Improving the PLDA based speaker verification in limited microphone data conditions

A significant amount of speech data is required to develop a robust speaker verification system, but it is difficult to find enough development speech to match all expected conditions. In this paper we introduce a new approach to Gaussian probabilistic linear discriminant analysis (GPLDA) to estimate reliable model parameters as a linearly weighted model taking more input from the large volume of available telephone data and smaller proportional input from limited microphone data. In comparison to a traditional pooled training approach, where the GPLDA model is trained over both telephone and microphone speech, this linear-weighted GPLDA approach is shown to provide better EER and DCF performance in microphone and mixed conditions in both the NIST 2008 and NIST 2010 evaluation corpora. Based upon these results, we believe that linear-weighted GPLDA will provide a better approach than pooled GPLDA, allowing for the further improvement of GPLDA speaker verification in conditions with limited development data.

Work motivation as a determinant of organisational and professional commitment in temporary organisations : theoretical lenses and propositions

The purpose of this paper is to present a theoretical framework to investigate the relationship between work motivation, organisational commitment and professional commitment in temporary organisations. Through a review of theory, we contend that work motivation has two major patterns — internal motivation (which includes intrinsic, need-based and self-deterministic theories), and external motivation (which includes cognitive or process-based theories of motivation) through which it has been investigated. We also hold the nature of employee commitment to be of three types — affective, continuance and normative. This commitment may be towards either the organisation or the profession. A literature review revealed that the characteristics of the temporary organisation — specifically tenure and task — regulate the relationship between work motivation, organisational commitment and professional commitment. Testable propositions are presented.

End-of-life care in the critical care setting : nurses' practices and factors affecting these practices

Background: Critical care units are designed and resourced to save lives, yet the provision of end-of-life care is a significant component of nursing work in these settings. Limited research has investigated the actual practices of critical care nurses in the provision of end-of-life care, or the factors influencing these practices. To improve the care that patients at the end of life and their families receive, and to support nurses in the provision of this care, further research is needed. The purpose of this study was to identify critical care nurses' end-of-life care practices, the factors influencing the provision of end-of-life care and the factors associated with specific end-of-life care practices. Methods: A three-phase exploratory sequential mixed-methods design was utilised. Phase one used a qualitative approach involving interviews with a convenience sample of five intensive care nurses to identify their end-of-life care experiences and practices. In phase two, an online survey instrument was developed, based on a review of the literature and the findings of phase one. The survey instrument was reviewed by six content experts and pilot tested with a convenience sample of 28 critical care nurses (response rate 45%) enrolled in a postgraduate critical care nursing subject. The refined survey instrument was used in phase three of this study to conduct a national survey of critical care nurses. Descriptive analyses, exploratory factor analysis and univariate general linear modelling was undertaken on completed survey responses from 392 critical care nurses (response rate 25%). Results: Six end-of-life care practice areas were identified in this study: information sharing, environmental modification, emotional support, patient and family-centred decision making, symptom management and spiritual support. The items most frequently identified as always undertaken by critical care nurses in the provision of end-of-life care were from the information sharing and environmental modification practice areas. Items least frequently identified as always undertaken included items from the emotional support practice area. Eight factors influencing the provision of end-of-life care were identified: palliative values, patient and family preferences, knowledge, preparedness, organisational culture, resources, care planning, and emotional support for nurses. Strong agreement was noted with items reflecting values consistent with a palliative approach and inclusion of patient and family preferences. Variation was noted in agreement for items regarding opportunities for knowledge acquisition in the workplace and formal education, yet most respondents agreed that they felt adequately prepared. A context of nurse-led practice was identified, with variation in access to resources noted. Collegial support networks were identified as a source of emotional support for critical care nurses. Critical care nurses reporting values consistent with a palliative approach and/or those who scored higher on support for patient and family preferences were more likely to be engaged in end-of-life care practice areas identified in this study. Nurses who reported higher levels of preparedness and access to opportunities for knowledge acquisition were more likely to report engaging in interpersonal practices that supported patient and family centred decision making and emotional support of patients and their families. A negative relationship was identified between the explanatory variables of emotional support for nurses and death anxiety, and the patient and family centred decision making practice area. Contextual factors had a limited influence as explanatory variables of specific end-of-life care practice areas. Gender was identified as a significant explanatory variable in the emotional and spiritual support practice areas, with male gender associated with lower summated scores on these practice scales. Conclusions: Critical care nurses engage in practices to share control with and support inclusion of families experiencing death and dying. The most frequently identified end-of-life care practices were those that are easily implemented, practical strategies aimed at supporting the patient at the end of life and the patient's family. These practices arguably require less emotional engagement by the nurse. Critical care nurses' responses reflected values consistent with a palliative approach and a strong commitment to the inclusion of families in end-of-life care, and these factors were associated with engagement in all end-of-life care practice areas. Perceived preparedness or confidence with the provision of end-of-life care was associated with engagement in interpersonal caring practices. Critical care nurses autonomously engage in the provision of end-of-life care within the constraints of an environment designed for curative care and rely on their colleagues for emotional support. Critical care nurses must be adequately prepared and supported to provide comprehensive care in all areas of end-of-life care practice. The findings of this study raise important implications, and informed recommendations for practice, education and further research.

