917 resultados para Lambert, David M.: Speciation and recognition concept.Theory and application
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Purpose – The purpose of this paper is to consider the current status of strategic group theory in the light of developments over the last three decades. and then to discuss the continuing value of the concept, both to strategic management research and practising managers. Design/methodology/approach – Critical review of the idea of strategic groups together with a practical strategic mapping illustration. Findings – Strategic group theory still provides a useful approach for management research, which allows a detailed appraisal and comparison of company strategies within an industry. Research limitations/ implications – Strategic group research would undoubtedly benefit from more directly comparable, industry-specific studies, with a more careful focus on variable selection and the statistical methods used for validation. Future studies should aim to build sets of industry specific variables that describe strategic choice within that industry. The statistical methods used to identify strategic groupings need to be robust to ensure that strategic groups are not solely an artefact of method. Practical implications – The paper looks specifically at an application of strategic group theory in the UK pharmaceutical industry. The practical benefits of strategic groups as a classification system and of strategic mapping as a strategy development and analysis tool are discussed. Originality/value – The review of strategic group theory alongside alternative taxonomies and application of the concept to the UK pharmaceutical industry.
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Le concept de test relationnel (test, en anglais ; Weiss et Sampson, 1986 [16]) est présenté. Ses origines dans les écrits de Freud sont brièvement retracées et son inscription dans la théorie des croyances pathogènes de Weiss présentée. Par ailleurs, les autres éléments de la théorie psychanalytique de Weiss sont présentés (buts thérapeutiques, obstacles, traumas, insight, test relationnel). Toutes ces étapes sont illustrées par des exemples tirés de la littérature. Un développement récent du concept de test relationnel est présenté et appliqué à la psychothérapie des troubles de la personnalité (Sachse, 2003 [14]). Finalement, les auteurs donnent deux brefs exemples de tests relationnels tirés de leur propre pratique de psychothérapeute et discutent des modèles en les comparant entre eux. Des conclusions concernant l'utilité du concept de test relationnel pour la pratique psychothérapeutique et la recherche en psychothérapie sont proposées. The test concept (Weiss and Sampson, 1986 [16]) is presented. Its origins in Freud's works are briefly evoked and its place within the theory of pathogenic beliefs by Weiss presented. We present also the remaining elements of Weiss' psychoanalytic theory which are objectives, obstacles, traumas and insight. Every step of the reflection is illustrated with case examples, drawn from the literature. A recent development of the test concept is presented and applied to the psychotherapy of personality disorders (Sachse, 2003 [14]). Finally, the authors give brief examples of tests having occurred in their own practice as psychotherapists and discuss the models by comparing them among each other. Conclusions are drawn concerning the usefulness of the test concept for psychotherapy practice and research.
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A longstanding debate in evolutionary biology concerns whether species diverge gradually through time or by rapid punctuational bursts at the time of speciation. The theory of punctuated equilibrium states that evolutionary change is characterised by short periods of rapid evolution followed by longer periods of stasis in which no change occurs. Despite years of work seeking evidence for punctuational change in the fossil record, the theory remains contentious. Further there is little consensus as to the size of the contribution of punctuational changes to overall evolutionary divergence. Here we review recent developments which show that punctuational evolution is common and widespread in gene sequence data.
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This essay analyses Zoë Wicomb's novel David's Story and her latest collection of short stories, The One That Got Away, through the lense of cosmopolitanism and Jacques Derrida's concept of ‘hauntology’. Wicomb is a cosmopolitan author in a very precise sense: an author who embeds locally specific stories in a complex intertextual, historical and transnational web of cross-references. As settings, characters and objects move between Scotland and South Africa, it appears that the histories of these countries are mutually haunted by each other. Uncanny encounters with the past, and with memorials and art objects that take on a spectral quality, evoke an increasing sense of disorientation on the part of protagonists and readers alike. Assumptions about place, history and identity are thus constantly undermined and reconfigured.
