Applying pyrolysis-gas chromatography/mass spectrometry to the identification of oriental lacquers: study of two lacquered shields

Oriental lacquers have been used as coating materials for thousands of years for wooden, ceramics, leather and metal objects. Lacquers are natural polymers obtained from three species growing in different regions of Asia: Rhus vernicifera (China, Japan and Korea); Rhus succedanea (Vietnam and Taiwan); and Melanorrhoea usitate (Myanmar and Thailand). The identification of lacquer films is important for conservation and restoration purposes, as well as for art history studies because it may help in determining the origin of the lacquered objects. In this work, pyrolysis-gas chromatography/mass spectrometry using a filament-type pyrolyser was successfully applied to the characterization of oriental lacquers. A method to identify the three kinds of lacquer was developed and applied to the study of two lacquered shields imported from Asia in the sixteenth century. The materials that constitute the shields were also examined by Fourier-transform infrared microspectroscopy and details of the lacquering technique are reporte

Consentimento informado em pesquisa científica: o que devemos saber?

Informed consent is a pillar of the research and imperative in an ethical dimension. Given its inherent principles in an increasingly rigorous and responsible investigation, this process is complex, making it challenging to reflect on its validity from an ethical and deontological perspective. We are witnessing the fast development of knowledge in biomedicine intrinsic to unprecedented technological innovation, with increased complex studies and repercussions on consent. Among them, the simplification and validation of information to be transmitted to the participant, the possibility to extend the period for clarifying possible doubts, the use of support tools, and optimization of the communication by researchers. Overly technical terms, difficult interpretation of the information, little explanation, different cultures, and sociopolitical ideologies affect the researchers’ differentiation. Given the several legal dimensions of consent, the relevance of free and informed exercise of the rights provided by law for scientific development in health was demonstrated. In addition to an opportunity for effective communication, informed consent must be based on a trust relationship between the investigator and the participant, based on ethical principles. These are essential to the development of rational and robust research, somehow guiding the work to be carried out by researchers, including the principles of beneficence, non-maleficence, justice, autonomy, and precaution. Therefore, the participant assumes an active role in the success or suspension of the investigation, and the investigators are responsible for respecting the informed and free decision.O consentimento informado é um dos pilares da investigação e considerado imperativo numa perspetiva ética. Atendendo aos respetivos princípios e ao processo de investigação cada vez mais rigoroso, responsável e complexo, torna-se desafiante a reflexão sobre a sua validade na perspetiva ética e deontológica. Assistimos ao rápido desenvolvimento do conhecimento na biomedicina e, associado a uma inovação tecnológica sem prece- dentes, verifica-se uma maior complexidade dos estudos e, consequentemente, do consentimento informado. Considera-se, portanto, a simplificação e validação das informações a serem transmitidas ao participante, a possibilidade de prorrogação do prazo para esclarecimento de possíveis dúvidas, a utilização de ferramentas de apoio e a otimização da comunicação por parte dos pesquisadores. Outros aspetos a ter em linha de conta pelos investigadores são os termos excessivamente técnicos, as informações de difícil interpretação, esclarecimento resumido, culturas diferentes e as ideologias sociopolíticas. Dadas as várias dimensões jurídicas do consentimento, demonstra-se a relevância do exercício livre e informado dos direitos previstos na lei, no desenvolvimento científico em saúde. Além de ser uma oportunidade de comunicação efetiva, o consentimento informado deve ser baseado numa relação de confiança entre o investigador e o participante, baseada em princípios éticos. Estes são essenciais para o desenvolvimento de investigações racionais e robustas, orientando de alguma forma o trabalho a ser desenvolvido pelos investigadores, baseando-se nos princípios da beneficência, não maleficência, justiça, autonomia e precaução. Assim, o participante assume um papel ativo no sucesso ou inviabilidade da investigação, cabendo aos investigadores respeitar uma decisão livre e esclarecida

Post-mortem digital forensics analysis of the Zepp Life android application

CIIC partially supported this research under the project UIDB 04524/2020 by FCT/MCTES and EU funds under the project UIDB/EEA 50008/2020.This paper studies the post-mortem digital forensic artifacts left by the Android Zepp Life (formerly Mi Fit) mobile application when used in conjunction with a Xiaomi Mi Band 6. The Mi Band 6 is a low-cost smart band device with several sensors that allow for health and activity monitoring, collecting metrics such as heart rate, blood oxygen saturation level, and step count. The device communicates via Bluetooth Low Energy with the Zepp Life application, which displays its data, provides some controls, and acts as a bridge to the Internet. We study, from a digital forensics perspective, the Android version of the mobile application in a rooted smartphone. For this purpose, we analyze the data repositories, namely its databases and XML files, and correlate the data on the smartphone with the corresponding usage of the Mi Band device. The paper also presents two open-source scripts we have developed to ease the task of forensic practitioners dealing with Zepp Life/Mi Band 6: ZL_std and ZL_autopsy. The former refers to a Python 3 script that extracts high-level views of Zepp Life data through the command-line, whereas the latter is a module that integrates ZL_std functionalities within the popular open-source Autopsy digital forensic software. Data stored on the Android companion device of a Mi Band 6 might include GPS coordinates, events and alarms, and biometric data such as heart rate, sleep time, and fitness activity, which can be valuable digital forensic artifacts.info:eu-repo/semantics/publishedVersio

