994 resultados para 223
Resumo:
Online grocery shopping has enjoyed strong growth and it is predicted this channel will continue to grow exponentially in the coming years. While online shopping has attracted an abundance of research interest, examinations of online grocery shopping behaviour are only now emerging. Shopping online for groceries differs considerably from general online shopping due to the perishability and variability of the product, and frequency of the shopping activity. Two salient gaps underpin this research into online grocery shopping. This study responds to calls to investigate the online shoppers’ experience in the context of online purchasing frequency. Second, this study examines the mediating effect of perceived risk between trust and online repurchase intention of groceries. An online survey was employed to collect data from shoppers who were recruited from a multi-channel grocery e-retailer’s database. The online survey, comprising 16 reflective validated scale items, was sent to 555 frequent and infrequent online grocery shoppers. Results find that while customer satisfaction predicts trust for both infrequent and frequent online grocery shoppers, perceived risk fully mediates the effect of trust on repurchase intentions for infrequent online grocery shoppers. Furthermore path analysis reveals that the developed behavioural model is variant across both groups of shoppers. Theoretically, we provide a deeper understanding of the online customer experience, while gaining insight into two shopper segments identified as being important to grocery e-retailers. For managers, this study tests an online customer behavioural model with actual purchasing behaviour and identifies the continued presence of perceived risk in grocery e-retailing regardless of purchase frequency or experience.
Resumo:
Blue swimmer crabs (Portunus pelagicus) are an economically important crab caught in baited traps throughout the Indo-west Pacific and Mediterranean. In Australia they are traditionally caught using rigid wire traps (approximate to pots) but there has been a recent increase in the use of collapsible pots constructed from polyethylene trawl mesh. Two experiments were conducted in Moreton Bay, Queensland, to determine the ghost fishing potential of lost crab pots on both target and bycatch species and to evaluate the differences between traditional and contemporary pot designs. A lost contemporary, collapsible trawl mesh pot will catch between 3 and 223 R pelagicus per year after the bait has been exhausted, while a traditional wire mesh pot would catch 11-74 crabs peryear. As most fishers now use the collapsible trawl mesh pots, ghost fishing mortality could be as high as 111,811-670,866 crabs per year. Bycatch retention was also higher in contemporary designs. Periods of strong winds appeared to increase the ghost fishing potential of lost pots. The use of escape gaps, larger mesh sizes and construction options that allow for the deterioration of entrance funnels to minimise ghost fishing are recommended to reduce environmental impacts.
Resumo:
Coolamon is a mid-season to late-season flowering F4-derived crossbred subterranean clover of var. subterraneum, developed by the collaborating organisations of the National Annual Pasture Legume Improvement Program. It is a replacement for Junee and has been selected for release on the basis of its greater herbage production and persistence, and its resistance to both known races of clover scorch. Coolamon is recommended for sowing in Western Australia, New South Wales, Victoria, South Australia and Queensland. It is best suited to well-drained, moderately acidic soils in areas with a growing season of 6.5-8 months that extends into November. Coolamon is best suited to phase farming and permanent pasture systems. It can also be used in cropping rotations, but at least 2 years of pasture are required between crops. Coolamon has been granted Plant Breeders Rights in Australia.
Resumo:
A long two-layered circular cylinder having a thin orthotropic outer shell and a thick transversely isotropic core subjected to an axisymmetric radialv line load has been analysed. For analysis of the outer shell the classical thin shell theory was adopted and for analysis of the inner core the elasticity theory was used. The continuity of stresses and deformations at the interface has been satisfied by assumming perfect adhesion between the layers. Numerical results have been presented for two different ratios of outer shell thickness to inner radius and for three different ratios of modulus of elasticity in the radial direction of outer shell to inner core. The results have been compared with the elasticity solution of the same problem to bring out the reliability of this hybrid method. References
Resumo:
Multi-access techniques are widely used in computer networking and distributed multiprocessor systems. On-the-fly arbitration schemes permit one of the many contenders to access the medium without collisions. Serial arbitration is cost effective but is slow and hence unsuitable for high-speed multiprocessor environments supporting very high data transfer rates. A fully parallel arbitration scheme takes less time but is not practically realisable for large numbers of contenders. In this paper, a generalised parallel-serial scheme is proposed which significantly reduces the arbitration time and is practically realisable.
