980 resultados para Daniels, Norm


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In some insects, the finding of oviposition substrate triggers the uptake into oocytes of yolk proteins that are stored in the fat body during post-embryonic development. The main host of the bean weevil Zabrotes subfasciatus (Coleoptera; Chrysomelidae; Bruchinae; Amblycerini), in which larval resources are the sole source for future egg maturation, is Phaseolus vulgaris. Despite not feeding as adults, females of this species are able to lay eggs after encountering host seeds but it is not known how females react to changes in the availability of bean seeds. In the present study, the behaviour of Z. subfasciatus facing two very different environments for oviposition is investigated, as well as how this influences offspring fitness. The results obtained show that females of Z. subfasciatus react to variations in the availability of seeds belonging to the same host species by adjusting egg size and number. Females on low bean seed density lay larger and fewer eggs than those on high bean seed density, demonstrating a trade-off between these reproductive traits. Moreover, females can adjust egg size to changing levels of host availability during the first 4 days of their oviposition period. Although no difference in offspring weight is found, those from small eggs (low competition environment) result in larger adults. No response to selection on these traits after rearing beetles on the same host for 40 generations is observed. This unresponsiveness may indicate that beetle populations behave according to their reaction norm that already allows rapid adaptation to a varying amount of host-seed availability and better exploitation of the environments of this widespread stored-seed pest.

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In the present research, a reconceptualisation of the role of norms in the link between prejudiced attitudes and discriminatory behaviour — along the lines suggested by the social identity perspective — was tested. In the first study, group salience and group norm were manipulated. As expected, participants ascribed negative traits to significantly fewer Asian university students when they had received consensus information along these lines from a salient ingroup rather than from a salient outgroup. These results were replicated on a measure of strength of motivation to appear nonprejudiced. In a second study, group salience and norm were once again manipulated and strength of attitude and perceived group threat were measured. As predicted, people's negative attitudes towards globalisation were more likely to predict congruent behavioural responses to the extent that the group norm supported the attitude and group salience was high, particularly when high levels of group threat were perceived.

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We discuss the existence of mild, classical and strict solutions for a class of abstract differential equations with nonlocal conditions. Our technical approach allows the study of partial differential equations with nonlocal conditions involving partial derivatives or nonlinear expressions of the solution. Some concrete applications to partial differential equations are considered. (C) 2010 Elsevier Ltd. All rights reserved.

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Objective: The aim of this study was to test the effectiveness of various attitude-behavior theories in explaining alcohol use among young adults. The theory of reasoned action (TRA), the theory of planned behavior and an extension of the TRA that incorporates past behavior were compared by the method of maximum-likelihood estimation, as implemented in LISREL for Windows 8.12. Method: Respondents consisted of 122 university students (82 female) who were questioned about their attitudes, subjective norms, perceived behavioral control, past behavior and intentions relating to drinking behavior. Students received course credit for their participation in the research. Results: Overall, the results suggest that the extension of the theory of reasoned action which incorporates past behavior provides the best fit to the data. For these young adults, their intentions to drink alcohol were predicted by their past behavior as well as their perceptions of what important others think they should do (subjective norm). Conclusions: The main conclusions drawn from the research concern the importance of focusing on normative influences and past behavior in explaining young adult alcohol use. Issues regarding the relative merit of various alternative models and the need for greater clarity in the measure of attitudes are also discussed.

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Aim: To trace a reference curve for motor development from birth up to 12 months of corrected chronological age in infants born preterm and low birth weight. Methods: This is a cross-sectional study with a sample of 308 preterm infants (53% boys) weighing < 2500 g at birth. The Alberta Infant Motor Scale (AIMS) was used for motor development assessment. Results: Comparing the motor performance of preterm infants with infants from a standardized sample on the AIMS, it was found that, except for the age group of the newborn, preterm infants showed lower motor development scores in comparison with the AIMS normative sample in all age groups between 1 and 12 months. The curve of motor development showed a continuous increase in the number of motor skills of preterm infants during their first 12 months of age. However, the average of motor acquisitions of preterm infants showed a nonlinear pattern with a standard indicator of stabilization between 8 and 10 months of age. Conclusion: Preterm infants, 1-12 months of age, showed motor development AIMS scores lower than the standards established in the normative sample. The findings may contribute as norm-reference for assessing the motor development of preterm infants in follow-up programmes in developing countries.

