944 resultados para Behaviour changes
Resumo:
Over the last two decades fundamental changes have taken place in the global supply and local structure of provision of British food retailing. Consumer lifestyles have also changed markedly. Despite some important studies of local interactions between new retail developments and consumers, we argue in this paper that there is a critical need to gauge the cumulative effects of these changes on consumer behaviour over longer periods. In this, the first of two papers, we present the main findings of a study of the effects of long-term retail change on consumers at the local level. We provide in this paper an overview of the changing geography of retail provision and patterns of consumption at the local level. We contextualise the Portsmouth study area as a locality that typifies national changes in retail provision and consumer lifestyles; outline the main findings of two large-scale surveys of food shopping behaviour carried out in 1980 and 2002; and reveal the impacts of retail restructuring on consumer behaviour. We focus in particular on choice between stores at the local level and end by problematising our understanding of how consumers experience choice, emphasising the need for qualitative research. This issue is then dealt with in our complementary second paper, which explores choice within stores and how this relates to the broader spatial context.
Resumo:
Background & objectives Several neurodevelopmental disorders are associated with resistance to change and challenging behaviours – including temper outbursts – that ensue following changes to routines, plans or expectations (here, collectively: expectations). Here, a change signalling intervention was tested for proof of concept and potential practical effectiveness. Methods Twelve individuals with Prader-Willi syndrome participated in researcher- and caregiver-led pairing of a distinctive visual-verbal signal with subsequent changes to expectations. Specific expectations for a planned subset of five participants were systematically observed in minimally manipulated natural environments. Nine caregivers completed a temper outburst diary during a four week baseline period and a two week signalling evaluation period. Results Participants demonstrated consistently less temper outburst behaviour in the systematic observations when changes imposed to expectations were signalled, compared to when changes were not signalled. Four of the nine participants whose caregivers completed the behaviour diary demonstrated reliable reductions in temper outbursts between baseline and signalling evaluation. Limitations An active control group for the present initial evaluation of the signalling strategy using evidence from caregiver behaviour diaries was outside the scope of the present pilot study. Thus, findings cannot support the clinical efficacy of the present signalling approach. Conclusions Proof of concept evidence that reliable pairing of a distinctive cue with a subsequent change to expectation can reduce associated challenging behaviour is provided. Data provide additional support for the importance of specific practical steps in further evaluations of the change signalling approach.
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The crystallisation behaviour for alloys in the Al-rich corner in the Al-La-Ni system is reported in this paper Alloys were selected based on the topological instability criterion (lambda criterion) calculated from the alloy composition and metallic radii of the alloying elements and aluminum Amorphous ribbons were produced by melt-spinning and the crystallisation reactions were analysed by X-ray diffraction and calorimetry The results showed that increasing the values of lambda from 0.072 to 0.16 resulted in the following changes in the crystallisation behaviour, as predicted by the lambda criterion (a) nanocrystallisation of alpha-Al for the alloy composition corresponding to lambda = 0 072 and (b) detection of the glass transition temperature, T(g), for the alloys with composition close to lambda approximate to 0.1 line. For compositions corresponding to both ends of the lambda approximate to 0 1 line (near the binaries lines) T(g) could be detected only in the ""intermediary"" central region, and the alloy we produced in this region was considered the best glass former for the Al-rich corner Also, except for the alloys with the highest NI content, crystallisation proceeded by two distinct exothermic peaks which are typical of nanocrystallisation transformation. These behaviours are discussed in terms of compositional (lambda parameter) and topological aspects to account for cluster formation in the amorphous phase. Crown Copyright (C) 2009 Published by Elsevier B V All rights reserved
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The dynamic plastic response of a simply supported circular plate is analysed. Emphasis is given to the plate behaviour after it has broken free from the supports due to a local material failure. The theoretical rigid plastic analysis predicts various features of the response such as the time to failure, residual kinetic energy and the critical velocity at failure. The residual kinetic energy of the plate could be significant enough to cause secondary impact damage. It is shown that the shape of the plate changes after breaking free from the supports, which is important for forensic investigations. The solution for various cases were proven to be exact in the context of the upper and lower bounds theorems of the theory of plasticity. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
Aluminium alloy (AA) 2024-T3 is an important engineering material due to its widespread use in the aerospace industry. However, it is very prone to localized corrosion attack in chloride containing media, which has been mainly associated to the presence of coarse intermetallics (IMs) in its microstructure. In this work the corrosion behaviour of AA 2024-T3 in low concentrated chloride media was investigated using microscopy and electrochemical methods. TEM/EDS observations on non-corroded samples evidenced the heterogeneous composition within the IMs. In addition, SEM observations showed that intermetallics with the same nominal composition present different reactivity, and that both types of coarse IMs normally found in the alloy microstructure are prone to corrosion. Moreover, EDS analyses showed important compositional changes in corroded IMs, evidencing a selective dissolution of their more active constituents, and the onset of an intense oxygen peak, irrespective to the IM nature, indicating the formation of corrosion products. On the other hand, the results of the electrochemical investigations, in accordance with the SEM/EDS observations, evidenced that IMs corrosion dominates the electrochemical response of the alloy during the first hours of immersion in the test electrolyte. (c) 2008 Elsevier Ltd. All rights reserved.
