Useful Framework (useful + framework)

Distribution by Scientific Domains

Selected Abstracts

Understanding sexual offending in schizophrenia

Christopher R. Drake M Clin Psych MAPS
Background Studies have found an elevated incidence of violent sexual offences in males with schizophrenia. The relationship between sexual offending and psychiatric illness is, however, complex and poorly defined. Aims The aim of the present article is to delineate possible mechanisms that underlie offensive sexual behaviour in schizophrenia that can be used as a framework for assessing and treating these behaviours. A review of research pertaining to the aetiology of sexual deviance in schizophrenia was conducted, focusing in particular on the role of early childhood experiences, deviant sexual preferences, antisocial personality traits, psychiatric symptomatology and associated treatment effects, the impact of mental illness on sexual and social functioning, and other potential contributory factors. Towards a typology It is proposed that schizophrenic patients who engage in sexually offensive activities fall into four broad groups: (1) those with a pre-existing paraphilia; (2) those whose deviant sexuality arises in the context of illness and/or its treatment; (3) those whose deviant sexuality is one manifestation of more generalized antisocial behaviour, and (4) factors other than the above. This classification provides a useful framework for evaluating and treating sexually offensive behaviours in schizophrenic patients. Copyright © 2004 Whurr Publishers Ltd. [source]

Capturing Flow in the Business Classroom

Yi Maggie Guo
ABSTRACT This study focuses on the flow experience in business education. Flow experience, characterized by concentration, control, and enjoyment, can lead to better learning outcomes. Leading preconditions of flow include the balance of challenge and skill, feedback, and goal clarity. Other situational factors affect the flow experience through the mediating effects of these three factors. In this article, we extend an existing framework linking flow and learning. Using the model as a guide, we start our research effort of flow in business education by conducting a field survey of student learning experience in terms of flow and influential factors. Data were collected using business students taking an introductory Operations Management course. The analysis reveals that flow does exist in classroom learning. Its key dimensions are concentration, sense of control, and enjoyment. The more important leading factor is having clear feedback. Characteristics of both the instructor and students play a role in the flow experience of students during lecture. It is evident that flow theory offers a useful framework for business education research. Suggestions for future research are made. [source]

Modelling species distributions in Britain: a hierarchical integration of climate and land-cover data

ECOGRAPHY, Issue 3 2004
Richard G. Pearson
A modelling framework for studying the combined effects of climate and land-cover changes on the distribution of species is presented. The model integrates land-cover data into a correlative bioclimatic model in a scale-dependent hierarchical manner, whereby Artificial Neural Networks are used to characterise species' climatic requirements at the European scale and land-cover requirements at the British scale. The model has been tested against an alternative non-hierarchical approach and has been applied to four plant species in Britain: Rhynchospora alba, Erica tetralix, Salix herbacea and Geranium sylvaticum. Predictive performance has been evaluated using Cohen's Kappa statistic and the area under the Receiver Operating Characteristic curve, and a novel approach to identifying thresholds of occurrence which utilises three levels of confidence has been applied. Results demonstrate reasonable to good predictive performance for each species, with the main patterns of distribution simulated at both 10 km and 1 km resolutions. The incorporation of land-cover data was found to significantly improve purely climate-driven predictions for R. alba and E. tetralix, enabling regions with suitable climate but unsuitable land-cover to be identified. The study thus provides an insight into the roles of climate and land-cover as determinants of species' distributions and it is demonstrated that the modelling approach presented can provide a useful framework for making predictions of distributions under scenarios of changing climate and land-cover type. The paper confirms the potential utility of multi-scale approaches for understanding environmental limitations to species' distributions, and demonstrates that the search for environmental correlates with species' distributions must be addressed at an appropriate spatial scale. Our study contributes to the mounting evidence that hierarchical schemes are characteristic of ecological systems. [source]

