Port Elizabeth Provincial Hospital

It is now widely accepted that global warming is occurring, yet its effects on the world's largest ecosystem, the marine pelagic realm, are largely unknown. We show that sea surface warming in the Northeast Atlantic is accompanied by increasing phytoplankton abundance in cooler regions and decreasing phytoplankton abundance in warmer regions. This impact propagates up the food web (bottom-up control) through copepod herbivores to zooplankton carnivores because of tight trophic coupling. Future warming is therefore likely to alter the spatial distribution of primary and secondary pelagic production, affecting ecosystem services and placing additional stress on already-depleted fish and mammal populations.

This study considers the impact that some organisational factors can have on a service firm’s ability to return dissatisfied customers to a state of satisfaction through service recovery. In other words, it investigates the potential impact organisational variables (modelled as antecedents) can have on the service recovery performance of frontline staff. It also assesses the impact that successful service recovery has on two outcome variables, namely, intentions to resign and job satisfaction. The results show that organisational commitment exerts a strong positive influence on the service recovery performance of frontline staff as does empowerment and rewarding them for service excellence. When frontline staff are performing service recovery effectively, they are less likely to resign and report higher levels of job satisfaction.

Photovoltaic (PV) modules are renowned for their reliability. However, some modules degrade or even fail when operating outdoors for extended periods. To reduce the degradation, and the number of failures, extensive research is needed on the performance of PV modules. The aim of this study was to establish a photovoltaic degradation and failure assessment procedure. This procedure should assess all parameters of PV modules to completely analyze any observed degradation or failure. In this paper some degradation modes of PV modules are discussed and a procedure used to assess these degradation modes is then presented. Results obtained by subjecting Copper Indium Diselenide (CIS), single and triple junction amorphous silicon (a-Si and a-SiGe), Edge-defined Film-fed Growth (EFG) silicon and mono-crystalline silicon (mono-Si) modules to the assessment procedure are presented and discussed. Results obtained indicate that the thin-film modules degrade by up to 50% in performance after an initial outdoor exposure of 130 kWh/m/sup 2/. Visual inspection revealed that both crystalline modules had cracked cells. The mismatch due to the cracked cell in the EFG-Si module, however, was limited by the interconnect busbars. This paper accentuates the importance of characterizing all module performance parameters in order to analyze observed degradation and failure modes.

The objective of this study was to investigate whether superior service quality and superior transaction-specific customer satisfaction will enhance loyalty (as measured by purchasing intentions) among patients in the private health care industry. The research design allowed an assessment of the relative impact of individual dimensions of service quality and transaction-specific customer satisfaction on two dependent variables, namely loyalty (as measured by intentions to repurchase) and customer satisfaction, the latter measured as ‘overall’ or cumulative satisfaction.The results reveal that the service quality dimensions Empathy of nursing staff and Assurance impact positively on both Loyalty and Cumulative satisfaction.The customer satisfaction dimensions Satisfaction with meals, Satisfaction with the nursing staff and Satisfaction with fees all impact positively on both Loyalty and Cumulative satisfaction.

In this study, successor-related factors that can influence the succession process in small and medium-sized family businesses are empirically investigated. This study was undertaken in South Africa among 2,458 owner-managers and successors in 1,038 family businesses. These respondents were identified via a snowball-sampling technique. A total of 332 usable questionnaires were returned. The dependent variable in this study, namely, the perceived success of the succession process, is measured by two underlying dimensions: satisfaction with the process and continued profitability of the business. The empirical results indicate that the successor-related factors that influence satisfaction with the process are, on the one hand, the willingness of the successor to take over and the relationship between the owner-manager and successor, on the other hand. The continued profitability of the business is influenced by the willingness of the successor to take over the business, the preparation level of the successor, and the relationship between the successor and owner-manager. The relationship between the owner-manager and successor is in turn influenced by the extent to which interpersonal relationships in the family can be described as harmonious. Based on these findings recommendations for successful succession are offered.

In a national prevalence study of multiple sclerosis (M.S.) in the Republic of South Africa based on census day 1960 there were 118 individuals with M.S. who were born in Northern Europe (United Kingdom and other parts of North and Central Europe) and who had emigrated to the Republic by 1960. Their prevalence rate was 49 per 100,000 immigrants in comparison with a prevalence of 11 per 100,000 among native-born English-speaking white South Africans.To study the possible effect of age at immigration it was necessary to relate the M.S. immigrants to the appropriate denominator-the population at risk according to age at immigration. The population at risk by age at immigration has been estimated by two methods in an indirect fashion with the assistance of the Bureau of Census (1960) and by surveys of the population at risk 1968-9. Both studies suggest that the risk of developing M.S. was reduced to less than a third of the expected risk among those who immigrated under the age of 15 or 16.This study is further evidence that M.S. is an acquired exogenous disease, the precise nature of which is still not certain but, according to present knowledge, has as its leading contender the class of slow, latent, or temperate viruses.