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Diachronic approaches provide potential for a more sophisticated framework within which to examine change in Neanderthal behavioural complexity using archaeological proxies such as symbolic artefacts, faunal assemblages and technology. Analysis of the temporal appearance and distribution of such artefacts and assemblages provide the basis for identifying changes in Neanderthal behavioural complexity in terms of symbolism, faunal extraction and technology respectively. Although changes in technology and faunal extraction were examined in the wider study, only the results of the symbolic study are presented below to illustrate the potential of the approach.
Resumo:
Changes in the physical properties (such as particle density, bulk density of the bed, shrinkage and bed porosity) of fresh green bean particulates were investigated during drying. Three length:diameter ratios (1:1, 2:1 and 3:1) were considered, using drying conditions of 50 +/- 2 degrees C and 13 +/- 2% relative humidity in a heat pump dehumidifier system. The fluidization behaviour was also evaluated at 10 levels of moisture content. The fluidization experiments demonstrated that the minimum fluidization velocity decreases as the drying proceeds due to the reduced moisture content and changes in the physical properties of the bean particulates. Empirical relationships of the following nature were developed for the change in shrinkage [VR = 1 - Be-kMR], particle density [rho(p) = A + BMR + C (exp)(-D MR)], bulk density [rho(b) = a(1) + b(1)MR + c(1)MR(2)] and bed porosity [epsilon = a(2) + b(2)MR + c(2)MR(2)] with the moisture content during fluidized bed drying.
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We prospectively studied headache characteristics during 6 months after craniotomy performed for treatment of cerebral aneurysms in 79 patients. Semistructured interviews, headache diaries, the Hospital Anxiety and Depression Scale and the Epworth Sleepiness Scales, the Short Form-36 Health Survey (SF-36) and McGill Pain Questionnaire were used. Seventy-two patients had headaches, half before the fifth day after surgery. Changes were observed in headache diagnosis, side and site in the postoperative period. Headache frequency increased immediately after surgery and then decreased over time. Headache frequency was associated with depressive and anxiety symptoms. Pain intensity was higher in women and in patients with more anxiety symptoms. An incidence of post-craniotomy headache of 40% was observed according to International Headache Society classification criteria, 10.7% of the acute and 29.3% of the chronic type. The bodily pain domain of the SF-36 was worse in patients with more anxiety symptoms. Greater frequencies of headache were associated with lower scores on bodily pain and social functioning.
Resumo:
The surface oxidation of two polyimides containing fluorinated phenylphosphine oxide units, TOR-RC and TOR-RC ODPA, have been studied by (XPS) spectroscopy following gamma -radiolysis under vacuum or in air and subsequent treatment in a water plasma. The changes in the O 1s/C 1s ratios obtained from (XPS) analysis showed that on exposure to the water plasma the ratio increases and then levels to a constant value which is similar to that found for exposure to the plasma without prior gamma -radiation treatment. Evidence for the formation of phosphate species was also obtained from the (XPS) analyses. (C) 2001 Elsevier Science Ltd. All rights reserved.