Introduced species as evolutionary traps

Martin A. Schlaepfer
Abstract Invasive species can alter environments in such a way that normal behavioural decision-making rules of native species are no longer adaptive. The evolutionary trap concept provides a useful framework for predicting and managing the impact of harmful invasive species. We discuss how native species can respond to changes in their selective regime via evolution or learning. We also propose novel management strategies to promote the long-term co-existence of native and introduced species in cases where the eradication of the latter is either economically or biologically unrealistic. [source]

Women and Work in the Information Age

Celia Stanworth
Widespread social transformation and new class structures are predicted with the coming of the ,information age', but there is disagreement about the likely outcomes for work and em-ployment patterns. Mainstream writing on the information age, both from the functionalist and Marxist traditions, tends not to consider likely consequences for women, but recent feminist research on gender and technology, treating technology as masculine culture, offers a useful framework for further research. This article argues that the information age may lead to some areas of convergence between the sexes in their experience of future work, but men may continue to defend areas of competence and to dominate the high status and powerful occupational positions of the future. [source]

Communicating the psychological contract: an employer perspective

David E. Guest
The concept of the psychological contract, with its focus on the exchange of perceived promises and commitments, is increasingly used as a framework to study the employment relationship. Yet research has predominantly focused on employee views and has largely neglected the organisational perspective and the management of the psychological contract. This article begins to redress the balance by reporting a study, based on a survey of 1,306 senior HR managers, that explores the management of the psychological contract and in particular the role of organisational communication. Three distinct and relevant aspects of organisational communication are identified, concerned with initial entry, day-to-day work and more future-oriented, top-down communication. Effective use of these forms of communication is associated with what managers judge to be a clearer and less frequently breached set of organisational promises and commitments, as well as with a fairer exchange and a more positive impact of policies and practices on employee attitudes and behaviour. The findings are discussed within the context of the wider literature on psychological contracts, organisational culture and HRM. The study confirms that the psychological contract offers managers a useful framework within which to consider and manage the employment relationship. [source]

The integration of thermal infrared imaging, discharge measurements and numerical simulation to quantify the relative contributions of freshwater inflows to small estuaries in Atlantic Canada

Serban Danielescu
Abstract Nutrient fluxes from developed catchments are often a significant factor in the declining water quality and ecological functioning in estuaries. Determining the relative contributions of surface water and groundwater discharge to nutrient-sensitive estuaries is required because these two pathways may be characterized by different nutrient concentrations and temporal variability, and may thus require different remedial actions. Quantifying the volumetric discharge of groundwater, which may occur via diffuse seepage or springs, remains a significant challenge. In this contribution, the total discharge of freshwater, including groundwater, to two small nutrient-sensitive estuaries in Prince Edward Island (Canada) is assessed using a unique combination of airborne thermal infrared imaging, direct discharge measurements in streams and shoreline springs, and numerical simulation of groundwater flow. The results of the thermal infrared surveys indicate that groundwater discharge occurs at discrete locations (springs) along the shoreline of both estuaries, which can be attributed to the fractured sandstone bedrock aquifer. The discharge measured at a sub-set of the springs correlates well with the area of the thermal signal attributed to each discharge location and this information was used to determine the total spring discharge to each estuary. Stream discharge is shown to be the largest volumetric contribution of freshwater to both estuaries (83% for Trout River estuary and 78% for McIntyre Creek estuary); however, groundwater discharge is significant at between 13% and 18% of the total discharge. Comparison of the results from catchment-scale groundwater flow models and the analysis of spring discharge suggest that diffuse seepage to both estuaries comprises only about 25% of the total groundwater discharge. The methods employed in this research provide a useful framework for determining the relative volumetric contributions of surface water and groundwater to small estuaries and the findings are expected to be relevant to other fractured sandstone coastal catchments in Atlantic Canada. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Towards a distinctive body of knowledge for Information Systems experts: coding ISD process knowledge in two IS journals

