochromis mossambicus. The reference material includes descriptive histology of selected target organs, and the associated values and intervals for related quantitative health aspects including somatic indices, condition factor, blood parameters (haematocrit and plasma proteins) and quantitative histological results. Essentially, this project originated from a need to better understand the normal histology of C. gariepinus and O. mossambicus, as a range of histological characteristics were identified in control groups in previous toxicity studies which could not be confirmed to be associated with normal conditions. To be able to conduct a baseline study, with the purpose of establishing reference material, it was essential that the history of the specimens be known and documented including age, sexual maturity, nutritional status and physical and chemical water quality data. The project therefore involved the breeding of fish specimens under controlled conditions. A subsequent necropsy and qualitative and quantitative histological assessments were executed on five target organs (usually included in toxicity studies within the department): liver, gills, gonads, heart and kidney. Fish of both species were bred in an environmental room in reconstituted, reverse osmosis water and reared until sexually mature. Twenty specimens with an approximately 50:50% sex ratio were collected for both species. A necropsy was performed on each specimen and tissue samples of the selected target organs were processed using standard techniques, and prepared for the qualitative and quantitative histological assessments using light microscopy. The results The results showed that no macroscopic abnormalities were identified during the necropsy regarding external features or internal organs of the specimens within the sample groups, and all fish appeared to be in good health. The target organs were then examined microscopically, followed by a description of the normal histological structure (qualitative assessment). In addition, the target organs were assessed by means of a specific quantitative histological assessment protocol, which provides a standardised methodology of criteria to objectively assess fish health (quantitative assessment). Histological alterations identified during this assessment were quantified and subsequent reference index values could be calculated for each organ. / Dr. G.M. Pieterse

The need to monitor fresh water ecosystems for pollution is increasing, as is the need to develop a biomarker sensitive to a range of environmental insults. Recently, heat shock proteins have been identified as possible biomarkers of environmental contamination. However, evaluation as to their use as a biomarker of metal contamination in fish species endemic to Southern Africa is limited. The purpose of this study was to identify what members of the 70 kDa family of heat shock proteins (Hsp70) were present in the liver of Oreochromis mossambicus, and if their accumulation was altered after short-term (96 hour) exposure to aqueous copper. In addition to copper exposure, the effect of acclimation media was also examined. Tissue-level analysis was done by means of histological examination so as to determine if alterations in the accumulation of the Hsp70 family had a marked effect on the structural integrity of the liver. Specimens of Oreochromis mossambicus acclimated in either aged tap water or borehole water were placed in flow-through systems and exposed to either 10% or 20% of the LC50 value of cupric chloride for a duration of 96 hours. Control groups were run in conjunction with the exposure groups so as to set control values by which to compare. Heat shock protein analysis was done by Western blotting after separation of hepatic proteins by SDS-PAGE. For the purpose of histological analysis, representative samples were randomly selected. Analysis of the hepatic heat shock protein 70 family identified the presence of three (3) members, each of a different molecular weight. These included members of 70 kDa (Hsp70), 74 kDa (Hsp74) and 76 kDa (Hsp76). In addition to these findings, it was found that Oreochromis mossambicus accumulated high levels of particular members of the heat shock protein 70 family under unstressed conditions, affording the fish adaptability to environmental extremes. Furthermore, individuals acclimated in aged tap water showed decreased Hsp76 accumulation after exposure to sub-lethal copper concentrations, whereas those individuals acclimated in borehole water retained relatively high levels of Hsp76. Additionally, it was shown that the hepatic structure deteriorated in those individuals acclimated to the aged tap water after copper exposure, with observed increases in vacuolation, number of macrophage centres present and the occurrence of intracellular golden-brown granules. However, there was little change from the already-altered hepatic structure of those individuals acclimated in borehole water, with conspicuous golden-brown granules the most obvious histopathological condition present. Histological examination therefore proved to supplement the heat shock protein results obtained. This study thus concluded that a decrease in the accumulation of the Hsp70 family resulted in a negative organismal response, initiating deleterious alterations in the hepatic structure. Additionally, this study concluded that past water quality has a marked effect on a given biomarker response, and should be taken into careful consideration when conducting biomarker studies. / Prof. J.H.J. Van Vuren

