A região cárstica de Lagoa Santa (Minas Gerais) contém dezenas de sítios arqueológicos, cujos mais antigos datam do Holoceno Inicial (período entre 10.000 e 7000 anos A.P.), com coleções numerosas de remanescentes esqueletais humanos bem preservados. O sítio em abrigo Lapa do Santo, localizado ao norte do carste, contém mais de 30 sepultamentos humanos escavados, tendo sido identificadas práticas funerárias complexas que incluem o descarnamento, a decapitação e a remoção intencional de dentes. A matriz sedimentar que contém os vestígios é constituída de cinzas de antigas estruturas de combustão, acesas em um período de 3000 anos. Muitos artefatos líticos foram escavados no sítio, a maioria com pequenas dimensões (comprimento com cerca de 22 mm). Os líticos do sítio são lascas (raramente retocadas), núcleos e resíduos de lascamento, grande parte produzidos com cristais de quartzo hialino. Estudos tecnológicos e experimentais prévios sugerem que os líticos seriam usados para cortar e raspar materiais pequenos e macios, como plantas. Nesta pesquisa, para verificar o uso dos líticos da Lapa do Santo para o processamento de plantas, foram realizadas análises de microvestígios botânicos (fitólitos e amido) recuperados em 20 líticos do sítio. Esses artefatos foram recuperados de três unidades de escavação diferentes e do contexto de um sepultamento, seguindo um protocolo específico para evitar a contaminação durante a coleta. Amostras de sedimento do sítio também foram analisadas para verificar a possível contaminação dos microvestígios retidos nos líticos com os microvestígios presentes no sedimento. As análises revelaram fitólitos nos líticos (n = 19) e no sedimento (em todas as amostras), assim como amido na maioria dos líticos (n = 16) e em uma única amostra de sedimento. Os morfotipos de fitólitos identificados são diagnósticos dos seguintes táxons de plantas: Aristidoideae, Bambusoideae, Chloridoideae, Arecaceae (palmeiras), Poaceae (gramíneas) incluindo Panicoideae e, dentre essas, Zea mays (milho), Cyperaceae, inclusive Cyperus/Kyllinga sp; Zingiberales e Eudicotiledôneas (arbóreas). Os grãos de amido identificados apresentam semelhanças, embora nem sempre totalmente, com aqueles pertencentes aos táxons: Araceae (taioba), Arecaceae, Poaceae incluindo gramíneas selvagens e Zea mays; Ipomoea batatas (batata-doce), Capsicum sp. (pimenta e pimentão) e Dioscorea sp. (cará). Os resultados indicam que os instrumentos foram usados para processar plantas amiláceas cruas. Na quadra N23 quase todos os fitólitos que estão presentes nos líticos estão presentes também no sedimento (com exceção de Cyperaceae, presentes nos líticos, mas não no sedimento). Isso sugere uma possível contaminação dos líticos com os fitólitos do sedimento. Na quadra P11 há fitólitos de dois táxons de plantas (Aristidoideae e Zingiberales) nos líticos que não estão presentes no sedimento. Na quadra AE1 há fitólitos de quatro táxons de plantas (Bambusoideae, Chloridoideae, Cyperus/Kyllinga sp. e Zingiberales) nos líticos, que não estão presentes no sedimento ao redor. A presença exclusiva desses fitólitos nos líticos das quadras P11 e AE1, mas não no sedimento, indica que tais plantas foram, de fato, processadas com os artefatos. / The karstic region of Lagoa Santa (Minas Gerais state) contains several archaeological sites dating back to the early Holocene with an astonishing number of well-preserved human remains. The Lapa do Santo rockshelter site, in the northern part of the karst, contains more than 30 human interments in which complex funerary rituals were identified, including defleshing, decapitation and intentional teeth removal. The sedimentary matrix containing the skeletal remains is mostly made of ashes from ancient combustion structures, lit within a period of about 3000 years. Several lithic artifacts have been recovered from the site, most of them of small dimensions (length around 22 mm). Lithics are mostly flakes (rarely retouched), cores and splinters made from single crystals of hyaline quartz. Previous technological research suggests that lithic artifacts were used to cut and scrape small and soft materials, like plants. To verify whether the lithics from Lapa do Santo were indeed used to process plant resources, analyses of plant microremains (phytoliths and starch) were undertaken in 20 artifacts from the site. The artifacts were recovered from three different excavation units (1 m x 1 m) and one interment, following a specific protocol to prevent contamination during collection. Sediment samples from the site were also analyzed in order to differentiate between microremains retained in the lithics after their use or incorporated later from the surrounding sediments. The analyses revealed a larger amount of phytoliths in the lithics (19 of them) and sediment (all samples) and starch in most of the artifacts (16 of them) and in one sediment sample. The identified phytolith morphotypes are diagnostic of the following plant taxa: Aristidoideae, Bambusoideae, Chloridoideae, Arecaceae, Poaceae, including