21 resultados para Inheritance of regularity


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Inheritance of three kinds of molecular genetic markers (mtDNA, random-amplified polymorphic DNAs (RAPDs) and allozymes) and sex were investigated in crossbreeding experiments between three populations of the Australian freshwater crayfish Cherax destructor. Crossbreeding did not disrupt the ively maternally inherited, and allozyme and RAPD markers were transmitted following expected Mendelian principles for co-dominant and dominant traits respectively. Unlike these three markers, sex ratios were found to be distorted by crossbreeding in some families. Two crossbred families produced only females. The implications of these findings for freshwater crayfish population genetics, taxonomy and aquaculture are discussed.


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This is the first study to present empirical data describing the social organisation and breeding biology of the White-browed Treecreeper (Climacteris affinis). The species is typical of many small Australian passerines in that it has high annual survival (~80%), small clutches (mean = 1.95 ± 0.05), long breeding seasons (eggs laid August to November) and long incubation (17–18 days) and nestling periods (25–26 days), corrected for body weight. Reproductive effort is modified in response to variation in climatic conditions by adjusting the commencement of breeding and number of clutches laid per season, which is facilitated by an extended breeding season. White-browed Treecreepers occupied relatively large (mean = 8.4 ± 0.8 ha), all-purpose territories throughout the year. However, unlike many group territorial birds, territory size was not related to the number of occupants. The role of food limitation and climatic variability in relation to territory dispersion and life-history traits is explored. Facultative cooperative breeding was confirmed. Cooperative groups were formed through male philopatry, with usually only one, but up to three, male helpers present in a moderate fraction (35%) of breeding units. Thus, all species of Climacteris are now confirmed as facultative cooperatively breeding species, which provides further evidence for the aggregation of cooperative breeders at the generic level in mixed (i.e. cooperative and pair breeders) phylogenetic clades. In C. affinis, males may attain breeding positions through inheritance of their natal territory or by filling vacancies in nearby territories. Females obtained breeding positions by ‘floating’ as non-breeding residents in established territories, waiting for a vacancy to arise.

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Since climate change captured global attention in the 1990s, the private individual, addressed as a member of a concerned public, has occupied a focal position in the discourse of environmental amelioration. Recently, a range of prominent books, films and television programs — for example, Tim Flannery’s The Weather Makers (2005), Al Gore’s An Inconvenient Truth (2006) and ABC TV’s Carbon Cops (2007) — have promoted the role of the individual as the ‘starting point’ for effective environmental action. These texts assume that the provision and comprehension of sufficient information to the public about climate change will change individual habits and practices. This accords with the ‘information-deficit model’ in environmental communication research, a concept that asserts a direct connection between individual awareness and response, and collective action. This paper discusses the limitations of this model, pervasive in both popular and official approaches to climate change. It will interrogate the philosophical assumptions that underlie it, in which nature and culture are polarised and the human is positioned in a certain, and separate, relationship to the non-human world — an inheritance of the very logic that enables the continued exploitation of nature. Applying Bruno Latour’s notion of a ‘matter of concern’ to climate change, where the gathering of a range of irreducible forces and im/materialities continually produce these phenomena, this paper proposes that, in thinking about climate change as essentially unrepresentable, a different mode of public engagement with the issue is asserted.

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Cardiovascular disease (CVD) is the leading cause of death worldwide and originates in early life. The exact mechanisms of this early-life origin are unclear, but a likely mediator at the molecular level is epigenetic dysregulation of gene expression. Epigenetic factors have thus been posited as the likely drivers of early-life programming of adult-onset diseases. This review summarizes recent advances in epidemiology and epigenetic research of CVD risk in children, with a particular focus on twin studies. Classic twin studies enable partitioning of phenotypic variance within a population into additive genetic, shared, and nonshared environmental variances, and are invaluable in research in this area. Longitudinal cohort twin studies, in particular, may provide important insights into the role of epigenetics in the pathogenesis of CVD. We describe candidate gene and epigenome-wide association studies (EWASs) and transgenerational epigenetic inheritance of CVD, and discuss the potential for evidence-based interventions. Identifying epigenetic changes associated with CVD-risk biomarkers in children will provide new opportunities to unravel the underlying biological mechanism of the origins of CVD and enable identification of those at risk for early-life interventions to alter the risk trajectory and potentially reduce CVD incidence later in life.