Magister Philosophiae (Land and Agrarian Studies) - MPhil(LAS) / This study is about the place of traditional authorities in local level land administration and rural governance in contemporary Mozambique. It came about as a result of the publication of the Decree 15/2000 that recognised traditional authorities after their abolition more than 20 years earlier. This study seeks to examine four inter-related themes: the role of traditional authorities in local level land administration in Mozambique; why the government recognised traditional authorities in the year 2000 after having abolished them more than 20 years earlier; whether the recognition of hereditary traditional authorities is consistent with principles of democracy; and lastly to investigate whether the practices taking place on the ground are an expression of democracy as envisaged by the country’s constitution. The study is based on documental research on the subject, as well as on fieldwork in the community of Chirindzene, Gaza Province in Southern Mozambique. It argues that generalisations about the role of traditional authorities in local level land administration may be misleading. Drawing from the case study in Chirindzene, it shows that it was only the lowest level of the traditional authority structure (the lineage level) that continued having influence in land allocation and distribution after independence in this area. With regard to the recognition of traditional authorities, the study argues that an appreciation of the changing global context is important to understand this dramatic shift. The study argues that the Decree 15/2000 and its regulations are weakening the democratic experience initiated in 1970s by allowing rural populations be ruled by hereditary rulers who are not elected. For this reason, the rural population does not enjoy full citizenship rights because they are ruled by both elected structures and appointed ones. / South Africa

Magister Artium - MA / More and more, research is becoming the core business of every university. There are a number of reasons as to why governments are encouraging their universities to make research activities a priority. Research leads to birth of new knowledge and theory of the world. Such new knowledge drives the economies of the world. In this regard, academic libraries have been able to provide the tools that guide clients through an avalanche of information and assist researchers to identify what meets their particular needs. However, academic libraries are facing some challenges as a result of various changes in scholarly communication as they are no longer regarded as the sole primary provider of information to researchers. The aim of this study was to investigate the role of library services in the research of postgraduate students at the University Eduardo Mondlane (UEM) in Mozambique. The study looked at the services the library offered to postgraduate students, the sources of information most used by postgraduate students, the research information needs of postgraduate students, the ways the postgraduate students access research materials and the challenges that postgraduate students encounter when using the System of Libraries at the UEM. The first research question was answered by reviewing the professional literature as well the empirical data obtained from the librarians via interviews. The rest of the questions were answered by the students via questionnaires as well as interviews with the library staff. The researcher self-administered a questionnaire to 200 registered postgraduate students at the UEM and conducted interviews with seven librarians. The study adopted the Multiple Constituencies Model which each of its domains effectively helping in interpreting the results of the study. The study found that between 57 (32.3%) and 58 (33%) postgraduate students use the library to search for prescribed course materials and research related work. Furthermore, the study found that 152 (88.4%) students used the Internet to search for information. Although the study showed students used the library, the major challenges that students between 35(19.9%) and 96(54.5%) faced included poor English literacy skills, unstable Internet and outdated materials.