Resumo:
The effect of injection and suction on the generalised vortex flow of a steady laminar incompressible fluid over a stationary infinite disc with or without magnetic field under boundary-layer approximations has been studied. The coupled nonlinear ordinary differential equations governing the self-similar flow have been numerically solved using the finite-difference scheme. The results indicate that the injection produces a deeper inflow layer and de-stabilises the motion while suction or magnetic field suppresses the inflow layer and produces stability. The effect of decreasingn, the parameter characterising the nature of vortex flow, is similar to that of increasing the injection rate.
Resumo:
Is oral health becoming a part of the global health culture? Oral health seems to turn out to be part of the global health culture, according to the findings of a thesis-research, Institute of Dentistry, University of Helsinki. The thesis is entitled as “Preadolescents and Their Mothers as Oral Health-Promoting Actors: Non-biologic Determinants of Oral Health among Turkish and Finnish Preadolescents.” The research was supervised by Prof.Murtomaa and led by Dr.A.Basak Cinar. It was conducted as a cross-sectional study of 611 Turkish and 223 Finnish school preadolescents in Istanbul and Helsinki, from the fourth, fifth, and sixth grades, aged 10 to 12, based on self-administered and pre-tested health behavior questionnaires for them and their mothers as well as the youth’s oral health records. Clinically assessed dental status (DMFT) and self-reported oral health of Turkish preadolescents was significantly poorer than the Finns`. A similar association occurred for well-being measures (height and weight, self-esteem), but not for school performance. Turkish preadolescents were more dentally anxious and reported lower mean values of toothbrushing self-efficacy and dietary self-efficacy than did Finns. The Turks less frequently reported recommended oral health behaviors (twice daily or more toothbrushing, sweet consumption on 2 days or less/week, decreased between-meal sweet consumption) than did the Finns. Turkish mothers reported less frequently dental health as being above average and recommended oral health behaviors as well as regular dental visits. Their mean values for dental anxiety was higher and self-efficacy on implementation of twice-daily toothbrushing were lower than those of the Finnish. Despite these differences between the Turks and Finns, the associations found in common for all preadolescents, regardless of cultural differences and different oral health care systems, assessed for the first time in a holistic framework, were as follows: There seems to be interrelation between oral health and general-well being (body height-weight measures, school performance, and self-esteem) among preadolescents: • The body height was an explanatory factor for dental health, underlining the possible common life-course factors for dental health and general well-being. • Better school performance, high levels of self-esteem and self-efficacy were interrelated and they contributed to good oral health. • Good school performance was a common predictor for twice-daily toothbrushing. Self-efficacy and maternal modelling have significant role for maintenance and improvement of both oral- and general health- related behaviors. In addition, there is need for integration of self-efficacy based approaches to promote better oral health. • All preadolescents with high levels of self-efficacy were more likely to report more frequent twice-daily toothbrushing and less frequent sweet consumption. • All preadolescents were likely to imitate toothbrushing and sweet consumption behaviors of their mothers. • High levels of self-efficacy contributed to low dental anxiety in various patterns in both groups. As a conclusion: • Many health-detrimental behaviors arise from the school age years and are unlikely to change later. Schools have powerful influences on children’s development and well-being. Therefore, oral health promotion in schools should be integrated into general health promotion, school curricula, and other activities. • Health promotion messages should be reinforced in schools, enabling children and their families to develop lifelong sustainable positive health-related skills (self-esteem, self-efficacy) and behaviors. • Placing more emphasis on behavioral sciences, preventive approaches, and community-based education during undergraduate studies should encourage social responsibility and health-promoting roles among dentists. Attempts to increase general well-being and to reduce oral health inequalities among preadolescents will remain unsuccessful if the individual factors, as well as maternal and societal influences, are not considered by psycho-social holistic approaches.
Resumo:
OBJECTIVE To refine a previously reported linkage peak for endometriosis on chromosome 10q26, and conduct follow-up analyses and a fine-mapping association study across the region to identify new candidate genes for endometriosis. DESIGN Case-control study. SETTING Academic research. PATIENT(S) Cases=3,223 women with surgically confirmed endometriosis; controls=1,190 women without endometriosis and 7,060 population samples. INTERVENTION(S) Analysis of 11,984 single nucleotide polymorphisms on chromosome 10. MAIN OUTCOME MEASURE(S) Allele frequency differences between cases and controls. RESULT(S) Linkage analyses on families grouped by endometriosis symptoms (primarily subfertility) provided increased evidence for linkage (logarithm of odds score=3.62) near a previously reported linkage peak. Three independent association signals were found at 96.59 Mb (rs11592737), 105.63 Mb (rs1253130), and 124.25 Mb (rs2250804). Analyses including only samples from linkage families supported the association at all three regions. However, only rs11592737 in the cytochrome P450 subfamily C (CYP2C19) gene was replicated in an independent sample of 2,079 cases and 7,060 population controls. CONCLUSION(S) The role of the CYP2C19 gene in conferring risk for endometriosis warrants further investigation.
