Prediction of age at menopause from assessment of ovarian reserve may be improved by using body mass index and smoking status

Objective: Menopause is the consequence of exhaustion of the ovarian follicular pool. AMH, an indirect hormonal marker of ovarian reserve, has been recently proposed as a predictor for age at menopause. Since BMI and smoking status are relevant independent factors associated with age at menopause we evaluated whether a model including all three of these variables could improve AMH-based prediction of age at menopause. Methods: In the present cohort study, participants were 375 eumenorrheic women aged 19–44 years and a sample of 2,635 Italian menopausal women. AMH values were obtained from the eumenorrheic women. Results: Regression analysis of the AMH data showed that a quadratic function of age provided a good description of these data plotted on a logarithmic scale, with a distribution of residual deviates that was not normal but showed significant leftskewness. Under the hypothesis that menopause can be predicted by AMH dropping below a critical threshold, a model predicting menopausal age was constructed from the AMH regression model and applied to the data on menopause. With the AMH threshold dependent on the covariates BMI and smoking status, the effects of these covariates were shown to be highly significant. Conclusions: In the present study we confirmed the good level of conformity between the distributions of observed and AMH-predicted ages at menopause, and showed that using BMI and smoking status as additional variables improves AMH-based prediction of age at menopause.

The determinants of demand for private health insurance under Medicare

Since the introduction of Medicare in 1984, the proportion of the Australian population with private health insurance has declined considerably. Insurance for health care consumption is compulsory for the public health sector but optional for the private health sector. In this paper, we explore a number of important issues in the demand for private health insurance in Australia. The socio-economic variables which influence demand are examined using a binary logic model. A number of simulations are performed to highlight the influence and relative importance of various characteristics such as age, income, health status and geographical location on demand. A number of important policy issues in the private health insurance market are highlighted. First, evidence is provided of adverse selection in the private health insurance pool, second, the notion of the wealthy uninsured is refuted, and finally it is confirmed that there are significant interstate differences in the demand for private health insurance.

Speaker diarization : "who spoke when"

Speaker diarization is the process of annotating an input audio with information that attributes temporal regions of the audio signal to their respective sources, which may include both speech and non-speech events. For speech regions, the diarization system also specifies the locations of speaker boundaries and assign relative speaker labels to each homogeneous segment of speech. In short, speaker diarization systems effectively answer the question of ‘who spoke when’. There are several important applications for speaker diarization technology, such as facilitating speaker indexing systems to allow users to directly access the relevant segments of interest within a given audio, and assisting with other downstream processes such as summarizing and parsing. When combined with automatic speech recognition (ASR) systems, the metadata extracted from a speaker diarization system can provide complementary information for ASR transcripts including the location of speaker turns and relative speaker segment labels, making the transcripts more readable. Speaker diarization output can also be used to localize the instances of specific speakers to pool data for model adaptation, which in turn boosts transcription accuracies. Speaker diarization therefore plays an important role as a preliminary step in automatic transcription of audio data. The aim of this work is to improve the usefulness and practicality of speaker diarization technology, through the reduction of diarization error rates. In particular, this research is focused on the segmentation and clustering stages within a diarization system. Although particular emphasis is placed on the broadcast news audio domain and systems developed throughout this work are also trained and tested on broadcast news data, the techniques proposed in this dissertation are also applicable to other domains including telephone conversations and meetings audio. Three main research themes were pursued: heuristic rules for speaker segmentation, modelling uncertainty in speaker model estimates, and modelling uncertainty in eigenvoice speaker modelling. The use of heuristic approaches for the speaker segmentation task was first investigated, with emphasis placed on minimizing missed boundary detections. A set of heuristic rules was proposed, to govern the detection and heuristic selection of candidate speaker segment boundaries. A second pass, using the same heuristic algorithm with a smaller window, was also proposed with the aim of improving detection of boundaries around short speaker segments. Compared to single threshold based methods, the proposed heuristic approach was shown to provide improved segmentation performance, leading to a reduction in the overall diarization error rate. Methods to model the uncertainty in speaker model estimates were developed, to address the difficulties associated with making segmentation and clustering decisions with limited data in the speaker segments. The Bayes factor, derived specifically for multivariate Gaussian speaker modelling, was introduced to account for the uncertainty of the speaker model estimates. The use of the Bayes factor also enabled the incorporation of prior information regarding the audio to aid segmentation and clustering decisions. The idea of modelling uncertainty in speaker model estimates was also extended to the eigenvoice speaker modelling framework for the speaker clustering task. Building on the application of Bayesian approaches to the speaker diarization problem, the proposed approach takes into account the uncertainty associated with the explicit estimation of the speaker factors. The proposed decision criteria, based on Bayesian theory, was shown to generally outperform their non- Bayesian counterparts.

