Different response to epidermal growth factor of hepatocytes in cultures isolated from male or female rat liver. Inhibitor effect of estrogen on binding and mitogenic effect of epidermal growth factor

Deoxyribonucleic acid (DNA) synthesis in hepatocytes isolated from the livers of male and female rats has been compared in monolayer culture. Plating efficiency, DNA and protein content, viability, and morphologic appearance were the same in cultures prepared with hepatocytes isolated from male or female rats. Epidermal growth factor (EGF)-induced DNA synthesis was significantly higher in hepatocytes from male rats than in hepatocytes from female rats. This was the case whether hepatocytes were isolated from normal or partially hepatectomized male or female rats. Hepatocytes isolated from regenerating liver synthesize more DNA than those isolated from normal liver in response to EGF. This increased response to EGF in hepatocytes derived from regenerating liver was relatively the same for male- and female-derived hepatocytes, but the magnitude of the response was considerably higher in male-derived hepatocytes. In contrast, in vivo DNA synthesis in the liver remnant after partial hepatectomy was similar in male and female rats if measured 24 h after the operation. A comparison of EGF binding to male- and female-derived hepatocytes maintained in primary culture indicated a lower number of high-affinity receptors for EGF in the female hepatocytes. The addition of estrogen to primary cultures of hepatocytes isolated from male rats inhibited EGF binding as well as EGF-induced DNA synthesis. Our studies show significant differences in DNA synthesis in response to EGF when male and female hepatocytes are compared in primary culture. The regenerative response after partial hepatectomy, on the other hand, was the same in male and female rats. Thus, our studies indicate that the sex of the donor rat is important when hepatocytes in culture are used for a variety of studies, such as hepatocyte metabolism, induction and control of DNA synthesis, and hepatocarcinogenesis. In addition, our results indicate that caution is advised when inferences are made from in vitro findings for in vivo conditions. © 1987

Perceptions: a critical factor in transformational change management – lessons from the Department of Correctional Services of South Africa

There is growing recognition globally that the current organisational change management methodologies and practices are ineffective. This admission is based on the fact that change efforts implemented in organisations do not produce the desired results in terms of set change objectives. This assertion is evidenced by the dismal success rate in the implementation of organisational change initiatives. Empirical studies conducted previously by authors such as Hattingh (2004), Balogun and Hope Hailey (2004), Bregman (2009), Lotich (2011), and Choi and Ruona (2011) have confirmed that there is indeed a high failure rate in the implementation of organisational change efforts. The high failure rate that organisations record is attributed to managers’ neglect of the elements and dynamics of change, which constitute the human dimension of change. People’s perceptions of change form part of the dynamics of change which need to be seriously addressed if success in the implementation of organisational change efforts is to be attained. Empirical studies that seek to validate the claim that perceptions play a critical role in shaping people’s attitudes towards change and consequently their responses to change in terms of their reactions and resistance to change, have somehow been very limited. This is what this study sought to do – to investigate, establish, explore and understand the role that perceptions play in influencing people’s attitudes towards change, thereby influencing the status of change in terms of success or failure. The undertaking of the study on perceptions was to ensure that managers understand the influence that perceptions have on people’s attitudes towards change. The researcher conducted a literature study in order to contextualise the role of perceptions in influencing people’s attitudes within the offender correctional environment in the Department of Correctional Services of South Africa. Two survey questionnaires, one for correctional officials and the other for offenders, were utilised for purposes of collecting data. The results of the study revealed that perceptions play a significant role in shaping people’s attitudes towards change and consequently their reactions to and experiences of change