Juhani Iivari
Abstract., This paper introduces the idea of coding a practically relevant body of knowledge (BoK) in Information Systems (IS) that could have major benefits for the field. In its main part, the paper focuses on the question if and how an underlying body of action-oriented knowledge for IS experts could be distilled from the IS research literature. For this purpose the paper identifies five knowledge areas as the most important parts for an IS expert's BoK. Two of these are claimed as distinct areas of competence for IS experts: IS application knowledge and IS development (ISD) process knowledge. The paper focuses particularly on ISD process knowledge because it allows the organizing of practically relevant IS knowledge in an action-oriented way. The paper presents some evidence for the claim that a considerable body of practically relevant IS process knowledge might, indeed, exist, but also notes that it is highly dispersed in the IS literature. It then argues that the IS research community should take stock of this knowledge and organize it in an action-oriented way. Based on results from prior work it proposes a four-level hierarchical coding scheme for this purpose. In order to test the idea of coding action-oriented knowledge for IS experts, the paper reports the results of a coded literature analysis of ISD research articles published from 1996 to 2000 in two leading IS journals , Information Systems Journal and MIS Quarterly. The results suggest that ISD approaches form a useful framework for organizing practically relevant IS knowledge. [source]

FETI-DP, BDDC, and block Cholesky methods

Jing Li
Abstract The FETI-DP and BDDC algorithms are reformulated using Block Cholesky factorizations, an approach which can provide a useful framework for the design of domain decomposition algorithms for solving symmetric positive definite linear system of equations. Instead of introducing Lagrange multipliers to enforce the coarse level, primal continuity constraints in these algorithms, a change of variables is used such that each primal constraint corresponds to an explicit degree of freedom. With the new formulation of these algorithms, a simplified proof is provided that the spectra of a pair of FETI-DP and BDDC algorithms, with the same set of primal constraints, are essentially the same. Numerical experiments for a two-dimensional Laplace's equation also confirm this result. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Currency crisis duration and interest defence

Tullio Gregori
Abstract Asymmetric wars of attrition between speculators and a Central Bank can provide a useful framework to address currency crisis length and explain why a speculative attack can fail after some time. Interest rate defence can be analysed too. A non-linear relationship between interest rates and peg defence emerges, as a rate upsurge can reduce both concession times. With some welfare loss functions, increasing the domestic rate too much is a self-defeating policy as the Central Bank will opt out before speculators concede, but the reverse holds for lower rates. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Dempster,Shafer belief structures with interval valued focal weights

Ronald R. Yager
Dempster,Shafer belief structures provide a useful framework for the representation of information about a variable whose value is uncertain. Important parameters in these structures are the weights associated with the focal elements. These weights, which can be viewed as probabilities, are required to be precisely known. Here we relax this requirement and we consider the situation in which our knowledge of the weights associated with the focal elements is that they lie in some known interval rather then being precisely specified. This relaxation will allow us to more realistically model situations in which the weights cannot be precisely obtained. At a formal level, this situation can be viewed as one in which we have some uncertainty as to what is the actual belief structure, this uncertainty being of the possibilistic type. We introduce the measures of plausibility and belief in this environment. We also look at the issue of combining belief structures for these interval type belief structures. © 2001 John Wiley & Sons, Inc. [source]

The Ottawa Charter,from nursing theory to practice: Insights from the area of alcohol and other drugs

Morgan Smith RN
This article aims to assist nursing services to use the Ottawa Charter as a framework for nursing practice. Incorporation of the Ottawa Charter for Health Promotion into a nursing structure constitutes an innovation in nursing practice that was evaluated as a quality improvement exercise in a health-care organization responsible for providing services in the area of alcohol and other drugs. The evaluation consisted of two stages and sought to identify the degree to which the framework was effective in practice. This involved identifying issues surrounding the implementation of the Ottawa Charter as a framework for nursing practice as well as identifying the means by which quality improvements could occur. The evaluation involved an initial questionnaire to all nursing staff, followed by a series of focus groups. The data collected was both informative and enlightening and revealed a range of pertinent issues such as staff understanding and interpretation of the Ottawa Charter, expansion of the nurse's role and suggestions for organizational change. The Ottawa Charter strategies are discussed in relation to their relevance to the organization under evaluation and also expanded into recommendations to assist those contemplating using the Ottawa Charter as a framework for nursing practice. There was considerable agreement among the respondents that the Ottawa Charter provided a useful framework for nursing practice, but was on occasions problematic. [source]