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Introduction The objective of this study was to analyse the accommodation needs of people with intellectual disability over the age of 18 years in Toowoomba and contiguous shires. In 2004, a group of carers established Toowoomba Intellectual Disability Support Association (TIDSA) to address the issue of the lack of supported accommodation for people with intellectual disability over the age of 18 and the concerns of ageing carers. The Centre for Rural and Remote Area Health (CRRAH) was engaged by TIDSA to ascertain this need and undertook a research project funded by the Queensland Gambling Community Benefit Fund. While data specifically relating to people with intellectual disability and their carers are difficult to obtain, the Australian Bureau of Statistics report that carers of people with a disability are more likely to be female and at least 65 years of age. Projections by the National Centre for Social and Economic Modelling (NATSEM) show that disability rates are increasing and carer rates are decreasing. Thus the problem of appropriate support to the increasing number of ageing carers and those who they care for will be a major challenge to policy makers and is an issue of immediate concern. In general, what was once the norm of accommodating people with intellectual disability in large institutions is now changing to accommodating into community-based residences (Annison, 2000; Young, Ashman, Sigafoos, & Grevell, 2001). However, in Toowoomba and contiguous shires, TIDSA have noted that the availability of suitable accommodation for people with intellectual disability over the age of 18 years is declining with no new options available in an environment of increasing demand. Most effort seemed to be directed towards crisis provision. Method This study employed two phases of data gathering, the first being the distribution of a questionnaire through local service providers and upon individual request to the carers of people with intellectual disability over the age of 18. The questionnaire comprised of Likert-type items intended to measure various aspects of current and future accommodation issues. Most questions were followed with space for free-response comments to provide the opportunity for carers to further clarify and expand on their responses. The second phase comprised semi-structured interviews conducted with ten carers and ten people with intellectual disability who had participated in the Phase One questionnaire. Interviews were transcribed verbatim and subjected to content analysis where major themes were explored. Results Age and gender Carer participants in this study totalled 150. The mean age of these carers was 61.5 years and ranged from 40 – 91 years. Females comprised 78% of the sample (mean age = 61.49; range from 40-91) and 22% were male (mean age = 61.7 range from 43-81). The mean age of people with intellectual disability in our study was 37.2 years ranging from 18 – 79 years with 40% female (mean age = 39.5; range from 19-79) and 60% male (mean age = 35.6; range from 18-59). The average age of carers caring for a person over the age of 18 who is living at home is 61 years. The average age of the carer who cares for a person who is living away from home is 62 years. The overall age range of both these groups of carers is between 40 and 81 years. The oldest group of carers (mean age = 70 years) were those where the person with intellectual disability lives away from home in a large residential facility. Almost one quarter of people with an intellectual disability who currently live at home is cared for by one primary carer and this is almost exclusively a parent.

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The anisotropic norm of a linear discrete-time-invariant system measures system output sensitivity to stationary Gaussian input disturbances of bounded mean anisotropy. Mean anisotropy characterizes the degree of predictability (or colouredness) and spatial non-roundness of the noise. The anisotropic norm falls between the H-2 and H-infinity norms and accommodates their loss of performance when the probability structure of input disturbances is not exactly known. This paper develops a method for numerical computation of the anisotropic norm which involves linked Riccati and Lyapunov equations and an associated special type equation.

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The flavivirus Japanese encephalitis (JE) virus has recently emerged in the Australasian region. To investigate the involvement of infections with related enzootic flaviviruses, namely Murray Valley encephalitis (MVE) virus and Kunjin (KUN) virus, on immunity of pigs to JE virus and to provide a basis for interpretation of serologic data, experimental infections were conducted with combinations of these viruses. Antibody responses to primary and secondary infections were evaluated using panels of monoclonal antibody-based blocking enzyme-link-ed immuno-sorbent assays and microtiter scrum neutralization tests (mSNTs). Identification of the primary infecting virus was possible only using the mSNTs. Following challenge, unequivocal diagnosis was impossible due to variation in immune responses between animals and broadened and/or anamnestic responses. Viremia for JE virus was readily detected in pigs following primary infection, but was not detected following prior exposure to MVE or KUN viruses. Boosted levels of existing cross-neutralizing antibodies to JE virus suggested a role for this response in suppressing JE viremia.

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This study describes the developmental changes in pulmonary surfactant (PS) lipids throughout incubation in the sea turtle, Chelonia mydas. Total phospholipid (PL), disaturated phospholipid (DSP) and cholesterol (Chol) harvested from lung washings increased with advancing incubation, where secretion was maximal at pipping, coincident with the onset of pulmonary ventilation. The DSP/PL ratio increased, whereas the Chol/PL and the Chol/DSP ratio declined throughout development. The phospholipids, therefore, are independently regulated from Chol and their development matches that of mammals. To explore whether hypoxia could elicit an effect on the development of the PS system, embryos were exposed to a chronic dose of 17% O-2 for the final similar to 40% of incubation. Hypoxia did not affect incubation time, absolute, nor relative abundance of the surfactant lipids, demonstrating that the development of the system is robust and that embryonic development continues unabated under mild hypoxia. Hypoxia-incubated hatchlings had lighter wet lung weights than those from normoxia, inferring that mild hypoxia facilitates lung clearance in this species. (C) 2001 Elsevier Science B.V. All rights reserved.

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The taxonomic relationship between two toothed South African river crabs, Potamonautes warreni and P. unispinus, is unclear. The problem stems from the widespread variation in carapace dentition patterns amongst P. warreni individuals over its biogeographic range, where single toothed individuals may appear similar in carapace morphology to P. unispinus. Ten populations of P. warreni and 18 populations of P. unispinus were collected and the morphometric and genetic differentiation between the two taxa quantified. Patterns of morphometric and genetic variation were examined using multivariate statistics and protein gel electrophoresis, respectively. Principal component analyses of carapace characters showed that the two species are morphologically indistinguishable. However, discriminate functions analyses and additional statistical results corroborate the morphological distinction between the two taxa. Allozyme electrophoresis of 17 protein coding loci, indicated a close genetic similarity between the two species (I = 0.92). A fixed allelic difference at one locus (LT-2) and extensive genetic variability at another locus (PGM-1) indicate that two gene pools are present and that the two taxa are genetically isolated. Intraspecific genetic I values for both species were > 0.97 and indicated no apparent genetic structuring on a micro or macro-geographic scale. The variation in carapace dentition among P. warreni populations possesses no genetic basis and may possibly toe the product of ecogenesis. The value of dentition patterns in the systematics of river crabs is discussed. Dentition patterns among river crab species appear to be conserved and reliable as species specific diagnostic markers, but should ideally be used in combination with other morphological data sets and genetic evidence.