Exploring the triggers of transformational change in the South African Department of Correctional Services

sChange is a critical phenomenon in any organisation that wants to optimise its performance at individual, team and organizational levels in order to survive and remain competitive in the intensely competitive and globalised operational environment – be it economic, social, political, technological, international or labour market environment. This paper presents empirical evidence gathered from research participants in the Correctional Centres located in the KwaZulu-Natal Region of the Department of Correctional Services on the factors that triggered the fundamental culture change from the punishment-oriented philosophy to the rehabilitation-driven philosophy in terms of the treatment of sentenced offenders (herein referred to as DCS change). An interest in the triggers of transformational change within a correctional environment has motivated the authors to embark on an empirical study which sought to establish the triggers of the transformational change in the Department of Correctional Services of South Africa. The study was significant, particularly if one considers the fact that there is generally an interest in the factors that force organisations to initiate and implement organisation-wide changes. Change and transformation strategists, organisation development practitioners, and managers in general in both the public and private sector globally and in South Africa in particular will benefit from the study, particular if one considers the fact that transformational change interventions are currently being implemented across the South African public service as part of the government’s agenda of reconstructing and developing the South African society. An extensive literature study on the external and internal triggers of organisational change was undertaken as part of contextualising the triggers of transformational change within the South African Correctional Services environment in general. The literature study was followed by the empirical study which focused on gathering data from correctional officials and offenders through utilising two survey questionnaires. The empirical findings revealed that the fundamental culture change from the punishment-oriented philosophy which was characterised by nonexistence of a human rights culture to a rehabilitation-focused philosophy underpinned by the promotion and maintenance of a human rights culture was sparked off by various internal and external factors. These ranged from financial, social and political reasons to complaints about service from offenders, complaints from national and international bodies regarding human rights violations, competitive forces, proactive and progressive leadership,and the need to reduce recidivism

Preliminary investigation into the cause of acid mine water induced seismicity in Johannesburg

A preliminary investigation was done into the possible causes of the increased seismic activity in the Witwatersrand Basin. The paper focuses on approximated underground mining areas, groundwater mobility, rock types and the proximity of fault lines to seismic events. These parameters were mapped and correlated with observed seismicity in the area. There is some indication that the presence of underground mining areas has a positive relationship with the occurrence of seismic events. The other parameters exhibit a negative relationship with seismic activity. However, more detailed investigations are required before final conclusions can be drawn. An approach to risk assessment of possible earthquake scenarios in the City of Johannesburg (CoJ) is proposed. The approach aims to assess potential damage to infrastructure and loss of life in the case of an earthquake. The results of such an assessment may provide justification for more detailed investigations

Skin Blood Perfusion and Oxygenation Colour Affect Perceived Human Health

Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice

Facial shape analysis identifies valid cues to aspects of physiological health in Caucasian, Asian and African populations

Facial cues contribute to attractiveness, including shape cues such as symmetry, averageness and sexual dimorphism. These cues may represent cues to objective aspects of physiological health, thereby conferring an evolutionary advantage to individuals who find them attractive. The link between facial cues and aspects of physiological health is therefore central to evolutionary explanations of attractiveness. Previously, studies linking facial cues to aspects of physiological health have been infrequent, have had mixed results, and have tended to focus on individual facial cues in isolation. Geometric morphometric methodology (GMM) allows a bottom-up approach to identifying shape correlates of aspects of physiological health. Here, we apply GMM to facial shape data, producing models that successfully predict aspects of physiological health in 272 Asian, African and Caucasian faces ? percentage body fat (21.0% of variance explained), body mass index (BMI; 31.9%) and blood pressure (BP; 21.3%). Models successfully predict percentage body fat and blood pressure even when controlling for BMI, suggesting that they are not simply measuring body size. Predicted values of BMI and BP, but not percentage body fat, correlate with health ratings. When asked to manipulate the shape of faces along the physiological health variable axes (as determined by the models), participants reduced predicted BMI, body fat and (marginally) BP, suggesting that facial shape provides a valid cue to aspects of physiological healthpublishersversionPeer reviewe

