Empirical Evaluation of the Parallel Distribution Sweeping Framework on Multicore Architectures

In this paper, we perform an empirical evaluation of the Parallel External Memory (PEM) model in the context of geometric problems. In particular, we implement the parallel distribution sweeping framework of Ajwani, Sitchinava and Zeh to solve batched 1-dimensional stabbing max problem. While modern processors consist of sophisticated memory systems (multiple levels of caches, set associativity, TLB, prefetching), we empirically show that algorithms designed in simple models, that focus on minimizing the I/O transfers between shared memory and single level cache, can lead to efficient software on current multicore architectures. Our implementation exhibits significantly fewer accesses to slow DRAM and, therefore, outperforms traditional approaches based on plane sweep and two-way divide and conquer.Comment: Longer version of ESA'13 pape

Characterizing the performance of Flash memory storage devices and its impact on algorithm design

Initially used in digital audio players, digital cameras, mobile phones, and USB memory sticks, flash memory may become the dominant form of end-user storage in mobile computing, either completely replacing the magnetic hard disks or being an additional secondary storage. We study the design of algorithms and data structures that can exploit the flash memory devices better. For this, we characterize the performance of NAND flash based storage devices, including many solid state disks. We show that these devices have better random read performance than hard disks, but much worse random write performance. We also analyze the effect of misalignments, aging and past I/O patterns etc. on the performance obtained on these devices. We show that despite the similarities between flash memory and RAM (fast random reads) and between flash disk and hard disk (both are block based devices), the algorithms designed in the RAM model or the external memory model do not realize the full potential of the flash memory devices. We later give some broad guidelines for designing algorithms which can exploit the comparative advantages of both a flash memory device and a hard disk, when used together

Relation of wheat yield with parameters derived from a spectral growth profile

An attempt has been made to generate crop growth profiles using multi-date NOAA AVHRR data of wheat-growing season of 1987-88 for the districts of Punjab and Haryana states of India. A profile model proposed by Badhwar was fitted to the multi-date Normalised Difference Vegetation Index (NDVI) values obtained from geographically referenced samples in each district. A novel approach of deriving a set of physiologically meaningful profile parameters has been outlined and the relation of these parameters with district wheat yields has been studied in order to examine the potential of growth profiles for crop-yield modelling. The parameter 'area under the profile' is found to be the best estimator of yield. However, with such a parameter time available for prediction gets reduced. Combination of different profile parameters shows improvement in correlation but lacks the consistency for individual state data

Age standardisation – an indigenous standard?

The study of inequities in health is a critical component of monitoring government obligations to uphold the rights of Indigenous Peoples. In Aotearoa/New Zealand the indigenous Māori population has a substantially younger age structure than the non-indigenous population making it necessary to account for age differences when comparing population health outcomes. An age-standardised rate is a summary measure of a rate that a population would have if it had a standard age structure. Changing age standards have stimulated interest in the potential impact of population standards on disparities data and consequently on health policy

Combining elements of the CO-OP Approach™ with education to promote healthy eating among older adults: A pilot study

This paper describes an exploratory study developing the Baycrest Brain-healthy Eating Approach (BBEA). Poor diet is a modifiable risk factor for many health problems including dementia. Mediterranean type diets, high in plant-based foods, rich in poly- and mono- unsaturated fatty acids with minimal consumption of saturated fat, red meat, and processed foods, are considered brain healthful. While several dementia prevention trials randomized controlled trials have included nutritional counselling in favor of these diets as one component of their interventions, the extent to which dietary change occurred is not known. Based on observations that a strategy training approach, the Cognitive Orientation to daily Occupational Performance (CO-OP) Approach, was beneficial for promoting lifestyle changes in older adults with complaints of cognitive changes, we undertook to develop the BBEA combining elements of CO-OP with didactic nutrition education. This exploratory, descriptive study assesses the feasibility and acceptability of the BBEA. Healthy community dwelling older adults (n = 5) were recruited using convenience sampling. Participants received five, 2 h, group sessions. During these sessions participants were supported in adopting dietary practices consistent with brain healthy eating. Each participant set specific dietary goals important to them. Feasibility of the intervention was demonstrated through high levels of attendance and by the findings that at each session, all participants set personally meaningful goals and received education on selected brain healthy eating topics. Acceptability was demonstrated through participants' positive reports of their experiences and perspectives obtained via semi-structured interviews. Thus, the BBEA appears to be feasible and acceptable

Open Problems in (Hyper)Graph Decomposition

Large networks are useful in a wide range of applications. Sometimes problem instances are composed of billions of entities. Decomposing and analyzing these structures helps us gain new insights about our surroundings. Even if the final application concerns a different problem (such as traversal, finding paths, trees, and flows), decomposing large graphs is often an important subproblem for complexity reduction or parallelization. This report is a summary of discussions that happened at Dagstuhl seminar 23331 on "Recent Trends in Graph Decomposition" and presents currently open problems and future directions in the area of (hyper)graph decomposition

The 'Women's Lifestyle Study', 2-year randomized controlled trial of physical activity counselling in primary health care: rationale and study design

