An outbreak of salmonellosis linked to a marine turtle

In September 1998, an outbreak of gastroenteritis occurred in a coastal Aboriginal community in the Northern Territory over a seven day period. An investigation was conducted by the Center for Disease Control, Territory Health Services. Thirty-six cases were detected and 17% (n=6) were hospitalized. Salmonella chester was isolated from eight of nine stool specimens. Sixty-two percent of cases interviewed (n=28) reported consumption of a green turtle (Chelonia mydas) within a median of 24 hours prior to onset of illness. Of the remainder, all but two were contacts of other cases. Salmonella chester was isolated from a section of partially cooked turtle meat. There are no previous published reports of salmonellosis associated with consumption of sea turtles despite them being a popular food source in coastal communities in the Pacific.

An outbreak of salmonellosis linked to a marine turtle

On 18 September 1998 the Centre for Disease Control (CDC), Darwin was notified of an outbreak of gastroenteritis predominantly affecting adults in a Top End coastal community. There had been no previous presentations to the community clinic in the month of September with vomiting or diarrhoea. On 14 September, a green turtle (Chledonia mydas) was cooked and distributed throughout the community. Water collected from a water hole near the community (known as the aerator) was used as drinking water at the cook site and to cook the meat. In addition, there were reports that kava, a plant derived tranquilliser,1 had been consumed the night before using water from the same source. An investigation was conducted to determine the aetiology and source and to instigate prevention and control measures.

Graphene ripples generated by grain boundaries in highly ordered pyrolytic graphite

Atomic scale periodic ripples that extend for several nanometers on the surface of adjacent graphitic grains have been observed for the first time on highly ordered pyrolitic graphite by UHV-STM. The ripples emanate from a grain boundary, and are explained in terms of a mechanical deformation due to the elastic strain accumulated along the GB, which is relieved out-of-plane in the topmost graphene layer. We present a molecular dynamics model that accounts for the formation of similar ripples as result of the lattice mismatch induced by two different grain orientations.

The impact of organizational boundaries on (re)building capabilities

The literature concerning firm boundaries has focussed extensively on the rationale for different boundary choices and the economic efficiencies that such choices can make. There is also an acknowledged position that a firm’s boundary choices may impact the ability of a firm to maintain and even build new capabilities, though such choices may not be optimal from an economic efficiency perspective. It is in this context that we seek to investigate how firms make this potential trade-off in respect of their boundary choices and how these choices are implemented across a wide range of activities. Using qualitative data from three public sector construction oriented organizations, we observe that neither pure make nor buy decisions assisted significantly in capability building. Dual modes – where firms make and buy the same product or service simultaneously – provided firms with some opportunities to manage this paradox, but the most successful decisions seemed to occur in respect of using intermediate governance modes such as alliances. We also observed that the boundary choice was just one dimension of the capability building process and firms pursuing the same boundary choice decisions often had quite divergent outcomes on the basis of their boundary management and the ability of knowledge to move across firm boundaries.

Conceptualising Women's Working Lives : Moving the Boundaries of Discourse

"Theoretical work on the career development of women has travelled a journey from critique to creation. Early work responded to and criticised a literature that focused on theorising male roles in a workplace that was conceptualised as providing vertical career paths primarily for middle class males. More recently theorists are creating new constructions and frameworks to enable a more holistic understanding of career, applicable to both women and men. These constructions include broadening the discussion from women’s careers to women’s working lives. This is the fifth book in the Sense Publishers Career Development Series. It features the vibrant work of contributors from around the world writing in the field of women’s working lives. It emphasises the need to explore theoretical connections and understandings in order to facilitate a more holistic and inclusive understanding of women’s working lives. The writers in the current volume acknowledge the changing roles of women, in both public and private spheres. Women’s roles in paid work are changing both in their nature and type of engagement. In addition, with an ageing population, women’s roles in care work are increasingly being extended from child care to aged care. This book provides a history of theorising about women's careers, in addition to presenting a focus on current empirical and theoretical work which contributes to understandings of women's working lives. It’s contributions both map the current discourse and challenge future work to extend the boundaries of that discourse."--publisher website

Taxonomic analysis of marine phytoplankton

Samples of sea water contain phytoplankton taxa in varying amounts, and marine scientists are interested in the relative abundance of each taxa. Their relative biomass can be ascertained indirectly by measuring the quantity of various pigments using high performance liquid chromatography. However, the conversion from pigment to taxa is mathematically non trivial as it is a positive matrix factorisation problem where both matrices are unknown beyond the level of initial estimates. The prior information on the pigment to taxa conversion matrix is used to give the problem a unique solution. An iteration of two non-negative least squares algorithms gives satisfactory results. Some sample analysis of data indicates prospects for this type of analysis. An alternative more computationally intensive approach using Bayesian methods is discussed.