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We are delighted to have the opportunity to talk with Tony about how his work touches on issues of imitation and contagion—a loaded term unpacked within his 2013 book.
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This thesis attempts to provide deeper historical and theoretical grounding for sense-making, thereby illustrating its applicability to practical information seeking research. In Chapter One I trace the philosophical origins of Brenda Dervin’s theory known as “sense making,” reaching beyond current scholarship that locates the origins of sense-making in twentieth-century Phenomenology and Communication theory and find its rich ontological, epistemological, and etymological heritage that dates back to the Pre-Socratics. After exploring sense-making’s Greek roots, I examine sense-making’s philosophical undercurrents found in Hegel’s Phenomenology of Spirit (1807), where he also returns to the simplicity of the Greeks for his concept of sense. With Chapter Two I explore sense-making methodology and find, in light of the Greek and Hegelian dialectic, a dialogical bridge connecting sense-making’s theory with pragmatic uses. This bridge between Dervin’s situation and use occupies a distinct position in sense-making theory. Moreover, building upon Brenda Dervin’s model of sense-making, I use her metaphors of gap and bridge analogy to discuss the dialectic and dialogic components of sense making. The purpose of Chapter Three is pragmatic – to gain insight into the online information-seeking needs, experiences, and motivation of first-degree relatives (FDRs) of breast cancer survivors through the lens of sense-making. This research analyses four questions: 1) information-seeking behavior among FDRs of cancer survivors compared to survivors and to undiagnosed, non-related online cancer information seekers in the general population, 2) types of and places where information is sought, 3) barriers or gaps and satisfaction rates FDRs face in their cancer information quest, and 4) types and degrees of cancer information and resources FDRs want and use in their information search for themselves and other family members. An online survey instrument designed to investigate these questions was developed and pilot tested. Via an email communication, the Susan Love Breast Cancer Research Foundation distributed 322,000 invitations to its membership to complete the survey, and from March 24th to April 5th 10,692 women agreed to take the survey with 8,804 volunteers actually completing survey responses. Of the 8,804 surveys, 95% of FDRs have searched for cancer information online, and 84% of FDRs use the Internet as a sense-making tool for additional information they have received from doctors or nurses. FDRs report needing much more information than either survivors or family/friends in ten out of fifteen categories related to breast and ovarian cancer. When searching for cancer information online, FDRs also rank highest in several of sense-making’s emotional levels: uncertainty, confusion, frustration, doubt, and disappointment than do either survivors or friends and family. The sense-making process has existed in theory and praxis since the early Greeks. In applying sense–making’s theory to a contemporary problem, the survey reveals unaddressed situations and gaps of FDRs’ information search process. FDRs are a highly motivated group of online information seekers whose needs are largely unaddressed as a result of gaps in available online information targeted to address their specific needs. Since FDRs represent a quarter of the population, further research addressing their specific online information needs and experiences is necessary.
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Watson is a fully developed suburb of some 30 years in Canberra (the capital city of Australia), A plunge dip using arsenical pesticides for tick control was operated there between 1946 and 1960, Chemical investigations revealed that many soil samples obtained from the study area contained levels of arsenic exceeding the current health-based investigation levels of 100 mg kg(-1) set by the National Health and Medical Research Council in Australia, For the speciation study, nine composite samples of surface and sub-surface soils and a composite sample of rocks were selected. ICP-MS analysis showed that arsenic levels in these samples ranged from 32 to 1597 mg kg(-1), Chemical speciation of arsenic showed that the arsenite (trivalent) components were 0.32-56% in the soil and 44.8% in the rock composite samples. Using a rat model, the absolute bioavailability of these contaminated soils relative to As3+ or As5+ ranged from 1.02 to 9.87% and 0.26 to 2.98%, respectively, An attempt was made to develop a suitable leachate test as an index of bioavailability. However, the results indicated that there was no significant correlation between the bioavailability and leachates using neutral pH water or 1 M HCl. Our results indicate that speciation is highly significant for the interpretation of bioavailability and risk assessment data; the bioavailable fractions of arsenic in soils from Watson are small and therefore the health impact upon the environment and humans due to this element is limited.
