Comparing the small sample properties of two break Lagrange Multiplier unit root tests

In this note, we examine the size and power properties and the break date estimation accuracy of the Lee and Strazicich (LS, 2003) two break endogenous unit root test, based on two different break date selection methods: minimising the test statistic and minimising the sum of squared residuals (SSR). Our results show that the performance of both Models A and C of the LS test are superior when one uses the minimising SSR procedure.

Rapid multi sample DNA amplification using rotary-linear polymerase chain reaction device (PCRDisc)

Multiple sample DNA amplification was done by using a novel rotary-linear motion polymerase chain reaction (PCR) device. A simple compact disc was used to create the stationary sample chambers which are individually temperature controlled. The PCR was performed by shuttling the samples to different temperature zones by using a combined rotary-linear movement of the disc. The device was successfully used to amplify up to 12 samples in less than 30 min with a sample volume of 5 μl. A simple spring loaded heater mechanism was introduced to enable good thermal contact between the samples and the heaters. Each of the heater temperatures are controlled by using a simple proportional–integral–derivative pulse width modulation control system. The results show a good improvement in the amplification rate and duration of the samples. The reagent volume used was reduced to nearly 25% of that used in conventional method.

Diabetes MILES – The Netherlands: rationale, design and sample characteristics of a national survey examining the psychosocial aspects of living with diabetes in Dutch adults

Background : As the number of people with diabetes is increasing rapidly worldwide, a more thorough understanding of the psychosocial aspects of living with this condition has become an important health care priority. While our knowledge has grown substantially over the past two decades with respect to the physical, emotional and social difficulties that people with diabetes may encounter, many important issues remain to be elucidated. Under the umbrella of the Diabetes MILES (Management and Impact for Long-term Empowerment and Success) Study International Collaborative, Diabetes MILES – The Netherlands aims to examine how Dutch adults with diabetes manage their condition and how it affects their lives. Topics of special interest in Diabetes MILES - The Netherlands include subtypes of depression, Type D personality, mindfulness, sleep and sexual functioning.

Methods/design : Diabetes MILES – The Netherlands was designed as a national online observational study among adults with diabetes. In addition to a main set of self-report measures, the survey consisted of five complementary modules to which participants were allocated randomly. From September to October 2011, a total of 3,960 individuals with diabetes (40% type 1, 53% type 2) completed the battery of questionnaires covering a broad range of topics, including general health, self-management, emotional well-being and contact with health care providers. People with self-reported type 1 diabetes (specifically those on insulin pump therapy) were over-represented, as were those using insulin among respondents with self-reported type 2 diabetes. People from ethnic minorities were under-represented. The sex distribution was fairly equal in the total sample, participants spanned a broad age range (19–90 years), and diabetes duration ranged from recent diagnosis to living with the condition for over fifty years.

Discussion : The Diabetes MILES Study enables detailed investigation of the psychosocial aspects of living with diabetes and an opportunity to put these findings in an international context. With several papers planned resulting from a pooled Australian-Dutch dataset and data collections planned in other countries, the Diabetes MILES Study International Collaborative will contribute substantially to identifying potentially unmet needs of those living with diabetes and to inform clinical research and care across the globe.

Mother-daughter communication about mammography in an Australian sample

Breast cancer is a significant health problem for aging women. Despite constant efforts to promote mammography in Australia to facilitate early detection, screening rates through the national mammography screening service remain at just 57%. Based on a theoretical rationale informed by Family Communication Patterns theory, the current study used semi-structured interviews with Australian mother-daughter dyads (N = 8) to examine their health communication, with a view to exploring the potential for daughters to deliver mammography promotion messages to their mothers. Consistent with results of previous studies conducted in different cultural contexts, the Australian mothers and daughters in this sample frequently communicated about health topics. Daughters were a source of information and influence for their mother's health decision making. The delivery of mammography promotion messages to the mother by the daughter may be most successful for dyads that value bidirectional conversation. Aspects of the Australian culture may facilitate the success of this strategy.

