967 resultados para experimental methodology


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Aim. A protocol for a new peer-led self-management programme for communitydwelling older people with diabetes in Shanghai, China. Background. The increasing prevalence of type 2 diabetes poses major public health challenges. Appropriate education programmes could help people with diabetes to achieve self-management and better health outcomes. Providing education programmes to the fast growing number of people with diabetes present a real challenge to Chinese healthcare system, which is strained for personnel and funding shortages. Empirical literature and expert opinions suggest that peer education programmes are promising. Design. Quasi-experimental. Methods. This study is a non-equivalent control group design (protocol approved in January, 2008). A total of 190 people, with 95 participants in each group, will be recruited from two different, but similar, communities. The programme, based on Social Cognitive Theory, will consist of basic diabetes instruction and social support and self-efficacy enhancing group activities. Basic diabetes instruction sessions will be delivered by health professionals, whereas social support and self-efficacy enhancing group activities will be led by peer leaders. Outcome variables include: self-efficacy, social support, self-management behaviours, depressive status, quality of life and healthcare utilization, which will be measured at baseline, 4 and 12 weeks. Discussion. This theory-based programme tailored to Chinese patients has potential for improving diabetes self-management and subsequent health outcomes. In addition, the delivery mode, through involvement of peer leaders and existing community networks,is especially promising considering healthcare resource shortage in China.

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Ethnography is now a well-established research methodology for virtual environments, and the vast majority of accounts have one aspect in common, whether textual or graphic environments – that of the embodied avatar. In this article, I first discuss the applicability of such a methodology to non-avatar environments such as Eve Online, considering where the methodology works and the issues that arise in its implementation – particularly for the consideration of sub-communities within the virtual environment. Second, I consider what alternative means exist for getting at the information that is obtained through an ethnographic study of the virtual environment. To that end, I consider the practical and ethical implications of utilizing existing accounts, the importance of the meta-game discourse, including those sources outside of the control of the environment developer, and finally the utility in combining personal observations with accounts of other ethnographers, both within and between environments.

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This case-study explores alternative and experimental methods of research data acquisition, through an emerging research methodology, ‘Guerrilla Research Tactics’ [GRT]. The premise is that the researcher develops covert tactics for attracting and engaging with research participants. These methods range between simple analogue interventions to physical bespoke artefacts which contain an embedded digital link to a live, interactive data collecting resource, such as an online poll, survey or similar. These artefacts are purposefully placed in environments where the researcher anticipates an encounter and response from the potential research participant. The choice of design and placement of artefacts is specific and intentional. DESCRIPTION: Additional information may include: the outcomes; key factors or principles that contribute to its effectiveness; anticipated impact/evidence of impact. This case-study assesses the application of ‘Guerrilla Research Tactics’ [GRT] Methodology as an alternative, engaging and interactive method of data acquisition for higher degree research. Extending Gauntlett’s definition of ‘new creative methods… an alternative to language driven qualitative research methods' (2007), this case-study contributes to the existing body of literature addressing creative and interactive approaches to HDR data collection. The case-study was undertaken with Masters of Architecture and Urban Design research students at QUT, in 2012. Typically students within these creative disciplines view research as a taxing and boring process, distracting them from their studio design focus. An obstacle that many students face, is acquiring data from their intended participant groups. In response to these challenges the authors worked with students to develop creative, fun, and engaging research methods for both the students and their research participants. GRT are influenced by and developed from a combination of participatory action research (Kindon, 2008) and unobtrusive research methods (Kellehear, 1993), to enhance social research. GRT takes un-obtrusive research in a new direction, beyond the typical social research methods. The Masters research students developed alternative methods for acquiring data, which relied on a combination of analogue design interventions and online platforms commonly distributed through social networks. They identified critical issues that required action by the community, and the processes they developed focused on engaging with communities, to propose solutions. Key characteristics shared between both GRT and Guerrilla Activism, are notions of political issues, the unexpected, the unconventional, and being interactive, unique and thought provoking. The trend of Guerrilla Activism has been adapted to: marketing, communication, gardening, craftivism, theatre, poetry, and art. Focusing on the action element and examining elements of current trends within Guerrilla marketing, we believe that GRT can be applied to a range of research areas within various academic disciplines.

