Optimisation of Bacillus thuringiensis var. israelensis (Vectobac) applications for the blackfly control programme on the Orange River, South Africa

The Orange River, South Africa’s largest river, is a critical water resource for the country. In spite of the clear economic benefits of regulating river flows through a series of impoundments, one of the significant undesirable ecological consequences of this regulation has been the regular outbreaks of the pest blackfly species Simulium chutteri and S. damnosum s.l. (Diptera: Simuliidae). The current control programme, carried out by the South African National Department of Agriculture, uses regular applications, by helicopter, of the target-specific bacterial larvicide Bacillus thuringiensis var. israelensis. While cost-benefit analyses show significant benefits to the control programme, benefits could potentially be further increased through applying smaller volumes of larvicide in an optimised manner, which incorporates upstream residual amounts of pesticide through downstream carry. Using an optimisation technique applied in the West African Onchocerciasis Control Programme, to a 136 km stretch of the Orange River which includes 31 blackfly breeding sites, we demonstrate that 28.5% less larvicide could be used to potentially achieve the same control of blackfly. This translates into potential annual savings of between R540 000 and R1 800 000. A comparison of larvicide volumes estimated using traditional vs. optimised approaches at different discharges, illustrates that the savings on optimisation decline linearly with increasing flow volumes. Larvicide applications at the lowest discharge considered (40 m³·s^-1) showed the greatest benefits from optimisations, with benefits remaining but decreasing to a theoretical 30% up to median flows of 100 m3·s-1. Given that almost 70% of flows in July are less than 100 m³·s^-1, we suggest that an optimised approach is appropriate for the Orange River Blackfly Control Programme, particularly for flow volumes of less than 100 m³·s^-1. We recommend that trials be undertaken over two reaches of the Orange River, one using the traditional approach, and another using the optimised approach, to test the efficacy of using optimised volumes of B.t.i.

Robust parallel filtering design of a swarm tracking system

Swarming networks of mobile autonomous agents require inter-agent position information in order perform various tasks. The primary control input for the majority of current control strategies is inter-agent distance information. In this paper we provide a robust parallel filter based tracking scheme that allows a mobile agent to track other multiple mobile agents. The distance, angle, and relative position is given in a direct target tracking output. This allows the mobile agent to decide which information is best suited for the particular objective

Sustaining dietary changes for preventing obesity and diabetes: lessons learned from the successes of other epidemic control programs

A degree of success has been achieved in controlling several epidemics of infectious and non-infectious causes of death in countries, such as, Australia and New Zealand. Using the epidemiological triad (host, vector, environment) as a model, the key components of the control of these epidemics have been identified and compared to the current status of interventions to prevent obesity and its main disease consequence, type 2 diabetes. Reductions in mortality from tobacco, cardiovascular diseases, road crashes, cervical cancer and sudden infant death syndrome have been achieved by addressing all corners of the triad. Similarly, prevention programs have minimized the mortality from HIV AIDS and melanoma mortality rates are no longer rising. The main lessons learned from these prevention programs that could be applied to the obesity/diabetes epidemic are: taking a more comprehensive approach by increasing the environmental (mainly policy-based) initiatives; increasing the 'dose' of interventions through greater investment in programs; exploring opportunities to further influence the energy density of manufactured foods (one of the main vectors for increased energy intake); developing and communicating specific, action messages; and developing a stronger advocacy voice so that there is greater professional, public and political support for action. Successes in the other epidemics have been achieved in the face of substantial barriers within individuals, society, the private sector and government. The barriers for preventing obesity/diabetes are no less formidable, but the strategies for surmounting them have been well tested in other epidemics.