Philosophiae Doctor - PhD / Since the earlier 1970s the government of Mozambique has been carrying out legal, political, economic and institutional reforms which are culminating in the establishment of the current fisheries governance systems. An important achievement of these reforms is the political recognition the government has given to the importance of subsistence fishing and its incorporation into policy instruments such as the Fisheries Master Plan II (2014-2019) and the Artisanal Fisheries Development Strategy (2009-2015). In these policy documents, fisheries authorities put subsistence fisheries on top of priorities. However, the practice in Mozambique’s fisheries is indicating that, despite this recognition, subsistence fishers remain amongst the most vulnerable groups, particularly at district and village levels. The objective of this study is to understand the patterns of inclusion and exclusion of subsistence fishers from the fisheries governance spaces in Mozambique with particular emphasis on Palma district (Cabo Delgado province). The study uses the concept of Action Spaces to situate the nature of opportunities that are being created under these reforms. A critical finding of this study is that, the institutions for fisheries governance being created by the government at district and community levels are not creating a functional mechanism for subsistence fishers to participate, access opportunities, and bring their voices into decision-making systems. As a result, subsistence fishers are creating their own spaces which are based on informal structures and relations to sustain their livelihoods. The study resorts to the institutional governance insights to understand the factors that may determine the interactions between the formal and informal action spaces while improving the contribution of subsistence fisheries to the livelihoods and food security of the vulnerable groups.

People and elephants share landscapes throughout Mozambique. Here elephant conservation management focuses on protected areas but fails to address the conflict that exists between elephants and people. In this thesis I develop a landscape approach to conflict mitigation that is designed to accommodate the needs of people and of elephants in human-dominated landscapes. Mozambique faces a dilemma: politically it is required to reduce poverty while at the same time adhere to international agreements and requirements to protect biodiversity with relatively scarce financial resources. Reactive mitigation of human-elephant conflict (HEC) at the site-specific scale have proven to be costly and with low efficacy. A shift from reactive to proactive HEC mitigation approaches at the county-wide scale (e.g. a district level, the administrative planning body) may provide opportunities to reconcile such apparent contrasting requirements in Mozambique. The elephant population of Mozambique is fragmented and remnant sub-populations are limited to clusters of protected areas in a matrix of human-dominated landscapes. A meta-population perspective may accommodate this spatial structuring and allow for a conservation plan that ensures population persistence and moderate impacts with other species in the landscape. I assessed HEC throughout human-dominated landscapes of Mozambique to examine some assumptions associated with the landscape approach advocated here. I used spatially explicit human activity data, landscape features and elephant distribution at the grid cell of 25 km2 and at the district scale to test the practicality of landscape approaches to elephant conservation and mitigating HEC in the human-dominated landscapes of Mozambique. I then tested whether human activities have significant impacts on elephant numbers and distribution across Mozambique. Furthermore I tested if the costs and benefits of sharing space with elephants influenced HEC. Thereafter, I explored at the grain scale of 25 km2 if the degree of overlap between them on the use of resources can be used to predict the likelihood of HEC across the landscape. Direct and indirect human activities explained trends and rates of elephant population changes in Mozambique. Because most rural households of Mozambique rely on subsistence farming by extracting or cropping from the land, primarily for their own purposes, living close to elephant refuge areas represented a potential risk to humans. However, conflict with elephants does not centre on food security, but on lifestyle being affected by the presence of elephants, which itself was a function of human density. Rodents and insects are the primary agents responsible for food loss during food storage. HEC was not a function of elephant density – a combination of human density, percent cultivated area and human population growth rate best explained HEC incidences. Although at human densities beyond 60 people/km2, elephants