Social Group and Moral Orientation Factors as Mediators of Religiosity and Multiple Attitude Targets

Although there is a tradition of examining generalized discrimination against multiple targets, recent studies have tended to consider race and homosexuality as separate targets without considering their relationship with each other. Recent studies have also argued for a moral dimension in attitudes to homosexuality, but this has not yet been explicitly modeled as an explanation for patterns of social attitudes. In a questionnaire study of practicing Australian Christians (N= 143), we examined the relationship of religious orientation and ideology (intrinsic, extrinsic, fundamentalism, orthodoxy, and quest) with four attitude targets (Aboriginal Australians, women, homosexual persons, and abortion). Using structural equation modeling (SEM), we develop a two-factor model, incorporating group and moral orientation factors, which completely mediates the relationships between the religiosity variables and the social attitudes. Religiosity variables exhibit different patterns of correlation with the two factors. The two-factor model provides a useful framework for further exploration of socially and politically contested attitudes. [source]

Resources, Staff Beliefs and Organizational Culture: Factors in the Use of Information and Communication Technology for Adults with Intellectual Disabilities

Sarah Parsons
Background, Access to, and the use of, information and communication technology (ICT) is increasingly becoming a vital component of mainstream life. First-order (e.g. time and money) and second-order factors (e.g. beliefs of staff members) affect the use of ICT in different contexts. It is timely to investigate what these factors may be in the context of service provision for adults with intellectual disabilities given the role ICT could play in facilitating communication and access to information and opportunities as suggested in Valuing People. Method, Taking a qualitative approach, nine day service sites within one organization were visited over a period of 6 months to observe ICT-related practice and seek the views of staff members working with adults with intellectual disabilities. All day services were equipped with modern ICT equipment including computers, digital cameras, Internet connections and related peripherals. Results, Staff members reported time, training and budget as significant first-order factors. Organizational culture and beliefs about the suitability of technology for older or less able service users were the striking second-order factors mentioned. Despite similar levels of equipment, support and training, ICT use had developed in very different ways across sites. Conclusion, The provision of ICT equipment and training is not sufficient to ensure their use; the beliefs of staff members and organizational culture of sites play a substantial role in how ICT is used with and by service users. Activity theory provides a useful framework for considering how first- and second-order factors are related. Staff members need to be given clear information about the broader purpose of activities in day services, especially in relation to the lifelong learning agenda, in order to see the relevance and usefulness of ICT resources for all service users. [source]

An integrative review and meta-synthesis of the scope and impact of intensive care liaison and outreach services

Ruth Endacott
Aim., To determine activities and outcomes of intensive care unit Liaison Nurse/Outreach services. The review comprised two stages: (1) integrative review of qualitative and quantitative studies examining intensive care liaison/outreach services in the UK and Australia and (2) meta-synthesis using the Nursing Role Effectiveness Model as an a priori model. Background., Acute ward patients are at risk of adverse events and patients recovering from critical illness are vulnerable to deterioration. Proactive and reactive strategies have been implemented to facilitate timely identification of patients at risk. Design., Systematic review. Methods., A range of data bases was searched from 2000,2008. Studies were eligible for review if they included adults in any setting where intensive care unit Liaison Nurse or Outreach services were provided. From 1423 citations and 65 abstracts, 20 studies met the inclusion criteria. Results., Intensive care liaison/outreach services had a beneficial impact on intensive care mortality, hospital mortality, unplanned intensive care admissions/re-admissions, discharge delay and rates of adverse events. A range of research methods were used; however, it was not possible to conclude unequivocally that the intensive care liaison/outreach service had resulted in improved outcomes. The major unmeasured benefit across all studies was improved communication pathways between critical care and ward staff. Outcomes for nurses in the form of improved confidence, knowledge and critical care skills were identified in qualitative studies but not measured. Conclusion., The varied nature of the intensive care liaison/outreach services reviewed in these studies suggests that they should be treated as bundled interventions, delivering a treatment package of care. Further studies should examine the impact of critical care support on the confidence and skills of ward nurses. Relevance to clinical practice., Advanced nursing roles can improve outcomes for patients who are vulnerable to deterioration. The Nursing Role Effectiveness Model provides a useful framework for evaluating the impact of these roles. [source]