A general outlook of the changing face of chemical synthesis is provided in this article through recent applications of continuous flow processing in both industry and academia. The benefits, major challenges and limitations associated with the use of this mode of processing are also given due attention as an attempt to put into perspective the current position of continuous flow processing, either as an alternative or potential combinatory technology for batch processing.

Persistent poor service delivery will have a harmful impact on the survival and growth prospects of service firms. If service failures occur, the literature contends, there are tactics and strategies service firms can employ to return customers to a state of satisfaction. However, no attempt has as yet been made to assess how satisfied customers are after service firms have tried to recover from service failures. The purpose of this study is, first, to identify the dimensions of transaction-specific service recovery satisfaction by analyzing consumer expectations and, second, to develop a validated measuring instrument to measure satisfaction with transaction-specific service recovery based on those dimensions. The evidence of validity (convergent, discriminant, and nomological) and reliability reported here confirms the construct validity of the 17-item RECOVSAT instrument to measure satisfaction with transaction-specific service recovery.

As in other eutrophied estuaries and coastal embayments, persistent hypoxia now routinely develops during summer in the mesohaline portion of the Neuse River estuary (North Carolina, USA). In response to interannual differences in hydrography, summer 1997 exhibited much more intense and widespread hypoxia than summer 1998, permitting inferences about impacts of hypoxia on food web dynamics by comparing system changes across these two summers. The trophic structure of the Neuse estuary now resembles the generic pattern for a degraded temperate estuary with (1) intense planktonic algal blooms and similarly high production of free‐living bacteria, (2) trivial levels of abundance of rooted aquatic plants and benthic macroalgae, (3) depleted apex predators, and (4) functional extinction of the historically dominant benthic grazer, eastern oysters. Detailed carbon‐flow models, based on comprehensive field data, demonstrated large differences between the two summers in trophic transfers and system dynamics. Largely because of greater mortality of benthic invertebrates from more intense hypoxia, total biomass of heterotrophs declined over summer by 51% in 1997 as compared to only 17% in 1998. Because net primary production increased over summer and herbivory in this system is predominantly benthic, the fraction of primary production consumed by herbivores declined over summer by 35% in 1997 and 29% in 1998. Influx of juvenile fishes and their rapid growth in the estuarine nursery over summer led to increases in energy demand by demersal fishes of 380% and 507% in the successive summers. Thus, hypoxia‐enhanced diversion of energy flows into microbial pathways away from consumers and mass mortality of benthic invertebrates from bottom hypoxia occurred at the season of greatest demand by predatory fishes and crabs using the estuary as nursery. Average residence time of carbon in the ecosystem declined by 51% in 1997 and 29% in 1998. Total system throughput declined over summer 1997 while increasing in 1998, indicating the reduced capacity of the system to transfer carbon to higher trophic levels in the more hypoxic summer. Late‐summer trophic pathways were characterized by greater numbers of cycles, but flows became increasingly dominated by microbial loops rather than transfers to consumers. Ecosystem trophic efficiency was only ∼4%, lower than other estuaries similarly analyzed. System properties indicative of resiliency of system function including development capacity, ascendancy, and flow diversity declined over summer 1997, while increasing or declining less in 1998. Thus, intensification of hypoxia caused dramatic reduction in the ecosystem's ability to transfer energy to higher trophic levels and rendered the ecosystem potentially less resilient to other stressors.

The early pioneers of services marketing in Europe, especially the Nordic School, argued that service quality consists of two or three underlying dimensions. Lehtinen and Lehtinen [1985] referred to physical and interactive quality while Christian Grönroos [1984] identified a technical dimension, a functional dimension and the firm's image as a third dimension. In later years, Parasuraman, Zeithaml and Berry [1988] published empirical evidence from five service industries which suggested that five dimensions more appropriately capture the perceived service quality construct. This study uses an exploratory factor analysis approach to investigate the empirical factor structure of the SERVQUAL instrument developed by Parasuraman et al. [1988] to measure perceived service quality. Based on the results of five exploratory analyses performed on five SERVQUAL data sets, a model for SERVQUAL is proposed. It suggests that the SERVQUAL difference scores are measures of two factors termed ‘intrinsic’ and ‘extrinsic’ service quality. The model is then fitted to the SERVQUAL data obtained from five samples of clients who evaluated the services of five service industries or companies by means of confirmatory factor analysis. The results of this study provide empirical support for the European authors who, in the early 1980s, argued that service quality perceptions are largely determined by two (rather than five) dimensions.