Resumo:
The interaction of the ionophore antibiotic lasalocid-A with lithium perchlorate in acetonitrile has been studied by circular dichroism (c.d.) and 1H, 13C and 7Li nuclear magnetic resonance (n.m.r.) techniques. Analysis of the c.d. data has shown that both the 2:1 sandwich (ionophore-cation-ionosphore) complex and 1:1 complex coexist in solution. The n.m.r. data are consistent with a conformational model in which the carbonyl oxygen, he tetrahydrofuran and the tetrahydropyran ring oxygen atoms, two hydroxyl group oxygens and either a water or a solvent molecule coordinate to the lithium ion.
Resumo:
OBJECTIVE: To further investigate a common variant (rs9939609) in the fat mass- and obesity-associated gene (FTO), which recent genome-wide association studies have shown to be associated with body mass index (BMI) and obesity. DESIGN: We examined the effect of this FTO variant on BMI in 3353 Australian adult male and female twins. RESULTS: The minor A allele of rs9939609 was associated with an increased BMI (P=0.0007). Each additional copy of the A allele was associated with a mean BMI increase of approximately 1.04 kg/m(2) (approximately 3.71 kg). Using variance components decomposition, we estimate that this single-nucleotide polymorphism accounts for approximately 3% of the genetic variance in BMI in our sample (approximately 2% of the total variance). By comparing intrapair variances of monozygotic twins of different genotypes we were able to perform a direct test of gene by environment (G x E) interaction in both sexes and gene by parity (G x P) interaction in women, but no evidence was found for either. CONCLUSIONS: In addition to supporting earlier findings that the rs9939609 variant in the FTO gene is associated with an increased BMI, our results indicate that the associated genetic effect does not interact with environment or parity.
Resumo:
Mikania micrantha or mile-a-minute is regarded as a major invasive weed in Papua New Guinea (PNG) and is now the target of a biological control program. As part of the program, distribution and physical and socioeconomic impacts of M. micrantha were studied to obtain baseline data and to assist with field release of biological control agents. Through public awareness campaigns and dedicated surveys, M. micrantha has been reported in all 15 lowland provinces. It is particularly widespread in East New Britain, as well as in West New Britain and New Ireland. A CLIMEX model suggests that M. micrantha has the potential to continue to spread throughout all lowland areas in PNG. The weed was found in a wide range of land uses, impacting on plantations and food gardens and smothering papaya, young cocoa, banana, taro, young oil palms, and ornamental plants. In socioeconomic surveys, M. micrantha was found to have severe impacts on crop production and income generated through reduced yields and high weeding costs, particularly in subsistence mixed cropping systems. About 89% of all respondents had M. micrantha on their land, and 71% of respondents had to weed monthly. Approximately 96% of respondents in subsistence mixed cropping systems used only physical means of control compared with 68% of respondents in other farming systems. About 45% of all respondents estimated that M. micrantha causes yield losses in excess of 30%. These studies suggest that there would be substantial benefits to landholders if biological control of M. micrantha were to be successful.
Resumo:
Northern peatlands are thought to store one third of all soil carbon (C). Besides the C sink function, peatlands are one of the largest natural sources of methane (CH4) to the atmosphere. Climate change may affect the C gas dynamics as well as the labile C pool. Because the peatland C sequestration and CH4 emissions are governed by high water levels, changes in hydrology are seen as the driving factor in peatland ecosystem change. This study aimed to quantify the carbon dioxide (CO2) and CH4 dynamics of a fen ecosystem at different spatial scales: plant community components scale, plant community scale and ecosystem scale, under hydrologically normal and water level drawdown conditions. C gas exchange was measured in two fens in southern Finland applying static chamber and eddy covariance techniques. During hydrologically normal conditions, the ecosystem was a CO2 sink and CH4 source to the atmosphere. Sphagnum mosses and sedges were the most important contributors to the community photosynthesis. The presence of sedges had a major positive impact on CH4 emissions while dwarf shrubs had a slightly attenuating impact. C fluxes varied considerably between the plant communities. Therefore, their proportions determined the ecosystem scale fluxes. An experimental water level drawdown markedly reduced the photosynthesis and respiration of sedges and Sphagnum mosses and benefited shrubs. Consequently, changes were smaller at the ecosystem scale than at the plant group scale. The decrease in photosynthesis and the increase in respiration, mostly peat respiration, made the fen a smaller CO2 sink. CH4 fluxes were significantly lowered, close to zero. The impact of natural droughts was similar to, although more modest than, the impact of the experimental water level drawdown. The results are applicable to the short term impacts of the water level drawdown and to climatic conditions in which droughts become more frequent.