Panicoideae and among these, Zea mays (corn), Cyperaceae, including Cyperus/Kyllinga sp; Zingiberales and Eudicots. The starch grains show resemblances (even though not completely sometimes) to those belonging to: Araceae, Arecaceae, Poaceae, including wild grasses and Zea mays, Ipomoea batatas, Capsicum sp. and Dioscorea sp. The results indicate that the instruments were used to process raw (non cooked) starchy plants. Almost every phytolith from the N23 excavation unit that are present in lithics, are also present in the sediment from this unit (except the ones of Cyperaceae, present in lithic but not in the sediment), which strongly suggest contamination of the lithics with the phytoliths and starch from the sediment. From the P11 excavation unit there are phytolithis of two plant taxa (Aristidoideae and Zingiberales) in the lithics that are not present in the sediment. From the AE1 excavation unit there are phytoliths from four plant taxa (Bambusoideae, Chloridoideae, Cyperus/Kyllinga sp. and Zingiberales) in the lithics that are not present in the sediment. This suggests that the phytoliths in these artifacts may have been originated by their use and not by contamination with the sediment.

Les systèmes multi-agents sont des systèmes dans lesquels des entités logiciellesappelées agents interagissent de façon autonome dans des environnements partagés. Ces dernièresannées, de nombreuses recherches sur les organisations multi-agents ont été menées etdivers modèles organisationnels ont été proposés. Cependant, ils n’offrent pas de solution pourune gestion effective de la problématique d’ouverture dans des organisations multi-agents normatives.Dans cette thèse, nous nous sommes intéressées à l’étude de cette problématique etdonc à la spécification des besoins relatifs à la mise en oeuvre de l’ouverture au sein d’organisationmulti-agent. Nous avons ainsi identifié trois propriétés caractéristiques de cette problématique: l’interopérabilité d’une organisation avec son environnement extérieur et interne, lagestion des entrées / sorties et la gestion du contrôle et de la régulation des agents. Pour répondreà ces propriétés, nous avons proposé un langage de modélisation d’organisation (OML)MOISE qui est une extension de Moise+. MOISE permet de spécifier de façon explicite lesprocessus d’entrée / sortie dans une organisation et notamment les exigences relatives auxmissions, buts, et rôles de l’organisation. Nous avons également proposé une infrastructure degestion d’organisation (OMI) ORA4MAS qui s’inspire du méta-modèle Agents et Artifacts(A&A). Nous avons défini le concept d’artefact organisationnel pour implémenter les fonctionnalitéscorrespondant aux spécifications du langage MOISE. Nos propositions ont été illustréesavec une spécification d’organisation de gestion de la construction d’un édifice. La miseen oeuvre des propriétés d’ouverture a été expérimentée avec la gestion des processus d’entrée/ sortie des agents, la négociation des clauses de contrat, la coordination des coopérations desagents à la réalisation des buts de construction d’un édifice, le contrôle des comportements desagents relativement aux normes de l’organisation ainsi que leur régulation. / Multi-Agent Technology concerns the development of decentralized and open systemscomposed of different agents interacting in a shared environment. In recent years, organizationhas become an important in this research field. Many models have been, and are still,proposed. While no concensual model emerges of these different works, it appears that theyall lack the ability to build open and normative organizations in the sense of management ofentry / exit of agents into organization but also decentralized control / regulation of the autonomyof the agents. In this thesis, our objective consists in the definition of a new modeladdressing these requirements. Ours reseaches allow us to extend theMOISE+ organizationalmodeling language (OML) in a new version namming MOISE. In this one we define an Entry/ Exit specification allowing to explicitly specify the ways in which the agents can enter orexit in or from an organisation by providing some requirements according to the missions, thegoals and the roles of the organisation. The organizational management infrastructure (OMI)ORA4MAS proposed take advantage of the Agents and Artifacts (A&A) approach. We definedthe Organizational Artifacts concept as the basic building block of our OMI for themanagement of organized and open MAS. To focus our study, the organizational artifacts willbe defined considering the OML specification of the MOISE model. We experimented ourproposal with the specification of an application aiming to manage the build of a house. Wethen experimented the management of the candidate agents to enter in the organisation and cooperatewith the other to build the house according to a specified social scheme, the specifiednorms and their contract clauses negociated when they will be admitted in the organisation.