Well-being, satisfaction and commitment : the substitutable nature of resources for maternity hospital nurses

Abstract Aims. To investigate the relationship between three types of organizational resources (job control, social support and organizational justice) and the impact of job demands on nurse’s well-being and attitudes towards their work. Background. The negative impact of work-related stress on nurse’s health and attitudes towards their work has been established. Increasingly, research is focusing on the role of organizational resources in reducing the impact of work related stress. Design. Cross-sectional survey. Method. Data collected in November 2008 from 226 Australian nurses and midwives were analysed using the full Job Strain Model with the addition of organizational justice variables. Multiple regression analyses explored the relationships among job control, job demands, three sources of social support and four types of organizational justice on well-being and work attitudes. Results. The overall regression models explained a significant amount of variance in well-being, job satisfaction and organizational commitment. Significant main effects were evident for support variables and organizational justice variables on well-being and job satisfaction. Interactions between job control and supervisor support and between job demands and supervisor support were evident for job satisfaction. Conclusions. Supervisor support and organizational justice have significant relationships with nurses’ well-being and job satisfaction. More broadly, the findings suggest that, in the triple-matching approach from a work-stressor to a resource to a work outcome, personal, supervisory and organizational resources may be substitutable. These findings provide nurse management with empirical endorsement for the development and delivery of the organization’s resources for nursing staff.

Improving PLDA speaker verification with limited development data

This paper analyses the probabilistic linear discriminant analysis (PLDA) speaker verification approach with limited development data. This paper investigates the use of the median as the central tendency of a speaker’s i-vector representation, and the effectiveness of weighted discriminative techniques on the performance of state-of-the-art length-normalised Gaussian PLDA (GPLDA) speaker verification systems. The analysis within shows that the median (using a median fisher discriminator (MFD)) provides a better representation of a speaker when the number of representative i-vectors available during development is reduced, and that further, usage of the pair-wise weighting approach in weighted LDA and weighted MFD provides further improvement in limited development conditions. Best performance is obtained using a weighted MFD approach, which shows over 10% improvement in EER over the baseline GPLDA system on mismatched and interview-interview conditions.

Contemporary comments: The limited benefit of prison in controlling crime

A number of recent developments in the United State (US), United Kingdom (UK) and Australia suggest that conditions may be ripe for a political shift in the reliance on escalating rates of imprisonment as a default criminal justice strategy for responding to crime. The default position is illustrated by the Yabsleyite response of former New South Wales (NSW) Premier Nathan Rees’s to questioning over the cost of prison building and NSW’s high recidivism rate: ‘[t]he advice to me is we have still got 500 cells empty, I don't mind if we fill them up, and if we fill them up and have to build another jail, we'll build another jail’ (Knox and Tadros 2008)...

Limited dengue virus replication in field-collected Aedes aegypti mosquitoes infected with Wolbachia

Introduction Dengue is one of the most widespread mosquito-borne diseases in the world. The causative agent, dengue virus (DENV), is primarily transmitted by the mosquito Aedes aegypti, a species that has proved difficult to control using conventional methods. The discovery that A. aegypti transinfected with the wMel strain of Wolbachia showed limited DENV replication led to trial field releases of these mosquitoes in Cairns, Australia as a biocontrol strategy for the virus. Methodology/Principal Findings Field collected wMel mosquitoes that were challenged with three DENV serotypes displayed limited rates of body infection, viral replication and dissemination to the head compared to uninfected controls. Rates of dengue infection, replication and dissemination in field wMel mosquitoes were similar to those observed in the original transinfected wMel line that had been maintained in the laboratory. We found that wMel was distributed in similar body tissues in field mosquitoes as in laboratory ones, but, at seven days following blood-feeding, wMel densities increased to a greater extent in field mosquitoes. Conclusions/Significance Our results indicate that virus-blocking is likely to persist in Wolbachia-infected mosquitoes after their release and establishment in wild populations, suggesting that Wolbachia biocontrol may be a successful strategy for reducing dengue transmission in the field.

