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  Nova abordagem para a análise direta de matrizes em estado nativo por espectrometria de massas ambiente

  (Universidade Federal do Rio de Janeiro, 2026-08-13)

  Aguiar, Alexandre Narcelli Pestana de

  ;

  Costa, Gabriela Vanini

  ;

  Aquino Neto, Francisco Radler de

  ;

  http://lattes.cnpq.br/8181788948588711

  ;

  https://orcid.org/0000-0002-0501-8336

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  Chemical analyses using mass spectrometry have traditionally relied on sample preparation steps that consume time and resources. Extraction protocols, particularly for complex and diverse matrices, rarely recover all compounds of interest with equal efficiency. Direct Analysis in Real Time Mass Spectrometry (DART-MS) is an ambient ionization technique that has gained relevance across different fields of knowledge, but its potential for the direct analysis of raw samples (i.e., matrices in their native state, without extraction) remains limited by significant challenges, such as poor standardization and difficulties in sample handling/positioning, instrumental contamination, carryover, and thermal damage to the matrices. Thus, although DART-MS has gained considerable attention for its potential to enable analyses without sample preparation, most of its applications still involve extraction and processing protocols. The objective of this thesis was to develop a new analytical approach to overcome these challenges and, consequently, enable the direct analysis of raw matrices by DART-MS. The proposed strategy — named PERM (Permeably Enclosed Raw Matrices) — is based on confining the sample within a semipermeable enclosure coupled to a 3D-printed positioning device. The implementation of this new approach eliminated instrumental contamination, protected the samples from thermal damage, standardized the analytical process, and preserved the acquisition of informative chemical profiles without extraction, solubilization, or any other type of sample preparation. In addition, dedicated software was developed to address the specific demands that emerged from the newly introduced analytical system. The complete approach (concept, physical device, and software) was applied to and evaluated across a broad set of forensic, toxicological, and food-related matrices, with particular emphasis on its application to the chemical profiling of seized drugs, where it enabled the detection of high-value substances — e.g., synthetic-route markers, adulterants, and contaminants — that were not detected in the corresponding extracts analyzed by the extraction- based approach used by forensic authorities. A comprehensive methodological study demonstrated that simple parameters, such as temperature, analysis time, and positioning, can modulate the analytical response by orders of magnitude, enabling the selective enrichment of analytes without targeted extraction. Guidelines were proposed for establishing validation protocols for the direct analysis of raw matrices. Finally, the approach was further improved (PERM 2.0) to integrate automated sequential analyses in scanning mode (i.e., no longer in static mode), which increased sensitivity and markedly reduced the overall variability of the obtained signal. Altogether, PERM emerges as an innovative, low-cost approach that enables direct, rapid, and reliable qualitative analyses by DART-HRMS.

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  O protagonismo, a perseguição e a cassação de Marina São Paulo de Vasconcellos durante a ditadura civil-militar na UFRJ

  (Universidade de Varsóvia, 2026-06-30)

  Queiroz, Andréa Cristina de Barros

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  This article examines the pioneering role of Marina São Paulo de Vasconcellos as the first and only female full professor of Anthropology at the National School of Philosophy (FNFi) of the University of Brazil (UB), now the UFRJ. In addition to her career as a professor at the institution, her work toward the consolidation of Anthropology as an autonomous science and her tenure as director of the Institute of Philosophy and Social Sciences (IFCS) at UFRJ stand out - until she was affected by the authoritarianism and violence of the country’s civil-military dictator-ship, which not only persecuted her, forced her into retirement, and imprisoned her, but also pre-vented her from teaching at the very institution where she had been trained. Finally, the discussion explored how her legacy endures in places of memory and in the recollections of several generations of social scientists and historians both within and outside the University.

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  The 1st ABAP International Congress. Brazilian Society of Landscape Architects, Rio de Janeiro, Brazil, november 22-24

  (2006-12-01)

  Costa, Lúcia Maria Sá Antunes

  ;

  Pellegrino, Paulo

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  Is the right to mobility a right to the city? Examining a well-accepted planning paradigm

  (David Publishing Company, 2020)

  Lassance, Guilherme

  ;

  Figueira, Patricia

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  In many countries mobility is one of the pillars of public policies for urban development. The “right to mobility” has been assimilated to the very concept of the “right to the city” put forward by Henri Lefebvre a half century ago. However, based on recent surveys, the present paper intends to show that a greater offer of mobility can have the opposite effect of increasing the economic dependence of poor peripheries, thus contributing to the phenomenon of socio-spatial segregation. To show this perverse effect of mobility, we use the results drawn out from case studies located in the Metropolitan Region of Rio de Janeiro, Brazil. In this context, the areas with the greatest mobility offer correspond to those that are now more dependent and emptied of employment and daily urban life. This greater accessibility has the effect of transforming these better served areas into dormitory peripheries. In contrast, other areas, with much less mobility offer, are able to avoid this direct competition with the city center. In conclusion, the paper proposes a necessary revision of the concept of mobility as a foundation for urban development which became even more pressing under the current COVID-19 crisis.

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  Da weltanshauung à coisa: considerações sobre a sublimação no cinema e na música

  (Universidade Federal do Rio de Janeiro, 2026)

  Cunha, Daniel Szwarcfiter

  ;

  Oliveira, Fabio Malcher Martins de

  ;

  http://lattes.cnpq.br/4486166569128792

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