disappeared, at low levels of land transformation and low human densities people and elephants co-existed, which may induce higher incidences of HEC. Proximity to roads and suitable land for agriculture were the best predictors for HEC in the rural areas of Mozambique. These results imply spatially driven causes of HEC. These findings supported assumptions that conservation landscapes embedded in different land uses that accommodate ecological needs of people and elephants as well as the likelihood of severity of HEC can ensure elephant conservation without forcing people into poverty. While reactive HEC mitigation actions at site-specific scales are attractive for local communities, proactive measures at the landscape scale may be more effective in the rural context of the distributional range of elephants in Mozambique. HEC can be mitigated proactively through an effective land-use planning that involves zonation and implementation. To address this I extrapolated the relevant findings from resources selection functions models at the 25 km2 grain scale for study locations to a country-wide scale and proposed a model of a likelihood of HEC. The country-wide HEC model yielded high predictive power and confirmed protected areas as sites of high elephant dependability. These models indicate focal areas for short to medium term reactive HEC mitigation measures and local community programs at specific site level. This dissertation suggests that human and elephant co-existence is possible in Mozambique. The apparent increase of HEC is not a function of numbers of elephants but of improper land use planning. In this thesis I argue in favour of a landscape approach to mitigate conflict between elephants and people. This approach should be considered in all national plans that aim to reduce conflict and enhance conservation. / Thesis (PhD)--University of Pretoria, 2012. / Zoology and Entomology / unrestricted

Fishes of African floodplains typically comprise populations having short life cycles, relatively few age groups, more generalised feeding behaviour, and which experience spawning success that is strongly influenced by abiotic factors such as hydrological regime of the river, climatic seasonality and habitat characteristics. In addition, African river-floodplain ecosystems do not have appropriate predictive models for estimating yield in these ecosystems. While most predictive models developed to date for floodplain fisheries have taken into account morpho-edaphic factors, they have generally excluded climatic factors as a mega-determinant of the variability of floodplain fisheries. The principle aim of this thesis has been to develop a predictive management model that incorporates data on essential biological aspects of the target species, characteristics of the habitat as well as overall climatic factors, and thus allow for adaptive management of the fisheries in a continuously fluctuating floodplain environment. Lower Shire Floodplain (34 ⁰ 45’ – 35 ⁰ E and 16 ⁰ 00’-17 ⁰ 15’ S) in Malawi, one of the major rivers-floodplains in the Zambezi Basin, was used to test this type of model. The major hypothesis tested in this study was that “the dynamics of the fishery of Lower Shire Floodplain are driven by and adapted to the seasonal, but predictable, hydro-climatic regime of the floodplain”. The specific objectives were: to describe the floodplain’s climate and hydrological pattern; to develop a quantitative characterisation of the major habitats of the Lower Shire Floodplain; to assess the fishery in terms of size, gear utilisation, gear selectivity and yield; to assess the biological parameters of the target species, necessary for the management of the fishery; to analyse how water fluctuation in the floodplain affects the recruitment and life history of the two target species; and to develop of a predictive hydro-climatic model to benefit the management of the fisheries. The climate of the floodplain was characterised by low (765 ± 198 mm) and fairly variable (Cv = 27%) rainfall, which largely occurred between December and January. The area was generally humid (mean RH 68%), with mild to hot (25- 33ºC) and variable monthly mean diurnal (12ºC) temperature. Four quarterly hydro-climatic seasons were identified and comprised: Quarter 1 (Jul-Sep) characterised by hot, dry weather with a low flood regime; Quarter 2 (Oct-Dec) hot, windy, wet weather with low-but-rising flood regime; Quarter 3 (Jan-Mar) hot humid, wet weather with the flood regime at peak; and Quarter 4 (Apr-Jun) humid and cool weather with receding flood regime. The annual hydrograph of the floodplain was represented by four categories of flood regime as: low (Jul-Sept), low-but-rising (Oct-Dec), peak (Jan- Mar), and falling (Apr-Jun). The floodplain experienced a water deficit of 95.1 mm.year⁻¹, and it was hypothesised that ground water recharge maintained water in the