SCHOOLING BEHAVIOUR OF SARDINE SARDINOPS SAGAX IN FALSE BAY, SOUTH AFRICA

The schooling behaviour of sardine Sardinops sagax in False Bay on the south coast of South Africa was studied in October 1995 using high-resolution sonar and a hull-mounted, echo-integration unit. School formation and disintegration were studied, and school shape, packing density, swimming behaviour and inter- and intra-school event rates were quantified. Mean fish density was 29.5 fish m-3 (SD 46 fish m-3), but it varied between schools by a factor of about 100 (from 2 to 233 fish m-3). Tracked schools moved at average speeds of 0.67–1.59 m s-3. Schools changed shape on average every 2.08 minutes, and underwent either splits or merges with other schools on average every 5 minutes. Relationships between the geometric dimensions and biomass of the schools were established.Afr. J. mar. Sci. 25: 185–19

Labour epidural analgesia audit in a tertiary state hospital in South Africa

Background: Neuraxial analgesia is currently considered the most effective method of labour analgesia. While well studied in developed countries, it is uncertain whether the results, particularly regarding epidural analgesia complication rates, can be extrapolated to the context of the South African public hospital.Method: A retrospective one-year audit reviewed available records for indications for-, complications of-, and patient satisfaction with labour epidural analgesia at Tygerberg Hospital, Western Cape.Results: During the period audited, 157 (2.2%) of 7 005 parturients received labour epidural analgesia. One hundred and forty nine records were retrieved for analysis. Epidural analgesia was not provided on patient request. Rather, specific indications for epidural analgesia in 73.2% of these cases were preeclampsia, cardiovascular disease and morbid obesity. The incidence of complications was 32.3%, comprising hypotension (13.4%) and all other complications (18.9%). Most complications were minor and self-limiting (97.9%). One serious adverse event (cardiac arrest) due to accidental intravenous infusion of bupivacaine was recorded. Resuscitation with lipid emulsion was successful. Parturients reported being “happy” or “very happy” (50% and 36% respectively) with epidural analgesia.Conclusions: At this tertiary referral hospital in the Western Cape, only 2.2% of parturients received labour epidural analgesia, possibly because of personnel time constraints. Indications comprised predominantly preeclampsia, cardiovascular disease and morbid obesity. The incidence of complications from labour epidural analgesia was in line with that observed in developed countries. Most patients were happy with their analgesia. This audit identifies an urgent need for improvement of the labour epidural service at this institution.Keywords: analgesia, complications, epidural, labour indication

Mapping the informal public transport network in Kampala with smartphones : making sense of an organically evolved chaotic system in an emerging city in Sub-Saharan Africa

In cities in the emerging world, public transport networks are governed by a large number of agents, each with their own agendas, priorities, incentives and resources, interacting nonlinearly through complex feedback loops. The transport system in these cities have developed into a semi-chaotic self-organizing structure with seemingly unpredictable behaviour to an outside observer. This is due to user agent actions by passengers, independent determination of operating plans and practices by transport operators, and a managing authority exhibiting a lack of will (both political and institutional), to implement adequate control measures to provide regulation and management of these systems. Based on the problems that face transport systems in developing cities and public transport in particular, this paper reports on an attempt to understand the supply of public transport in the Kampala area in a novel manner. We describe a mapping approach using a custom-developed smartphone application which was used to quickly and accurately capture informal transport systems for analysis and study of urban mobility where no dependable data was currently available. Secondly, based on the data created by the study project, to provide insights into the routes, operations and characteristics of the minibus taxi network which convey the majority of Kampala?s travelers. Our hypothesis is that by understanding the network in geospatial terms, we will be able to create benefits for all role-players and improve the efficiency and effectiveness of the supply of public transport to more closely match the demand for public transport in an emerging world city.Paper presented at the 35th Annual Southern African Transport Conference 4-7 July 2016 "Transport ? a catalyst for socio-economic growth and development opportunities to improve quality of life", CSIR International Convention Centre, Pretoria, South Africa.The Minister of Transport, South AfricaTransportation Research Board of the US