987 resultados para Rendering apparatus.


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Caballeria liewi Lim, 1995, uses adhesive secretions from the head organs and posterior secretory systems to assist in locomotion and attachment. Ultrastructural investigations show that the head organs of C. liewi consist of three pairs of antero-lateral pit-like openings bearing microvilli and ducts leading from two types of uninucleated gland cells (located lateral to the pharynx), one type producing rod-like (S1) bodies with an electron-dense matrix containing less electron-dense vesicles and the second type producing oval (S2) bodies with a homogeneous electron-dense matrix. Interlinking band-like structures are observed between S1 bodies and between S2 bodies. S1 body is synthesised in the granular endoplasmic reticulum, transported to a Golgi complex to be packaged into vesicles and routed into ducts for exudation. The synthesis of the S2 body is unresolved. Haptoral secretions manifested externally as net-like structures are derived from dual electron-dense (DED) secretory body produced in the peduncular gland cells. The DED body consists of a less electron-dense oval core in a homogeneous electron-dense matrix. On exocytosis into the pyriform haptoral reservoir, DED bodies are transformed into a secretion with two types of inclusions (less electron-dense oval and electron-dense spherical inclusions) in an electron-dense matrix. The secretions are further transformed (as small, oval, electron-dense bodies) when transported to the superficial anchor grooves, and on exudation into the gill tissues, the secretions become an electron-dense matrix. Secretory bodies associated with uniciliated structures, anchor sleeves and marginal hooks are also observed.

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A microcosm system was developed to investigate transfers of organic xenobiotics in air-soil-plant systems. This was validated using 14C labelled 1,2-dichlorobenzene (DCB) as a model compound. Trapping efficiency was 106 ± 3% for volatile compounds and 93.0 ± 2.2% for carbon dioxide in a blank microcosm arrangement. Recovery of 1,2-dichlorobenzene spiked to grassed and unplanted soils was > 90% after 1 week. The predominant DCB loss process was volatilisation with no evidence for mineralisation over 1 week and 20-30% of the added spike remained in soil. Although there was no evidence for root uptake and translocation of added label, foliar uptake of soil volatilised compound was detected. The microcosm showed good potential for study of 14C labelled and unlabelled organic xenobiotic transfers in air-soil-plant systems with single plants and also intact planted cores.

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Painterly rendering has been linked to computer vision, but we propose to link it to human vision because perception and painting are two processes that are interwoven. Recent progress in developing computational models allows to establish this link. We show that completely automatic rendering can be obtained by applying four image representations in the visual system: (1) colour constancy can be used to correct colours, (2) coarse background brightness in combination with colour coding in cytochrome-oxidase blobs can be used to create a background with a big brush, (3) the multi-scale line and edge representation provides a very natural way to render fi ner brush strokes, and (4) the multi-scale keypoint representation serves to create saliency maps for Focus-of-Attention, and FoA can be used to render important structures. Basic processes are described, renderings are shown, and important ideas for future research are discussed.

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In this paper we present a brief overview of the processing in the primary visual cortex, the multi-scale line/edge and keypoint representations, and a model of brightness perception. This model, which is being extended from 1D to 2D, is based on a symbolic line and edge interpretation: lines are represented by scaled Gaussians and edges by scaled, Gaussian-windowed error functions. We show that this model, in combination with standard techniques from graphics, provides a very fertile basis for non-photorealistic image rendering.

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In this paper we explain the processing in the first layers of the visual cortex by simple, complex and endstopped cells, plus grouping cells for line, edge, keypoint and saliency detection. Three visualisations are presented: (a) an integrated scheme that shows activities of simple, complex and end-stopped cells, (b) artistic combinations of selected activity maps that give an impression of global image structure and/or local detail, and (c) NPR on the basis of a 2D brightness model. The cortical image representations offer many possibilities for non-photorealistic rendering.

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Painterly rendering (non-photorealistic rendering or NPR) aims at translating photographs into paintings with discrete brush strokes, simulating certain techniques (im- or expressionism) and media (oil or watercolour). Recently, our research into visual perception and models of processes in the visual cortex resulted in a new rendering scheme, in which detected lines and edges at different scales are translated into brush strokes of different sizes. In order to prepare a version which is suitable for many users, including children, the design of the interface in terms of window and menu system is very important. Discussions with artists and non-artists led to three design criteria: (1) the interface must reflect the procedures and possibilities that real painters follow and use, (2) it must be based on only one window, and (3) the menu system must be very simple, avoiding a jungle of menus and sub-menus. This paper explains the interface that has been developed.