Organizational change in the public sector: augmenting the demand control model to predict employee outcomes under New Public Management

This study identifies the environmental and personal characteristics that predict employee outcomes within an Australian public sector organization that had, under New Public Management (NPM), implemented a variety of practices traditionally found in the private sector. These are more results-oriented, and their adoption can be accompanied by increased strain for employees. The current investigation was guided by two complementary theories, the Demand Control Support (DCS) model and Conservation of Resources (COR) theory, and sought to examine the benefits of building on the DCS to include both situation-specific stressors and internal coping resources. Survey responses from 1,155 employees were analysed. The hierarchical regression analyses indicated that both external and employee-centred variables made significant contributions to variations in psychological health, job satisfaction, and organizational commitment. The external resources, work based support and, to a lesser extent, job control, predicted relatively large proportions of the variance in the target variables. The situation-specific stressors, particularly those involving harmful management practices (e.g., insufficient time to do job as well as you would like, lack of recognition for good work), made significant contributions to the outcome measures and generally supported the process of augmenting the generic components of the DCS with more situation-specific variables. In terms of internal resources, problem and emotion-based coping improved the capacity of the model to predict psychological health. The results suggest that the impact of NPM can be ameliorated by incorporating the dimensions of the augmented DCS and coping resources into the change programme.

Professional identity and the contemporary university: a culture of control, accountability and virtuality?

In recent years many changes to the funding and management of universities have taken place. In the current climate of academia in Australia professional academics find themselves immersed in the culture of the managed university that uses the rhetoric of commitment to flexible delivery to put in place systems designed to increase accountability, surveillance and control. At the same time some argue that the focus on research, quality teaching and effective pedagogy has lessened. The empirical research base for this paper has enabled me to better understand some of the emerging trends my university. It looks at how changes to the experience of being academic impact on the work of academics as the power relations of the university continuously reposition them, and how academics in turn display resistance technologies. Changes to the technologies of management/administration of the university have resulted in what some academics have described as a loss of valuing of their knowledge and expertise and which may be seen by some as a threat to their opportunities to conduct productive educational inquiry.

The potential for tobacco control to reduce PBS costs for smoking-related cardiovaccular disease

Objective: To estimate Pharmaceutical Benefits Scheme (PBS) subsidies for drugs to treat smoking-related cardiovascular disease (CVD) in 2001-02, and over the period of the government's Intergenerational Report (IGR), assuming current smoking prevalence rates and a 5% absolute reduction.

Design and setting: An Australian epidemiological study, using prescribing data, aetiological fraction methodology, and IGR trends.

Main outcome measures: Estimated smoking-related PBS subsidy costs in 2001-02 and predicted cumulative subsidies until 2041-42, under current and reduced smoking prevalence assumptions.

Results: The PBS costs of smoking-related CVD in 2001-02 were $126 million, 9.77% of the cost of drugs for CVD and 2.96% of total PBS subsidies. The cumulative difference in these costs over the 40-year period with a 5% drop in smoking prevalence was predicted to be $4.5 billion, a 17% reduction. The saving would be $1.14 billion discounting future costs at 5% per year.

Conclusions: Further investment in tobacco control interventions could curb the increasing cost of the PBS and contribute to government efforts to ensure the viability of Australia's healthcare-financing programs. The net present value of a campaign to reduce smoking prevalence was estimated at $1 billion, with an internal rate of return of 33%.

Client identification and money laundering control : perspectives on the Financial Intelligence Centre Act 38 of 2001

The Financial Intelligence Centre Act 38 of 2001 (FICA) compels certain persons and institutions (defined as "accountable institutions'') to identify and verify the identity of a new client before any transaction may be concluded or any business relationship is established.1 Accountable institutions are listed in schedule ¹ to FICA and include banks, brokers, financial advisers, insurance companies, attorneys and estate agents. This duty to identify new clients came into effect on 30 June 2003. However, FICA also requires a similar procedure to be followed in respect of all current clients. Current clients are those with whom an accountable institution had business relationships on 30 June 2003.² After 30 June 2004 an institution may not conclude a transaction in the course of its business relationship with an unidentified current client, until it has established and verified that client's identity as prescribed. An institution that concludes any transaction in contravention of this prohibition, commits an offence and is liable to a fine not exceeding R10 million or to imprisonment of up to 15 years.³

The majority of accountable institutions and their clients failed to meet the June 2004 current client identification deadline.4 This failure posed serious economic and legal risks. With a few days to spare, the minister of finance granted a partial and temporary exemption in respect of these requirements. This article explores the statutory scheme for identification and re-identification of clients and some of the practical problems that were encountered. The June 2004 exemptions from these requirements are also considered and proposals for law reform are made.