As the artwork’s title suggests, Penelope Umbrico’s "Mirrors (from Home Décor Catalogs and Websites)" (2001-2011), are photographs of mirrors that Umbrico has appropriated from print and web based home décor advertisements like those from Pottery Barn or West Elm. The mirrors in these advertisements reflect the photo shoot constructed for the ad, often showing plants or light filled windows empty of people. To print the "Mirrors," Umbrico first applies a layer of white-out to everything in the advertisement except for the mirror and then scans the home décor catalog. In the case of the web-based portion of the series, she removes the advertising space digitally through photo editing software. Once the mirror has been singled out and made digital, Umbrico then adjusts the perspective of the mirror so that it faces the viewer. Finally, she scales the photograph of the mirror cut from the advertisement to the size and shape of the actual mirror for sale. By enlarging the photograph, she must increase the file size and subsequent print significantly, which distorts the final printed image thereby causing pixelation, otherwise known as “compression artifacts.” Lastly, she mounts these pixelated prints to non-glare Plexiglas both to remove any incidental reflective surface effects and to create a physical object. What hangs on the wall, then, looks like a mirror in its shape, size and beveled frame: the photograph becomes a one-to-one representation of the object it portrays. When looking at a real mirror, often the viewer is aware of either a reflection of the self or a shifting reflection caused by his or her own movement. However, the image that the "Mirror" ‘reflects’ is not the changing reflection of a real mirror. Nor is it a clear, fixed image of the surface of a mirror. Instead the "Mirrors" present a highly abstract, pixelated surface to meet our eyes. The "Mirrors" are physical objects that merge two forms of representation into one: the mirror and the photograph, thus highlighting similarities between them as surfaces that can potentially represent or reflect almost anything. However, in their physical form, they show us only their pixelation, their digitally constructed nature. Penelope Umbrico’s "Mirrors" are photographs of mirrors that become simultaneously photograph and mirror: the image reflected on the mirror’s surface becomes a photograph, thus showing an analogy between the two objects. In their self-reflexive nature, I argue that Umbrico’s "Mirrors" point to their status as digital photographs, therefore signaling a technological shift from analog to digital photography. Umbrico’s "Mirrors," in altering both mirrors and photographs simultaneously refer to the long history of photography in relation to mirrors. The history of photography is seen first through these objects by the reflective surface of the daguerreotype which mirrored the viewer when observing the daguerreotype, and because of the extremely high level of detail in the photographic image, which mirrored the photographic subject. The relation to the history of photography is also seen in the phenomenon of the mirror within a photograph and the idea that the mirror’s reflection shows the realistic way that photographs represent reality. Craig Owens calls this "en abyme," or the miniature reproduction of a text that represents the text as a whole. In the case of the mirror, this is because the mirror within the photograph shows how both mediums display highly naturalistic depictions of reality. I contend that as an object that is representative of the photographic medium itself, the shift from analog to digital photography is in part seen through the use of the mirror that ultimately creates an absent referent as understood through a comparison of Diego Velázquez’s "Las Meninas" (1656). As Foucault suggests that "Las Meninas" signals a shift in representation from the Classical age to the Modern period, I suggest that the "Mirrors" signal the shift in representation from analog to digital. This latter shift spurred debate among photo history scholars related to the ontology of the photographic medium as scholars were anxious that the ease of editing digital images compromised the photograph’s seeming relationship to truth or reality and that it would be impossible to know whether an image had been altered. They were also concerned with the idea that computers could generate images from nothing but code, removing the direct relationship of the photograph to its subject and thereby declaring the “death” of the medium. The "Mirrors" embody the technological phenomenon with visual addition of “compression artifacts,” otherwise known as pixelation, where this representation of digital space appears not directly from our own creation but as a by-product of digital JPEG programming. In this way they are no longer connected to the subject but only to the digital space they represent. As self-reflexive objects, the "Mirrors" show that there has been a technological transformation from the physically made analog photograph to the inherently mutable digital file.

