434 resultados para Physical interactions


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Background Low levels of physical activity and high levels of sedentary behavior (SB) are major public health concerns. This study was designed to develop and validate the 7-day Sedentary (S) and Light Intensity Physical Activity (LIPA) Log (7-day SLIPA Log), a self-report measure of specific daily behaviors. Method To develop the log, 62 specific SB and LIPA behaviors were chosen from the Compendium of Physical Activities. Face-to-face interviews were conducted with 32 sedentary volunteers to identify domains and behaviors of SB and LIPA. To validate the log, a further 22 sedentary adults were recruited to wear the GT3X for 7 consecutive days and nights. Results Pearson correlations (r) between the 7-day SLIPA Log and GT3X were significant for sedentary (r =.86, p < 0.001), for LIPA (r =.80, p < 0.001). Lying and sitting postures were positively correlated with GT3X output (r =.60 and r =.64, p < 0.001, respectively). No significant correlation was found for standing posture (r =.14, p = 0.53).The kappa values between the 7-day SLIPA Log and GT3X variables ranged from 0.09–0.61, indicating poor to good agreement. Conclusion The 7-day SLIPA Log is a valid self-report measure of SB and LIPA in specific behavioral domains.

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Social media tools are often the result of innovations in Information Technology and developed by IT professionals and innovators. Nevertheless, IT professionals, many of whom are responsible for designing and building social media technologies, have not been investigated on how they themselves use or experience social media for professional purposes. This study will use Information Grounds Theory (Pettigrew, 1998) as a framework to study IT professionals’ experience in using social media for professional purposes. Information grounds facilitates the opportunistic discovery of information within social settings created temporarily at a place where people gather for a specific purpose (e.g., doctors’ waiting rooms, office tea rooms etc.), but the social atmosphere stimulates spontaneous sharing of information (Pettigrew, 1999). This study proposes that social media has the qualities that make it a rich information grounds; people participate from separate “places” in cyberspace in a synchronous manner in real-time, making it almost as dynamic and unplanned as physical information grounds. There is limited research on how social media platforms are perceived as a “place,” (a place to go to, a place to gather, or a place to be seen in) that is comparable to physical spaces. There is also no empirical study on how IT professionals use or “experience” social media. The data for this study is being collected through a study of IT professionals who currently use Twitter. A digital ethnography approach is being taken wherein the researcher uses online observations and “follows” the participants online and observes their behaviours and interactions on social media. Next, a sub-set of participants will be interviewed on their experiences with and within social media and how social media compares with traditional methods of information grounds, information communication, and collaborative environments. An Evolved Grounded Theory (Glaser, 1992) approach will be used to analyse tweets data and interviews and to map the findings against the Information Ground Theory. Findings from this study will provide foundational understanding of IT professionals’ experiences within social media, and can help both professionals and researchers understand this fast-evolving method of communications.

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An estuary is formed at the mouth of a river where the tides meet a freshwater flow and it may be classified as a function of the salinity distribution and density stratification. An overview of the broad characteristics of the estuaries of South-East Queensland(Australia) is presented herein, where the small peri-urban estuaries may provide an useful indicator of potential changes which might occur in larger systems with growing urbanisation. Small peri-urban estuaries exhibits many key hydrological features and associated with ecosystem types of larger estuaries, albeit at smaller scales, often with a greater extent of urban development as a proportion of catchment area. We explore the potential for some smaller peri-urban estuaries to be used as natural laboratories to gain some much needed information on the estuarine processes, although any dynamics similarity is presently limited by critical absence of in-depth physical investigation in larger estuarine systems. The absence of the detailed turbulence and sedimentary data hampers the understanding and modelling of the estuarine zones. The interactions between the various stake holders are likely to define the vision for the future of South-East Queensland's peri-urban estuaries. This will require a solid understanding of the bio-physical function and capacity of the peri-urban estuaries. Based upon the knowledge gap, it is recommended that an adaptive trial and error approach be adopted for the future of investigation and management strategies.

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The boundaries between 'the digital' and our everyday physical world are dissolving as we develop more physical ways of interacting with computing. This forum presents some of the topics discussed in the colorful multidisciplinary field of tangible and embodied interaction

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The aims of this study were to examine: (1) the association between sociodemographic and lifestyle factors and sleep quality in a population-based cohort of Australian women and (2) possible influence of reproductive status and mental and physical health factors on these associations. Data on 3,655 women (mean age046.6 years, range 34.3–67.4) were obtained from the Mater Hospital University of Queensland Study of Pregnancy for this cross-sectional study. Self-rated sleep quality was assessed using the Pittsburgh Sleep Quality Index. For the purpose of this study, two cutoff points (scores 5 and 10) were used to divide women into three categories: normal (65.2 %), moderately poor (26.4 %), and very poor sleep quality (8.5 %). Other covariates were measured at 21-year follow-up as well. After adjusting for reproductive status, mental and physical health, there were significant associations between moderately poor sleep quality and education and between very poor sleep quality and unemployment, both measures of socioeconomic status. In addition, work-related exertion was associated with increased rates of moderately poor sleep quality, whereas those women undertaking moderate exercise were less likely to experience very poor sleep quality. Independent associations between sociodemographic factors and exercise with moderately poor and very poor sleep quality were identified. These findings demonstrate the dynamic nature of the association between exercise/exertion, socioeconomic status, and sleep quality and highlight the importance of taking these into consideration when dealing with issues of poor sleep quality in women.