The Limited Benefit of Prison in Controlling Crime : On the Threshold of a Political Shift

In 2012 the New Zealand government spent $3.4 billion, or nearly $800 per person, on responses to crime via the justice system. Research shows that much of this spending does little to reduce the changes of re-offending. Relatively little money is spent on victims, the rehabilitation of offenders or to support the families of offenders. This book is based on papers presented at the Costs of Crime forum held by the Institute of Policy Studies in February 2011. It presents lessons from what is happening in Australia, Britain and the United States and focuses on how best to manage crime, respond to victims, and reduce offending in a cost-effective manner in a New Zealand context. It is clear that strategies are needed that are based on better research and a more informed approach to policy development. Such strategies must assist victims constructively while also reducing offending. Using public resources to lock as many people in our prisons as possible cannot be justified by the evidence and is fiscally unsustainable; nor does such an approach make society safer. To reduce the costs of crime we need to reinvest resources in effective strategies to build positive futures for those at risk and the communities needed to sustain them.

Accounting for forests in Fiji : the experience of Future Forests (Fiji) Limited

"in a world which is experiencing unprecedented deforestation and widespread global environmental threats there is something intuitively right about planting a tree" (Future Forests (Fiji) Limited) The above quote demonstrates that even in the wake of global environmental crisis that hope still remains and that humans can still control their destiny. This opportunity to effect positive environmental change is one of the main aims of the South Pacific Stock Exchange’s (SPSE) most recent publicly listed company: Future Forest (Fiji) Limited. Incorporated in 2004 and listed on SPSE in 2011, the company is Fiji’s first large-scale commercial hardwood forest plantation and nursery. Future Forest (FF) is the only company listed on the SPSE with biological assets or “living assets.” The accounting standard for biological assets is IAS 41: Agriculture. This standard prescribes the use of fair value as the basis of valuation. While a more relevant method of valuation, the application of fair value accounting can be more costly and burdensome for companies in developing economies (White 2008). In line with the journal’s theme of agriculture, this article explores the issues, challenges and potential benefits involved in applying fair value accounting for biological assets in a developing economy such as Fiji using the case of Future Forest (Fiji) Limited.

The heparan sulfate proteoglycan (HSPG) glypican-3 mediates commitment of MC3T3-E1 cells toward osteogenesis

Heparan sulfate (HS) sugar chains attached to core proteoglycans (PGs) termed HSPGs mediate an extensive range of cell-extracellular matrix (ECM) and growth factor interactions based upon their sulfation patterns. When compared with non-osteogenic (maintenance media) culture conditions, under established osteogenic culture conditions, MC3T3-E1 cells characteristically increase their osteogenic gene expression profile and switch their dominant fibroblast growth factor receptor (FGFR) from FGFR1 (0.5-fold decrease) to FGFR3 (1.5-fold increase). The change in FGFR expression profile of the osteogenic-committed cultures was reflected by their inability to sustain an FGF-2 stimulus, but respond to BMP-2 at day 14 of culture. The osteogenic cultures decreased their chondroitin and dermatan sulfate PGs (biglycan, decorin, and versican), but increased levels of the HS core protein gene expression, in particular glypican-3. Commitment and progress through osteogenesis is accompanied by changes in FGFR expression, decreased GAG initiation but increased N- and O-sulfation and reduced remodeling of the ECM (decreased heparanase expression) resulting in the production of homogenous (21 kDa) HS chain. With the HSPG glypican-3 expression strongly upregulated in these processes, siRNA was used to knockdown this gene to examine the effect on osteogenic commitment. Reduced glypican-3 abrogated the expression of Runx2, and thus differentiation. The reintroduction of this HSPG into Runx2-null cells allowed osteogenesis to proceed. These results demonstrate the dependence of osteogenesis on specific HS chains, in particular those associated with glypican-3.

Safety climate and injury occurrence of repair, maintenance, minor alteration and addition works : a comparison of workers, supervisors and managers

Purpose The repair, maintenance, minor alteration and addition (RMAA) sector has been expanding in many developed cities. Safety problems of the RMAA sector have attracted the attention of many governments. This study has the objectives of comparing the level of safety climate of workers, supervisors and managers in the RMAA sector; and explaining/ predicting the impact of safety climate on injury occurrence of workers, supervisors and managers. Design/methodology/approach A questionnaire survey was administered to RMAA contracting companies in Hong Kong. Findings When comparing the safety climate perception of workers, supervisors and managers in the RMAA sector, the supervisors group had the lowest mean safety climate score. Results showed that a positive workforce safety attitude and acceptance of safety rules and regulations reduced the workers’ likelihood of having injuries. A reasonable production schedule led to a lower probability of supervisors being injured. Management commitment and effective safety management reduced the probability of managers being injured. Originality/value This study revealed variations of safety climate at the different levels in the organizational hierarchy and their varying influence on safety performance of the RMAA sector. Safety of RMAA works could be improved by promulgating specific safety measures at the different hierarchy levels.