<p>Abstract</p> <p>Background</p> <p>Physical inactivity is an independent risk factor for diabetes and heart disease. There is evidence that increasing physical activity can reduce the risk of developing these chronic diseases, but less evidence about effective ways to increase adherence to physical activity. Interventions are therefore needed that produce sustained increases in adherence to physical activity, are cost-effective and improve clinical endpoints.</p> <p>Methods</p> <p>The Women's Lifestyle Study is a two year randomized controlled trial involving a nurse-led intervention to increase physical activity in 40–74 year old physically inactive women recruited from primary care. Baseline measures were assessed in a face-to-face interview with a primary care nurse. The intervention involved delivery of a 'Lifestyle script' by a primary care nurse followed by telephone counselling for nine months and a face-to-face nurse visit at six months. Outcome measurements are assessed at 12 and 24 months. The primary outcome is physical activity measured using a validated physical activity questionnaire. Secondary outcomes include blood pressure, weight, waist circumference, physical fitness (step test), serum HbA1c, fasting glucose, lipids, insulin, and quality of life (SF36). Costs were measured prospectively to allow a subsequent cost-effectiveness evaluation if the trial is positive.</p> <p>Discussion</p> <p>Due to report in 2008, the Women's Lifestyle Study tests the effectiveness of an enhanced low-cost, evidence-based intervention in increasing physical activity, and improving cardiovascular and diabetes risk indicators over two years. If successful in demonstrating improvements in health outcomes, this randomized controlled trial will be the first to demonstrate long-term cardiovascular and diabetes risk health benefit, in addition to improvements in physical activity, from a sustainable physical activity intervention based in primary care.</p> <p>Trial Registration</p> <p>Australian Clinical Trials Registry (ACTR), ACTRN012605000490673.</p

Tackling health inequalities: moving theory to action

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Children admitted to hospital following unintentional injury: perspectives of health service providers in Aotearoa/New Zealand

<p>Abstract</p> <p>Background</p> <p>Unintentional injuries are the leading cause of death and hospitalisation among New Zealand children, with indigenous Māori and ethnic minority Pacific children significantly over represented in these statistics. International research has shown that many children hospitalised for injury, as well as their families experience high levels of stress, and ethnic disparities in the quality of trauma care are not uncommon. The research on which this paper is based sought to identify key issues and concerns for New Zealand's multi-ethnic community following hospitalisation for childhood injury in order to inform efforts to improve the quality of trauma services. This paper reports on service providers' perspectives complementing previously published research on the experiences of families of injured children.</p> <p>Methods</p> <p>A qualitative research design involving eleven in-depth individual interviews and three focus groups was used to elicit the views of 21 purposefully selected service provider key informants from a range of professional backgrounds involved in the care and support of injured children and their families in Auckland, New Zealand. Interviews were transcribed and data were analysed using thematic analysis.</p> <p>Results</p> <p>Key issues identified by service providers included limited ability to meet the needs of children with mild injuries, particularly their emotional needs; lack of psychological support for families; some issues related to Māori and Pacific family support services; lack of accessible and comprehensive information for children and families; poor staff continuity and coordination; and poor coordination of hospital and community services, including inadequacies in follow-up plans. There was considerable agreement between these issues and those identified by the participant families.</p> <p>Conclusions</p> <p>The identified issues and barriers indicate the need for interventions for service improvement at systemic, provider and patient levels. Of particular relevance are strategies that enable families to have better access to information, including culturally appropriate oral and written sources; improve communication amongst staff and between staff and families; and carefully developed discharge plans that provide care continuity across boundaries between hospital and community settings. Māori and Pacific family support services are important and need better resourcing and support from an organisational culture responsive to the needs of these populations.</p

Indigenous well-being in four countries: An application of the UNDP'S Human Development Index to Indigenous Peoples in Australia, Canada, New Zealand, and the United States

<p>Abstract</p> <p>Background</p> <p>Canada, the United States, Australia, and New Zealand consistently place near the top of the United Nations Development Programme's <it>Human Development Index (HDI) </it>rankings, yet all have minority Indigenous populations with much poorer health and social conditions than non-Indigenous peoples. It is unclear just how the socioeconomic and health status of Indigenous peoples in these countries has changed in recent decades, and it remains generally unknown whether the overall conditions of Indigenous peoples are improving and whether the gaps between Indigenous peoples and other citizens have indeed narrowed. There is unsettling evidence that they may not have. It was the purpose of this study to determine how these gaps have narrowed or widened during the decade 1990 to 2000.</p> <p>Methods</p> <p>Census data and life expectancy estimates from government sources were used to adapt the Human Development Index (HDI) to examine how the broad social, economic, and health status of Indigenous populations in these countries have changed since 1990. Three indices – life expectancy, educational attainment, and income – were combined into a single HDI measure.</p> <p>Results</p> <p>Between 1990 and 2000, the HDI scores of Indigenous peoples in North America and New Zealand improved at a faster rate than the general populations, closing the gap in human development. In Australia, the HDI scores of Indigenous peoples decreased while the general populations improved, widening the gap in human development. While these countries are considered to have high human development according to the UNDP, the Indigenous populations that reside within them have only medium levels of human development.</p> <p>Conclusion</p> <p>The inconsistent progress in the health and well-being of Indigenous populations over time, and relative to non-Indigenous populations, points to the need for further efforts to improve the social, economic, and physical health of Indigenous peoples.</p