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Hierarchical Nature (hierarchical + nature)
Selected AbstractsAdvantages of mixed effects models over traditional ANOVA models in developmental studies: A worked example in a mouse model of fetal alcohol syndromeDEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2007Patricia E. Wainwright Abstract Developmental studies in animals often violate the assumption of statistical independence of observations due to the hierarchical nature of the data (i.e., pups cluster by litter, correlation of individual observations over time). Mixed effect modeling (MEM) provides a robust analytical approach for addressing problems associated with hierarchical data. This article compares the application of MEM to traditional ANOVA models within the context of a developmental study of prenatal ethanol exposure in mice. The results of the MEM analyses supported the ANOVA results in showing that a large proportion of the variability in both behavioral score and brain weight could be explained by ethanol. The MEM also identified that there were significant interactions between ethanol and litter size in relation to behavioral scores and brain weight. In addition, the longitudinal modeling approach using linear MEM allowed us to model for flexible weight gain over time, as well as to provide precise estimates of these effects, which would be difficult in repeated measures ANOVA. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 664,674, 2007. [source] Genetic population structure of the net-winged midge, Elporia barnardi (Diptera: Blephariceridae) in streams of the south-western Cape, South Africa: implications for dispersalFRESHWATER BIOLOGY, Issue 1 2003M. J. Wishart SUMMARY 1.,The net-winged midges (Diptera: Blephariceridae), with highly specific habitat requirements and specialised morphological adaptations, exhibit high habitat fidelity and a limited potential for dispersal. Given the longitudinal and hierarchical nature of lotic systems, along with the geological structure of catchment units, we hypothesise that populations of net-winged midge should exhibit a high degree of population sub-structuring. 2.,Sequence variation in the cytochrome c oxidase subunit I (COI) region of the mitochondrial DNA (mtDNA) was examined to determine patterns of genetic variation and infer historical and contemporary processes important in the genetic structuring of populations of Elporia barnardi. The DNA variation was examined at sites within streams, between streams in the same range, and between mountain ranges in the south-western Cape of South Africa. 3.,Twenty-five haplotypes, 641 bp in length, were identified from the 93 individuals sampled. A neighbour-joining tree revealed two highly divergent clades (,5%) corresponding to populations from the two mountain ranges. A number of monophyletic groups were identified within each clade, associated with individual catchment units. 4.,The distribution of genetic variation was examined using analysis of molecular variance (amova). This showed most of the variation to be distributed among the two ranges (,80%), with a small percentage (,15%) distributed among streams within each range. Similarly, variation among streams on Table Mountain was primarily distributed among catchment units (86%). A Mantel's test revealed a significant relationship between genetic differentiation and geographical distance, suggesting isolation by distance (P < 0.001). 5.,Levels of sequence divergence between the two major clades, representing the two mountain ranges, are comparable with those of some intra-generic species comparisons. Vicariant events, such as the isolation of the Peninsula mountain chain and Table Mountain, may have been important in the evolution of what is now a highly endemic fauna. 6.,The monophyletic nature of the catchment units suggests that dispersal is confined to the stream environment and that mountain ridges provide effective physical barriers to dispersal of E. barnardi. [source] Doing Gender in Academic Education: The Paradox of VisibilityGENDER, WORK & ORGANISATION, Issue 4 2009Marieke Van Den Brink Recent contributions in the field of gender and organization point to the notion of paradox to unveil the persistence of gender inequality in organizations. This article seeks to contribute to this growing body of knowledge. We used the notion of paradox to reveal the processes of doing gender at an earth science department of a Dutch university in order to find out whether gender segregation in academic and professional careers has already started during academic education. We focused on the study choices of female students in earth sciences and discovered the paradox of visibility, which enabled us to show the contradictory and ambiguous nature of how gender is done at this department. In this article we discuss the relationship between doing gender and paradox on a theoretical as well as an empirical level. We argue that paradoxes could be very useful when analysing doing gender in organizations, because paradoxes focus on the social process in which individual agency and social structures come together. We even suggest that paradoxes might help us to disrupt the hierarchical nature of the gender binary, because they allow for a constant reflection on ambiguity and contradictions in theorizing as well as in practice. [source] Spatial abundance structures in an assemblage of gall-forming sawfliesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2004M. A. McGeoch Summary 1Examination of the fine-scale internal structure of species geographical ranges, and interspecific variation therein across landscapes, contributes to a more comprehensive understanding of the structure of geographical ranges. Two components of this internal structure that require further examination are the occurrence, extent and position of spatial autocorrelation, and relationships between the spatial abundance structures of closely related, ecologically similar species. 2Here we compare the abundance structures of an assemblage of gall-forming sawflies (Tenthredinidae) across a landscape. We identify the relative roles of spatial and non-spatial factors in explaining their abundance structures and test the hypothesis that sawfly density is explained by host plant quality, as has been demonstrated repeatedly at finer scales. We use these results to distinguish between alternative sets of mechanisms that may be operating at the landscape scale. 3Species densities were mainly multimodal across the landscape and significantly spatially structured, with patch, periodic and trend components. The abundance structures thus mimic those found generally for species across the full extent of their geographical ranges. 4Many abundance structure characteristics were unique to species, with differences in their correlogram profiles, distances over which densities were positively autocorrelated, and the absence of significant spatial structure in one species. 