903 resultados para Regular Polygon


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The primary clinical role of the non-invasive physical measurement of a bone, generally referred to as ‘bone densitometry,’ is to identify those subjects at risk of an osteoporotic fracture and their subsequent response to pharmaceutical intervention. The true ‘gold standard’ measurement of the mechanical integrity of a bone, and hence its fracture load, is a destructive test, generally performed by compressing either a regular shaped sample or whole bone.

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This report uses data from the first two years of the CAUSEE study and focuses on the role of family in new business start-ups. While CAUSEE was not designed specifically to probe deeply into family matters the study does reveal interesting information on family orientated aspects including parental role models, family involvement on the start-up team, and family as a source of funding and advice. These findings can also be related to other information gathered as part of the comprehensive phone interviews that are used to gather the research data for CAUSEE. Furthermore we are also able to compare firm founders and 'Regular' nascent firm and young firm start-ups with their 'High Potential' counterparts in terms of their degrees of family involvement. Unless otherwise stated any differences or effects we comment on are 'statistically significant' at the five per cent level - that is, they are likely to reflect true differences or effects in the entire population of Australian start-ups.

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The demand for high quality rail services in the twenty-first century has put an ever increasing demand on all rail operators. In order to meet the expectation of their patrons, the maintenance regime of railway systems has to be tightened up, the track conditions have to be well looked after, the rolling stock must be designed to withstand heavy duty. In short, in an ideal world where resources are unlimited, one needs to implement a very rigorous inspection regime in order to take care of the modem needs of a railway system [1]. If cost were not an issue, the maintenance engineers could inspect the train body by the most up-to-date techniques such as ultra-sound examination, x-ray inspection, magnetic particle inspection, etc. on a regular basis. However it is inconceivable to have such a perfect maintenance regime in any commercial railway. Likewise, it is impossible to have a perfect rolling stock which can weather all the heavy duties experienced in a modem railway. Hence it is essential that some condition monitoring schemes are devised to pick up potential defects which could manifest into safety hazards. This paper introduces an innovative condition monitoring system for track profile and, together with an instrumented car to carry out surveillance of the track, will provide a comprehensive railway condition monitoring system which is free from the usual difficulty of electromagnetic compatibility issues in a typical railway environment

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Managing the sustainability of urban infrastructure requires regular health monitoring of key infrastructure such as bridges. The process of structural health monitoring involves monitoring a structure over a period of time using appropriate sensors, extracting damage sensitive features from the measurements made by the sensors, and analysing these features to determine the current state of the structure. Various techniques are available for structural health monitoring of structures, and acoustic emission is one technique that is finding an increasing use in the monitoring of civil infrastructures such as bridges. Acoustic emission technique is based on the recording of stress waves generated by rapid release of energy inside a material, followed by analysis of recorded signals to locate and identify the source of emission and assess its severity. This chapter first provides a brief background of the acoustic emission technique and the process of source localization. Results from laboratory experiments conducted to explore several aspects of the source localization process are also presented. The findings from the study can be expected to enhance knowledge of the acoustic emission process, and to aid the development of effective bridge structure diagnostics systems.

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Exclusion processes on a regular lattice are used to model many biological and physical systems at a discrete level. The average properties of an exclusion process may be described by a continuum model given by a partial differential equation. We combine a general class of contact interactions with an exclusion process. We determine that many different types of contact interactions at the agent-level always give rise to a nonlinear diffusion equation, with a vast variety of diffusion functions D(C). We find that these functions may be dependent on the chosen lattice and the defined neighborhood of the contact interactions. Mild to moderate contact interaction strength generally results in good agreement between discrete and continuum models, while strong interactions often show discrepancies between the two, particularly when D(C) takes on negative values. We present a measure to predict the goodness of fit between the discrete and continuous model, and thus the validity of the continuum description of a motile, contact-interacting population of agents. This work has implications for modeling cell motility and interpreting cell motility assays, giving the ability to incorporate biologically realistic cell-cell interactions and develop global measures of discrete microscopic data.

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For the fabrication of tissue engineering scaffolds, the intended tissue formation process imposes requirements on the architecture. The chosen porosity often is a tradeoff between volume and surface area accessible to cells, and mechanical properties of the construct. Interconnectivity of the pores is essential for cell migration through the scaffold and for mass transport. Conventional techniques such as salt leaching often result in heterogeneous structures and do not allow for a precise control of the architecture. Stereolithography is a rapid prototyping method that can be utilised to make 3D constructs with high spatial control by radical photopolymerisation. In this study, a regular structure based on cyclic repetition of cell units were designed through CAD modelling.. One of these structures was built on a stereolithography apparatus (SLA). Furthermore, a polylactide-based resin was developed that can be applied in stereolithography. Polylactide has proven before to be a well-performing polymer in bone tissue engineering. The final objective in this study is to build newly designed PDLLA scaffolds with a precise SLA fabrication technique to study the effect of scaffold architecture on mechanical and biological properties.