Brain, mind, and dyadic change processes

Robert J. Neborsky
For many individuals attachment trauma is at the core of psychoneurosis and personality disorder. Combining theoretical aspects of psychodynamic therapy, developmental neuroscience, and attachment styles provides a useful framework for intensifying emotion and accelerating the course of treatment. A bihemispheric model is considered. The model addresses the challenge in treating the implicit trauma, which resides in the right hemisphere. This is achieved without resorting to interpretation, which is largely a left hemispheric process. The article presents a patient who benefits from a brief emotionally based psychotherapy that was completed after a course of a 20-year psychoanalysis. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 523,538, 2006. [source]

Closed loop folding units from structural alignments: Experimental foldons revisited

Sree V. Chintapalli
Abstract Nonoverlapping closed loops of around 25,35 amino acids formed via nonlocal interactions at the loop ends have been proposed as an important unit of protein structure. This hypothesis is significant as such short loops can fold quickly and so would not be bound by the Leventhal paradox, giving insight into the possible nature of the funnel in protein folding. Previously, these closed loops have been identified either by sequence analysis (conservation and autocorrelation) or studies of the geometry of individual proteins. Given the potential significance of the closed loop hypothesis, we have explored a new strategy for determining closed loops from the insertions identified by the structural alignment of proteins sharing the same overall fold. We determined the locations of the closed loops in 37 pairs of proteins and obtained excellent agreement with previously published closed loops. The relevance of NMR structures to closed loop determination is briefly discussed. For cytochrome c, cytochrome b562 and triosephophate isomerase, independent folding units have been determined on the basis of hydrogen exchange experiments and misincorporation proton-alkyl exchange experiments. The correspondence between these experimentally derived foldons and the theoretically derived closed loops indicates that the closed loop hypothesis may provide a useful framework for analyzing such experimental data. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010 [source]

Assessing patient category/dependence systems for determining the nurse/patient ratio in ICU and HDU: a review of approaches

PG Dip., Renee Adomat BA (Hons)
Background, A huge range of patient classification systems/tools are used in critical care units to inform workforce planning, however, they are not always applied appropriately. Many of these systems/tools were not originally developed for the purposes of workforce planning and so their use in determining the nurse:patient ratio required in critical care settings raises a number of issues for the organisation and management of these services. Aim, The aim of this paper is to review the three main assessment systems that are commonly used in critical care settings in the UK and evaluate their effectiveness in accurately determining nurse : patient ratios. If the application of these systems/tools is to enhance care, a thorough understanding of their origins and purpose is necessary. If this is lacking, then decisions relating to workload planning, particularly when calculating nurse : patient ratios, may be flawed. Conclusions, Patient dependency/classification systems and patient dependency scoring systems for severity of illness are robust measures for predicting morbidity and mortality. However, they are not accurate if used to calculate nurse : patient ratios because they are not designed to measure nursing input. Nursing intensity measures provide a useful framework for calculating the cost of providing a nursing service in critical care and can serve as a measure of nursing input, albeit a fairly basic one. However, many components of the nursing role are not ,accounted' for in these measures. Implications, The implications of these findings for the organization and management of critical care services are discussed. Careful consideration of these areas is vital if a cost efficient and cost-effective critical care service is to be delivered. [source]

