Supramolecular selection in molecular alloys

Complexes of the type \[M(phen)3](PF6)2 (M = Ni(II), Fe(II), Ru(II) and phen = 1,10-phenanthroline) were found to co-crystallize to form molecular alloys (solid solutions of molecules) with general formula \[MAxMB1–x(phen)3](PF6)2·0.5H2O in which the relative concentrations of the metal complexes in the crystals closely match those in the crystallizing solution. Consequently, the composition of the co-crystals can be accurately predicted and controlled by modulating the relative concentrations of the metal complexes in the crystallizing solution. Although they are chemically and structurally similar, complexes of the type \[M(bipy)3](PF6)2 (M = Ni(II), Fe(II), Ru(II) and bipy = 2,2′-bipyridine) display markedly different behavior upon co-crystallization. In this case, the resulting co-crystals of general formula \[MAxMB1–x(bipy)3](PF6)2 have relative concentrations of the constituent complexes that are markedly different from the relative concentrations of the complexes initially present in the crystallizing solution. For example, when the nickel and iron complexes are co-crystallized from a solution containing a 50:50 ratio of each, the result is the formation of some crystals with a higher proportion of iron and others with a higher proportion of nickel. The relative concentrations of the metal complexes in the crystals can vary from those in the crystallizing solutions by as much as 15%. This result was observed for a range of combinations of metal complexes (Ni/Fe, Ni/Ru, and Fe/Ru) and a range of starting concentrations in the crystallizing solutions (90:10 through to 10:90 in 10% increments). To explain this remarkable result, we introduce the concept of “supramolecular selection”, which is a process driven by molecular recognition that leads to the partially selective aggregation of like molecules during crystallization.

Experiences with implementing common mathematical operations using field programmable gate arrays

Many computationally intensive scientific applications involve repetitive floating point operations other than addition and multiplication which may present a significant performance bottleneck due to the relatively large latency or low throughput involved in executing such arithmetic primitives on commod- ity processors. A promising alternative is to execute such primitives on Field Programmable Gate Array (FPGA) hardware acting as an application-specific custom co-processor in a high performance reconfig- urable computing platform. The use of FPGAs can provide advantages such as fine-grain parallelism but issues relating to code development in a hardware description language and efficient data transfer to and from the FPGA chip can present significant application development challenges. In this paper, we discuss our practical experiences in developing a selection of floating point hardware designs to be implemented using FPGAs. Our designs include some basic mathemati cal library functions which can be implemented for user defined precisions suitable for novel applications requiring non-standard floating point represen- tation. We discuss the details of our designs along with results from performance and accuracy analysis tests.

Ability of modal analysis to detect osseointegration of implants in transfemoral amputees : a physical model study

Owing to the successful use of non-invasive vibration analysis to monitor the progression of dental implant healing and stabilization, it is now being considered as a method to monitor femoral implants in transfemoral amputees. This study uses composite femur-implant physical models to investigate the ability of modal analysis to detect changes at the interface between the implant and bone simulating those that occur during osseointegration. Using electromagnetic shaker excitation, differences were detected in the resonant frequencies and mode shapes of the model when the implant fit in the bone was altered to simulate the two interface cases considered: firm and loose fixation. The study showed that it is beneficial to examine higher resonant frequencies and their mode shapes (rather than the fundamental frequency only) when assessing fixation. The influence of the model boundary conditions on the modal parameters was also demonstrated. Further work is required to more accurately model the mechanical changes occurring at the bone-implant interface in vivo, as well as further refinement of the model boundary conditions to appropriately represent the in vivo conditions. Nevertheless, the ability to detect changes in the model dynamic properties demonstrates the potential of modal analysis in this application and warrants further investigation.

Evaluation of screening tests for predicting older driver performance and safety assessed by an on-road test

A number of tests and test batteries are available for the prediction of older driver safety, but many of these have not been validated against standardized driving outcome measures. The aim of this study was to evaluate a series of previously described screening tests in terms of their ability to predict the potential for safe and unsafe driving. Participants included 79 community-dwelling older drivers (M=72.16 years, SD=5.46; range 65-88 years; 57 males and 22 females) who completed a previously validated multi-disciplinary driving assessment, a hazard perception test, a hazard change detection test and a battery of vision and cognitive tests. Participants also completed a standardized on-road driving assessment. The multi-disciplinary test battery had the highest predictive ability with a sensitivity of 80% and a specificity of 73%, followed by the hazard perception test which demonstrated a sensitivity of 75% and a specificity of 61%. These findings suggest that a relatively simple and practical battery of tests from a range of domains has the capacity to predict safe and unsafe driving in older adults.

Health Assessment and Physical Examination

"This first Australia and New Zealand edition of the comprehensive Estes’ Health Assessment and Physical Examination is designed to teach students to assess a patient’s physical, psychological, cultural and emotional dimensions of health as a foundation of nursing care. The skills of interviewing, inspection, percussion, palpation, auscultation, and documentation are defined to help students to make clinical assessments and promote healthy patient outcomes. A strong emphasis on science encompasses all the technical aspects of anatomy, physiology and assessment, while highlighting clinically relevant information. Emphasis on caring is displayed through themes of assessment of the whole person, which also encourages nurses to think about care for themselves as well as patients."--publisher website

Diet, physical activity and substrate oxidation : implications for appetite control, weight loss and body composition

In many countries, governments and health agencies are strongly promoting physical activity as a means to prevent the accumulation of fatness that leads to weight gain and obesity. However, there is often a resistance to respond to health promotion initiatives. For example, in the UK, the Chief Medical Officer has recently reported that 71% of women and 61% of men fail to carry out even the minimal amount of physical activity recommended in the government’s guidelines. Similarly, the Food safety Agency has promoted reductions in the intake of fat, sugar and salt but with very little impact on the pattern of consumption. Why is it that recommendations to improve health are so difficult to implement, and produce the desired outcome?