Taking my own personal history as a starting point this paper will look at how we inherit culture and in turn shape it through the stories and objects that drive its formation. This extends into how these objects proliferate within our culture and the way in which the passing of History impacts on the way we view them and as a consequence ourselves as individuals and as a group. Identity is then passed on through generations through the act of storytelling, and this process is integral to this research paper. This is also a personal journey, taking place in varying sites, from a rusting car hulk in a back yard in North Canterbury, to a University in Wellington and another rusted car, which has gone through a strange restoration. The Morris Minor has been embraced as a narcissistic object that I have chosen to double in order to explore my individual and wider national cultural history and identity. One of the key themes of this inherited identity is largely based around Nostalgia for an ideal past. This ideal is a fiction, a layering of intended futures as well as a selective past. This works in the same way as the modern artistic preoccupation with gothic histories, but instead of a positive ideal we have the creation of a basement of horrors that lurks beneath the surface. Be it positivist idealism or Gothic inversion, one way of focusing on the way these fictions differ markedly from the reality of the objects existence, is to show the artifice of the stories told by enhancing the components of the story that are already exaggerated, for the Morris Minor this means getting as far away from its existence as a rusting hulk in the backyard as possible. The longing for a past that may or may not exist, is less important as existing in reality but instead for what these fictions supply in their retelling. The concept of the Uncanny is integral to this retelling of memory, in that through a memories reanimation it can only approximate the original event leaving gaps for circumspection and invention. This retelling necessitates a reorientation in the relationship between the teller of the tale and the listener and between the viewer and the object viewed. The research culminates in the alteration of a Morris Minor to appear as one continuous surface. The intention of which is to engage with the differing versions of the objects past through taking an active part in its reconstruction as artwork with the aim of reassessment not only of my individual approach to the object but also the viewers.

Taking my own personal history as a starting point this paper will look at how we inherit culture and in turn shape it through the stories and objects that drive its formation. This extends into how these objects proliferate within our culture and the way in which the passing of History impacts on the way we view them and as a consequence ourselves as individuals and as a group. Identity is then passed on through generations through the act of storytelling, and this process is integral to this research paper. This is also a personal journey, taking place in varying sites, from a rusting car hulk in a back yard in North Canterbury, to a University in Wellington and another rusted car, which has gone through a strange restoration. The Morris Minor has been embraced as a narcissistic object that I have chosen to double in order to explore my individual and wider national cultural history and identity. One of the key themes of this inherited identity is largely based around Nostalgia for an ideal past. This ideal is a fiction, a layering of intended futures as well as a selective past. This works in the same way as the modern artistic preoccupation with gothic histories, but instead of a positive ideal we have the creation of a basement of horrors that lurks beneath the surface. Be it positivist idealism or Gothic inversion, one way of focusing on the way these fictions differ markedly from the reality of the objects existence, is to show the artifice of the stories told by enhancing the components of the story that are already exaggerated, for the Morris Minor this means getting as far away from its existence as a rusting hulk in the backyard as possible. The longing for a past that may or may not exist, is less important as existing in reality but instead for what these fictions supply in their retelling. The concept of the Uncanny is integral to this retelling of memory, in that through a memories reanimation it can only approximate the original event leaving gaps for circumspection and invention. This retelling necessitates a reorientation in the relationship between the teller of the tale and the listener and between the viewer and the object viewed. The research culminates in the alteration of a Morris Minor to appear as one continuous surface. The intention of which is to engage with the differing versions of the objects past through taking an active part in its reconstruction as artwork with the aim of reassessment not only of my individual approach to the object but also the viewers.