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The removal of chemicals in solution by overland how from agricultural land has the potential to be a significant source of chemical loss where chemicals are applied to the soil surface, as in zero tillage and surface-mulched farming systems. Currently, we lack detailed understanding of the transfer mechanism between the soil solution and overland flow, particularly under field conditions. A model of solute transfer from soil solution to overland flow was developed. The model is based on the hypothesis that a solute is initially distributed uniformly throughout the soil pore space in a thin layer at the soil surface. A fundamental assumption of the model is that at the time runoff commences, any solute at the soil surface that could be transported into the soil with the infiltrating water will already have been convected away from the area of potential exchange. Solute remaining at the soil surface is therefore not subject to further infiltration and may be approximated as a layer of tracer on a plane impermeable surface. The model fitted experimental data very well in all but one trial. The model in its present form focuses on the exchange of solute between the soil solution and surface water after the commencement of runoff. Future model development requires the relationship between the mass transfer parameters of the model and the time to runoff: to be defined. This would enable the model to be used for extrapolation beyond the specific experimental results of this study. The close agreement between experimental results and model simulations shows that the simple transfer equation proposed in this study has promise for estimating solute loss to surface runoff. Copyright (C) 2000 John Wiley & Sons, Ltd.
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Mosquito collections were made throughout the mainland of Papua New Guinea to identify the members of the Anopheles punctulatus group present and to determine their distribution. Identification was made using morphology, DNA hybridization, and polymerase chain reaction (PCR)-RFLP analysis. Nine members of the group were identified: An. farauti s.s. Laveran, An.farauti 2, An. koliensis Owen, and An. punctulatus Donitz, were common and widespread; An. farauti 4 was restricted to the north of the central ranges where it was common; An. farauti 6 was found only in the highlands above 1,000 m; and An. farauti 3, An. sp. near punctulatus and An. clowi Rozeboom & Knight were uncommon and had restricted distributions. Identification of An. koliensis and An. punctulatus using proboscis morphology was found to be unreliable wherever An. farauti 4 occurred. The distribution and dispersal of the members of the An. punctulatus group is discussed in regard to climate, larval habitats, distance from the coast, elevation, and proximity to human habitation.
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A radiation of five species of giant tortoises (Cylindraspis ) existed in the southwest Indian Ocean, on the Mascarene islands, and another (of Aldabrachelys ) has been postulated on small islands north of Madagascar, from where at least eight nominal species have been named and up to five have been recently recognized. Of 37 specimens of Madagascan and small-island Aldabrachelys investigated by us, 23 yielded significant portions of a 428-base-pair (bp) fragment of mitochondrial (cytochrome b and tRNA-Glu), including type material of seven nominal species (A. arnoldi, A. dussumieri, A. hololissa, A. daudinii, A. sumierei, A. ponderosa and A. gouffei ). These and nearly all the remaining specimens, including 15 additional captive individuals sequenced previously, show little variation. Thirty-three exhibit no differences and the remainder diverge by only 1-4 bp (0.23-0.93%). This contrasts with more widely accepted tortoise species which show much greater inter- and intraspecific differences. The non-Madagascan material examined may therefore only represent a single species and all specimens may come from Aldabra where the common haplotype is known to occur. The present study provides no evidence against the Madagascan origin for Aldabra tortoises suggested by a previous molecular phylogenetic analysis, the direction of marine currents and phylogeography of other reptiles in the area. Ancient mitochondrial DNA from the extinct subfossil A. grandidieri of Madagascar differs at 25 sites (5.8%) from all other Aldabrachelys samples examined here.