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Targeting females at high school or earlier may be a key towards engaging them in science, technology, engineering and mathematics (STEM) education. This ethnographic study, part of a three-year longitudinal research project, investigated Year 8 female students’ learning about engineering concepts associated with designing, constructing, testing, and evaluating a catapult. There was a series of lead-up lessons and four lessons for the catapult challenge (total of 18 x 45-minute lessons) over a nine-week period. Data from two girls within a focus group showed that they needed to: (1) receive clarification on engineering terms to facilitate more fluent discourse, (2) question and debate conceptual understandings without peers being judgemental, and (3) have multiple opportunities for engaging with materials towards designing, constructing and explaining key concepts learnt. There are implications for teachers facilitating STEM education, such as: clarifying STEM terms, articulating how students can interact in non-judgmental ways, and providing multiple opportunities for interacting within engineering education.

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This thesis examines the characteristics of anthropometry and body composition in Indonesian adults and some of the risk factors including body image, eating behaviours, and physical activity. Examination on body image, eating behaviours, and physical activity demonstrates significant correlations with anthropometry and body composition in Indonesian adults. The study also identified body image distortion in some of the participants and provides suggestions for intervention development addressed to the groups of participants which have been identified as having a distorted body image.

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Flood flows in inundated urban environment constitute a natural hazard. During the 12- 13 January 2011 flood of the Brisbane River, detailed water elevation, velocity and suspended sediment data were recorded in an inundated street at the peak of the flood. The field observations highlighted a number of unusual flow interactions with the urban surroundings. These included some slow fluctuations in water elevations and velocity with distinctive periods between 50 and 100 s caused by some local topographic effect (choking), superposed with some fast turbulent fluctuations. The suspended sediment data highlighted some significant suspended sediment loads in the inundated zone.

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XRD (X-ray diffraction), XRF (X-ray fluorescence), TG (thermogravimetry), FT-IES (Fourier transform infrared emission spectroscopy), FESEM (field emission scanning electron microscope), TEM (transmission electron microscope) and nitrogen–adsorption–desorption analysis were used to characterize the composition and thermal evolution of the structure of natural goethite. The in situ FT-IES demonstrated the start temperature (250 °C) of the transformation of natural goethite to hematite and the thermodynamic stability of protohematite between 250 and 600 °C. The heated products showed a topotactic relationship to the original mineral based on SEM analysis. Finally, the nitrogen–adsorption–desorption isotherm provided the variation of surface area and pore size distribution as a function of temperature. The surface area displayed a remarkable increase up to 350 °C, and then decreased above this temperature. The significant increase in surface area was attributed to the formation of regularly arranged slit-shaped micropores running parallel to elongated direction of hematite microcrystal. The main pore size varied from 0.99 nm to 3.5 nm when heating temperature increases from 300 to 400 °C. The hematite derived from heating goethite possesses high surface area and favors the possible application of hematite as an adsorbent as well as catalyst carrier.

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Preventative health has become central to contemporary health care, identifying youth physical activity as a key factor in determining health and functioning. Schools offer a unique research setting due to distinctive methodological circumstances. However, school-based researchers face several obstacles in their endeavour to complete successful research investigations; often confronted with complex research designs and methodological procedures that are not easily amenable to school contexts. The purpose of this paper is to provide a practical guide for teachers (both teacher educators and teaching practitioners) seeking to conduct physical activity-based research in Australian school settings, as well as discuss research practices. The research enabling process has been divided into six phases: preparation; design; outcome measures; procedures; participants; and feedback. Careful planning and consideration must be undertaken prior to the commencement of, and during the research process, due to the complex nature of school settings and research processes that exist in the Australian context.