The discussion of the FICA identification scheme necessitates the following brief overview of the international and South African money laundering control framework.

1 s 21(1) of FICA.
2 s 21(2) of FICA. See also s 82(2)(b).
3 s 46(2) of FICA read with s 68(1) of FICA.

Phytophthora cinnamomi and Australia’s biodiversity : impacts, predictions and progress towards control

Phytophthora cinnamomi continues to cause devastating disease in Australian native vegetation and consequently the disease is listed by the Federal Government as a process that is threatening Australia’s biodiversity. Although several advances have been made in our understanding of how this soil-borne pathogen interacts with plants and of how we may tackle it in natural systems, our ability to control the disease is limited. The pathogen occurs widely across Australia but the severity of its impact is most evident within ecological communities of the south-west and south-east of the country. A regional impact summary for all states and territories shows the pathogen to be the cause of serious disease in numerous species, a significant number of which are rare and threatened. Many genera of endemic taxa have a high proportion of susceptible species including the iconic genera Banksia, Epacris and Xanthorrhoea. Long-term studies in Victoria have shown limited but probably unsustainable recovery of susceptible vegetation, given current management practices. Management of the disease in conservation reserves is reliant on hygiene, the use of chemicals and restriction of access, and has had only limited effectiveness and not provided complete control. The deleterious impacts of the disease on faunal habitat are reasonably well documented and demonstrate loss of individual animal species and changes in population structure and species abundance. Few plant species are known to be resistant to P. cinnamomi; however, investigations over several years have discovered the mechanisms by which some plants are able to survive infection, including the activation of defence-related genes and signalling pathways, the reinforcement of cell walls and accumulation of toxic metabolites. Manipulation of resistance and resistance-related mechanisms may provide avenues for protection against disease in otherwise susceptible species. Despite the advances made in Phytophthora research in Australia during the past 40 years, there is still much to be done to give land managers the resources to combat this disease. Recent State and Federal initiatives offer the prospect of a growing and broader awareness of the disease and its associated impacts. However, awareness must be translated into action as time is running out for the large number of susceptible, and potentially susceptible, species within vulnerable Australian ecological communities.

Haptic control methodologies for telerobotic stair traversal

Teleoperated mobile robots provide the ability for a human operator to safely explore and evaluate hazardous environments. This ability represents an important progression towards the preservation of human safety in the inevitable response to situations such as terrorist activities and urban search and rescue. The benefits of removing physical human presence from such environments are obvious, however challenges inhibiting task performance when remotely operating a mobile robotic system need to be addressed. The removal of physical human presence from the target environment introduces telepresence as a vital consideration in achieving the desired objective. Introducing haptic human-robotic interaction represents one approach towards improving operator performance in such a scenario. Teleoperative stair traversal proves to be a challenging task when undertaking threat response in an urban environment. This article investigates the teleoperation of an articulated track mobile robot designed for traversing stairs in a threat response scenario. Utilising a haptic medium for bilateral human-robotic interaction, the haptic cone methodology is introduced with the aim of providing the operator with a vision-independent, intuitive indication of the current commanded robot velocity. The haptic cone methodology operates synergistically with the introduced fuzzy-haptic augmentation for improving teleoperator performance in the stair traversal scenario.

3D virtual haptic cone for intuitive vehicle motion control

Haptic technology provides the ability for a system to recreate the sense of touch to a human operator, and as such offers wide reaching advantages. The ability to interact with the human's tactual modality introduces haptic human-machine interaction to replace or augment existing mediums such as visual and audible information. A distinct advantage of haptic human-machine interaction is the intrinsic bilateral nature, where information can be communicated in both directions simultaneously. This paper investigates the bilateral nature of the haptic interface in controlling the motion of a remote (or virtual) vehicle and presents the ability to provide an additional dimension of haptic information to the user over existing approaches [1-4]. The 3D virtual haptic cone offers the ability to not only provide the user with relevant haptic augmentation pertaining to the task at hand, as do existing approaches, however, to also simultaneously provide an intuitive indication of the current velocities being commanded.