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In this paper, we consider a class of time-delay singular systems with Lipschitz non-linearities. A method of designing full-order observers for the systems is presented which can handle non-linearities with large-Lipschitz constants. The Lipschitz conditions are reformulated into linear parameter varying systems, then the Lyapunov–Krasovskii approach and the convexity principle are applied to study stability of the new systems. Furthermore, the observers design does not require the assumption of regularity for singular systems. In case the systems are non-singular, a reduced-order observers design is proposed instead. In both cases, synthesis conditions for the observers designs are derived in terms of linear matrix inequalities which can be solved efficiently by numerical methods. The efficiency of the obtained results is illustrated by two numerical examples.

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Normal skeletal muscle metabolism is essential for whole body metabolic homoeostasis and disruptions in muscle metabolism are associated with a number of chronic diseases. Transcriptional control of metabolic enzyme expression is a major regulatory mechanism for muscle metabolic processes. Substantial evidence is emerging that highlights the importance of epigenetic mechanisms in this process. This review will examine the importance of epigenetics in the regulation of muscle metabolism, with a particular emphasis on DNA methylation and histone acetylation as epigenetic control points. The emerging cross-talk between metabolism and epigenetics in the context of health and disease will also be examined. The concept of inheritance of skeletal muscle metabolic phenotypes will be discussed, in addition to emerging epigenetic therapies that could be used to alter muscle metabolism in chronic disease states.

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The Medical Board of Victoria (Board) was created in 1844 to register “legally qualified medical practitioners”. It was not until 1933, however, that the Board attained the power to remove from its register a doctor who had engaged in “infamous conduct in a professional respect” (the power), even though the General Council of Medical Education and Registration of the United Kingdom on which the Board was modelled had been granted the power 75 years earlier. This article argues that the delay in the Board’s inheritance was attributable to successive Victorian Parliaments’ distrust of the Board and that this attitude was unwarranted, at least from early in the 20th century. The article maintains that the granting of the power to the Board was a crucial event in the history of the regulation of the Victorian medical profession. This is illustrated both by the difficulty encountered by the medical profession in dealing with doctors’ unethical conduct before 1933, and the Board’s concern to use its new authority responsibly and appropriately to protect the public and the profession in the three years after it attained the power.

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A two-stage random telephone/mail survey was conducted during the last quarter of 1998 among Adelaide residents to determine consumers' use of soy bread and other soy products and their health expectations of soy products. One in five (21%) of 1477 telephone subscribers usually consumed soy bread and related soy products. Comparisons of soy bread consumers and non-consumers, based on the mail survey sample, showed that more soy bread consumers used dietary supplements and ate low fat and vegetarian diets, though their experiences of ill health were similar. Soy bread consumers held stronger universalism (pro-nature) values than non-consumers. They also held more positive expectations about the benefits of soy consumption, including reductions in menstrual and menopausal symptoms, increased bowel regularity and reductions in the risk of heart disease and cancer. The findings are discussed in relation to the psychology of dietary supplementation, values orientations and physiological plausibility. Further investigations are suggested.

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Two existing models are used to conceptualize the constrained and limited participation in the communist system. The mobilization model suggests that participation was so mobilized by the party/state that it was largely meaningless, while the disengagement model supports the idea that many communist citizens adopted non-participatory behaviors such as non-voting as a means of protest. This paper attempts to demonstrate the importance of a third model – the emergent democratic culture model. The survey results show that the participation index is in proportion to the number of elections in which a villager is involved; and a growing number of voters in Zhejiang are developing citizen-initiated participation, with rights consciousness.

This research finds that the level of participation is influenced by three major factors: the perceived worth of the election itself, regularity of electoral procedures, and the fairness of electoral procedures. It also finds that parochial political culture and political apathy still exist, and the emergent democratic consciousness falls short of an ideal democratic standard. While a highly democratic culture helps to develop village democracy, the apathetic attitude continues to support the authoritarian leadership and structure in many villages. The paper also gives an account of survey research in rural China and offers a thoughtful critique of the use of voting and non-voting as the sole indicator of political participation.