The future health and productivity of South Africa's approximately 250 estuaries is dependent on two main factors: management and freshwater inputs. Both management and water allocation decisions involve trade-offs between conservation and various types of utilisation. In order to facilitate decision-making in both of these spheres, it is necessary to understand the relative conservation importance of different estuaries. This study devises a method for prioritising South African estuaries on the basis of conservation importance, and presents the results of a ranking based on the collation of existing data for all South African estuaries. Estuaries are scored in terms of their size, type and biogeographical zone, habitats and biota (plants, invertebrates, fish and birds). Thirtythree estuaries are currently under formal protection, but they are not representative of all estuarine biodiversity. We performed a complementarity analysis, incorporating data on abundance where available, to determine the minimum set of estuaries that includes all known species of plants, invertebrates, fishes and birds. In total, 32 estuaries were identified as 'required protected areas', including 10 which are already protected. An estuary's importance status (including 'required protected area' status) will influence the choice of management class and hence freshwater allocation under the country's new Water Act, and can be used to assist the development of a new management strategy for estuaries, which is currently underway. WaterSA Vol.28(2) 2002: 191-206

The effect of high (ambient) and low (shaded to 50% of ambient) light on microphytobenthic biofilm primary production, vertical migration and allocation of photoassimilated carbon into extracellular carbohydrates was investigated over the low tide emersion period at Sarilhos Pequenos on the Tagus estuary, Portugal, in July 2000. Carbon uptake ( 14 C measurements), electron transport (pulse-amplitude modulated [PAM]-fluorescence) and carbon allocation into extracellular carbohydrate fractions were measured. There was a decrease in the maximum rate of primary production (P max ) ( 14 C) over the emersion period (16 decreasing to 5 mg C m -2 h -1 at midday and the end of emersion, respectively) that was independent of the incident light and the light history to which the biofilms had been exposed. Primary production ( 14 C) did not correlate with measurements of in situ relative electron transport rate (rel.ETR), due in part to the light-induced migration of the cells away from the sediment surface during periods of high irradiance (photosynthetic photon flux density [PPFD] > 1200 mol m -2 s -1 ). Downward migration coincided with the light level at which P max ( 14 C) was reached, 750 mol m -2 s -1 , and with a point of inflexion on the rel.ETR versus PPFD curve. Above this light level rel.ETR was over-estimated due to migration of the cells into a lower light field in the sediment. Shading significantly increased the extracellular polymeric substance (EPS) production rate (from 0.4 to 1.0 mg C m -2 h -1 in ambient and shaded light, respectively) and percentage allocation of photoassimilates into EPS (from 4 1.0 to 18 3.5% of total production in ambient and shaded light, respectively). In contrast, percentage allocation of photoassimilates to low molecular weight extracellular carbohydrate was higher in the non-shaded treatments (35 4.5% compared with 13 3.8% in ambient and shaded treatments, respectively), probably due to photosynthetic 'overflow'. In non-shaded biofilms there was little or no increase in the concentration of all extracellular carbohydrate fractions until the last hour before tidal immersion. Results indicate that diel patterns in microphytobenthic primary production are not predictable solely from light data.

This paper demonstrates how the power form of the Species-Area Relationship (SAR) can be used to set conservation targets for land classes using biodiversity survey data. The log-transformation of the power model is a straight line; therefore, if one knows the average number of species recorded per survey site and can estimate the true species number present in the land class, using EstimateS software, it is possible to calculate the slope of the curve, or z-value. The z-value is the exponent in the power model and it can then be used to estimate the proportion of area required to represent a given proportion of species present in any land class. This application of the SAR is explored using phytosociological relevé data from South Africa's Succulent Karoo biome. We also provide suggestions for extrapolating the estimated z-values to other land classes within a bioregion that lack sufficient survey data, using the relationship between z-values and remotely determined landscape variables such as habitat diversity (topographic diversity) and geographic location (latitude and longitude). The SAR predicts that for most Succulent Karoo vegetation types a conservation target of 10% of the land area would not be sufficient to conserve the majority of species. We also demonstrate that not all land classes are equal from a plant biodiversity perspective, so applying one target to all land classes in a region will lead to significant gaps and inefficiencies in any reserve network based on this universal target.