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In situ FT-IR spectroscopy allows the methanol synthesis reaction to be investigated under actual industrial conditions of 503 K and 10 MPa. On Cu/SiO2 catalyst formate species were initially formed which were subsequently hydrogenated to methanol. During the reaction a steady state concentration of formate species persisted on the copper. Additionally, a small quantity of gaseous methane was produced. In contrast, the reaction of CO2 and H2 on ZnO/SiO2 catalyst only resulted in the formation of zinc formate species: no methanol was detected. The interaction of CO2 and H2 with Cu/ZnO/SiO2 catalyst gave formate species on both copper and zinc oxide. Methanol was again formed by the hydrogenation of copper formate species. Steady-state concentrations of copper formate existed under actual industrial reaction conditions, and copper formate is the pivotal intermediate for methanol synthesis. Collation of these results with previous data on copper-based methanol synthesis catalysts allowed the formulation of a reaction mechanism

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FTIR spectra are reported of CO, CO2, H2 and H2O on silica-supported potassium, copper and potassium-copper catalysts. Adsorption of CO on a potassium/silica catalyst resulted in the formation of complexed CO moieties. Whereas exposure of CO2 to the same catalyst produced bands ascribed to CO2 -, bidentate carbonate and complexed CO species. Fully oxidised copper/silica surfaces gave bands due to CO on CuO and isolated Cu2+ cations on silica. Addition of potassium to this catalyst removed a peak attributed to CO adsorption on isolated Cu2+ cations and red-shifted the maximum ascribed to CO adsorbed on CuO. For a reduced copper/silica catalyst bands due to adsorbed CO on both high and low index planes were red-shifted by 10 cm-1 in the presence of potassium, although the strength of the Cu - CO bond did not appear to be increased concomitantly. An explanation in terms of an electrostatic effect between potassium and adsorbed CO is forwarded. A small maximum at ca. 1510 cm-1 for the reduced catalyst increased substantially upon exposing CO to a reoxidised promoted catalyst. Correspondingly, CO2 adsorption allowed the identification of two distinct carboxylate species, one of which was located at an interfacial site between copper and potassium oxide. Carboxylate species reacted with hydrogen at 295 K, on a reduced copper surface, to produce predominantly unidentate formate on potassium. In contrast no interaction was detected on a reoxidised copper catalyst at 295 K until a fraction of the copper surface was in a reduced state. Furthermore the interaction of polar water molecules with carboxylate species resulted in a perturbation of this structure which gave lower C----O stretching frequencies.

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Following the growing need for adoption of alternative fuels, this project aimed at getting more information on the oxidative potential of biodiesel particulate matter. Within this scope, the physical and chemical characteristics of biodiesel PM were analysed which lead to identification of reactive organic fractions. An in-house developed proflurescent nitroxide probe was used. This project further developed in-depth understanding of the chemical mechanisms following the detection of the oxidative potential of PM. This knowledge made a significant contribution to our understanding of processes behind negative health effects of pollution and enabled us to further develop new techniques to monitor it.

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FTIR spectra are reported of CO2 and COi/Hi on a silica-supported caesium-doped copper catalyst. Adsorption of COj on a "caesium"/silica surface resulted in the formation of COj and complexed CO species. Exposure of CO2 to' a caesium-doped reduced copper catalyst produced not only these species but also two forms of adsorbed carboxylate giving bands at 1550, 1510, 1365 and 1345 cm"1. Reaction of carboxylate species with hydrogen at 388 K gave formate species on copper and caesium oxide in addition to methoxy groups associated with caesium oxide. Methoxy species were not detected on undoped copper catalyst suggesting that caesium may be a promoter for the methanol synthesis reaction. Methanol decomposition on a caesium-doped copper catalyst produced a small number of formate species on copper and caesium oxide. Methoxy groups on caesium oxide decomposed to CO and U.2, and subsequent reaction between CO and adsorbed oxygen resulted in carboxylate formation. Methoxy species located at interfacial sites appeared to exhibit unusual adsorption properties.

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Raman and Fourier transform infrared (FT-IR) spectroscopy have been applied to a systematic investigation of the adsorption and decomposition of dichlorodifluoromethane (CCl2F2, CFC-12), fluorotrichloromethane (CCl3F, CFC-11), chlorodifluoromethane (CHClF2, HCFC-22) and molecular chlorine on oxide surfaces. Additionally, the effects of heating and ultraviolet photolysis of the CFC and HCFCs adsorbed on the oxide surfaces have been investigated. Spectral features for these species indicated a small wavenumber shift (1-6 cm-1) associated with the adsorbed phase. Some evidence, specifically the appearance of the Raman band at 507 cm-1, is presented to show that chlorine decomposition species are associated with these oxide surfaces. It was concluded that the new spectral feature (at ca. 507 cm-1) related with the decomposition of the CFC and HCFC molecules was an important indicator of the extent to which the reaction between the adsorbed CFC and HCFC and oxide surface has taken place. The extent of CFC-surface interaction has been quantified in terms of a maximum (Raman) frequency shift parameter (AM). Wavenumber shifts suggest both cation-adsorbate and non-specific adsorption interactions are occurring in the internal channels of the zeolites. Slow decomposition of the adsorbed CFCs under ultraviolet-visible photolysis (at ? > 300 nm) and/or thermal treatment was observed spectroscopically. Using FT-IR spectroscopy, the formation of gas-phase products (CO, CO2, HCl) both onyn photolysis and heating was evident. Results of these measurements are compared with the observed atmospheric reactivity of these compounds.