Social control, self-control and psychosocial problems in adolescent males

‘Psychosocial problems’ are psychological problems that are regarded as resulting from the interaction between the adaptive capacities of individuals and the demands of their physical and social environments. Many different factors have been theoretically proposed, and empirically established, as predictors of a range of psychosocial problems in adolescents. However, a problem exists in that this literature appears to lack an integrative framework that has validity across the range of problems that are observed. The purpose of the current research is to propose and test a model that draws together three clusters of factors that are useful in predicting the incidence of adolescent psychosocial problems. These are family structural background factors, family functioning variables and control beliefs. Data were collected from 155 adolescent males aged between 12 and 19 by a single concurrent and retrospective self-report questionnaire. This included data about the respondent (age, involvements with mental health or juvenile justice agencies) and family structural background factors (days per week worked by mother/father, occupational status for mother/father, residential mobility, number of persons in the family home). The questionnaire also incorporated the Parental Bonding Instrument (Parker, Tupling & Brown, 1979) to quantify the levels of perceived parental care and overprotection, and an adaptation of the Parental Discipline Style Scale (Shaw & Scott, 1991), to assess punitive, love withdrawing and inductive discipline practices. In addition, the (Low) Self-control Scale (Grasmick, Tittle, Bursick & Arneklev, 1993) and the Locus of Control of Behaviour Scale (Craig, Franklin, & Andrews, 1984) were used to collect data concerning adolescents’ perceived behavioural self-control and locus of control. Finally, selected sub-scales of the Child Behavior Checklist Youth Self-Report (Achenbach, 1991b) were used to collect data on the incidence of social withdrawal, somatisation, anxiety and depression, aggression and delinquency among the respondents, and in aggregated form, the incidence of ‘total problems’ and internalising and externalising behaviours. Results indicated family structural background factors, family functioning variables and control beliefs possess limited predicted validity and that the usefulness of the proposed model varies between specific psychosocial problems. Family functioning variables were generally stronger predictors than family structural background factors, particularly for internalising behaviours. Of these, levels of parental care and overprotection were generally the strongest predictors. Perceived self-control and locus of control were also generally strong predictors, but were particularly powerful with respect to externalising behaviours. The strength of predictive relationships was observed to vary between specific internalising and externalising behaviours, suggesting that individual difference variables not assessed in the current research were differentially influential. Finally, the parental and individual characteristics that predicted maximal levels of adjustment (defined in terms of minimal levels of internalising and externalising behaviours) were explored and the correlates of various parenting style typologies (Parker et al., 1979) were investigated. These results strongly confirmed the importance of family functioning and control beliefs with respect to the prediction of internalising, externalising and well-adjusted behaviours. In all analyses, substantial proportions of the variance in the incidence of problem behaviours remain unexplained. The findings are examined in relation to previous research focused on (familial) social control and (individual) self-control with respect to psychosocial problems in adolescents. In addition, methodological considerations are discussed and the implications of the findings for clinical and community interventions to address problem behaviours, and for further study, are explored.