An analysis of the results of the 1996 census reveals a general decline in urban racial segregation levels in South Africa since the end of legal apartheid in 1991. However, the trends are not uniform with Whites remaining both more segregated and less open to change than the other groups. Africans have become more integrated, but the majority are constrained in their choice of residential options by the general levels of poverty. Asian and Coloured people have witnessed the greatest changes, with significant declines in segregation levels in the majority of cities as they begin to return to the areas from which they were forcibly removed in the previous 40 years. However, segregation levels remain exceptionally high and rapid integration may require government intervention.

BACKGROUND: The incidence of tuberculous pericarditis has increased in Africa as a result of the human immunodeficiency virus (HIV) epidemic. However, the effect of HIV co-infection on clinical features and prognosis in tuberculous pericarditis is not well characterised. We have used baseline data of the Investigation of the Management of Pericarditis in Africa (IMPI Africa) registry to assess the impact of HIV co-infection on clinical presentation, diagnostic evaluation, and treatment of patients with suspected tuberculous pericarditis in sub-Saharan Africa. METHODS: Consecutive adult patients in 15 hospitals in three countries in sub-Saharan Africa were recruited on commencement of treatment for tuberculous pericarditis, following informed consent. We recorded demographic, clinical, diagnostic and therapeutic information at baseline, and have used the chi-square test and analysis of variance to assess probabilities of significant differences (in these variables) between groups defined by HIV status. RESULTS: A total of 185 patients were enrolled from 01 March 2004 to 31 October 2004, 147 (79.5%) of whom had effusive, 28 (15.1%) effusive-constrictive, and 10 (5.4%) constrictive or acute dry pericarditis. Seventy-four (40%) had clinical features of HIV infection. Patients with clinical HIV disease were more likely to present with dyspnoea (odds ratio [OR] 3.2, 95% confidence interval [CI] 1.4 to 7.4, P = 0.005) and electrocardiographic features of myopericarditis (OR 2.8, 95% CI 1.1 to 6.9, P = 0.03). In addition to electrocardiographic features of myopericarditis, a positive HIV serological status was associated with greater cardiomegaly (OR 3.89, 95% CI 1.34 to 11.32, P = 0.01) and haemodynamic instability (OR 9.68, 95% CI 2.09 to 44.80, P = 0.0008). However, stage of pericardial disease at diagnosis and use of diagnostic tests were not related to clinical HIV status. Similar results were obtained for serological HIV status. Most patients were treated on clinical grounds, with microbiological evidence of tuberculosis obtained in only 13 (7.0%) patients. Adjunctive corticosteroids were used in 109 (58.9%) patients, with patients having clinical HIV disease less likely to be put on them (OR 0.37, 95% CI 0.20 to 0.68). Seven patients were on antiretroviral drugs. CONCLUSION: Patients with suspected tuberculous pericarditis and HIV infection in Africa have greater evidence of myopericarditis, dyspnoea, and haemodynamic instability. These findings, if confirmed in other studies, may suggest more intensive management of the cardiac disease is warranted in patients with HIV-associated pericardial disease.

Modulation of microcystin production has been extensively studied in both batch and continuous cultures. Positive correlations with medium nitrogen, medium phosphorous, light intensity, inorganic carbon availability, and growth rate have been reported. Negative correlations have been reported between microcystin content and medium phosphorous. The only reported quantitative relationship between any variable and microcystin production was that of growth rate. Microcystis aeruginosa PCC7806 was therefore cultured under continuous culture conditions in a bubble-lift reactor at a growth rate of 0.01 h(-1) in modified BG11 (constant phosphate concentration of 0.195 mM and varying nitrate from 0.125 to 18 mM) and sampled at steady states for analysis of cell number, microcystin content, cellular N and P, residual medium nutrient concentration, and carbon fixation rate. Cellular microcystin quotas showed significant positive correlation with both nitrate uptake and cellular nitrogen content and were negatively correlated with carbon fixation rate, phosphate uptake, and cellular phosphorous. Thus, the ratio of nitrate uptake to phosphate uptake, cellular N to cellular P, and nitrate uptake to carbon fixation were positively correlated to cellular microcystin. Microcystin quotas increased 10-fold from the lowest to the highest steady-state values. Cellular microcystin content therefore is controlled to a significant extent by variables other than growth rate, as was previously reported, with nitrogen the most significant modulator. Batch culture in BG11 under identical conditions yielded increased microcystin when nitrogen uptake exceeded relative growth rate, confirming the importance of nitrogen uptake in the modulation of microcystin content for a specific growth rate.