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High resolution TEM images of boron carbide (B13C2) have been recorded and compared with images calculated using the multislice method as implemented by M. A. O'Keefe in the SHRLI programs. Images calculated for the [010] zone, using machine parameters for the JEOL 2000FX AEM operating at 200 keV, indicate that for the structure model of Will et al., the optimum defocus image can be interpreted such that white spots correspond to B12 icosahedra for thin specimens and to low density channels through the structure adjacent to the direct inter-icosahedral bonds for specimens of intermediate thickness (-40 > t > -100 nm). With this information, and from the symmetry observed in the TEM images, it is likely that the (101) twin plane passes through the center of icosahedron located at the origin. This model was tested using the method of periodic continuation. Resulting images compare favorably with experimental images, thus supporting the structural model. The introduction of a (101) twin plane through the origin creates distortions to the icosahedral linkages as well as to the intra-icosahedral bonding. This increases the inequivalence of adjacent icosahedral sites along the twin plane, and thereby increases the likelihood of bipolaron hopping.

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This discussion has outlined a theoretical and pragmatic framework to demonstrate that future research involving the analysis of human performance in surgical should encourage the use of phenomenology to enhance the knowledge base of this area of study. Merging experiential (first-person) and experimental (third-person) methods may possibly help improve research designs and analyses in the investigation of robotics in surgical performance. By relying solely on third-person techniques, the current methodology and interpretation used to analyze human performance in surgical robotics is limited. Recent advances in cognitive science and psychology have also recognized this limitation and have now begun to shift to neurophenomenology. Finally, discussion on recent robotics research presented here demonstrates the potential phenomenology holds for augmenting the methodological and analysis techniques currently used by researchers of human performance in surgical robotics.

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A critical step in the dissemination of ovarian cancer is the formation of multicellular spheroids from cells shed from the primary tumour. The objectives of this study were to apply bioengineered three-dimensional (3D) microenvironments for culturing ovarian cancer spheroids in vitro and simultaneously to build on a mathematical model describing the growth of multicellular spheroids in these biomimetic matrices. Cancer cells derived from human epithelial ovarian carcinoma were embedded within biomimetic hydrogels of varying stiffness and grown for up to 4 weeks. Immunohistochemistry, imaging and growth analyses were used to quantify the dependence of cell proliferation and apoptosis on matrix stiffness, long-term culture and treatment with the anti-cancer drug paclitaxel. The mathematical model was formulated as a free boundary problem in which each spheroid was treated as an incompressible porous medium. The functional forms used to describe the rates of cell proliferation and apoptosis were motivated by the experimental work and predictions of the mathematical model compared with the experimental output. This work aimed to establish whether it is possible to simulate solid tumour growth on the basis of data on spheroid size, cell proliferation and cell death within these spheroids. The mathematical model predictions were in agreement with the experimental data set and simulated how the growth of cancer spheroids was influenced by mechanical and biochemical stimuli including matrix stiffness, culture duration and administration of a chemotherapeutic drug. Our computational model provides new perspectives on experimental results and has informed the design of new 3D studies of chemoresistance of multicellular cancer spheroids.

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The INEX 2011 Relevance Feedback track offered a refined approach to the evaluation of Focused Relevance Feedback algorithms through simulated exhaustive user feedback. Run in largely identical fashion to the Relevance Feedback track in INEX 2010[2], we simulated a user-in-the loop by re-using the assessments of ad-hoc retrieval obtained from real users who assess focused ad-hoc retrieval submissions. We present the evaluation methodology, its implementation, and experimental results obtained for four submissions from two participating organisations. As the task and evaluation methods did not change between INEX 2010 and now, explanations of these details from the INEX 2010 version of the track have been repeated verbatim where appropriate.