Extremely cold and hot temperatures increase the risk of ischaemic heart disease mortality : epidemiological evidence from China

Objective: To examine the effects of extremely cold and hot temperatures on ischaemic heart disease (IHD) mortality in five cities (Beijing, Tianjin, Shanghai, Wuhan and Guangzhou) in China; and to examine the time relationships between cold and hot temperatures and IHD mortality for each city. Design: A negative binomial regression model combined with a distributed lag non-linear model was used to examine city-specific temperature effects on IHD mortality up to 20 lag days. A meta-analysis was used to pool the cold effects and hot effects across the five cities. Patients: 16 559 IHD deaths were monitored by a sentinel surveillance system in five cities during 2004–2008. Results: The relationships between temperature and IHD mortality were non-linear in all five cities. The minimum-mortality temperatures in northern cities were lower than in southern cities. In Beijing, Tianjin and Guangzhou, the effects of extremely cold temperatures were delayed, while Shanghai and Wuhan had immediate cold effects. The effects of extremely hot temperatures appeared immediately in all the cities except Wuhan. Meta-analysis showed that IHD mortality increased 48% at the 1st percentile of temperature (extremely cold temperature) compared with the 10th percentile, while IHD mortality increased 18% at the 99th percentile of temperature (extremely hot temperature) compared with the 90th percentile. Conclusions: Results indicate that both extremely cold and hot temperatures increase IHD mortality in China. Each city has its characteristics of heat effects on IHD mortality. The policy for response to climate change should consider local climate–IHD mortality relationships.

Advice to consult a general medical practitioner in Western Australia : Could it be cancer?

Background: Many people will consult a medical practitioner about lower bowel symptoms, and the demand for access to general practitioners (GPs) is growing. We do not know if people recognise the symptoms of lower bowel cancer when advising others about the need to consult a doctor. A structured vignette survey was conducted in Western Australia. Method: Participants were recruited from the waiting rooms at five general practices. Respondents were invited to complete self-administered questionnaires containing nine vignettes chosen at random from a pool of 64 based on six clinical variables. Twenty-seven vignettes described high-risk bowel cancer scenarios. Respondents were asked if they would recommend a medical consultation for the case described and whether they believed the scenario was a cancer presentation. Logistic regression was used to estimate the independent effects of each variable on the respondent's judgement. Two-hundred and sixty-eight completed responses were collected over eight weeks. Results: The majority (61%) of respondents were female, aged 40 years and older. A history of rectal bleeding, six weeks of symptoms, and weight loss independently increased the odds of recommending a consultation with a medical practitioner by a factor of 7.64, 4.11 and 1.86, respectively. Most cases that were identified as cancer (75.2%) would not be classified as such on current research evidence. Factors that predict recognition of cancer presentations include rectal bleeding, weight loss and diarrhoea.

