Model theory of finite and pseudofinite groups

This is a survey, intended both for group theorists and model theorists, concerning the structure of pseudofinite groups, that is, infinite models of the first-order theory of finite groups. The focus is on concepts from stability theory and generalisations in the context of pseudofinite groups, and on the information this might provide for finite group theory

O caso da destruição das pinturas murais da sede da Fazenda Rialto, Bananal

This article is about the eighteenth century mural paintings at the headquarters of Fazenda Rialto, in Bananal, which were destroyed in 1996. These constituted one of the most important sets of ambient paintings with secular themes produced in the state of São Paulo during the period corresponding to the first cycle of coffee production. Orally attributed to the painter José Maria Villaronga y Panella, all that remains of these paintings are some photographs and dozens of fragments, impossible to reassemble. Studying the fragments of the paintings of Rialto as primary material documents, the main objective of this article is to identify the artistic, technical, and executive characteristics of three sets of murals attributed to a single painter. A methodology which combines laboratory tests and historical research on artistic techniques was adopted for objectively recognizing the artistic and artisan characteristics of the period and discussing the attribution of exclusive authorship to the work. The analytical systems adopted for this purpose were: examination with ultraviolet and infra-red radiation, optical microscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDS) to analyze its chemical elements. Issues related to the limitations on official Brazilian preservation activities for this category of artistic work were also discussed, reflecting on the development and changes in notions of historicity related to the preservation of works from the past and their methodological implications for conservation and restoration.Este artigo trata dos murais artísticos oitocentistas da sede da Fazenda Rialto, em Bananal, destruídos em 1996, que constituíam um dos mais importantes conjuntos de pinturas ambientais de temática profana produzidos no Estado de São Paulo no período correspondente ao primeiro ciclo da cultura do café. Atribuídas oralmente ao pintor José Maria Villaronga y Panella, dessas pinturas restaram apenas algumas fotografias e centenas de fragmentos, de impossível reassemblagem. Estudando-se os fragmentos de pintura da Rialto como documento material primário, o trabalho apresentado tem como principal objetivo a identificação das características artísticas e tecnoexecutivas de três conjuntos de murais tributados a um mesmo pintor. Para reconhecimento objetivo dos fazeres artístico-artesanais do período e discussão da atribuição de autoria exclusiva, adotou-se uma metodologia que combina exames laboratoriais e pesquisa histórica das técnicas artísticas. Os sistemas analíticos adotados para esse fim foram: exame com radiação ultravioleta e infravermelha, microscopia óptica, microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva (EDS) para análise química elementar. Discutem-se também questões relativas aos limites da ação preservacionista oficial brasileira sobre essa categoria de obra artística, refletindo sobre o desenvolvimento e as mudanças das noções de historicidade relativas à preservação dos bens do passado e suas implicações metodológicas nos conceitos de conservação e restauro

O território paulista na iconografia oitocentista: mapas, desenhos e fotografias. análise de uma herança cotidiana

This paper presents a study about the cartography elaborated to represent São Paulos territory during the 19th century. The author seeks to show the permanence of cultural values related to the colonial period by analyzing some cartographical models, which are not necessarily linked to a cartographic school. In this context, the author seeks to identify the formative values of the regional territorial space, the cultural identity of the common Man and the specific needs of his or her daily life

The profiling of MDMA tablets: a study of the combination of physical characteristics and organic impurities as sources of information