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News blog hot topics are important for the information recommendation service and marketing. However, information overload and personalized management make the information arrangement more difficult. Moreover, what influences the formation and development of blog hot topics is seldom paid attention to. In order to correctly detect news blog hot topics, the paper first analyzes the development of topics in a new perspective based on W2T (Wisdom Web of Things) methodology. Namely, the characteristics of blog users, context of topic propagation and information granularity are unified to analyze the related problems. Some factors such as the user behavior pattern, network opinion and opinion leader are subsequently identified to be important for the development of topics. Then the topic model based on the view of event reports is constructed. At last, hot topics are identified by the duration, topic novelty, degree of topic growth and degree of user attention. The experimental results show that the proposed method is feasible and effective.

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Standard differential equation–based models of collective cell behaviour, such as the logistic growth model, invoke a mean–field assumption which is equivalent to assuming that individuals within the population interact with each other in proportion to the average population density. Implementing such assumptions implies that the dynamics of the system are unaffected by spatial structure, such as the formation of patches or clusters within the population. Recent theoretical developments have introduced a class of models, known as moment dynamics models, which aim to account for the dynamics of individuals, pairs of individuals, triplets of individuals and so on. Such models enable us to describe the dynamics of populations with clustering, however, little progress has been made with regard to applying moment dynamics models to experimental data. Here, we report new experimental results describing the formation of a monolayer of cells using two different cell types: 3T3 fibroblast cells and MDA MB 231 breast cancer cells. Our analysis indicates that the 3T3 fibroblast cells are relatively motile and we observe that the 3T3 fibroblast monolayer forms without clustering. Alternatively, the MDA MB 231 cells are less motile and we observe that the MDA MB 231 monolayer formation is associated with significant clustering. We calibrate a moment dynamics model and a standard mean–field model to both data sets. Our results indicate that the mean–field and moment dynamics models provide similar descriptions of the 3T3 fibroblast monolayer formation whereas these two models give very different predictions for the MDA MD 231 monolayer formation. These outcomes indicate that standard mean–field models of collective cell behaviour are not always appropriate and that care ought to be exercised when implementing such a model.

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We sought to determine the impact of electrospinning parameters on a trustworthy criterion that could evidently improve the maximum applicability of fibrous scaffolds for tissue regeneration. We used an image analysis technique to elucidate the web permeability index (WPI) by modeling the formation of electrospun scaffolds. Poly(3-hydroxybutyrate) (P3HB) scaffolds were fabricated according to predetermined conditions of levels in a Taguchi orthogonal design. The material parameters were the polymer concentration, conductivity, and volatility of the solution. The processing parameters were the applied voltage and nozzle-to-collector distance. With a law to monitor the WPI values when the polymer concentration or the applied voltage was increased, the pore interconnectivity was decreased. The quality of the jet instability altered the pore numbers, areas, and other structural characteristics, all of which determined the scaffold porosity and aperture interconnectivity. An initial drastic increase was observed in the WPI values because of the chain entanglement phenomenon above a 6 wt % P3HB content. Although the solution mixture significantly (p < 0.05) changed the scaffold architectural characteristics as a function of the solution viscosity and surface tension, it had a minor impact on the WPI values. The solution mixture gained the third place of significance, and the distance was approved as the least important factor.