Resumo:
Little is known of how client fish minimise the costs of cleaning behaviour while maximising ectoparasite removal by cleaner fish. Previous studies have found that abundance on fish and infestation behaviour of gnathiid isopods, the main parasite eaten by cleaner fish, varies diurnally. We examined whether reduced foraging is a cost of cleaning behaviour in clients and whether the behaviour of the client fish, the thick-lipped wrasse Hemigymnus melapterus, towards the cleaner fish Labroides dimidiatus varied diurnally to maximise ectoparasite removal, possibly in response to the diurnal changes in the abundance and infestation patterns of gnathiids. We found that during the midday and afternoon, client foraging rates were negatively related to the duration and frequency of inspections, suggesting that cleaning may, at some times of the day, be energetically costly to the client in terms of reduced foraging opportunities. Surprisingly, we found that the duration and frequency of inspections of clients by cleaners did not vary among diel time periods. A model of gnathiid dynamics on individual fish is proposed. It shows that the observed diurnal pattern in gnathiid abundance on fish can be generated with the constant duration and frequency of inspections that was observed in this study. Thus clients would not have more gnathiids removed by modifying their cleaning behaviour.
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Langmuir monolayer films of the tetracationic porphyrin tetrakis(octadecyl-4-pyridin ium)porphyrinatozinc(II) bromide on various salt containing subphases were analyzed using surface pressure-area isotherms and X-ray reflectivity. The use of these complementary techniques showed that the porphyrin molecules undergo changes in conformation upon compression. Two main phases were identified, one in which the porphyrin moiety is parallel to the subphase and one in which the porphyrin moiety is tilted out of the plane. The addition of different salts into the subphase brought about changes in film behaviour, which are explained in terms of a lyotropic series. Copyright (C) 2002 Society of Porphyrins,& Phthalocyanines.
Resumo:
The objective of this study was to investigate how seasonally fluctuating environmental conditions influence the diving performance of the highly aquatic, bimodally respiring turtle Rheodytes leukops in a natural setting. Over four consecutive seasons (Austral autumn 2000 to summer 2001), the diving behaviour of adult turtles was recorded via pressure-sensitive time-depth recorders within Marlborough Creek, central Queensland, Australia. Short surfacing intervals recorded for R. leukops in winter suggest that the species utilizes aquatic respiration as an overwintering strategy to prevent the development of a metabolic acidosis during the long inactive dives observed during the season. As water temperature increases and aquatic P-O 2 decreases, R. leukops switches from facultative to obligate air-breathing, presumably because of the increased metabolic cost associated with aquatic respiration under summer conditions. Increases in mean surfacing time from winter to spring and summer are attributed to seasonal changes in behaviour possibly associated with foraging rather than to the physiological state of the turtle, given that no difference in median surfacing time among seasons was observed.
Resumo:
Improving the treatment of obesity remains a critical challenge. Several health behaviour change models, often based on a social-cognitive framework, have been used to design weight management interventions (Baranowski et al., 2003). However, most interventions have only produced modest weight reductions (Wadden et al., 2002) and socialcognitive variables have shown limited power to predict weight outcomes (Palmeira et al., 2007). Other predictors, and possibl alte nati e e planatory models, are needed to better understand the mechanisms by which weight loss and other obesity treatment-outcomes are brought about (Baranowski, 2006). Self-esteem is one of these possible mechanisms, because is commonly reported to change during the treatment, although these changes are not necessarily associated with weight loss (Blaine et al., 2007; Maciejewski et al., 2005). This possibility should be more evident if the program integrates regular exercise, as it promotes improvements in subjective well-being (Biddle & Mutrie, 2001), with possible influences on long-term behavioral adherence (e.g. diet, exercise). Following the reciprocal effects model tenets (Marsh & Craven, 2006), we expect that the influences between changes in weight, selfesteem and exercise to be reciprocal and might present one of the mechanisms by which obesity treatments can be improved.