X-ray birefringence and dichroism obtained from magnetic materials

S. W. Lovesey
In the past decade, synchrotron radiation has triggered a surge in studies of the polarization dependence of X-ray beams passing through non-isotropic materials. A vast range of experimental results concerning polarization-dependent absorption (dichroism) and dispersion (birefringence, for example) are available from materials which are either magnetic or exhibit preferred directions due to the local atomic environment. This article aims to bring together the diversity of modern experiments in this field with established methods of optical calculus, in a way that highlights the simplicity of the underlying physics. A useful framework is formed when observable quantities, in the X-ray case, are related to atomic variables of the sample material. Atomic descriptions of absorption spectra with various levels of complexity are considered, and some well documented sum-rules are encountered. The framework is the most general allowed within the electric dipole approximation. By way of illustration, dichroic X-ray absorption by two materials with highly anisotropic properties and magnetic ions with different valence shells are considered; namely, a 3d -transition ion in ferrous niobate, and a lanthanide ion in dysprosium borocarbide. Both materials display interesting magnetic properties that are challenging to interpret at an atomic level of detail, and it is shown how absorption experiments can contribute to resolving some issues. [source]

Scholarly work and the shaping of digital access

Carole L. Palmer
In the cycle of scholarly communication, scholars play the role of both consumer and contributor of intellectual works within the stores of recorded knowledge. In the digital environment scholars are seeking and using information in new ways and generating new types of scholarly products, many of which are specialized resources for access to research information. These practices have important implications for the collection and organization of digital access resources. Drawing on a series of qualitative studies investigating the information work of scientists and humanities scholars, specific information seeking activities influenced by the Internet and two general modes of information access evident in research practice are identified in this article. These conceptual modes of access are examined in relation to the digital access resources currently being developed by researchers in the humanities and neuroscience. Scholars' modes of access and their "working" and "implicit" assemblages of information represent what researchers actually do when gathering and working with research materials and therefore provide a useful framework for the collection and organization of access resources in research libraries. [source]

An introduction to the contemporary update

John H. Dunkle
While the higher education landscape has changed significantly over the past two decades, the AISP model remains a very useful framework for student affairs professionals at all levels. [source]

A scalar analysis of landscape connectivity

OIKOS, Issue 2 2003
Article first published online: 4 JUL 200
Landscape connectivity is critical to the maintenance of spatially-structured populations and consists of both a structural component, which describes the shape, size and location of landscape features; and a biological component, which consists of both the response of individuals to landscape features, and the patterns of gene flow that result from those individual responses. Traditional studies of landscape connectivity have attempted to discern individual behavioral responses to landscape features, but this methodology is intractable for many species. This paper is an attempt to relate the components of landscape connectivity through the explicit treatment of their spatial and temporal scales. Traditional measures of structural and biological components of connectivity are reviewed and more recently developed methods for the analysis of scale for each are introduced. I then present a framework for the comparison of scalar phenomena based on Watt's unit pattern, describe the potential outcomes of the comparison and discuss the implications of each. Several testable hypotheses emerge from the analysis that may serve as a useful framework for the investigation of landscape connectivity in the future. [source]

Optimal foraging on the roof of the world: Himalayan langurs and the classical prey model

Ken Sayers
Abstract Optimal foraging theory has only been sporadically applied to nonhuman primates. The classical prey model, modified for patch choice, predicts a sliding "profitability threshold" for dropping patch types from the diet, preference for profitable foods, dietary niche breadth reduction as encounter rates increase, and that exploitation of a patch type is unrelated to its own abundance. We present results from a 1-year study testing these predictions with Himalayan langurs (Semnopithecus entellus) at Langtang National Park, Nepal. Behavioral data included continuous recording of feeding bouts and between-patch travel times. Encounter rates were estimated for 55 food types, which were analyzed for crude protein, lipid, free simple sugar, and fibers. Patch types were entered into the prey model algorithm for eight seasonal time periods and differing age-sex classes and nutritional currencies. Although the model consistently underestimated diet breadth, the majority of nonpredicted patch types represented rare foods. Profitability was positively related to annual/seasonal dietary contribution by organic matter estimates, whereas time estimates provided weaker relationships. Patch types utilized did not decrease with increasing encounter rates involving profitable foods, although low-ranking foods available year-round were taken predominantly when high-ranking foods were scarce. High-ranking foods were taken in close relation to encounter rates, while low-ranking foods were not. The utilization of an energetic currency generally resulted in closest conformation to model predictions, and it performed best when assumptions were most closely approximated. These results suggest that even simple models from foraging theory can provide a useful framework for the study of primate feeding behavior. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source]