Resumo:
Objectives: We sought to characterise the demographics, length of admission, final diagnoses, long-term outcome and costs associated with the population who presented to an Australian emergency department (ED) with symptoms of possible acute coronary syndrome (ACS). Design, setting and participants: Prospectively collected data on ED patients presenting with suspected ACS between November 2008 and February 2011 was used, including data on presentation and at 30 days after presentation. Information on patient disposition, length of stay and costs incurred was extracted from hospital administration records. Main outcome measures: Primary outcomes were mean and median cost and length of hospital stay. Secondary outcomes were diagnosis of ACS, other cardiovascular conditions or non-cardiovascular conditions within 30 days of presentation. Results: An ACS was diagnosed in 103 (11.1%) of the 926 patients recruited. 193 patients (20.8%) were diagnosed with other cardiovascular-related conditions and 622 patients (67.2%) had non-cardiac-related chest pain. ACS events occurred in 0 and 11 (1.9%) of the low-risk and intermediate-risk groups, respectively. Ninety-two (28.0%) of the 329 high-risk patients had an ACS event. Patients with a proven ACS, high-grade atrioventricular block, pulmonary embolism and other respiratory conditions had the longest length of stay. The mean cost was highest in the ACS group ($13 509; 95% CI, $11 794–$15 223) followed by other cardiovascular conditions ($7283; 95% CI, $6152–$8415) and non-cardiovascular conditions ($3331; 95% CI, $2976–$3685). Conclusions: Most ED patients with symptoms of possible ACS do not have a cardiac cause for their presentation. The current guideline-based process of assessment is lengthy, costly and consumes significant resources. Investigation of strategies to shorten this process or reduce the need for objective cardiac testing in patients at intermediate risk according to the National Heart Foundation and Cardiac Society of Australia and New Zealand guideline is required.
Resumo:
Background Sedentary behaviour is associated with several deleterious health consequences. Although device-based measures of sedentary time are available, they are costly and do not provide a measure of domain specific sedentary time. High quality self-report measures are necessary to accurately capture domain specific sedentary time, and to provide an alternative to devices when cost is an issue. In this study, the Past-day Adults’ Sedentary Time (PAST) questionnaire, previously shown to have acceptable validity and reliability in a sample of breast cancer survivors, was modified for a university sample and validity of the modified questionnaire was examined compared with activPAL. Methods Participants (n = 58, age = 18–55 years, 48% female, 66% students) were recruited from the University of Queensland (students and staff). They answered the PAST questionnaire, which asked about time spent sitting or lying down for work, study, travel, television viewing, leisure-time computer use, reading, eating, socialising and other purposes, during the previous day. Time reported for these questions was summed to provide a measure of total sedentary time. Participants also wore an activPAL device for the full day prior to completing the questionnaire and recorded their wake and sleep times in an activity log. Total waking sedentary time derived from the activPAL was used as the criterion measure. Correlation (Pearson's r) and agreement (Bland–Altman plots) between PAST and activPAL sedentary time were examined. Results Participants were sedentary (activPAL-determined) for approximately 66% of waking hours. The correlation between PAST and activPAL sedentary time for the whole sample was r = 0.50 [95% confidence interval (CI) = 0.28–0.67]; and higher for non-students (r = 0.63, 95% CI = 0.26–0.84) than students (r = 0.46, 95% CI = 0.16–0.68). Bland–Altman plots revealed that the mean difference between the two measures was 19 min although limits of agreement were wide (95% limits of agreement −4.1 to 4.7 h). Discussion The PAST questionnaire provides an acceptable measure of sedentary time in this population, which included students and adults with high workplace sitting. These findings support earlier research that questionnaires employing past-day recall of sedentary time provide a viable alternative to existing sedentary behaviour questionnaires.