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Purpose: The measurement of broadband ultrasonic attenuation (BUA) in cancellous bone for the assessment of osteoporosis follows a parabolic-type dependence with bone volume fraction; having minima values corresponding to both entire bone and entire marrow. Langton has recently proposed that the primary BUA mechanism may be significant phase interference due to variations in propagation transit time through the test sample as detected over the phase-sensitive surface of the receive ultrasound transducer. This fundamentally simple concept assumes that the propagation of ultrasound through a complex solid : liquid composite sample such as cancellous bone may be considered by an array of parallel ‘sonic rays’. The transit time of each ray is defined by the proportion of bone and marrow propagated, being a minimum (tmin) solely through bone and a maximum (tmax) solely through marrow. A Transit Time Spectrum (TTS), ranging from tmin to tmax, may be defined describing the proportion of sonic rays having a particular transit time, effectively describing lateral inhomogeneity of transit time over the surface of the receive ultrasound transducer. Phase interference may result from interaction of ‘sonic rays’ of differing transit times. The aim of this study was to test the hypothesis that there is a dependence of phase interference upon the lateral inhomogenity of transit time by comparing experimental measurements and computer simulation predictions of ultrasound propagation through a range of relatively simplistic solid:liquid models exhibiting a range of lateral inhomogeneities. Methods: A range of test models was manufactured using acrylic and water as surrogates for bone and marrow respectively. The models varied in thickness in one dimension normal to the direction of propagation, hence exhibiting a range of transit time lateral inhomogeneities, ranging from minimal (single transit time) to maximal (wedge; ultimately the limiting case where each sonic ray has a unique transit time). For the experimental component of the study, two unfocused 1 MHz ¾” broadband diameter transducers were utilized in transmission mode; ultrasound signals were recorded for each of the models. The computer simulation was performed with Matlab, where the transit time and relative amplitude of each sonic ray was calculated. The transit time for each sonic ray was defined as the sum of transit times through acrylic and water components. The relative amplitude considered the reception area for each sonic ray along with absorption in the acrylic. To replicate phase-sensitive detection, all sonic rays were summed and the output signal plotted in comparison with the experimentally derived output signal. Results: From qualtitative and quantitative comparison of the experimental and computer simulation results, there is an extremely high degree of agreement of 94.2% to 99.0% between the two approaches, supporting the concept that propagation of an ultrasound wave, for the models considered, may be approximated by a parallel sonic ray model where the transit time of each ray is defined by the proportion of ‘bone’ and ‘marrow’. Conclusions: This combined experimental and computer simulation study has successfully demonstrated that lateral inhomogeneity of transit time has significant potential for phase interference to occur if a phase-sensitive ultrasound receive transducer is implemented as in most commercial ultrasound bone analysis devices.

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A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.

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The appearance of poststructuralism as a research methodology in public health literature raises questions about the history and purpose of this research. We examine (a) some aspects of the history of qualitative methods and their place within larger social and research domains, and (b) the purposes of a public health research that employs poststructuralist philosophy delineating the methodological issues that require consideration in positing a poststructural analysis. We argue against poststructuralism becoming a research methodology deployed to seize the pubic health debate, rather than being employed for its own particular critical strengths.

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Light Gauge Steel Framing (LSF) walls made of cold-formed and thin-walled steel lipped channel studs with plasterboard linings on both sides are commonly used in commercial, industrial and residential buildings. However, there is limited data about their structural and thermal performance under fire conditions while past research showed contradicting results about the benefits of using cavity insulation. A new composite wall panel was recently proposed to improve the fire resistance rating of LSF walls, where an insulation layer was used externally between the plasterboards on both sides of the wall frame instead of using it in the cavity. In this research 11 full scale tests were conducted on conventional load bearing steel stud walls with and without cavity insulation, and the new composite panel system to study their thermal and structural performance under standard fire conditions. These tests showed that the use of cavity insulation led to inferior fire performance of walls, and provided supporting research data. They demonstrated that the use of insulation externally in a composite panel enhanced the thermal and structural performance of LSF walls and increased their fire resistance rating. This paper presents the details of the LSF wall tests and the thermal and structural performance data and fire resistance rating of load-bearing wall assemblies lined with varying plasterboard-insulation configurations under two different load ratios. Fire test results including the time–temperature and deflection profiles are presented along with the failure times and modes.

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This thesis advances the knowledge of behavioural economics on the importance of individual characteristics – such as gender, personality or culture – for choices relevant to labour and insurance markets. It does so using economic experiments, survey tools and physiological data, collected in economic laboratories and in the field. More specifically, the thesis includes 5 experimental economic studies investigating individual-specific characteristics (gender, age, personality, cultural background) in decisions influenced by risk attitudes and social preferences. One of these characteristics is the physiological state of decision-makers, measured by heart rate variability. The results show that individual-specific characteristics play an important role for choices affected by social preferences, a finding to a lesser degree observable for risk preferences. This finding is confirmed under revealed incentivised choices and when studying (latent) physiological responses of decision-makers.