Practitioner Review: The Assessment and Treatment of Post-traumatic Stress Disorder in Children and Adolescents

Sean Perrin
Post-traumatic Stress Disorder (PTSD) is a syndrome defined by the intrusive re- experiencing of a trauma, avoidance of traumatic reminders, and persistent physiological arousal. PTSD is associated with high levels of comorbidity and may increase the risk for additional disorders over time. While controversies remain regarding the applicability of the PTSD criteria to very young children, it has proved to be a useful framework for guiding assessment and treatment research with older children and adolescents. This article presents an overview of the literature on the clinical characteristics, assessment, and treatment of PTSD in children and adolescents. [source]

An Analysis Paradigm for Investigating Multi-locus Effects in Complex Disease: Examination of Three GABAA Receptor Subunit Genes on 15q11-q13 as Risk Factors for Autistic Disorder.

A. E. Ashley-Koch
Summary Gene-gene interactions are likely involved in many complex genetic disorders and new statistical approaches for detecting such interactions are needed. We propose a multi-analytic paradigm, relying on convergence of evidence across multiple analysis tools. Our paradigm tests for main and interactive effects, through allele, genotype and haplotype association. We applied our paradigm to genotype data from three GABAA receptor subunit genes (GABRB3, GABRA5, and GABRG3) on chromosome 15 in 470 Caucasian autism families. Previously implicated in autism, we hypothesized these genes interact to contribute to risk. We detected no evidence of main effects by allelic (PDT, FBAT) or genotypic (genotype-PDT) association at individual markers. However, three two-marker haplotypes in GABRG3 were significant (HBAT). We detected no significant multi-locus associations using genotype-PDT analysis or the EMDR data reduction program. However, consistent with the haplotype findings, the best single locus EMDR model selected a GABRG3 marker. Further, the best pairwise genotype-PDT result involved GABRB3 and GABRG3, and all multi-locus EMDR models also selected GABRB3 and GABRG3 markers. GABA receptor subunit genes do not significantly interact to contribute to autism risk in our overall data set. However, the consistency of results across analyses suggests that we have defined a useful framework for evaluating gene-gene interactions. [source]

Stream order controls geomorphic heterogeneity and plant distribution in a savanna landscape

Abstract We posed the question: does viewing a savanna as a network of streams linked to a matrix of terrestrial hillslopes provide a useful framework to research and understand plant distribution in these landscapes? Our study area, the Phugwane River network, lies in the semi-arid savanna of Kruger National Park, South Africa. We examined changes in hillslope geomorphology from first-, third- and fifth-order hillslopes with regression equations. The distribution of geomorphic boundaries was enumerated by moving window analysis and the relationship between geomorphology and plant distribution was explored through ordination. First-order hillslopes had a simple geomorphology, fewer geomorphic boundaries and a relatively homogeneous plant assemblage. By contrast, fifth-order hillslopes were more complex in geomorphology, with more boundaries and a relatively heterogeneous vegetation pattern. Stream order classification of a savanna drainage network resulted in landscape units distinguishable by geomorphology, geomorphic boundaries and vegetation pattern. Therefore, the drainage network is a useful template to expose and organize the complexity in savanna landscapes into easily managed and researched units. This perspective should inform a shift from single-scale phytosociological views of homogeneous vegetation units towards multi-scale conceptualizations of savannas as water dependent ecosystems. [source]

Retention: An unresolved workforce issue affecting rural occupational therapy services

Anna Mills
Failure to retain health professionals in rural areas contributes to the poor health status of these communities through an inability to deliver reliable and consistent services. Considerable attention has been focused on factors affecting recruitment of health professionals. Far less is known about factors affecting the retention of occupational therapists. This was the focus of this study. Ethnographic interviews were used to explore the experiences of 10 occupational therapists who had left rural practice. Six themes emerged from the participants' experiences, from when they first considered rural practice to reflections following their departure from it. These themes were initial appeal, facing the challenge, rural practice issues, the social sphere, reasons for leaving and the value of rural experience. These factors gave rise to a proposed Model of Retention Equilibrium, which suggests that retention can be improved by addressing the imbalance between incentives to leave and incentives to stay. The model provides a useful framework for occupational therapists contemplating rural practice, as well as for health services managers responsible for service delivery in rural areas. [source]