Comunicação, concorrência e processos

Texto de apoio escrito no âmbito da disciplina de Opção I - Processos, Objectos e Comunicação (1994/95), leccionada à Lic. em Matemática e Ciências de Computação

Genetic Evidence for p75NTR-Dependent Tetraploidy in Cortical Projection Neurons from Adult Mice

A subpopulation of chick retinal projection neurons becomes tetraploid during development, an event prevented by blocking antibodies against p75 neurotrophin receptor (p75(NTR)). We have used an optimized flow cytometric assay, based on the analysis of unfixed brain cell nuclei, to study whether p75(NTR)-dependent neuronal tetraploidization takes place in the cerebral cortex, giving rise to projection neurons as well. We show that 3% of neurons in both murine neocortex and chick telencephalic derivatives are tetraploid, and that in the mouse ~85% of these neurons express the immediate early genes Erg-1 and c-Fos, indicating that they are functionally active. Tetraploid cortical neurons (65-80%) express CTIP2, a transcription factor specific for subcortical projection neurons in the mouse neocortex. During the period in which these neurons are born, p75(NTR) is detected in differentiating neurons undergoing DNA replication. Accordingly, p75(NTR)-deficient mice contain a reduced proportion of both NeuN and CTIP2-positive neocortical tetraploid neurons, thus providing genetic evidence for the participation of p75(NTR) in the induction of neuronal tetraploidy in the mouse neocortex. In the striatum tetraploidy is mainly associated with long-range projection neurons as well since ~80% of tetraploid neurons in this structure express calbindin, a marker of neostriatal-matrix spiny neurons, known to establish long-range projections to the substantia nigra and globus pallidus. In contrast, only 20% of tetraploid cortical neurons express calbindin, which is mainly expressed in layers II-III, where CTIP2 is absent. We conclude that tetraploidy mainly affects long-range projection neurons, being facilitated by p75(NTR) in the neocortex.Peer Reviewe

Navegar é preciso...

Introdução simples à situação actual das redes de computadores em Portugal, assim como à rede Internet e aos protocolos de comunicação mais utilizados nessa rede (telnet, ftp, finger, mail, gofer, http, ...). Os destinatários são todas as pessoas que pretendam iniciar-se ou aprender mais qualquer coisa sobre os "segredos" da comunicação e navegação numa rede de computadores

El retablo de la capilla de Nuestra Señora de la Piedad en el claustro de la Catedral de Oporto: estudio, conservación y restauración

The retable located in the Chapel of Our Lady of Mercy, in the cloisters of Oporto’s cathedral, dates back to the 17th century. Artistically, it belongs to a transition period between the Mannerism and the Baroque styles. The artistic value and the lack of documented information about the artwork led to the development of a project contemplating its the study. Both chemical and physical analyses - observation of the support, micro-FTIR and SEM-EDS - suggest that the retable was carved in sweet chestnut wood, accordingly to the techniques used at the time. The retable presents water-gilded areas contrasting with blue and red phytomorphic motifs. The polychromed areas were later covered with lead white paint. There were also evidences of previous conservation-restoration interventions. The frail condition of the retable’s materials testified the need to conserve and restore it. Among other procedures, the materials were consolidated and the lacunae were filled and inpainted - partially regenerating the artwork’s aesthetic unity.O retábulo de Nossa Senhora da Piedade encontra-se na capela homónima no claustro da Sé do Porto. Executada no século XVII, trata-se de um obra de transição estilística entre o Maneirismo e o Barroco. O valor patrimonial da obra e a ausência de estudos mais profundos sobre a mesma, motivaram a necessidade de a caracterizar. As análises realizadas (observação do suporte, micro-FTIR e SEM-EDS) permitiram concluir que se trata de uma obra artística em madeira de castanho, executada segundo as técnicas comuns à época. O retábulo apresenta zonas de douramento a água, que contrastam com os vestígios de decorações fitomórficas em tons de azul e vermelho, os quais foram posteriormente repolicromados a branco de chumbo. Existem também evidências de intervenções de conservação e restauro anteriores. Entre outros tratamentos realizou-se: a consolidação dos materiais presentes, a aplicação de massas de preenchimento nas lacunas e a reintegração cromática das mesmas – devolvendo parcialmente à obra a sua integridade estética.El retablo de Nuestra Señora de la Piedad se encuentra en la capilla homónima del claustro de la Catedral de Oporto. Creada en el siglo XVII, es una obra de transición estilística entre el Manierismo y el Barroco. El valor patrimonial de la obra y la ausencia de estudios más profundos sobre ella, motivaron su caracterización. Los análisis realizados sobre el retablo (observación del suporte, micro-FTIR y SEM-EDS) permitirán concluir que se trata de una obra de madera de castaño, ejecutado conforme a las técnicas comunes de la época. La pieza presenta zonas de dorado al agua, que contrastan con vestigios de decoraciones fitomorfas en tonos azul y rojo, las cuales fueron posteriormente repolicromadas con blanco de plomo. Existían también evidencias de intervenciones de conservación y restauración anteriores. Conjuntamente, las patologías identificadas demostraron la urgencia de realizar una intervención de conservación – restauración. Entre otros tratamientos se realizó: la consolidación de los materiales presentes, se aplicó pasta de relleno en las lagunas, y se reintegró con color las mismas - devolviendo parte de la integridad estética de la obra.info:eu-repo/semantics/publishedVersio