floodplain the rest of the year. Three major habitats were identified in the floodplain. The river-floodplain, characterised by deep fast-flowing water, sandy substrate and little emergent vegetation; the permanently connected lagoons, were shallow (≤ 2 m) with sandymud bottom and slow flowing water; and the seasonally connected lagoons had slowflowing stagnant water, with comparatively more emergent and floating vegetation. Physicochemical characteristics of the habitats varied significantly with hydroclimatic seasons (one-way ANOVA, p ≤ 0.05), indicating the influence of flood regime, which joined the habitats in a non-equilibrial spatial distribution. Consequently, during receding and low flood regimes river-floodplain and permanently connected lagoons exhibited similar characteristics while all three habitats had similar characteristics during the rising and peak flood regimes. It was, therefore, concluded that in floodplains, habitats shift horizontally and vertically according to the water level. Gill nets, cast nets, long line, and fish traps accounted for 99% of the total count of gears, and hence considered the major fishing sectors. Two principal species in the floodplain were the catfish Clarias gariepinus and the cichlid Oreochromis mossambicus. Length-at-maximum-selectivity (ø) and length-at-50%-sexual-maturity (Lm₅₀) for each of the two species showed that although they were selected into the four fishing sectors at lengths above maturity, maximum selectivity into the long line occurred at a length before maturity for O. mossambicus. In addition, the width of the gamma selectivity function (σ) indicated that a considerable proportion of juveniles of the two species were also selected. Therefore, it was decided that management for the floodplain be centred on controlling over-fishing and preserving the spawner stock, by banning seine and mosquito nets, and closing river-floodplain and permanently connected lagoons to fishing during the low flood regime. There were significant seasonal variations in CPUE, lowest in the low flood, and highest during the peak flood regime. Sectioned otoliths were used to determine the age and growth of the two principal species in the floodplain. Marginal zone analysis revealed that annulus formation in all the species occurred during the period of low air and water temperatures, high evaporation and receding water levels, hence a high rate of desiccation and negative water budget. For O. mossambicus, maximum age reached was 6 years while in C. gariepinus it was 9 years. The 3-parameter von Bertalanffy growth model adequately described growth as lt = 177.6(1-e⁻·⁴⁴⁽t ⁺ ¹·⁴³⁾) mm TL for O. mossambicus and lt = 502.9(1-e⁻°·³¹⁽t ⁺ ¹·⁹²⁾) mm TL for C. gariepinus. Female O. mossambicus reached 50%-sexual-maturity at 109 mm SL, while males matured at 105 mm, and both male and female C. gariepinus reached Lm₅₀ at 249 mm SL. The breeding seasons of both O. mossambicus and Clarias gariepinus were between September and March, with modal peaks in January and November, respectively. The annual total mortality rates (Z) were 0.62 ± 0.18 yr⁻¹ for O. mossambicus and 0.93 ± 0.47 yr⁻¹ for C. gariepinus. The mean empirical estimates of natural mortality (M) were 0.46 yr⁻¹ for O. mossambicus and 0.50 year⁻¹ for C. gariepinus, and fishing mortality (F) was calculated as 0.16 yr⁻¹ for O. mossambicus and 0.43 yr⁻¹ for C. gariepinus. The overall exploitation level (Z/K) was 1.41 for O. mossambicus and 3.01 for C. gariepinus. Given that the Z/K ratio was >1, it was asserted that both O. mossambicus and C. gariepinus were mortality-dominated and fairly heavily exploited. However, potential for sustainable exploitation existed since both species showed signs of resilience due short longevity and high rate of natural mortality. Given the limitation of simple exponential models of fish mortality and growth under the situation of seasonal fluctuation of water levels, a simple predictive hydroclimatic- fisheries model was developed. The model predicted the life-history and production parameters fairly accurately (0.53 ≤ r² ≥ 0.98, p ≤ 0.05), and showed that environmental and biological events in the floodplain significantly (0.43 ≤ r² ≥ 0.91, p ≤ 0.05) followed the periodic function of time (day-of-the-year), hence, strongly seasonal. In addition, the flood-pulse preceded all the major biological events, with predicted phase lags established at 55.6º for peak flood, 157.2º, 260.1º, 334.6º and 341.4º for condition factor for O. mossambicus, recruitment, spawning period for O. mossambicus and C. gariepinus, respectively. Therefore, it was recommended that water obstruction on the Shire River must ensure sufficient water flow during the peak flood and spawning period to allow flooding and inundation of the floodplain in order to create habitat favourable for spawning and feeding as well as improve recruitment.