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Background: Palliative care should be provided according to the individual needs of the patient, caregiver and family, so that the type and level of care provided, as well as the setting in which it is delivered, are dependent on the complexity and severity of individual needs, rather than prognosis or diagnosis. This paper presents a study designed to assess the feasibility and efficacy of an intervention to assist in the allocation of palliative care resources according to need, within the context of a population of people with advanced cancer. ---------- Methods/design: People with advanced cancer and their caregivers completed bi-monthly telephone interviews over a period of up to 18 months to assess unmet needs, anxiety and depression, quality of life, satisfaction with care and service utilisation. The intervention, introduced after at least two baseline phone interviews, involved a) training medical, nursing and allied health professionals at each recruitment site on the use of the Palliative Care Needs Assessment Guidelines and the Needs Assessment Tool: Progressive Disease - Cancer (NAT: PD-C); b) health professionals completing the NAT: PD-C with participating patients approximately monthly for the rest of the study period. Changes in outcomes will be compared pre-and post-intervention.---------- Discussion: The study will determine whether the routine, systematic and regular use of the Guidelines and NAT: PD-C in a range of clinical settings is a feasible and effective strategy for facilitating the timely provision of needs based care.

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Aim Australian residential aged care does not have a system of quality assessment related to clinical outcomes, or comprehensive quality benchmarking. The Residential Care Quality Assessment was developed to fill this gap; and this paper discusses the process by which preliminary benchmarks representing high and low quality were developed for it. Methods Data were collected from all residents (n = 498) of nine facilities. Numerator–denominator analysis of clinical outcomes occurred at a facility-level, with rank-ordered results circulated to an expert panel. The panel identified threshold scores to indicate excellent and questionable care quality, and refined these through Delphi process. Results Clinical outcomes varied both within and between facilities; agreed thresholds for excellent and poor outcomes were finalised after three Delphi rounds. Conclusion Use of the Residential Care Quality Assessment provides a concrete means of monitoring care quality and allows benchmarking across facilities; its regular use could contribute to improved care outcomes within residential aged care in Australia.