Permutability in proof terms for intuitionistic sequent calculus with cuts

This paper gives a comprehensive and coherent view on permutability in the intuitionistic sequent calculus with cuts. Specifically we show that, once permutability is packaged into appropriate global reduction procedures, it organizes the internal structure of the system and determines fragments with computational interest, both for the computation-as-proof-normalization and the computation-as-proof-search paradigms. The vehicle of the study is a lambda-calculus of multiary proof terms with generalized application, previously developed by the authors (the paper argues this system represents the simplest fragment of ordinary sequent calculus that does not fall into mere natural deduction). We start by adapting to our setting the concept of normal proof, developed by Mints, Dyckhoff, and Pinto, and by defining natural proofs, so that a proof is normal iff it is natural and cut-free. Natural proofs form a subsystem with a transparent Curry-Howard interpretation (a kind of formal vector notation for lambda-terms with vectors consisting of lists of lists of arguments), while searching for normal proofs corresponds to a slight relaxation of focusing (in the sense of LJT). Next, we define a process of permutative conversion to natural form, and show that its combination with cut elimination gives a concept of normalization for the sequent calculus. We derive a systematic picture of the full system comprehending a rich set of reduction procedures (cut elimination, flattening, permutative conversion, normalization, focalization), organizing the relevant subsystems and the important subclasses of cut-free, normal, and focused proofs.Partially financed by FCT through project UID/MAT/00013/2013, and by COST action CA15123 EUTYPES. The first and the last authors were partially financed by Fundação para a Ciência e a Tecnologia (FCT) through project UID/MAT/00013/2013. The first author got financial support by the COST action CA15123 EUTYPES.info:eu-repo/semantics/publishedVersio

From bench to bedside: Calprotectin (S100A8/S100A9) as a biomarker in rheumatoid arthritis

S100A9/S100A8 (calprotectin), a member of the S100 protein family, has been shown to play a pivotal role in innate immunity activation. Calprotectin plays a critical role in the pathogenesis of rheumatoid arthritis (RA), as it triggers chemotaxis, phagocyte migration and modulation of neutrophils and macrophages. Higher calprotectin levels have been found in synovial fluid, plasma, and serum from RA patients. Recent studies have demonstrated better correlations between serum or plasma calprotectin and composite inflammatory disease activity indexes than c-reactive protein (CRP) or the erythrocyte sedimentation rate (ESR). Calprotectin serum levels decreased after treatment, independently of the DMARD type or strategy. Calprotectin has shown the strongest correlations with other sensitive techniques to detect inflammation, such as ultrasound. Calprotectin independently predicts radiographic progression. However, its value as a biomarker of treatment response and flare after tapering is unclear. This update reviews the current understanding of calprotectin in RA and discusses possible applications as a biomarker in clinical practice

Post-mortem digital forensic artifacts of TikTok Android App

TikTok is a social network known mostly for the creation and shar ing of short videos and for its popularity for those under 30 years old. Although it has only appeared as Android and iOS apps in 2017, it has gathered a large user base, being one of the most downloaded and used app. In this paper, we study the digital forensic artifacts of TikTok’s app that can be recovered with a post mortem analysis of an Android phone, detailing the databases and XML with data that might be relevant for a digital forensic practitioner. We also provide the module tiktok.py to extract several forensic artifacts of TikTok in a digital forensic analysis of an Android phone. The module runs under Autopsy’s Android Analyzer environment. Although TikTok offers a rich set of features, it is very internet-dependent, with a large amount of its inner data kept on the cloud, and thus not easily accessible in a post mortem analysis. Nonetheless, we were able to recover messages exchanged through the app commu nications channels, the list of TikTok users that have interacted with the TikTok account used at the smartphone, photos linked to the app and in some circumstances, TikTok’s videos watched by the smartphone’s user.info:eu-repo/semantics/publishedVersio