Molecular evidence suggests an ancient radiation for the fairy shrimp genus Streptocephalus (Branchiopoda: Anostraca)

Phylogenetic relationships among assumed Gondwanan aquatic inland invertebrate fauna are generally largely neglected, and biogeographical hypotheses for these organisms are generally inferred from historic (palaeogeographical) and contemporary distribution patterns. The distribution of the monogeneric thermophilic freshwater fairy shrimp family Streptocephalidae (Streptocephalus) provides a particularly useful framework to test the three contrasting biogeographical scenarios proposed for the evolution of this group: (1) the genus evolved in Laurasia and subsequently dispersed into Africa and North America; (2) the genus evolved and dispersed out of Africa and (3) the current distribution of the genus is the result of vicariance following the fragmentation of Gondwana. In the present study, the phylogenetic relationships of species in this genus are examined with the use of two mitochondrial genes (12S rRNA and COI mtDNA), while the phylogenetic relationships among the North American species and selected African taxa was investigated using the nuclear fragment (5.8S-ITS-1-18S). Phylogenetic results indicate that Streptocephalus probably evolved in Gondwana and that the current distribution patterns are a consequence of a combination of vicariance and limited dispersal. The implications for the evolution of continental freshwater crustaceans are discussed. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82, 313,327. [source]

Panic comorbidity with bipolar disorder: what is the manic,panic connection?

Dean F MacKinnon
Context:, Bipolar/panic comorbidity has been observed in clinical, community and familial samples. As both are episodic disorders of affect regulation, the common pathophysiological mechanism is likely to involve deficits in amygdala-mediated, plasticity-dependent emotional conditioning. Evidence:, Neuronal genesis and synaptic remodeling occur in the amygdala; bipolar and panic disorders have both been associated with abnormality in the amygdala and related structures, as well as in molecules that modulate plasticity, such as serotonin, norepinephrine, brain-derived neurotrophic factor (BDNF) and corticotrophin releasing factor (CRF). These biological elements are involved in behavioral conditioning to threat and reward. Model:, Panic attacks resemble the normal acute fear response, but are abnormally dissociated from any relevant threat. Abnormal reward-seeking behavior is central to both manic and depressive syndromes. Appetites can be elevated or depressed; satisfaction of a drive may fail to condition future behavior. These dissociations may be the result of deficits in plasticity-dependent processes of conditioning within different amygdala subregions. Conclusions:, This speculative model may be a useful framework with which to connect molecular, cellular, anatomic and behavioral processes in panic and bipolar disorders. The primary clinical implication is that behavioral treatment may be critical to restore function in some bipolar patients who respond only partially to medications. [source]

Behind the Screen: The Role of State-TV Relationships in Russia, 1990,2000,

Les systèmes de régulation de la production des programmes télévisuels sont aussi importants dans les études des médias que l'analyse du corps d'un texte. l'économie politique rend possible l'étude des programmes télévisuels et des systèmes de régulation de la production télévisuelle dans un seul modèle de même que leurs interconnections. Deux systèmes régulateurs de télévision sont décrits, et les dynamiques de leur transformation sont présentées. Les résultats des entrevues avec les fonctionnaires de l'industrie télévisuelle sont utilisés pour examiner l'influence des relations entre l'État et les entreprises de télévision sur le contenu des programmes produits par la télévision russe entre 1990 et 2000. This paper argues that the content of television programs is influenced by how their production is organized and regulated. The political-economic approach provides a useful framework to link television programs and the regulation of TV production within a single model, and to investigate their interrelationship. Two systems of TV regulation are described in this paper and their evolution is discussed. Data from in-depth qualitative interviews with Russian television industry insiders are used to examine the impact of changes in the regulation of television on the types and content of programs produced between 1990 and 2000. [source]