5In contrast to previous, fine-scale studies, host plant quality explained little of the variation in sawfly gall density across the landscape, whereas unexplained spatial structure contributed between 30% and 50%. Based on knowledge of the biology of these species and the absence of competitive interactions, species dispersal characteristics and the Moran effect are suggested as probable alternative hypotheses at this scale. 6Therefore, a spatial approach has identified the hierarchical nature of mechanisms underlying the population dynamics of this sawfly assemblage for the first time. Furthermore, it has highlighted the importance of spatial processes in explaining the densities of species at the landscape scale, as well as the individualistic nature of their abundance structures. [source] Mapping space for water: screening for urban flash floodingJOURNAL OF FLOOD RISK MANAGEMENT, Issue 1 2008B. Hankin Abstract This paper builds on the ,Flooding from Other Sources' project (HA4a), funded as part of Defra's Making Space for Water strategy. The HA4a study concluded that flood risk mapping is feasible for many of the sources of flooding that were investigated, which are not currently covered by the Environment Agency Flood Map, using existing flow modelling and GIS tools. However, there are some major constraints in terms of the need to undertake extensive data collection to allow the generation of useful flood maps that are not dominated by modelling uncertainties. The project anticipated that different levels of data collection and modelling might be needed for different purposes, given the hierarchical nature of UK flood risk assessment and management in the United Kingdom under PPS25 and the EC Floods Directive. This paper compares and contrasts three different approaches to urban flood modelling using topographic analysis, blanket extreme rainfall and semi-coupled sewer/overland routing. The UK summer floods 2007 have highlighted the pressing need for mapping the risk from urban flash flooding, and the Pitt Review has recommended that areas at high risk from surface waters should be urgently identified. This can be done now at some level of detail, and we can be guided as to what level, from our increasing knowledge of vulnerable populations, from records of historical flooding and by using some of the screening methods described herein. [source] Parental mental illness: a review of barriers and issues for working with families and childrenJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 9 2009D. MAYBERY phd Accessible summary For the psychiatric workforce to become family focused (particularly in relation to children) there is a clear need for family sensitive policies and procedures, managerial and organizational support and well-targeted and sustained workforce training. However, there are multiple barriers to the adult mental health workforce becoming family focused including: ,,Some adult mental health services do not identify consumers who are parents and subsequently do not respond to children, parenting and family needs. ,,Organizations often do not have adequate family and child friendly policies and procedures. ,,The adult mental health workforce lacks skills and knowledge about families, children and parenting. ,,The workforce needs to increase encouragement of consumers to include family members and dependent children in treatment of the ill parent including the provision of psycho-education. Abstract Many consumers of psychiatric services are parents, making these services the opportunistic point for supporting consumers' children. While evidence suggests that assisting such children improves their mental health, there is a large gulf between what psychiatric services should (or could) provide and what they do in practice. This paper summarizes the constraining barriers and issues for the psychiatric workforce according to: (1) policy and management; (2) interagency collaboration; (3) worker attitude, skill and knowledge; (4) the parent-consumer; and (5) the consumer's family, including children. Potential solutions are presented, with a particular focus on the hierarchical nature of these barriers. Recommendations are made, including organizational audits to identify the most pressing barriers that impede family sensitive practice. [source] Implementation of the Zuluaga-Raysmith (Z-R) Model for Assessment of Perceived Basic Human Needs in Home Health Clients and CaregiversPUBLIC HEALTH NURSING, Issue 5 2000Beatrice Harrison Zuluaga R.N., FRCNA The Zuluaga-Raysmith (Z-R) model is a conceptual framework that incorporates accepted concepts of universal basic human needs developed by Maslow, yet removes the hierarchical nature of these. The Z-R model recognizes the existence of a health-illness continuum and accepts that an entity (individual, family, aggregate, or community) may move freely in the direction of greater health and self-actualization or towards illness and premature death. The Z-R model identifies 10 basic needs and recognizes that a perceived deficit in any one of these needs can adversely affect the level of wellness of the entity being considered. This exploratory and descriptive study used 11 nurses as interviewers. Subjects consisted of a convenience sample of homebound clients of a home health agency in a metropolitan city, and selected caregivers (n= 27). A modified functional wellness inventory (developed in 1993 by Louvenia Carter) was used with several open-ended questions, which together related to the 10 needs of the Z-R model. Reliability coefficient of the instrument was 0.84. Descriptive statistics were used to analyze the data, using means, percentages, and frequencies. Open-ended questions were grouped according to content and ranked in order of frequency. The five most pressing needs of this small sample were income; physical health; opportunity to make a contribution; mobility; and mental, emotional, social, and spiritual health (MESSH). Nurses unanimously reported that use of the instrument and the Z-R model helped them to focus on the total person, identify strengths in their clients, identify perceived needs deficits, and therefore, with the client, facilitate the preparation of a timely and cost-effective interdisciplinary plan of care to help the entity to move to a higher level of wellness despite the presence of chronic disease, disability, or impending death. These findings suggested that further research is warranted to explore the use of the Z-R model. A replication study is in progress. [source] Isn't the hierarchical nature of policy governance out of step with modern participative organizational styles?BOARD LEADERSHIP: POLICY GOVERNANCE IN ACTION, Issue 60 2002Article first published online: 15 MAR 200 No abstract is available for this article. [source] | ||||||||||||||||