Mozambique was a Portuguese province governed in terms of Portuguese legislation and principles. After the Mozambican independence in June 1975, and during the decade thereafter, all Portuguese legislation were re-evaluated and replaced by new legislation based on socialist/communist philosophies, ultimately culminating in a centralised economy, which was governed according to Marxism/Leninism principles. In terms of this maxim, the primary objectives was to favour and protect state owned companies, resulting in the nationalisation of almost all of the private sector, thus eradicating competitiveness among the economic operators, and leaving the country to become one of the poorest in the world. The implemented political philosophy and associated economic principles furthermore impacted so adversely on the economy that critical changes were required to save the economy from collapse. New economic and political reforms and directives were introduced, moving the country from a socialist orientation to an open economy, a process that was implemented with the support of the International Monetary Fund and the World Bank. This process was highly complex and arduous, culminating in more often than not, failed implementations in the various sectors of the economy. One such sector, the Construction Engineering Industry is faced with collapse as a result of the complexities of the transition process. Against this background, ‘corrective’ economic legislation aimed to restructure the economy, was designed and implemented, only to result in high taxes and duties being paid by private companies. The present decline in foreign direct investment in the Construction Engineering Industry due to the current social and political uncertainty is of particular concern. More specific, the high interest bank rates on loans, the high duty rates for construction materials to be imported, the current judicial system which is viewed as ineffective in solving complex problems involving the industry, unfair labour laws which protect unproductive workers, and the high levels of bureaucracy, are all factors impacting adversely on any management effort to ensure the sustainability and growth of the Construction Engineering Industry in Mozambique. The Southern African Development Community (SADC) was constituted with the aim of creating an integrated and harmonious development strategy for each of its member countries, due to the fact that each country has its own culture, political dispensation, judicial system, labour laws and economic and fiscal structures. As the Construction Engineering Industries within each SADC country, by implication are subjected to differentiated operating environments and unique complexities, the solution as proposed by the SADC has the potential to culminate in a feasible option for the industry as a whole. For the Construction Engineering Industry of Mozambique however, the proposed solution of the SADC would not serve as a viable or feasible solution. This is due to the fact that the Construction Engineering Industry in Mozambique is not stable and close to collapse as a result of the plethora of inhibiting factors adversely impacting the industry. Against this background the research problem for this thesis reads as follow: “The Construction Engineering Industry in Mozambique is operating within the context of an unstructured complex management paradigm, calling for an evolutionary solution to mitigate the complexities and ensure sustainability and growth” The primary objective of this thesis is to establish to what extent an evolutionary systems approach model could facilitate paradigmatic change in the management of construction engineering in Mozambique to ensure its sustainability and growth. This objective will be met through:  An in depth analysis of the complex phenomena pertaining to the construction engineering industry in Mozambique deploying the enquiry capabilities of the Biomatrix Systems Approach.  Benchmarking the operating environments of the Construction Engineering Industries of South Africa and Mozambique.  The formulation of an evolutionary, unique viable approach so structured to address the complexity associated with construction engineering in Mozambique. This evolutionary approach will be fundamentally based on the Systems Approach and associated Viable Systems Model, juxtaposed with this authors’ own contribution, to ultimately facilitate paradigmatic change in the Mozambican Construction Engineering Industry to mitigate the research problem set for this thesis. / Prof. Dr. L. Pretorius Prof. Dr. J.A. Watkins