<p>Three-dimensional rotational angiography (3D-RA) is an established method within the field of interventional neuroradiology. The method has also a great potential in other areas with a complicated arterial anatomy. The purpose of this study was firstly to develop an investigative protocol for 3D-RA in renal transplanted patients with threatening allograft failure in diagnosing stenosis in the transplanted renal artery; secondly the protocol was evaluated and compared with a modified protocol including reduced contrast medium load. Furthermore, the advantages of the 3D reconstructions compared to the angiographic images were evaluated, likewise if an extended angle of rotation reduced the artifacts in the 3D reconstructions. The two protocols were compared with regard to image quality and acute nephrotoxicity. The accuracy of Doppler ultrasonography and the result of percutaneous transluminal angioplasty (PTA) were also assessed.</p><p>3D-RA was consecutively performed in 57 renal transplanted patients with suspicion of renal artery stenosis. A significant stenosis was found in 49% of the patients. The 3D reconstructions profiled 43% of the transplant renal artery stenoses better than the angiographic images. An extended angle of rotation reduced the artifacts. There was no statistical difference regarding image quality between the two protocols, and the renal function was equally affected in both protocols. Doppler ultrasonography sensitivity was 100%; specificity was 48% and positive predictive value 67%. PTA had a technical success rate of 92% and a clinical success rate of 75% after 3 months.</p><p>3D-RA is a helpful supplement in cases with complicated vascular anatomy, especially when PTA may be indicated. The 3D reconstructions profile the course of the artery more frequently than the angiographic images and support PTA. The 3D reconstructions are degraded of artifacts. Sampling artifacts can be diminished by increased C-arm rotation and increased number of projections. The distortions caused by beam hardening remain to be solved.</p>

Three-dimensional rotational angiography (3D-RA) is an established method within the field of interventional neuroradiology. The method has also a great potential in other areas with a complicated arterial anatomy. The purpose of this study was firstly to develop an investigative protocol for 3D-RA in renal transplanted patients with threatening allograft failure in diagnosing stenosis in the transplanted renal artery; secondly the protocol was evaluated and compared with a modified protocol including reduced contrast medium load. Furthermore, the advantages of the 3D reconstructions compared to the angiographic images were evaluated, likewise if an extended angle of rotation reduced the artifacts in the 3D reconstructions. The two protocols were compared with regard to image quality and acute nephrotoxicity. The accuracy of Doppler ultrasonography and the result of percutaneous transluminal angioplasty (PTA) were also assessed. 3D-RA was consecutively performed in 57 renal transplanted patients with suspicion of renal artery stenosis. A significant stenosis was found in 49% of the patients. The 3D reconstructions profiled 43% of the transplant renal artery stenoses better than the angiographic images. An extended angle of rotation reduced the artifacts. There was no statistical difference regarding image quality between the two protocols, and the renal function was equally affected in both protocols. Doppler ultrasonography sensitivity was 100%; specificity was 48% and positive predictive value 67%. PTA had a technical success rate of 92% and a clinical success rate of 75% after 3 months. 3D-RA is a helpful supplement in cases with complicated vascular anatomy, especially when PTA may be indicated. The 3D reconstructions profile the course of the artery more frequently than the angiographic images and support PTA. The 3D reconstructions are degraded of artifacts. Sampling artifacts can be diminished by increased C-arm rotation and increased number of projections. The distortions caused by beam hardening remain to be solved.