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This paper reports the three-stage development of a professional practice audit questionnaire for mental health nursing in Aotearoa/New Zealand. In Study 1, clinical indicator statements (n = 99) generated from focus group data, which were considered to be unobservable in the nursing documentation in consumer case notes, were included in a three-round Delphi process. Consensus of ratings occurred for the mental health nurse and academic participants (n = 7) on 83 clinical indicator statements. In Study 2, the clinical indicator statements (n = 67) that met importance and consensus criteria were incorporated into a questionnaire, which was piloted at a New Zealand mental health service. The questionnaire was then modified for use in a national field study. In Study 3, the national field study, registered mental health nurses (n = 422) from 11 New Zealand District Health Board mental health services completed the questionnaire. Five categories of nursing practice were identified: professional and evidence-based practice; consumer focus and reflective practice; professional development and integration; ethically and legally safe practice; and culturally safe practice. Analyses revealed little difference in the perceptions of nurses from different backgrounds regarding the regularity of the nursing practices. Further research is needed to calibrate the scores on each clinical indicator statement with behaviour in clinical practice.

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This paper describes the development and validation of bicultural clinical indicators that measure achievement of mental health nursing practice standards in New Zealand (ANZMCHN, 1995, Standards of practice for mental health nursing in New Zealand. ANZCMHN, Greenacres). A four-stage research design was utilised including focus groups, Delphi surveys, a pilot, and a national field study, with mental health nurses and consumers as participants. During the national field study, consumer files (n=327) from 11 District Health Boards, and registered nurses (n=422) completed an attitude questionnaire regarding the regularity of specific nursing and service activities. Results revealed a variation in the mean occurrence of the clinical indicators in consumer case notes of 18.5–89.9%. Five factors with good internal consistency, encompassing domains of mental health nursing required for best practice, were derived from analysis of the questionnaire. This study presents a research framework for developing culturally and clinically valid, reliable measures of clinical practice.

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This study examines the direct and indirect influence of various aspects of enjoyment, including activity enjoyment, enjoyment conceptualised as physical/environmental, and enjoyment conceptualised as social interaction, on regular participation in leisure-time physical activity (LTPA). The study was cross-sectional and used self-report questionnaires to collect data from a random sample of 250 people aged 19-87 years living in an Australian city. Questionnaires included demographic items and scales to measure enjoyment of LTPA, prioritisation of LTPA and regularity of participation in LTPA. The findings suggest that the influence of enjoyment on participation in LTPA is complex. Aspects of enjoyment have varying levels of influence on participation in LTPA and this influence is indirect through preference for LTPA, life priority of LTPA and making time for LTPA. Policies, programs and strategies by government and practitioners that aim to increase participation in LTPA should primarily aim to enhance activity enjoyment, rather than focusing on other aspects of participation. Theoretically, this study suggests that enjoyment is a multidimensional concept and that enjoyment is a part of a larger decision-making process influencing participation in LTPA.

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Various statistical methods have been proposed to evaluate associations between measured genetic variants and disease, including some using family designs. For breast cancer and rare variants, we applied a modified segregation analysis method that uses the population cancer incidence and population-based case families in which a mutation is known to be segregating. Here we extend the method to a common polymorphism, and use a regressive logistic approach to model familial aggregation by conditioning each individual on their mother's breast cancer history. We considered three models: 1) class A regressive logistic model; 2) age-of-onset regressive logistic model; and 3) proportional hazards familial model. Maximum likelihood estimates were calculated using the software MENDEL. We applied these methods to data from the Australian Breast Cancer Family Study on the CYP17 5UTR TC MspA1 polymorphism measured for 1,447 case probands, 787 controls, and 213 relatives of case probands found to have the CC genotype. Breast cancer data for first- and second-degree relatives of case probands were used. The three methods gave consistent estimates. The best-fitting model involved a recessive inheritance, with homozygotes being at an increased risk of 47% (95% CI, 28-68%). The cumulative risk of the disease up to age 70 years was estimated to be 10% or 22% for a CYP17 homozygote whose mother was unaffected or affected, respectively. This analytical approach is well-suited to the data that arise from population-based case-control-family studies, in which cases, controls and relatives are studied, and genotype is measured for some but not all subjects.