Validation of autism spectrum quotient ddult version in an Australian sample

The Autism Spectrum Quotient is used to assess autistic spectrum traits in intellectually competent adults in both the general population and the autism spectrum community. While the autism spectrum Quotient has been validated in several different cultures, to date no study has assessed the psychometrics of the Autism Spectrum Quotient on an Australian population. The purpose of this study was to assess the psychometrics of the autism spectrum Quotient in an Australian sample of both typically developing individuals (n = 128) and individuals with autism spectrum disorder (n = 104). The results revealed that the internal consistency and the test-retest reliability were satisfactory; individuals with autism spectrum disorder scored higher on total Autism Spectrum Quotient score and its subscales than typically developing individuals; however, gender differences were not apparent on total score. Possible cultural differences may explain some of the psychometric variations found. The results of this analysis revealed that the Autism Spectrum Quotient was a reliable instrument for investigating variation in autistic symptomology in both typically developing and Autism Spectrum Disorders populations within an Australian population.

Comparison of advanced waste heat recovery systems with a novel oil heating system

Latest trends in waste heat recovery include systems like Thermo Electric Generation (TEG), Rankine cycle, and active warm up systems. The advantages and disadvantages of different approaches are critically discussed and compared with a novel and effective oil heating system that can deliver between 7% and 12% reductions of CO2 emissions and fuel consumption. The comparison includes the expected CO2 and fuel saving potential related to the legal drive cycle as well as real world driving, effects on regulated exhaust emissions, utilisation of resources, maintenance and service, vehicle performance, comfort, noise, and durability.

Alcohol consumption and body composition in a population-based sample of elderly Australian men

Background: Alcohol is calorie dense, and impacts activity, appetite and lipid processing. The aim of this study was to therefore investigate the association between alcohol consumption and components of body composition including bone, fat and lean tissue.

Methods: Participants were recruited from a randomly selected, population-based sample of 534 men aged 65 years and older enrolled in the Geelong Osteoporosis Study. Alcohol intake was ascertained using a food frequency questionnaire and the sample categorised as nondrinkers or alcohol users who consumed B2, 3–4 or C5 standard drinks on a usual drinking day. Bone mineral density (BMD), lean body mass and body fat mass were measured using dual energy X-ray absorptiometry; overall adiposity (%body fat), central adiposity (%truncal fat) and body mass index (BMI) were calculated. Bone quality was determined by quantitative heel ultrasound (QUS).

Results: There were 90 current non-drinkers (16.9 %), 266 (49.8 %) consumed 1–2 drinks/day, 104 (19.5 %) 3–4 drinks/day and 74 (13.8 %) C5 drinks/day. Those consuming C5 drinks/day had greater BMI (?4.8 %), fat mass index (?20.1 %), waist circumference (?5.0 %), %body fat (?15.2 %) and proportion of trunk fat (?5.3 %) and lower lean mass (-5.0 %) than non-drinkers after adjustment for demographic and lifestyle factors. Furthermore, they were more likely to be obese than non-drinkers according to criteria based on BMI (OR = 2.83, 95 %CI 1.10–7.29) or waist circumference (OR = 3.36, 95 %CI 1.32–8.54). There was an inverse relationship between alcohol consumption and QUS parameters and BMD at the mid forearm site; no differences were detected for BMD at other skeletal sites.

Conclusion: Higher alcohol intake was associated with greater total and central adiposity and reduced bone quality.

Shape evolution of silver nanoplates through heating and photoinduction

Shape conversions of silver nanoplates were realized by heating and subsequent light irradiation. The initial silver nanoprisms were transformed into silver nanodisks gradually in the process of heating, which was possibly achieved through dissolving and readsorption of silver atoms on the surface of silver nanoplates. Subsequently, under light irradiation, the heating induced silver nanodisks were reversed to silver nanoprisms in the same solution. The dissolved oxygen was found to play a pivotal role in the shape conversion from nanoprism to nanodisk. In addition to heating, deionized water could induce the shape conversion of silver nanoplates when it was added to precipitate of the initial silver nanoprisms after centrifugation. Citrate in solution is essential to the photoinduced shape conversion process. Transmission electron microscopy (TEM) and extinction spectroscopy results demonstrated that localized surface plasmon resonance (LSPR) properties of silver nanoplates were effectively tuned through shape conversion.