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Tobacco yellow dwarf virus (TbYDV, family Geminiviridae, genus Mastrevirus) is an economically important pathogen causing summer death and yellow dwarf disease in bean (Phaseolus vulgaris L.) and tobacco (Nicotiana tabacum L.), respectively. Prior to the commencement of this project, little was known about the epidemiology of TbYDV, its vector and host-plant range. As a result, disease control strategies have been restricted to regular poorly timed insecticide applications which are largely ineffective, environmentally hazardous and expensive. In an effort to address this problem, this PhD project was carried out in order to better understand the epidemiology of TbYDV, to identify its host-plant and vectors as well as to characterise the population dynamics and feeding physiology of the main insect vector and other possible vectors. The host-plants and possible leafhopper vectors of TbYDV were assessed over three consecutive growing seasons at seven field sites in the Ovens Valley, Northeastern Victoria, in commercial tobacco and bean growing properties. Leafhoppers and plants were collected and tested for the presence of TbYDV by PCR. Using sweep nets, twenty-three leafhopper species were identified at the seven sites with Orosius orientalis the predominant leafhopper. Of the 23 leafhopper species screened for TbYDV, only Orosius orientalis and Anzygina zealandica tested positive. Forty-two different plant species were also identified at the seven sites and tested. Of these, TbYDV was only detected in four dicotyledonous species, Amaranthus retroflexus, Phaseolus vulgaris, Nicotiana tabacum and Raphanus raphanistrum. Using a quadrat survey, the temporal distribution and diversity of vegetation at four of the field sites was monitored in order to assess the presence of, and changes in, potential host-plants for the leafhopper vector(s) and the virus. These surveys showed that plant composition and the climatic conditions at each site were the major influences on vector numbers, virus presence and the subsequent occurrence of tobacco yellow dwarf and bean summer death diseases. Forty-two plant species were identified from all sites and it was found that sites with the lowest incidence of disease had the highest proportion of monocotyledonous plants that are non hosts for both vector and the virus. In contrast, the sites with the highest disease incidence had more host-plant species for both vector and virus, and experienced higher temperatures and less rainfall. It is likely that these climatic conditions forced the leafhopper to move into the irrigated commercial tobacco and bean crop resulting in disease. In an attempt to understand leafhopper species diversity and abundance, in and around the field borders of commercially grown tobacco crops, leafhoppers were collected from four field sites using three different sampling techniques, namely pan trap, sticky trap and sweep net. Over 51000 leafhopper samples were collected, which comprised 57 species from 11 subfamilies and 19 tribes. Twentythree leafhopper species were recorded for the first time in Victoria in addition to several economically important pest species of crops other than tobacco and bean. The highest number and greatest diversity of leafhoppers were collected in yellow pan traps follow by sticky trap and sweep nets. Orosius orientalis was found to be the most abundant leafhopper collected from all sites with greatest numbers of this leafhopper also caught using the yellow pan trap. Using the three sampling methods mentioned above, the seasonal distribution and population dynamics of O. orientalis was studied at four field sites over three successive growing seasons. The population dynamics of the leafhopper was characterised by trimodal peaks of activity, occurring in the spring and summer months. Although O. orientalis was present in large numbers early in the growing season (September-October), TbYDV was only detected in these leafhoppers between late November and the end of January. The peak in the detection of TbYDV in O. orientalis correlated with the observation of disease symptoms in tobacco and bean and was also associated with warmer temperatures and lower rainfall. To understand the feeding requirements of Orosius orientalis and to enable screening of potential control agents, a chemically-defined artificial diet (designated PT-07) and feeding system was developed. This novel diet formulation allowed survival for O. orientalis for up to 46 days including complete development from first instar through to adulthood. The effect of three selected plant derived proteins, cowpea trypsin inhibitor (CpTi), Galanthus nivalis agglutinin (GNA) and wheat germ agglutinin (WGA), on leafhopper survival and development was assessed. Both GNA and WGA were shown to reduce leafhopper survival and development significantly when incorporated at a 0.1% (w/v) concentration. In contrast, CpTi at the same concentration did not exhibit significant antimetabolic properties. Based on these results, GNA and WGA are potentially useful antimetabolic agents for expression in genetically modified crops to improve the management of O. orientalis, TbYDV and the other pathogens it vectors. Finally, an electrical penetration graph (EPG) was used to study the feeding behaviour of O. orientalis to provide insights into TbYDV acquisition and transmission. Waveforms representing different feeding activity were acquired by EPG from adult O. orientalis feeding on two plant species, Phaseolus vulgaris and Nicotiana tabacum and a simple sucrose-based artificial diet. Five waveforms (designated O1-O5) were observed when O. orientalis fed on P. vulgaris, while only four (O1-O4) and three (O1-O3) waveforms were observed during feeding on N. tabacum and the artificial diet, respectively. The mean duration of each waveform and the waveform type differed markedly depending on the food source. This is the first detailed study on the tritrophic interactions between TbYDV, its leafhopper vector, O. orientalis, and host-plants. The results of this research have provided important fundamental information which can be used to develop more effective control strategies not only for O. orientalis, but also for TbYDV and other pathogens vectored by the leafhopper.

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Assessment for Learning(AfL) case studies in a North Queensland school highlight the significance of the teacher-student relationship in creating a supportive culture within which students can negotiate new learner identities. AfL practices are school based evaluative practices that occur within the regular flow of teaching and learning with the purpose of informing and improving student learning to enhance learner autonomy. The identity of an autonomous learner is socially negotiated through participation in the community of practice of the class. Underpinned by a sociocultural perspective this research shows how AfL is manifested in action in its complexity and how positive teacher-student interactions can build bridges for students to move towards full participation.

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The purpose of this investigation was to undertake pilot research to develop an understanding of the current culture of older Australian women’s (35-50 years) drinking behaviour from a uniquely female perspective. Methods Two separate focus group interviews were undertaken with women (N = 11) aged between 35 and 50 years living in South-East Queensland, Australia. Women were asked to openly discuss how and why they drink alcohol (ie., their regular drinking behaviour), how this has changed over time, and the attitudes and values that influence their behaviour. Results Participants reported that their consumption of alcohol was more regulated and controlled and although some women drank more frequently, the quantity consumed at each drinking occasion had decreased significantly. Occasional consumption of large amounts of alcohol tended to be the result of ‘incidental drinking’ as opposed to ‘determined drinking’. The reasons for alcohol consumption were found to be internal as well as social. Internal reasons included stress relief, increased relaxation and self reward. Further, alcohol was used as a social lubricant. This cohort also reported being influenced by the drinking patterns of their partners. Social group matching was however found to have a negative impact on alcohol consumption as social groups most commonly endorsed lesser levels of intoxication. Further, the women reported that they were of an age in which they felt excessive drinking to be ‘undignified’. Personal reasons such as vocational and family responsibilities further modified the levels of consumption for individual women. Finally, it was reported that perceived health risks that can result from excessive and/or repetitive drinking led to a decreased in consumption. Conclusion It is proposed that the findings of this investigation could be used to improve current knowledge regarding more mature women’s drinking culture, associated risks and risk prevention strategies.