Constrained control design for dynamic positioning of marine vehicles with control allocation

In this paper, we address the control design problem of positioning of over-actuated marine vehicles with control allocation. The proposed design is based on a combined position and velocity loops in a multi-variable anti-windup implementation together with a control allocation mapping. The vehicle modelling is considered with appropriate simplifications related to low-speed manoeuvring hydrodynamics and vehicle symmetry. The control design is considered together with a control allocation mapping. We derive analytical tuning rules based on requirements of closed-loop stability and performance. The anti- windup implementation of the controller is obtained by mapping the actuator-force constraint set into a constraint set for the generalized forces. This approach ensures that actuation capacity is not violated by constraining the generalized control forces; thus, the control allocation is simplified since it can be formulated as an unconstrained problem. The mapping can also be modified on-line based on actuator availability to provide actuator-failure accommodation. We provide a proof of the closed-loop stability and illustrate the performance using simulation scenarios for an open-frame underwater vehicle.

Marine aerosol hygroscopicity and volatility, measured on the Chatham Rise (New Zealand)

The Surface Ocean Aerosol Production (SOAP) study was undertaken in February/March 2012 in the biologically active waters of the Chatham Rise, NZ. Aerosol hygroscopicity and volatility were examined with a volatility hygroscopicity tandem differential mobility analyser. These observations confirm results from other hygroscopicity-based studies that the dominant fraction of the observed remote marine particles were non-sea salt sulfates. Further observations are required to clarify the influences of seawater composition, meteorology and analysis techniques seasonally across different ocean basins.

Building boundaries on boundary objects : a field study of a ubicomp tool in a design studio

In this paper, we provide the results of a field study of a Ubicomp system called CAM (Cooperative Artefact Memory) in a Product Design studio. CAM is a mobile-tagging based messaging system that allows designers to store relevant information onto their design artefacts in the form of messages, annotations and external web links. From our field study results, we observe that the use of CAM adds another shared ‘space’ onto these design artefacts – that are in their natural settings boundary objects themselves. In the paper, we provide several examples from the field illustrating how CAM helps in the design process.

Motion Control of Marine Craft

Marine craft (surface vessels, underwater vehicles, and offshore rigs) perform operations that require tight motion control. During the past three decades, there has been an increasing demand for higher accuracy and reliability of marinecraft motion control systems. Today, these control systems are an enabling factor for single and multicraft marine operations. This chapter provides an overview of the main characteristics and design aspects of motion control systems for marine craft. In particular, we discuss the architecture of the control system, the functionality of its main components, the characteristics of environmental disturbances, control objectives, and essential aspects of modeling and motion control design.

Pushing cultural competence boundaries in nutrition and dietetics training

A health workforce ready for safe practice is a government priority, and particularly critical to support indigenous communities closing ‘the gap’. Increased pressure exists on dietetic training programs for quality placements, with fewer opportunities for immersion in Aboriginal and Torres Strait Islander communities to demonstrate cultural competence. In 2012, Queensland University of Technology established a partnership with Apunipima Cape York Health Council with 56 weeks of dietetic placement for 8 students provided to achieve these aims. Clinical practice in Community Public Health Nutrition (CPHN) was structured in a standard 6 week placement, with Individual Case Management (ICM) and Foodservice Management (FSM) integrated across 8 weeks (4 each), with an additional 2 weeks ICM prior in a metropolitan indigenous health service. Students transitioned from urban to rural then remote sites, with new web-based technologies used for support. Strong learning opportunities were provided, with CPHN projects in antenatal and child health, FSM on standardisation of procedures in a 22 bed health facility, and ICM exposing students to a variety of cases via hospital in/outpatients, general clinics and remote community outreach. Supervisor focus group evaluation was positive, with CPHN and FSM enhancing capacity of service. Student focus group evaluation revealed placements exceeded expectations, with rating high, and strong confidence in cultural competence described. Students debriefed final and third year cohorts on their experiences, with increased awareness and enthusiasm for work with indigenous communities indicated by groups. With the success of this partnership, placements are continuing 2013, and new boundaries in dietetic training established.

Dynamic positioning of marine craft using a port-Hamiltonian framework

Dynamic positioning of marine craft refers to the use of the propulsion system to regulate the vessel position and heading. This type of motion control is commonly used in the offshore industry for surface vessels, and it is also used for some underwater vehicles. In this paper, we use a port-Hamiltonian framework to design a novel nonlinear set-point-regulation controller with integral action. The controller handles input saturation and guarantees internal stability, rejection of unknown constant disturbances, and (integral-)input-to-state stability.

Practical aspects of frequency-domain identification of dynamic models of marine structures from hydrodynamic data

The motion response of marine structures in waves can be studied using finite-dimensional linear-time-invariant approximating models. These models, obtained using system identification with data computed by hydrodynamic codes, find application in offshore training simulators, hardware-in-the-loop simulators for positioning control testing, and also in initial designs of wave-energy conversion devices. Different proposals have appeared in the literature to address the identification problem in both time and frequency domains, and recent work has highlighted the superiority of the frequency-domain methods. This paper summarises practical frequency-domain estimation algorithms that use constraints on model structure and parameters to refine the search of approximating parametric models. Practical issues associated with the identification are discussed, including the influence of radiation model accuracy in force-to-motion models, which are usually the ultimate modelling objective. The illustration examples in the paper are obtained using a freely available MATLAB toolbox developed by the authors, which implements the estimation algorithms described.