Determining safety climate factors in the repair, maintenance, minor alteration, and addition sector of Hong Kong

The accident record of the repair, maintenance, minor alteration, and addition (RMAA) sector has been alarmingly high; however, research in the RMAA sector remains limited. Unsafe behavior is considered one of the key causes of accidents. Thus, the organizational factors that influence individual safety behavior at work continue to be the focus of many studies. The safety climate, which reflects the true priority of safety in an organization, has drawn much attention. Safety climate measurement helps to identify areas for safety improvement. The current study aims to identify safety climate factors in the RMAA sector. A questionnaire survey was conducted in the RMAA sector in Hong Kong. Data were randomly split into the calibration and the validation samples. The RMAA safety climate factors were determined by exploratory factor analysis on the calibration sample. Three safety climate factors of the RMAA works were identified: (1) management commitment to occupational health and safety (OHS) and employee involvement, (2) application of safety rules and work practices, and; (3) responsibility for health and safety. Confirmatory factor analysis (CFA) was then conducted on the validation sample. The CFA model showed satisfactory goodness of fit, reliability, and validity. The suggested RMAA safety climate factors can be utilized by construction industry practitioners in developed economies to measure the safety climate of their RMAA projects, thereby enhancing the safety of RMAA works.

The global public health issue of pharmaceutical waste : what role for pharmacists?

Purpose Pharmaceuticals have played an important role in improving the quality of life of the human population in modern times. However, it must also be acknowledged that both the production and use of pharmaceuticals have a significant, negative impact on the environment and consequently, a negative impact on the health of humans and wildlife. This negative impact is due to the embedded carbon in pharmaceuticals' manufacture and distribution and the waste generated in their manufacture, consumption and disposal. Pharmaceutical waste is comprised of contaminated waste (unwanted pharmaceuticals and their original containers) and non-contaminated waste (non-hazardous packaging waste). The paper aims to discuss these issues. Design/methodology/approach The article is a literature review. Findings The article identified a gap in the literature around pharmacist attitudes and behaviour toward the environmentally responsible handling of pharmaceutical waste. Originality/value Pharmacists, with their professional commitment to the quality use of medicines and their active participation in the medicines management pathway, already play an important role in the more sustainable use of pharmaceuticals. Even so, they have the potential to play an even greater role with the environmentally responsible disposal of pharmaceutical waste (including packaging waste) and the education of other health professionals and the general public on this topic.

Rho GTPases mediate the mechanosensitive lineage commitment of neural stem cells

Adult neural stem cells (NSCs) play important roles in learning and memory and are negatively impacted by neurological disease. It is known that biochemical and genetic factors regulate self-renewal and differentiation, and it has recently been suggested that mechanical and solid-state cues, such as extracellular matrix (ECM) stiffness, can also regulate the functions of NSCs and other stem cell types. However, relatively little is known of the molecular mechanisms through which stem cells transduce mechanical inputs into fate decisions, the extent to which mechanical inputs instruct fate decisions versus select for or against lineage-committed blast populations, or the in vivo relevance of mechanotransductive signaling molecules in native stem cell niches. Here we demonstrate that ECM-derived mechanical signals act through Rho GTPases to activate the cellular contractility machinery in a key early window during differentiation to regulate NSC lineage commitment. Furthermore, culturing NSCs on increasingly stiff ECMs enhances RhoA and Cdc42 activation, increases NSC stiffness, and suppresses neurogenesis. Likewise, inhibiting RhoA and Cdc42 or downstream regulators of cellular contractility rescues NSCs from stiff matrix- and Rho GTPase-induced neurosuppression. Importantly, Rho GTPase expression and ECM stiffness do not alter proliferation or apoptosis rates indicating that an instructive rather than selective mechanism modulates lineage distributions. Finally, in the adult brain, RhoA activation in hippocampal progenitors suppresses neurogenesis, analogous to its effect in vitro. These results establish Rho GTPase-based mechanotransduction and cellular stiffness as biophysical regulators of NSC fate in vitro and RhoA as an important regulatory protein in the hippocampal stem cell niche.

Prediction with limited advice and multiarmed bandits with paid observations

We study two problems of online learning under restricted information access. In the first problem, prediction with limited advice, we consider a game of prediction with expert advice, where on each round of the game we query the advice of a subset of M out of N experts. We present an algorithm that achieves O(√(N/M)TlnN ) regret on T rounds of this game. The second problem, the multiarmed bandit with paid observations, is a variant of the adversarial N-armed bandit game, where on round t of the game we can observe the reward of any number of arms, but each observation has a cost c. We present an algorithm that achieves O((cNlnN) 1/3 T2/3+√TlnN ) regret on T rounds of this game in the worst case. Furthermore, we present a number of refinements that treat arm- and time-dependent observation costs and achieve lower regret under benign conditions. We present lower bounds that show that, apart from the logarithmic factors, the worst-case regret bounds cannot be improved.