Communication and the casualisation of nursing : a critical ethnography

The contemporary working environment is being rapidly reshaped by technological, industrial and political forces. Increased global competitiveness and an emphasis on productivity have led to the appearance of alternative methods of employment, such as part-time, casual and itinerant work, allowing greater flexibility. This allows for the development of a core permanent staff and the simultaneous utilisation of casual staff according to business needs. Flexible workers across industries are generally referred to as the non-standard workforce and full-time permanent workers as the standard workforce. Even though labour flexibility favours the employer, increased opportunity for flexible work has been embraced by women for many reasons, including the gender struggle for greater economic independence and social equality. Consequently, the largely female nursing industry, both nationally and internationally, has been caught up in this wave of change. This ageing workforce has been at the forefront of the push for flexibility with recent figures showing almost half the nursing workforce is employed in non-standard capacity. In part, this has allowed women to fulfil caring roles outside their work, to ease off nearing retirement and to supplement the family income. More significantly, however, flexibility has developed as an economic management initiative, as a strategy for cost constraint. The result has been the development of a dual workforce and as suggested by Pocock, Buchanan and Campbell (2004), associated deep-seated resentment and the marginalisation of part-time and casual workers by their full-time colleagues and managers. Additionally, as nursing currently faces serious recruitment and retention problems there is urgent need to understand the factors which are underlying present discontent in the nursing profession. There is an identified gap in nursing knowledge surrounding the issues relating to recruitment and retention. Communication involves speaking, listening, reading and writing and is an interactive process which is central to the lives of humans. Workplace communication refers to human interaction, information technology, and multimedia and print. It is the means to relationship building between workers, management, and their external environment and is critical to organisational effectiveness. Communication and language are integral to nursing performance (Hall, 2005), in twenty-four hour service however increasing fragmentation due to part-time and casual work in the nursing industry means that effective communication management has become increasingly difficult. More broadly it is known that disruption to communication systems impacts negatively on consumer outcomes. Because of this gap in understanding how nurses view their contemporary nursing world, an interpretative ethnographic study which progressed to a critical ethnographic study, based on the conceptual framework of constructionism and interpretativism was used. The study site was a division within an acute health care facility, and the relationship between increasing casualisation of the nursing workforce and the experiences of communication of standard and non-standard nurses was explored. For this study, full-time standard nurses were those employed to work in a specific unit for forty hours per week. Non-standard nurses were those employed part-time in specific units or those nurses employed to work as relief pool nurses for shift short falls where needed. Nurses employed by external agencies, but required to fill in for shifts at the facility were excluded from this research. This study involved an analysis of observational, interview and focus group data of standard and non-standard nurses within this facility. Three analytical findings - the organisation of nursing work; constructing the casual nurse as other; and the function of space, situate communication within a broader discussion about non-standard work and organisational culture. The study results suggest that a significant culture of marginalisation exists for nurses who work in a non-standard capacity and that this affects communication for nurses and has implications for the quality of patient care. The discussion draws on the seven elements of marginalisation described by Hall, Stephen and Melius (1994). The arguments propose that these elements underpin a culture which supports remnants of the historically gendered stereotype "the good nurse" and these cultural values contribute to practices and behaviour which marginalise all nurses, particularly those who work less than full-time. Gender inequality is argued to be at the heart of marginalising practices because of long standing subordination of nurses by the powerful medical profession, paralleling historical subordination of women in society. This has denied nurses adequate representation and voice in decision making. The new knowledge emanating from this study extends current knowledge of factors surrounding recruitment and retention and as such contributes to an understanding of the current and complex nursing environment.

Perceptions and expectations for learning and development for older workers within Queensland local government councils : a case study