Contrast-enhanced mammography (CEM) relies on visualizing the growth of new blood vessels (i.e. tumor angiogenesis) to provide sufficient materials for cell proliferation during the development of cancer. Since cancers will accumulate an injected contrast agent more than other tissues, it is possible to use one of several methods to enhance the area of lesions in the x-ray image and remove the contrast of normal tissue. Large area flat panel detectors may be used for CEM wherein the subtraction of two acquired images is used to create the resulting enhanced image. There exist several methods to acquire the images to be subtracted, which include temporal subtraction (pre- and post-contrast images) and dual-energy subtraction (low- and high-energy images), however these methods suffer from artifacts due to patient motion between image acquisitions. In this research the use of a multilayer flat panel detector is examined for CEM that is designed to acquire both (low- and high-energy) images simultaneously, thus avoiding motion artifacts in the resulting subtracted image. For comparison, a dual-energy technique prone to motion artifacts that uses a single-layer detector is also investigated. Both detectors are evaluated and optimized using amorphous selenium as the x-ray to charge conversion material, however the theoretical analysis could be extended to other conversion materials. Experimental results of single pixel prototypes of both multilayer and single-layer detectors are also discussed and compared to theoretical results. For a more comprehensive analysis, the motion artifacts present in dual-exposure techniques are modeled and the performance degradation due to motion artifacts is estimated. The effects of noise reduction techniques are also evaluated to determine potential image quality improvements in CEM images.

Magnetic resonance imaging (MRI) is a very versatile imaging modality which can be used to acquire several different types of images. Some examples include anatomical images, images showing local brain activation and images depicting different types of pathologies. Brain activation is detected by means of functional magnetic resonance imaging (fMRI). This is useful e.g. in planning of neurosurgical procedures and in neurological research. To find the activated regions, a sequence of images of the brain is collected while a patient or subject alters between resting and performing a task. The variations in image intensity over time are then compared to a model of the variations expected to be found in active parts of the brain. Locations with high correlation between the intensity variations and the model are considered to be activated by the task. Since the images are very noisy, spatial filtering is needed before the activation can be detected. If adaptive filtering is used, i.e. if the filter at each location is adapted to the local neighborhood, very good detection performance can be obtained. This thesis presents two methods for adaptive spatial filtering of fMRI data. One of these is a modification of a previously proposed method, which at each position maximizes the similarity between the filter response and the model. A novel feature of the presented method is rotational invariance, i.e. equal sensitivity to activated regions in different orientations. The other method is based on bilateral filtering. At each position, this method averages pixels which are located in the same type of brain tissue and have similar intensity variation over time. A method for robust correlation estimation is also presented. This method automatically detects local bursts of noise in a signal and disregards the corresponding signal segments when the correlation is estimated. Hence, the correlation estimate is not affected by the noise bursts. This method is useful not only in analysis of fMRI data, but also in other applications where correlation is used to determine the similarity between signals. Finally, a method for correcting artifacts in complex MR images is presented. Complex images are used e.g. in the Dixon technique for separate imaging of water and fat. The phase of these images is often affected by artifacts and therefore need correction before the actual water and fat images can be calculated. The presented method for phase correction is based on an image integration technique known as the inverse gradient. The method is shown to provide good results even when applied to images with severe artifacts.

The purpose with this study is to identify an organizational culture at Posten Örebro based on Edgar H. Schein´s theory about the three levels of culture. These three levels consist of artifacts, espoused beliefs and values and basic underlying assumptions. Artifacts represent the visible and tangible of an organization and this level is the easiest level to identify. Espoused beliefs and values include common thoughts and ideals within the organization and are an aware, but not necessarily material, cultural level. The essence of a culture contains basic underlying assumptions that influence underlying thoughts and actions and this is a level that is difficult to identify since it is unaware to the members of an organization. This study will also examine the organizational culture’s level of homogeneity among departments and employee levels within Posten Örebro.This study is based on the following questions: How can the organizational culture of Posten Örebro be described based on Schein´s levels of culture? How homogenous is the organizational culture among departments and employee levels within Posten Örebro?The result of this study shows that it is possible to apply Schein´s theory on Posten Örebro and to identify artifacts, espoused beliefs and values and an indication of a basic underlying assumption. The result also shows that the organizational culture within Posten Örebro is almost completely homogenous, with the exception of the value of change.Key words: Organizational culture, Schein, Posten, artifacts, espoused values, underlying assumptions