Reliability and validity of the IPAQ-L in a sample of Hong Kong urban older adults : does neighborhood of residence matter?

This study examined reliability and validity of the Chinese version of the International Physical Activity Questionnaire–Long Form (IPAQ-LC) in Chinese seniors, including moderating effects of neighborhood walkability and socioeconomic status (SES) on reliability and validity. The IPAQ-LC was interviewer-administered (n = 96), accelerometer and 7-day walk-diary data were collected (n = 94), and the IPAC-LC was readministered (N = 92). Acceptable reliability was found for all measures of physical activity (PA) overall and across different types of neighborhood. Participants from highly walkable neighborhoods were more reliable at estimating walking for transport. Participants from low-SES areas were less reliable at estimating leisure-time PA and sitting but more reliable at estimating transport-related walking. IPAQ-LC walking was significantly related to light- but not moderate-intensity accelerometry-based PA. It was moderately to strongly related to a 7-day diary of walking. The data imply slow-paced walking, probably due to age, climate, and terrain. The findings suggest that the IPAQ-LC’s reliability and validity are acceptable in Chinese seniors.

Physical activity, activity change, and their correlates in a population-based sample of colorectal cancer survivors

Background: Physical activity can provide benefits to cancer survivors, including reduced symptoms and treatment side effects, improved overall quality of life, and decreased risk of other chronic diseases.

Purpose: The aim of the study was to describe physical activity before and after diagnosis of colorectal cancer and to examine the associations with sociodemographic and disease-related variables.

Methods: Telephone interviews were conducted with 1,996 colorectal cancer survivors recruited through a cancer registry.

Results: In comparison to prediagnosis activity levels, there were 21% fewer participants meeting the physical activity and health guideline (150 min of moderate-intensity physical activity per week) postdiagnosis. Meeting the guideline postdiagnosis was associated with being male, living outside of the state capital city, having a higher education, having a healthy body mass index, not smoking, having had surgery only, and no reported fatigue. Attributes associated with a decrease in physical activity following diagnosis were being female, living within the state capital city, having a lower level of education, having a stoma, having adjuvant therapy, and experiencing fatigue.

Conclusions: There is considerable scope for targeted interventions to increase the physical activity of colorectal cancer survivors, particularly for those groups that we have identified as being less active and/or have reduced their activity.

Associations of leisure-time physical activity with quality of life in a large, population-based sample of colorectal cancer survivors

Objective : To examine the associations between physical activity and quality of life for colorectal cancer survivors; and to describe the associations of medical and sociodemographic attributes with overall quality of life, and their moderating effects on the relationships between physical activity and quality of life.

Methods : Telephone interviews were conducted with 1,996 colorectal cancer survivors recruited through the Queensland Cancer Registry. Data were collected on current quality of life; leisure-time physical activity pre- and post-diagnosis; cancer treatment and side-effects; and general sociodemographic attributes. Hierarchical generalized linear models identified variables significantly associated with quality of life.

Results : After controlling for sociodemographic variables, disease-specific variables, treatment side-effects, and pre-diagnosis leisure-time physical activity, there were significant differences in quality of life scores by post-diagnosis physical activity category. Compared to participants who were inactive after their diagnosis, those who were sufficiently active had a 17.0% higher total quality of life score. Physical activity also had a significant independent positive association with the physical well-being, functional well-being, and additional concerns subscales of the FACT-C.

Conclusions : Our findings demonstrate that quite modest changes in leisure-time physical activity are associated with quality of life. Colorectal cancer survivors may benefit from a more active lifestyle.