Current literature warns organisations about a global ageing phenomenon. Workplace ageing is causing a diminishing work pool which has consequences for a sustainable workforce in the future. This phenomenon continues to impact on local government councils in Australia. Australia has one of the world’s most rapidly ageing populations, and there is evidence that Australian local government councils are already resulting in an unsustainable workforce. Consequently, this research program investigated the role of older workers in the Queensland local government workplace in enabling them to extend their working lives towards transitional employment and a sustainable workforce in the future. Transitional Employment is intended as a strategy for enabling individuals to have greater control over their employment options and their employability during the period leading to their final exit from the workforce. There was no evidence of corporate support for older workers in Queensland local government councils other than tokenistic government campaigns encouraging organisations to "better value their older workers". (Queensland Government, 2007d, p.6). TE is investigated as a possible intervention for older workers in the future. The international and national literature review reflected a range of matters impacting on current older workers in the workforce and barriers preventing them from accessing services towards extending their employment beyond the traditional retirement age (60 years) as defined by the Australian Government; an age when individuals can access their superannuation. Learning and development services were identified as one of those barriers. There was little evidence of investment in or consistent approaches to supporting older workers by organisations. Learning and development services appeared at best to be ad hoc, reactive to corporate productivity and outputs with little recognition of the ageing phenomenon (OECD, 2006, p.23) and looming skills and labour shortages (ALGA, 2006, p. 19). Themes from the literature review led to the establishment of three key research questions: 1. What are the current local government workforce issues impacting on skills and labour retention? 2. What are perceptions about the current workplace environment? And, 3. What are the expectations about learning and development towards extending employability of older workers within the local government sector? The research questions were explored by utilising three qualitative empirical studies, using some numerical data for reporting and comparative analysis. Empirical Study One investigated common themes for accessing transitional employment and comprised two phases. A literature review and Study One data analysis enabled the construction of an initial Transitional Employment Model which includes most frequent themes. Empirical Study Two comprised focus groups to further consider those themes. This led to identification of issues impacting the most on access to learning and development by older workers and towards a revised TEM. Findings presented majority support for transitional employment as a strategy for supporting older workers to work beyond their traditional retirement age. Those findings are presented as significant issues impacting on access to transitional employment within the final 3-dimensionsal TEM. The model is intended as a guide for responding to an ageing workforce by local government councils in the future. This study argued for increased and improved corporate support, particularly for learning and development services for older workers. Such support will enable older workers to maintain their employability and extend their working lives; a sustainable workforce in the future.

Classifier selection using sequential error ratio criterion for multi-instance and multi-sample fusion

Classifier selection is a problem encountered by multi-biometric systems that aim to improve performance through fusion of decisions. A particular decision fusion architecture that combines multiple instances (n classifiers) and multiple samples (m attempts at each classifier) has been proposed in previous work to achieve controlled trade-off between false alarms and false rejects. Although analysis on text-dependent speaker verification has demonstrated better performance for fusion of decisions with favourable dependence compared to statistically independent decisions, the performance is not always optimal. Given a pool of instances, best performance with this architecture is obtained for certain combination of instances. Heuristic rules and diversity measures have been commonly used for classifier selection but it is shown that optimal performance is achieved for the `best combination performance' rule. As the search complexity for this rule increases exponentially with the addition of classifiers, a measure - the sequential error ratio (SER) - is proposed in this work that is specifically adapted to the characteristics of sequential fusion architecture. The proposed measure can be used to select a classifier that is most likely to produce a correct decision at each stage. Error rates for fusion of text-dependent HMM based speaker models using SER are compared with other classifier selection methodologies. SER is shown to achieve near optimal performance for sequential fusion of multiple instances with or without the use of multiple samples. The methodology applies to multiple speech utterances for telephone or internet based access control and to other systems such as multiple finger print and multiple handwriting sample based identity verification systems.

Making the train : an examination of five perspectives of rail access and how they resonate with existing and potential passengers