Intersection of autonomy and social control : negotiating teenage motherhood

Contrary to popular belief, teenage mothers are a declining proportion of birthing women; however they receive much negative public attention. Of particular public concern is the high cost of supporting teenage mothers, in terms of financial, health and welfare resources. Historically, the typical founding mother of white Australia was single, but post-war changes in the family structure incorporated the expectation that children be born into two-parent households with the male as the breadwinner. Policy changes in the seventies saw the introduction of the Sole Parents Pension which meant that many birthing teenage women could choose to keep their infants rather than have a clandestine adoption or an enforced marriage. The parenting practices of teenage mothers have been criticised for being less than optimal, and mother and child are reported as being disadvantaged cognitively, psychosocially, and educationally. One widespread nursing service which provides support for new mothers in Victoria is the Maternal and Child Health Service; however, teenage mothers appear reluctant to use such services. Why this should be so became an important question for this research, since little is known about the parenting practices of teenage mothers. This study therefore sought to explore mothering from the perspective of five sole supporting teenage mothers each of whom had a child over six months of age. The research methodology took an interpretive ethnographic approach and was guided by feminist principles. The data were collected through repeated interviewing, participant observation, informal discussions with key informants, field notes and journalling. Data analysis was aided by the use of the software, program NUD-IST. It was found that the young women in this study each chose to give birth with full realisation that their existence was dependent on the Welfare State. Unanticipated, however, were the many structural barriers which made their lives cataclysmic, but these reinforced their determination to prove themselves worthy and capable mothers. The young women negotiated motherhood through a range of social supports and through maternal practice. Unquestionably, their social dependency on the welfare system forced them into marginal citizen status. Moreover, absolute and intrinsic poverty levels were experienced, brought about by inadequate welfare payments. Formal support agencies, such as the Maternal and Child Health nurses were rarely approached to provide childrearing support beyond the initial months following birthing, since the teenagers' basic needs such as shelter, food and clothing took precedence over their parenting needs. Additionally, some nurses were perceived to hold judgmental attitudes towards teenage mothers. It was far easier to forestall confrontation with nurses and the other 'older' women clientele by avoiding them. Thus XI they turned to charitable agencies who provided a safety net in the form of emergency supplies of money, food, or equipment. Informal networks of friends provided alternative modes of support when family help failed to materialise. The children, however, provided the young women with an opportunity to transform their lives by breaking free of the past, and by creating a new, mature existence for themselves. Despite being abandoned by family, friends, lovers and society, in the privacy and isolation of their own homes, they attempted to provide a more nurturing environment for their children than they themselves had received. Each bestowed unconditional maternal love on the child and were rewarded through the pleasures of watching their children grow and develop into worthwhile individuals. The children became the focus of their attention and their reason for living. In the course of their welfare dependency, the young women became public property, targets of surveillance, and were subjected to stigmatising and condescending public attitudes wherever they went. In this way, it was evident that they were an oppressed group, but each found ways of resisting. Rather than focussing on their oppressive or disabling lives, or dwelling on their disadvantaged status, the young women sought their identities as mature women through motherhood and by demonstrating that they could do this important job well. Through motherhood their lives had meaning and a sense of purpose. The thesis concludes that motherhood in the teenage years is difficult. However, if appropriate supports are made available, teenage mothers need be no different from non-teenage mothers. But with state resources shrinking, and their own resources limited, teenage mothers are disadvantaged. In some ways, this study showed that all levels of support were inadequate, although those provided through the charitable organizations were seen to be the most appropriate. This reflects the current policy of economic rationalism adopted by most Western liberal democracies in the 1980s and 1990s and no less by the former Keating Labor Government in Australia.

Control of ovarian development in the yabby (Cherax destructor)