Ph.D. / Heavy metals like copper are toxicants commonly found in mining, industrial, agricultural and waste effluents in South Africa¡¯s riverine systems. In high concentrations these metals could have a negative effect not only on river systems, but also on fish populations. It is therefore important to determine the effect of these heavy metals on the fish at an early stage, before the fish show any sign of being exposed to the pollutants and before any bodily functions are affected. It is known that polluted water, especially heavy metal pollution like copper, can cause physiological and biochemical alterations in fish. Histopathology is a mechanism, which can provide an indication of fish health by determining early injury to cells and can therefore be considered an important tool to determine the effect of pollutants like copper on fish tissue. At present very little is known about the effect of toxicants on the histology of fish tissue of freshwater fishes in South Africa. This is important in gonads, where many variables not only in different fish species, but also in the number of developing germ cells in the testes exist. The large number of fish species and the variation in their anatomy and reproductive patterns make knowledge of the anatomy of all fish species difficult. In order to perform a histopathological analysis, it is important to be familiar with the normal histology of the fish organs that are being investigated. It was therefore necessary to describe the histology of selected organs in South Africa¡¯s freshwater fish species. The Mozambique tilapia, O. mossambicus was chosen as test organism and copper was selected as toxicant. The normal morphology and histology of the testes of O. mossambicus were described in order to serve as a baseline study and to provide histological parameters for further toxicological work on the gonadal histopathology of fish. Fish were exposed to sub-lethal concentrations of copper (CuCl2) for a short-term (96 hours) in experimental flow-through systems under controlled laboratory conditions (23 ¡¾ 1¨¬C). An external investigation of each of the 30 control and 40 copper exposed fish was performed. Standard length, body mass and gonadal mass were recorded and the maturity of each fish was obtained histologically. A light and electron microscopic examination was performed in order to describe the histology and histopathological changes. The histopathological changes were obtained by comparing the histology and ultrastructure of the testis of the control group with the information obtained for the testes that were exposed to copper. Fish obtained from the control group that were run simultaneously with every exposure group were used to describe the normal histology of the testes of O. mossambicus. The aim was to describe the normal morphology and histology of the testes of O. mossambicus so that the information obtained during this investigation could serve as a baseline study when dealing with toxicity studies. The different germ cells of the spermatogenesis process were also described with a view to assess not only the reproductive pattern, but also to provide histological parameters which might form a basis for any toxicological work on the gonadal histopathology of fish. Identification of reproductive biomarkers requires an understanding of all the principal cellular components of the testes and their normal range of variation. The cellular components that were described are the Sertoli and Leydig cells as well as the primary and secondary spermatogonia, primary and secondary spermatocytes, spermatids and spermatozoa. The information on the GSI, gonad reproductive stages as well as the histological examination provided the baseline which was needed for comparison of the testes of fish that were exposed to copper. The cellular and sub-cellular responses at light and electron microscopic level were examined to determine early cell changes and damage in the testes which were caused by different sublethal exposures of copper. There were no differences in the gross structure of the testes of the control group and the group that were exposed to copper. The testes of the fish that were exposed to 0.16, 0.40 and 2.0 mg Cu/§¤ all revealed disorganisation of the lobules, disintegration of the spermatogonia as well as disintegration of the interstitial tissue. The exposure of fish to sublethal concentrations of copper induced histopathological changes in the testes of all three groups of fish that were exposed to copper. The results also showed that the intensity of the histopathological changes increased with an increase in the concentration of copper. As a biomarker of exposure to toxicants, histopathology represents a useful tool to asses the degree of pollution. The results from this investigation showed a decrease in the GSI after being exposed to copper, when compared with the control groups, which were not exposed to copper. The information on the effect of copper on the GSI, gonad reproductive stages as well as the histological examination also provides information on gonadal health and maturational stage. This information however provides structural, rather than functional information regarding gonadal health. The results showed that the GSI and gonadal staging should be used together with the gonadal histopathology in order to provide a baseline for comparison when dealing with other toxicological studies. The information obtained during this investigation showed that fish histology and histopathology could be used as a biomarker to provide information on the effect of heavy metals on fish health. It is however suggested that the information obtained during this investigation should be extended to field investigation in order to be validated as a reliable histopathological biomarker. / Prof. J.H.J. van Vuren Prof. G.J. Steyn