Rail operators recognize a need to increase ridership in order to improve the economic viability of rail service, and to magnify the role that rail travel plays in making cities feel liveable. This study extends previous research that used cluster analysis with a small sample of rail passengers to identify five salient perspectives of rail access (Zuniga et al, 2013). In this project stage, we used correlation techniques to determine how those perspectives would resonate with two larger study populations, including a relatively homogeneous sample of university students in Brisbane, Australia and a diverse sample of rail passengers in Melbourne, Australia. Findings from Zuniga et al. (2013) described a complex typology of current passengers that was based on respondents’ subjective attitudes and perceptions rather than socio-demographic or travel behaviour characteristics commonly used for segmentation analysis. The typology included five qualitative perspectives of rail travel. Based on the transport accessibility literature, we expected to find that perspectives from that study emphasizing physical access to rail stations would be shared by current and potential rail passengers who live further from rail stations. Other perspectives might be shared among respondents who live nearby, since the relevance of distance would be diminished. The population living nearby would thus represent an important target group for increasing ridership, since making rail travel accessible to them does not require expansion of costly infrastructure such as new lines or stations. By measuring the prevalence of each perspective in a larger respondent pool, results from this study provide insight into the typical socio-demographic and travel behaviour characteristics that correspond to each perspective of intra-urban rail travel. In several instances, our quantitative findings reinforced Zuniga et al.’s (2013) qualitative descriptions of passenger types, further validating the original research. This work may directly inform rail operators’ approach to increasing ridership through marketing and improvements to service quality and station experience. Operators in other parts of Australia and internationally may also choose to replicate the study locally, to fine-tune understanding of diverse customer bases. Developing regional and international collaboration would provide additional opportunities to evaluate and benchmark service and station amenities as they address the various access dimensions.

Experiments with cooperative control of underwater robots

In this paper we describe cooperative control algorithms for robots and sensor nodes in an underwater environment. Cooperative navigation is defined as the ability of a coupled system of autonomous robots to pool their resources to achieve long-distance navigation and a larger controllability space. Other types of useful cooperation in underwater environments include: exchange of information such as data download and retasking; cooperative localization and tracking; and physical connection (docking) for tasks such as deployment of underwater sensor networks, collection of nodes and rescue of damaged robots. We present experimental results obtained with an underwater system that consists of two very different robots and a number of sensor network modules. We present the hardware and software architecture of this underwater system. We then describe various interactions between the robots and sensor nodes and between the two robots, including cooperative navigation. Finally, we describe our experiments with this underwater system and present data.

The cultural impact of institutional remix : the formalisation of textual reappropriation within the ABC

In 2009, Mark Deuze proposed an updated approach to media studies to incorporate ‘media life’, a concept he suggests addresses the invisibleness of ubiquitous media. Media life provides a useful lens for researchers to understand the human condition in media and not with media. At a similar time, public service media (PSM) strategies have aligned audience participation with the so‐called Reithian trinity which suggest the PSB should inform, educate and entertain while performing its core values of public service broadcasting (Enli 2008). Remix within the PSM institution relies on audience participation, employing ‘the people formerly known as the audience’ (Rosen 2006) as cultural artifact producers, and draws on their experience from within the media. Remix as a practice then enables us to examine the shift of the core PSM values by understanding how audience participation, informed by a human condition mobilised from our existence of being in media and not merely with media. However, remix within PSM challenges the once elitist construction of meaning models with an egalitarian approach towards socially reappropriated texts, questioning its affect on the cultural landscape. This paper draws on three years of ethnographic data from within the Australian Broadcasting Corporation (ABC), exploring the remix culture of ABC Pool. ABC Pool operates under a Creative Commons licensing regime to enable remix practice under the auspices of the ABC. ABC Pool users provide a useful group of remix practitioners to examine as they had access to a vast ABC archival collection and were invited to remix those cultural artefacts, often adding cultural and fiscal value. This paper maintains a focus on the audience participation within PSM through remix culture by applying media dependency theory to remix as cultural practice and calls to expand and update the societal representation within the ABC.

Communication models of institutional online communities : the role of the ABC cultural intermediary

The co-creation of cultural artefacts has been democratised given the recent technological affordances of information and communication technologies. Web 2.0 technologies have enabled greater possibilities of citizen inclusion within the media conversations of their nations. For example, the Australian audience has more opportunities to collaboratively produce and tell their story to a broader audience via the public service media (PSM) facilitated platforms of the Australian Broadcasting Corporation (ABC). However, providing open collaborative production for the audience gives rise to the problem, how might the PSM manage the interests of all the stakeholders and align those interests with its legislated Charter? This paper considers this problem through the ABC’s user-created content participatory platform, ABC Pool and highlights the cultural intermediary as the role responsible for managing these tensions. This paper also suggests cultural intermediation is a useful framework for other media organisations engaging in co-creative activities with their audiences.