Abstract This paper describes research methodologies for the investigation of the mechanism of vulcanization and discusses the reactivity of thiuram and dithiocarbamate chemicals. The combined knowledge is subsequently applied to thoroughly review the mechanism and chemistry of both thiuram- and dithiocarbamate-accelerated sulfur vulcanization. Integration of the original mechanistic ideas from the 1960s and the results obtained in the past three decades now have led to a more balanced appraisal of events during vulcanization. Questions have been answered, solutions for old problems are proposed, and remaining fields of endeavor are identified.

Viable spawns have been obtained in the laboratory from untreated prawn Penaeus indicus and from others which had one eyestalk ablated. Fecundity was shown to be dependent on spawning technique, female size and whether the spawner was wild or domestic. Using low aeration during spawning, domestic unablated female fecundity was significantly lower than it was for wild females, due to a concomitantly smaller ovary volume. During late premoult, mature ovaries are resorbed to ovarian Stage 1-2 and after ecdysis they redevelop. 52.1 O/O of spawnings occurred during early premoult, 44.4 O/o during intermoult, 3.5 O/O at premoult, while no spawns occurred during late premoult or early postmoult. Average egg numbers and hatch successes were higher for unablated females when compared with ablated females. Average spawns per moult cycle were 1.98 and 2.24, respectively. It was conservatively estimated that wild females spawn at least 7-9 times in a lifetime. There were twice the number of spawns with a black tank background as there were with a white one and the former yielded higher average egg numbers and hatch successes. General pigmentation, ovary, egg and nauplius colour was dependent on background colour. Moult-cycle duration was temperature dependent but generally shorter for ablated females. As female condition decreased, moult-cycle duration decreased accordingly for any given temperature. Spawning activity declined when the condition factor was less than 0.8. Both ablated and unablated spawning females > 39 g tended to decrease in mass and condition while females < 39 g continued to grow. Nutrition is probably the main contributory factor to this anomalous growth. Large females possibly have nutritional requirements different from females of less than 39 g. A viable F, generation of P. indicus has been reared.

Abstract. The interstitial system of sandy beaches is lacunar and has its dimensions defined by the sand granulometry. It can be described by features such as pore size, porosity, permeability, and water content. The most important process occurring in this system, water filtration, is driven by inputs of freshwater from groundwater discharge, and inputs of seawater by tides, wave run‐up, and subtidal wave pumping. Reflective beaches have seawater input effected mainly by waves; they filter large water volumes with short residence times. Dissipative beaches display the opposite patterns, slowly filtering small volumes input by tides. Flow patterns and their effects on interstitial climate are described. The water table of the beach moves in response to groundwater discharge, tides, and waves and influences erosion/accretion processes on the beach face: a high water table promotes erosion. A series of moisture zones can be recognised from the dry surface sand at upper tide levels, to permanently saturated sand below the low tide water table, namely: a stratum of dry sand, a stratum of retention, a stratum of resurgence, and stratum of saturation. Interstitial chemistry is briefly described in terms of salinity changes, organic loads, oxygen content, and nutrient cycling. It is concluded that the interstitial environment of sandy beaches spans a continuum between physically and chemically controlled extremes: the former condition occurs on coarse sand reflective beaches, which experience low organic inputs and high filtration rates of large water volumes — resulting in powerful hydrodynamic forces; the latter occurs on dissipative beaches of fine sand, which are subject to high organic inputs and low filtration volumes — resulting in stagnation and steep vertical chemical gradients. Many intermediate situations occur and these are more favourable to interstitial life than either of the extremes.

Abstract The degree of serotiny (i.e. the proportion of follicles remaining closed in each year's crop of cones since the last fire) was measured in Bank‐sia attenuata, B. menziesii and B. prionotes at five sites along a climatic gradient extending 500 km north of Perth, Western Australia. The decrease in annual rainfall and increase in average temperature along the gradient paralleled a decrease in plant height and an increase in the degree of serotiny of all species. Extreme serotiny was recorded in the scrub‐heath at the xeric end of the gradient whereas two species were essentially non‐serotinous in the low woodland at the most mesic site. It is concluded that degree of serotiny is related to the fire characteristics of the site which depend on plant height. In xeric scrub‐heath, the entire canopies of the Banksia spp. are consumed by fire which promotes massive release of seed. This facilitates recruitment in an otherwise unpredictable and unreliable seedbed. In mesic woodland, where cones rarely come into contact With flames, seeds are released spontaneously and site conditions are more conducive to recruitment in the inter‐fire period.