A study under controlled conditions of ovarian development and rematuration in the yabby (Cherax destructot) was undertaken. The purpose of the study was to improve fundamental understanding of the reproductive biology of the species and provide a basis for application to hatchery management in culture. A review was made of the current status of yabby culture in Australia and the present understanding of reproductive biology of decapod Crustacea. The review emphasised factors controlling several aspects of ovarian development, in particular the processes of vitellogenesis. The subsequent study was designed within the context of current hatchery practice and was based on existing knowledge of decapod reproduction, The sexual differentiation of the yabby after hatching was investigated by serial histological sections, and experiments were carried out to investigate the possibility of sex reversal of males. Most of this Investigation was concerned with removing the influence of the androgenic gland in directing male development, with the intent of observing the development of the elementary gonadal tissue into ovary. It was found that in contrast to other crustacean species, the sex of the yabby becomes fixed before the development of external secondary sexual characteristics, and before the androgenic gland can be discerned. Ovarian tissue developed in females at less than 8 weeks after hatching. A preliminary examination was undertaken for feminising parasites in gonadal tissue of a hermaphrodite yabby. Investigation of the ovary after spawning demonstrated that whilst the female was held under constant conditions of temperature and photoperiod, little rematuration occurred. Except for generation of previtellogenic oocytes during the first two days, the gonaciosomatic index remained low for up to 5 months after spawning. If the temperature of the female was reduced to 10°C and maintained constant, the previtellogenic oocytes were partially resorbed over a three week period. Rematuration then commenced, albeit at a low rate because of the reduced temperature, A method for standardising gonadosomatic indices was developed which took into account differences in hepatopancreatic nutrient reserves of individuals and loss of one or more appendages. This part of the study also considered constraints to rematuration and developed a method of accounting for differences in the ability of females to remature after spawning. Experiments were carried out to investigate the effect of crowding and temperature manipulation on initiating ovarian rematuration and to determine the rate of rematuration at 22°C once initiated. The duration of low temperature had no effect on rematuration; an overnight cooling was sufficient to initiate the process, Rematuration to the end of stage 2 vltellogenesis was substantially complete within 10 days. Crowding of females suppressed rematuration, but less than ideal water quality was not found to have any effect. The presence of a male initiated rematuration at a similar rate, but also led to stage 3 vitetlogenesis and spawning. A study was made of the pheromonal influence of the male through water borne factors without success. Rematuration could not be induced in ovigerous females. The literature review indicated that ovarian rematuration was under the control of an ovary stimulating hormone produced by the thoracic nerve ganglia. Attempts were therefore made to stimulate ovarian rematuration by incorporating the thoracic nerve into the diet of females. Attempts were also made to induce the release of ovary stimulating hormone from the thoracic nerve with 5-hydroxytryptamine, and also with octopamine. No effects were found, but a significant difference between the neurophysiology of the yabby and northern hemisphere crayfish was observed, and the implications of this finding are discussed. The study did not produce any conclusive evidence of an ovary stimulating hormone for the yabby. A model of ovarian rematuration which collects the findings of the experimental investigations was developed, and was used to suggest a hatchery broodstock management protocol. This model differs from existing models in that rematuration triggers and nutritional status are considered.

Physical activity beliefs and behaviours among adults attempting weight control

Objective: To compare the frequency and duration of varying intensities of physical activity performed by adults trying to lose weight, avoid gaining weight and not actively trying to control their weight, and to compare these groups' beliefs about the physical activity they should perform.

Method: Random postal survey of 2500 Victorian adults selected from the Australian electoral roll (response rate=42%).

Measures: One-week physical activity recall (frequency and duration of walking, other moderate activity and vigorous activity), BMI (based on self-reported height and weight) and weight-control behaviour.

Results: At the time of the survey, 27% of respondents were actively trying to avoid gaining weight, 23.9% trying to lose weight and 49.1% undertaking no weight control. Respondents spent a mean time of 4.0 (±7.1) h walking, 5.5 (±7.9) h in moderate activity and 3.1(±5.9) h in vigorous activity during the week prior to the survey. Women trying to lose weight or avoid gaining weight engaged in vigorous activity more often than women not trying to control their weight. After adjusting for age, education and BMI, women trying to avoid gaining weight were 2.4 times more likely, and women trying to lose weight 2.5 times more likely, to have met current physical activity guidelines than women undertaking no weight control. On average, respondents believed they should spend 5.2 (±6.9) h walking, 6.5 (±8.2) h in moderate activity and 4.3 (±6.5) h in vigorous activity each week. Women trying to lose weight felt they should perform vigorous activity more often than other women. Weight-control behaviour was not associated with physical activity beliefs and behaviours of men.

Conclusion: Walking is a common activity among adults attempting weight control. However, many men and women do not fully recognize the value of moderate-intensity physical activity. Future efforts should be directed at promoting the role of moderate-intensity activity in weight control, particularly activity that can be performed outside of planned activity sessions.