Communication models of institutional online communities : the role of the ABC cultural intermediary

The co-creation of cultural artefacts has been democratised given the recent technological affordances of information and communication technologies. Web 2.0 technologies have enabled greater possibilities of citizen inclusion within the media conversations of their nations. For example, the Australian audience has more opportunities to collaboratively produce and tell their story to a broader audience via the public service media (PSM) facilitated platforms of the Australian Broadcasting Corporation (ABC). However, providing open collaborative production for the audience gives rise to the problem, how might the PSM manage the interests of all the stakeholders and align those interests with its legislated Charter? This paper considers this problem through the ABC’s user-created content participatory platform, ABC Pool and highlights the cultural intermediary as the role responsible for managing these tensions. This paper also suggests cultural intermediation is a useful framework for other media organisations engaging in co-creative activities with their audiences.

The other APT : an exhibition of other perspectives

It’s hard not to be somewhat cynical about the self-congratulatory ‘diversity’ at the centre of the growing calendar of art bi/tri-ennials. The –ennial has proven expedient to the global tourism circuit, keeping regional economies and a relatively moderate pool of transnational artists afloat and the Asia Pacific Triennial is no exception. The mediation of representation that is imperative to the ‘best of’ formats of these transnational art shows hinges on a categorical backwardness that can feel more than a little like a Miss World competition than a progressive art show because the little tag in parenthesis after each artist’s name seems just as politically precarious now as it did forty years ago. Despite a weighty corpus of practical and critical work to the contrary, identity politics are so intrinsic to art capitalization, for both artists and institutions, that extricating ourselves from the particular and strategic politics of identification is seemingly impossible. Not that everyone wants to of course.

A phase II study of the modulation of 5-fluorouracil and folinic acid with high-dose infusional hydroxyurea in metastatic colorectal carcinoma

Background: Hydroxyurea (HU), an inhibitor of ribonucleotide reductase, may potentiate the activity of 5-fluorouracil (5-FU) and folinic acid (FA) by reducing the deoxyribonucleotide pool available for DNA synthesis and repair. However as HU may inhibit the formation of 5-fluoro-2-deoxyuridine-5- monophosphate (FdUMP), one of the principal active metabolites of 5-FU, the scheduling of HU may be critical. In vitro experiments suggest that administration of HU following 5-FU, maintaining the concentration in the region of I mM for six or more hours, significantly enhances the efficacy of 5-FU. Patients and methods: 5-FU/FA was given as follows: days 1 and 2 - FA 250 mg/m 2 (max. 350 mg) over two hours followed by 5-FU 400 mg/m 2 by intravenous bolus (ivb) over 15 minutes and subsequently 5-FU 400 mg/m 2 infusion (ivi) over 22 hours. HU was administered on day 3 immediately after the 5-FU with 3 g ivb over 15 minutes followed by 12 g ivi over 12 hours. Results: Thirty patients were entered into the study. Median survival was nine months (range 1-51 + months). There were eight partial responses (28%, 95% CI: 13%-47%). The median duration of response was 6.5 (range 4-9 months). Grade 3-4 toxicities included neutropenia (grade 3 in eight patients and grade 4 in five), anaemia (grade 3 in one patient) and diarrhoea (grade 3 in two patients). Neutropenia was associated with pyrexia in two patients. Phlebitis at the infusion site occurred in five patients. The treatment was complicated by pulmonary embolism in one patient and deep venous thrombosis in another. Conclusion: HU administered in this schedule is well tolerated. Based on these results and those of other phase II studies, a randomised phase III study of 5-FU, FA and HU versus 5-FU and FA using the standard de Gramont schedule is recommended.