Increasing physical activity among women with young children: Results from the Proactive Mums Project

Context Evidence from the Australian Longitudinal Study of Women's Health suggests that mothers of young children have lower levels of physical activity (PA) than women of similar age without children. Objectives The aim of the ProActive Mums project was to determine the relative efficacy of two strategies designed to increase the proportion of mothers of young children who are meeting current PA guidelines, utilising child care centres (CCCs) as the setting for recruitment. Study Design The project used a randomised (after stratification to ensure even representation of CCCs from differing socio-economic areas) design incorporating repeated data collection from women in three groups, each consisting of 7 childcare centres (CCCs). Baseline surveys were completed by 554 mothers, with follow-up data collection immediately post-Intervention (8 weeks after baseline) and again 5 months later. Women from CCCs in Group 1 (control) received only the surveys throughout the duration of the project. Women from CCCs in Group 2 (information only) were given a print intervention, and women from CCCs in Group 3 were (in addition to being given the same print intervention as women from CCCs in Group 2) invited to to contribute to the development of, and participate in, strategies for the promotion of PA among mothers of young children. The two intervention strategies were extensively evaluated through a series of surveys and interviews. The Intervention The print intervention prescribed for women from CCCs in Group 2 and Group 3 consisted of an 8-page booklet containing motivational messages and information about physical activity. Women from CCCs in Group 3 were also invited to attend meetings at their CCC to identify strategies for increasing their PA. Contacts were made with key stakeholders in the community, including managers of sporting and recreation facilities, childcare service providers, and local councils. A wide range of strategies was developed during the intervention phase of the project, which specifically focused on the need to increase partner support and self-efficacy (or the confidence to be physically active). Results The mean age of participants was 33 (+ 4.8) years, and the mean number of children per family unit was 2.2 (± 0.9). At baseline, fewer than half the women were meeting current guidelines for adequate PA for health benefit, and there were no significant differences between groups in the proportion of women who were adequately active for health benefit. Women in Group 3 were significantly more likely to meet the guidelines at post-intervention follow-up than controls [OR = 1.71 (1.05-2.77)] after controlling for age and PA at baseline. There was no significant effect of the print intervention alone on meeting guidelines at post-intervention follow-up compared with controls, after controlling for age and PA at baseline [OR = 1.15 (0.70-1.89)]. Changes in Partner Support (PS) and Self Efficacy (SE) significantly predicted meeting current PA guidelines at post-intervention follow-up after controlling for baseline PA [∆ PS: OR = 2.29 (1.46-3.58); ∆ SE: OR = 1.86 (1.17- 2.94)]. The intervention effect in Group 3 was not maintained at long-term follow-up. Conclusions The findings indicate that a community participation approach that facilitates increased partner support and self-efficacy can be effective in increasing PA among mothers of young children. Changes in physical activity were found to be mediated by changes in partner support and self-efficacy for physical activity, suggesting that the intervention successfully targeted the individual characteristics it intended to, and that these variables do play an important role in increasing physical activity among women with young children. It is clear that further work needs to be done to explore methods of translating the short-term intervention effect shown in this study into long-term changes in PA behaviour. This study also provided insight into measurement issues in PA research and raised questions about self-report measures of PA and perceived constraints to being physically active. The results from post-study qualitative interviews suggest that many women at this life-stage experience time constraints which, when accompanied by a lack of partner support and financial constraints, make leisure-time PA virtually impossible for many women. Future strategies might focus on targeting this population immediately prior to this life-stage in an attempt to encourage habitual physical activity before women have children. Increasing PA in this population should also address the entire family unit, and consider the way leisure-time is negotiated among the adults within a household. Social change and increased awareness of the range of benefits of PA for women with children are additional strategies to be considered.

Nifty after fifty: evaluation of a physical activity directory for older people

Objective: To develop a physical activity directory (PAD) for Brisbane people over the age of 50 years for distribution by two methods (given or requested), and to determine its effectiveness in raising awareness and encouraging older people to participate in local physical activity options. Methods: Baseline demographic data and stage of change was collected from 224 participants who received the directory. Participants were interviewed by telephone six weeks later to determine their use of the directory on a number of dimensions. Results: Most participants interviewed at follow-up remembered reading the directory. Participants who requested the directory were significantly more likely than those who were given it to: be contemplators, read the directory, plan to ring a number, plan to attend a class, and to share the directory with others. Participants who were contemplators were significantly more likely to have participated in physical activity of their own and rang a number from the directory. The directory increased over half the participants' awareness of local physical activity options, yet only 7% reported ringing a number and 15% reported doing their own physical activity. Conclusions: The directory was more effective in raising awareness about physical activity options than encouraging people to participate in physical activity, and participants with short-term plans to be more active were more likely to have used the directory. Implications: The directory, even when linked with other services, raises awareness about physical activity options, but has minimal short-term influence on participation.