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Complete image ontology can be obtained by formalising a top-down meta-language wich must address all possibilities, from global message and composition to objects and local surface properties.

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In this paper I outline possibilities for, and issues arising from, opposition towards the dominant ideologies and practices of marketing knowledge (Hirschman 1993) through an engagement with feminist epistemology (Longino 1991, Harding 1987). Feminist epistemology is a political branch of naturalised epistemology (Quine 1969) primarily concerned with critique of constructions of gender, gender norms and gendered interests within the production of knowledge (Anderson 1995) and with theorising, grounding and legitimating feminist knowledge making practices (Harding 1987). It is most often associated with the feminist critique of science, and with feminist science and technology studies (Haraway 1987, Wajman 1997). Feminist epistemology asks the question, ‘what is the nature of the feminist critical project as a way of knowing?’ (McLennan 1995:392). This paper outlines the basis of the feminist critique of knowledge generally, and as applied to marketing knowledge, offers description of the three main epistemological approaches to this question and suggestions for their application in practice. The paper progresses important work by consumer behaviour theorists (Bristor and Fischer 1993, Hirschman 1993) on the potentials of feminist ways of knowing for marketing and consumer behaviour by moving beyond the tripartite of feminist approaches outlined, and extending the discussion to take into account the development of situated knowledges theory (Haraway 1989, 1997), which has become so important in the decade since these papers were written. It joins ongoing conversations in consumer behaviour and marketing that share similar feminist concerns (Catterall et al 1997, 2000, 2005, Bettany and Woodruffe Burton 1999, 2005, and Hogg et al 1999, 2000) but in this contribution it takes a slightly tangential approach, seeing marketing knowledge in terms of its epistemic culture by using a model of masculinity in academic cultures from feminist theory (Wagner 1994) to help conceptualise it as such. The dominant masculine ideology of marketing knowledge both in execution (Penaloza 1994, Bristor and Fischer 1994, Fischer and Bristor 1993, Woodruffe 1996), and values (Hirschman 1993, Brown 2000, Desmond 1997) has been well documented over the past fifteen years. However, although the basis of this, how is it manifested and how a feminist informed marketing knowledge could be achieved, have been addressed somewhat in the literature (Bristor and Fischer 1993, Hogg, Bettany and Long 2000) an updated rendering is necessary which focuses specifically on epistemology and situates this discussion within a cultural framework. To do this I use the notions of cultural masculinity in academic disciplines developed by Wagner (1994) of ‘organisational egocentrism’, ‘fake collectivity’ and ‘de realisation’. With these, I raise important and specific issues around the notion of the masculinity of marketing knowledge, and then present an outline of feminist epistemologies to illustrate how different feminist approaches to knowledge would address these concerns.

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Besnoitia besnoiti and Toxoplasma gondii are two closely related parasites that interact with the host cell microtubule cytoskeleton during host cell invasion. Here we studied the relationship between the ability of these parasites to invade and to recruit the host cell centrosome and the Golgi apparatus. We observed that T. gondii recruits the host cell centrosome towards the parasitophorous vacuole (PV), whereas B. besnoiti does not. Notably, both parasites recruit the host Golgi apparatus to the PV but its organization is affected in different ways. We also investigated the impact of depleting and over-expressing the host centrosomal protein TBCCD1, involved in centrosome positioning and Golgi apparatus integrity, on the ability of these parasites to invade and replicate. Toxoplasma gondii replication rate decreases in cells over-expressing TBCCD1 but not in TBCCD1-depleted cells; while for B. besnoiti no differences were found. However, B. besnoiti promotes a reorganization of the Golgi ribbon previously fragmented by TBCCD1 depletion. These results suggest that successful establishment of PVs in the host cell requires modulation of the Golgi apparatus which probably involves modifications in microtubule cytoskeleton organization and dynamics. These differences in how T. gondii and B. besnoiti interact with their host cells may indicate different evolutionary paths.