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There is widespread recognition that higher education institutions (HEIs) must actively support commencing students to ensure equity in access to the opportunities afforded by higher education. This role is particularly critical for students who because of educational, cultural or financial disadvantage or because they are members of social groups currently under-represented in higher education, may require additional transitional support to “level the playing field.” The challenge faced by HEIs is to provide this “support” in a way that is integrated into regular teaching and learning practices and reaches all commencing students. The Student Success Program (SSP) is an intervention in operation at the Queensland University of Technology (QUT) designed to identify and support those students deemed to be at risk of disengaging from their learning and their institution. Two sets of evidence of the impact of the SSP are presented: First, its expansion (a) from a one-faculty pilot project (Nelson, Duncan & Clarke, 2009) to all faculties and (b) into a variety of applications mirroring the student life cycle; and second, an evaluation of the impact of the SSP on students exposed to it. The outcomes suggest that: the SSP is an example of good practice that can be successfully applied to a variety of learning contexts and student enrolment situations; and the impact of the intervention on student persistence is sustained for at least 12 months and positively influences student retention. It is claimed that the good practice evidenced by the SSP is dependent on its integration into the broader First Year Experience Program at QUT as an example of transition pedagogy in action.

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The public transport corridor bordering the study site runs NW to SE and is perceived as a source of noise and pollution. The key urban planning strategies adopted by this team were: • Acoustic separation from transport corridor noise source, • A regular grid pattern of urban blocks, and • A clear hierarchy of accessible open space throughout the development.

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In recent years there has been widespread interest in patterns, perhaps provoked by a realisation that they constitute a fundamental brain activity and underpin many artificial intelligence systems. Theorised concepts of spatial patterns including scale, proportion, and symmetry, as well as social and psychological understandings are being revived through digital/parametric means of visualisation and production. The effect of pattern as an ornamental device has also changed from applied styling to mediated dynamic effect. The interior has also seen patterned motifs applied to wall coverings, linen, furniture and artefacts with the effect of enhancing aesthetic appreciation, or in some cases causing psychological and/or perceptual distress (Rodemann 1999). ----- ----- While much of this work concerns a repeating array of surface treatment, Philip Ball’s The Self- Made Tapestry: Pattern Formation in Nature (1999) suggests a number of ways that patterns are present at the macro and micro level, both in their formation and disposition. Unlike the conventional notion of a pattern being the regular repetition of a motif (geometrical or pictorial) he suggests that in nature they are not necessarily restricted to a repeating array of identical units, but also include those that are similar rather than identical (Ball 1999, 9). From his observations Ball argues that they need not necessarily all be the same size, but do share similar features that we recognise as typical. Examples include self-organized patterns on a grand scale such as sand dunes, or fractal networks caused by rivers on hills and mountains, through to patterns of flow observed in both scientific experiments and the drawings of Leonardo da Vinci.

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Introduction: There are many low intensity (LI) cognitive behavoural therapy (CBT) solutions to the problem of limited service access. In this chapter, we aim to discuss a relatively low-technology approach to access using standard postal services-CBT by mail, or M-CBT. Bibliotherapies including M-CBT teach key concepts and self-management techniques, together with screening tools and forms to structure home practice. M-CBT differs from other bibliotherapies by segmenting interventions and mailing them at regular intervals. Most involve participants returning copies of monitoring forms or completed handouts. Therapist feedback is provided, often in personal letters that accompany the printed materials. Participants may also be given access to telephone or email support. ----- ----- M-CBT clearly fulfills criteria for an LI CBT (see Bennett-Levy et al., Chapter 1, for a definition of LI interventions). Once written, they involve little therapist time and rely heavily on self-management. However, content and overall treatment duration need not be compromised. Long-term interventions with multiple components can be delivered via this method, provided their content can be communicated in letters and engagement is maintained.