The profiling of MDMA tablets can be carried out using different sets of characteristics. The first type of measurements performed on MDMA tablets are physical characteristics (i.e. post-tabletting characteristics). They yield preliminary profiling data that may be valuable in a first stage for investigation purposes. However organic impurities (i.e. pre-tabletting characteristics) are generally considered to bring more reliable information, particularly for presentation of evidence in court. This work aimed therefore at evaluating the added value of combining pre-tabletting characteristics and post-tabletting characteristics of seized MDMA tablets. In approximately half of the investigated cases, the post-tabletting links were confirmed with organic impurities analyses. In the remaining cases, post-tabletting batches (post-TBs) were divided in several pre-tabletting batches (pre-TBs), thus supporting the hypothesis that several production batches of MDMA powder (pre-TBs) were used to produce one single post-TB (i.e. tablets having the same shape, diameter, thickness, weight and score; but different organic impurities composition). In view of the obtained results, the hypotheses were discussed through illustrating examples. In conclusion, both sets of characteristics were found relevant alone and combined together. They actually provide distinct information about MDMA illicit production and trafficking

A forensic science perspective on the role of images in crime investigation and reconstruction

This article presents a global vision of images in forensic science. The proliferation of perspectives on the use of images throughout criminal investigations and the increasing demand for research on this topic seem to demand a forensic science-based analysis. In this study, the definitions of and concepts related to material traces are revisited and applied to images, and a structured approach is used to persuade the scientific community to extend and improve the use of images as traces in criminal investigations. Current research efforts focus on technical issues and evidence assessment. This article provides a sound foundation for rationalising and explaining the processes involved in the production of clues from trace images. For example, the mechanisms through which these visual traces become clues of presence or action are described. An extensive literature review of forensic image analysis emphasises the existing guidelines and knowledge available for answering investigative questions (who, what, where, when and how). However, complementary developments are still necessary to demystify many aspects of image analysis in forensic science, including how to review and select images or use them to reconstruct an event or assist intelligence efforts. The hypothetico-deductive reasoning pathway used to discover unknown elements of an event or crime can also help scientists understand the underlying processes involved in their decision making. An analysis of a single image in an investigative or probative context is used to demonstrate the highly informative potential of images as traces and/or clues. Research efforts should be directed toward formalising the extraction and combination of clues from images. An appropriate methodology is key to expanding the use of images in forensic science

La Seine assainie, les poissons migrateurs et l’hydroélectricité

National audienceLes poissons migrateurs pourraient bénéficier de conditions favorables sur certains affluents de la Seine. Ces affluents sont équipés de nombreux moulins qui souhaitent bénéficier des opportunités offertes par la production d'énergie verte. Par contre les mesures réglementaires recommandés par la police de l'eau ne leur conviennent pas. La situation était bloquée mais l'intervention d'experts extérieurs au contexte permet de mettre en évidence des marges de progression

A methodology to event reconstruction from trace images

The widespread use of digital imaging devices for surveillance (CCTV) and entertainment (e.g., mobile phones, compact cameras) has increased the number of images recorded and opportunities to consider the images as traces or documentation of criminal activity. The forensic science literature focuses almost exclusively on technical issues and evidence assessment [1]. Earlier steps in the investigation phase have been neglected and must be considered. This article is the first comprehensive description of a methodology to event reconstruction using images. This formal methodology was conceptualised from practical experiences and applied to different contexts and case studies to test and refine it. Based on this practical analysis, we propose a systematic approach that includes a preliminary analysis followed by four main steps. These steps form a sequence for which the results from each step rely on the previous step. However, the methodology is not linear, but it is a cyclic, iterative progression for obtaining knowledge about an event. The preliminary analysis is a pre-evaluation phase, wherein potential relevance of images is assessed. In the first step, images are detected and collected as pertinent trace material; the second step involves organising and assessing their quality and informative potential. The third step includes reconstruction using clues about space, time and actions. Finally, in the fourth step, the images are evaluated and selected as evidence. These steps are described and illustrated using practical examples. The paper outlines how images elicit information about persons, objects, space, time and actions throughout the investigation process to reconstruct an event step by step. We emphasise the hypothetico-deductive reasoning framework, which demonstrates the contribution of images to generating, refining or eliminating propositions or hypotheses. This methodology provides a sound basis for extending image use as evidence and, more generally, as clues in investigation and crime reconstruction processes