Orientador: Ariovaldo Denis Granja / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-27T15:53:50Z (GMT). No. of bitstreams: 1 Muianga_ElisaAtaliaDaniel_M.pdf: 6166290 bytes, checksum: f57a311dba2efbb258b10424ee9b1691 (MD5) Previous issue date: 2015 / Resumo: Desvios de custos e prazos ainda são um grande desafio na construção civil. A execução do empreendimento é muitas vezes repleta de atrasos e custos adicionais, causados por vários fatores, que acabam encarecendo a construção. Em determinados países como Moçambique, as causas específicas não são verdadeiramente conhecidas, existem apenas percepções intuitivas e fragmentadas sobre os fatores que influenciam estes desvios. O objetivo desta pesquisa é apurar os fatores críticos que mais contribuem para a ocorrência de desvios de custos e prazos em empreendimentos do subsetor edificações de Moçambique. Para a busca de resultados de estudos primários, foi utilizada a Systematic Literature Review (Revisão sistemática de literatura ¿ RSL). Informações relevantes foram extraídas dos artigos selecionados e, posteriormente, sintetizadas para determinar uma estrutura de categorização e respectivos fatores responsáveis por estes desvios. A literatura existente até o momento sobre desvios de custos e prazos se mostrou multifacetada, com 92 artigos publicados em 46 fontes diferentes. A maioria das pesquisas teve como foco o estudo de alguns destes fatores em particular, enquanto que esta pesquisa procurou classificá-los e sintetizá-los de forma a possibilitar uma visão mais abrangente sobre o fenômeno. Assim, nove categorias foram identificadas e propostas com base em seus determinantes: (i) atividades e equipamentos; (ii) gerenciamento; (iii) projeto e documentação; (iv) financiamento; (v) aspectos ambientais e econômicos; (vi) organização; (vii) contratos; (viii) alterações de escopo e (ix) relações governamentais. Além disso, 95 fatores de influência para a ocorrência destes desvios foram identificados e anexados às categorias pertinentes. Após a RSL, o método de pesquisa para a sequência deste estudo é o Survey. Para isso, foi aplicado um questionário para determinação da relevância dos fatores de desvios de custos e prazos obtidos por meio da RSL, junto a 272 construtoras moçambicanas. Os resultados apresentaram 20 fatores estatisticamente relevantes para a ocorrência de desvios em empreendimentos moçambicanos. Com base nos fatores, foram apresentadas diretrizes para a redução dos impactos que esses fatores causam durante os empreendimentos que poderão ser validadas em estudos futuros / Abstract: Cost and time overruns are recurrent challenges in construction projects. In project implementation there are often delays and additional costs caused by several factors that increase the budget of construction. In Mozambique, the underlying causes related to this issue are not well understood. This study is a first attempt to determine the influence factors of cost and time overruns in this context. This research aims to find the influence factors that contribute to the occurrence of cost and time overruns, and to establish their criticality in Mozambican construction projects. A systematic literature review (SLR) was carried out in a methodic fashion to ensure it is scrutinizingly and repeatable. Relevant information was extracted from the selected articles and subsequently synthetized in order to categorize and identify the influence factors, which trigger time and cost overruns. The literature on time and cost overruns in construction is contrasting with 92 articles from 46 different reference sources. Most research has focused on the study of some of these factors in particular, while this research sought to classify and synthesize the factors in order to enable a new and more comprehensive view of this phenomenon. Nine categories were identified and defined on the basis of their determinants: (i) activities and equipments; (ii) management; (iii) design and documentation; (iv) financing; (v) environmental and economic; (vi) organization; (vii) contracts; (viii) scope changes and (ix) governmental relations. Moreover, 95 influencing factors were identified and classified accordingly. A survey has been designed to collect data from construction managers in Mozambique in 272 Mozambican constructions, seeking to find out the critical influence factors related to cost and time overruns. The results showed 20 relevant factors for the occurrence of cost and time overrun in Mozambican construction. With the basis of factors, guidelines were presented for reducing the impact that these factors cause for the enterprises that can be validated in future studies / Mestrado / Arquitetura e Construção / Mestra em Engenharia Civil